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Sample records for adaptation strategies based

  1. A biological modeling based comparison of two strategies for adaptive radiotherapy of urinary bladder cancer.

    PubMed

    Lutkenhaus, L J; Vestergaard, A; Bel, A; Høyer, M; Hulshof, M C C M; van Leeuwen, C M; Casares-Magaz, O; Petersen, J B; Søndergaard, J; Muren, L P

    2016-08-01

    Background Adaptive radiotherapy is introduced in the management of urinary bladder cancer to account for day-to-day anatomical changes. The purpose of this study was to determine whether an adaptive plan selection strategy using either the first four cone beam computed tomography scans (CBCT-based strategy) for plan creation, or the interpolation of bladder volumes on pretreatment CT scans (CT-based strategy), is better in terms of tumor control probability (TCP) and normal tissue sparing while taking the clinically applied fractionation schedules also into account. Material and methods With the CT-based strategy, a library of five plans was created. Patients received 55 Gy to the bladder tumor and 40 Gy to the non-involved bladder and lymph nodes, in 20 fractions. With the CBCT-based strategy, a library of three plans was created, and patients received 70 Gy to the tumor, 60 Gy to the bladder and 48 Gy to the lymph nodes, in 30-35 fractions. Ten patients were analyzed for each adaptive plan selection strategy. TCP was calculated applying the clinically used fractionation schedules, as well as a rescaling of the dose from 55 to 70 Gy for the CT-based strategy. For rectum and bowel, equivalent doses in 2 Gy fractions (EQD2) were calculated. Results The CBCT-based strategy resulted in a median TCP of 75%, compared to 49% for the CT-based strategy, the latter improving to 72% upon rescaling the dose to 70 Gy. A median rectum V30Gy (EQD2) of 26% [interquartile range (IQR): 8-52%] was found for the CT-based strategy, compared to 58% (IQR: 55-73%) for the CBCT-based strategy. Also the bowel doses were lower with the CT-based strategy. Conclusions Whereas the higher total bladder TCP for the CBCT-based strategy is due to prescription differences, the adaptive strategy based on CT scans results in the lowest rectum and bowel cavity doses.

  2. Strategies for adding adaptive learning mechanisms to rule-based diagnostic expert systems

    NASA Technical Reports Server (NTRS)

    Stclair, D. C.; Sabharwal, C. L.; Bond, W. E.; Hacke, Keith

    1988-01-01

    Rule-based diagnostic expert systems can be used to perform many of the diagnostic chores necessary in today's complex space systems. These expert systems typically take a set of symptoms as input and produce diagnostic advice as output. The primary objective of such expert systems is to provide accurate and comprehensive advice which can be used to help return the space system in question to nominal operation. The development and maintenance of diagnostic expert systems is time and labor intensive since the services of both knowledge engineer(s) and domain expert(s) are required. The use of adaptive learning mechanisms to increment evaluate and refine rules promises to reduce both time and labor costs associated with such systems. This paper describes the basic adaptive learning mechanisms of strengthening, weakening, generalization, discrimination, and discovery. Next basic strategies are discussed for adding these learning mechanisms to rule-based diagnostic expert systems. These strategies support the incremental evaluation and refinement of rules in the knowledge base by comparing the set of advice given by the expert system (A) with the correct diagnosis (C). Techniques are described for selecting those rules in the in the knowledge base which should participate in adaptive learning. The strategies presented may be used with a wide variety of learning algorithms. Further, these strategies are applicable to a large number of rule-based diagnostic expert systems. They may be used to provide either immediate or deferred updating of the knowledge base.

  3. Adaptation strategies for high order discontinuous Galerkin methods based on Tau-estimation

    NASA Astrophysics Data System (ADS)

    Kompenhans, Moritz; Rubio, Gonzalo; Ferrer, Esteban; Valero, Eusebio

    2016-02-01

    In this paper three p-adaptation strategies based on the minimization of the truncation error are presented for high order discontinuous Galerkin methods. The truncation error is approximated by means of a τ-estimation procedure and enables the identification of mesh regions that require adaptation. Three adaptation strategies are developed and termed a posteriori, quasi-a priori and quasi-a priori corrected. All strategies require fine solutions, which are obtained by enriching the polynomial order, but while the former needs time converged solutions, the last two rely on non-converged solutions, which lead to faster computations. In addition, the high order method permits the spatial decoupling for the estimated errors and enables anisotropic p-adaptation. These strategies are verified and compared in terms of accuracy and computational cost for the Euler and the compressible Navier-Stokes equations. It is shown that the two quasi-a priori methods achieve a significant reduction in computational cost when compared to a uniform polynomial enrichment. Namely, for a viscous boundary layer flow, we obtain a speedup of 6.6 and 7.6 for the quasi-a priori and quasi-a priori corrected approaches, respectively.

  4. Adaptive isogeometric analysis based on a combined r-h strategy

    NASA Astrophysics Data System (ADS)

    Basappa, Umesh; Rajagopal, Amirtham; Reddy, J. N.

    2016-03-01

    In the present work, an r-h adaptive isogeometric analysis is proposed for plane elasticity problems. For performing the r-adaption, the control net is considered to be a network of springs with the individual spring stiffness values being proportional to the error estimated at the control points. While preserving the boundary control points, relocation of only the interior control points is made by adopting a successive relaxation approach to achieve the equilibrium of spring system. To suit the noninterpolatory nature of the isogeometric approximation, a new point-wise error estimate for the h-refinement is proposed. To evaluate the point-wise error, hierarchical B-spline functions in Sobolev spaces are considered. The proposed adaptive h-refinement strategy is based on using De-Casteljau's algorithm for obtaining the new control points. The subsequent control meshes are thus obtained by using a recursive subdivision of reference control mesh. Such a strategy ensures that the control points lie in the physical domain in subsequent refinements, thus making the physical mesh to exactly interpolate the control mesh and thereby allowing the exact imposition of essential boundary conditions in the classical isogeometric analysis (IGA). The combined r-h adaptive refinement strategy results in better convergence characteristics with reduced errors than r- or h-refinement. Several numerical examples are presented to illustrate the efficiency of the proposed approach.

  5. Compromise-based Robust Prioritization of Climate Change Adaptation Strategies for Watershed Management

    NASA Astrophysics Data System (ADS)

    Kim, Y.; Chung, E. S.

    2014-12-01

    This study suggests a robust prioritization framework for climate change adaptation strategies under multiple climate change scenarios with a case study of selecting sites for reusing treated wastewater (TWW) in a Korean urban watershed. The framework utilizes various multi-criteria decision making techniques, including the VIKOR method and the Shannon entropy-based weights. In this case study, the sustainability of TWW use is quantified with indicator-based approaches with the DPSIR framework, which considers both hydro-environmental and socio-economic aspects of the watershed management. Under the various climate change scenarios, the hydro-environmental responses to reusing TWW in potential alternative sub-watersheds are determined using the Hydrologic Simulation Program in Fortran (HSPF). The socio-economic indicators are obtained from the statistical databases. Sustainability scores for multiple scenarios are estimated individually and then integrated with the proposed approach. At last, the suggested framework allows us to prioritize adaptation strategies in a robust manner with varying levels of compromise between utility-based and regret-based strategies.

  6. A novel model-based adaptive control strategy for step-feed SBRs dealing with influent fluctuation.

    PubMed

    Luo, Tao; Yang, Min; Han, Jingyi; Sun, Peide

    2014-09-01

    A novel model-based adaptive control strategy for step-feed sequence batch reactors (SBRs) was developed and compared with traditional fixed-parameters control strategy and statically optimal parameters control strategy under influent fluctuation period. The SBR was operated with automatic alteration of the operating parameters based on the numerical calculation results of fully coupled activated sludge model (FCASM). Since the influent fluctuated from one cycle to another, model-based adaptive control strategy was applied to optimize the operating parameters of the SBR accordingly. By using the model-based adaptive control strategy, the average removal efficiencies for total nitrogen (TN) and total phosphorus (TP) achieved in fluctuation tests were over 84% and 98%, respectively. Compared to traditional fixed-parameters strategy, the TN removal efficiency was improved by 25.11%.

  7. Covariance Matrix Adapted Evolution Strategy Based Design of Mixed H2/H ∞ PID Controller

    NASA Astrophysics Data System (ADS)

    Willjuice Iruthayarajan, M.; Baskar, S.

    This paper discusses the application of the covariance matrix adapted evolution strategy (CMAES) technique to the design of the mixed H2/H ∞ PID controller. The optimal robust PID controller is designed by minimizing the weighted sum of integral squared error (ISE) and balanced robust performance criterion involving robust stability and disturbance attenuation performance subjected to robust stability and disturbance attenuation constraints. In CMAES algorithm, these constraints are effectively handled by penalty parameter-less scheme. In order to test the performance of CMAES algorithm, MIMO distillation column model is considered. For the purpose of comparison, reported intelligent genetic algorithm (IGA) method is used. The statistical performances of combined ISE and balanced robust performance criterion in ten independent simulation runs show that a performance of CMAES is better than IGA method. Robustness test conducted on the system also shows that the robust performance of CMAES designed controller is better than IGA based controller under model uncertainty and external disturbances.

  8. Expressing Adaptation Strategies Using Adaptation Patterns

    ERIC Educational Resources Information Center

    Zemirline, N.; Bourda, Y.; Reynaud, C.

    2012-01-01

    Today, there is a real challenge to enable personalized access to information. Several systems have been proposed to address this challenge including Adaptive Hypermedia Systems (AHSs). However, the specification of adaptation strategies remains a difficult task for creators of such systems. In this paper, we consider the problem of the definition…

  9. Enhancing adaptive sparse grid approximations and improving refinement strategies using adjoint-based a posteriori error estimates

    SciTech Connect

    Jakeman, J.D. Wildey, T.

    2015-01-01

    In this paper we present an algorithm for adaptive sparse grid approximations of quantities of interest computed from discretized partial differential equations. We use adjoint-based a posteriori error estimates of the physical discretization error and the interpolation error in the sparse grid to enhance the sparse grid approximation and to drive adaptivity of the sparse grid. Utilizing these error estimates provides significantly more accurate functional values for random samples of the sparse grid approximation. We also demonstrate that alternative refinement strategies based upon a posteriori error estimates can lead to further increases in accuracy in the approximation over traditional hierarchical surplus based strategies. Throughout this paper we also provide and test a framework for balancing the physical discretization error with the stochastic interpolation error of the enhanced sparse grid approximation.

  10. Enhancing adaptive sparse grid approximations and improving refinement strategies using adjoint-based a posteriori error estimates

    DOE PAGES

    Jakeman, J. D.; Wildey, T.

    2015-01-01

    In this paper we present an algorithm for adaptive sparse grid approximations of quantities of interest computed from discretized partial differential equations. We use adjoint-based a posteriori error estimates of the interpolation error in the sparse grid to enhance the sparse grid approximation and to drive adaptivity. We show that utilizing these error estimates provides significantly more accurate functional values for random samples of the sparse grid approximation. We also demonstrate that alternative refinement strategies based upon a posteriori error estimates can lead to further increases in accuracy in the approximation over traditional hierarchical surplus based strategies. Throughout this papermore » we also provide and test a framework for balancing the physical discretization error with the stochastic interpolation error of the enhanced sparse grid approximation.« less

  11. Enhancing adaptive sparse grid approximations and improving refinement strategies using adjoint-based a posteriori error estimates

    SciTech Connect

    Jakeman, J. D.; Wildey, T.

    2015-01-01

    In this paper we present an algorithm for adaptive sparse grid approximations of quantities of interest computed from discretized partial differential equations. We use adjoint-based a posteriori error estimates of the interpolation error in the sparse grid to enhance the sparse grid approximation and to drive adaptivity. We show that utilizing these error estimates provides significantly more accurate functional values for random samples of the sparse grid approximation. We also demonstrate that alternative refinement strategies based upon a posteriori error estimates can lead to further increases in accuracy in the approximation over traditional hierarchical surplus based strategies. Throughout this paper we also provide and test a framework for balancing the physical discretization error with the stochastic interpolation error of the enhanced sparse grid approximation.

  12. A Support Method with Changeable Training Strategies Based on Mutual Adaptation between a Ubiquitous Pet and a Learner

    NASA Astrophysics Data System (ADS)

    Ye, Xianzhi; Jing, Lei; Kansen, Mizuo; Wang, Junbo; Ota, Kaoru; Cheng, Zixue

    With the progress of ubiquitous technology, ubiquitous learning presents new opportunities to learners. Situations of a learner can be grasped through analyzing the learner's actions collected by sensors, RF-IDs, or cameras in order to provide support at proper time, proper place, and proper situation. Training for acquiring skills and enhancing physical abilities through exercise and experience in the real world is an important domain in u-learning. A training program may last for several days and has one or more training units (exercises) for a day. A learner's performance in a unit is considered as short term state. The performance in a series of units may change with patterns: progress, plateau, and decline. Long term state in a series of units is accumulatively computed based on short term states. In a learning/training program, it is necessary to apply different support strategies to adapt to different states of the learner. Adaptation in learning support is significant, because a learner loses his/her interests easily without adaptation. Systems with the adaptive support usually provide stimulators to a learner, and a learner can have a great motivation in learning at beginning. However, when the stimulators reach some levels, the learner may lose his/her motivation, because the long term state of the learner changes dynamically, which means a progress state may change to a plateau state or a decline state. In different long term learning states, different types of stimulators are needed. However, the stimulators and advice provided by the existing systems are monotonic without changeable support strategies. We propose a mutual adaptive support. The mutual adaptation means each of the system and the learner has their own states. On one hand, the system tries to change its state to adapt to the learner's state for providing adaptive support. On the other hand, the learner can change its performance following the advice given based on the state of the system

  13. A novel kernel extreme learning machine algorithm based on self-adaptive artificial bee colony optimisation strategy

    NASA Astrophysics Data System (ADS)

    Ma, Chao; Ouyang, Jihong; Chen, Hui-Ling; Ji, Jin-Chao

    2016-04-01

    In this paper, we propose a novel learning algorithm, named SABC-MKELM, based on a kernel extreme learning machine (KELM) method for single-hidden-layer feedforward networks. In SABC-MKELM, the combination of Gaussian kernels is used as the activate function of KELM instead of simple fixed kernel learning, where the related parameters of kernels and the weights of kernels can be optimised by a novel self-adaptive artificial bee colony (SABC) approach simultaneously. SABC-MKELM outperforms six other state-of-the-art approaches in general, as it could effectively determine solution updating strategies and suitable parameters to produce a flexible kernel function involved in SABC. Simulations have demonstrated that the proposed algorithm not only self-adaptively determines suitable parameters and solution updating strategies learning from the previous experiences, but also achieves better generalisation performances than several related methods, and the results show good stability of the proposed algorithm.

  14. Strategies to overcome photobleaching in algorithm-based adaptive optics for nonlinear in-vivo imaging.

    PubMed

    Caroline Müllenbroich, M; McGhee, Ewan J; Wright, Amanda J; Anderson, Kurt I; Mathieson, Keith

    2014-01-01

    We have developed a nonlinear adaptive optics microscope utilizing a deformable membrane mirror (DMM) and demonstrated its use in compensating for system- and sample-induced aberrations. The optimum shape of the DMM was determined with a random search algorithm optimizing on either two photon fluorescence or second harmonic signals as merit factors. We present here several strategies to overcome photobleaching issues associated with lengthy optimization routines by adapting the search algorithm and the experimental methodology. Optimizations were performed on extrinsic fluorescent dyes, fluorescent beads loaded into organotypic tissue cultures and the intrinsic second harmonic signal of these cultures. We validate the approach of using these preoptimized mirror shapes to compile a robust look-up table that can be applied for imaging over several days and through a variety of tissues. In this way, the photon exposure to the fluorescent cells under investigation is limited to imaging. Using our look-up table approach, we show signal intensity improvement factors ranging from 1.7 to 4.1 in organotypic tissue cultures and freshly excised mouse tissue. Imaging zebrafish in vivo, we demonstrate signal improvement by a factor of 2. This methodology is easily reproducible and could be applied to many photon starved experiments, for example fluorescent life time imaging, or when photobleaching is a concern.

  15. COREDAR: COmmunicating Risk of sea level rise and Engaging stakeholDers in framing community based Adaptation stRategies

    NASA Astrophysics Data System (ADS)

    Amsad Ibrahim Khan, S. K.; Chen, R. S.; de Sherbinin, A. M.; Andimuthu, R.; Kandasamy, P.

    2015-12-01

    Accelerated sea-level rise (SLR) is a major long term outcome of climate change leading to increased inundation of low-lying areas. Particularly, global cities that are located on or near the coasts are often situated in low lying areas and these locations put global cities at greater risk to SLR. Localized flooding will profoundly impact vulnerable communities located in high-risk urban areas. Building community resilience and adapting to SLR is increasingly a high priority for cities. On the other hand, Article 6 of the United Nations Framework Convention on Climate Change addresses the importance of climate change communication and engaging stakeholders in decision making process. Importantly, Community Based Adaptation (CBA) experiences emphasize that it is important to understand a community's unique perceptions of their adaptive capacities to identify useful solutions and that scientific and technical information on anticipated coastal climate impacts needs to be translated into a suitable language and format that allows people to be able to participate in adaptation planning. To address this challenge, this study has put forth three research questions from the lens of urban community engagement in SLR adaptation, (1) What, if any, community engagement in addressing SLR occurring in urban areas; (2) What information do communities need and how does it need to be communicated, in order to be better prepared and have a greater sense of agency? and (3) How can government agencies from city to federal levels facilitate community engagement and action?. To answer these questions this study has evolved a framework "COREDAR" (COmmunicating Risk of sea level rise and Engaging stakeholDers in framing community based Adaptation StRategies) to communicate and transfer complex climate data and information such as projected SLR under different scenarios of IPCC AR5, predicted impact of SLR, prioritizing vulnerability, etc. to concerned stakeholders and local communities

  16. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks.

    PubMed

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M

    2015-09-18

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries.

  17. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks

    PubMed Central

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M.

    2015-01-01

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries. PMID:26393612

  18. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks.

    PubMed

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M

    2015-01-01

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries. PMID:26393612

  19. Micro practices of coordination based on complex adaptive systems: user needs and strategies for coordinating public health in Denmark

    PubMed Central

    Wittrup, Inge; Burau, Viola

    2015-01-01

    Introduction Many highly formalised approaches to coordination poorly fit public health and recent studies call for coordination based on complex adaptive systems. Our contribution is two-fold. Empirically, we focus on public health, and theoretically we build on the patient perspective and treat coordination as a process of contingent, two-level negotiations of user needs. Theory and Methods The paper draws on the concept of user needs-based coordination and sees coordination as a process, whereby needs emerging from the life world of the user are made amenable to the health system through negotiations. The analysis is based on an explorative case study of a health promotion initiative in Denmark. It adopts an anthropological qualitative approach and uses a range of qualitative data. Results The analysis identifies four strategies of coordination: the coordinator focusing on the individual user or on relations with other professionals; and the manager coaching the coordinator or providing structural support. Crucially, the coordination strategies by management remain weak as they do not directly relate to specific user needs. Discussion In process of bottom-up negotiations user needs become blurred and this is especially a challenge for management. The study therefore calls for an increased focus on the level nature of negotiations to bridge the gap that currently weakens coordination strategies by management. PMID:26528097

  20. Research-Based Language Intervention Strategies Adapted for Deaf and Hard of Hearing Children.

    ERIC Educational Resources Information Center

    Luetke-Stahlman, Barbara

    1993-01-01

    Strategies to facilitate the language development of children with deafness or hearing impairments are presented, including capitalizing on the linguistic opportunities provided in particular environments; rearranging environments; responding to indications that children have comprehended messages and are open to risk communication; and…

  1. Adaptive Control Strategies for Flexible Robotic Arm

    NASA Technical Reports Server (NTRS)

    Bialasiewicz, Jan T.

    1996-01-01

    The control problem of a flexible robotic arm has been investigated. The control strategies that have been developed have a wide application in approaching the general control problem of flexible space structures. The following control strategies have been developed and evaluated: neural self-tuning control algorithm, neural-network-based fuzzy logic control algorithm, and adaptive pole assignment algorithm. All of the above algorithms have been tested through computer simulation. In addition, the hardware implementation of a computer control system that controls the tip position of a flexible arm clamped on a rigid hub mounted directly on the vertical shaft of a dc motor, has been developed. An adaptive pole assignment algorithm has been applied to suppress vibrations of the described physical model of flexible robotic arm and has been successfully tested using this testbed.

  2. Individualized Nonadaptive and Online-Adaptive Intensity-Modulated Radiotherapy Treatment Strategies for Cervical Cancer Patients Based on Pretreatment Acquired Variable Bladder Filling Computed Tomography Scans

    SciTech Connect

    Bondar, M.L.; Hoogeman, M.S.; Mens, J.W.; Quint, S.; Ahmad, R.; Dhawtal, G.; Heijmen, B.J.

    2012-08-01

    Purpose: To design and evaluate individualized nonadaptive and online-adaptive strategies based on a pretreatment established motion model for the highly deformable target volume in cervical cancer patients. Methods and Materials: For 14 patients, nine to ten variable bladder filling computed tomography (CT) scans were acquired at pretreatment and after 40 Gy. Individualized model-based internal target volumes (mbITVs) accounting for the cervix and uterus motion due to bladder volume changes were generated by using a motion-model constructed from two pretreatment CT scans (full and empty bladder). Two individualized strategies were designed: a nonadaptive strategy, using an mbITV accounting for the full-range of bladder volume changes throughout the treatment; and an online-adaptive strategy, using mbITVs of bladder volume subranges to construct a library of plans. The latter adapts the treatment online by selecting the plan-of-the-day from the library based on the measured bladder volume. The individualized strategies were evaluated by the seven to eight CT scans not used for mbITVs construction, and compared with a population-based approach. Geometric uniform margins around planning cervix-uterus and mbITVs were determined to ensure adequate coverage. For each strategy, the percentage of the cervix-uterus, bladder, and rectum volumes inside the planning target volume (PTV), and the clinical target volume (CTV)-to-PTV volume (volume difference between PTV and CTV) were calculated. Results: The margin for the population-based approach was 38 mm and for the individualized strategies was 7 to 10 mm. Compared with the population-based approach, the individualized nonadaptive strategy decreased the CTV-to-PTV volume by 48% {+-} 6% and the percentage of bladder and rectum inside the PTV by 5% to 45% and 26% to 74% (p < 0.001), respectively. Replacing the individualized nonadaptive strategy by an online-adaptive, two-plan library further decreased the percentage of

  3. Regional Adaptation Strategies in Central Germany

    NASA Astrophysics Data System (ADS)

    Marx, Andreas

    2013-04-01

    Climate change presents a major challenge on international, national, and regional scale. It affects the scientific world as well as policymakers, representatives of economy, and the public. Consequently, the need for a dialogue between experts in climate change and the people affected is needed. However, structuring and communicating climate change information on the various scales is challenging and demands coordination. Within the Helmholtz community in Germany, four regional Helmholtz climate offices are founded. One of their major goals is to encourage the communication between science and public. Primarily, this is done by close cooperation to the Helmholtz research centers at which each climate office is hosted. Second, a continuous exchange is supported beyond the Helmholtz research centers towards universities and authorities at state and federal level. Each regional Helmholtz climate office represents regional aspects of climate related research based on the scientific expertise from the hosting Helmholtz research institutes. In the Climate Office for central Germany, Land use changes are among the most important factors of climate change driven environmental changes which have to be managed by the society in the next years. Since 1991 UFZ scientists research the causes and consequences of far-reaching environmental changes. The Climate Office offers information about climate change effects on the environmental compartments, land use strategies as well as regional strategies of adaptation. The three federal states in Central Germany (Saxony, Saxony-Anhalt and Thuringia) handle adaptation to climate change very differently. The presentation focusses on alikeness and differences in the adaptation process.

  4. When to throw the switch: The adaptiveness of modifying emotion regulation strategies based on affective and physiological feedback.

    PubMed

    Birk, Jeffrey L; Bonanno, George A

    2016-08-01

    Particular emotion regulation (ER) strategies are beneficial in certain contexts, but little is known about the adaptiveness of switching strategies after implementing an initial strategy. Research and theory on regulatory flexibility suggest that people switch strategies dynamically and that internal states provide feedback indicating when switches are appropriate. Frequent switching may predict positive outcomes among people who respond to this feedback. We investigated whether internal feedback (particularly corrugator activity, heart rate, or subjective negative intensity) guides people to switch to an optimal (i.e., distraction) but not nonoptimal (i.e., reappraisal) strategy for regulating strong emotion. We also tested whether switching frequency and responsiveness to internal feedback (RIF) together predict well-being. While attempting to regulate emotion elicited by unpleasant pictures, participants could switch to an optimal (Study 1; reappraisal-to-distraction order; N = 90) or nonoptimal (Study 2; distraction-to-reappraisal order; N = 95) strategy for high-arousal emotion. A RIF score for each emotion measure indexed the relative strength of emotion during the initial phase for trials on which participants later switched strategies. As hypothesized, negative intensity, corrugator activity, and the magnitude of heart rate deceleration during this early phase were higher on switch than maintain trials in Study 1 only. Critically, in Study 1 only, greater switching frequency predicted higher and lower life satisfaction for participants with high and low corrugator RIF, respectively, even after controlling for reappraisal success. Individual differences in RIF may contribute to subjective well-being provided that the direction of strategy switching aligns well with regulatory preferences for high emotion. (PsycINFO Database Record PMID:26900993

  5. Adaptive strategy for joint measurements

    NASA Astrophysics Data System (ADS)

    Uola, Roope; Luoma, Kimmo; Moroder, Tobias; Heinosaari, Teiko

    2016-08-01

    We develop a technique to find simultaneous measurements for noisy quantum observables in finite-dimensional Hilbert spaces. We use the method to derive lower bounds for the noise needed to make incompatible measurements jointly measurable. Using our strategy together with recent developments in the field of one-sided quantum information processing we show that the attained lower bounds are tight for various symmetric sets of quantum measurements. We use this characterisation to prove the existence of so called 4-Specker sets, i.e. sets of four incompatible observables with compatible subsets in the qubit case.

  6. Multigrid solution strategies for adaptive meshing problems

    NASA Technical Reports Server (NTRS)

    Mavriplis, Dimitri J.

    1995-01-01

    This paper discusses the issues which arise when combining multigrid strategies with adaptive meshing techniques for solving steady-state problems on unstructured meshes. A basic strategy is described, and demonstrated by solving several inviscid and viscous flow cases. Potential inefficiencies in this basic strategy are exposed, and various alternate approaches are discussed, some of which are demonstrated with an example. Although each particular approach exhibits certain advantages, all methods have particular drawbacks, and the formulation of a completely optimal strategy is considered to be an open problem.

  7. Climate change adaptation strategies and mitigation policies

    NASA Astrophysics Data System (ADS)

    García Fernández, Cristina

    2015-04-01

    The pace of climate change and the consequent warming of the Earth's surface is increasing vulnerability and decreasing adaptive capacity. Achieving a successful adaptation depends on the development of technology, institutional organization, financing availability and the exchange of information. Populations living in arid and semi-arid zones, low-lying coastal areas, land with water shortages or at risk of overflow or small islands are particularly vulnerable to climate change. Due to increasing population density in sensitive areas, some regions have become more vulnerable to events such as storms, floods and droughts, like the river basins and coastal plains. Human activities have fragmented and increased the vulnerability of ecosystems, which limit both, their natural adaptation and the effectiveness of the measures adopted. Adaptation means to carry out the necessary modifications for society to adapt to new climatic conditions in order to reduce their vulnerability to climate change. Adaptive capacity is the ability of a system to adjust to climate change (including climate variability and extremes) and to moderate potential damages, to take advantage of opportunities or face the consequences. Adaptation reduces the adverse impacts of climate change and enhance beneficial impacts, but will not prevent substantial cost that are produced by all damages. The performances require adaptation actions. These are defined and implemented at national, regional or local levels since many of the impacts and vulnerabilities depend on the particular economic, geographic and social circumstances of each country or region. We will present some adaptation strategies at national and local level and revise some cases of its implementation in several vulnerable areas. However, adaptation to climate change must be closely related to mitigation policies because the degree of change planned in different climatic variables is a function of the concentration levels that are achieved

  8. Adaptation Strategies for Global Environmental Change

    NASA Astrophysics Data System (ADS)

    Ojima, D. S.; Corell, R.

    2007-12-01

    The global environmental challenges society faces today are unheralded due to the pace at which human activities are affecting the earth system. The rates of energy consumption, nitrogen use and production, and water use increases each year leading to greater global environmental changes affecting warming of the earth system and loss of ecosystem services. The challenge we face today as a society is the manner and speed at which we can adapt to these changes affecting the ecosystem services we depend upon. Innovative strategies are needed to develop the adaptive management tools to integrate the sectors and science necessary to deal with the complexity of effects. Developing strategies to better guide decision making related to climate change trends into changing weather patterns at meaningful temporal and spatial scales are needed, observations and prognostic analyses of climate related triggers of threshold events in ecosystem dynamics, and transfer of knowledge between science, technology, and decision makers. These strategies need to better integrate science (physical, biological, and social knowledge), engineering, policy, and economics interests to create a framework to develop strategies for adaptation and mitigation to global change and to create bridges with institutions and organizations that deal with these issues as a governmental agency or private sector enterprise.

  9. Climate adaptation strategy for natural resources released

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2013-04-01

    The National Fish, Wildlife, and Plants Climate Adaptation Strategy, released on 26 March by the Obama administration, calls for a series of measures to help public and private decision makers better address the effects of climate change on living natural resources. The measures include conserving habitat to support healthy fish, wildlife, and plant populations and ecosystem functions; managing species and habitats to protect ecosystem functions and provide sustainable commercial, subsistence, recreational, and cultural use; increasing knowledge and information about effects on and responses of fish, wildlife, and plants; and reducing nonclimate stressors to help fish, wildlife, plants, and ecosystems adapt.

  10. Adaptive Strategies for Materials Design using Uncertainties.

    PubMed

    Balachandran, Prasanna V; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-21

    We compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young's (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material with desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don't. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties.

  11. An adaptive strategy for active debris removal

    NASA Astrophysics Data System (ADS)

    White, Adam E.; Lewis, Hugh G.

    2014-04-01

    Many parameters influence the evolution of the near-Earth debris population, including launch, solar, explosion and mitigation activities, as well as other future uncertainties such as advances in space technology or changes in social and economic drivers that effect the utilisation of space activities. These factors lead to uncertainty in the long-term debris population. This uncertainty makes it difficult to identify potential remediation strategies, involving active debris removal (ADR), that will perform effectively in all possible future cases. Strategies that cannot perform effectively, because of this uncertainty, risk either not achieving their intended purpose, or becoming a hindrance to the efforts of spacecraft manufactures and operators to address the challenges posed by space debris. One method to tackle this uncertainty is to create a strategy that can adapt and respond to the space debris population. This work explores the concept of an adaptive strategy, in terms of the number of objects required to be removed by ADR, to prevent the low Earth orbit (LEO) debris population from growing in size. This was demonstrated by utilising the University of Southampton’s Debris Analysis and Monitoring Architecture to the Geosynchronous Environment (DAMAGE) tool to investigate ADR rates (number of removals per year) that change over time in response to the current space environment, with the requirement of achieving zero growth of the LEO population. DAMAGE was used to generate multiple Monte Carlo projections of the future LEO debris environment. Within each future projection, the debris removal rate was derived at five-year intervals, by a new statistical debris evolutionary model called the Computational Adaptive Strategy to Control Accurately the Debris Environment (CASCADE) model. CASCADE predicted the long-term evolution of the current DAMAGE population with a variety of different ADR rates in order to identify a removal rate that produced a zero net

  12. The impact of the great recession on community-based mental health organizations: an analysis of top managers' perceptions of the economic downturn's effects and adaptive strategies used to manage the consequences in Ohio.

    PubMed

    Sweeney, Helen Anne; Knudsen, Kraig

    2014-04-01

    The Great Recession of 2007-2009 adversely affected the financial stability of the community-based mental health infrastructure in Ohio. This paper presents survey results of the type of adaptive strategies used by Ohio community-based mental health organizations to manage the consequences of the economic downturn. Results were aggregated into geographical classifications of rural, mid-sized urban, and urban. Across all groups, respondents perceived, to varying degrees, that the Great Recession posed a threat to their organization's survival. Urban organizations were more likely to implement adaptive strategies to expand operations while rural and midsized urban organizations implemented strategies to enhance internal efficiencies.

  13. Adaptive Strategies in the Iterated Exchange Problem

    NASA Astrophysics Data System (ADS)

    Baraov, Arthur

    2011-03-01

    We argue for clear separation of the exchange problem from the exchange paradox to avoid confusion about the subject matter of these two distinct problems. The exchange problem in its current format belongs to the domain of optimal decision making—it doesn't make any sense as a game of competition. But it takes just a tiny modification in the statement of the problem to breathe new life into it and make it a practicable and meaningful game of competition. In this paper, we offer an explanation for paradoxical priors and discuss adaptive strategies for both the house and the player in the restated exchange problem.

  14. Adaptive Strategies for Materials Design using Uncertainties

    NASA Astrophysics Data System (ADS)

    Balachandran, Prasanna V.; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-01

    We compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young’s (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material with desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don’t. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties.

  15. Adaptive Strategies for Materials Design using Uncertainties

    PubMed Central

    Balachandran, Prasanna V.; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-01

    We compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young’s (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material with desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don’t. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties. PMID:26792532

  16. Adaptive strategies for materials design using uncertainties

    DOE PAGES

    Balachandran, Prasanna V.; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-21

    Here, we compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young’s (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material withmore » desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don’t. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties.« less

  17. Biometeorology - a science supporting adaptation strategies

    NASA Astrophysics Data System (ADS)

    Matzarakis, A.; Cegnar, T.

    2010-09-01

    Biometeorology as an interdisciplinary science deals with the interactions between atmospheric processes and living organisms (plants, animals and humans). If and in what way weather and climate affect the well-being of all the living creatures? This is the most important question biometeorology is answering. The International Society of Biometeorology (ISB) has built an international forum for the promotion of interdisciplinary collaboration between meteorologists, health professionals, biologists, climatologists, ecologists and other scientists. The Society acts as a community of scientists with similar interests, and fulfills an important role in providing information, expertise and advice for international organizations requiring this assistance. The ISB represents the most comprehensive organization, which brings together people with expertise in these areas. Another specific aim of the ISB is the stimulation of research. Therefore, groups of members are working on several topics organized in commissions for specific targets. The recent five commissions are working in the several fields including climate change issues. Some of examples will be presented, which have been initiated by the members of the ISB and how they can be included as a solid scientific basis to develop efficient adaptation strategies. One such example is a project combining natural and social sciences (in the fields of cooperation processes, tourism analysis and strategy, weather and climate change analysis, information and communication and knowledge transfer) in a transdisciplinary approach that includes players from tourism policy and business and which focuses on the North Sea Coast and the Black Forest. The project "Climate trends and sustainable development of tourism in coastal and mountain range regions was divided into four phases - diagnosis, assessment, strategy/design of solutions, and evaluation - where scientific subprojects and practical partners meet regularly to discuss the

  18. [Individual adaptation strategy under extreme environmental conditions in humans].

    PubMed

    Soroko, S I; Aldasheva, A A

    2012-01-01

    Starting from the researches of I.M. Sechenov, I.P. Pavlov, A.A. Uchtomskii, the Russian psychophysiological school considers adaptation in connection with the biological and social origin of a man as the integrated, coordinated and self-controlled human organism's reaction to maintain the vital functions in the constantly changing environmental conditions. On the base of well-known systemic-dynamic methodology and scrutinizing the issue of man and environment interaction V.I. Medvedev added to the theory of man's adaptation the activity paradigm that enable to uncover the distinctive features of professional activities in various environment conditions. The theoretical and practical investigations based on the activity methodology gave the opportunity to find out the new principles of interaction between man and environment and on the strategy of adaptive behavior. From this investigations one could see that the main characteristic of interaction "man-environment" is that man represents proactive side, man simulate different adaptation strategies using both genetically-fixed and acquired mechanisms of adaptive behavior. PMID:23393785

  19. Paradigms for adaptive statistical information designs: practical experiences and strategies.

    PubMed

    Wang, Sue-Jane; Hung, H M James; O'Neill, Robert

    2012-11-10

    In the last decade or so, interest in adaptive design clinical trials has gradually been directed towards their use in regulatory submissions by pharmaceutical drug sponsors to evaluate investigational new drugs. Methodological advances of adaptive designs are abundant in the statistical literature since the 1970s. The adaptive design paradigm has been enthusiastically perceived to increase the efficiency and to be more cost-effective than the fixed design paradigm for drug development. Much interest in adaptive designs is in those studies with two-stages, where stage 1 is exploratory and stage 2 depends upon stage 1 results, but where the data of both stages will be combined to yield statistical evidence for use as that of a pivotal registration trial. It was not until the recent release of the US Food and Drug Administration Draft Guidance for Industry on Adaptive Design Clinical Trials for Drugs and Biologics (2010) that the boundaries of flexibility for adaptive designs were specifically considered for regulatory purposes, including what are exploratory goals, and what are the goals of adequate and well-controlled (A&WC) trials (2002). The guidance carefully described these distinctions in an attempt to minimize the confusion between the goals of preliminary learning phases of drug development, which are inherently substantially uncertain, and the definitive inference-based phases of drug development. In this paper, in addition to discussing some aspects of adaptive designs in a confirmatory study setting, we underscore the value of adaptive designs when used in exploratory trials to improve planning of subsequent A&WC trials. One type of adaptation that is receiving attention is the re-estimation of the sample size during the course of the trial. We refer to this type of adaptation as an adaptive statistical information design. Specifically, a case example is used to illustrate how challenging it is to plan a confirmatory adaptive statistical information

  20. Adaptive versus nonadaptive strategies for quantum channel discrimination

    SciTech Connect

    Harrow, Aram W.; Hassidim, Avinatan; Leung, Debbie W.; Watrous, John

    2010-03-15

    We provide a simple example that illustrates the advantage of adaptive over nonadaptive strategies for quantum channel discrimination. In particular, we give a pair of entanglement-breaking channels that can be perfectly discriminated by means of an adaptive strategy that requires just two channel evaluations, but for which no nonadaptive strategy can give a perfect discrimination using any finite number of channel evaluations.

  1. [Adaptive strategies and adaptation after participation in a education program after a first coronary event].

    PubMed

    Henrichon, Carole; Robichaud-Ekstrand, Sylvie

    2002-09-01

    This descriptive correlational study compares adaptive strategies and adaptation according to participation to an outpatient education program "A vous de jouer". Participants more frequently use seeking social support strategies, and eating less fat, participating in physical activity, managing stress behaviors and returning to work. Distancing/escape avoidance strategies are negatively correlated with healthy life style habits, whereas positive reappraisal/problem solving, and seeking social support strategies are positively associated. Positive reappraisal/problem solving, program participation, and the non-use of distancing/escape avoidance strategies, predict adaptation. The use of these adaptive strategies and behaviors is therefore advantageous to coronary patients.

  2. A holistic strategy for adaptive land management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adaptive management is widely applied to natural resources management. Adaptive management can be generally defined as an iterative decision-making process that incorporates formulation of management objectives, actions designed to address these objectives, monitoring of results, and repeated adapta...

  3. Turnaround Management Strategies: The Adaptive Model and the Constructive Model. ASHE 1983 Annual Meeting Paper.

    ERIC Educational Resources Information Center

    Chaffee, Ellen E.

    The use of two management strategies by 14 liberal arts and comprehensive colleges attempting to recover from serious financial decline during 1973-1976 were studied. The adaptive model of strategy, based on resource dependence, involves managing demands in order to satisfy critical-resource providers. The constructive model of strategy, based on…

  4. Adaptive control strategies for flexible robotic arm

    NASA Technical Reports Server (NTRS)

    Bialasiewicz, Jan T.

    1993-01-01

    The motivation of this research came about when a neural network direct adaptive control scheme was applied to control the tip position of a flexible robotic arm. Satisfactory control performance was not attainable due to the inherent non-minimum phase characteristics of the flexible robotic arm tip. Most of the existing neural network control algorithms are based on the direct method and exhibit very high sensitivity if not unstable closed-loop behavior. Therefore a neural self-tuning control (NSTC) algorithm is developed and applied to this problem and showed promising results. Simulation results of the NSTC scheme and the conventional self-tuning (STR) control scheme are used to examine performance factors such as control tracking mean square error, estimation mean square error, transient response, and steady state response.

  5. Adapting MCH strategies for the nineties.

    PubMed

    Abel, R

    1994-01-01

    Brief overview was given for strategies in maternal and child health (MCH) in India that were used in the 1980s and adapted for the 1990s in the following areas: perinatal outcomes, empowerment of women, immunization, oral rehydration, adolescent girls, anthropometric measurement, health education, management, and coordination with nongovernmental organizations (NGOs). In order to assure a healthy baby weighing 2.5 kg, monitoring of maternal health is occurring. Iron and folic acid and tetanus toxoid vaccine are provided to pregnant mothers, and fetal growth is monitored. Training of traditional birth attendants and multipurpose health workers will contribute to clean deliveries and referral of complicated pregnancies. During the 1990s, women's health in addition to maternal health has received attention. The empowerment of women to care for themselves, to learn how to mix oral rehydration packets (ORS) at home, and to receive the knowledge and skills were deemed more important than the 1980s focus on the delivery system and inputs of MCH. An excellent cold chain for delivery of vaccines has been put in place, which provides the vehicle for the 1990s to maintain high vaccine coverage. The emphasis on oral rehydration in the 1990s will be on teaching mothers about the importance of ORS treatment of diarrhea. During the 1990s, educating the adolescent girl before she becomes married and pregnant will be the focus. Greater emphasis will be placed on stunting or height for age measurements, as a measure of long term nutritional change; age weight for height for measurement of wasting; and maternal nutritional monitoring of arm circumference. Sustained health education, more media exposure to disease conditions and treatment, and social marketing in health will be better coordinated and more cost effective. Accountability for manpower, materials, and money will be in place within management. Management will focus on motivation and training, and other, newer management

  6. Adapting MCH strategies for the nineties.

    PubMed

    Abel, R

    1994-01-01

    Brief overview was given for strategies in maternal and child health (MCH) in India that were used in the 1980s and adapted for the 1990s in the following areas: perinatal outcomes, empowerment of women, immunization, oral rehydration, adolescent girls, anthropometric measurement, health education, management, and coordination with nongovernmental organizations (NGOs). In order to assure a healthy baby weighing 2.5 kg, monitoring of maternal health is occurring. Iron and folic acid and tetanus toxoid vaccine are provided to pregnant mothers, and fetal growth is monitored. Training of traditional birth attendants and multipurpose health workers will contribute to clean deliveries and referral of complicated pregnancies. During the 1990s, women's health in addition to maternal health has received attention. The empowerment of women to care for themselves, to learn how to mix oral rehydration packets (ORS) at home, and to receive the knowledge and skills were deemed more important than the 1980s focus on the delivery system and inputs of MCH. An excellent cold chain for delivery of vaccines has been put in place, which provides the vehicle for the 1990s to maintain high vaccine coverage. The emphasis on oral rehydration in the 1990s will be on teaching mothers about the importance of ORS treatment of diarrhea. During the 1990s, educating the adolescent girl before she becomes married and pregnant will be the focus. Greater emphasis will be placed on stunting or height for age measurements, as a measure of long term nutritional change; age weight for height for measurement of wasting; and maternal nutritional monitoring of arm circumference. Sustained health education, more media exposure to disease conditions and treatment, and social marketing in health will be better coordinated and more cost effective. Accountability for manpower, materials, and money will be in place within management. Management will focus on motivation and training, and other, newer management

  7. Analyzing Hedges in Verbal Communication: An Adaptation-Based Approach

    ERIC Educational Resources Information Center

    Wang, Yuling

    2010-01-01

    Based on Adaptation Theory, the article analyzes the production process of hedges. The procedure consists of the continuous making of choices in linguistic forms and communicative strategies. These choices are made just for adaptation to the contextual correlates. Besides, the adaptation process is dynamic, intentional and bidirectional.

  8. A holistic strategy for adaptive land management

    USGS Publications Warehouse

    Herrick, Jeffrey E.; Duniway, Michael C.; Pyke, David A.; Bestelmeyer, Brandon T.; Wills, Skye A.; Brown, Joel R.; Karl, Jason W.; Havstad, Kris M.

    2012-01-01

    Adaptive management is widely applied to natural resources management (Holling 1973; Walters and Holling 1990). Adaptive management can be generally defined as an iterative decision-making process that incorporates formulation of management objectives, actions designed to address these objectives, monitoring of results, and repeated adaptation of management until desired results are achieved (Brown and MacLeod 1996; Savory and Butterfield 1999). However, adaptive management is often criticized because very few projects ever complete more than one cycle, resulting in little adaptation and little knowledge gain (Lee 1999; Walters 2007). One significant criticism is that adaptive management is often used as a justification for undertaking actions with uncertain outcomes or as a surrogate for the development of specific, measurable indicators and monitoring programs (Lee 1999; Ruhl 2007).

  9. Adaptation and optimal chemotactic strategy for {ital E. coli}

    SciTech Connect

    Strong, S.P.; Bialek, William; Koberle, R. Freedman, B.

    1998-04-01

    Extending the classic works of Berg and Purcell on the biophysics of bacterial chemotaxis, we find the optimal chemotactic strategy for the peritrichous bacterium {ital E. coli} in the high and low signal to noise ratio limits. The optimal strategy depends on properties of the environment and properties of the individual bacterium, and is therefore highly adaptive. We review experiments relevant to testing both the form of the proposed strategy and its adaptability, and propose extensions of them which could test the limits of the adaptability in this simplest sensory processing system. {copyright} {ital 1998} {ital The American Physical Society}

  10. New communication schemes based on adaptive synchronization

    NASA Astrophysics Data System (ADS)

    Yu, Wenwu; Cao, Jinde; Wong, Kwok-Wo; Lü, Jinhu

    2007-09-01

    In this paper, adaptive synchronization with unknown parameters is discussed for a unified chaotic system by using the Lyapunov method and the adaptive control approach. Some communication schemes, including chaotic masking, chaotic modulation, and chaotic shift key strategies, are then proposed based on the modified adaptive method. The transmitted signal is masked by chaotic signal or modulated into the system, which effectively blurs the constructed return map and can resist this return map attack. The driving system with unknown parameters and functions is almost completely unknown to the attackers, so it is more secure to apply this method into the communication. Finally, some simulation examples based on the proposed communication schemes and some cryptanalysis works are also given to verify the theoretical analysis in this paper.

  11. Climate change adaptation strategies for resource management and conservation planning.

    PubMed

    Lawler, Joshua J

    2009-04-01

    Recent rapid changes in the Earth's climate have altered ecological systems around the globe. Global warming has been linked to changes in physiology, phenology, species distributions, interspecific interactions, and disturbance regimes. Projected future climate change will undoubtedly result in even more dramatic shifts in the states of many ecosystems. These shifts will provide one of the largest challenges to natural resource managers and conservation planners. Managing natural resources and ecosystems in the face of uncertain climate requires new approaches. Here, the many adaptation strategies that have been proposed for managing natural systems in a changing climate are reviewed. Most of the recommended approaches are general principles and many are tools that managers are already using. What is new is a turning toward a more agile management perspective. To address climate change, managers will need to act over different spatial and temporal scales. The focus of restoration will need to shift from historic species assemblages to potential future ecosystem services. Active adaptive management based on potential future climate impact scenarios will need to be a part of everyday operations. And triage will likely become a critical option. Although many concepts and tools for addressing climate change have been proposed, key pieces of information are still missing. To successfully manage for climate change, a better understanding will be needed of which species and systems will likely be most affected by climate change, how to preserve and enhance the evolutionary capacity of species, how to implement effective adaptive management in new systems, and perhaps most importantly, in which situations and systems will the general adaptation strategies that have been proposed work and how can they be effectively applied.

  12. Adaptive strategies for cumulative cultural learning.

    PubMed

    Ehn, Micael; Laland, Kevin

    2012-05-21

    The demographic and ecological success of our species is frequently attributed to our capacity for cumulative culture. However, it is not yet known how humans combine social and asocial learning to generate effective strategies for learning in a cumulative cultural context. Here we explore how cumulative culture influences the relative merits of various pure and conditional learning strategies, including pure asocial and social learning, critical social learning, conditional social learning and individual refiner strategies. We replicate the Rogers' paradox in the cumulative setting. However, our analysis suggests that strategies that resolved Rogers' paradox in a non-cumulative setting may not necessarily evolve in a cumulative setting, thus different strategies will optimize cumulative and non-cumulative cultural learning.

  13. [Coping strategies in adaptation of higher education students].

    PubMed

    das Neves Mira Freitas, Helena Cristina

    2007-01-01

    The adjustment to higher education can be understood as a multidimensional process, which requires by the student a development of adaptive skills to a new and dynamic context in itself. To meet these challenges students have to develop effective coping strategies, enabling them to be adapted to the context. The school has a key role in the help it can give to these young people, in order to adapt effectively.

  14. [Coping strategies in adaptation of higher education students].

    PubMed

    das Neves Mira Freitas, Helena Cristina

    2007-01-01

    The adjustment to higher education can be understood as a multidimensional process, which requires by the student a development of adaptive skills to a new and dynamic context in itself. To meet these challenges students have to develop effective coping strategies, enabling them to be adapted to the context. The school has a key role in the help it can give to these young people, in order to adapt effectively. PMID:18372532

  15. Strategies for risk-adapted therapy in myeloma.

    PubMed

    Fonseca, Rafael

    2007-01-01

    It is clear that the clinical heterogeneity of multiple myeloma (MM) is dictated, in large part, by disease biology, predominantly genetics.(1) As novel therapeutics have emerged, and augmented our treatment armamentarium against the disease, it is increasingly important to introduce a risk-adapted approach for the optimal management of patients.(2) The selection of ideal candidates for high-dose chemotherapy with stem cell support (HDT) and maintenance will undoubtedly have to include baseline knowledge of the genetic nature of the individual. The limited duration of responses after HDT for patients with t(4;14)(p16;q32), t(14;16)(q32;q23) and 17p13 deletions highlight the need to develop a risk-adapted treatment strategy.(3)(-)(5) Novel ways of determining outcome such as the use of gene expression profiling have demonstrated differentiating capabilities not previously observed.(6) Likewise, the order of introduction of novel therapeutic agents (during induction and in the relapsing patient) will be potentially directed by similar information. As we have previously stated, MM is not only multiple but also "many."(7) Accordingly, treatment strategies will be tailored based on risk determination, genetic composition and host features.

  16. Adaptive finite element strategies for shell structures

    NASA Technical Reports Server (NTRS)

    Stanley, G.; Levit, I.; Stehlin, B.; Hurlbut, B.

    1992-01-01

    The present paper extends existing finite element adaptive refinement (AR) techniques to shell structures, which have heretofore been neglected in the AR literature. Specific challenges in applying AR to shell structures include: (1) physical discontinuities (e.g., stiffener intersections); (2) boundary layers; (3) sensitivity to geometric imperfections; (4) the sensitivity of most shell elements to mesh distortion, constraint definition and/or thinness; and (5) intrinsic geometric nonlinearity. All of these challenges but (5) are addressed here.

  17. Beyond Brainstorming: Exploring Climate Change Adaptation Strategies

    NASA Astrophysics Data System (ADS)

    Garfin, Gregg; Jacobs, Katharine; Buizer, James

    2008-06-01

    Climate Change Adaptation for Water Managers; Oracle, Arizona, 4-5 February 2008; The most visible manifestation of climate change in the American Southwest is its effects on water resources. Since 1999, the region's water supplies and major rivers have been tested by burgeoning population growth and drought. Model projections suggest increasing drought severity and duration due to rising temperatures, increased evapotranspiration, and enhanced atmospheric circulation from the tropics (Hadley circulation).

  18. The Contextual Adaptation of English Teachers' Questioning Strategies

    ERIC Educational Resources Information Center

    Xi, Hong-mei; Li, Wang-zi; Lei, Ping

    2010-01-01

    In order to guarantee an interactive classroom atmosphere, English teachers pay much attention to the questioning strategies when they use question-answer teaching method. This paper makes a comprehensive analysis on English teachers' questioning strategies from the perspective of adaptation theory. It shows that the utilization of teachers'…

  19. Exposure to stressful environments - Strategy of adaptive responses

    NASA Technical Reports Server (NTRS)

    Farhi, Leon E.

    1991-01-01

    Stresses such as hypoxia, water lack, and heat exposure can produce strains in more than a single organ system, in turn stimulating the body to adapt in multiple ways. Nevertheless, a general strategy of the various adaptive responses emerges when the challenges are divided into three groups: (1) conditions that affect the supply of essential molecules, (2) stresses that prevent the body from regulating properly the output of waste products such as CO2 and heat, and (3) environments that disrupt body transport systems. Problems may arise when there is a conflict between two stresses requiring conflicting adaptive changes. An alternative to adaptation, creation of microenvironment, is often favored by the animal.

  20. Test Information Targeting Strategies for Adaptive Multistage Testing Designs.

    ERIC Educational Resources Information Center

    Luecht, Richard M.; Burgin, William

    Adaptive multistage testlet (MST) designs appear to be gaining popularity for many large-scale computer-based testing programs. These adaptive MST designs use a modularized configuration of preconstructed testlets and embedded score-routing schemes to prepackage different forms of an adaptive test. The conditional information targeting (CIT)…

  1. Focus on climate projections for adaptation strategies

    NASA Astrophysics Data System (ADS)

    Feijt, Arnout; Appenzeller, Christof; Siegmund, Peter; von Storch, Hans

    2016-01-01

    Most papers in this focus issue on ‘climate and climate impact projections for adaptation strategies’ are solicited by the guest editorial team and originate from a cluster of projects that were initiated 5 years ago. These projects aimed to provide climate change and climate change adaptation information for a wide range of societal areas for the lower parts of the deltas of the Rhine and Meuse rivers, and particularly for the Netherlands. The papers give an overview of our experiences, methods, approaches, results and surprises in the process to developing scientifically underpinned climate products and services for various clients. Although the literature on interactions between society and climate science has grown over the past decade both with respect to policy-science framing in post-normal science (Storch et al 2011 J. Environ. Law Policy 1 1-15, van der Sluijs 2012 Nature and Culture 7 174-195), user-science framing (Berkhout et al 2014 Regional Environ. Change 14 879-93) and joint knowledge production (Hegger et al 2014 Regional Environ. Change 14 1049-62), there is still a lot to gain. With this focus issue we want to contribute to best practices in this quickly moving field between science and society.

  2. Parallel Programming Strategies for Irregular Adaptive Applications

    NASA Technical Reports Server (NTRS)

    Biswas, Rupak; Biegel, Bryan (Technical Monitor)

    2001-01-01

    Achieving scalable performance for dynamic irregular applications is eminently challenging. Traditional message-passing approaches have been making steady progress towards this goal; however, they suffer from complex implementation requirements. The use of a global address space greatly simplifies the programming task, but can degrade the performance for such computations. In this work, we examine two typical irregular adaptive applications, Dynamic Remeshing and N-Body, under competing programming methodologies and across various parallel architectures. The Dynamic Remeshing application simulates flow over an airfoil, and refines localized regions of the underlying unstructured mesh. The N-Body experiment models two neighboring Plummer galaxies that are about to undergo a merger. Both problems demonstrate dramatic changes in processor workloads and interprocessor communication with time; thus, dynamic load balancing is a required component.

  3. Adaptive Nonlinear Signal Approximation Using Bacterial Foraging Strategy

    NASA Astrophysics Data System (ADS)

    Kumar, Naik Manoj; Rutuparna, Panda

    Uniform approximation of signals has been an area of interest for researchers working in different disciplines of science and engineering. This paper presents an adaptive algorithm based on E. coli bacteria foraging strategy (EBFS) for uniform approximation of signals by linear combinations of shifted nonlinear basis functions. New class of nonlinear basis functions has been derived from a sigmoid function. The weight factor of the newly proposed nonlinear basis functions has been optimized by using the EBFS to minimize the mean square error. Different test signals are considered for validation of the present technique. Results are also compared with Genetic algorithm approach. The proposed technique could also be useful in fractional signal processing applications.

  4. Adaptive mating strategies and the problem of mate retention.

    PubMed

    Husárová, Barbara

    2005-09-01

    "Adaptations" are evolved solutions to the problems posed by survival and reproduction. The evolutionary psychologists believe that as well as the physical adaptations so the adaptations in human mind evolved, called "strategies". The "mating strategies" are adaptive solutions to successful mating. The mating strategies, designed to preserve access to a mate by preventing encroachment of intrasexual rivals and by preventing a mate from defecting from the mateship for a prospective better partner, are called "mate guarding strategies". The previous research found that humans do use a wide variety of behavioural tactics of mate guarding, ranging from vigilance to violence. Our research group explores the type and the intensity of behavioural tactics of mate guarding used in several contexts. Presently, the link between the woman's fertility status across her menstrual cycle and the man's mate guarding is examined. Discussing the preliminary results, a more intensive man's mate guarding of his partner around the ovulation when her fertility peaks may be assumed. These outcomes could be explained as an adaptive prevention to shift in woman's preferences to increase her extra-pair sexual attempts and following to a possible genetic cuckoldry at that most fertile time.

  5. Adaptive mesh strategies for the spectral element method

    NASA Technical Reports Server (NTRS)

    Mavriplis, Catherine

    1992-01-01

    An adaptive spectral method was developed for the efficient solution of time dependent partial differential equations. Adaptive mesh strategies that include resolution refinement and coarsening by three different methods are illustrated on solutions to the 1-D viscous Burger equation and the 2-D Navier-Stokes equations for driven flow in a cavity. Sharp gradients, singularities, and regions of poor resolution are resolved optimally as they develop in time using error estimators which indicate the choice of refinement to be used. The adaptive formulation presents significant increases in efficiency, flexibility, and general capabilities for high order spectral methods.

  6. Cultural adaptation of preschool PATHS (Promoting Alternative Thinking Strategies) curriculum for Pakistani children.

    PubMed

    Inam, Ayesha; Tariq, Pervaiz N; Zaman, Sahira

    2015-06-01

    Cultural adaptation of evidence-based programmes has gained importance primarily owing to its perceived impact on the established effectiveness of a programme. To date, many researchers have proposed different frameworks for systematic adaptation process. This article presents the cultural adaptation of preschool Promoting Alternative Thinking Strategies (PATHS) curriculum for Pakistani children using the heuristic framework of adaptation (Barrera & Castro, 2006). The study was completed in four steps: information gathering, preliminary adaptation design, preliminary adaptation test and adaptation refinement. Feedbacks on programme content suggested universality of the core programme components. Suggested changes were mostly surface structure: language, presentation of materials, conceptual equivalence of concepts, training needs of implementation staff and frequency of programme delivery. In-depth analysis was done to acquire cultural equivalence. Pilot testing of the outcome measures showed strong internal consistency. The results were further discussed with reference to similar work undertaken in other cultures.

  7. Adaptive Replacement Strategies for MOEA/D.

    PubMed

    Wang, Zhenkun; Zhang, Qingfu; Zhou, Aimin; Gong, Maoguo; Jiao, Licheng

    2016-02-01

    Multiobjective evolutionary algorithms based on decomposition (MOEA/D) decompose a multiobjective optimization problem into a set of simple optimization subproblems and solve them in a collaborative manner. A replacement scheme, which assigns a new solution to a subproblem, plays a key role in balancing diversity and convergence in MOEA/D. This paper proposes a global replacement scheme which assigns a new solution to its most suitable subproblems. We demonstrate that the replacement neighborhood size is critical for population diversity and convergence, and develop an approach for adjusting this size dynamically. A steady-state algorithm and a generational one with this approach have been designed and experimentally studied. The experimental results on a number of test problems have shown that the proposed algorithms have some advantages. PMID:25826813

  8. Adaptive Insecure Attachment and Resource Control Strategies during Middle Childhood

    ERIC Educational Resources Information Center

    Chen, Bin-Bin; Chang, Lei

    2012-01-01

    By integrating the life history theory of attachment with resource control theory, the current study examines the hypothesis that insecure attachment styles reorganized in middle childhood are alternative adaptive strategies used to prepare for upcoming competition with the peer group. A sample of 654 children in the second through seventh grades…

  9. Exposure to Stressful Environments: Strategy of Adaptive Responses

    NASA Technical Reports Server (NTRS)

    Farhi, Leon E.

    1991-01-01

    Any new natural environment may generate a number of stresses (such as hypoxia, water lack, and heat exposure), each of which can produce strains in more than a single organ system. Every strain may in turn stimulate the body to adapt in multiple ways. Nevertheless, a general strategy of the various adaptive responses emerges when the challenges are divided into three groups. The first category includes conditions that affect the supply of essential molecules, while the second is made up by those stresses that prevent the body from regulating properly the output of waste products, such as CO2 and heat. In both classes, there is a small number of responses, similar in principle, regardless of the specific situation. The third unit is created by environments that disrupt body transport systems. Problems may arise when there is a conflict between two stresses requiring conflicting adaptive changes. An alternative to adaptation, creation of micro-environment, is often favored by the animal.

  10. Assessment of the effectiveness of flood adaptation strategies for HCMC

    NASA Astrophysics Data System (ADS)

    Lasage, R.; Veldkamp, T. I. E.; de Moel, H.; Van, T. C.; Phi, H. L.; Vellinga, P.; Aerts, J. C. J. H.

    2014-06-01

    Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reduction measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea-level rise and socio-economic developments on flood risk for the flood-prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet proofing of buildings and elevating roads and buildings). A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. The model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in expected annual damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea-level scenarios and land-use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5% and 5%. The results of this modelling study indicate that the current flood risk in District 4 is USD 0.31 million per year, increasing up to USD 0.78 million per year in 2100. The net present value and benefit-cost ratios using a discount rate of 5 % range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5% leads to an increase in both net present value and benefit-cost ratio. The adaptation strategies wet-proofing and dry-proofing generate the best results using these economic indicators. The information

  11. Feedback in Videogame-Based Adaptive Training

    ERIC Educational Resources Information Center

    Rivera, Iris Daliz

    2010-01-01

    The field of training has been changing rapidly due to advances in technology such as videogame-based adaptive training. Videogame-based adaptive training has provided flexibility and adaptability for training in cost-effective ways. Although this method of training may have many benefits for the trainee, current research has not kept up to pace…

  12. Adaptive robust controller based on integral sliding mode concept

    NASA Astrophysics Data System (ADS)

    Taleb, M.; Plestan, F.

    2016-09-01

    This paper proposes, for a class of uncertain nonlinear systems, an adaptive controller based on adaptive second-order sliding mode control and integral sliding mode control concepts. The adaptation strategy solves the problem of gain tuning and has the advantage of chattering reduction. Moreover, limited information about perturbation and uncertainties has to be known. The control is composed of two parts: an adaptive one whose objective is to reject the perturbation and system uncertainties, whereas the second one is chosen such as the nominal part of the system is stabilised in zero. To illustrate the effectiveness of the proposed approach, an application on an academic example is shown with simulation results.

  13. Heteroresistance at the Single-Cell Level: Adapting to Antibiotic Stress through a Population-Based Strategy and Growth-Controlled Interphenotypic Coordination

    PubMed Central

    Wang, Xiaorong; Kang, Yu; Luo, Chunxiong; Zhao, Tong; Liu, Lin; Jiang, Xiangdan; Fu, Rongrong; An, Shuchang; Chen, Jichao; Jiang, Ning; Ren, Lufeng; Wang, Qi; Baillie, J. Kenneth; Gao, Zhancheng; Yu, Jun

    2014-01-01

    ABSTRACT Heteroresistance refers to phenotypic heterogeneity of microbial clonal populations under antibiotic stress, and it has been thought to be an allocation of a subset of “resistant” cells for surviving in higher concentrations of antibiotic. The assumption fits the so-called bet-hedging strategy, where a bacterial population “hedges” its “bet” on different phenotypes to be selected by unpredicted environment stresses. To test this hypothesis, we constructed a heteroresistance model by introducing a blaCTX-M-14 gene (coding for a cephalosporin hydrolase) into a sensitive Escherichia coli strain. We confirmed heteroresistance in this clone and that a subset of the cells expressed more hydrolase and formed more colonies in the presence of ceftriaxone (exhibited stronger “resistance”). However, subsequent single-cell-level investigation by using a microfluidic device showed that a subset of cells with a distinguishable phenotype of slowed growth and intensified hydrolase expression emerged, and they were not positively selected but increased their proportion in the population with ascending antibiotic concentrations. Therefore, heteroresistance—the gradually decreased colony-forming capability in the presence of antibiotic—was a result of a decreased growth rate rather than of selection for resistant cells. Using a mock strain without the resistance gene, we further demonstrated the existence of two nested growth-centric feedback loops that control the expression of the hydrolase and maximize population growth in various antibiotic concentrations. In conclusion, phenotypic heterogeneity is a population-based strategy beneficial for bacterial survival and propagation through task allocation and interphenotypic collaboration, and the growth rate provides a critical control for the expression of stress-related genes and an essential mechanism in responding to environmental stresses. PMID:24520060

  14. Adaptive local routing strategy on a scale-free network

    NASA Astrophysics Data System (ADS)

    Liu, Feng; Zhao, Han; Li, Ming; Ren, Feng-Yuan; Zhu, Yan-Bo

    2010-04-01

    Due to the heterogeneity of the structure on a scale-free network, making the betweennesses of all nodes become homogeneous by reassigning the weights of nodes or edges is very difficult. In order to take advantage of the important effect of high degree nodes on the shortest path communication and preferentially deliver packets by them to increase the probability to destination, an adaptive local routing strategy on a scale-free network is proposed, in which the node adjusts the forwarding probability with the dynamical traffic load (packet queue length) and the degree distribution of neighbouring nodes. The critical queue length of a node is set to be proportional to its degree, and the node with high degree has a larger critical queue length to store and forward more packets. When the queue length of a high degree node is shorter than its critical queue length, it has a higher probability to forward packets. After higher degree nodes are saturated (whose queue lengths are longer than their critical queue lengths), more packets will be delivered by the lower degree nodes around them. The adaptive local routing strategy increases the probability of a packet finding its destination quickly, and improves the transmission capacity on the scale-free network by reducing routing hops. The simulation results show that the transmission capacity of the adaptive local routing strategy is larger than that of three previous local routing strategies.

  15. Controls on Extreme Droughts and Adaptation Strategies in Semiarid Regions

    NASA Astrophysics Data System (ADS)

    Scanlon, B. R.; Cook, C.; Fernando, D. N.; LeBlanc, M.

    2012-12-01

    Increasing vulnerability to droughts with reduced per capita water storage, particularly in semiarid regions, underscores the need for predictive understanding of drought controls and development of adaptation strategies for water resources management. In this study we evaluate causes of major droughts in southwest and southcentral US (California and Texas) and southeast Australia (Murray Darling Basin). Impacts of climate cycles (ENSO, PDO, AMO, NAO, IOD) and atmospheric circulation on drought initiation and persistence are examined. Effects of drought on surface water reservoir storage, groundwater storage, irrigation, and crop production are compared. Adaptation strategies being evaluated include water transfers among sectors, particularly from irrigated agriculture to other groups, increasing storage using managed aquifer recharge, water reuse, and development of new water sources (e.g. seawater desalination). It is critical to develop a broad portfolio of water sources to increase resilience to future droughts.

  16. Diversity of immune strategies explained by adaptation to pathogen statistics

    PubMed Central

    Mayer, Andreas; Mora, Thierry; Rivoire, Olivier; Walczak, Aleksandra M.

    2016-01-01

    Biological organisms have evolved a wide range of immune mechanisms to defend themselves against pathogens. Beyond molecular details, these mechanisms differ in how protection is acquired, processed, and passed on to subsequent generations—differences that may be essential to long-term survival. Here, we introduce a mathematical framework to compare the long-term adaptation of populations as a function of the pathogen dynamics that they experience and of the immune strategy that they adopt. We find that the two key determinants of an optimal immune strategy are the frequency and the characteristic timescale of the pathogens. Depending on these two parameters, our framework identifies distinct modes of immunity, including adaptive, innate, bet-hedging, and CRISPR-like immunities, which recapitulate the diversity of natural immune systems. PMID:27432970

  17. Adaptive strategies to climate change in Southern Malawi

    NASA Astrophysics Data System (ADS)

    Chidanti-Malunga, J.

    Climate change poses a big challenge to rural livelihoods in the Shire Valley area of Southern Malawi, where communities have depended almost entirely on rain-fed agriculture for generations. The Shire Valley area comprises of low-altitude dambo areas and uplands which have been the main agricultural areas. Since early to mid 1980s, the uplands have experienced prolonged droughts and poor rainfall distribution, while the dambos have experienced recurrent seasonal floods. This study assessed some of the adaptive strategies exercised by small-scale rural farmers in response to climate change in the Shire Valley. The methodology used in collecting information includes group discussions, household surveys in the area, secondary data, and field observations. The results show that small-scale rural farmers exercise a number of adaptive strategies in response to climate change. These adaptive strategies include: increased use of water resources for small-scale irrigation or wetland farming, mostly using simple delivery techniques; increased management of residual moisture; and increased alternative sources of income such as fishing and crop diversity. It was also observed that government promoted the use of portable motorized pumps for small-scale irrigation in order to mitigate the effects of climate change. However, these external interventions were not fully adopted; instead the farmers preferred local interventions which mostly had indigenous elements.

  18. Linking Federal, State, and Local Adaptation Strategies in New York (Invited)

    NASA Astrophysics Data System (ADS)

    Rosenzweig, C.

    2010-12-01

    New York City and New York State are leaders in adaptation in the U.S. In 2008 Mayor Bloomberg convened the NYC Climate Change Adaptation Task Force and the New York City Panel on Climate Change (NPCC). Also in 2008, the New York State Energy Research and Development Authority (NYSERDA) initiated the Integrated Assessment for Effective Climate Change Adaptation Strategies (ClimAID), to provide New York State decision-makers with cutting-edge information on its vulnerability to climate change and to facilitate the development of adaptation strategies informed by both local experience and scientific knowledge. The two efforts are working together to develop effective adaptation strategies across multiple jurisdictions. The New York Task Force consists of approximate 40 city, state, and federal agencies, regional public authorities, and private companies that operate, maintain, or regulate critical infrastructure in the region. The NPCC consisted of climate change and impacts scientists, and legal, insurance, and risk-management experts and served as the technical advisory body for the Mayor and the Task Force on issues related to climate change, impacts, and adaptation. In its 2010 report, the NPCC recommended adoption of a risk-based approach to climate change; creation of a monitoring program to track and analyze key climate change factors, impacts, and adaptation indicators; review of relevant standards and codes; inclusion of multiple layers of government and a wide range of public and private stakeholder experts to build buy-in; and formation of crucial partnerships for development of coordinated adaptation strategies. The task now is for these partnerships to create pilot programs that move adaptation from the planning phase to implementation; urban areas can provide critical ‘test-beds’ for such efforts.

  19. Multilevel Optimization Framework for Hierarchical Stiffened Shells Accelerated by Adaptive Equivalent Strategy

    NASA Astrophysics Data System (ADS)

    Wang, Bo; Tian, Kuo; Zhao, Haixin; Hao, Peng; Zhu, Tianyu; Zhang, Ke; Ma, Yunlong

    2016-09-01

    In order to improve the post-buckling optimization efficiency of hierarchical stiffened shells, a multilevel optimization framework accelerated by adaptive equivalent strategy is presented in this paper. Firstly, the Numerical-based Smeared Stiffener Method (NSSM) for hierarchical stiffened shells is derived by means of the numerical implementation of asymptotic homogenization (NIAH) method. Based on the NSSM, a reasonable adaptive equivalent strategy for hierarchical stiffened shells is developed from the concept of hierarchy reduction. Its core idea is to self-adaptively decide which hierarchy of the structure should be equivalent according to the critical buckling mode rapidly predicted by NSSM. Compared with the detailed model, the high prediction accuracy and efficiency of the proposed model is highlighted. On the basis of this adaptive equivalent model, a multilevel optimization framework is then established by decomposing the complex entire optimization process into major-stiffener-level and minor-stiffener-level sub-optimizations, during which Fixed Point Iteration (FPI) is employed to accelerate convergence. Finally, the illustrative examples of the multilevel framework is carried out to demonstrate its efficiency and effectiveness to search for the global optimum result by contrast with the single-level optimization method. Remarkably, the high efficiency and flexibility of the adaptive equivalent strategy is indicated by compared with the single equivalent strategy.

  20. Ensemble analysis of adaptive compressed genome sequencing strategies

    PubMed Central

    2014-01-01

    Background Acquiring genomes at single-cell resolution has many applications such as in the study of microbiota. However, deep sequencing and assembly of all of millions of cells in a sample is prohibitively costly. A property that can come to rescue is that deep sequencing of every cell should not be necessary to capture all distinct genomes, as the majority of cells are biological replicates. Biologically important samples are often sparse in that sense. In this paper, we propose an adaptive compressed method, also known as distilled sensing, to capture all distinct genomes in a sparse microbial community with reduced sequencing effort. As opposed to group testing in which the number of distinct events is often constant and sparsity is equivalent to rarity of an event, sparsity in our case means scarcity of distinct events in comparison to the data size. Previously, we introduced the problem and proposed a distilled sensing solution based on the breadth first search strategy. We simulated the whole process which constrained our ability to study the behavior of the algorithm for the entire ensemble due to its computational intensity. Results In this paper, we modify our previous breadth first search strategy and introduce the depth first search strategy. Instead of simulating the entire process, which is intractable for a large number of experiments, we provide a dynamic programming algorithm to analyze the behavior of the method for the entire ensemble. The ensemble analysis algorithm recursively calculates the probability of capturing every distinct genome and also the expected total sequenced nucleotides for a given population profile. Our results suggest that the expected total sequenced nucleotides grows proportional to log of the number of cells and proportional linearly with the number of distinct genomes. The probability of missing a genome depends on its abundance and the ratio of its size over the maximum genome size in the sample. The modified resource

  1. Domain Adaptation of Deformable Part-Based Models.

    PubMed

    Xu, Jiaolong; Ramos, Sebastian; Vázquez, David; López, Antonio M

    2014-12-01

    The accuracy of object classifiers can significantly drop when the training data (source domain) and the application scenario (target domain) have inherent differences. Therefore, adapting the classifiers to the scenario in which they must operate is of paramount importance. We present novel domain adaptation (DA) methods for object detection. As proof of concept, we focus on adapting the state-of-the-art deformable part-based model (DPM) for pedestrian detection. We introduce an adaptive structural SVM (A-SSVM) that adapts a pre-learned classifier between different domains. By taking into account the inherent structure in feature space (e.g., the parts in a DPM), we propose a structure-aware A-SSVM (SA-SSVM). Neither A-SSVM nor SA-SSVM needs to revisit the source-domain training data to perform the adaptation. Rather, a low number of target-domain training examples (e.g., pedestrians) are used. To address the scenario where there are no target-domain annotated samples, we propose a self-adaptive DPM based on a self-paced learning (SPL) strategy and a Gaussian Process Regression (GPR). Two types of adaptation tasks are assessed: from both synthetic pedestrians and general persons (PASCAL VOC) to pedestrians imaged from an on-board camera. Results show that our proposals avoid accuracy drops as high as 15 points when comparing adapted and non-adapted detectors. PMID:26353145

  2. Adaptation and Analysis of Motivated Strategies for Learning Questionnaire in the Chinese Setting

    ERIC Educational Resources Information Center

    Lee, John Chi-kin; Yin, Hongbiao; Zhang, Zhonghua

    2010-01-01

    This article reports the adaptation and analysis of Pintrich's Motivated Strategies for Learning Questionnaire (MSLQ) in Hong Kong. First, this study examined the psychometric qualities of the existing Chinese version of MSLQ (MSLQ-CV). Based on this examination, this study developed a revised Chinese version of MSLQ (MSLQ-RCV) for junior…

  3. 77 FR 2996 - National Fish, Wildlife, and Plants Climate Adaptation Strategy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... the Strategy in a May 24, 2011, notice of intent in the Federal Register (76 FR 30193). After we... Fish and Wildlife Service National Fish, Wildlife, and Plants Climate Adaptation Strategy AGENCY: Fish..., Wildlife, and Plants Climate Adaptation Strategy (Strategy). The purpose of the Strategy will be to...

  4. Predictor-Based Model Reference Adaptive Control

    NASA Technical Reports Server (NTRS)

    Lavretsky, Eugene; Gadient, Ross; Gregory, Irene M.

    2009-01-01

    This paper is devoted to robust, Predictor-based Model Reference Adaptive Control (PMRAC) design. The proposed adaptive system is compared with the now-classical Model Reference Adaptive Control (MRAC) architecture. Simulation examples are presented. Numerical evidence indicates that the proposed PMRAC tracking architecture has better than MRAC transient characteristics. In this paper, we presented a state-predictor based direct adaptive tracking design methodology for multi-input dynamical systems, with partially known dynamics. Efficiency of the design was demonstrated using short period dynamics of an aircraft. Formal proof of the reported PMRAC benefits constitute future research and will be reported elsewhere.

  5. Running training and adaptive strategies of locomotor-respiratory coordination.

    PubMed

    McDermott, William J; Van Emmerik, Richard E A; Hamill, Joseph

    2003-06-01

    It has been suggested that stronger coupling between locomotory and breathing rhythms may occur as a result of training in the particular movement pattern and also may reduce the perceived workload or metabolic cost of the movement. Research findings on human locomotor-respiratory coordination are equivocal, due in part to the fact that assessment techniques range in sensitivity to important aspects of coordination (e.g. temporal ordering of patterns, half-integer couplings and changes in frequency and phase coupling). An additional aspect that has not received much attention is the adaptability of this coordination to changes in task constraints. The current study investigated the effect of running training on the locomotor-respiratory coordination and the adaptive strategies observed across a wide range of walking and running speeds. Locomotor-respiratory coordination was evaluated by the strength and variability of both frequency and phase coupling patterns that subjects displayed within and across the speed conditions. Male subjects (five runners, five non-runners) locomoted at seven different treadmill speeds. Group results indicated no differences between runners and non-runners with respect to breathing parameters, stride parameters, as well as the strength and variability of the coupling at each speed. Individual results, however, showed that grouping subjects masks large individual differences and strategies across speeds. Coupling strategies indicated that runners show more stable dominant couplings across locomotory speeds than non-runners do. These findings suggest that running training does not change the strength of locomotor-respiratory coupling but rather how these systems adapt to changing speeds.

  6. Adaptive strategy for multi-user robotic rehabilitation games.

    PubMed

    Caurin, Glauco A P; Siqueira, Adriano A G; Andrade, Kleber O; Joaquim, Ricardo C; Krebs, Hermano I

    2011-01-01

    In this paper, we discuss a strategy for the adaptation of the "difficulty level" in games intended to include motor planning during robotic rehabilitation. We consider concurrently the motivation of the user and his/her performance in a Pong game. User motivation is classified in three levels (not motivated, well motivated and overloaded). User performance is measured as a combination of knowledge of results--achieved goals and score points in the game--and knowledge of performance--joint displacement, speed, aiming, user work, etc. Initial results of a pilot test with unimpaired healthy young volunteers are also presented showing a tendency for individualization of the parameter values.

  7. Adaptive strategy for multi-user robotic rehabilitation games.

    PubMed

    Caurin, Glauco A P; Siqueira, Adriano A G; Andrade, Kleber O; Joaquim, Ricardo C; Krebs, Hermano I

    2011-01-01

    In this paper, we discuss a strategy for the adaptation of the "difficulty level" in games intended to include motor planning during robotic rehabilitation. We consider concurrently the motivation of the user and his/her performance in a Pong game. User motivation is classified in three levels (not motivated, well motivated and overloaded). User performance is measured as a combination of knowledge of results--achieved goals and score points in the game--and knowledge of performance--joint displacement, speed, aiming, user work, etc. Initial results of a pilot test with unimpaired healthy young volunteers are also presented showing a tendency for individualization of the parameter values. PMID:22254578

  8. 76 FR 30193 - National Fish, Wildlife, and Plants Climate Adaptation Strategy; Notice of Intent: Request for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-24

    ... Fish and Wildlife Service National Fish, Wildlife, and Plants Climate Adaptation Strategy; Notice of... National Fish, Wildlife, and Plants Climate Adaptation Strategy (Strategy). The Strategy will provide a... impacts of climate change on fish, wildlife, plants, habitats, and our natural resource heritage. It...

  9. Control Reallocation Strategies for Damage Adaptation in Transport Class Aircraft

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen; Krishnakumar, K.; Limes, Greg; Bryant, Don

    2003-01-01

    This paper examines the feasibility, potential benefits and implementation issues associated with retrofitting a neural-adaptive flight control system (NFCS) to existing transport aircraft, including both cable/hydraulic and fly-by-wire configurations. NFCS uses a neural network based direct adaptive control approach for applying alternate sources of control authority in the presence of damage or failures in order to achieve desired flight control performance. Neural networks are used to provide consistent handling qualities across flight conditions, adapt to changes in aircraft dynamics and to make the controller easy to apply when implemented on different aircraft. Full-motion piloted simulation studies were performed on two different transport models: the Boeing 747-400 and the Boeing C-17. Subjects included NASA, Air Force and commercial airline pilots. Results demonstrate the potential for improving handing qualities and significantly increased survivability rates under various simulated failure conditions.

  10. Finite element/finite volume approaches with adaptive time stepping strategies for transient thermal problems

    NASA Technical Reports Server (NTRS)

    Mohan, Ram V.; Tamma, Kumar K.

    1993-01-01

    An adaptive time stepping strategy for transient thermal analysis of engineering systems is described which computes the time step based on the local truncation error with a good global error control and obtains optimal time steps to be used during the analysis. Combined mesh partitionings involving FEM/FVM meshes based on physical situations to obtain numerically improved physical representations are also proposed. Numerical test cases are described and comparative pros and cons are identified for practical situations.

  11. Assessing Climate Change Adaptation Strategies for Transportation Infrastructure

    NASA Astrophysics Data System (ADS)

    Armstrong, A.; Keller, J.; Meyer, M. D.; Flood, M.

    2011-12-01

    The transportation infrastructure, with long design life of 50 years and more, is susceptible to climate change. This paper describes an approach for assessing climate change adaptation strategies for transportation infrastructure, principally roadways and bridges. It is acknowledged that the affects and timing of climate changes are difficult to anticipate and that planning and design has its own inherent risks that must be considered on top of the uncertainty of climate change. Those conditions notwithstanding, climatologists, planners, and engineers are working on ways to reduce uncertainty and deal with risks in ways that can result in facilities that can provide reasonable levels of service, appropriate to their requirements in ways that are safe, efficient, and cost-effective. This paper first identifies the potential changes in climate and local environmental conditions and impacts that will be of interest to the transportation designer; then discusses the status of climate forecasting, one of the great uncertainties in climate adaptation planning; and finally addresses climate and design risk and suggests approaches to dealing with expected changes. The adaptation strategy must be responsive to future conditions that can be very different than those of the past. Therefore, the paper describes approaches that include allowing for flexibility in designs, developing alternative scenarios and responses, performing sensitivity analysis, incorporating risk assessment / management techniques integrated with climate forecasting and infrastructure design. By utilizing these approaches, transportation facilities can be designed so that they can be expected to meet their requirements without being over designed. Such an approach will also minimize the total life-cycle cost.

  12. Dosimetric evaluation of three adaptive strategies for prostate cancer treatment including pelvic lymph nodes irradiation

    SciTech Connect

    Cantin, Audrey; Gingras, Luc; Archambault, Louis; Lachance, Bernard; Foster, William; Goudreault, Julie

    2015-12-15

    Purpose: The movements of the prostate relative to the pelvic lymph nodes during intensity-modulated radiation therapy treatment can limit margin reduction and affect the protection of the organs at risk (OAR). In this study, the authors performed an analysis of three adaptive treatment strategies that combine information from both bony and gold marker registrations. The robustness of those treatments against the interfraction prostate movements was evaluated. Methods: A retrospective study was conducted on five prostate cancer patients with 7–13 daily cone-beam CTs (CBCTs). The clinical target volumes (CTVs) consisting of pelvic lymph nodes, prostate, and seminal vesicles as well as the OARs were delineated on each CBCT and the initial CT. Three adaptive strategies were analyzed. Two of these methods relied on a two-step patient positioning at each fraction. First step: a bony registration was used to deliver the nodal CTV prescription. Second step: a gold marker registration was then used either to (1) complete the dose delivered to the prostate (complement); (2) or give almost the entire prescription to the prostate with a weak dose gradient between the targets to compensate for possible motions (gradient). The third method (COR) used a pool of precalculated plans based on images acquired at previous treatment fractions. At each new fraction, a plan is selected from that pool based on the daily position of prostate center-of-mass. The dosimetric comparison was conducted and results are presented with and without the systematic shift in the prostate position on the CT planning. The adaptive strategies were compared to the current clinical standard where all fractions are treated with the initial nonadaptive plan. Results: The minimum daily prostate D{sub 95%} is improved by 2%, 9%, and 6% for the complement, the gradient, and the COR approaches, respectively, compared to the nonadaptive method. The average nodal CTV D{sub 95%} remains constant across the

  13. Alternative adaptive immunity strategies: coelacanth, cod and shark immunity.

    PubMed

    Buonocore, Francesco; Gerdol, Marco

    2016-01-01

    The advent of high throughput sequencing has permitted to investigate the genome and the transcriptome of novel non-model species with unprecedented depth. This technological advance provided a better understanding of the evolution of adaptive immune genes in gnathostomes, revealing several unexpected features in different fish species which are of particular interest. In the present paper, we review the current understanding of the adaptive immune system of the coelacanth, the elephant shark and the Atlantic cod. The study of coelacanth, the only living extant of the long thought to be extinct Sarcopterygian lineage, is fundamental to bring new insights on the evolution of the immune system in higher vertebrates. Surprisingly, coelacanths are the only known jawed vertebrates to lack IgM, whereas two IgD/W loci are present. Cartilaginous fish are of great interest due to their basal position in the vertebrate tree of life; the genome of the elephant shark revealed the lack of several important immune genes related to T cell functions, which suggest the existence of a primordial set of TH1-like cells. Finally, the Atlantic cod lacks a functional major histocompatibility II complex, but balances this evolutionary loss with the expansion of specific gene families, including MHC I, Toll-like receptors and antimicrobial peptides. Overall, these data point out that several fish species present an unconventional adaptive immune system, but the loss of important immune genes is balanced by adaptive evolutionary strategies which still guarantee the establishment of an efficient immune response against the pathogens they have to fight during their life.

  14. Adaptable state based control system

    NASA Technical Reports Server (NTRS)

    Rasmussen, Robert D. (Inventor); Dvorak, Daniel L. (Inventor); Gostelow, Kim P. (Inventor); Starbird, Thomas W. (Inventor); Gat, Erann (Inventor); Chien, Steve Ankuo (Inventor); Keller, Robert M. (Inventor)

    2004-01-01

    An autonomous controller, comprised of a state knowledge manager, a control executor, hardware proxies and a statistical estimator collaborates with a goal elaborator, with which it shares common models of the behavior of the system and the controller. The elaborator uses the common models to generate from temporally indeterminate sets of goals, executable goals to be executed by the controller. The controller may be updated to operate in a different system or environment than that for which it was originally designed by the replacement of shared statistical models and by the instantiation of a new set of state variable objects derived from a state variable class. The adaptation of the controller does not require substantial modification of the goal elaborator for its application to the new system or environment.

  15. Exercise-induced stress response as an adaptive tolerance strategy.

    PubMed Central

    Sonneborn, J S; Barbee, S A

    1998-01-01

    Interaction between the quality of the environment and the health of the exposed population determines the survival response of living organisms. The phenomenon of induced tolerance by exposure to threshold levels of stressors to stimulate natural defense mechanisms has potential therapeutic value. The paucity of information on predictability of individual response and information on the operative fundamental mechanisms limit applicability of the adaptive tolerance strategy. A potential biomarker of the stress response includes members of the stress-inducible ubiquitin gene family. Transcript sizes detected with Northern blot analysis identify different classes of ubiquitin gene family members and the intensity of the radioactive signal allows abundance determinations. Using moderate exercise as the stressor, significant increase (p < 0.028) in abundance of inducible polyubiquitin genes was found in human blood. Both the potential of exercise as a model system of a natural stress inducer and polyubiquitin as a biomarker of stress were established in these studies. Images Figure 1 Figure 2 PMID:9539026

  16. Global isotope metabolomics reveals adaptive strategies for nitrogen assimilation

    DOE PAGES

    Kurczy, Michael E.; Forsberg, Erica M.; Thorgersen, Michael P.; Poole, Farris L.; Benton, H. Paul; Ivanisevic, Julijana; Tran, Minerva L.; Wall, Judy D.; Elias, Dwayne A.; Adams, Michael W. W.; et al

    2016-04-05

    Nitrogen cycling is a microbial metabolic process essential for global ecological/agricultural balance. To investigate the link between the well-established ammonium and the alternative nitrate assimilation metabolic pathways, global isotope metabolomics was employed to examine three nitrate reducing bacteria using 15NO3 as a nitrogen source. In contrast to a control (Pseudomonas stutzeri RCH2), the results show that two of the isolates from Oak Ridge, Tennessee (Pseudomonas N2A2 and N2E2) utilize nitrate and ammonia for assimilation concurrently with differential labeling observed across multiple classes of metabolites including amino acids and nucleotides. The data reveal that the N2A2 and N2E2 strains conserve nitrogen-containingmore » metabolites, indicating that the nitrate assimilation pathway is a conservation mechanism for the assimilation of nitrogen. Co-utilization of nitrate and ammonia is likely an adaption to manage higher levels of nitrite since the denitrification pathways utilized by the N2A2 and N2E2 strains from the Oak Ridge site are predisposed to the accumulation of the toxic nitrite. In conclusion, the use of global isotope metabolomics allowed for this adaptive strategy to be investigated, which would otherwise not have been possible to decipher.« less

  17. Stress Response and Perinatal Reprogramming: Unraveling (Mal)adaptive Strategies

    PubMed Central

    Musazzi, Laura; Marrocco, Jordan

    2016-01-01

    Environmental stressors induce coping strategies in the majority of individuals. The stress response, involving the activation of the hypothalamic-pituitary-adrenocortical axis and the consequent release of corticosteroid hormones, is indeed aimed at promoting metabolic, functional, and behavioral adaptations. However, behavioral stress is also associated with fast and long-lasting neurochemical, structural, and behavioral changes, leading to long-term remodeling of glutamate transmission, and increased susceptibility to neuropsychiatric disorders. Of note, early-life events, both in utero and during the early postnatal life, trigger reprogramming of the stress response, which is often associated with loss of stress resilience and ensuing neurobehavioral (mal)adaptations. Indeed, adverse experiences in early life are known to induce long-term stress-related neuropsychiatric disorders in vulnerable individuals. Here, we discuss recent findings about stress remodeling of excitatory neurotransmission and brain morphology in animal models of behavioral stress. These changes are likely driven by epigenetic factors that lie at the core of the stress-response reprogramming in individuals with a history of perinatal stress. We propose that reprogramming mechanisms may underlie the reorganization of excitatory neurotransmission in the short- and long-term response to stressful stimuli. PMID:27057367

  18. 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.

  19. Adaptive governance and institutional strategies for climate-induced community relocations in Alaska.

    PubMed

    Bronen, Robin; Chapin, F Stuart

    2013-06-01

    This article presents governance and institutional strategies for climate-induced community relocations. In Alaska, repeated extreme weather events coupled with climate change-induced coastal erosion impact the habitability of entire communities. Community residents and government agencies concur that relocation is the only adaptation strategy that can protect lives and infrastructure. Community relocation stretches the financial and institutional capacity of existing governance institutions. Based on a comparative analysis of three Alaskan communities, Kivalina, Newtok, and Shishmaref, which have chosen to relocate, we examine the institutional constraints to relocation in the United States. We identify policy changes and components of a toolkit that can facilitate community-based adaptation when environmental events threaten people's lives and protection in place is not possible. Policy changes include amendment of the Stafford Act to include gradual geophysical processes, such as erosion, in the statutory definition of disaster and the creation of an adaptive governance framework to allow communities a continuum of responses from protection in place to community relocation. Key components of the toolkit are local leadership and integration of social and ecological well-being into adaptation planning.

  20. Adaptive governance and institutional strategies for climate-induced community relocations in Alaska

    PubMed Central

    Bronen, Robin; Chapin, F. Stuart

    2013-01-01

    This article presents governance and institutional strategies for climate-induced community relocations. In Alaska, repeated extreme weather events coupled with climate change-induced coastal erosion impact the habitability of entire communities. Community residents and government agencies concur that relocation is the only adaptation strategy that can protect lives and infrastructure. Community relocation stretches the financial and institutional capacity of existing governance institutions. Based on a comparative analysis of three Alaskan communities, Kivalina, Newtok, and Shishmaref, which have chosen to relocate, we examine the institutional constraints to relocation in the United States. We identify policy changes and components of a toolkit that can facilitate community-based adaptation when environmental events threaten people’s lives and protection in place is not possible. Policy changes include amendment of the Stafford Act to include gradual geophysical processes, such as erosion, in the statutory definition of disaster and the creation of an adaptive governance framework to allow communities a continuum of responses from protection in place to community relocation. Key components of the toolkit are local leadership and integration of social and ecological well-being into adaptation planning. PMID:23690592

  1. Adaptive governance and institutional strategies for climate-induced community relocations in Alaska.

    PubMed

    Bronen, Robin; Chapin, F Stuart

    2013-06-01

    This article presents governance and institutional strategies for climate-induced community relocations. In Alaska, repeated extreme weather events coupled with climate change-induced coastal erosion impact the habitability of entire communities. Community residents and government agencies concur that relocation is the only adaptation strategy that can protect lives and infrastructure. Community relocation stretches the financial and institutional capacity of existing governance institutions. Based on a comparative analysis of three Alaskan communities, Kivalina, Newtok, and Shishmaref, which have chosen to relocate, we examine the institutional constraints to relocation in the United States. We identify policy changes and components of a toolkit that can facilitate community-based adaptation when environmental events threaten people's lives and protection in place is not possible. Policy changes include amendment of the Stafford Act to include gradual geophysical processes, such as erosion, in the statutory definition of disaster and the creation of an adaptive governance framework to allow communities a continuum of responses from protection in place to community relocation. Key components of the toolkit are local leadership and integration of social and ecological well-being into adaptation planning. PMID:23690592

  2. Covariance Matrix Adaptation Evolutionary Strategy for Drift Correction of Electronic Nose Data

    NASA Astrophysics Data System (ADS)

    Di Carlo, S.; Falasconi, M.; Sanchez, E.; Sberveglieri, G.; Scionti, A.; Squillero, G.; Tonda, A.

    2011-09-01

    Electronic Noses (ENs) might represent a simple, fast, high sample throughput and economic alternative to conventional analytical instruments [1]. However, gas sensors drift still limits the EN adoption in real industrial setups due to high recalibration effort and cost [2]. In fact, pattern recognition (PaRC) models built in the training phase become useless after a period of time, in some cases a few weeks. Although algorithms to mitigate the drift date back to the early 90 this is still a challenging issue for the chemical sensor community [3]. Among other approaches, adaptive drift correction methods adjust the PaRC model in parallel with data acquisition without need of periodic calibration. Self-Organizing Maps (SOMs) [4] and Adaptive Resonance Theory (ART) networks [5] have been already tested in the past with fair success. This paper presents and discusses an original methodology based on a Covariance Matrix Adaptation Evolution Strategy (CMA-ES) [6], suited for stochastic optimization of complex problems.

  3. Delayed feedback during sensorimotor learning selectively disrupts adaptation but not strategy use.

    PubMed

    Brudner, Samuel N; Kethidi, Nikhit; Graeupner, Damaris; Ivry, Richard B; Taylor, Jordan A

    2016-03-01

    In sensorimotor adaptation tasks, feedback delays can cause significant reductions in the rate of learning. This constraint is puzzling given that many skilled behaviors have inherently long delays (e.g., hitting a golf ball). One difference in these task domains is that adaptation is primarily driven by error-based feedback, whereas skilled performance may also rely to a large extent on outcome-based feedback. This difference suggests that error- and outcome-based feedback may engage different learning processes, and these processes may be associated with different temporal constraints. We tested this hypothesis in a visuomotor adaptation task. Error feedback was indicated by the terminal position of a cursor, while outcome feedback was indicated by points. In separate groups of participants, the two feedback signals were presented immediately at the end of the movement, after a delay, or with just the error feedback delayed. Participants learned to counter the rotation in a similar manner regardless of feedback delay. However, the aftereffect, an indicator of implicit motor adaptation, was attenuated with delayed error feedback, consistent with the hypothesis that a different learning process supports performance under delay. We tested this by employing a task that dissociates the contribution of explicit strategies and implicit adaptation. We find that explicit aiming strategies contribute to the majority of the learning curve, regardless of delay; however, implicit learning, measured over the course of learning and by aftereffects, was significantly attenuated with delayed error-based feedback. These experiments offer new insight into the temporal constraints associated with different motor learning processes. PMID:26792878

  4. Using a mini-Raman spectrometer to monitor the adaptive strategies of extremophile colonizers in arid deserts: relationships between signal strength, adaptive strategies, solar radiation, and humidity.

    PubMed

    Miralles, I; Jorge-Villar, S E; Cantón, Y; Domingo, F

    2012-08-01

    The survival strategies of one cyanobacteria colony and three terricolous lichen species from the hot subdesert of Tabernas, Spain, were studied along with topographical attributes of the area to investigate whether the protective strategies adopted by these pioneer soil colonizers are related to the environmental stressors under which they survive. A handheld Raman spectrometer was used for biomolecular characterization, while the microclimatic and topographic parameters were estimated with a Geographic Information System (GIS). We found that the survival strategies adopted by those organisms are based on different combinations of protective biomolecules, each with diverse ecophysiological functions, such as UV-radiation screening, free-energy quenching, antioxidants, and the production of different types and amounts of calcium oxalates. Our results show that the cyanobacteria community and each lichen species preferentially colonized a particular microhabitat with specific moisture and incident solar radiation levels and exhibited different adaptive mechanisms. In recent years, a number of studies have provided consistent results that suggest a link between the strategies adopted by those extremophile organisms and the microclimatic environmental parameters. To date, however, far too little attention has been paid to results from Raman analyses on dry specimens. Therefore, the results of the present study, produced with the use of our miniaturized instrument, will be of interest to future studies in astrobiology, especially due to the likely use of Raman spectroscopy at the surface of Mars.

  5. Using a mini-Raman spectrometer to monitor the adaptive strategies of extremophile colonizers in arid deserts: relationships between signal strength, adaptive strategies, solar radiation, and humidity.

    PubMed

    Miralles, I; Jorge-Villar, S E; Cantón, Y; Domingo, F

    2012-08-01

    The survival strategies of one cyanobacteria colony and three terricolous lichen species from the hot subdesert of Tabernas, Spain, were studied along with topographical attributes of the area to investigate whether the protective strategies adopted by these pioneer soil colonizers are related to the environmental stressors under which they survive. A handheld Raman spectrometer was used for biomolecular characterization, while the microclimatic and topographic parameters were estimated with a Geographic Information System (GIS). We found that the survival strategies adopted by those organisms are based on different combinations of protective biomolecules, each with diverse ecophysiological functions, such as UV-radiation screening, free-energy quenching, antioxidants, and the production of different types and amounts of calcium oxalates. Our results show that the cyanobacteria community and each lichen species preferentially colonized a particular microhabitat with specific moisture and incident solar radiation levels and exhibited different adaptive mechanisms. In recent years, a number of studies have provided consistent results that suggest a link between the strategies adopted by those extremophile organisms and the microclimatic environmental parameters. To date, however, far too little attention has been paid to results from Raman analyses on dry specimens. Therefore, the results of the present study, produced with the use of our miniaturized instrument, will be of interest to future studies in astrobiology, especially due to the likely use of Raman spectroscopy at the surface of Mars. PMID:22970864

  6. Floral thermogenesis: An adaptive strategy of pollination biology in Magnoliaceae.

    PubMed

    Wang, Ruohan; Zhang, Zhixiang

    2015-01-01

    Floral thermogenesis plays a crucial role in pollination biology, especially in plant-pollinator interactions. We have recently explored how thermogenesis is related to pollinator activity and odour release in Magnolia sprengeri. By analyzing flower temperatures, emission of volatiles, and insect visitation, we found that floral blends released during pistillate and staminate stages were similar and coincided with sap beetle visitation. Thus, odour mimicry of staminate-stage flowers may occur during the pistillate stage and may be an adaptive strategy of Magnolia species to attract pollinators during both stages, ensuring successful pollination. In addition to the biological significance of floral thermogenesis in Magnolia species, we explored the underlying regulatory mechanisms via profiling miRNA expression in M. denudata flowers during thermogenic and non-thermogenic stages. We identified 17 miRNAs that may play regulatory roles in floral thermogenesis. Functional annotation of their target genes indicated that these miRNAs regulate floral thermogenesis by influencing cellular respiration and light reactions. These findings increase our understanding of plant-pollinator interactions and the regulatory mechanisms in thermogenic plants. PMID:26844867

  7. Floral thermogenesis: An adaptive strategy of pollination biology in Magnoliaceae

    PubMed Central

    Wang, Ruohan; Zhang, Zhixiang

    2015-01-01

    Floral thermogenesis plays a crucial role in pollination biology, especially in plant–pollinator interactions. We have recently explored how thermogenesis is related to pollinator activity and odour release in Magnolia sprengeri. By analyzing flower temperatures, emission of volatiles, and insect visitation, we found that floral blends released during pistillate and staminate stages were similar and coincided with sap beetle visitation. Thus, odour mimicry of staminate-stage flowers may occur during the pistillate stage and may be an adaptive strategy of Magnolia species to attract pollinators during both stages, ensuring successful pollination. In addition to the biological significance of floral thermogenesis in Magnolia species, we explored the underlying regulatory mechanisms via profiling miRNA expression in M. denudata flowers during thermogenic and non-thermogenic stages. We identified 17 miRNAs that may play regulatory roles in floral thermogenesis. Functional annotation of their target genes indicated that these miRNAs regulate floral thermogenesis by influencing cellular respiration and light reactions. These findings increase our understanding of plant–pollinator interactions and the regulatory mechanisms in thermogenic plants. PMID:26844867

  8. Floral thermogenesis: An adaptive strategy of pollination biology in Magnoliaceae.

    PubMed

    Wang, Ruohan; Zhang, Zhixiang

    2015-01-01

    Floral thermogenesis plays a crucial role in pollination biology, especially in plant-pollinator interactions. We have recently explored how thermogenesis is related to pollinator activity and odour release in Magnolia sprengeri. By analyzing flower temperatures, emission of volatiles, and insect visitation, we found that floral blends released during pistillate and staminate stages were similar and coincided with sap beetle visitation. Thus, odour mimicry of staminate-stage flowers may occur during the pistillate stage and may be an adaptive strategy of Magnolia species to attract pollinators during both stages, ensuring successful pollination. In addition to the biological significance of floral thermogenesis in Magnolia species, we explored the underlying regulatory mechanisms via profiling miRNA expression in M. denudata flowers during thermogenic and non-thermogenic stages. We identified 17 miRNAs that may play regulatory roles in floral thermogenesis. Functional annotation of their target genes indicated that these miRNAs regulate floral thermogenesis by influencing cellular respiration and light reactions. These findings increase our understanding of plant-pollinator interactions and the regulatory mechanisms in thermogenic plants.

  9. Fire risk and adaptation strategies in Northern Eurasian forests

    NASA Astrophysics Data System (ADS)

    Shvidenko, Anatoly; Schepaschenko, Dmitry

    2013-04-01

    permafrost areas. Overall, Russia should expect a disproportionate escalation of fire regimes compared to increasing climatic fire danger. Thus, development and implementation of an efficient adaptation strategy is a pressing problem of current forest management of the country. An appropriate system of forest fire protection which would be able to meet challenges of future climates is a corner stone of such a strategy. We consider possible systems solutions of this complex problem including (1) integrated ecological and socio-economic analysis of current and future fire regimes; (2) regional requirements to and specific features of a new paradigm of forest fire protection in the boreal zone of Northern Eurasia; (3) anticipatory strategy of the prevention of large-scale disturbances in forests, including adaptation of forest landscapes to the future climates (regulation of tree composition; setup of relevant spatial structure of forest landscapes; etc.); (4) implementation of an effective system of forest monitoring as part of integrated observing systems; (5) transition to ecologically-friendly systems of industrial development of northern territories; (6) development of new/ improvement of existing legislation and institutional frameworks of forest management which would be satisfactory to react on challenges of climate change; and (6) international cooperation.

  10. Livestock in a changing climate: production system transitions as an adaptation strategy for agriculture

    NASA Astrophysics Data System (ADS)

    Weindl, Isabelle; Lotze-Campen, Hermann; Popp, Alexander; Müller, Christoph; Havlík, Petr; Herrero, Mario; Schmitz, Christoph; Rolinski, Susanne

    2015-09-01

    Livestock farming is the world’s largest land use sector and utilizes around 60% of the global biomass harvest. Over the coming decades, climate change will affect the natural resource base of livestock production, especially the productivity of rangeland and feed crops. Based on a comprehensive impact modeling chain, we assess implications of different climate projections for agricultural production costs and land use change and explore the effectiveness of livestock system transitions as an adaptation strategy. Simulated climate impacts on crop yields and rangeland productivity generate adaptation costs amounting to 3% of total agricultural production costs in 2045 (i.e. 145 billion US). Shifts in livestock production towards mixed crop-livestock systems represent a resource- and cost-efficient adaptation option, reducing agricultural adaptation costs to 0.3% of total production costs and simultaneously abating deforestation by about 76 million ha globally. The relatively positive climate impacts on grass yields compared with crop yields favor grazing systems inter alia in South Asia and North America. Incomplete transitions in production systems already have a strong adaptive and cost reducing effect: a 50% shift to mixed systems lowers agricultural adaptation costs to 0.8%. General responses of production costs to system transitions are robust across different global climate and crop models as well as regarding assumptions on CO2 fertilization, but simulated values show a large variation. In the face of these uncertainties, public policy support for transforming livestock production systems provides an important lever to improve agricultural resource management and lower adaptation costs, possibly even contributing to emission reduction.

  11. Adaptive and qualitative changes in encoding strategy with experience: evidence from the test-expectancy paradigm.

    PubMed

    Finley, Jason R; Benjamin, Aaron S

    2012-05-01

    Three experiments demonstrated learners' abilities to adaptively and qualitatively accommodate their encoding strategies to the demands of an upcoming test. Stimuli were word pairs. In Experiment 1, test expectancy was induced for either cued recall (of targets given cues) or free recall (of targets only) across 4 study-test cycles of the same test format, followed by a final critical cycle featuring either the expected or the unexpected test format. For final tests of both cued and free recall, participants who had expected that test format outperformed those who had not. This disordinal interaction, supported by recognition and self-report data, demonstrated not mere differences in effort based on anticipated test difficulty, but rather qualitative and appropriate differences in encoding strategies based on expected task demands. Participants also came to appropriately modulate metacognitive monitoring (Experiment 2) and study-time allocation (Experiment 3) across study-test cycles. Item and associative recognition performance, as well as self-report data, revealed shifts in encoding strategies across trials; these results were used to characterize and evaluate the different strategies that participants employed for cued versus free recall and to assess the optimality of participants' metacognitive control of encoding strategies. Taken together, these data illustrate a sophisticated form of metacognitive control, in which learners qualitatively shift encoding strategies to match the demands of anticipated tests. PMID:22103783

  12. Adaptive and Qualitative Changes in Encoding Strategy With Experience: Evidence From the Test-Expectancy Paradigm

    PubMed Central

    Finley, Jason R.; Benjamin, Aaron S.

    2012-01-01

    Three experiments demonstrated learners’ abilities to adaptively and qualitatively accommodate their encoding strategies to the demands of an upcoming test. Stimuli were word pairs. In Experiment 1, test expectancy was induced for either cued recall (of targets given cues) or free recall (of targets only) across 4 study–test cycles of the same test format, followed by a final critical cycle featuring either the expected or the unexpected test format. For final tests of both cued and free recall, participants who had expected that test format outperformed those who had not. This disordinal interaction, supported by recognition and self-report data, demonstrated not mere differences in effort based on anticipated test difficulty, but rather qualitative and appropriate differences in encoding strategies based on expected task demands. Participants also came to appropriately modulate metacognitive monitoring (Experiment 2) and study-time allocation (Experiment 3) across study–test cycles. Item and associative recognition performance, as well as self-report data, revealed shifts in encoding strategies across trials; these results were used to characterize and evaluate the different strategies that participants employed for cued versus free recall and to assess the optimality of participants’ metacognitive control of encoding strategies. Taken together, these data illustrate a sophisticated form of metacognitive control, in which learners qualitatively shift encoding strategies to match the demands of anticipated tests. PMID:22103783

  13. QPSO-based adaptive DNA computing algorithm.

    PubMed

    Karakose, Mehmet; Cigdem, Ugur

    2013-01-01

    DNA (deoxyribonucleic acid) computing that is a new computation model based on DNA molecules for information storage has been increasingly used for optimization and data analysis in recent years. However, DNA computing algorithm has some limitations in terms of convergence speed, adaptability, and effectiveness. In this paper, a new approach for improvement of DNA computing is proposed. This new approach aims to perform DNA computing algorithm with adaptive parameters towards the desired goal using quantum-behaved particle swarm optimization (QPSO). Some contributions provided by the proposed QPSO based on adaptive DNA computing algorithm are as follows: (1) parameters of population size, crossover rate, maximum number of operations, enzyme and virus mutation rate, and fitness function of DNA computing algorithm are simultaneously tuned for adaptive process, (2) adaptive algorithm is performed using QPSO algorithm for goal-driven progress, faster operation, and flexibility in data, and (3) numerical realization of DNA computing algorithm with proposed approach is implemented in system identification. Two experiments with different systems were carried out to evaluate the performance of the proposed approach with comparative results. Experimental results obtained with Matlab and FPGA demonstrate ability to provide effective optimization, considerable convergence speed, and high accuracy according to DNA computing algorithm.

  14. [Germination strategy and ecological adaptability of Eragrostis pilosa].

    PubMed

    Li, Xuehua; Li, Xiaola; Jiang, Deming; Liu, Zhimin

    2006-04-01

    The study on the germination strategy of Eragrostis pilosa under different storage and environmental conditions showed that freshly collected E. pilosa seeds had a stronger innate dormancy. Chilling and dry storage for 4 months had no obvious effect on releasing from dormancy, while longer time storage could facilitate seed maturation. The seeds could germinate either in light or in darkness, and stronger light was in favor of germination. The optimal temperature for germination was 28 degrees C, while higher or lower temperature could result in the decrease of germination. The germination percentage of seeds under changed temperature (16 to 28 degrees C) was higher than that under constant temperature (28 degrees C), but with no significant difference. The critical amount of rain for seed germination was about 10 mm, and the germination percentage and duration all increased with increasing rainfall. E. pilosa had two germination strategies, i. e., quick germination and dormancy for more than one year. Based on the seed morphological characters and germination strategies, it could be concluded that E. pilosa had a persistent soil seed bank.

  15. Adaptive Strategies, Gender Ideology, and Work-Family Balance among Dutch Dual Earners

    ERIC Educational Resources Information Center

    Wierda-Boer, Hilde H.; Gerris, Jan R. M.; Vermulst, Ad A.

    2008-01-01

    Using questionnaire data on 149 Dutch dual-earner couples with young children participating in the European Famwork study, we examine how adaptive strategies and gender ideology relate to parents' perceived success in balancing work and family. Path analysis indicates that some adaptive strategies may harm individuals' work-family balance,…

  16. Urban plant physiology: adaptation-mitigation strategies under permanent stress.

    PubMed

    Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

    2015-02-01

    Urban environments that are stressful for plant function and growth will become increasingly widespread in future. In this opinion article, we define the concept of 'urban plant physiology', which focuses on plant responses and long term adaptations to urban conditions and on the capacity of urban vegetation to mitigate environmental hazards in urbanized settings such as air and soil pollution. Use of appropriate control treatments would allow for studies in urban environments to be comparable to expensive manipulative experiments. In this opinion article, we propose to couple two approaches, based either on environmental gradients or manipulated gradients, to develop the concept of urban plant physiology for assessing how single or multiple environmental factors affect the key environmental services provided by urban forests.

  17. Adaptation Strategies of Individuals With Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Roper, Jaimie A.; Terza, Matthew J.; Tillman, Mark D.; Hass, Chris J.

    2016-01-01

    Background: Despite the strong implications for rehabilitation design, the capability of individuals with anterior cruciate ligament reconstruction (ACLR) to adapt and store novel gait patterns have not been well studied. Purpose: To investigate how reconstructive surgery may affect the ability to adapt and store novel gait patterns in persons with ACLR while walking on a split-belt treadmill. Study Design: Controlled laboratory study. Methods: Gait adaptation was compared between 20 participants with ACLR and 20 healthy controls during split-belt treadmill walking. Gait adaptation was assessed in slow- and fast-adapting parameters by (1) the magnitude of symmetry during late adaptation and (2) the amount of the asymmetry during de-adaptation. Results: Healthy individuals adapted a new walking pattern and stored the new walking pattern equally in both the dominant and nondominant limbs. Conversely, individuals with ACLR displayed impairments in both slow-adapting and fast-adapting derived gait adaptation and significant differences in behavior between the reconstructed and uninjured limb. Conclusion: While surgical reconstruction and physical therapy are aimed at improving mechanical stability to the knee, the study data suggest that fundamental features of motor control remain altered. After ACLR, participants display an altered ability to learn and store functional gait patterns. PMID:26894200

  18. An adaptation strategy of using LDA classifier for EMG pattern recognition.

    PubMed

    Zhang, Haoshi; Zhao, Yaonan; Yao, Fuan; Xu, Lisheng; Shang, Peng; Li, Guanglin

    2013-01-01

    The time-varying character of myoelectric signal usually causes a low classification accuracy in traditional supervised pattern recognition method. In this work, an unsupervised adaptation strategy of linear discriminant analysis (ALDA) based on probability weighting and cycle substitution was suggested in order to improve the performance of electromyography (EMG)-based motion classification in multifunctional myoelectric prostheses control in changing environment. The adaptation procedure was firstly introduced, and then the proposed ALDA classifier was trained and tested with surface EMG recordings related to multiple motion patterns. The accuracies of the ALDA classifier and traditional LDA classifier were compared when the EMG recordings were added with different degrees of noise. The experimental results showed that compared to the LDA method, the suggested ALDA method had a better performance in improving the classification accuracy of sEMG pattern recognition, in both stable situation and noise added situation.

  19. Adaptive GOP structure based on motion coherence

    NASA Astrophysics Data System (ADS)

    Ma, Yanzhuo; Wan, Shuai; Chang, Yilin; Yang, Fuzheng; Wang, Xiaoyu

    2009-08-01

    Adaptive Group of Pictures (GOP) is helpful for increasing the efficiency of video encoding by taking account of characteristics of video content. This paper proposes a method for adaptive GOP structure selection for video encoding based on motion coherence, which extracts key frames according to motion acceleration, and assigns coding type for each key and non-key frame correspondingly. Motion deviation is then used instead of motion magnitude in the selection of the number of B frames. Experimental results show that the proposed method for adaptive GOP structure selection achieves performance gain of 0.2-1dB over the fixed GOP, and has the advantage of better transmission resilience. Moreover, this method can be used in real-time video coding due to its low complexity.

  20. Matched filter based iterative adaptive approach

    NASA Astrophysics Data System (ADS)

    Nepal, Ramesh; Zhang, Yan Rockee; Li, Zhengzheng; Blake, William

    2016-05-01

    Matched Filter sidelobes from diversified LPI waveform design and sensor resolution are two important considerations in radars and active sensors in general. Matched Filter sidelobes can potentially mask weaker targets, and low sensor resolution not only causes a high margin of error but also limits sensing in target-rich environment/ sector. The improvement in those factors, in part, concern with the transmitted waveform and consequently pulse compression techniques. An adaptive pulse compression algorithm is hence desired that can mitigate the aforementioned limitations. A new Matched Filter based Iterative Adaptive Approach, MF-IAA, as an extension to traditional Iterative Adaptive Approach, IAA, has been developed. MF-IAA takes its input as the Matched Filter output. The motivation here is to facilitate implementation of Iterative Adaptive Approach without disrupting the processing chain of traditional Matched Filter. Similar to IAA, MF-IAA is a user parameter free, iterative, weighted least square based spectral identification algorithm. This work focuses on the implementation of MF-IAA. The feasibility of MF-IAA is studied using a realistic airborne radar simulator as well as actual measured airborne radar data. The performance of MF-IAA is measured with different test waveforms, and different Signal-to-Noise (SNR) levels. In addition, Range-Doppler super-resolution using MF-IAA is investigated. Sidelobe reduction as well as super-resolution enhancement is validated. The robustness of MF-IAA with respect to different LPI waveforms and SNR levels is also demonstrated.

  1. The New Weather Radar for America's Space Program in Florida: A Temperature Profile Adaptive Scan Strategy

    NASA Technical Reports Server (NTRS)

    Carey, L. D.; Petersen, W. A.; Deierling, W.; Roeder, W. P.

    2009-01-01

    when geo-locating the radar beam (i.e., beam height and arc distance), including non-standard refraction based on the user-input temperature profile. In addition to temperature profile adaptivity, this paper will also summarize the other requirements for this scan strategy program such as detection of low-level boundaries, detection of anvil clouds, reducing the Cone Of Silence, and allowing for times when deep convective clouds will not occur. The adaptive technique will be carefully compared to and benchmarked against the new fixed scan strategy. Specific environmental scenarios in which the adaptive scan strategy is able to optimize and improve coverage and resolution at critical heights, scan time, and/or sample numbers relative to the fixed scan strategy will be presented.

  2. An adaptive regularization parameter choice strategy for multispectral bioluminescence tomography

    SciTech Connect

    Feng Jinchao; Qin Chenghu; Jia Kebin; Han Dong; Liu Kai; Zhu Shouping; Yang Xin; Tian Jie

    2011-11-15

    Purpose: Bioluminescence tomography (BLT) provides an effective tool for monitoring physiological and pathological activities in vivo. However, the measured data in bioluminescence imaging are corrupted by noise. Therefore, regularization methods are commonly used to find a regularized solution. Nevertheless, for the quality of the reconstructed bioluminescent source obtained by regularization methods, the choice of the regularization parameters is crucial. To date, the selection of regularization parameters remains challenging. With regards to the above problems, the authors proposed a BLT reconstruction algorithm with an adaptive parameter choice rule. Methods: The proposed reconstruction algorithm uses a diffusion equation for modeling the bioluminescent photon transport. The diffusion equation is solved with a finite element method. Computed tomography (CT) images provide anatomical information regarding the geometry of the small animal and its internal organs. To reduce the ill-posedness of BLT, spectral information and the optimal permissible source region are employed. Then, the relationship between the unknown source distribution and multiview and multispectral boundary measurements is established based on the finite element method and the optimal permissible source region. Since the measured data are noisy, the BLT reconstruction is formulated as l{sub 2} data fidelity and a general regularization term. When choosing the regularization parameters for BLT, an efficient model function approach is proposed, which does not require knowledge of the noise level. This approach only requests the computation of the residual and regularized solution norm. With this knowledge, we construct the model function to approximate the objective function, and the regularization parameter is updated iteratively. Results: First, the micro-CT based mouse phantom was used for simulation verification. Simulation experiments were used to illustrate why multispectral data were used

  3. Searching for adaptive traits in genetic resources - phenology based approach

    NASA Astrophysics Data System (ADS)

    Bari, Abdallah

    2015-04-01

    Searching for adaptive traits in genetic resources - phenology based approach Abdallah Bari, Kenneth Street, Eddy De Pauw, Jalal Eddin Omari, and Chandra M. Biradar International Center for Agricultural Research in the Dry Areas, Rabat Institutes, Rabat, Morocco Phenology is an important plant trait not only for assessing and forecasting food production but also for searching in genebanks for adaptive traits. Among the phenological parameters we have been considering to search for such adaptive and rare traits are the onset (sowing period) and the seasonality (growing period). Currently an application is being developed as part of the focused identification of germplasm strategy (FIGS) approach to use climatic data in order to identify crop growing seasons and characterize them in terms of onset and duration. These approximations of growing period characteristics can then be used to estimate flowering and maturity dates for dryland crops, such as wheat, barley, faba bean, lentils and chickpea, and assess, among others, phenology-related traits such as days to heading [dhe] and grain filling period [gfp]. The approach followed here is based on first calculating long term average daily temperatures by fitting a curve to the monthly data over days from beginning of the year. Prior to the identification of these phenological stages the onset is extracted first from onset integer raster GIS layers developed based on a model of the growing period that considers both moisture and temperature limitations. The paper presents some examples of real applications of the approach to search for rare and adaptive traits.

  4. Ethnic Visibility and Adaptive Strategies: Samoans in the Seattle Area

    ERIC Educational Resources Information Center

    Kotchek, Lydia

    1977-01-01

    Describes the ways and means of adaptation and interaction used by a purportedly invisible ethnic minority, the Samoan population of Seattle, Washington, and discusses both how these ways and means of adaptation and interaction relate to each other and how they are facilitated or blocked by the relative invisibility of the group. (Author/JM)

  5. Management Strategies for Complex Adaptive Systems: Sensemaking, Learning, and Improvisation

    ERIC Educational Resources Information Center

    McDaniel, Reuben R., Jr.

    2007-01-01

    Misspecification of the nature of organizations may be a major reason for difficulty in achieving performance improvement. Organizations are often viewed as machine-like, but complexity science suggests that organizations should be viewed as complex adaptive systems. I identify the characteristics of complex adaptive systems and give examples of…

  6. A belief-based evolutionarily stable strategy.

    PubMed

    Deng, Xinyang; Wang, Zhen; Liu, Qi; Deng, Yong; Mahadevan, Sankaran

    2014-11-21

    As an equilibrium refinement of the Nash equilibrium, evolutionarily stable strategy (ESS) is a key concept in evolutionary game theory and has attracted growing interest. An ESS can be either a pure strategy or a mixed strategy. Even though the randomness is allowed in mixed strategy, the selection probability of pure strategy in a mixed strategy may fluctuate due to the impact of many factors. The fluctuation can lead to more uncertainty. In this paper, such uncertainty involved in mixed strategy has been further taken into consideration: a belief strategy is proposed in terms of Dempster-Shafer evidence theory. Furthermore, based on the proposed belief strategy, a belief-based ESS has been developed. The belief strategy and belief-based ESS can reduce to the mixed strategy and mixed ESS, which provide more realistic and powerful tools to describe interactions among agents.

  7. Leaf Area Adjustment As an Optimal Drought-Adaptation Strategy

    NASA Astrophysics Data System (ADS)

    Manzoni, S.; Beyer, F.; Thompson, S. E.; Vico, G.; Weih, M.

    2014-12-01

    Leaf phenology plays a major role in land-atmosphere mass and energy exchanges. Much work has focused on phenological responses to light and temperature, but less to leaf area changes during dry periods. Because the duration of droughts is expected to increase under future climates in seasonally-dry as well as mesic environments, it is crucial to (i) predict drought-related phenological changes and (ii) to develop physiologically-sound models of leaf area dynamics during dry periods. Several optimization criteria have been proposed to model leaf area adjustment as soil moisture decreases. Some theories are based on the plant carbon (C) balance, hypothesizing that leaf area will decline when instantaneous net photosynthetic rates become negative (equivalent to maximization of cumulative C gain). Other theories draw on hydraulic principles, suggesting that leaf area should adjust to either maintain a constant leaf water potential (isohydric behavior) or to avoid leaf water potentials with negative impacts on photosynthesis (i.e., minimization of water stress). Evergreen leaf phenology is considered as a control case. Merging these theories into a unified framework, we quantify the effect of phenological strategy and climate forcing on the net C gain over the entire growing season. By accounting for the C costs of leaf flushing and the gains stemming from leaf photosynthesis, this metric assesses the effectiveness of different phenological strategies, under different climatic scenarios. Evergreen species are favored only when the dry period is relatively short, as they can exploit most of the growing season, and only incur leaf maintenance costs during the short dry period. In contrast, deciduous species that lower maintenance costs by losing leaves are advantaged under drier climates. Moreover, among drought-deciduous species, isohydric behavior leads to lowest C gains. Losing leaves gradually so as to maintain a net C uptake equal to zero during the driest period in

  8. The conflict adaptation is affected by attentional strategies: evidence from the arrow flanker task.

    PubMed

    Chen, Jia; Li, Chang; He, ChunHong; Chen, AnTao

    2009-10-01

    Recently, several studies have considered factors affecting the occurrence of congruency sequence effect (CSE) in the arrow flanker task. In the present study, the influence of the following factors was examined: the presentation of a fixation and the intertrial interval (ITI) were considered. Results of the study showed that the CSE was significant when there was no fixation and when the ITI was long for response repetitions and response changes, but disappeared for response change trials in other conditions. These results showed that, even in the arrow flanker task, the conflict adaptation effect did contribute to the CSE. The current results suggested that the conflict adaptation effect in the arrow flanker task was based on the appropriate application of attention strategies.

  9. Adaptive Work Strategy for Evaluating a Conceptual Site Model

    NASA Astrophysics Data System (ADS)

    Dietrich, P.; Utom, A. U.; Werban, U.

    2015-12-01

    A comprehensive, diagnostic, procedural and adaptive scheme involving a combination of geophysical and direct push methods was developed and applied in the Wurmlingen study site situated within the region of Baden-Württemberg (southwest Germany). The goal of the study was to test the applicability of electrical resistivity method in imaging resistivity contrasts, and mapping the depth to and lateral extent of field-scale subsurface structures and existence of flow paths that may control concentration gradients of groundwater solution contents. Based on a relatively fast and cost-effective areal mapping with vertical electrical sounding technique, a northwest-southeast trending stream-channel-like depression (low apparent resistivity feature) through a Pleistocene aquifer was detected. For a more detailed characterization, we implemented electrical resistivity tomography method followed by direct push (DP) technologies. Beside the use of DP for verification of structures identified by geophysical tools, we used it for multi-level groundwater sampling. Results from groundwater chemistry indicate zones of steep nitrate concentration gradients associated with the feature.

  10. Adaptive Cognitive-Based Selection of Learning Objects

    ERIC Educational Resources Information Center

    Karampiperis, Pythagoras; Lin, Taiyu; Sampson, Demetrios G.; Kinshuk

    2006-01-01

    Adaptive cognitive-based selection is recognized as among the most significant open issues in adaptive web-based learning systems. In order to adaptively select learning resources, the definition of adaptation rules according to the cognitive style or learning preferences of the learners is required. Although some efforts have been reported in…

  11. Remote sensing image subpixel mapping based on adaptive differential evolution.

    PubMed

    Zhong, Yanfei; Zhang, Liangpei

    2012-10-01

    In this paper, a novel subpixel mapping algorithm based on an adaptive differential evolution (DE) algorithm, namely, adaptive-DE subpixel mapping (ADESM), is developed to perform the subpixel mapping task for remote sensing images. Subpixel mapping may provide a fine-resolution map of class labels from coarser spectral unmixing fraction images, with the assumption of spatial dependence. In ADESM, to utilize DE, the subpixel mapping problem is transformed into an optimization problem by maximizing the spatial dependence index. The traditional DE algorithm is an efficient and powerful population-based stochastic global optimizer in continuous optimization problems, but it cannot be applied to the subpixel mapping problem in a discrete search space. In addition, it is not an easy task to properly set control parameters in DE. To avoid these problems, this paper utilizes an adaptive strategy without user-defined parameters, and a reversible-conversion strategy between continuous space and discrete space, to improve the classical DE algorithm. During the process of evolution, they are further improved by enhanced evolution operators, e.g., mutation, crossover, repair, exchange, insertion, and an effective local search to generate new candidate solutions. Experimental results using different types of remote images show that the ADESM algorithm consistently outperforms the previous subpixel mapping algorithms in all the experiments. Based on sensitivity analysis, ADESM, with its self-adaptive control parameter setting, is better than, or at least comparable to, the standard DE algorithm, when considering the accuracy of subpixel mapping, and hence provides an effective new approach to subpixel mapping for remote sensing imagery.

  12. Adaptive color correction based on object color classification

    NASA Astrophysics Data System (ADS)

    Kotera, Hiroaki; Morimoto, Tetsuro; Yasue, Nobuyuki; Saito, Ryoichi

    1998-09-01

    An adaptive color management strategy depending on the image contents is proposed. Pictorial color image is classified into different object areas with clustered color distribution. Euclidian or Mahalanobis color distance measures, and maximum likelihood method based on Bayesian decision rule, are introduced to the classification. After the classification process, each clustered pixels are projected onto principal component space by Hotelling transform and the color corrections are performed for the principal components to be matched each other in between the individual clustered color areas of original and printed images.

  13. An integrated framework for assessing vulnerability to climate change and developing adaptation strategies for coffee growing families in Mesoamerica.

    PubMed

    Baca, María; Läderach, Peter; Haggar, Jeremy; Schroth, Götz; Ovalle, Oriana

    2014-01-01

    The Mesoamerican region is considered to be one of the areas in the world most vulnerable to climate change. We developed a framework for quantifying the vulnerability of the livelihoods of coffee growers in Mesoamerica at regional and local levels and identify adaptation strategies. Following the Intergovernmental Panel on Climate Change (IPCC) concepts, vulnerability was defined as the combination of exposure, sensitivity and adaptive capacity. To quantify exposure, changes in the climatic suitability for coffee and other crops were predicted through niche modelling based on historical climate data and locations of coffee growing areas from Mexico, Guatemala, El Salvador and Nicaragua. Future climate projections were generated from 19 Global Circulation Models. Focus groups were used to identify nine indicators of sensitivity and eleven indicators of adaptive capacity, which were evaluated through semi-structured interviews with 558 coffee producers. Exposure, sensitivity and adaptive capacity were then condensed into an index of vulnerability, and adaptation strategies were identified in participatory workshops. Models predict that all target countries will experience a decrease in climatic suitability for growing Arabica coffee, with highest suitability loss for El Salvador and lowest loss for Mexico. High vulnerability resulted from loss in climatic suitability for coffee production and high sensitivity through variability of yields and out-migration of the work force. This was combined with low adaptation capacity as evidenced by poor post harvest infrastructure and in some cases poor access to credit and low levels of social organization. Nevertheless, the specific contributors to vulnerability varied strongly among countries, municipalities and families making general trends difficult to identify. Flexible strategies for adaption are therefore needed. Families need the support of government and institutions specialized in impacts of climate change and

  14. An Integrated Framework for Assessing Vulnerability to Climate Change and Developing Adaptation Strategies for Coffee Growing Families in Mesoamerica

    PubMed Central

    Baca, María; Läderach, Peter; Haggar, Jeremy; Schroth, Götz; Ovalle, Oriana

    2014-01-01

    The Mesoamerican region is considered to be one of the areas in the world most vulnerable to climate change. We developed a framework for quantifying the vulnerability of the livelihoods of coffee growers in Mesoamerica at regional and local levels and identify adaptation strategies. Following the Intergovernmental Panel on Climate Change (IPCC) concepts, vulnerability was defined as the combination of exposure, sensitivity and adaptive capacity. To quantify exposure, changes in the climatic suitability for coffee and other crops were predicted through niche modelling based on historical climate data and locations of coffee growing areas from Mexico, Guatemala, El Salvador and Nicaragua. Future climate projections were generated from 19 Global Circulation Models. Focus groups were used to identify nine indicators of sensitivity and eleven indicators of adaptive capacity, which were evaluated through semi-structured interviews with 558 coffee producers. Exposure, sensitivity and adaptive capacity were then condensed into an index of vulnerability, and adaptation strategies were identified in participatory workshops. Models predict that all target countries will experience a decrease in climatic suitability for growing Arabica coffee, with highest suitability loss for El Salvador and lowest loss for Mexico. High vulnerability resulted from loss in climatic suitability for coffee production and high sensitivity through variability of yields and out-migration of the work force. This was combined with low adaptation capacity as evidenced by poor post harvest infrastructure and in some cases poor access to credit and low levels of social organization. Nevertheless, the specific contributors to vulnerability varied strongly among countries, municipalities and families making general trends difficult to identify. Flexible strategies for adaption are therefore needed. Families need the support of government and institutions specialized in impacts of climate change and

  15. An integrated framework for assessing vulnerability to climate change and developing adaptation strategies for coffee growing families in Mesoamerica.

    PubMed

    Baca, María; Läderach, Peter; Haggar, Jeremy; Schroth, Götz; Ovalle, Oriana

    2014-01-01

    The Mesoamerican region is considered to be one of the areas in the world most vulnerable to climate change. We developed a framework for quantifying the vulnerability of the livelihoods of coffee growers in Mesoamerica at regional and local levels and identify adaptation strategies. Following the Intergovernmental Panel on Climate Change (IPCC) concepts, vulnerability was defined as the combination of exposure, sensitivity and adaptive capacity. To quantify exposure, changes in the climatic suitability for coffee and other crops were predicted through niche modelling based on historical climate data and locations of coffee growing areas from Mexico, Guatemala, El Salvador and Nicaragua. Future climate projections were generated from 19 Global Circulation Models. Focus groups were used to identify nine indicators of sensitivity and eleven indicators of adaptive capacity, which were evaluated through semi-structured interviews with 558 coffee producers. Exposure, sensitivity and adaptive capacity were then condensed into an index of vulnerability, and adaptation strategies were identified in participatory workshops. Models predict that all target countries will experience a decrease in climatic suitability for growing Arabica coffee, with highest suitability loss for El Salvador and lowest loss for Mexico. High vulnerability resulted from loss in climatic suitability for coffee production and high sensitivity through variability of yields and out-migration of the work force. This was combined with low adaptation capacity as evidenced by poor post harvest infrastructure and in some cases poor access to credit and low levels of social organization. Nevertheless, the specific contributors to vulnerability varied strongly among countries, municipalities and families making general trends difficult to identify. Flexible strategies for adaption are therefore needed. Families need the support of government and institutions specialized in impacts of climate change and

  16. Prostate Intrafraction Motion Assessed by Simultaneous kV Fluoroscopy at MV Delivery II: Adaptive Strategies

    SciTech Connect

    Adamson, Justus; Wu Qiuwen

    2010-12-01

    Purpose: To investigate potential benefits of adaptive strategies for managing prostate intrafractional uncertainties when interfraction motion is corrected online. Methods and Materials: Prostate intrafraction motion was measured using kV fluoroscopy during MV delivery for 571 fractions from 30 hypofractionated radiotherapy patients. We evaluated trending over treatment course using analysis of variance statistics, and we evaluated the ability to correct patient-specific systematic error and apply patient-specific statistical margins after 2 to 15 fractions to compensate 90% of motion. We also evaluated the ability to classify patients into small- and large-motion subgroups based on the first 2 to 20 fractions using discriminant analysis. Results: No time trend was observed over treatment course, and intrafraction motion was patient specific (p < 0.0001). Systematic error in the first week correlated well with that in subsequent weeks, with correlation coefficients of 0.53, 0.50, and 0.41 in right-left (RL), anterior-posterior (AP), and superior-inferior (SI), respectively. After 5 fractions, the adaptive strategy resulted in average margin reductions of 0.3, 0.7, and 0.7 mm in RL, AP, and SI, respectively, with margins ranging from 1 to 3.2 mm in RL, 2 to 7.0 mm in AP, and 2 to 6.6 mm in SI. By contrast, population margins to include the same percentage of motion were 1.7, 4.0, and 4.1 mm. After 2 and 5 fractions, patients were classified into small- and large-motion groups with {approx}77% and {approx}83% accuracy. Conclusions: Adaptive strategies are feasible and beneficial for intrafraction motion management in prostate cancer online image guidance. Patients may be classified into large- and small-motion groups in early fractions using discriminant analysis.

  17. When Easy Comes Hard: The Development of Adaptive Strategy Selection

    ERIC Educational Resources Information Center

    Mata, Rui; von Helversen, Bettina; Rieskamp, Jorg

    2011-01-01

    Can children learn to select the right strategy for a given problem? In one experiment, 9- to 10-year-olds (N = 50), 11- to 12-year-olds (N = 50), and adults (N = 50) made probabilistic inferences. Participants encountered environments favoring either an information-intensive strategy that integrates all available information or an…

  18. A hybrid strategy of offline adaptive planning and online image guidance for prostate cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Lei, Yu; Wu, Qiuwen

    2010-04-01

    Offline adaptive radiotherapy (ART) has been used to effectively correct and compensate for prostate motion and reduce the required margin. The efficacy depends on the characteristics of the patient setup error and interfraction motion through the whole treatment; specifically, systematic errors are corrected and random errors are compensated for through the margins. In online image-guided radiation therapy (IGRT) of prostate cancer, the translational setup error and inter-fractional prostate motion are corrected through pre-treatment imaging and couch correction at each fraction. However, the rotation and deformation of the target are not corrected and only accounted for with margins in treatment planning. The purpose of this study was to investigate whether the offline ART strategy is necessary for an online IGRT protocol and to evaluate the benefit of the hybrid strategy. First, to investigate the rationale of the hybrid strategy, 592 cone-beam-computed tomography (CBCT) images taken before and after each fraction for an online IGRT protocol from 16 patients were analyzed. Specifically, the characteristics of prostate rotation were analyzed. It was found that there exist systematic inter-fractional prostate rotations, and they are patient specific. These rotations, if not corrected, are persistent through the treatment fraction, and rotations detected in early fractions are representative of those in later fractions. These findings suggest that the offline adaptive replanning strategy is beneficial to the online IGRT protocol with further margin reductions. Second, to quantitatively evaluate the benefit of the hybrid strategy, 412 repeated helical CT scans from 25 patients during the course of treatment were included in the replanning study. Both low-risk patients (LRP, clinical target volume, CTV = prostate) and intermediate-risk patients (IRP, CTV = prostate + seminal vesicles) were included in the simulation. The contours of prostate and seminal vesicles were

  19. Application of Multi-Model CMIP5 Analysis in Future Drought Adaptation Strategies

    NASA Astrophysics Data System (ADS)

    Casey, M.; Luo, L.; Lang, Y.

    2014-12-01

    Drought influences the efficacy of numerous natural and artificial systems including species diversity, agriculture, and infrastructure. Global climate change raises concerns that extend well beyond atmospheric and hydrological disciplines - as climate changes with time, the need for system adaptation becomes apparent. Drought, as a natural phenomenon, is typically defined relative to the climate in which it occurs. Typically a 30-year reference time frame (RTF) is used to determine the severity of a drought event. This study investigates the projected future droughts over North America with different RTFs. Confidence in future hydroclimate projection is characterized by the agreement of long term (2005-2100) multi-model precipitation (P) and temperature (T) projections within the Coupled model Intercomparison Project Phase 5 (CMIP5). Drought severity and the propensity of extreme conditions are measured by the multi-scalar, probabilistic, RTF-based Standard Precipitation Index (SPI) and Standard Precipitation Evapotranspiration Index (SPEI). SPI considers only P while SPEI incorporates Evapotranspiration (E) via T; comparing the two reveals the role of temperature change in future hydroclimate change. Future hydroclimate conditions, hydroclimate extremity, and CMIP5 model agreement are assessed for each Representative Concentration Pathway (RCP 2.6, 4.5, 6.0, 8.5) in regions throughout North America for the entire year and for the boreal seasons. In addition, multiple time scales of SPI and SPEI are calculated to characterize drought at time scales ranging from short to long term. The study explores a simple, standardized method for considering adaptation in future drought assessment, which provides a novel perspective to incorporate adaptation with climate change. The result of the analysis is a multi-dimension, probabilistic summary of the hydrological (P, E) environment a natural or artificial system must adapt to over time. Studies similar to this with

  20. Adaptation and Validation of the Teacher Emotional Labour Strategy Scale in China

    ERIC Educational Resources Information Center

    Yin, Hongbiao

    2012-01-01

    The present study reports the adaptation and validation of the Teacher Emotional Labour Strategy Scale (TELSS) as tested on samples of 633 Beijing teachers and 648 Chongqing teachers in Chinese mainland. Results show that the 13-item TELSS adapted for this study had good internal consistency on three subscales which measure three types of teacher…

  1. Adaptive Fourier decomposition based ECG denoising.

    PubMed

    Wang, Ze; Wan, Feng; Wong, Chi Man; Zhang, Liming

    2016-10-01

    A novel ECG denoising method is proposed based on the adaptive Fourier decomposition (AFD). The AFD decomposes a signal according to its energy distribution, thereby making this algorithm suitable for separating pure ECG signal and noise with overlapping frequency ranges but different energy distributions. A stop criterion for the iterative decomposition process in the AFD is calculated on the basis of the estimated signal-to-noise ratio (SNR) of the noisy signal. The proposed AFD-based method is validated by the synthetic ECG signal using an ECG model and also real ECG signals from the MIT-BIH Arrhythmia Database both with additive Gaussian white noise. Simulation results of the proposed method show better performance on the denoising and the QRS detection in comparing with major ECG denoising schemes based on the wavelet transform, the Stockwell transform, the empirical mode decomposition, and the ensemble empirical mode decomposition.

  2. Competition and time-dependent behavior in spatial iterated prisoner’s dilemma incorporating adaptive zero-determinant strategies

    NASA Astrophysics Data System (ADS)

    Li, Yong; Xu, Chen; Liu, Jie; Hui, Pak Ming

    2016-10-01

    We propose and study the competitiveness of a class of adaptive zero-determinant strategies (ZDSs) in a population with spatial structure against four classic strategies in iterated prisoner’s dilemma. Besides strategy updating via a probabilistic mechanism by imitating the strategy of a better performing opponent, players using the ZDSs can also adapt their strategies to take advantage of their local competing environment with another probability. The adapted ZDSs could be extortionate-like to avoid being continually cheated by defectors or to take advantage of unconditional cooperators. The adapted ZDSs could also be a compliance strategy so as to cooperate with the conditionally cooperative players. This flexibility makes adaptive ZDSs more competitive than nonadaptive ZDSs. Results show that adaptive ZDSs can either dominate over other strategies or at least coexist with them when the ZDSs are allowed to adapt more readily than to imitate other strategies. The effectiveness of the adaptive ZDSs relies on how fast they can adapt to the competing environment before they are replaced by other strategies. The adaptive ZDSs generally work well as they could adapt gradually and make use of other strategies for suppressing their enemies. When adaptation happens more readily than imitation for the ZDSs, they outperform other strategies over a wide range of cost-to-benefit ratios.

  3. On Adaptive Extended Compatibility Changing Type of Product Design Strategy

    NASA Astrophysics Data System (ADS)

    Wenwen, Jiang; Zhibin, Xie

    The article uses research ways of Enterprise localization and enterprise's development course to research strategy of company's product design and development. It announces at different stages for development, different kinds of enterprises will adopt product design and development policies of different modes. It also announces close causality between development course of company and central technology and product. The result indicated enterprises in leading position in market, technology and brand adopt pioneer strategy type of product research and development. These enterprise relying on the large-scale leading enterprise offering a complete set service adopts the passively duplicating type tactic of product research and development. Some enterprise in part of advantage in technology, market, management or brand adopt following up strategy of product research and development. The enterprises with relative advantage position adopt the strategy of technology applied taking optimizing services as centre in product research and development in fields of brand culture and market service.

  4. First Clinical Release of an Online, Adaptive, Aperture-Based Image-Guided Radiotherapy Strategy in Intensity-Modulated Radiotherapy to Correct for Inter- and Intrafractional Rotations of the Prostate

    SciTech Connect

    Deutschmann, Heinz; Kametriser, Gerhard; Steininger, Philipp; Scherer, Philipp; Schoeller, Helmut; Gaisberger, Christoph; Mooslechner, Michaela; Mitterlechner, Bernhard; Weichenberger, Harald; Fastner, Gert; Wurstbauer, Karl; Jeschke, Stephan; Forstner, Rosemarie; Sedlmayer, Felix

    2012-08-01

    Purpose: We developed and evaluated a correction strategy for prostate rotations using direct adaptation of segments in intensity-modulated radiotherapy (IMRT). Method and Materials: Implanted fiducials (four gold markers) were used to determine interfractional translations, rotations, and dilations of the prostate. We used hybrid imaging: The markers were automatically detected in two pretreatment planar X-ray projections; their actual position in three-dimensional space was reconstructed from these images at first. The structure set comprising prostate, seminal vesicles, and adjacent rectum wall was transformed accordingly in 6 degrees of freedom. Shapes of IMRT segments were geometrically adapted in a class solution forward-planning approach, derived within seconds on-site and treated immediately. Intrafractional movements were followed in MV electronic portal images captured on the fly. Results: In 31 of 39 patients, for 833 of 1013 fractions (supine, flat couch, knee support, comfortably full bladder, empty rectum, no intraprostatic marker migrations >2 mm of more than one marker), the online aperture adaptation allowed safe reduction of margins clinical target volume-planning target volume (prostate) down to 5 mm when only interfractional corrections were applied: Dominant L-R rotations were found to be 5.3 Degree-Sign (mean of means), standard deviation of means {+-}4.9 Degree-Sign , maximum at 30.7 Degree-Sign . Three-dimensional vector translations relative to skin markings were 9.3 {+-} 4.4 mm (maximum, 23.6 mm). Intrafractional movements in 7.7 {+-} 1.5 min (maximum, 15.1 min) between kV imaging and last beam's electronic portal images showed further L-R rotations of 2.5 Degree-Sign {+-} 2.3 Degree-Sign (maximum, 26.9 Degree-Sign ), and three-dimensional vector translations of 3.0 {+-}3.7 mm (maximum, 10.2 mm). Addressing intrafractional errors could further reduce margins to 3 mm. Conclusion: We demonstrated the clinical feasibility of an online

  5. The Use of Social Ecological Hotspots Mapping: Co-Developing Adaptation Strategies for Resource Management by Communities and Policy Makers

    NASA Astrophysics Data System (ADS)

    Alessa, L.

    2014-12-01

    Ultimately, adaptation is based on a set of trade-offs rather than optimal conditions, something that is rarely seen in messy social ecological systems (SES). In this talk, we discuss the role of spatial hot-spot mapping using social and biophysical data to understand the feedbacks in SES. We review the types of data needed, their means of acquisition and the analytic methods involved. In addition, we outline the challenges faced in co-developing this type of inquiry based on lessons learned from several long-term programs. Finally, we present the utility of SES hotspots in developing adaptation strategies on the ground by communities and policy makers.

  6. KNOWBOT; An adaptive data base interface

    SciTech Connect

    Heger, A.S.; Koen, B.U. . Dept. of Mechanical Engineering)

    1991-02-01

    This paper reports on an adaptive interface KNOWBOT designed to solve some of the problems that face the users of large centralized data bases. The interface applies the neural network approach to information retrieval from a data base. The data base is a subset of the Nuclear Plant Reliability Data System. The interface KNOWBOT preempts an existing data base interface and works in conjunction with it. By design, KNOWBOT starts as a tabula rasa but acquires knowledge through its interactions with the user and the data base. The interface uses its gained knowledge to personalize the data base retrieval process and to induce new queries. The interface also forgets the information that is no longer needed by the user. These self-organizing features of the interface reduce the scope of the data base to the subsets that are highly relevant to the user needs. A proof-of-principal version of this interface has been implemented in Common LISP on a Texas Instruments Explorer I workstation. Experiments with KNOWBOT have been successful in demonstrating the robustness of the model especially with induction and self-organization. This paper describes the design of KNOWBOT and presents some of the experimental results.

  7. Adaptive RED algorithm based on minority game

    NASA Astrophysics Data System (ADS)

    Wei, Jiaolong; Lei, Ling; Qian, Jingjing

    2007-11-01

    With more and more applications appearing and the technology developing in the Internet, only relying on terminal system can not satisfy the complicated demand of QoS network. Router mechanisms must be participated into protecting responsive flows from the non-responsive. Routers mainly use active queue management mechanism (AQM) to avoid congestion. In the point of interaction between the routers, the paper applies minority game to describe the interaction of the users and observes the affection on the length of average queue. The parameters α, β of ARED being hard to confirm, adaptive RED based on minority game can depict the interactions of main body and amend the parameter α, β of ARED to the best. Adaptive RED based on minority game optimizes ARED and realizes the smoothness of average queue length. At the same time, this paper extends the network simulator plat - NS by adding new elements. Simulation has been implemented and the results show that new algorithm can reach the anticipative objects.

  8. An Incremental Target-Adapted Strategy for Active Geometric Calibration of Projector-Camera Systems

    PubMed Central

    Chen, Chia-Yen; Chien, Hsiang-Jen

    2013-01-01

    The calibration of a projector-camera system is an essential step toward accurate 3-D measurement and environment-aware data projection applications, such as augmented reality. In this paper we present a two-stage easy-to-deploy strategy for robust calibration of both intrinsic and extrinsic parameters of a projector. Two key components of the system are the automatic generation of projected light patterns and the incremental calibration process. Based on the incremental strategy, the calibration process first establishes a set of initial parameters, and then it upgrades these parameters incrementally using the projection and captured images of dynamically-generated calibration patterns. The scene-driven light patterns allow the system to adapt itself to the pose of the calibration target, such that the difficulty in feature detection is greatly lowered. The strategy forms a closed-loop system that performs self-correction as more and more observations become available. Compared to the conventional method, which requires a time-consuming process for the acquisition of dense pixel correspondences, the proposed method deploys a homography-based coordinate computation, allowing the calibration time to be dramatically reduced. The experimental results indicate that an improvement of 70% in reprojection errors is achievable and 95% of the calibration time can be saved. PMID:23435056

  9. Adaptive DFT-based Interferometer Fringe Tracking

    NASA Technical Reports Server (NTRS)

    Wilson, Edward; Pedretti, Ettore; Bregman, Jesse; Mah, Robert W.; Traub, Wesley A.

    2004-01-01

    An automatic interferometer fringe tracking system has been developed, implemented, and tested at the Infrared Optical Telescope Array (IOTA) observatory at Mt. Hopkins, Arizona. The system can minimize the optical path differences (OPDs) for all three baselines of the Michelson stellar interferometer at IOTA. Based on sliding window discrete Fourier transform (DFT) calculations that were optimized for computational efficiency and robustness to atmospheric disturbances, the algorithm has also been tested extensively on off-line data. Implemented in ANSI C on the 266 MHz PowerPC processor running the VxWorks real-time operating system, the algorithm runs in approximately 2.0 milliseconds per scan (including all three interferograms), using the science camera and piezo scanners to measure and correct the OPDs. The adaptive DFT-based tracking algorithm should be applicable to other systems where there is a need to detect or track a signal with an approximately constant-frequency carrier pulse.

  10. Adaptive strategies of remote systems operators exposed to perturbed camera-viewing conditions

    NASA Technical Reports Server (NTRS)

    Stuart, Mark A.; Manahan, Meera K.; Bierschwale, John M.; Sampaio, Carlos E.; Legendre, A. J.

    1991-01-01

    This report describes a preliminary investigation of the use of perturbed visual feedback during the performance of simulated space-based remote manipulation tasks. The primary objective of this NASA evaluation was to determine to what extent operators exhibit adaptive strategies which allow them to perform these specific types of remote manipulation tasks more efficiently while exposed to perturbed visual feedback. A secondary objective of this evaluation was to establish a set of preliminary guidelines for enhancing remote manipulation performance and reducing the adverse effects. These objectives were accomplished by studying the remote manipulator performance of test subjects exposed to various perturbed camera-viewing conditions while performing a simulated space-based remote manipulation task. Statistical analysis of performance and subjective data revealed that remote manipulation performance was adversely affected by the use of perturbed visual feedback and performance tended to improve with successive trials in most perturbed viewing conditions.

  11. Acculturation Strategies, Social Support, and Cross-Cultural Adaptation: A Mediation Analysis

    ERIC Educational Resources Information Center

    Ng, Ting Kin; Tsang, Kwok Kuen; Lian, Yi

    2013-01-01

    Previous acculturation research has established the influences of acculturation strategies and social support on cross-cultural adaptation. The present study attempted to elaborate these direct associations by proposing that social support and the use of the integration and marginalization strategies might affect psychological adaptation…

  12. Adaptation strategies to climate change and climate variability: a comparative study between seven contrasting river basins.

    NASA Astrophysics Data System (ADS)

    Droogers, P.

    2003-04-01

    Climate change and climate variability is and will have a tremendous impact on hydrology and consequently on food security and environmental protection. From the four major components in climate change and climate variability studies, projection, mitigation, impact and adaptation, has the latter so far received less attention than the other three. An international collaboration of ten institutions is comparing adaptation strategies between contrasting basins ranging from wet to dry and from poor to rich. Basins included are: Mekong, Walawe (Sri Lanka), Rhine, Sacramento, Syr Darya, Volta, and Zayandeh (Iran). Simulation models at basin and field scale have been set up and possible adaptation strategies are explored by these models. Preliminary results indicate that appropriate adaptation strategies are different between these seven contrasting basins. It is also clear that these adaptation strategies should focus on increased variability rather than on the overall change of the mean. The focus was hereby not only on an increase in variation but especially on the number of successive dry and wet years. Results show that the studies on these adaptation strategies could not be performed only at one scale, but that a combination of field scale as well as basin scale analysis is essential.

  13. Adaptive PCA based fault diagnosis scheme in imperial smelting process.

    PubMed

    Hu, Zhikun; Chen, Zhiwen; Gui, Weihua; Jiang, Bin

    2014-09-01

    In this paper, an adaptive fault detection scheme based on a recursive principal component analysis (PCA) is proposed to deal with the problem of false alarm due to normal process changes in real process. Our further study is also dedicated to develop a fault isolation approach based on Generalized Likelihood Ratio (GLR) test and Singular Value Decomposition (SVD) which is one of general techniques of PCA, on which the off-set and scaling fault can be easily isolated with explicit off-set fault direction and scaling fault classification. The identification of off-set and scaling fault is also applied. The complete scheme of PCA-based fault diagnosis procedure is proposed. The proposed scheme is first applied to Imperial Smelting Process, and the results show that the proposed strategies can be able to mitigate false alarms and isolate faults efficiently.

  14. Flexible stocking strategies for adapting to climatic variability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a result of precipitation-induced variability on forage production, ranchers have difficulty matching animal demand with forage availability in their operations. Flexible stocking strategies could more effectively use extra forage in highly productive years and limit risk of overgrazing during dr...

  15. Strategies for flood hazard adaptation in drought affected regions of Afghanistan

    NASA Astrophysics Data System (ADS)

    Schleupner, Christine

    2010-05-01

    continue to impact upon society by creating stresses for specific vulnerable groups. This study discusses and compares existing policies, legislations and strategies considering flood adaptation planning in Afghanistan. It reviews available Flood Hazard Maps and reflects on regional adaptation options. Present and future vulnerability to flooding is assessed through a GIS-based model by using scenario techniques. A strategy is developed how to implement measures into regional and integrated water resource management planning. In general, not a single but the selection of multiple measures will be successful in pro-active planning for climate change adaptation. In this regard a continuous consultation with stakeholders needs to take place to address their demands. Thus the results of this study cannot give solutions but might build the basis for recommended active planning processes.

  16. Failure of Anisotropic Unstructured Mesh Adaption Based on Multidimensional Residual Minimization

    NASA Technical Reports Server (NTRS)

    Wood, William A.; Kleb, William L.

    2003-01-01

    An automated anisotropic unstructured mesh adaptation strategy is proposed, implemented, and assessed for the discretization of viscous flows. The adaption criteria is based upon the minimization of the residual fluctuations of a multidimensional upwind viscous flow solver. For scalar advection, this adaption strategy has been shown to use fewer grid points than gradient based adaption, naturally aligning mesh edges with discontinuities and characteristic lines. The adaption utilizes a compact stencil and is local in scope, with four fundamental operations: point insertion, point deletion, edge swapping, and nodal displacement. Evaluation of the solution-adaptive strategy is performed for a two-dimensional blunt body laminar wind tunnel case at Mach 10. The results demonstrate that the strategy suffers from a lack of robustness, particularly with regard to alignment of the bow shock in the vicinity of the stagnation streamline. In general, constraining the adaption to such a degree as to maintain robustness results in negligible improvement to the solution. Because the present method fails to consistently or significantly improve the flow solution, it is rejected in favor of simple uniform mesh refinement.

  17. Real-time nutrient monitoring in rivers: adaptive sampling strategies, technological challenges and future directions

    NASA Astrophysics Data System (ADS)

    Blaen, Phillip; Khamis, Kieran; Lloyd, Charlotte; Bradley, Chris

    2016-04-01

    Excessive nutrient concentrations in river waters threaten aquatic ecosystem functioning and can pose substantial risks to human health. Robust monitoring strategies are therefore required to generate reliable estimates of river nutrient loads and to improve understanding of the catchment processes that drive spatiotemporal patterns in nutrient fluxes. Furthermore, these data are vital for prediction of future trends under changing environmental conditions and thus the development of appropriate mitigation measures. In recent years, technological developments have led to an increase in the use of continuous in-situ nutrient analysers, which enable measurements at far higher temporal resolutions than can be achieved with discrete sampling and subsequent laboratory analysis. However, such instruments can be costly to run and difficult to maintain (e.g. due to high power consumption and memory requirements), leading to trade-offs between temporal and spatial monitoring resolutions. Here, we highlight how adaptive monitoring strategies, comprising a mixture of temporal sample frequencies controlled by one or more 'trigger variables' (e.g. river stage, turbidity, or nutrient concentration), can advance our understanding of catchment nutrient dynamics while simultaneously overcoming many of the practical and economic challenges encountered in typical in-situ river nutrient monitoring applications. We present examples of short-term variability in river nutrient dynamics, driven by complex catchment behaviour, which support our case for the development of monitoring systems that can adapt in real-time to rapid environmental changes. In addition, we discuss the advantages and disadvantages of current nutrient monitoring techniques, and suggest new research directions based on emerging technologies and highlight how these might improve: 1) monitoring strategies, and 2) understanding of linkages between catchment processes and river nutrient fluxes.

  18. Adaptive resistance: A tumor strategy to evade immune attack

    PubMed Central

    Yao, Sheng; Chen, Lieping

    2014-01-01

    A dilemma in cancer immunology is that, although patients often develop active anti-tumor immune responses, the tumor still outgrows. It has become clear that under the pressure of the host’s immune system, cancer cells have adapted elaborate tactics to reduce their immunogenicity (also known as immunoselection) and/or to actively suppress immune cells and promote immune tolerance (also known as immunosubversion). In this issue of the European Journal of Immunology, Dolen and Esendagli [Eur. J. Immunol. 2013. 43: 747–757] show that acute myeloid leukemia (AML) cells develop an adaptive immune phenotype switching mechanism: In response to attack by activated T cells, the leukemia cells quickly downregulate the T-cell costimulatory ligand B7-H2 and reciprocally upregulate the coinhibitory ligands B7-H1 and B7-DC in order to shut down T-cell activation via the PD-1 pathway. These novel findings and their relevance for cancer immunotherapy, especially potential applications in PD-1 check-point blockade therapy are discussed in this Commentary. PMID:23381914

  19. Using a social justice and health framework to assess European climate change adaptation strategies.

    PubMed

    Boeckmann, Melanie; Zeeb, Hajo

    2014-11-28

    Climate change puts pressure on existing health vulnerabilities through higher frequency of extreme weather events, changes in disease vector distribution or exacerbated air pollution. Climate change adaptation policies may hold potential to reduce societal inequities. We assessed the role of public health and social justice in European climate change adaptation using a three-fold approach: a document analysis, a critical discourse analysis of a subgroup of strategies, and a ranking of strategies against our social justice framework. The ranking approach favored planning that includes various adaptation types, social issues and infrastructure changes. Themes on values identified in the five subgroup documents showed that risks are perceived as contradictory, technology is viewed as savior, responsibilities need to be negotiated, and social justice is advocated by only a few countries. Of 21 strategy documents assessed overall, those from Austria, England and Sweden received the highest scores in the ranking. Our qualitative assessment showed that in European adaptation planning, progress could still be made through community involvement into adaptation decisions, consistent consideration of social and demographic determinants, and a stronger link between infrastructural adaptation and the health sector. Overall, a social justice framework can serve as an evaluation guideline for adaptation policy documents.

  20. Using a Social Justice and Health Framework to Assess European Climate Change Adaptation Strategies

    PubMed Central

    Boeckmann, Melanie; Zeeb, Hajo

    2014-01-01

    Climate change puts pressure on existing health vulnerabilities through higher frequency of extreme weather events, changes in disease vector distribution or exacerbated air pollution. Climate change adaptation policies may hold potential to reduce societal inequities. We assessed the role of public health and social justice in European climate change adaptation using a three-fold approach: a document analysis, a critical discourse analysis of a subgroup of strategies, and a ranking of strategies against our social justice framework. The ranking approach favored planning that includes various adaptation types, social issues and infrastructure changes. Themes on values identified in the five subgroup documents showed that risks are perceived as contradictory, technology is viewed as savior, responsibilities need to be negotiated, and social justice is advocated by only a few countries. Of 21 strategy documents assessed overall, those from Austria, England and Sweden received the highest scores in the ranking. Our qualitative assessment showed that in European adaptation planning, progress could still be made through community involvement into adaptation decisions, consistent consideration of social and demographic determinants, and a stronger link between infrastructural adaptation and the health sector. Overall, a social justice framework can serve as an evaluation guideline for adaptation policy documents. PMID:25464133

  1. Weighted log-rank statistic to compare shared-path adaptive treatment strategies.

    PubMed

    Kidwell, Kelley M; Wahed, Abdus S

    2013-04-01

    Adaptive treatment strategies (ATSs) more closely mimic the reality of a physician's prescription process where the physician prescribes a medication to his/her patient, and based on that patient's response to the medication, modifies the treatment. Two-stage randomization designs, more generally, sequential multiple assignment randomization trial designs, are useful to assess ATSs where the interest is in comparing the entire sequence of treatments, including the patient's intermediate response. In this paper, we introduce the notion of shared-path and separate-path ATSs and propose a weighted log-rank statistic to compare overall survival distributions of multiple two-stage ATSs, some of which may be shared-path. Large sample properties of the statistic are derived and the type I error rate and power of the test are compared with the standard log-rank test through simulation. PMID:23178734

  2. Inter-joint coupling strategy during adaptation to novel viscous loads in human arm movement.

    PubMed

    Debicki, D B; Gribble, P L

    2004-08-01

    When arm movements are perturbed by a load, how does the nervous system adjust control signals to reduce error? While it has been shown that the nervous system is capable of compensating for the effects of limb dynamics and external forces, the strategies used to adapt to novel loads are not well understood. We used a robotic exoskeleton [kinesiological instrument for normal and altered reaching movements (KINARM)] to apply novel loads to the arm during single-joint elbow flexions in the horizontal plane (shoulder rotation was allowed). Loads varied in magnitude with the instantaneous velocity of elbow flexion, and were applied to the shoulder in experiment 1 (interaction loads) and the elbow in experiment 2 (direct loads). Initial exposure to both interaction and direct loads resulted in perturbations at both joints, even though the load was applied to only a single joint. Subjects tended to correct for the kinematics of the elbow joint while perturbations at the shoulder persisted. Electromyograms (EMGs) and computed muscle torque showed that subjects modified muscle activity at the elbow to reduce elbow positional deviations. Shoulder muscle activity was also modified; however, these changes were always in the same direction as those at the elbow. Current models of motor control based on inverse-dynamics calculations and force-control, as well as models based on positional control, predict an uncoupling of shoulder and elbow muscle torques for adaptation to these loads. In contrast, subjects in this study adopted a simple strategy of modulating the natural coupling that exists between elbow and shoulder muscle torque during single-joint elbow movements.

  3. Inter-joint coupling strategy during adaptation to novel viscous loads in human arm movement.

    PubMed

    Debicki, D B; Gribble, P L

    2004-08-01

    When arm movements are perturbed by a load, how does the nervous system adjust control signals to reduce error? While it has been shown that the nervous system is capable of compensating for the effects of limb dynamics and external forces, the strategies used to adapt to novel loads are not well understood. We used a robotic exoskeleton [kinesiological instrument for normal and altered reaching movements (KINARM)] to apply novel loads to the arm during single-joint elbow flexions in the horizontal plane (shoulder rotation was allowed). Loads varied in magnitude with the instantaneous velocity of elbow flexion, and were applied to the shoulder in experiment 1 (interaction loads) and the elbow in experiment 2 (direct loads). Initial exposure to both interaction and direct loads resulted in perturbations at both joints, even though the load was applied to only a single joint. Subjects tended to correct for the kinematics of the elbow joint while perturbations at the shoulder persisted. Electromyograms (EMGs) and computed muscle torque showed that subjects modified muscle activity at the elbow to reduce elbow positional deviations. Shoulder muscle activity was also modified; however, these changes were always in the same direction as those at the elbow. Current models of motor control based on inverse-dynamics calculations and force-control, as well as models based on positional control, predict an uncoupling of shoulder and elbow muscle torques for adaptation to these loads. In contrast, subjects in this study adopted a simple strategy of modulating the natural coupling that exists between elbow and shoulder muscle torque during single-joint elbow movements. PMID:15056688

  4. A Structure-Adaptive Hybrid RBF-BP Classifier with an Optimized Learning Strategy

    PubMed Central

    Wen, Hui; Xie, Weixin; Pei, Jihong

    2016-01-01

    This paper presents a structure-adaptive hybrid RBF-BP (SAHRBF-BP) classifier with an optimized learning strategy. SAHRBF-BP is composed of a structure-adaptive RBF network and a BP network of cascade, where the number of RBF hidden nodes is adjusted adaptively according to the distribution of sample space, the adaptive RBF network is used for nonlinear kernel mapping and the BP network is used for nonlinear classification. The optimized learning strategy is as follows: firstly, a potential function is introduced into training sample space to adaptively determine the number of initial RBF hidden nodes and node parameters, and a form of heterogeneous samples repulsive force is designed to further optimize each generated RBF hidden node parameters, the optimized structure-adaptive RBF network is used for adaptively nonlinear mapping the sample space; then, according to the number of adaptively generated RBF hidden nodes, the number of subsequent BP input nodes can be determined, and the overall SAHRBF-BP classifier is built up; finally, different training sample sets are used to train the BP network parameters in SAHRBF-BP. Compared with other algorithms applied to different data sets, experiments show the superiority of SAHRBF-BP. Especially on most low dimensional and large number of data sets, the classification performance of SAHRBF-BP outperforms other training SLFNs algorithms. PMID:27792737

  5. Numerous strategies but limited implementation guidance in US local adaptation plans

    NASA Astrophysics Data System (ADS)

    Woodruff, Sierra C.; Stults, Missy

    2016-08-01

    Adaptation planning offers a promising approach for identifying and devising solutions to address local climate change impacts. Yet there is little empirical understanding of the content and quality of these plans. We use content analysis to evaluate 44 local adaptation plans in the United States and multivariate regression to examine how plan quality varies across communities. We find that plans draw on multiple data sources to analyse future climate impacts and include a breadth of strategies. Most plans, however, fail to prioritize impacts and strategies or provide detailed implementation processes, raising concerns about whether adaptation plans will translate into on-the-ground reductions in vulnerability. Our analysis also finds that plans authored by the planning department and those that engaged elected officials in the planning process were of higher quality. The results provide important insights for practitioners, policymakers and scientists wanting to improve local climate adaptation planning and action.

  6. An Adaptive Feedback and Review Paradigm for Computer-Based Drills.

    ERIC Educational Resources Information Center

    Siegel, Martin A.; Misselt, A. Lynn

    The Corrective Feedback Paradigm (CFP), which has been refined and expanded through use on the PLATO IV Computer-Based Education System, is based on instructional design strategies implied by stimulus-locus analyses, direct instruction, and instructional feedback methods. Features of the paradigm include adaptive feedback techniques with…

  7. [Adaptive and Maladaptive Strategies of Emotion Regulation in Adolescents with ADHD].

    PubMed

    Lange, Sarah; Tröster, Heinrich

    2016-01-01

    The present study investigated differences between adolescents with ADHD and control subjects in their adaptive und maladaptive regulation of negative emotions. We assessed emotion regulation strategies using the German self-report questionnaire FEEL-KJ in a sample of adolescents (between 11 and 18 years) with ADHD (disturbance of activity, impulsivity and attention: n = 32, hyperkinetic conduct disorder: n = 26) and controls (n = 58). We found that adolescents with ADHD reported using less adaptive strategies for dealing with negative emotions than control subjects. No effects were found for maladaptive emotion regulation strategies for anger, fear and sadness. Our findings indicate that adolescents with ADHD should be encouraged in the development of adaptive emotion regulation. PMID:27184787

  8. An adaptive grid refinement strategy for the simulation of negative streamers

    SciTech Connect

    Montijn, C. . E-mail: carolynne.montijn@cwi.nl; Hundsdorfer, W. . E-mail: willem.hundsdorfer@cwi.nl; Ebert, U. . E-mail: ute.ebert@cwi.nl

    2006-12-10

    The evolution of negative streamers during electric breakdown of a non-attaching gas can be described by a two-fluid model for electrons and positive ions. It consists of continuity equations for the charged particles including drift, diffusion and reaction in the local electric field, coupled to the Poisson equation for the electric potential. The model generates field enhancement and steep propagating ionization fronts at the tip of growing ionized filaments. An adaptive grid refinement method for the simulation of these structures is presented. It uses finite volume spatial discretizations and explicit time stepping, which allows the decoupling of the grids for the continuity equations from those for the Poisson equation. Standard refinement methods in which the refinement criterion is based on local error monitors fail due to the pulled character of the streamer front that propagates into a linearly unstable state. We present a refinement method which deals with all these features. Tests on one-dimensional streamer fronts as well as on three-dimensional streamers with cylindrical symmetry (hence effectively 2D for numerical purposes) are carried out successfully. Results on fine grids are presented, they show that such an adaptive grid method is needed to capture the streamer characteristics well. This refinement strategy enables us to adequately compute negative streamers in pure gases in the parameter regime where a physical instability appears: branching streamers.

  9. Climate Variability, Andean Livelihood Strategies, Development and Adaptation in the Andean Region

    NASA Astrophysics Data System (ADS)

    Valdivia, C.; Quiroz, R.; Zorogastua, P.; Baigorrea, G.

    2002-05-01

    Development programs in the Andes have failed to recognize climate variability as an element that is crucial to the adoption of new alternatives. Dairy, potatoes, improved sheep, forages are all part of the history of development in this region. A combination of climate variability, changes in the economy, the political environment, and land tenure reform shape rural livelihoods and welfare. Diversification, linking to markets, and networking are some elements that contribute to the resilience of families in the Andes. Strategies change, are flexible, and may incorporate non-agricultural activities. While some farmers are able to improve their welfare through the life cycle, others become poorer. Climate variability increases the vulnerability of some groups; in other cases, because of diversification and assets, households build economic portfolios that are more resilient to the elements. The many projects provide insights into how in the long run households improve their environment, hinting at mechanisms to adapt to climate change. In order to understand changing composition of portfolios in future scenarios of spatial heterogeneous areas such as mountains (Andes), estimates of models predicting climate change at a global scale are not useful because their resolution. Therefore, downscaling tools are useful. Spatial heterogeneity is assessed through agroecozoning. Both production and the impact on some environmental indicators are simulated through process-based models, for the Ilave-Huenque watershed in Peru that help in discussing scenarios of adaptation.

  10. Temporal features of postural adaptation strategy to prolonged and repeatable balance perturbation.

    PubMed

    Schmid, Micaela; Sozzi, Stefania

    2016-08-15

    Aim of this study was to get insight into the features of the postural adaptation process, occurring during a continuous 3-min and 0.6Hz horizontal sinusoidal oscillation of the body support base. We hypothesized an ongoing temporal organization of the balancing strategy that gradually becomes fine-tuned and more coordinated with the platform movement. The trial was divided into oscillation cycles and for each cycle: leg muscles activity and temporal relationship between Centre of Mass and Centre of Pressure A-P position were analyzed. The results of each cycle were grouped in time-windows of 10 successive cycles (time windows of 16.6s). Muscle activity was initially prominent and diminished progressively. The major burst of Tibialis Anterior (TA) muscle always occurred at the same time instant of the platform oscillation cycle, in advance with respect to the platform posterior turning point. This burst produced a body forward rotation that was delayed throughout the task. During prolonged and repeatable balance perturbation, an ongoing postural adaptation process occurs. When the effects of the perturbation become predictable, the CNS scales the level of muscle activity to counteracting the destabilizing effects of the perturbations. Furthermore, the CNS tunes the kinematics and the kinetic responses optimally by slightly delaying the onset of the body forward rotation, maintaining unchanged the time-pattern of postural muscle activation. PMID:27291456

  11. Temporal features of postural adaptation strategy to prolonged and repeatable balance perturbation.

    PubMed

    Schmid, Micaela; Sozzi, Stefania

    2016-08-15

    Aim of this study was to get insight into the features of the postural adaptation process, occurring during a continuous 3-min and 0.6Hz horizontal sinusoidal oscillation of the body support base. We hypothesized an ongoing temporal organization of the balancing strategy that gradually becomes fine-tuned and more coordinated with the platform movement. The trial was divided into oscillation cycles and for each cycle: leg muscles activity and temporal relationship between Centre of Mass and Centre of Pressure A-P position were analyzed. The results of each cycle were grouped in time-windows of 10 successive cycles (time windows of 16.6s). Muscle activity was initially prominent and diminished progressively. The major burst of Tibialis Anterior (TA) muscle always occurred at the same time instant of the platform oscillation cycle, in advance with respect to the platform posterior turning point. This burst produced a body forward rotation that was delayed throughout the task. During prolonged and repeatable balance perturbation, an ongoing postural adaptation process occurs. When the effects of the perturbation become predictable, the CNS scales the level of muscle activity to counteracting the destabilizing effects of the perturbations. Furthermore, the CNS tunes the kinematics and the kinetic responses optimally by slightly delaying the onset of the body forward rotation, maintaining unchanged the time-pattern of postural muscle activation.

  12. Paradoxical cardiovascular effects of implementing adaptive emotion regulation strategies in generalized anxiety disorder.

    PubMed

    Aldao, Amelia; Mennin, Douglas S

    2012-02-01

    Recent models of generalized anxiety disorder (GAD) have expanded on Borkovec's avoidance theory by delineating emotion regulation deficits associated with the excessive worry characteristic of this disorder (see Behar, DiMarco, Hekler, Mohlman, & Staples, 2009). However, it has been difficult to determine whether emotion regulation is simply a useful heuristic for the avoidant properties of worry or an important extension to conceptualizations of GAD. Some of this difficulty may arise from a focus on purported maladaptive regulation strategies, which may be confounded with symptomatic distress components of the disorder (such as worry). We examined the implementation of adaptive regulation strategies by participants with and without a diagnosis of GAD while watching emotion-eliciting film clips. In a between-subjects design, participants were randomly assigned to accept, reappraise, or were not given specific regulation instructions. Implementation of adaptive regulation strategies produced differential effects in the physiological (but not subjective) domain across diagnostic groups. Whereas participants with GAD demonstrated lower cardiac flexibility when implementing adaptive regulation strategies than when not given specific instructions on how to regulate, healthy controls showed the opposite pattern, suggesting they benefited from the use of adaptive regulation strategies. We discuss the implications of these findings for the delineation of emotion regulation deficits in psychopathology. PMID:22218164

  13. Different Responses to Heat Shock Stress Revealed Heteromorphic Adaptation Strategy of Pyropia haitanensis (Bangiales, Rhodophyta)

    PubMed Central

    Zhu, Zhujun; Yang, Rui; Qian, Feijian; Chen, Haimin; Yan, Xiaojun

    2014-01-01

    Pyropia has a unique heteromorphic life cycle with alternation stages between thallus and conchocelis, which lives at different water temperatures in different seasons. To better understand the different adaptation strategies for temperature stress, we tried to observe comparative biochemical changes of Pyropia haitanensis based on a short term heat shock model. The results showed that: (1) At normal temperature, free-living conchocelis contains significantly higher levels of H2O2, fatty acid-derived volatiles, the copy number of Phrboh and Phhsp70 genes,the activities of NADPH oxidase and floridoside than those in thallus. The released H2O2 and NADPH oxidase activity of conchocelis were more than 7 times higher than those of thallus. The copy number of Phrboh in conchocelis was 32 times that in thallus. (2) After experiencing heat shock at 35°C for 30 min, the H2O2 contents, the mRNA levels of Phrboh and Phhsp70, NADPH oxidase activity and the floridoside content in thallus were all significantly increased. The mRNA levels of Phrboh increased 5.78 times in 5 min, NADPH oxidase activity increased 8.45 times in 20 min. (3) Whereas, in conchocelis, the changes in fatty acids and their down-stream volatiles predominated, significantly increasing levels of saturated fatty acids and decreasing levels of polyunsaturated fatty acids occurred, and the 8-carbon volatiles were accumulated. However, the changes in H2O2 content and expression of oxidant-related genes and enzymatic activity were not obvious. Overall, these results indicate that conchocelis maintains a high level of active protective apparatus to endure its survival at high temperature, while thallus exhibit typical stress responses to heat shock. It is concluded that Pyropia haitanensis has evolved a delicate strategy for temperature adaptation for its heteromorphic life cycle. PMID:24709783

  14. SU-F-BRF-07: Impact of Different Patient Setup Strategies in Adaptive Radiation Therapy with Simultaneous Integrated Volume-Adapted Boost of NSCLC

    SciTech Connect

    Balik, S; Weiss, E; Sleeman, W; Wu, Y; Hugo, G; Dogan, N; Fatyga, M

    2014-06-15

    Purpose: To evaluate the potential impact of several setup error correction strategies on a proposed image-guided adaptive radiotherapy strategy for locally advanced lung cancer. Methods: Daily 4D cone-beam CT and weekly 4D fan-beam CT images were acquired from 9 lung cancer patients undergoing concurrent chemoradiation therapy. Initial planning CT was deformably registered to daily CBCT images to generate synthetic treatment courses. An adaptive radiation therapy course was simulated using the weekly CT images with replanning twice and a hypofractionated, simultaneous integrated boost to a total dose of 66 Gy to the original PTV and either a 66 Gy (no boost) or 82 Gy (boost) dose to the boost PTV (ITV + 3mm) in 33 fractions with IMRT or VMAT. Lymph nodes (LN) were not boosted (prescribed to 66 Gy in both plans). Synthetic images were rigidly, bony (BN) or tumor and carina (TC), registered to the corresponding plan CT, dose was computed on these from adaptive replans (PLAN) and deformably accumulated back to the original planning CT. Cumulative D98% of CTV of PT (ITV for 82Gy) and LN, and normal tissue dose changes were analyzed. Results: Two patients were removed from the study due to large registration errors. For the remaining 7 patients, D98% for CTV-PT (ITV-PT for 82 Gy) and CTV-LN was within 1 Gy of PLAN for both 66 Gy and 82 Gy plans with both setup techniques. Overall, TC based setup provided better results, especially for LN coverage (p = 0.1 for 66Gy plan and p = 0.2 for 82 Gy plan, comparison of BN and TC), though not significant. Normal tissue dose constraints violated for some patients if constraint was barely achieved in PLAN. Conclusion: The hypofractionated adaptive strategy appears to be deliverable with soft tissue alignment for the evaluated margins and planning parameters. Research was supported by NIH P01CA116602.

  15. Understanding the adaptive growth strategy of Lactobacillus plantarum by in silico optimisation.

    PubMed

    Teusink, Bas; Wiersma, Anne; Jacobs, Leo; Notebaart, Richard A; Smid, Eddy J

    2009-06-01

    In the study of metabolic networks, optimization techniques are often used to predict flux distributions, and hence, metabolic phenotype. Flux balance analysis in particular has been successful in predicting metabolic phenotypes. However, an inherent limitation of a stoichiometric approach such as flux balance analysis is that it can predict only flux distributions that result in maximal yields. Hence, previous attempts to use FBA to predict metabolic fluxes in Lactobacillus plantarum failed, as this lactic acid bacterium produces lactate, even under glucose-limited chemostat conditions, where FBA predicted mixed acid fermentation as an alternative pathway leading to a higher yield. In this study we tested, however, whether long-term adaptation on an unusual and poor carbon source (for this bacterium) would select for mutants with optimal biomass yields. We have therefore adapted Lactobacillus plantarum to grow well on glycerol as its main growth substrate. After prolonged serial dilutions, the growth yield and corresponding fluxes were compared to in silico predictions. Surprisingly, the organism still produced mainly lactate, which was corroborated by FBA to indeed be optimal. To understand these results, constraint-based elementary flux mode analysis was developed that predicted 3 out of 2669 possible flux modes to be optimal under the experimental conditions. These optimal pathways corresponded very closely to the experimentally observed fluxes and explained lactate formation as the result of competition for oxygen by the other flux modes. Hence, these results provide thorough understanding of adaptive evolution, allowing in silico predictions of the resulting flux states, provided that the selective growth conditions favor yield optimization as the winning strategy.

  16. Adaptive muffler based on controlled flow valves.

    PubMed

    Šteblaj, Peter; Čudina, Mirko; Lipar, Primož; Prezelj, Jurij

    2015-06-01

    An adaptive muffler with a flexible internal structure is considered. Flexibility is achieved using controlled flow valves. The proposed adaptive muffler is able to adapt to changes in engine operating conditions. It consists of a Helmholtz resonator, expansion chamber, and quarter wavelength resonator. Different combinations of the control valves' states at different operating conditions define the main working principle. To control the valve's position, an active noise control approach was used. With the proposed muffler, the transmission loss can be increased by more than 10 dB in the selected frequency range. PMID:26093462

  17. Recruitment Strategies for Women in Nontraditional Careers. Adapted from Fair Recruitment Model and Strategies.

    ERIC Educational Resources Information Center

    Stitt, Beverly; Stitt, Tom

    This guide presents 21 one- or two-page recruitment strategies for women in nontraditional careers. Each entry includes sections on what, when, where, who, and how. Strategies included are: (1) attention-getter giveaways; (2) bias-fee brochure; (3) bias-free slide-tape; (4) "bring a friend" day; (5) brochures with utility bills; (6) craftperson…

  18. Evidence-Based Classroom Behaviour Management Strategies

    ERIC Educational Resources Information Center

    Parsonson, Barry S.

    2012-01-01

    This paper reviews a range of evidence-based strategies for application by teachers to reduce disruptive and challenging behaviours in their classrooms. These include a number of antecedent strategies intended to help minimise the emergence of problematic behaviours and a range of those which provide positive consequences for appropriate student…

  19. Adaptive surrogate model based multi-objective transfer trajectory optimization between different libration points

    NASA Astrophysics Data System (ADS)

    Peng, Haijun; Wang, Wei

    2016-10-01

    An adaptive surrogate model-based multi-objective optimization strategy that combines the benefits of invariant manifolds and low-thrust control toward developing a low-computational-cost transfer trajectory between libration orbits around the L1 and L2 libration points in the Sun-Earth system has been proposed in this paper. A new structure for a multi-objective transfer trajectory optimization model that divides the transfer trajectory into several segments and gives the dominations for invariant manifolds and low-thrust control in different segments has been established. To reduce the computational cost of multi-objective transfer trajectory optimization, a mixed sampling strategy-based adaptive surrogate model has been proposed. Numerical simulations show that the results obtained from the adaptive surrogate-based multi-objective optimization are in agreement with the results obtained using direct multi-objective optimization methods, and the computational workload of the adaptive surrogate-based multi-objective optimization is only approximately 10% of that of direct multi-objective optimization. Furthermore, the generating efficiency of the Pareto points of the adaptive surrogate-based multi-objective optimization is approximately 8 times that of the direct multi-objective optimization. Therefore, the proposed adaptive surrogate-based multi-objective optimization provides obvious advantages over direct multi-objective optimization methods.

  20. Strategies of Mesenchymal Invasion of Patient-derived Brain Tumors: Microenvironmental Adaptation

    PubMed Central

    Cha, Junghwa; Kang, Seok-Gu; Kim, Pilnam

    2016-01-01

    The high mortality in glioblastoma multiforme (GBM) patients is primarily caused by extensive infiltration into adjacent tissue and subsequent rapid recurrence. There are no clear therapeutic strategies that target the infiltrative subpopulation of GBM mass. Using mesenchymal mode of invasion, the GBM is known to widely infiltrate by interacting with various unique components within brain microenvironment such as hyaluronic acid (HA)-rich matrix and white matter tracts. However, it is unclear how these GBM microenvironments influence the strategies of mesenchymal invasion. We hypothesize that GBM has different strategies to facilitate such invasion through adaptation to their local microenvironment. Using our in vitro biomimetic microenvironment platform for three-dimensional GBM tumorspheres (TSs), we found that the strategies of GBM invasion were predominantly regulated by the HA-rich ECM microenvironment, showing marked phenotypic changes in the presence of HA, which were mainly mediated by HA synthase (HAS). Interestingly, after inhibition of the HAS gene, GBM switched their invasion strategies to a focal adhesion (FA)-mediated invasion. These results demonstrate that the microenvironmental adaptation allowed a flexible invasion strategy for GBM. Using our model, we suggest a new inhibitory pathway for targeting infiltrative GBM and propose an importance of multi-target therapy for GBM, which underwent microenvironmental adaptation. PMID:27108713

  1. Experimental Investigation of Human Adaptation to Change in Agent's Strategy through a Competitive Two-Player Game

    NASA Astrophysics Data System (ADS)

    Terada, Kazunori; Yamada, Seiji; Ito, Akira

    We conducted an experimental investigation on human adaptation to change in an agent's strategy through a competitive two-player game. Modeling the process of human adaptation to agents is important for designing intelligent interface agents and adaptive user interfaces that learn a user's preferences and behavior strategy. However, few studies on human adaptation to such an agent have been done. We propose a human adaptation model for a two-player game. We prepared an on-line experimental system in which a participant and an agent play a repeated penny-matching game with a bonus round. We then conducted experiments in which different opponent agents (human or robot) change their strategy during the game. The experimental results indicated that, as expected, there is an adaptation phase when a human is confronted with a change in the opponent agent's strategy, and adaptation is faster when a human is competing with robot than with another human.

  2. 78 FR 19514 - National Fish, Wildlife, and Plants Climate Adaptation Strategy

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-01

    ... May 24, 2011, notice of intent in the Federal Register (76 FR 30193). After this initial input was... 20, 2012 (77 FR 2996), for a 45-day public comment period. Comments received during the public... Fish and Wildlife Service National Fish, Wildlife, and Plants Climate Adaptation Strategy AGENCY:...

  3. Rangeland management strategies for adapting to climatic variability: Enhancing the positive and mitigating the negative effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland management strategies for adapting to climatic variability are needed to reduce enterprise risk, increase resilience of rangeland/grassland ecosystems and deliver sustainable provision of ecosystem goods (e.g., livestock production) and services (e.g., wildlife habitat) from western North ...

  4. Adapted Action Research as an Instructional Strategy in a Music Teacher Education Programme in Hong Kong

    ERIC Educational Resources Information Center

    Wong, Marina W. Y.

    2011-01-01

    This study explores how adapted action research could act as a catalyst for change in curriculum development and be used as an instructional strategy in a music teacher education programme to enhance the reflective practice of student-teachers. Two cases of in-service, part-time student-teachers of a music teacher programme who conducted an…

  5. Adaptive and Qualitative Changes in Encoding Strategy with Experience: Evidence from the Test-Expectancy Paradigm

    ERIC Educational Resources Information Center

    Finley, Jason R.; Benjamin, Aaron S.

    2012-01-01

    Three experiments demonstrated learners' abilities to adaptively and qualitatively accommodate their encoding strategies to the demands of an upcoming test. Stimuli were word pairs. In Experiment 1, test expectancy was induced for either cued recall (of targets given cues) or free recall (of targets only) across 4 study-test cycles of the same…

  6. The Effect of Adaptive Confidence Strategies in Computer-Assisted Instruction on Learning and Learner Confidence

    ERIC Educational Resources Information Center

    Warren, Richard Daniel

    2012-01-01

    The purpose of this research was to investigate the effects of including adaptive confidence strategies in instructionally sound computer-assisted instruction (CAI) on learning and learner confidence. Seventy-one general educational development (GED) learners recruited from various GED learning centers at community colleges in the southeast United…

  7. Strategies for Controlling Item Exposure in Computerized Adaptive Testing with the Generalized Partial Credit Model

    ERIC Educational Resources Information Center

    Davis, Laurie Laughlin

    2004-01-01

    Choosing a strategy for controlling item exposure has become an integral part of test development for computerized adaptive testing (CAT). This study investigated the performance of six procedures for controlling item exposure in a series of simulated CATs under the generalized partial credit model. In addition to a no-exposure control baseline…

  8. Knowledge-based control of an adaptive interface

    NASA Technical Reports Server (NTRS)

    Lachman, Roy

    1989-01-01

    The analysis, development strategy, and preliminary design for an intelligent, adaptive interface is reported. The design philosophy couples knowledge-based system technology with standard human factors approaches to interface development for computer workstations. An expert system has been designed to drive the interface for application software. The intelligent interface will be linked to application packages, one at a time, that are planned for multiple-application workstations aboard Space Station Freedom. Current requirements call for most Space Station activities to be conducted at the workstation consoles. One set of activities will consist of standard data management services (DMS). DMS software includes text processing, spreadsheets, data base management, etc. Text processing was selected for the first intelligent interface prototype because text-processing software can be developed initially as fully functional but limited with a small set of commands. The program's complexity then can be increased incrementally. The intelligent interface includes the operator's behavior and three types of instructions to the underlying application software are included in the rule base. A conventional expert-system inference engine searches the data base for antecedents to rules and sends the consequents of fired rules as commands to the underlying software. Plans for putting the expert system on top of a second application, a database management system, will be carried out following behavioral research on the first application. The intelligent interface design is suitable for use with ground-based workstations now common in government, industrial, and educational organizations.

  9. Adaptive backstepping sliding mode control with fuzzy monitoring strategy for a kind of mechanical system.

    PubMed

    Song, Zhankui; Sun, Kaibiao

    2014-01-01

    A novel adaptive backstepping sliding mode control (ABSMC) law with fuzzy monitoring strategy is proposed for the tracking-control of a kind of nonlinear mechanical system. The proposed ABSMC scheme combining the sliding mode control and backstepping technique ensure that the occurrence of the sliding motion in finite-time and the trajectory of tracking-error converge to equilibrium point. To obtain a better perturbation rejection property, an adaptive control law is employed to compensate the lumped perturbation. Furthermore, we introduce fuzzy monitoring strategy to improve adaptive capacity and soften the control signal. The convergence and stability of the proposed control scheme are proved by using Lyaponov's method. Finally, numerical simulations demonstrate the effectiveness of the proposed control scheme.

  10. Dosimetric and geometric evaluation of a hybrid strategy of offline adaptive planning and online image guidance for prostate cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Liu, Han; Wu, Qiuwen

    2011-08-01

    For prostate cancer patients, online image-guided (IG) radiotherapy has been widely used in clinic to correct the translational inter-fractional motion at each treatment fraction. For uncertainties that cannot be corrected online, such as rotation and deformation of the target volume, margins are still required to be added to the clinical target volume (CTV) for the treatment planning. Offline adaptive radiotherapy has been implemented to optimize the treatment for each individual patient based on the measurements at early stages of treatment process. It has been shown that offline adaptive radiotherapy can effectively reduce the required margin. Recently a hybrid strategy of offline adaptive replanning and online IG was proposed and the geometric evaluation was performed. It was found that the planning margins can further be reduced by 1-2 mm compared to online IG only strategy. The purpose of this study was to investigate the dosimetric benefits of such a hybrid strategy on the target and organs at risk. A total of 420 repeated helical computed tomography scans from 28 patients were included in the study. Both low-risk patients (LRP, CTV = prostate) and intermediate-risk patients (IRP, CTV = prostate + seminal vesicles, SV) were included in the simulation. Two registration methods, based on center-of-mass shift of prostate only and prostate plus SV, were performed for IRP. The intensity-modulated radiotherapy was used in the simulation. Criteria on both cumulative and fractional doses were evaluated. Furthermore, the geometric evaluation was extended to investigate the optimal number of fractions necessary to construct the internal target volume (ITV) for the hybrid strategy. The dosimetric margin improvement was smaller than its geometric counterpart and was in the range of 0-1 mm. The optimal number of fractions necessary for the ITV construction is 2 for LRPs and 3-4 for IRPs in a hypofractionation protocol. A new cumulative index of target volume was proposed

  11. Adapting to Adaptations: Behavioural Strategies that are Robust to Mutations and Other Organisational-Transformations.

    PubMed

    Egbert, Matthew D; Pérez-Mercader, Juan

    2016-01-01

    Genetic mutations, infection by parasites or symbionts, and other events can transform the way that an organism's internal state changes in response to a given environment. We use a minimalistic computational model to support an argument that by behaving "interoceptively," i.e. responding to internal state rather than to the environment, organisms can be robust to these organisational-transformations. We suggest that the robustness of interoceptive behaviour is due, in part, to the asymmetrical relationship between an organism and its environment, where the latter more substantially influences the former than vice versa. This relationship means that interoceptive behaviour can respond to the environment, the internal state and the interaction between the two, while exteroceptive behaviour can only respond to the environment. We discuss the possibilities that (i) interoceptive behaviour may play an important role of facilitating adaptive evolution (especially in the early evolution of primitive life) and (ii) interoceptive mechanisms could prove useful in efforts to create more robust synthetic life-forms. PMID:26743579

  12. Adapting to Adaptations: Behavioural Strategies that are Robust to Mutations and Other Organisational-Transformations

    PubMed Central

    Egbert, Matthew D.; Pérez-Mercader, Juan

    2016-01-01

    Genetic mutations, infection by parasites or symbionts, and other events can transform the way that an organism’s internal state changes in response to a given environment. We use a minimalistic computational model to support an argument that by behaving “interoceptively,” i.e. responding to internal state rather than to the environment, organisms can be robust to these organisational-transformations. We suggest that the robustness of interoceptive behaviour is due, in part, to the asymmetrical relationship between an organism and its environment, where the latter more substantially influences the former than vice versa. This relationship means that interoceptive behaviour can respond to the environment, the internal state and the interaction between the two, while exteroceptive behaviour can only respond to the environment. We discuss the possibilities that (i) interoceptive behaviour may play an important role of facilitating adaptive evolution (especially in the early evolution of primitive life) and (ii) interoceptive mechanisms could prove useful in efforts to create more robust synthetic life-forms. PMID:26743579

  13. Adaptive Rule Based Fetal QRS Complex Detection Using Hilbert Transform

    PubMed Central

    Ulusar, Umit D.; Govindan, R.B.; Wilson, James D.; Lowery, Curtis L.; Preissl, Hubert; Eswaran, Hari

    2010-01-01

    In this paper we introduce an adaptive rule based QRS detection algorithm using the Hilbert transform (adHQRS) for fetal magnetocardiography processing. Hilbert transform is used to combine multiple channel measurements and the adaptive rule based decision process is used to eliminate spurious beats. The algorithm has been tested with a large number of datasets and promising results were obtained. PMID:19964648

  14. Creating Evidence-Based Research in Adapted Physical Activity

    ERIC Educational Resources Information Center

    Reid, Greg; Bouffard, Marcel; MacDonald, Catherine

    2012-01-01

    Professional practice guided by the best research evidence is a usually referred to as evidence-based practice. The aim of the present paper is to describe five fundamental beliefs of adapted physical activity practices that should be considered in an 8-step research model to create evidence-based research in adapted physical activity. The five…

  15. Turbulent Output-Based Anisotropic Adaptation

    NASA Technical Reports Server (NTRS)

    Park, Michael A.; Carlson, Jan-Renee

    2010-01-01

    Controlling discretization error is a remaining challenge for computational fluid dynamics simulation. Grid adaptation is applied to reduce estimated discretization error in drag or pressure integral output functions. To enable application to high O(10(exp 7)) Reynolds number turbulent flows, a hybrid approach is utilized that freezes the near-wall boundary layer grids and adapts the grid away from the no slip boundaries. The hybrid approach is not applicable to problems with under resolved initial boundary layer grids, but is a powerful technique for problems with important off-body anisotropic features. Supersonic nozzle plume, turbulent flat plate, and shock-boundary layer interaction examples are presented with comparisons to experimental measurements of pressure and velocity. Adapted grids are produced that resolve off-body features in locations that are not known a priori.

  16. Ten adaptive strategies for family and work balance: advice from successful families.

    PubMed

    Haddock, S A; Zimmerman, T S; Ziemba, S J; Current, L R

    2001-10-01

    Despite negative media images and social dynamics insensitive to the lives of many dual-career couples, research shows that these families are largely healthy and thriving. In this study, we investigated the adaptive strategies of middle-class, dual-earner couples (N = 47) with children that are successfully managing family and work. Guided by grounded-theory methodology, analysis of interview data revealed that these successful couples structured their lives around 10 major strategies: Valuing family, striving for partnership, deriving meaning from work, maintaining work boundaries, focusing and producing at work, taking pride in dual earning, prioritizing family fun, living simply, making decisions proactively, and valuing time. Each adaptive strategy is defined and illustrated through the participants' own words. Clinical applications for therapists working with dual-earner couples are offered.

  17. Development of adaptation strategies of marshland water management to regional climate change

    NASA Astrophysics Data System (ADS)

    Bormann, Helge; Frank, Ahlhorn; Luise, Giani; Kirsten, Klaassen; Thomas, Klenke

    2010-05-01

    Since many centuries, low lying areas at the German North Sea coast are intensively managed by water boards and dike boards. Sophisticated water management systems have been developed in order to keep the water out of the low lying areas in wet periods, while in some regions additional water is needed in dry periods for agricultural and ecological purposes. For example in the Wesermarsch region, a water management system has been developed in historical times, draining the landscape in winter time by means of channels, ditches, gates, sluices and pumping stations. In contrast, in summer time water is conducted from Weser River into the Wesermarsch region to serve watering of animals, fencing grazing areas and ensuring a continuous flow in the marsh watercourses. Doing so, maintaining soil fertility is guaranteed for agriculture as well as protection against floods, sustaining river ecology and traditional livestock farming. Due to climate variability and river engineering, the water management of the Wesermarsch already runs into problems because watering in summer cannot be assured any longer in sufficient water quality. During high tides, salt water from the North Sea is flowing upstream into the Weser estuary, generating brackish conditions in the lower Weser River. In addition, soil subsidence and soil mineralization of marsh and peat soils as well as the sea level rise increase the necessary pumping frequency and the emerging energy costs. The expected future climate change will further aggravate those problems and require an adaptation of the current management system. This presentation introduces the concept behind and preliminary results of an integrative and participatory project, aiming at the development of a new water management strategy adapted to the regional climate change likely to occur until year 2050. In close cooperation with a number of regional stakeholders and based on the priorities with respect to the future development of the region

  18. Assessment of the effectiveness of participatory developed adaptation strategies for HCMC

    NASA Astrophysics Data System (ADS)

    Lasage, R.; Veldkamp, T. I. E.; de Moel, H.; Van, T. C.; Phi, H. L.; Vellinga, P.; Aerts, J. C. J. H.

    2014-01-01

    Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, especially Asian cities are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reducing measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea level rise and socio-economic developments on flood risk for the flood prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet flood proofing of buildings). A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. the model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in Expected Annual Damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea level scenarios and land use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5% and 5%. The results of this modeling study indicate that the current flood risk in District 4 is 0.31 million USD yr-1, increasing up to 0.78 million USD yr-1 in 2100. The net present value and benefit-cost ratios using a discount rate of 5% range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5% leads to an increase in both net present value and benefit cost ratio. The adaptation strategies wet proofing and dry proofing generate the best results using these economic indicators. The information on different strategies will be used by

  19. An adaptive P300-based control system

    NASA Astrophysics Data System (ADS)

    Jin, Jing; Allison, Brendan Z.; Sellers, Eric W.; Brunner, Clemens; Horki, Petar; Wang, Xingyu; Neuper, Christa

    2011-06-01

    An adaptive P300 brain-computer interface (BCI) using a 12 × 7 matrix explored new paradigms to improve bit rate and accuracy. During online use, the system adaptively selects the number of flashes to average. Five different flash patterns were tested. The 19-flash paradigm represents the typical row/column presentation (i.e. 12 columns and 7 rows). The 9- and 14-flash A and B paradigms present all items of the 12 × 7 matrix three times using either 9 or 14 flashes (instead of 19), decreasing the amount of time to present stimuli. Compared to 9-flash A, 9-flash B decreased the likelihood that neighboring items would flash when the target was not flashing, thereby reducing the interference from items adjacent to targets. 14-flash A also reduced the adjacent item interference and 14-flash B additionally eliminated successive (double) flashes of the same item. Results showed that the accuracy and bit rate of the adaptive system were higher than those of the non-adaptive system. In addition, 9- and 14-flash B produced significantly higher performance than their respective A conditions. The results also show the trend that the 14-flash B paradigm was better than the 19-flash pattern for naive users.

  20. Tandem carrying, a new foraging strategy in ants: description, function, and adaptive significance relative to other described foraging strategies

    NASA Astrophysics Data System (ADS)

    Guénard, Benoit; Silverman, Jules

    2011-08-01

    An important aspect of social insect biology lies in the expression of collective foraging strategies developed to exploit food. In ants, four main types of foraging strategies are typically recognized based on the intensity of recruitment and the importance of chemical communication. Here, we describe a new type of foraging strategy, "tandem carrying", which is also one of the most simple recruitment strategies, observed in the Ponerinae species Pachycondyla chinensis. Within this strategy, workers are directly carried individually and then released on the food resource by a successful scout. We demonstrate that this recruitment is context dependent and based on the type of food discovered and can be quickly adjusted as food quality changes. We did not detect trail marking by tandem-carrying workers. We conclude by discussing the importance of tandem carrying in an evolutionary context relative to other modes of recruitment in foraging and nest emigration.

  1. Socio-economic vulnerability of coastal communities in southern Thailand: the development of adaptation strategies

    NASA Astrophysics Data System (ADS)

    Willroth, P.; Massmann, F.; Wehrhahn, R.; Revilla Diez, J.

    2012-08-01

    The tsunami of December 2004 impacted large areas of Thailand's coastline and caused severe human and economic losses. The recovery period revealed differences in the vulnerabilities of communities affected. An understanding of the causal factors of vulnerability is crucial for minimising the negative effects of future threats and developing adaptive capacities. This paper analyses the vulnerabilities and the development of adaptation strategies in the booming tourist area of Khao Lak and in the predominantly fishing and agricultural area of Ban Nam Khem through a comprehensive vulnerability framework. The results show that social networks played a crucial role in coping with the disaster. Social cohesion is important for strengthening the community and developing successful adaptation strategies. The development of tourism and the turning away from traditional activities have a significant positive influence on the income situation, but create a dependency on a single business sector. It could be shown that households generating their income in the tourism sector were vulnerable unless they had diversified their income previously. Income diversification decreased the vulnerability in the study areas. Adaptation strategies and processes developed in the aftermath clearly address these issues.

  2. Use of the Metacognitive English Language Learning Strategies Based on Personality Traits

    ERIC Educational Resources Information Center

    Fazeli, Seyed Hossein

    2012-01-01

    The present study aims to find out the relationship between use of the Metacognitive English Language Learning Strategies (MELLSs) for learners of English as a foreign language based on personality traits, and the role of personality traits in the prediction of use of such Strategies. Four instruments were used, which were Adapted Inventory for…

  3. Social and natural sciences differ in their research strategies, adapted to work for different knowledge landscapes.

    PubMed

    Jaffe, Klaus

    2014-01-01

    Do different fields of knowledge require different research strategies? A numerical model exploring different virtual knowledge landscapes, revealed two diverging optimal search strategies. Trend following is maximized when the popularity of new discoveries determine the number of individuals researching it. This strategy works best when many researchers explore few large areas of knowledge. In contrast, individuals or small groups of researchers are better in discovering small bits of information in dispersed knowledge landscapes. Bibliometric data of scientific publications showed a continuous bipolar distribution of these strategies, ranging from natural sciences, with highly cited publications in journals containing a large number of articles, to the social sciences, with rarely cited publications in many journals containing a small number of articles. The natural sciences seem to adapt their research strategies to landscapes with large concentrated knowledge clusters, whereas social sciences seem to have adapted to search in landscapes with many small isolated knowledge clusters. Similar bipolar distributions were obtained when comparing levels of insularity estimated by indicators of international collaboration and levels of country-self citations: researchers in academic areas with many journals such as social sciences, arts and humanities, were the most isolated, and that was true in different regions of the world. The work shows that quantitative measures estimating differences between academic disciplines improve our understanding of different research strategies, eventually helping interdisciplinary research and may be also help improve science policies worldwide.

  4. Social and Natural Sciences Differ in Their Research Strategies, Adapted to Work for Different Knowledge Landscapes

    PubMed Central

    Jaffe, Klaus

    2014-01-01

    Do different fields of knowledge require different research strategies? A numerical model exploring different virtual knowledge landscapes, revealed two diverging optimal search strategies. Trend following is maximized when the popularity of new discoveries determine the number of individuals researching it. This strategy works best when many researchers explore few large areas of knowledge. In contrast, individuals or small groups of researchers are better in discovering small bits of information in dispersed knowledge landscapes. Bibliometric data of scientific publications showed a continuous bipolar distribution of these strategies, ranging from natural sciences, with highly cited publications in journals containing a large number of articles, to the social sciences, with rarely cited publications in many journals containing a small number of articles. The natural sciences seem to adapt their research strategies to landscapes with large concentrated knowledge clusters, whereas social sciences seem to have adapted to search in landscapes with many small isolated knowledge clusters. Similar bipolar distributions were obtained when comparing levels of insularity estimated by indicators of international collaboration and levels of country-self citations: researchers in academic areas with many journals such as social sciences, arts and humanities, were the most isolated, and that was true in different regions of the world. The work shows that quantitative measures estimating differences between academic disciplines improve our understanding of different research strategies, eventually helping interdisciplinary research and may be also help improve science policies worldwide. PMID:25426723

  5. Adaptive terminal sliding-mode control strategy for DC-DC buck converters.

    PubMed

    Komurcugil, Hasan

    2012-11-01

    This paper presents an adaptive terminal sliding mode control (ATSMC) strategy for DC-DC buck converters. The idea behind this strategy is to use the terminal sliding mode control (TSMC) approach to assure finite time convergence of the output voltage error to the equilibrium point and integrate an adaptive law to the TSMC strategy so as to achieve a dynamic sliding line during the load variations. In addition, the influence of the controller parameters on the performance of closed-loop system is investigated. It is observed that the start up response of the output voltage becomes faster with increasing value of the fractional power used in the sliding function. On the other hand, the transient response of the output voltage, caused by the step change in the load, becomes faster with decreasing the value of the fractional power. Therefore, the value of fractional power is to be chosen to make a compromise between start up and transient responses of the converter. Performance of the proposed ATSMC strategy has been tested through computer simulations and experiments. The simulation results of the proposed ATSMC strategy are compared with the conventional SMC and TSMC strategies. It is shown that the ATSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes.

  6. Cautious but committed: moving toward adaptive planning and operation strategies for renewable energy's wildlife implications.

    PubMed

    Köppel, Johann; Dahmen, Marie; Helfrich, Jennifer; Schuster, Eva; Bulling, Lea

    2014-10-01

    Wildlife planning for renewable energy must cope with the uncertainties of potential wildlife impacts. Unfortunately, the environmental policies which instigate renewable energy and those which protect wildlife are not coherently aligned-creating a green versus green dilemma. Thus, climate mitigation efforts trigger renewable energy development, but then face substantial barriers from biodiversity protection instruments and practices. This article briefly reviews wind energy and wildlife interactions, highlighting the lively debated effects on bats. Today, planning and siting of renewable energy are guided by the precautionary principle in an attempt to carefully address wildlife challenges. However, this planning attitude creates limitations as it struggles to negotiate the aforementioned green versus green dilemma. More adaptive planning and management strategies and practices hold the potential to reconcile these discrepancies to some degree. This adaptive approach is discussed using facets of case studies from policy, planning, siting, and operational stages of wind energy in Germany and the United States, with one case showing adaptive planning in action for solar energy as well. This article attempts to highlight the benefits of more adaptive approaches as well as the possible shortcomings, such as reduced planning security for renewable energy developers. In conclusion, these studies show that adaptive planning and operation strategies can be designed to supplement and enhance the precautionary principle in wildlife planning for green energy. PMID:25096164

  7. Cautious but committed: moving toward adaptive planning and operation strategies for renewable energy's wildlife implications.

    PubMed

    Köppel, Johann; Dahmen, Marie; Helfrich, Jennifer; Schuster, Eva; Bulling, Lea

    2014-10-01

    Wildlife planning for renewable energy must cope with the uncertainties of potential wildlife impacts. Unfortunately, the environmental policies which instigate renewable energy and those which protect wildlife are not coherently aligned-creating a green versus green dilemma. Thus, climate mitigation efforts trigger renewable energy development, but then face substantial barriers from biodiversity protection instruments and practices. This article briefly reviews wind energy and wildlife interactions, highlighting the lively debated effects on bats. Today, planning and siting of renewable energy are guided by the precautionary principle in an attempt to carefully address wildlife challenges. However, this planning attitude creates limitations as it struggles to negotiate the aforementioned green versus green dilemma. More adaptive planning and management strategies and practices hold the potential to reconcile these discrepancies to some degree. This adaptive approach is discussed using facets of case studies from policy, planning, siting, and operational stages of wind energy in Germany and the United States, with one case showing adaptive planning in action for solar energy as well. This article attempts to highlight the benefits of more adaptive approaches as well as the possible shortcomings, such as reduced planning security for renewable energy developers. In conclusion, these studies show that adaptive planning and operation strategies can be designed to supplement and enhance the precautionary principle in wildlife planning for green energy.

  8. Domain-based Teaching Strategy for Intelligent Tutoring System Based on Generic Rules

    NASA Astrophysics Data System (ADS)

    Kseibat, Dawod; Mansour, Ali; Adjei, Osei; Phillips, Paul

    In this paper we present a framework for selecting the proper instructional strategy for a given teaching material based on its attributes. The new approach is based on a flexible design by means of generic rules. The framework was adapted in an Intelligent Tutoring System to teach Modern Standard Arabic language to adult English-speaking learners with no pre-knowledge of Arabic language is required.

  9. Managing for Climate Change in Western Forest Ecosystems; The Role of Refugia in Adaptation Strategies (Invited)

    NASA Astrophysics Data System (ADS)

    Millar, C. I.; Morelli, T.

    2009-12-01

    Managing forested ecosystems in western North America for adaptation to climate change involves options that depend on resource objectives, landscape conditions, sensitivity to change, and social desires. Strategies range from preserving species and ecosystems in the face of change (resisting change); managing for resilience to change; realigning ecosystems that have been severely altered so that they can adapt successfully; and enabling species to respond to climate changes. We are exploring one extreme in this range of strategies, that is, to manage locations, species, communities, or ecosystems as refugia. This concept is familiar from the Quaternary literature as isolated locations where climates remained warm during cold glacial intervals and wherein species contracted and persisted in small populations. References to refugia have been made in the climate-adaptation literature but little elaborated, and applications have not been described. We are addressing this gap conceptually and in case-studies from national forest and national park environments in California. Using a classification of refugium categories, we extend the concept beyond the original use to include diverse locations and conditions where plant or animal species, or ecosystems of concern, would persist during future changing climatic backgrounds. These locations may be determined as refugial for reasons of local microclimate, substrate, elevation, topographic context, paleohistory, species ecology, or management capacity. Recognizing that species and ecosystems respond to climate change differently, refugium strategies are appropriate in some situations and not others. We describe favorable conditions for using refugium strategies and elaborate specific approaches in Sierra Nevada case studies.

  10. Adaptive control based on retrospective cost optimization

    NASA Technical Reports Server (NTRS)

    Santillo, Mario A. (Inventor); Bernstein, Dennis S. (Inventor)

    2012-01-01

    A discrete-time adaptive control law for stabilization, command following, and disturbance rejection that is effective for systems that are unstable, MIMO, and/or nonminimum phase. The adaptive control algorithm includes guidelines concerning the modeling information needed for implementation. This information includes the relative degree, the first nonzero Markov parameter, and the nonminimum-phase zeros. Except when the plant has nonminimum-phase zeros whose absolute value is less than the plant's spectral radius, the required zero information can be approximated by a sufficient number of Markov parameters. No additional information about the poles or zeros need be known. Numerical examples are presented to illustrate the algorithm's effectiveness in handling systems with errors in the required modeling data, unknown latency, sensor noise, and saturation.

  11. Adaptive skin detection based on online training

    NASA Astrophysics Data System (ADS)

    Zhang, Ming; Tang, Liang; Zhou, Jie; Rong, Gang

    2007-11-01

    Skin is a widely used cue for porn image classification. Most conventional methods are off-line training schemes. They usually use a fixed boundary to segment skin regions in the images and are effective only in restricted conditions: e.g. good lightness and unique human race. This paper presents an adaptive online training scheme for skin detection which can handle these tough cases. In our approach, skin detection is considered as a classification problem on Gaussian mixture model. For each image, human face is detected and the face color is used to establish a primary estimation of skin color distribution. Then an adaptive online training algorithm is used to find the real boundary between skin color and background color in current image. Experimental results on 450 images showed that the proposed method is more robust in general situations than the conventional ones.

  12. Image Watermarking Based on Adaptive Models of Human Visual Perception

    NASA Astrophysics Data System (ADS)

    Khawne, Amnach; Hamamoto, Kazuhiko; Chitsobhuk, Orachat

    This paper proposes a digital image watermarking based on adaptive models of human visual perception. The algorithm exploits the local activities estimated from wavelet coefficients of each subband to adaptively control the luminance masking. The adaptive luminance is thus delicately combined with the contrast masking and edge detection and adopted as a visibility threshold. With the proposed combination of adaptive visual sensitivity parameters, the proposed perceptual model can be more appropriate to the different characteristics of various images. The weighting function is chosen such that the fidelity, imperceptibility and robustness could be preserved without making any perceptual difference to the image quality.

  13. Nutritional strategies to support adaptation to high-intensity interval training in team sports.

    PubMed

    Gibala, Martin J

    2013-01-01

    Team sports are characterized by intermittent high-intensity activity patterns. Typically, play consists of short periods of very intense or all-out efforts interspersed with longer periods of low-intensity activity. Fatigue is a complex, multi-factorial process, but intense intermittent exercise performance can potentially be limited by reduced availability of substrates stored in skeletal muscle and/or metabolic by-products associated with fuel breakdown. High-intensity interval training (HIT) has been shown to induce adaptations in skeletal muscle that enhance the capacity for both oxidative and non-oxidative metabolism. Nutrient availability is a potent modulator of many acute physiological responses to exercise, including various molecular signaling pathways that are believed to regulate cellular adaptation to training. Several nutritional strategies have also been reported to acutely alter metabolism and enhance intermittent high-intensity exercise performance. However, relatively little is known regarding the effect of chronic interventions, and whether supplementation over a period of weeks or months augments HIT-induced physiological remodeling and promotes greater performance adaptations. Theoretically, a nutritional intervention could augment HIT adaptation by improving energy metabolism during exercise, which could facilitate greater total work and an enhanced chronic training stimulus, or promoting some aspect of the adaptive response during recovery, which could lead to enhanced physiological adaptations over time.

  14. Adaptation Strategies to Climate Change and the Role of Planning Instruments - The Example of the Dresden Region (Saxony/Germany)

    NASA Astrophysics Data System (ADS)

    Albrecht, J.; Juta, K.; Nobis, A.

    2009-04-01

    In the past, identifying anthropogenic influences on climate change, scenario analyses and issues of climate change mitigation were predominant approaches in climate change research (IPCC 2007). Currently, for instance in Germany, climate impact research on regional level comes to the forefront of research and policy making. Climate change has become an important topic on the agenda of politicians, administration and planning. In order to counteract the (unavoidable) climate change and its impacts it is necessary to develop adaptation strategies. At present, such strategies and guidelines are formulated on international, supranational and national level. The initial point was the United Nations Framework Convention on Climate Change in 1992 where the contracting states obligated themselves to develop national (and regional) programmes for adaptation. In 2007 the European Commission published its Green Paper called Adaptation to Climate Change in Europe. The paper states that adaptation efforts have to be intensified at different (spatial) levels (local, regional, national, and so forth). Furthermore, coordinating these efforts is of high importance. With the recent agreement on the German Adaptation Strategy to Climate Change (DAS 2008) in December 2008, federal government tries to accomplish this task. The German strategy mainly focuses on two elements: decreasing vulnerability and increasing adaptability. While the above mentioned strategies have presented information and policies concerning climate change and adaptation on international, supranational and national level, such documents dońt yet exist on regional level. However, because of their close link to the local level the regions are of high importance for adaptation strategies. Therefore, the Leibniz-Institute of Ecological and Regional Development developed a transdisciplinary project to formulate and implement the so-called Integrated Regional Climate Adaptation Programme (IRCAP) for the Model Region

  15. Effects of climate change on rice production and strategies for adaptation in southern China

    SciTech Connect

    Jin, Z.; Ge, D.; Chen, H.; Fang, J.

    1995-12-31

    The CERES-rice (Oryza sativa L.) model was calibrated and validated for nine sites in southern China to examine its suitability to model rice production in this area, using agronomic data from more than three successive years. After determining the genetic coefficients for the cultivars, the CERES-rice model was run a second time for the same locations for a time period of 20 to 30 yr. The model used local climate data (1958--1986) and doubled-CO{sub 2} climate change scenarios generated from the Goddard Institute for Space Studies (GISS), Geophysical Fluid dynamics Laboratory (GFDL), and United Kingdom Meteorological Office (UKMO) global climate models (GCMs), with and without supplemental irrigation(to model paddy and upland rice, respectively). The study estimated the potential impacts of climate change on rice production by comparing the base runs with the runs under the three doubled-CO{sub 2} GCM scenarios and it considered the physiological effects of CO{sub 2} on rice growth in each GCM scenario. Finally, the study examined several strategies for adapting to climate change.

  16. Design and Analysis of Self-Adapted Task Scheduling Strategies in Wireless Sensor Networks

    PubMed Central

    Guo, Wenzhong; Xiong, Naixue; Chao, Han-Chieh; Hussain, Sajid; Chen, Guolong

    2011-01-01

    In a wireless sensor network (WSN), the usage of resources is usually highly related to the execution of tasks which consume a certain amount of computing and communication bandwidth. Parallel processing among sensors is a promising solution to provide the demanded computation capacity in WSNs. Task allocation and scheduling is a typical problem in the area of high performance computing. Although task allocation and scheduling in wired processor networks has been well studied in the past, their counterparts for WSNs remain largely unexplored. Existing traditional high performance computing solutions cannot be directly implemented in WSNs due to the limitations of WSNs such as limited resource availability and the shared communication medium. In this paper, a self-adapted task scheduling strategy for WSNs is presented. First, a multi-agent-based architecture for WSNs is proposed and a mathematical model of dynamic alliance is constructed for the task allocation problem. Then an effective discrete particle swarm optimization (PSO) algorithm for the dynamic alliance (DPSO-DA) with a well-designed particle position code and fitness function is proposed. A mutation operator which can effectively improve the algorithm’s ability of global search and population diversity is also introduced in this algorithm. Finally, the simulation results show that the proposed solution can achieve significant better performance than other algorithms. PMID:22163971

  17. An adaptable peptide-based porous material.

    PubMed

    Rabone, J; Yue, Y-F; Chong, S Y; Stylianou, K C; Bacsa, J; Bradshaw, D; Darling, G R; Berry, N G; Khimyak, Y Z; Ganin, A Y; Wiper, P; Claridge, J B; Rosseinsky, M J

    2010-08-27

    Porous materials find widespread application in storage, separation, and catalytic technologies. We report a crystalline porous solid with adaptable porosity, in which a simple dipeptide linker is arranged in a regular array by coordination to metal centers. Experiments reinforced by molecular dynamics simulations showed that low-energy torsions and displacements of the peptides enabled the available pore volume to evolve smoothly from zero as the guest loading increased. The observed cooperative feedback in sorption isotherms resembled the response of proteins undergoing conformational selection, suggesting an energy landscape similar to that required for protein folding. The flexible peptide linker was shown to play the pivotal role in changing the pore conformation.

  18. Lens based adaptive optics scanning laser ophthalmoscope.

    PubMed

    Felberer, Franz; Kroisamer, Julia-Sophie; Hitzenberger, Christoph K; Pircher, Michael

    2012-07-30

    We present an alternative approach for an adaptive optics scanning laser ophthalmoscope (AO-SLO). In contrast to other commonly used AO-SLO instruments, the imaging optics consist of lenses. Images of the fovea region of 5 healthy volunteers are recorded. The system is capable to resolve human foveal cones in 3 out of 5 healthy volunteers. Additionally, we investigated the capability of the system to support larger scanning angles (up to 5°) on the retina. Finally, in order to demonstrate the performance of the instrument images of rod photoreceptors are presented.

  19. An Adaptive Mesh Refinement Strategy for Immersed Boundary/Interface Methods.

    PubMed

    Li, Zhilin; Song, Peng

    2012-01-01

    An adaptive mesh refinement strategy is proposed in this paper for the Immersed Boundary and Immersed Interface methods for two-dimensional elliptic interface problems involving singular sources. The interface is represented by the zero level set of a Lipschitz function φ(x,y). Our adaptive mesh refinement is done within a small tube of |φ(x,y)|≤ δ with finer Cartesian meshes. The discrete linear system of equations is solved by a multigrid solver. The AMR methods could obtain solutions with accuracy that is similar to those on a uniform fine grid by distributing the mesh more economically, therefore, reduce the size of the linear system of the equations. Numerical examples presented show the efficiency of the grid refinement strategy.

  20. An Adaptive Mesh Refinement Strategy for Immersed Boundary/Interface Methods

    PubMed Central

    Li, Zhilin; Song, Peng

    2012-01-01

    An adaptive mesh refinement strategy is proposed in this paper for the Immersed Boundary and Immersed Interface methods for two-dimensional elliptic interface problems involving singular sources. The interface is represented by the zero level set of a Lipschitz function φ(x,y). Our adaptive mesh refinement is done within a small tube of |φ(x,y)|≤ δ with finer Cartesian meshes. The discrete linear system of equations is solved by a multigrid solver. The AMR methods could obtain solutions with accuracy that is similar to those on a uniform fine grid by distributing the mesh more economically, therefore, reduce the size of the linear system of the equations. Numerical examples presented show the efficiency of the grid refinement strategy. PMID:22670155

  1. Workload Model Based Dynamic Adaptation of Social Internet of Vehicles

    PubMed Central

    Alam, Kazi Masudul; Saini, Mukesh; El Saddik, Abdulmotaleb

    2015-01-01

    Social Internet of Things (SIoT) has gained much interest among different research groups in recent times. As a key member of a smart city, the vehicular domain of SIoT (SIoV) is also undergoing steep development. In the SIoV, vehicles work as sensor-hub to capture surrounding information using the in-vehicle and Smartphone sensors and later publish them for the consumers. A cloud centric cyber-physical system better describes the SIoV model where physical sensing-actuation process affects the cloud based service sharing or computation in a feedback loop or vice versa. The cyber based social relationship abstraction enables distributed, easily navigable and scalable peer-to-peer communication among the SIoV subsystems. These cyber-physical interactions involve a huge amount of data and it is difficult to form a real instance of the system to test the feasibility of SIoV applications. In this paper, we propose an analytical model to measure the workloads of various subsystems involved in the SIoV process. We present the basic model which is further extended to incorporate complex scenarios. We provide extensive simulation results for different parameter settings of the SIoV system. The findings of the analyses are further used to design example adaptation strategies for the SIoV subsystems which would foster deployment of intelligent transport systems. PMID:26389905

  2. Workload Model Based Dynamic Adaptation of Social Internet of Vehicles.

    PubMed

    Alam, Kazi Masudul; Saini, Mukesh; El Saddik, Abdulmotaleb

    2015-09-15

    Social Internet of Things (SIoT) has gained much interest among different research groups in recent times. As a key member of a smart city, the vehicular domain of SIoT (SIoV) is also undergoing steep development. In the SIoV, vehicles work as sensor-hub to capture surrounding information using the in-vehicle and Smartphone sensors and later publish them for the consumers. A cloud centric cyber-physical system better describes the SIoV model where physical sensing-actuation process affects the cloud based service sharing or computation in a feedback loop or vice versa. The cyber based social relationship abstraction enables distributed, easily navigable and scalable peer-to-peer communication among the SIoV subsystems. These cyber-physical interactions involve a huge amount of data and it is difficult to form a real instance of the system to test the feasibility of SIoV applications. In this paper, we propose an analytical model to measure the workloads of various subsystems involved in the SIoV process. We present the basic model which is further extended to incorporate complex scenarios. We provide extensive simulation results for different parameter settings of the SIoV system. The findings of the analyses are further used to design example adaptation strategies for the SIoV subsystems which would foster deployment of intelligent transport systems.

  3. Workload Model Based Dynamic Adaptation of Social Internet of Vehicles.

    PubMed

    Alam, Kazi Masudul; Saini, Mukesh; El Saddik, Abdulmotaleb

    2015-01-01

    Social Internet of Things (SIoT) has gained much interest among different research groups in recent times. As a key member of a smart city, the vehicular domain of SIoT (SIoV) is also undergoing steep development. In the SIoV, vehicles work as sensor-hub to capture surrounding information using the in-vehicle and Smartphone sensors and later publish them for the consumers. A cloud centric cyber-physical system better describes the SIoV model where physical sensing-actuation process affects the cloud based service sharing or computation in a feedback loop or vice versa. The cyber based social relationship abstraction enables distributed, easily navigable and scalable peer-to-peer communication among the SIoV subsystems. These cyber-physical interactions involve a huge amount of data and it is difficult to form a real instance of the system to test the feasibility of SIoV applications. In this paper, we propose an analytical model to measure the workloads of various subsystems involved in the SIoV process. We present the basic model which is further extended to incorporate complex scenarios. We provide extensive simulation results for different parameter settings of the SIoV system. The findings of the analyses are further used to design example adaptation strategies for the SIoV subsystems which would foster deployment of intelligent transport systems. PMID:26389905

  4. Kalman filter based control for Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Petit, Cyril; Quiros-Pacheco, Fernando; Conan, Jean-Marc; Kulcsár, Caroline; Raynaud, Henri-François; Fusco, Thierry

    2004-12-01

    Classical Adaptive Optics suffer from a limitation of the corrected Field Of View. This drawback has lead to the development of MultiConjugated Adaptive Optics. While the first MCAO experimental set-ups are presently under construction, little attention has been paid to the control loop. This is however a key element in the optimization process especially for MCAO systems. Different approaches have been proposed in recent articles for astronomical applications : simple integrator, Optimized Modal Gain Integrator and Kalman filtering. We study here Kalman filtering which seems a very promising solution. Following the work of Brice Leroux, we focus on a frequential characterization of kalman filters, computing a transfer matrix. The result brings much information about their behaviour and allows comparisons with classical controllers. It also appears that straightforward improvements of the system models can lead to static aberrations and vibrations filtering. Simulation results are proposed and analysed thanks to our frequential characterization. Related problems such as model errors, aliasing effect reduction or experimental implementation and testing of Kalman filter control loop on a simplified MCAO experimental set-up could be then discussed.

  5. Modular adaptive implant based on smart materials.

    PubMed

    Bîzdoacă, N; Tarniţă, Daniela; Tarniţă, D N

    2008-01-01

    Applications of biological methods and systems found in nature to the study and design of engineering systems and modern technology are defined as Bionics. The present paper describes a bionics application of shape memory alloy in construction of orthopedic implant. The main idea of this paper is related to design modular adaptive implants for fractured bones. In order to target the efficiency of medical treatment, the implant has to protect the fractured bone, for the healing period, undertaking much as is possible from the daily usual load of the healthy bones. After a particular stage of healing period is passed, using implant modularity, the load is gradually transferred to bone, assuring in this manner a gradually recover of bone function. The adaptability of this design is related to medical possibility of the physician to made the implant to correspond to patient specifically anatomy. Using a CT realistic numerical bone models, the mechanical simulation of different types of loading of the fractured bones treated with conventional method are presented. The results are commented and conclusions are formulated. PMID:19050799

  6. Invasion strategies in clonal aquatic plants: are phenotypic differences caused by phenotypic plasticity or local adaptation?

    PubMed Central

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit; Clayton, John S.; Brix, Hans; Sorrell, Brian K.

    2010-01-01

    Background and Aims The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important. Here the primary adaptive strategy in three non-native, clonally reproducing macrophytes (Egeria densa, Elodea canadensis and Lagarosiphon major) in New Zealand freshwaters were examined and an attempt was made to link observed differences in plant morphology to local variation in habitat conditions. Methods Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity of these same populations was also quantified. Key Results For all three species, greater variation in plant characteristics was found before they were grown in standardized conditions. Moreover, field populations displayed remarkably little genetic variation and there was little interaction between habitat conditions and plant morphological characteristics. Conclusions The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis and L. major, but no other relationships between plant characteristics and habitat conditions were apparent. This implies that within-species differences in plant size can be explained

  7. Shifted encoding strategy in retinal luminance adaptation: from firing rate to neural correlation.

    PubMed

    Xiao, Lei; Zhang, Mingsha; Xing, Dajun; Liang, Pei-Ji; Wu, Si

    2013-10-01

    Neuronal responses to prolonged stimulation attenuate over time. Here, we ask a fundamental question: is adaptation a simple process for the neural system during which sustained input is ignored, or is it actually part of a strategy for the neural system to adjust its encoding properties dynamically? After simultaneously recording the activities of a group of bullfrog's retinal ganglion cells (dimming detectors) in response to sustained dimming stimulation, we applied a combination of information analysis approaches to explore the time-dependent nature of information encoding during the adaptation. We found that at the early stage of the adaptation, the stimulus information was mainly encoded in firing rates, whereas at the late stage of the adaptation, it was more encoded in neural correlations. Such a transition in encoding properties is not a simple consequence of the attenuation of neuronal firing rates, but rather involves an active change in the neural correlation strengths, suggesting that it is a strategy adopted by the neural system for functional purposes. Our results reveal that in encoding a prolonged stimulation, the neural system may utilize concerted, but less active, firings of neurons to encode information.

  8. Can Impacts of Climate Change and Agricultural Adaptation Strategies Be Accurately Quantified if Crop Models Are Annually Re-Initialized?

    PubMed Central

    Basso, Bruno; Hyndman, David W.; Kendall, Anthony D.; Grace, Peter R.; Robertson, G. Philip

    2015-01-01

    Estimates of climate change impacts on global food production are generally based on statistical or process-based models. Process-based models can provide robust predictions of agricultural yield responses to changing climate and management. However, applications of these models often suffer from bias due to the common practice of re-initializing soil conditions to the same state for each year of the forecast period. If simulations neglect to include year-to-year changes in initial soil conditions and water content related to agronomic management, adaptation and mitigation strategies designed to maintain stable yields under climate change cannot be properly evaluated. We apply a process-based crop system model that avoids re-initialization bias to demonstrate the importance of simulating both year-to-year and cumulative changes in pre-season soil carbon, nutrient, and water availability. Results are contrasted with simulations using annual re-initialization, and differences are striking. We then demonstrate the potential for the most likely adaptation strategy to offset climate change impacts on yields using continuous simulations through the end of the 21st century. Simulations that annually re-initialize pre-season soil carbon and water contents introduce an inappropriate yield bias that obscures the potential for agricultural management to ameliorate the deleterious effects of rising temperatures and greater rainfall variability. PMID:26043188

  9. Can Impacts of Climate Change and Agricultural Adaptation Strategies Be Accurately Quantified if Crop Models Are Annually Re-Initialized?

    PubMed

    Basso, Bruno; Hyndman, David W; Kendall, Anthony D; Grace, Peter R; Robertson, G Philip

    2015-01-01

    Estimates of climate change impacts on global food production are generally based on statistical or process-based models. Process-based models can provide robust predictions of agricultural yield responses to changing climate and management. However, applications of these models often suffer from bias due to the common practice of re-initializing soil conditions to the same state for each year of the forecast period. If simulations neglect to include year-to-year changes in initial soil conditions and water content related to agronomic management, adaptation and mitigation strategies designed to maintain stable yields under climate change cannot be properly evaluated. We apply a process-based crop system model that avoids re-initialization bias to demonstrate the importance of simulating both year-to-year and cumulative changes in pre-season soil carbon, nutrient, and water availability. Results are contrasted with simulations using annual re-initialization, and differences are striking. We then demonstrate the potential for the most likely adaptation strategy to offset climate change impacts on yields using continuous simulations through the end of the 21st century. Simulations that annually re-initialize pre-season soil carbon and water contents introduce an inappropriate yield bias that obscures the potential for agricultural management to ameliorate the deleterious effects of rising temperatures and greater rainfall variability.

  10. Testing Strategies for Model-Based Development

    NASA Technical Reports Server (NTRS)

    Heimdahl, Mats P. E.; Whalen, Mike; Rajan, Ajitha; Miller, Steven P.

    2006-01-01

    This report presents an approach for testing artifacts generated in a model-based development process. This approach divides the traditional testing process into two parts: requirements-based testing (validation testing) which determines whether the model implements the high-level requirements and model-based testing (conformance testing) which determines whether the code generated from a model is behaviorally equivalent to the model. The goals of the two processes differ significantly and this report explores suitable testing metrics and automation strategies for each. To support requirements-based testing, we define novel objective requirements coverage metrics similar to existing specification and code coverage metrics. For model-based testing, we briefly describe automation strategies and examine the fault-finding capability of different structural coverage metrics using tests automatically generated from the model.

  11. Farmers' Perceptions of Climate Change and Agricultural Adaptation Strategies in Rural Sahel

    NASA Astrophysics Data System (ADS)

    Mertz, Ole; Mbow, Cheikh; Reenberg, Anette; Diouf, Awa

    2009-05-01

    Farmers in the Sahel have always been facing climatic variability at intra- and inter-annual and decadal time scales. While coping and adaptation strategies have traditionally included crop diversification, mobility, livelihood diversification, and migration, singling out climate as a direct driver of changes is not so simple. Using focus group interviews and a household survey, this study analyzes the perceptions of climate change and the strategies for coping and adaptation by sedentary farmers in the savanna zone of central Senegal. Households are aware of climate variability and identify wind and occasional excess rainfall as the most destructive climate factors. Households attribute poor livestock health, reduced crop yields and a range of other problems to climate factors, especially wind. However, when questions on land use and livelihood change are not asked directly in a climate context, households and groups assign economic, political, and social rather than climate factors as the main reasons for change. It is concluded that the communities studied have a high awareness of climate issues, but climatic narratives are likely to influence responses when questions mention climate. Change in land use and livelihood strategies is driven by adaptation to a range of factors of which climate appears not to be the most important. Implications for policy-making on agricultural and economic development will be to focus on providing flexible options rather than specific solutions to uncertain climate.

  12. Farmers' perceptions of climate change and agricultural adaptation strategies in rural Sahel.

    PubMed

    Mertz, Ole; Mbow, Cheikh; Reenberg, Anette; Diouf, Awa

    2009-05-01

    Farmers in the Sahel have always been facing climatic variability at intra- and inter-annual and decadal time scales. While coping and adaptation strategies have traditionally included crop diversification, mobility, livelihood diversification, and migration, singling out climate as a direct driver of changes is not so simple. Using focus group interviews and a household survey, this study analyzes the perceptions of climate change and the strategies for coping and adaptation by sedentary farmers in the savanna zone of central Senegal. Households are aware of climate variability and identify wind and occasional excess rainfall as the most destructive climate factors. Households attribute poor livestock health, reduced crop yields and a range of other problems to climate factors, especially wind. However, when questions on land use and livelihood change are not asked directly in a climate context, households and groups assign economic, political, and social rather than climate factors as the main reasons for change. It is concluded that the communities studied have a high awareness of climate issues, but climatic narratives are likely to influence responses when questions mention climate. Change in land use and livelihood strategies is driven by adaptation to a range of factors of which climate appears not to be the most important. Implications for policy-making on agricultural and economic development will be to focus on providing flexible options rather than specific solutions to uncertain climate. PMID:18810526

  13. Farmers' perceptions of climate change and agricultural adaptation strategies in rural Sahel.

    PubMed

    Mertz, Ole; Mbow, Cheikh; Reenberg, Anette; Diouf, Awa

    2009-05-01

    Farmers in the Sahel have always been facing climatic variability at intra- and inter-annual and decadal time scales. While coping and adaptation strategies have traditionally included crop diversification, mobility, livelihood diversification, and migration, singling out climate as a direct driver of changes is not so simple. Using focus group interviews and a household survey, this study analyzes the perceptions of climate change and the strategies for coping and adaptation by sedentary farmers in the savanna zone of central Senegal. Households are aware of climate variability and identify wind and occasional excess rainfall as the most destructive climate factors. Households attribute poor livestock health, reduced crop yields and a range of other problems to climate factors, especially wind. However, when questions on land use and livelihood change are not asked directly in a climate context, households and groups assign economic, political, and social rather than climate factors as the main reasons for change. It is concluded that the communities studied have a high awareness of climate issues, but climatic narratives are likely to influence responses when questions mention climate. Change in land use and livelihood strategies is driven by adaptation to a range of factors of which climate appears not to be the most important. Implications for policy-making on agricultural and economic development will be to focus on providing flexible options rather than specific solutions to uncertain climate.

  14. DEVS-based intelligent control of space adapted fluid mixing

    NASA Technical Reports Server (NTRS)

    Chi, Sung-Do; Zeigler, Bernard P.

    1990-01-01

    The development is described of event-based intelligent control system for a space-adapted mixing process by employing the DEVS (Discrete Event System Specification) formalism. In this control paradigm, the controller expects to receive confirming sensor responses to its control commands within definite time windows determined by its DEVS model of the system under control. The DEVS-based intelligent control paradigm was applied in a space-adapted mixing system capable of supporting the laboratory automation aboard a Space Station.

  15. Assessment of impact of climate change and adaptation strategies on maize production in Uganda

    NASA Astrophysics Data System (ADS)

    Kikoyo, Duncan A.; Nobert, Joel

    2016-06-01

    Globally, various climatic studies have estimated a reduction of crop yields due to changes in surface temperature and precipitation especially for the developing countries which is heavily dependent on agriculture and lacks resources to counter the negative effects of climate change. Uganda's economy and the wellbeing of its populace depend on rain-fed agriculture which is susceptible to climate change. This study quantified the impacts of climate change and variability in Uganda and how coping strategies can enhance crop production against climate change and/or variability. The study used statistical methods to establish various climate change and variability indicators across the country, and uses the FAO AquaCrop model to simulate yields under possible future climate scenarios with and without adaptation strategies. Maize, the most widely grown crop was used for the study. Meteorological, soil and crop data were collected for various districts representing the maize growing ecological zones in the country. Based on this study, it was found that temperatures have increased by up to 1 °C across much of Uganda since the 1970s, with rates of warming around 0.3 °C per decade across the country. High altitude, low rainfall regions experience the highest level of warming, with over 0.5 °C/decade recorded in Kasese. Rainfall is variable and does not follow a specific significant increasing or decreasing trend. For both future climate scenarios, Maize yields will reduce in excess of 4.7% for the fast warming-low rainfall climates but increase on average by 3.5% for slow warming-high rainfall regions, by 2050. Improved soil fertility can improve yields by over 50% while mulching and use of surface water management practices improve yields by single digit percentages. The use of fertilizer application needs to go hand in hand with other water management strategies since more yields as a result of the improved soil fertility leads to increased water stress, especially

  16. The Conceptual Bases of Study Strategy Inventories

    ERIC Educational Resources Information Center

    Entwistle, Noel; McCune, Velda

    2004-01-01

    This article describes the historical origins and development of a series of well-known study strategy inventories and seeks to identify their conceptual bases. The theories and evidence influencing the development of 6 contrasting instruments are considered before examining empirical evidence of similarities and differences between the…

  17. Competency-Based Human Resource Development Strategy

    ERIC Educational Resources Information Center

    Gangani, Noordeen T.; McLean, Gary N.; Braden, Richard A.

    2004-01-01

    This paper explores issues in developing and implementing a competency-based human resource development strategy. The paper summarizes a literature review on how competency models can improve HR performance. A case study is presented of American Medical Systems (AMS), a mid-sized health-care and medical device company, where the model is being…

  18. Climate change and eHealth: a promising strategy for health sector mitigation and adaptation.

    PubMed

    Holmner, Asa; Rocklöv, Joacim; Ng, Nawi; Nilsson, Maria

    2012-01-01

    Climate change is one of today's most pressing global issues. Policies to guide mitigation and adaptation are needed to avoid the devastating impacts of climate change. The health sector is a significant contributor to greenhouse gas emissions in developed countries, and its climate impact in low-income countries is growing steadily. This paper reviews and discusses the literature regarding health sector mitigation potential, known and hypothetical co-benefits, and the potential of health information technology, such as eHealth, in climate change mitigation and adaptation. The promising role of eHealth as an adaptation strategy to reduce societal vulnerability to climate change, and the link's between mitigation and adaptation, are also discussed. The topic of environmental eHealth has gained little attention to date, despite its potential to contribute to more sustainable and green health care. A growing number of local and global initiatives on 'green information and communication technology (ICT)' are now mentioning eHealth as a promising technology with the potential to reduce emission rates from ICT use. However, the embracing of eHealth is slow because of limitations in technological infrastructure, capacity and political will. Further research on potential emissions reductions and co-benefits with green ICT, in terms of health outcomes and economic effectiveness, would be valuable to guide development and implementation of eHealth in health sector mitigation and adaptation policies. PMID:22679398

  19. Photosynthetic adaptation strategy of Ulva prolifera floating on the sea surface to environmental changes.

    PubMed

    Zhao, Xinyu; Tang, Xuexi; Zhang, Huanxin; Qu, Tongfei; Wang, Ying

    2016-10-01

    For 8 consecutive years, a green tide has originated in the southern Yellow Sea and spread to the Qingdao offshore area. The causative species, Ulva prolifera, always forms a very thick thallus mat that is capable of drifting long distances over long periods. During this process, although the thalli face disturbance by complex environmental factors, they maintain high biomass and proliferation. We hypothesized that some form of photosynthetic adaptation strategy must exist to protect the thalli. Therefore, we studied the different photosynthetic response characteristics of the surface and lower layers of the floating thallus mats, and investigated the physiological and molecular-level adaptation mechanisms. The results showed that: (1) U. prolifera has strong photosynthetic capability that ensures it can gain sufficient energy to increase its biomass and adapt to long-distance migration. (2) Surface layer thalli adapt to the complex environment by dissipating excess energy via photosynthetic quantum control (energy quenching and energy redistribution between PSII/PSI) to avoid irreversible damage to the photosynthetic system. (3) Lower layer thalli increase their contents of Chlorophyll a (Chl a) and Chlorophyll b (Chl b) and decrease their Chl a/Chl b ratio to improve their ability to use light energy. (4) U. prolifera has strong photosynthetic plasticity and can adapt to frequent exchange between the surface and lower layer environments because of wave disturbance. Pigment component changes, energy quenching, and energy redistribution between PSII/PSI contribute to this photosynthetic plasticity.

  20. Climate change and eHealth: a promising strategy for health sector mitigation and adaptation.

    PubMed

    Holmner, Asa; Rocklöv, Joacim; Ng, Nawi; Nilsson, Maria

    2012-01-01

    Climate change is one of today's most pressing global issues. Policies to guide mitigation and adaptation are needed to avoid the devastating impacts of climate change. The health sector is a significant contributor to greenhouse gas emissions in developed countries, and its climate impact in low-income countries is growing steadily. This paper reviews and discusses the literature regarding health sector mitigation potential, known and hypothetical co-benefits, and the potential of health information technology, such as eHealth, in climate change mitigation and adaptation. The promising role of eHealth as an adaptation strategy to reduce societal vulnerability to climate change, and the link's between mitigation and adaptation, are also discussed. The topic of environmental eHealth has gained little attention to date, despite its potential to contribute to more sustainable and green health care. A growing number of local and global initiatives on 'green information and communication technology (ICT)' are now mentioning eHealth as a promising technology with the potential to reduce emission rates from ICT use. However, the embracing of eHealth is slow because of limitations in technological infrastructure, capacity and political will. Further research on potential emissions reductions and co-benefits with green ICT, in terms of health outcomes and economic effectiveness, would be valuable to guide development and implementation of eHealth in health sector mitigation and adaptation policies.

  1. Climate change and eHealth: a promising strategy for health sector mitigation and adaptation

    PubMed Central

    Holmner, Åsa; Rocklöv, Joacim; Ng, Nawi; Nilsson, Maria

    2012-01-01

    Climate change is one of today's most pressing global issues. Policies to guide mitigation and adaptation are needed to avoid the devastating impacts of climate change. The health sector is a significant contributor to greenhouse gas emissions in developed countries, and its climate impact in low-income countries is growing steadily. This paper reviews and discusses the literature regarding health sector mitigation potential, known and hypothetical co-benefits, and the potential of health information technology, such as eHealth, in climate change mitigation and adaptation. The promising role of eHealth as an adaptation strategy to reduce societal vulnerability to climate change, and the link's between mitigation and adaptation, are also discussed. The topic of environmental eHealth has gained little attention to date, despite its potential to contribute to more sustainable and green health care. A growing number of local and global initiatives on ‘green information and communication technology (ICT)’ are now mentioning eHealth as a promising technology with the potential to reduce emission rates from ICT use. However, the embracing of eHealth is slow because of limitations in technological infrastructure, capacity and political will. Further research on potential emissions reductions and co-benefits with green ICT, in terms of health outcomes and economic effectiveness, would be valuable to guide development and implementation of eHealth in health sector mitigation and adaptation policies. PMID:22679398

  2. Photosynthetic adaptation strategy of Ulva prolifera floating on the sea surface to environmental changes.

    PubMed

    Zhao, Xinyu; Tang, Xuexi; Zhang, Huanxin; Qu, Tongfei; Wang, Ying

    2016-10-01

    For 8 consecutive years, a green tide has originated in the southern Yellow Sea and spread to the Qingdao offshore area. The causative species, Ulva prolifera, always forms a very thick thallus mat that is capable of drifting long distances over long periods. During this process, although the thalli face disturbance by complex environmental factors, they maintain high biomass and proliferation. We hypothesized that some form of photosynthetic adaptation strategy must exist to protect the thalli. Therefore, we studied the different photosynthetic response characteristics of the surface and lower layers of the floating thallus mats, and investigated the physiological and molecular-level adaptation mechanisms. The results showed that: (1) U. prolifera has strong photosynthetic capability that ensures it can gain sufficient energy to increase its biomass and adapt to long-distance migration. (2) Surface layer thalli adapt to the complex environment by dissipating excess energy via photosynthetic quantum control (energy quenching and energy redistribution between PSII/PSI) to avoid irreversible damage to the photosynthetic system. (3) Lower layer thalli increase their contents of Chlorophyll a (Chl a) and Chlorophyll b (Chl b) and decrease their Chl a/Chl b ratio to improve their ability to use light energy. (4) U. prolifera has strong photosynthetic plasticity and can adapt to frequent exchange between the surface and lower layer environments because of wave disturbance. Pigment component changes, energy quenching, and energy redistribution between PSII/PSI contribute to this photosynthetic plasticity. PMID:27262405

  3. Visual search disorders in acute and chronic homonymous hemianopia: lesion effects and adaptive strategies.

    PubMed

    Machner, Björn; Sprenger, Andreas; Sander, Thurid; Heide, Wolfgang; Kimmig, Hubert; Helmchen, Christoph; Kömpf, Detlef

    2009-05-01

    Patients with homonymous hemianopia due to occipital brain lesions show disorders of visual search. In everyday life this leads to difficulties in reading and spatial orientation. It is a matter of debate whether these disorders are due to the brain lesion or rather reflect compensatory eye movement strategies developing over time. For the first time, eye movements of acute hemianopic patients (n= 9) were recorded during the first days following stroke while they performed an exploratory visual-search task. Compared to age-matched control subjects their search duration was prolonged due to increased fixations and refixations, that is, repeated scanning of previously searched locations. Saccadic amplitudes were smaller in patients. Right hemianopic patients were more impaired than left hemianopic patients. The number of fixations and refixations did not differ significantly between both hemifields in the patients. Follow-up of one patient revealed changes of visual search over 18 months. By using more structured scanpaths with fewer saccades his search duration decreased. Furthermore, he developed a more efficient eye-movement strategy by making larger but less frequent saccades toward his blind side. In summary, visual-search behavior of acute hemianopic patients differs from healthy control subjects and from chronic hemianopic patients. We conclude that abnormal visual search in acute hemianopic patients is related to the brain lesion. We provide some evidence for adaptive eye-movement strategies developed over time. These adaptive strategies make the visual search more efficient and may help to compensate for the persisting visual-field loss.

  4. Gradient-based adaptation of continuous dynamic model structures

    NASA Astrophysics Data System (ADS)

    La Cava, William G.; Danai, Kourosh

    2016-01-01

    A gradient-based method of symbolic adaptation is introduced for a class of continuous dynamic models. The proposed model structure adaptation method starts with the first-principles model of the system and adapts its structure after adjusting its individual components in symbolic form. A key contribution of this work is its introduction of the model's parameter sensitivity as the measure of symbolic changes to the model. This measure, which is essential to defining the structural sensitivity of the model, not only accommodates algebraic evaluation of candidate models in lieu of more computationally expensive simulation-based evaluation, but also makes possible the implementation of gradient-based optimisation in symbolic adaptation. The proposed method is applied to models of several virtual and real-world systems that demonstrate its potential utility.

  5. A New Adaptive Image Denoising Method Based on Neighboring Coefficients

    NASA Astrophysics Data System (ADS)

    Biswas, Mantosh; Om, Hari

    2016-03-01

    Many good techniques have been discussed for image denoising that include NeighShrink, improved adaptive wavelet denoising method based on neighboring coefficients (IAWDMBNC), improved wavelet shrinkage technique for image denoising (IWST), local adaptive wiener filter (LAWF), wavelet packet thresholding using median and wiener filters (WPTMWF), adaptive image denoising method based on thresholding (AIDMT). These techniques are based on local statistical description of the neighboring coefficients in a window. These methods however do not give good quality of the images since they cannot modify and remove too many small wavelet coefficients simultaneously due to the threshold. In this paper, a new image denoising method is proposed that shrinks the noisy coefficients using an adaptive threshold. Our method overcomes these drawbacks and it has better performance than the NeighShrink, IAWDMBNC, IWST, LAWF, WPTMWF, and AIDMT denoising methods.

  6. Strategies for a permanent lunar base

    NASA Technical Reports Server (NTRS)

    Duke, M. B.; Mendell, W. W.; Roberts, B. B.

    1985-01-01

    One or more of three possible objectives, encompassing scientific research, lunar resource exploitation for space infrastructure construction, and lunar environment self-sufficiency refinement with a view to future planetary habitation, may be the purpose of manned lunar base activities. Attention is presently given to the possibility that the early phases of all three lunar base orientations may be developed in such a way as to share the greatest number of common elements. An evaluation is made of the cost and complexity of the lunar base, and the Space Transportation System used in conjunction with it, as functions of long term base use strategy.

  7. Personalized articulated atlas with a dynamic adaptation strategy for bone segmentation in CT or CT/MR head and neck images

    NASA Astrophysics Data System (ADS)

    Steger, Sebastian; Jung, Florian; Wesarg, Stefan

    2014-03-01

    This paper presents a novel segmentation method for the joint segmentation of individual bones in CT- or CT/MR- head and neck images. It is based on an articulated atlas for CT images that learned the shape and appearance of the individual bones along with the articulation between them from annotated training instances. First, a novel dynamic adaptation strategy for the atlas is presented in order to increase the rate of successful adaptations. Then, if a corresponding CT image is available the atlas can be enriched with personalized information about shape, appearance and size of the individual bones from that image. Using mutual information, this personalized atlas is adapted to an MR image in order to propagate segmentations. For evaluation, a head and neck bone atlas created from 15 manually annotated training images was adapted to 58 clinically acquired head andneck CT datasets. Visual inspection showed that the automatic dynamic adaptation strategy was successful for all bones in 86% of the cases. This is a 22% improvement compared to the traditional gradient descent based approach. In leave-one-out cross validation manner the average surface distance of the correctly adapted items was found to be 0.6 8mm. In 20 cases corresponding CT/MR image pairs were available and the atlas could be personalized and adapted to the MR image. This was successful in 19 cases.

  8. Design strategies for aptamer-based biosensors.

    PubMed

    Han, Kun; Liang, Zhiqiang; Zhou, Nandi

    2010-01-01

    Aptamers have been widely used as recognition elements for biosensor construction, especially in the detection of proteins or small molecule targets, and regarded as promising alternatives for antibodies in bioassay areas. In this review, we present an overview of reported design strategies for the fabrication of biosensors and classify them into four basic modes: target-induced structure switching mode, sandwich or sandwich-like mode, target-induced dissociation/displacement mode and competitive replacement mode. In view of the unprecedented advantages brought about by aptamers and smart design strategies, aptamer-based biosensors are expected to be one of the most promising devices in bioassay related applications.

  9. Alternative Strategies for the Problem Learner: Student Support Team Strategies Manual. A Handbook collected and Adapted by the Georgia Learning Resources Network.

    ERIC Educational Resources Information Center

    Georgia Learning Resources System/Child Serve, Columbus.

    The manual presents the framework of the Student Support Team (SST), an approach involving two or more professionals who develop alternative instructional strategies for students in lieu of special education placement. General considerations are offered for classroom management, curriculum adaptations, and adaptations for the visually and hearing…

  10. 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.

  11. 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. PMID:15267070

  12. Adapting agriculture to climate change in Kenya: household strategies and determinants.

    PubMed

    Bryan, Elizabeth; Ringler, Claudia; Okoba, Barrack; Roncoli, Carla; Silvestri, Silvia; Herrero, Mario

    2013-01-15

    Countries in Sub-Saharan Africa are particularly vulnerable to climate change, given dependence on agricultural production and limited adaptive capacity. Based on farm household and Participatory Rural Appraisal data collected from districts in various agroecological zones in Kenya, this paper examines farmers' perceptions of climate change, ongoing adaptation measures, and factors influencing farmers' decisions to adapt. The results show that households face considerable challenges in adapting to climate change. While many households have made small adjustments to their farming practices in response to climate change (in particular, changing planting decisions), few households are able to make more costly investments, for example in agroforestry or irrigation, although there is a desire to invest in such measures. This emphasizes the need for greater investments in rural and agricultural development to support the ability of households to make strategic, long-term decisions that affect their future well-being.

  13. Constructing evidence-based treatment strategies using methods from computer science

    PubMed Central

    Pineau, Joelle; Bellemare, Marc G.; Rush, A. John; Ghizaru, Adrian; Murphy, Susan A.

    2007-01-01

    This paper details a new methodology, instance–based reinforcement learning, for constructing adaptive treatment strategies from randomized trials. Adaptive treatment strategies are operationalized clinical guidelines which recommend the next best treatment for an individual based on his/her personal characteristics and response to earlier treatments. The instance-based reinforcement learning methodology comes from the computer science literature, where it was developed to optimize sequences of actions in an evolving, time varying system. When applied in the context of treatment design, this method provides the means to evaluate both the therapeutic and diagnostic effects of treatments in constructing an adaptive treatment strategy. The methodology is illustrated with data from the STAR*D trial, a multi-step randomized study of treatment alternatives for individuals with treatment-resistant major depressive disorder. PMID:17320311

  14. Constructing evidence-based treatment strategies using methods from computer science.

    PubMed

    Pineau, Joelle; Bellemare, Marc G; Rush, A John; Ghizaru, Adrian; Murphy, Susan A

    2007-05-01

    This paper details a new methodology, instance-based reinforcement learning, for constructing adaptive treatment strategies from randomized trials. Adaptive treatment strategies are operationalized clinical guidelines which recommend the next best treatment for an individual based on his/her personal characteristics and response to earlier treatments. The instance-based reinforcement learning methodology comes from the computer science literature, where it was developed to optimize sequences of actions in an evolving, time varying system. When applied in the context of treatment design, this method provides the means to evaluate both the therapeutic and diagnostic effects of treatments in constructing an adaptive treatment strategy. The methodology is illustrated with data from the STAR*D trial, a multi-step randomized study of treatment alternatives for individuals with treatment-resistant major depressive disorder.

  15. Link-based formalism for time evolution of adaptive networks

    NASA Astrophysics Data System (ADS)

    Zhou, Jie; Xiao, Gaoxi; Chen, Guanrong

    2013-09-01

    Network topology and nodal dynamics are two fundamental stones of adaptive networks. Detailed and accurate knowledge of these two ingredients is crucial for understanding the evolution and mechanism of adaptive networks. In this paper, by adopting the framework of the adaptive SIS model proposed by Gross [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.96.208701 96, 208701 (2006)] and carefully utilizing the information of degree correlation of the network, we propose a link-based formalism for describing the system dynamics with high accuracy and subtle details. Several specific degree correlation measures are introduced to reveal the coevolution of network topology and system dynamics.

  16. Assessing effects of climate change and adaptation strategies on irrigated pastures using DAISY

    NASA Astrophysics Data System (ADS)

    Hagimoto, Y.; Cuenca, R. H.

    2013-12-01

    The DAISY ecological model was applied for the flood-irrigated cool-season pastures in the Upper Klamath Basin, Oregon to study 1) the current condition of the pastures in the semi-arid environment, 2) effects of projected climate change, and 3) effects of introducing white clover and a sprinkler system as a potential adaptation strategy. The calibrated model indicated that productivity of the cool-season pastures was limited primarily by nitrogen (N) availability and temperature. The results of our scenario analysis indicated that the projected climate change would increase seasonal forage production (YF) and crop water use (AET) due to longer and warmer growing season. This study also found that introduction of white clover would significantly increase YF without changing AET by improving N availability due to increased nutrients deposition by cattle and increased symbiotic N fixation by white clover. In consequence, the mixed pasture could significantly improve water use efficiency (YF/AET) and, therefore the adaptability of the pasture in an area with high value water. Installing sprinkler system to the mixed pasture would increase YF by increasing net N input by increasing N mineralization and reducing denitrification. Furthermore, upgraded irrigation systems could increase water availability of the area during growing season by releasing significant amount of subsurface water to nearby surface water pools. This study demonstrated that ecological models such as DAISY can be a useful tool to model pasture systems and assess effects of projected climate changes and adaptation strategies.

  17. Confronting Complexity: Adaptation Strategies for Managing Biodiversity in the Face of Rapid Climate Change

    NASA Astrophysics Data System (ADS)

    Graumlich, L.; Cross, M.; Tabor, G.; Enquist, C.; Rowland, E.

    2008-12-01

    There is no doubt that the montane landscapes of the Western US are being transformed by a complex interplay of changing climate, growing urban centers, altered disturbance regimes and invasive species. Among this suite of drivers of change, climate change has emerged as a critical concern of managers and agencies concerned with protected areas and protected species. These managers are under intensifying pressure to come up with scientifically robust and socially acceptable plans for adaptation to climate change. Those charged with managing biodiversity in the face of change have turned to the scientific community for decision support tools that they can implement immediately to proactively address adaptation. Broadly speaking, this is good news for that part of the scientific community that is keen to engage in translational science, even if the timeline is a bit breathtaking. A key challenge in this endeavor is to find common ground between all those issues that define complexity for the scientific community (e.g., nonlinearity, thresholds, cross-scale interactions) and a range of issues that define complexity for the management community (e.g., multiple jurisdictions, regulatory issues, values of diverse stakeholders). In this talk, we reflect on emerging strategies that seek to infuse adaptation into climate change into landscape scale conservation planning in the Greater Yellowstone Ecosystem and the Southwestern US. We describe how climate change challenges current adaptive management practices to 1) anticipate a broad range of climate trajectories, including no-analog scenarios, and 2) to actively incorporate new information from positive outcomes and negative consequences of management interventions. The success of such adaption hinges on public understanding and acceptance of the process of adaption, which, in turn, demands even greater attention to be paid to increasing public understanding of the intersection of climate change and the role of

  18. Cell-based strategies for vascular regeneration.

    PubMed

    Zou, Tongqiang; Fan, Jiabing; Fartash, Armita; Liu, Haifeng; Fan, Yubo

    2016-05-01

    Vascular regeneration is known to play an essential role in the repair of injured tissues mainly through accelerating the repair of vascular injury caused by vascular diseases, as well as the recovery of ischemic tissues. However, the clinical vascular regeneration is still challenging. Cell-based therapy is thought to be a promising strategy for vascular regeneration, since various cells have been identified to exert important influences on the process of vascular regeneration such as the enhanced endothelium formation on the surface of vascular grafts, and the induction of vessel-like network formation in the ischemic tissues. Here are a vast number of diverse cell-based strategies that have been extensively studied in vascular regeneration. These strategies can be further classified into three main categories, including cell transplantation, construction of tissue-engineered grafts, and surface modification of scaffolds. Cells used in these strategies mainly refer to terminally differentiated vascular cells, pluripotent stem cells, multipotent stem cells, and unipotent stem cells. The aim of this review is to summarize the reported research advances on the application of various cells for vascular regeneration, yielding insights into future clinical treatment for injured tissue/organ. PMID:26864677

  19. Long-term strategies of climate change adaptation to manage flooding events in urban areas

    NASA Astrophysics Data System (ADS)

    Pouget, Laurent; Russo, Beniamino; Redaño, Angel; Ribalaygua, Jaime

    2010-05-01

    Heavy and sudden rainfalls regularly affect the Mediterranean area, so a great number of people and buildings are exposed to the risk of rain-generated floods. Climate change is expected to modify this risk and, in the case that extreme rainfalls increase in frequencies and intensity, this could result in important damages, particularly in urban areas. This paper presents a project that aims to determine adaptation strategies to future flood risks in urban areas. It has been developed by a panel of water companies (R+i Alliance funding), and includes the evaluation of the climate change impact on the extreme rainfall, the use of innovative modelling tools to accurately forecast the flood risk and, finally, the definition of a pro-active and long-term planning against floods. This methodology has been applied in the city of Barcelona. Current climate models give some projections that are not directly applicable for flood risk studies, either because they do not have an adequate spatial and temporal resolution, or because they do not consider some important local factors, such as orography. These points have been considered within the project, when developing the design storms corresponding to future climatic conditions (e.g. years 2030 or 2050). The methodology uses statistical downscaling techniques based on global climate models predictions, including corrections for extreme events and convective storms, as well as temporal downscaling based on historical observations. The design storms created are used in combination with the predictions of sea level rise and land use evolutions to determine the future risk of flooding in the area of study. Once the boundary conditions are known, an accurate flood hazard assessment is done. It requires a local knowledge of the flow parameters in the whole analyzed domain. In urban catchments, in order to fulfill this requirement, powerful hydrological and hydraulic tools and detailed topographic data represent the unique way for

  20. Long-term fasting and realimentation in hypogean and epigean isopods: a proposed adaptive strategy for groundwater organisms.

    PubMed

    Hervant, Frédéric; Renault, David

    2002-07-01

    The effects of long-term fasting and subsequent refeeding on digestive physiology and energy metabolism were investigated in a subterranean aquatic crustacean, Stenasellus virei, and in a morphologically similar surface-dwelling species, Asellus aquaticus. Metabolic response to food deprivation was monophasic in A. aquaticus, with an immediate, large decrease in all energy reserves. In contrast, S. virei displayed three successive periods of phosphageno-glucidic, lipidic and, finally, proteo-lipidic-dominant catabolism over the course of the nutritional stress. To represent the responses of subterranean crustaceans to food stress and renutrition, a sequential energy strategy was hypothesized, suggesting that four successive phases (called stress, transition, adaptation and recovery) can be distinguished. Based on these results, a general adaptive strategy for groundwater organisms was proposed. Their remarkable resistance to long-term fasting may be partly explained by (1) a depressed metabolism, during which they mainly subsist on lipid stores, (2) a prolonged state of glycogen- and protein-sparing, (3) low energetic requirements and (4) large body stores. In addition, these groundwater species displayed high recovery abilities during refeeding, showing an optimal utilization of available food and a rapid restoration of their body reserves. These adaptive responses might be considered for numerous subterranean organisms as an efficient energy-saving strategy in a harsh and unpredictable environment where fasting (and/or hypoxic) periods of variable duration alternate with sporadic feeding events (and/or normoxic periods). Therefore, food-limited and/or hypoxia-tolerant groundwater species appear to be good examples of animals representing a low-energy system.

  1. The FIGS (focused identification of germplasm strategy) approach identifies traits related to drought adaptation in Vicia faba genetic resources.

    PubMed

    Khazaei, Hamid; Street, Kenneth; Bari, Abdallah; Mackay, Michael; Stoddard, Frederick L

    2013-01-01

    Efficient methods to explore plant agro-biodiversity for climate change adaptive traits are urgently required. The focused identification of germplasm strategy (FIGS) is one such approach. FIGS works on the premise that germplasm is likely to reflect the selection pressures of the environment in which it developed. Environmental parameters describing plant germplasm collection sites are used as selection criteria to improve the probability of uncovering useful variation. This study was designed to test the effectiveness of FIGS to search a large faba bean (Vicia faba L.) collection for traits related to drought adaptation. Two sets of faba bean accessions were created, one from moisture-limited environments, and the other from wetter sites. The two sets were grown under well watered conditions and leaf morpho-physiological traits related to plant water use were measured. Machine-learning algorithms split the accessions into two groups based on the evaluation data and the groups created by this process were compared to the original climate-based FIGS sets. The sets defined by trait data were in almost perfect agreement to the FIGS sets, demonstrating that ecotypic differentiation driven by moisture availability has occurred within the faba bean genepool. Leaflet and canopy temperature as well as relative water content contributed more than other traits to the discrimination between sets, indicating that their utility as drought-tolerance selection criteria for faba bean germplasm. This study supports the assertion that FIGS could be an effective tool to enhance the discovery of new genes for abiotic stress adaptation.

  2. Distributed adaptive simulation through standards-based integration of simulators and adaptive learning systems.

    PubMed

    Bergeron, Bryan; Cline, Andrew; Shipley, Jaime

    2012-01-01

    We have developed a distributed, standards-based architecture that enables simulation and simulator designers to leverage adaptive learning systems. Our approach, which incorporates an electronic competency record, open source LMS, and open source microcontroller hardware, is a low-cost, pragmatic option to integrating simulators with traditional courseware. PMID:22356955

  3. Motion Analysis of 100 Mediastinal Lymph Nodes: Potential Pitfalls in Treatment Planning and Adaptive Strategies

    SciTech Connect

    Pantarotto, Jason R.; Piet, Anna H.M.; Vincent, Andrew; Soernsen de Koste, John R. van; Senan, Suresh

    2009-07-15

    Purpose: The motion of mediastinal lymph nodes may undermine local control with involved-field radiotherapy. We studied patterns of nodal and tumor motion in 41 patients with lung cancer. Methods and Materials: Four-dimensional (4D) computed tomography planning scans were retrospectively evaluated to identify patients with clearly visible mediastinal lymph nodes. One hundred nodes from 14 patients with Stage I and 27 patients with Stage III were manually contoured in all 4D computed tomography respiratory phases. Motion was derived from changes in the nodal center-of-mass position. Primary tumors were also delineated in all phases for 16 patients with Stage III disease. Statistical analysis included a multivariate mixed-effects model of grouped data. Results: Average 3D nodal motion during quiet breathing was 0.68 cm (range, 0.17-1.64 cm); 77% moved greater than 0.5 cm, and 10% moved greater than 1.0 cm. Motion was greatest in the lower mediastinum (p = 0.002), and nodes measuring 2 cm or greater in diameter showed motion similar to that in smaller nodes. In 11 of 16 patients studied, at least one node moved more than the corresponding primary tumor. No association between 3D primary tumor motion and nodal motion was observed. For mobile primary tumors, phase offsets between the primary tumor and nodes of two or more and three or more phases were observed for 33% and 12% of nodes, respectively. Conclusions: Mediastinal nodal motion is common, with phase offsets seen between the primary tumor and different nodes in the same patient. Patient-specific information is needed to ensure geometric coverage, and adaptive strategies based solely on the primary tumor may be misleading.

  4. How Teaching Science Using Project-Based Learning Strategies Affects the Classroom Learning Environment

    ERIC Educational Resources Information Center

    Hugerat, Muhamad

    2016-01-01

    This study involved 458 ninth-grade students from two different Arab middle schools in Israel. Half of the students learned science using project-based learning strategies and the other half learned using traditional methods (non-project-based). The classes were heterogeneous regarding their achievements in the sciences. The adapted questionnaire…

  5. Adaptive dynamic range optimization (ADRO): a digital amplification strategy for hearing aids and cochlear implants.

    PubMed

    Blamey, Peter J

    2005-01-01

    Adaptive dynamic range optimization (ADRO) is an amplification strategy that uses digital signal processing techniques to improve the audibility, comfort, and intelligibility of sounds for people who use cochlear implants and/or hearing aids. The strategy uses statistical analysis to select the most information-rich section of the input dynamic range in multiple-frequency channels. Fuzzy logic rules control the gain in each frequency channel so that the selected section of the dynamic range is presented at an audible and comfortable level. The ADRO processing thus adaptively optimizes the dynamic range of the signal in multiple-frequency channels. Clinical studies show that ADRO can be fitted easily to all degrees of hearing loss for hearing aids and cochlear implants in a direct and intuitive manner, taking the preferences of the listener into account. The result is high acceptance by new and experienced hearing aid users and strong preferences for ADRO compared with alternative amplification strategies. The ADRO processing is particularly well suited to bimodal and hybrid stimulation which combine electric and acoustic stimulation in opposite ears or in the same ear, respectively.

  6. Adaptive Dynamic Range Optimization (ADRO): A Digital Amplification Strategy for Hearing Aids and Cochlear Implants

    PubMed Central

    Blamey, Peter J.

    2005-01-01

    Adaptive dynamic range optimization (ADRO) is an amplification strategy that uses digital signal processing techniques to improve the audibility, comfort, and intelligibility of sounds for people who use cochlear implants and/or hearing aids. The strategy uses statistical analysis to select the most information-rich section of the input dynamic range in multiple-frequency channels. Fuzzy logic rules control the gain in each frequency channel so that the selected section of the dynamic range is presented at an audible and comfortable level. The ADRO processing thus adaptively optimizes the dynamic range of the signal in multiple-frequency channels. Clinical studies show that ADRO can be fitted easily to all degrees of hearing loss for hearing aids and cochlear implants in a direct and intuitive manner, taking the preferences of the listener into account. The result is high acceptance by new and experienced hearing aid users and strong preferences for ADRO compared with alternative amplification strategies. The ADRO processing is particularly well suited to bimodal and hybrid stimulation which combine electric and acoustic stimulation in opposite ears or in the same ear, respectively. PMID:16012705

  7. Roy’s Adaptation Model-Based Patient Education for Promoting the Adaptation of Hemodialysis Patients

    PubMed Central

    Afrasiabifar, Ardashir; Karimi, Zohreh; Hassani, Parkhideh

    2013-01-01

    Background In addition to physical adaptation and psychosocial adjustment to chronic renal disease, hemodialysis (HD) patients must also adapt to dialysis therapy plan. Objectives The aim of the present study was to examine the effect of Roy’s adaptation model-based patient education on adaptation of HD patients. Patients and Methods This study is a semi-experimental research that was conducted with the participation of all patients with end-stage renal disease referred to the dialysis unit of Shahid Beheshti Hospital of Yasuj city, 2010. A total of 59 HD patients were randomly allocated to two groups of test and control. Data were collected by a questionnaire based on the Roy’s Adaptation Model (RAM). Validity and reliability of the questionnaire were approved. Patient education was determined by eight one-hour sessions over eight weeks. At the end of the education plan, the patients were given an educational booklet containing the main points of self-care for HD patients. The effectiveness of education plan was assessed two months after plan completion and data were compared with the pre-education scores. All analyses were conducted using the SPSS software (version 16) through descriptive and inferential statistics including correlation, t-test, ANOVA and ANCOVA tests. Results The results showed significant differences in the mean scores of physiological and self-concept models between the test and control groups (P = 0.01 and P = 0.03 respectively). Also a statistical difference (P = 0.04) was observed in the mean scores of the role function mode of both groups. There was no significant difference in the mean scores of interdependence modes between the two groups. Conclusions RAM based patient education could improve the patients’ adaptation in physiologic and self-concept modes. In addition to suggesting further research in this area, nurses are recommended to pay more attention in applying RAM in dialysis centers. PMID:24396575

  8. Variability in thermal and phototactic preferences in Drosophila may reflect an adaptive bet‐hedging strategy

    PubMed Central

    Kain, Jamey S.; Zhang, Sarah; Akhund‐Zade, Jamilla; Samuel, Aravinthan D. T.; Klein, Mason; de Bivort, Benjamin L.

    2015-01-01

    Organisms use various strategies to cope with fluctuating environmental conditions. In diversified bet‐hedging, a single genotype exhibits phenotypic heterogeneity with the expectation that some individuals will survive transient selective pressures. To date, empirical evidence for bet‐hedging is scarce. Here, we observe that individual Drosophila melanogaster flies exhibit striking variation in light‐ and temperature‐preference behaviors. With a modeling approach that combines real world weather and climate data to simulate temperature preference‐dependent survival and reproduction, we find that a bet‐hedging strategy may underlie the observed interindividual behavioral diversity. Specifically, bet‐hedging outcompetes strategies in which individual thermal preferences are heritable. Animals employing bet‐hedging refrain from adapting to the coolness of spring with increased warm‐seeking that inevitably becomes counterproductive in the hot summer. This strategy is particularly valuable when mean seasonal temperatures are typical, or when there is considerable fluctuation in temperature within the season. The model predicts, and we experimentally verify, that the behaviors of individual flies are not heritable. Finally, we model the effects of historical weather data, climate change, and geographic seasonal variation on the optimal strategies underlying behavioral variation between individuals, characterizing the regimes in which bet‐hedging is advantageous. PMID:26531165

  9. Adaptive strategies in the double-extremophilic prokaryotes inhabiting soda lakes.

    PubMed

    Banciu, Horia Leonard; Muntyan, Maria S

    2015-06-01

    Haloalkaliphiles are double extremophilic organisms thriving both at high salinity and alkaline pH. Although numerous haloalkaliphilic representatives have been identified among Archaea and Bacteria over the past 15 years, the adaptations underlying their prosperity at haloalkaline conditions are scarcely known. A multi-level adaptive strategy was proposed to occur in haloalkaliphilic organisms isolated from saline alkaline and soda environments including adjustments in the cell wall structure, plasma membrane lipid composition, membrane transport systems, bioenergetics, and osmoregulation. Isolation of chemolithoautotrophic sulfur-oxidizing γ-Proteobacteria from soda lakes allowed the elucidation of the structural and physiological differences between haloalkaliphilic (prefer NaCl) and natronophilic (prefer NaHCO3/Na2CO3, i.e. soda) microbes.

  10. Adaptive Device Context Based Mobile Learning Systems

    ERIC Educational Resources Information Center

    Pu, Haitao; Lin, Jinjiao; Song, Yanwei; Liu, Fasheng

    2011-01-01

    Mobile learning is e-learning delivered through mobile computing devices, which represents the next stage of computer-aided, multi-media based learning. Therefore, mobile learning is transforming the way of traditional education. However, as most current e-learning systems and their contents are not suitable for mobile devices, an approach for…

  11. SU-E-J-153: MRI Based, Daily Adaptive Radiotherapy for Rectal Cancer: Contour Adaptation

    SciTech Connect

    Kleijnen, J; Burbach, M; Verbraeken, T; Weggers, R; Zoetelief, A; Reerink, O; Lagendijk, J; Raaymakers, B; Asselen, B

    2014-06-01

    Purpose: A major hurdle in adaptive radiotherapy is the adaptation of the planning MRI's delineations to the daily anatomy. We therefore investigate the accuracy and time needed for online clinical target volume (CTV) adaptation by radiation therapists (RTT), to be used in MRI-guided adaptive treatments on a MRI-Linac (MRL). Methods: Sixteen patients, diagnosed with early stage rectal cancer, underwent a T2-weighted MRI prior to each fraction of short-course radiotherapy, resulting in 4–5 scans per patient. On these scans, the CTV was delineated according to guidelines by an experienced radiation oncologist (RO) and considered to be the gold standard. For each patient, the first MRI was considered as the planning MRI and matched on bony anatomy to the 3–4 daily MRIs. The planning MRI's CTV delineation was rigidly propagated to the daily MRI scans as a proposal for adaptation. Three RTTs in training started the adaptation of the CTV conform guidelines, after a two hour training lecture and a two patient (n=7) training set. To assess the inter-therapist variation, all three RTTs altered delineations of 3 patients (n=12). One RTT altered the CTV delineations (n=53) of the remaining 11 patients. Time needed for adaptation of the CTV to guidelines was registered.As a measure of agreement, the conformity index (CI) was determined between the RTTs' delineations as a group. Dice similarity coefficients were determined between delineations of the RTT and the RO. Results: We found good agreement between RTTs' and RO's delineations (average Dice=0.91, SD=0.03). Furthermore, the inter-observer agreement between the RTTs was high (average CI=0.94, SD=0.02). Adaptation time reduced from 10:33 min (SD= 3:46) to 2:56 min (SD=1:06) between the first and last ten delineations, respectively. Conclusion: Daily CTV adaptation by RTTs, seems a feasible and safe way to introduce daily, online MRI-based plan adaptation for a MRL.

  12. Adaptive sparse polynomial chaos expansion based on least angle regression

    NASA Astrophysics Data System (ADS)

    Blatman, Géraud; Sudret, Bruno

    2011-03-01

    Polynomial chaos (PC) expansions are used in stochastic finite element analysis to represent the random model response by a set of coefficients in a suitable (so-called polynomial chaos) basis. The number of terms to be computed grows dramatically with the size of the input random vector, which makes the computational cost of classical solution schemes (may it be intrusive (i.e. of Galerkin type) or non intrusive) unaffordable when the deterministic finite element model is expensive to evaluate. To address such problems, the paper describes a non intrusive method that builds a sparse PC expansion. First, an original strategy for truncating the PC expansions, based on hyperbolic index sets, is proposed. Then an adaptive algorithm based on least angle regression (LAR) is devised for automatically detecting the significant coefficients of the PC expansion. Beside the sparsity of the basis, the experimental design used at each step of the algorithm is systematically complemented in order to avoid the overfitting phenomenon. The accuracy of the PC metamodel is checked using an estimate inspired by statistical learning theory, namely the corrected leave-one-out error. As a consequence, a rather small number of PC terms are eventually retained ( sparse representation), which may be obtained at a reduced computational cost compared to the classical "full" PC approximation. The convergence of the algorithm is shown on an analytical function. Then the method is illustrated on three stochastic finite element problems. The first model features 10 input random variables, whereas the two others involve an input random field, which is discretized into 38 and 30 - 500 random variables, respectively.

  13. An adaptive differential evolution algorithm with novel mutation and crossover strategies for global numerical optimization.

    PubMed

    Islam, Sk Minhazul; Das, Swagatam; Ghosh, Saurav; Roy, Subhrajit; Suganthan, Ponnuthurai Nagaratnam

    2012-04-01

    Differential evolution (DE) is one of the most powerful stochastic real parameter optimizers of current interest. In this paper, we propose a new mutation strategy, a fitness-induced parent selection scheme for the binomial crossover of DE, and a simple but effective scheme of adapting two of its most important control parameters with an objective of achieving improved performance. The new mutation operator, which we call DE/current-to-gr_best/1, is a variant of the classical DE/current-to-best/1 scheme. It uses the best of a group (whose size is q% of the population size) of randomly selected solutions from current generation to perturb the parent (target) vector, unlike DE/current-to-best/1 that always picks the best vector of the entire population to perturb the target vector. In our modified framework of recombination, a biased parent selection scheme has been incorporated by letting each mutant undergo the usual binomial crossover with one of the p top-ranked individuals from the current population and not with the target vector with the same index as used in all variants of DE. A DE variant obtained by integrating the proposed mutation, crossover, and parameter adaptation strategies with the classical DE framework (developed in 1995) is compared with two classical and four state-of-the-art adaptive DE variants over 25 standard numerical benchmarks taken from the IEEE Congress on Evolutionary Computation 2005 competition and special session on real parameter optimization. Our comparative study indicates that the proposed schemes improve the performance of DE by a large magnitude such that it becomes capable of enjoying statistical superiority over the state-of-the-art DE variants for a wide variety of test problems. Finally, we experimentally demonstrate that, if one or more of our proposed strategies are integrated with existing powerful DE variants such as jDE and JADE, their performances can also be enhanced.

  14. Water law as an adaptation strategy for global water scarcity in the future

    NASA Astrophysics Data System (ADS)

    Kakinuma, K.; Yoshikawa, S.; Endo, T.; Kanae, S.

    2014-12-01

    Water scarcity due to climate changes and growing human population is a major concern for the world. Adaptation and mitigation strategies should be developed for water scarcity in the future. Previous studies assessed the future water availability by hard technology (e.g., reservoirs, reclaimed and desalinated water plants) as adaptation strategies. On the other hand, soft path such as water law and policy would also be important for adaptation strategies. Water transfers is reallocation of water among water users. For example, distribution of the amount of available water is often heterogeneous especially during drought periods. If water transfers are permitted in these areas, water can be moved from surplus areas/sections to critical need areas/sections. There are several studies which describe the water transfer at the local scales (i.e., water bank in California), however the factors that determined the establishment of water transfer are not clear. If we can detect the factors, it could be used to estimate in which areas the water transfer would come into existence. This in turn would reduce the water stress. Here, we focus on historical interaction between human activity and water environments. Generally, rules of water use are developed by repeated discussion among water users. The frequency of these discussions would be related with their land use, frequency of drought and water resource sizes. For example, people in rice crop area need to discuss about water allocation compared to wheat crop area. Therefore, we examine the relationship between the permission of water transfer and factors such as water environment and human activity in the world.

  15. Combining Adaptive Hypermedia with Project and Case-Based Learning

    ERIC Educational Resources Information Center

    Papanikolaou, Kyparisia; Grigoriadou, Maria

    2009-01-01

    In this article we investigate the design of educational hypermedia based on constructivist learning theories. According to the principles of project and case-based learning we present the design rational of an Adaptive Educational Hypermedia system prototype named MyProject; learners working with MyProject undertake a project and the system…

  16. Feasible adaptation strategies for increased risk of flooding in cities due to climate change.

    PubMed

    Arnbjerg-Nielsen, K; Fleischer, H S

    2009-01-01

    Northern Europe is one of the regions where more frequent and more severe storms and storm surges are expected due to climatic changes. In order to maintain an acceptable risk of flooding suitable adaptation strategies must be defined and implemented. Optimum solutions demand collaboration of different professionals and thus simple graphical means must be employed to illustrate the economic impacts of the change in risk of flooding. A case study indicates that urban drainage infrastructure capacity should be upgraded while there is currently no economic incentive to improve protection against sea surges.

  17. Goal orientation and work role performance: predicting adaptive and proactive work role performance through self-leadership strategies.

    PubMed

    Marques-Quinteiro, Pedro; Curral, Luís Alberto

    2012-01-01

    This article explores the relationship between goal orientation, self-leadership dimensions, and adaptive and proactive work role performances. The authors hypothesize that learning orientation, in contrast to performance orientation, positively predicts proactive and adaptive work role performances and that this relationship is mediated by self-leadership behavior-focused strategies. It is posited that self-leadership natural reward strategies and thought pattern strategies are expected to moderate this relationship. Workers (N = 108) from a software company participated in this study. As expected, learning orientation did predict adaptive and proactive work role performance. Moreover, in the relationship between learning orientation and proactive work role performance through self-leadership behavior-focused strategies, a moderated mediation effect was found for self-leadership natural reward and thought pattern strategies. In the end, the authors discuss the results and implications are discussed and future research directions are proposed.

  18. Goal orientation and work role performance: predicting adaptive and proactive work role performance through self-leadership strategies.

    PubMed

    Marques-Quinteiro, Pedro; Curral, Luís Alberto

    2012-01-01

    This article explores the relationship between goal orientation, self-leadership dimensions, and adaptive and proactive work role performances. The authors hypothesize that learning orientation, in contrast to performance orientation, positively predicts proactive and adaptive work role performances and that this relationship is mediated by self-leadership behavior-focused strategies. It is posited that self-leadership natural reward strategies and thought pattern strategies are expected to moderate this relationship. Workers (N = 108) from a software company participated in this study. As expected, learning orientation did predict adaptive and proactive work role performance. Moreover, in the relationship between learning orientation and proactive work role performance through self-leadership behavior-focused strategies, a moderated mediation effect was found for self-leadership natural reward and thought pattern strategies. In the end, the authors discuss the results and implications are discussed and future research directions are proposed. PMID:23094471

  19. Adapting a Master's Course to the Web: Principles, Strategies and Recommendations.

    ERIC Educational Resources Information Center

    Bichelmeyer, Barbara A.; Misanchuk, Melanie; Malopinsky, Larissa

    The purpose of this paper is to describe the process of adaptation of an Instructional Design and Development course from a residential course to a Web-based course offered in the Distance Masters program in Instructional Systems Technology at Indiana University. Lessons from the literature are discussed, followed by a description of the Web-based…

  20. Adaptive strategies for graph-state growth in the presence of monitored errors

    NASA Astrophysics Data System (ADS)

    Campbell, Earl T.; Fitzsimons, Joseph; Benjamin, Simon C.; Kok, Pieter

    2007-04-01

    Graph states (or cluster states) are the entanglement resource that enables one-way quantum computing. They can be grown by projective measurements on the component qubits. Such measurements typically carry a significant failure probability. Moreover, they may generate imperfect entanglement. Here we describe strategies to adapt growth operations in order to cancel incurred errors. Nascent states that initially deviate from the ideal graph states evolve toward the desired high fidelity resource without impractical overheads. Our analysis extends the diagrammatic language of graph states to include characteristics such as tilted vertices, weighted edges, and partial fusion, which arise from experimental imperfections. The strategies we present are relevant to parity projection schemes such as optical path erasure with distributed matter qubits.

  1. Adaptive SVD-Based Digital Image Watermarking

    NASA Astrophysics Data System (ADS)

    Shirvanian, Maliheh; Torkamani Azar, Farah

    Digital data utilization along with the increase popularity of the Internet has facilitated information sharing and distribution. However, such applications have also raised concern about copyright issues and unauthorized modification and distribution of digital data. Digital watermarking techniques which are proposed to solve these problems hide some information in digital media and extract it whenever needed to indicate the data owner. In this paper a new method of image watermarking based on singular value decomposition (SVD) of images is proposed which considers human visual system prior to embedding watermark by segmenting the original image into several blocks of different sizes, with more density in the edges of the image. In this way the original image quality is preserved in the watermarked image. Additional advantages of the proposed technique are large capacity of watermark embedding and robustness of the method against different types of image manipulation techniques.

  2. CRISPR-Based Adaptive Immune Systems

    PubMed Central

    Terns, Michael P.; Terns, Rebecca M.

    2011-01-01

    CRISPR-Cas systems are recently discovered, RNA-based immune systems that control invasions of viruses and plasmids in archaea and bacteria. Prokaryotes with CRISPR-Cas immune systems capture short invader sequences within the CRISPR loci in their genomes, and small RNAs produced from the CRISPR loci (CRISPR (cr)RNAs) guide Cas proteins to recognize and degrade (or otherwise silence) the invading nucleic acids. There are multiple variations of the pathway found among prokaryotes, each mediated by largely distinct components and mechanisms that we are only beginning to delineate. Here we will review our current understanding of the remarkable CRISPR-Cas pathways with particular attention to studies relevant to systems found in the archaea. PMID:21531607

  3. An innovative cross-sectoral method for implementation of trade-off adaptation strategy assessment under climate change

    NASA Astrophysics Data System (ADS)

    Tsao, Jung-Hsuan; Tung, Ching-Pin; Liu, Tzu-Ming

    2014-05-01

    Climate change will increase sharp risks to the water and food supply in coming decades. Although impact assessment and adaptation evaluation has been discussed a lot in recent years, the importance of adaptation implement should not be ignored. In Taiwan, and elsewhere, fallow is an option of adaptation strategy under climate change. Fallow would improve the water scarcity of domestic use, but the food security might be threatened. The trade-off effects of adaptation actions are just like the side effects of medicine which cannot be avoided. Thus, managing water resources with an integrated approach will be urgent. This study aims to establish a cross-sectoral framework for implementation the trade-off adaptation strategy. Not only fallow, but also other trade-off strategy like increasing the percentage of national grain self-sufficiency would be analyzed by a rational decision process. The recent percentage of grain self-sufficiency in Taiwan is around 32, which was decreasing from 53 thirty years ago. Yet, the goal of increasing grain self-sufficiency means much more water must be used in agriculture. In that way, domestic users may face the water shortage situation. Considering the conflicts between water supply and food security, the concepts from integrative negotiation are appropriate to apply. The implementation of trade-off adaptation strategies needs to start by quantifying the utility of water supply and food security were be quantified. Next, each side's bottom line can be found by BATNA (Best Alternative to a Negotiated Agreement) and ZOPA (Zone of Possible Agreement). ZOPA provides the entire possible outcomes, and BATNA ensures the efficiency of adaptation actions by moving along with Pareto frontier. Therefore, the optimal percentage of fallow and grain self-sufficiency can be determined. Furthermore, BATNA also provides the pathway step by step which can be a guideline of adaptation strategies. This framework allows analysts and stakeholder to

  4. Visual search disorders in acute and chronic homonymous hemianopia: lesion effects and adaptive strategies.

    PubMed

    Machner, Björn; Sprenger, Andreas; Sander, Thurid; Heide, Wolfgang; Kimmig, Hubert; Helmchen, Christoph; Kömpf, Detlef

    2009-05-01

    Patients with homonymous hemianopia due to occipital brain lesions show disorders of visual search. In everyday life this leads to difficulties in reading and spatial orientation. It is a matter of debate whether these disorders are due to the brain lesion or rather reflect compensatory eye movement strategies developing over time. For the first time, eye movements of acute hemianopic patients (n= 9) were recorded during the first days following stroke while they performed an exploratory visual-search task. Compared to age-matched control subjects their search duration was prolonged due to increased fixations and refixations, that is, repeated scanning of previously searched locations. Saccadic amplitudes were smaller in patients. Right hemianopic patients were more impaired than left hemianopic patients. The number of fixations and refixations did not differ significantly between both hemifields in the patients. Follow-up of one patient revealed changes of visual search over 18 months. By using more structured scanpaths with fewer saccades his search duration decreased. Furthermore, he developed a more efficient eye-movement strategy by making larger but less frequent saccades toward his blind side. In summary, visual-search behavior of acute hemianopic patients differs from healthy control subjects and from chronic hemianopic patients. We conclude that abnormal visual search in acute hemianopic patients is related to the brain lesion. We provide some evidence for adaptive eye-movement strategies developed over time. These adaptive strategies make the visual search more efficient and may help to compensate for the persisting visual-field loss. PMID:19645941

  5. Flash Flood Risk Perception in an Italian Alpine Region. From Research into Adaptive Strategies.

    NASA Astrophysics Data System (ADS)

    Scolobig, A.; de Marchi, B.; Borga, M.

    2009-04-01

    Flash floods are characterised by short lead times and high levels of uncertainty. Adaptive strategies to face them need to take into account not only the physical characteristics of the hydro-geological phenomena, but also peoples' risk perceptions, attitudes and behaviours in case of an emergency. It is quite obvious that a precondition for an effective adaptation, e.g. in the case of a warning, is the awareness of being endangered. At the same time the perceptions of those at risk and their likely actions inform hazard warning strategies and recovery programmes following such events. Usually low risk awareness or "wrong perceptions" of the residents are considered among the causes of an inadequate preparedness or response to flash floods as well as a symptom of a scarce self-protection culture. In this paper we will focus on flood risk perception and on how research on this topic may contribute to design adaptive strategies and give inputs to flood policy decisions. We will report on a flood risk perception study of the population residing in four villages in an Italian Alpine Region (Trentino Alto-Adige), carried out between October 2005 and January 2006. A total of 400 standardised questionnaires were submitted to local residents by face to face interviews. The surveys were preceded by focus groups with officers from agencies in charge of flood risk management and semi-structured and in-depth interviews with policy, scientific and technical experts. Survey results indicated that people are not so worried about hydro-geological phenomena, and think that their community is more endangered than themselves. The knowledge of the territory and danger sources, the unpredictability of flash floods and the feeling of safety induced by structural devices are the main elements which make the difference in shaping residents' perceptions. The study also demonstrated a widespread lack of adoption of preparatory measures among residents, together with a general low

  6. When climate change is a fact! Adaptive strategies for drinking water production in a changing natural environment.

    PubMed

    Meuleman, A F M; Cirkel, G; Zwolsman, G J J

    2007-01-01

    Climate change increases water system dynamics through temperature changes, changes in precipitation patterns, evaporation, and water quality and water storage in ice packs. Water system dependent economical stakeholders, such as drinking water companies in the Netherlands, have to cope with consequences of climate change, e.g. floods and water shortages in river systems, upcoming of brackish ground water, salt water intrusion, increasing peak demands and microbiological activity due to temperature rise. In the past decades, however, both water systems and drinking water production have become more and more inflexible; water systems have been heavily regulated aiming at maximum security and economic functions and the drinking water supply in the Netherlands has grown into an inflexible, but cheap and reliable, system. At a water catchment scale, flexibility and adaptation are solutions to overcome climate change related consequences. Flexible adaptive strategies for drinking water production comprise new sources for drinking water production, application of storage concepts in the short term, and a redesign of large centralized systems, including flexible treatment plants, in the long term. Transition to flexible concepts will take decades because investment depreciation periods of assets are long. These strategies must be based on thorough knowledge of current assets to seize opportunities for change.

  7. Developing Coastal Adaptation to Climate Change in the New York City Infrastructure-Shed: Process, Approach, Tools, and Strategies

    NASA Technical Reports Server (NTRS)

    Rosenzweig, Cynthia; Solecki, William D.; Blake, Reginald; Bowman, Malcolm; Faris, Craig; Gornitz, Vivien; Horton, Radley; Jacob, Klaus; LeBlanc, Alice; Leichenko, Robin; Linkin, Megan; Major, David; O'Grady, Megan; Patrick, Lesley; Sussman, Edna; Yohe, Gary; Zimmerman, Rae

    2010-01-01

    While current rates of sea level rise and associated coastal flooding in the New York City region appear to be manageable by stakeholders responsible for communications, energy, transportation, and water infrastructure, projections for sea level rise and associated flooding in the future, especially those associated with rapid icemelt of the Greenland and West Antarctic Icesheets, may be beyond the range of current capacity because an extreme event might cause flooding and inundation beyond the planning and preparedness regimes. This paper describes the comprehensive process, approach, and tools developed by the New York City Panel on Climate Change (NPCC) in conjunction with the region s stakeholders who manage its critical infrastructure, much of which lies near the coast. It presents the adaptation approach and the sea-level rise and storm projections related to coastal risks developed through the stakeholder process. Climate change adaptation planning in New York City is characterized by a multi-jurisdictional stakeholder-scientist process, state-of-the-art scientific projections and mapping, and development of adaptation strategies based on a risk-management approach.

  8. Adaptive conventional power system stabilizer based on artificial neural network

    SciTech Connect

    Kothari, M.L.; Segal, R.; Ghodki, B.K.

    1995-12-31

    This paper deals with an artificial neural network (ANN) based adaptive conventional power system stabilizer (PSS). The ANN comprises an input layer, a hidden layer and an output layer. The input vector to the ANN comprises real power (P) and reactive power (Q), while the output vector comprises optimum PSS parameters. A systematic approach for generating training set covering wide range of operating conditions, is presented. The ANN has been trained using back-propagation training algorithm. Investigations reveal that the dynamic performance of ANN based adaptive conventional PSS is quite insensitive to wide variations in loading conditions.

  9. Multi-microphone adaptive noise reduction strategies for coordinated stimulation in bilateral cochlear implant devices.

    PubMed

    Kokkinakis, Kostas; Loizou, Philipos C

    2010-05-01

    Bilateral cochlear implant (BI-CI) recipients achieve high word recognition scores in quiet listening conditions. Still, there is a substantial drop in speech recognition performance when there is reverberation and more than one interferers. BI-CI users utilize information from just two directional microphones placed on opposite sides of the head in a so-called independent stimulation mode. To enhance the ability of BI-CI users to communicate in noise, the use of two computationally inexpensive multi-microphone adaptive noise reduction strategies exploiting information simultaneously collected by the microphones associated with two behind-the-ear (BTE) processors (one per ear) is proposed. To this end, as many as four microphones are employed (two omni-directional and two directional) in each of the two BTE processors (one per ear). In the proposed two-microphone binaural strategies, all four microphones (two behind each ear) are being used in a coordinated stimulation mode. The hypothesis is that such strategies combine spatial information from all microphones to form a better representation of the target than that made available with only a single input. Speech intelligibility is assessed in BI-CI listeners using IEEE sentences corrupted by up to three steady speech-shaped noise sources. Results indicate that multi-microphone strategies improve speech understanding in single- and multi-noise source scenarios.

  10. An adaptive time-stepping strategy for solving the phase field crystal model

    SciTech Connect

    Zhang, Zhengru; Ma, Yuan; Qiao, Zhonghua

    2013-09-15

    In this work, we will propose an adaptive time step method for simulating the dynamics of the phase field crystal (PFC) model. The numerical simulation of the PFC model needs long time to reach steady state, and then large time-stepping method is necessary. Unconditionally energy stable schemes are used to solve the PFC model. The time steps are adaptively determined based on the time derivative of the corresponding energy. It is found that the use of the proposed time step adaptivity cannot only resolve the steady state solution, but also the dynamical development of the solution efficiently and accurately. The numerical experiments demonstrate that the CPU time is significantly saved for long time simulations.

  11. A new strategy for exploring the hierarchical structure of cancers by adaptively partitioning functional modules from gene expression network

    PubMed Central

    Xu, Junmei; Jing, Runyu; Liu, Yuan; Dong, Yongcheng; Wen, Zhining; Li, Menglong

    2016-01-01

    The interactions among the genes within a disease are helpful for better understanding the hierarchical structure of the complex biological system of it. Most of the current methodologies need the information of known interactions between genes or proteins to create the network connections. However, these methods meet the limitations in clinical cancer researches because different cancers not only share the common interactions among the genes but also own their specific interactions distinguished from each other. Moreover, it is still difficult to decide the boundaries of the sub-networks. Therefore, we proposed a strategy to construct a gene network by using the sparse inverse covariance matrix of gene expression data, and divide it into a series of functional modules by an adaptive partition algorithm. The strategy was validated by using the microarray data of three cancers and the RNA-sequencing data of glioblastoma. The different modules in the network exhibited specific functions in cancers progression. Moreover, based on the gene expression profiles in the modules, the risk of death was well predicted in the clustering analysis and the binary classification, indicating that our strategy can be benefit for investigating the cancer mechanisms and promoting the clinical applications of network-based methodologies in cancer researches. PMID:27349736

  12. The impact of climate change on grain maize production over Europe - adaptation with different irrigation strategies

    NASA Astrophysics Data System (ADS)

    Ceglar, A.; Srivastava, A. K.; Chukaliev, O.; Duveiller, G.; Niemeyer, S.

    2013-12-01

    The spatial distribution of water deficit and maize yield deficit across Europe has been compared between current and expected climatic conditions in the near future (time window 2030). Maize yields and water requirements were simulated using the WOFOST (World Food Studies) crop growth model. In our study, the priority has been given to future projections of the A1B emission scenario produced within the ENSEMBLE project: HadRM3 RCM nested within the HADCM3 GCM (HADLEY) and HIRHAM5 RCM nested within ECHAM5 GCM (ECHAM). The two realizations can be considered as warm (HADLEY) and cold (ECHAM5) according to simulated temperature in the near future and therefore represent the extremes in air temperature change within those analyzed in ENSEMBLES project, allowing us to evaluate the largest range of uncertainty in weather inputs to the impact model. In addition, we also explored the advantages of different irrigation strategies for the target crop to offset climate change impacts. In wake of limited amount of water availability for agriculture purposes, we explored effectiveness of three different irrigation strategies on maize yield over Europe, namely full, deficit and supplemental irrigation. The results of our study indicate that the maize yield under rainfed conditions is expected to decrease over the Southern Europe as well as regions around the Black Sea during the 2030s under both climate model realizations. Water deficit is expected to increase especially in the Mediterranean, whereas slightly less in parts of Central and Western Europe. However, adaptation strategies followed in this study negate the detrimental effect of climate change and result in an increased maize yield. Three irrigation strategies have been simulated differing in timing of water application and in the total volume of water supplied during the growing season. The results show that yields, achieved using deficit and full irrigation strategies, are not significantly different. Hence, at least

  13. Using a Multicomponent Adapted Power Card Strategy to Decrease Latency during Interactivity Transitions for Three Children with Developmental Disabilities

    ERIC Educational Resources Information Center

    Angell, Maureen E.; Nicholson, Joanna K.; Watts, Emily H.; Blum, Craig

    2011-01-01

    An adapted Power Card strategy was examined to determine effectiveness in decreasing latency in responding to teacher cues to initiate interactivity transitions in the classroom among three students, aged 10 to 11 years, with developmental disabilities (i.e., one with autism and two with intellectual disability). The Power Card strategy, a form of…

  14. Adaptive mechanism-based congestion control for networked systems

    NASA Astrophysics Data System (ADS)

    Liu, Zhi; Zhang, Yun; Chen, C. L. Philip

    2013-03-01

    In order to assure the communication quality in network systems with heavy traffic and limited bandwidth, a new ATRED (adaptive thresholds random early detection) congestion control algorithm is proposed for the congestion avoidance and resource management of network systems. Different to the traditional AQM (active queue management) algorithms, the control parameters of ATRED are not configured statically, but dynamically adjusted by the adaptive mechanism. By integrating with the adaptive strategy, ATRED alleviates the tuning difficulty of RED (random early detection) and shows a better control on the queue management, and achieve a more robust performance than RED under varying network conditions. Furthermore, a dynamic transmission control protocol-AQM control system using ATRED controller is introduced for the systematic analysis. It is proved that the stability of the network system can be guaranteed when the adaptive mechanism is finely designed. Simulation studies show the proposed ATRED algorithm achieves a good performance in varying network environments, which is superior to the RED and Gentle-RED algorithm, and providing more reliable service under varying network conditions.

  15. Adaptive step-size strategy for noise-robust Fourier ptychographic microscopy.

    PubMed

    Zuo, Chao; Sun, Jiasong; Chen, Qian

    2016-09-01

    The incremental gradient approaches, such as PIE and ePIE, are widely used in the field of ptychographic imaging due to their great flexibility and computational efficiency. Nevertheless, their stability and reconstruction quality may be significantly degraded when non-negligible noise is present in the image. Though this problem is often attributed to the non-convex nature of phase retrieval, we found the reason for this is more closely related to the choice of the step-size, which needs to be gradually diminishing for convergence even in the convex case. To this end, we introduce an adaptive step-size strategy that decreases the step-size whenever sufficient progress is not made. The synthetic and real experiments on Fourier ptychographic microscopy show that the adaptive step-size strategy significantly improves the stability and robustness of the reconstruction towards noise yet retains the fast initial convergence speed of PIE and ePIE. More importantly, the proposed approach is simple, nonparametric, and does not require any preknowledge about the noise statistics. The great performance and limited computational complexity make it a very attractive and promising technique for robust Fourier ptychographic microscopy under noisy conditions. PMID:27607676

  16. Flood risk and adaptation strategies in Indonesia: a probabilistic analysis using globally available data

    NASA Astrophysics Data System (ADS)

    Muis, Sanne; Güneralp, Burak; Jongman, Brenden; Aerts, Jeroen; Ward, Philip

    2015-04-01

    In recent years, global flood losses are increasing due to socio-economic development and climate change, with the largest risk increases in developing countries such as Indonesia. For countries to undertake effective risk-management, an accurate understanding of both current and future risk is required. However, detailed information is rarely available, particularly for developing countries. We present a first of its kind country-scale analysis of flood risk using globally available data that combines a global inundation model with a land use change model and more local data on flood damages. To assess the contribution and uncertainty of different drivers of future risk, we integrate thousands of socio-economic and climate projections in a probabilistic way and include multiple adaptation strategies. Indonesia is used as a case-study as it a country that already faces high flood risk, and is undergoing rapid urbanization. We developed probabilistic and spatially-explicit urban expansion projections from 2000 to 2030 that show that the increase in urban extent ranges from 215% to 357% (5th and 95th percentile). We project rapidly rising flood risk, both for coastal and river floods. This increase is largely driven by economic growth and urban expansion (i.e. increasing exposure). Whilst sea level rise will amply this trend, the response of river floods to climate change is uncertain with the impact of the mean ensemble of 20 climate projections (5 GCMs and 4 RCPs) being close to zero. However, as urban expansion is the main driving force of future risk, we argue that the implementation of adaptation measures is increasingly pressing, regardless of the wide uncertainty in climate projections. Hence, we evaluated the effectiveness of two adaptation measures: spatial planning in flood prone areas and enhanced flood protection. Both strategies have a large potential to effectively offset the increasing risk trend. The risk reduction is in the range of 22-85% and 53

  17. Lethal aggression in Pan is better explained by adaptive strategies than human impacts.

    PubMed

    Wilson, Michael L; Boesch, Christophe; Fruth, Barbara; Furuichi, Takeshi; Gilby, Ian C; Hashimoto, Chie; Hobaiter, Catherine L; Hohmann, Gottfried; Itoh, Noriko; Koops, Kathelijne; Lloyd, Julia N; Matsuzawa, Tetsuro; Mitani, John C; Mjungu, Deus C; Morgan, David; Muller, Martin N; Mundry, Roger; Nakamura, Michio; Pruetz, Jill; Pusey, Anne E; Riedel, Julia; Sanz, Crickette; Schel, Anne M; Simmons, Nicole; Waller, Michel; Watts, David P; White, Frances; Wittig, Roman M; Zuberbühler, Klaus; Wrangham, Richard W

    2014-09-18

    Observations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) provide valuable comparative data for understanding the significance of conspecific killing. Two kinds of hypothesis have been proposed. Lethal violence is sometimes concluded to be the result of adaptive strategies, such that killers ultimately gain fitness benefits by increasing their access to resources such as food or mates. Alternatively, it could be a non-adaptive result of human impacts, such as habitat change or food provisioning. To discriminate between these hypotheses we compiled information from 18 chimpanzee communities and 4 bonobo communities studied over five decades. Our data include 152 killings (n = 58 observed, 41 inferred, and 53 suspected killings) by chimpanzees in 15 communities and one suspected killing by bonobos. We found that males were the most frequent attackers (92% of participants) and victims (73%); most killings (66%) involved intercommunity attacks; and attackers greatly outnumbered their victims (median 8:1 ratio). Variation in killing rates was unrelated to measures of human impacts. Our results are compatible with previously proposed adaptive explanations for killing by chimpanzees, whereas the human impact hypothesis is not supported. PMID:25230664

  18. Lethal aggression in Pan is better explained by adaptive strategies than human impacts.

    PubMed

    Wilson, Michael L; Boesch, Christophe; Fruth, Barbara; Furuichi, Takeshi; Gilby, Ian C; Hashimoto, Chie; Hobaiter, Catherine L; Hohmann, Gottfried; Itoh, Noriko; Koops, Kathelijne; Lloyd, Julia N; Matsuzawa, Tetsuro; Mitani, John C; Mjungu, Deus C; Morgan, David; Muller, Martin N; Mundry, Roger; Nakamura, Michio; Pruetz, Jill; Pusey, Anne E; Riedel, Julia; Sanz, Crickette; Schel, Anne M; Simmons, Nicole; Waller, Michel; Watts, David P; White, Frances; Wittig, Roman M; Zuberbühler, Klaus; Wrangham, Richard W

    2014-09-18

    Observations of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) provide valuable comparative data for understanding the significance of conspecific killing. Two kinds of hypothesis have been proposed. Lethal violence is sometimes concluded to be the result of adaptive strategies, such that killers ultimately gain fitness benefits by increasing their access to resources such as food or mates. Alternatively, it could be a non-adaptive result of human impacts, such as habitat change or food provisioning. To discriminate between these hypotheses we compiled information from 18 chimpanzee communities and 4 bonobo communities studied over five decades. Our data include 152 killings (n = 58 observed, 41 inferred, and 53 suspected killings) by chimpanzees in 15 communities and one suspected killing by bonobos. We found that males were the most frequent attackers (92% of participants) and victims (73%); most killings (66%) involved intercommunity attacks; and attackers greatly outnumbered their victims (median 8:1 ratio). Variation in killing rates was unrelated to measures of human impacts. Our results are compatible with previously proposed adaptive explanations for killing by chimpanzees, whereas the human impact hypothesis is not supported.

  19. Adaptive Benefits of Storage Strategy and Dual AMPK/TOR Signaling in Metabolic Stress Response

    PubMed Central

    Pfeuty, Benjamin; Thommen, Quentin

    2016-01-01

    Cellular metabolism must ensure that supply of nutrient meets the biosynthetic and bioenergetic needs. Cells have therefore developed sophisticated signaling and regulatory pathways in order to cope with dynamic fluctuations of both resource and demand and to regulate accordingly diverse anabolic and catabolic processes. Intriguingly, these pathways are organized around a relatively small number of regulatory hubs, such as the highly conserved AMPK and TOR kinase families in eukaryotic cells. Here, the global metabolic adaptations upon dynamic environment are investigated using a prototypical model of regulated metabolism. In this model, the optimal enzyme profiles as well as the underlying regulatory architecture are identified by combining perturbation and evolutionary methods. The results reveal the existence of distinct classes of adaptive strategies, which differ in the management of storage reserve depending on the intensity of the stress and in the regulation of ATP-producing reaction depending on the nature of the stress. The regulatory architecture that optimally implements these adaptive features is characterized by a crosstalk between two specialized signaling pathways, which bears close similarities with the sensing and regulatory properties of AMPK and TOR pathways. PMID:27505075

  20. Adaptive Benefits of Storage Strategy and Dual AMPK/TOR Signaling in Metabolic Stress Response.

    PubMed

    Pfeuty, Benjamin; Thommen, Quentin

    2016-01-01

    Cellular metabolism must ensure that supply of nutrient meets the biosynthetic and bioenergetic needs. Cells have therefore developed sophisticated signaling and regulatory pathways in order to cope with dynamic fluctuations of both resource and demand and to regulate accordingly diverse anabolic and catabolic processes. Intriguingly, these pathways are organized around a relatively small number of regulatory hubs, such as the highly conserved AMPK and TOR kinase families in eukaryotic cells. Here, the global metabolic adaptations upon dynamic environment are investigated using a prototypical model of regulated metabolism. In this model, the optimal enzyme profiles as well as the underlying regulatory architecture are identified by combining perturbation and evolutionary methods. The results reveal the existence of distinct classes of adaptive strategies, which differ in the management of storage reserve depending on the intensity of the stress and in the regulation of ATP-producing reaction depending on the nature of the stress. The regulatory architecture that optimally implements these adaptive features is characterized by a crosstalk between two specialized signaling pathways, which bears close similarities with the sensing and regulatory properties of AMPK and TOR pathways. PMID:27505075

  1. Exoskeleton control for lower-extremity assistance based on adaptive frequency oscillators: adaptation of muscle activation and movement frequency.

    PubMed

    Aguirre-Ollinger, Gabriel

    2015-01-01

    In this article, we analyze a novel strategy for assisting the lower extremities based on adaptive frequency oscillators. Our aim is to use the control algorithm presented here as a building block for the control of powered lower-limb exoskeletons. The algorithm assists cyclic movements of the human extremities by synchronizing actuator torques with the estimated net torque exerted by the muscles. Synchronization is produced by a nonlinear dynamical system combining an adaptive frequency oscillator with a form of adaptive Fourier analysis. The system extracts, in real time, the fundamental frequency component of the net muscle torque acting on a specific joint. Said component, nearly sinusoidal in shape, is the basis for the assistive torque waveform delivered by the exoskeleton. The action of the exoskeleton can be interpreted as a virtual reduction in the mechanical impedance of the leg. We studied the ability of human subjects to adapt their muscle activation to the assistive torque. Ten subjects swung their extended leg while coupled to a stationary hip joint exoskeleton. The experiment yielded a significant decrease, with respect to unassisted movement, of the activation levels of an agonist/antagonist pair of muscles controlling the hip joint's motion, which suggests the exoskeleton control has potential for assisting human gait. A moderate increase in swing frequency was observed as well. We theorize that the increase in frequency can be explained by the impedance model of the assisted leg. Per this model, subjects adjust their swing frequency in order to control the amount of reduction in net muscle torque.

  2. Exoskeleton control for lower-extremity assistance based on adaptive frequency oscillators: adaptation of muscle activation and movement frequency.

    PubMed

    Aguirre-Ollinger, Gabriel

    2015-01-01

    In this article, we analyze a novel strategy for assisting the lower extremities based on adaptive frequency oscillators. Our aim is to use the control algorithm presented here as a building block for the control of powered lower-limb exoskeletons. The algorithm assists cyclic movements of the human extremities by synchronizing actuator torques with the estimated net torque exerted by the muscles. Synchronization is produced by a nonlinear dynamical system combining an adaptive frequency oscillator with a form of adaptive Fourier analysis. The system extracts, in real time, the fundamental frequency component of the net muscle torque acting on a specific joint. Said component, nearly sinusoidal in shape, is the basis for the assistive torque waveform delivered by the exoskeleton. The action of the exoskeleton can be interpreted as a virtual reduction in the mechanical impedance of the leg. We studied the ability of human subjects to adapt their muscle activation to the assistive torque. Ten subjects swung their extended leg while coupled to a stationary hip joint exoskeleton. The experiment yielded a significant decrease, with respect to unassisted movement, of the activation levels of an agonist/antagonist pair of muscles controlling the hip joint's motion, which suggests the exoskeleton control has potential for assisting human gait. A moderate increase in swing frequency was observed as well. We theorize that the increase in frequency can be explained by the impedance model of the assisted leg. Per this model, subjects adjust their swing frequency in order to control the amount of reduction in net muscle torque. PMID:25655955

  3. Video Adaptation Model Based on Cognitive Lattice in Ubiquitous Computing

    NASA Astrophysics Data System (ADS)

    Kim, Svetlana; Yoon, Yong-Ik

    The multimedia service delivery chain poses today many challenges. There are an increasing terminal diversity, network heterogeneity and a pressure to satisfy the user preferences. The situation encourages the need for the personalized contents to provide the user in the best possible experience in ubiquitous computing. This paper introduces a personalized content preparation and delivery framework for multimedia service. The personalized video adaptation is expected to satisfy individual users' need in video content. Cognitive lattice plays a significant role of video annotation to meet users' preference on video content. In this paper, a comprehensive solution for the PVA (Personalized Video Adaptation) is proposed based on Cognitive lattice concept. The PVA is implemented based on MPEG-21 Digital Item Adaptation framework. One of the challenges is how to quantify users' preference on video content.

  4. Design of an adaptive neural network based power system stabilizer.

    PubMed

    Liu, Wenxin; Venayagamoorthy, Ganesh K; Wunsch, Donald C

    2003-01-01

    Power system stabilizers (PSS) are used to generate supplementary control signals for the excitation system in order to damp the low frequency power system oscillations. To overcome the drawbacks of conventional PSS (CPSS), numerous techniques have been proposed in the literature. Based on the analysis of existing techniques, this paper presents an indirect adaptive neural network based power system stabilizer (IDNC) design. The proposed IDNC consists of a neuro-controller, which is used to generate a supplementary control signal to the excitation system, and a neuro-identifier, which is used to model the dynamics of the power system and to adapt the neuro-controller parameters. The proposed method has the features of a simple structure, adaptivity and fast response. The proposed IDNC is evaluated on a single machine infinite bus power system under different operating conditions and disturbances to demonstrate its effectiveness and robustness. PMID:12850048

  5. Developing the evidence base for mainstreaming adaptation of stormwater systems to climate change.

    PubMed

    Gersonius, B; Nasruddin, F; Ashley, R; Jeuken, A; Pathirana, A; Zevenbergen, C

    2012-12-15

    In a context of high uncertainty about hydro-climatic variables, the development of updated methods for climate impact and adaptation assessment is as important, if not more important than the provision of improved climate change data. In this paper, we introduce a hybrid method to facilitate mainstreaming adaptation of stormwater systems to climate change: i.e., the Mainstreaming method. The Mainstreaming method starts with an analysis of adaptation tipping points (ATPs), which is effect-based. These are points of reference where the magnitude of climate change is such that acceptable technical, environmental, societal or economic standards may be compromised. It extends the ATP analysis to include aspects from a bottom-up approach. The extension concerns the analysis of adaptation opportunities in the stormwater system. The results from both analyses are then used in combination to identify and exploit Adaptation Mainstreaming Moments (AMMs). Use of this method will enhance the understanding of the adaptive potential of stormwater systems. We have applied the proposed hybrid method to the management of flood risk for an urban stormwater system in Dordrecht (the Netherlands). The main finding of this case study is that the application of the Mainstreaming method helps to increase the no-/low-regret character of adaptation for several reasons: it focuses the attention on the most urgent effects of climate change; it is expected to lead to potential cost reductions, since adaptation options can be integrated into infrastructure and building design at an early stage instead of being applied separately; it will lead to the development of area-specific responses, which could not have been developed on a higher scale level; it makes it possible to take account of local values and sensibilities, which contributes to increased public and political support for the adaptive strategies.

  6. A Functional Approach To Uncover the Low-Temperature Adaptation Strategies of the Archaeon Methanosarcina barkeri

    PubMed Central

    McCay, Paul; Fuszard, Matthew; Botting, Catherine H.; Abram, Florence; O'Flaherty, Vincent

    2013-01-01

    Low-temperature anaerobic digestion (LTAD) technology is underpinned by a diverse microbial community. The methanogenic archaea represent a key functional group in these consortia, undertaking CO2 reduction as well as acetate and methylated C1 metabolism with subsequent biogas (40 to 60% CH4 and 30 to 50% CO2) formation. However, the cold adaptation strategies, which allow methanogens to function efficiently in LTAD, remain unclear. Here, a pure-culture proteomic approach was employed to study the functional characteristics of Methanosarcina barkeri (optimum growth temperature, 37°C), which has been detected in LTAD bioreactors. Two experimental approaches were undertaken. The first approach aimed to characterize a low-temperature shock response (LTSR) of M. barkeri DSMZ 800T grown at 37°C with a temperature drop to 15°C, while the second experimental approach aimed to examine the low-temperature adaptation strategies (LTAS) of the same strain when it was grown at 15°C. The latter experiment employed cell viability and growth measurements (optical density at 600 nm [OD600]), which directly compared M. barkeri cells grown at 15°C with those grown at 37°C. During the LTSR experiment, a total of 127 proteins were detected in 37°C and 15°C samples, with 20 proteins differentially expressed with respect to temperature, while in the LTAS experiment 39% of proteins identified were differentially expressed between phases of growth. Functional categories included methanogenesis, cellular information processing, and chaperones. By applying a polyphasic approach (proteomics and growth studies), insights into the low-temperature adaptation capacity of this mesophilically characterized methanogen were obtained which suggest that the metabolically diverse Methanosarcinaceae could be functionally relevant for LTAD systems. PMID:23645201

  7. Therapeutic strategies based on polymeric microparticles.

    PubMed

    Vilos, C; Velasquez, L A

    2012-01-01

    The development of the field of materials science, the ability to perform multidisciplinary scientific work, and the need for novel administration technologies that maximize therapeutic effects and minimize adverse reactions to readily available drugs have led to the development of delivery systems based on microencapsulation, which has taken one step closer to the target of personalized medicine. Drug delivery systems based on polymeric microparticles are generating a strong impact on preclinical and clinical drug development and have reached a broad development in different fields supporting a critical role in the near future of medical practice. This paper presents the foundations of polymeric microparticles based on their formulation, mechanisms of drug release and some of their innovative therapeutic strategies to board multiple diseases.

  8. Adaptive reconnection-based arbitrary Lagrangian Eulerian method

    NASA Astrophysics Data System (ADS)

    Bo, Wurigen; Shashkov, Mikhail

    2015-10-01

    eW present a new adaptive Arbitrary Lagrangian Eulerian (ALE) method. This method is based on the reconnection-based ALE (ReALE) methodology of Refs. [35,34,6]. The main elements in a standard ReALE method are: an explicit Lagrangian phase on an arbitrary polygonal (in 2D) mesh in which the solution and positions of grid nodes are updated; a rezoning phase in which a new grid is defined by changing the connectivity (using Voronoi tessellation) but not the number of cells; and a remapping phase in which the Lagrangian solution is transferred onto the new grid. In the standard ReALE method, the rezoned mesh is smoothed by using one or several steps toward centroidal Voronoi tessellation, but it is not adapted to the solution in any way. In the current paper we present a new adaptive ReALE method, A-ReALE, that is based on the following design principles. First, a monitor function (or error indicator) based on the Hessian of some flow parameter(s) is utilized. Second, an equi-distribution principle for the monitor function is used as a criterion for adapting the mesh. Third, a centroidal Voronoi tessellation is used to adapt the mesh. Fourth, we scale the monitor function to avoid very small and large cells and then smooth it to permit the use of theoretical results related to weighted centroidal Voronoi tessellation. In the A-ReALE method, both number of cells and their locations are allowed to change at the rezone stage on each time step. The number of generators at each time step is chosen to guarantee the required spatial resolution in regions where monitor function reaches its maximum value. We present all details required for implementation of new adaptive A-ReALE method and demonstrate its performance in comparison with standard ReALE method on series of numerical examples.

  9. Empirically Based Strategies for Preventing Juvenile Delinquency.

    PubMed

    Pardini, Dustin

    2016-04-01

    Juvenile crime is a serious public health problem that results in significant emotional and financial costs for victims and society. Using etiologic models as a guide, multiple interventions have been developed to target risk factors thought to perpetuate the emergence and persistence of delinquent behavior. Evidence suggests that the most effective interventions tend to have well-defined treatment protocols, focus on therapeutic approaches as opposed to external control techniques, and use multimodal cognitive-behavioral treatment strategies. Moving forward, there is a need to develop effective policies and procedures that promote the widespread adoption of evidence-based delinquency prevention practices across multiple settings. PMID:26980128

  10. A geometry-based adaptive unstructured grid generation algorithm for complex geological media

    NASA Astrophysics Data System (ADS)

    Bahrainian, Seyed Saied; Dezfuli, Alireza Daneh

    2014-07-01

    In this paper a novel unstructured grid generation algorithm is presented that considers the effect of geological features and well locations in grid resolution. The proposed grid generation algorithm presents a strategy for definition and construction of an initial grid based on the geological model, geometry adaptation of geological features, and grid resolution control. The algorithm is applied to seismotectonic map of the Masjed-i-Soleiman reservoir. Comparison of grid results with the “Triangle” program shows a more suitable permeability contrast. Immiscible two-phase flow solutions are presented for a fractured porous media test case using different grid resolutions. Adapted grid on the fracture geometry gave identical results with that of a fine grid. The adapted grid employed 88.2% less CPU time when compared to the solutions obtained by the fine grid.

  11. Effect of adaptation strategies when feeding fresh cassava foliage on intake and physiological responses of lambs.

    PubMed

    Hue, Khuc Thi; Van, Do Thi Thanh; Spörndly, Eva; Ledin, Inger; Wredle, Ewa

    2012-02-01

    The objective of the experiment was to study different adaptation strategies to avoid HCN intoxication when feeding fresh cassava foliage to sheep. Twenty-four Phan Rang lambs (initial weight = 19.6 kg at 5.5 months of age) were used in the study. The four experimental diets contained guinea grass (Panicum maximum) supplemented with concentrate at 1.5% of body weight (BW) as dry matter (DM) (control) or supplemented with fresh cassava foliage (FCF) that was introduced into the diet with an adaptation period of 0 (FCF-0), 7 (FCF-7) or 21 (FCF-21) days before reaching the target feeding level of 2% of BW. The average intake of FCF expressed as DM was not different amongst the supplemented treatments and ranged from 1.4 to 1.5% of BW but gradually increased during the first 7 days without any adaptation. The hydrogen cyanide consumed varied from 5.1 to 5.4 mg/kg BW and no difference between treatments with cassava foliage in the diet was found. The live weight gain was significantly higher in the treatments control and FCF-7 compared to FCF-21. No significant differences in heart rate, respiration rate and rumen movement were found between diets. The thiocyanate concentration in the urine of the lambs increased concomitantly with the increase in fresh cassava foliage offered during the first part of the experiment. In conclusion, an adaptation period of approximately 7 days seems to be favourable in combined diets where cassava foliage is offered in quantities up to 2% of BW. This level of intake could enhance the intake and LWG of the lambs without any documented effects on heart rate, respiration rate or rumen movements.

  12. Water Reserves Program. An adaptation strategy to prevent imbalance of water in nature

    NASA Astrophysics Data System (ADS)

    Salinas-Rodriguez, S. A.; López Pérez, M.; Barrios Ordóñez, J.; Wickel, B.; Villón Bracamonte, R. A.

    2013-12-01

    allocated, and where the flow regime is then protected before over-allocation takes place. The strategy has been to identify and protect basins with an availability of water that is close to their natural flow regime and that also have a high conservation value (based on prior national conservation priority definitions such as protected areas, and biodiversity conservation gap analyses) in order to implement legal restrictions on water resource development. With such protection, these systems will be best positioned to adjust and respond to water shortages, and regime shifts. To date, 189 basins around the country were identified as potential water reserves. The next step will be the nomination of these water reserves to be integrated in the National Water Reserves Program. This program forms the core of the official Mexican government adaptation strategy towards climate prepared water management, which recognizes that water reserves are the buffer society needs to face uncertainty, imbalance of the man-made, global changes, and thus to reduce water scarcity risk. The development of activities that alter the natural flow regime such as dams and levees are closely examined, and would potentially be restricted.

  13. Water Reserves Program. An adaptation strategy to balance water in nature

    NASA Astrophysics Data System (ADS)

    Lopez Perez, M.; Barrios, E.; Salinas-Rodriguez, S.; Wickel, B.; Villon, R. A.

    2013-05-01

    -allocation takes place. The strategy is to identify and protect basins with an availability of water that is close to their natural flow regime and that also have a high conservation value (based on prior national conservation priority definitions such as protected areas, and biodiversity conservation gap analyses) in order to implement legal restrictions on water resource development. With such protection, these systems will be best positioned to adjust and respond to water shortages, and regime shifts. To date, 189 basins around the country were identified as potential water reserves. The next step will be the nomination of these water reserves to be integrated in the National Water Reserves Program. This program forms the core of the official Mexican government adaptation strategy towards climate prepared water management, which recognizes that water reserves are the buffer society needs to face uncertainty, and reduce water scarcity risk. The development of activities that alter the natural flow regime such as dams and levees are closely examined, and would potentially be restricted.

  14. The QoE implications of ultra-high definition video adaptation strategies

    NASA Astrophysics Data System (ADS)

    Nightingale, James; Awobuluyi, Olatunde; Wang, Qi; Alcaraz-Calero, Jose M.; Grecos, Christos

    2016-04-01

    As the capabilities of high-end consumer devices increase, streaming and playback of Ultra-High Definition (UHD) is set to become commonplace. The move to these new, higher resolution, video services is one of the main factors contributing to the predicted continuation of growth in video related traffic in the Internet. This massive increases in bandwidth requirement, even when mitigated by the use of new video compression standards such as H.265, will place an ever-increasing burden on network service providers. This will be especially true in mobile environments where users have come to expect ubiquitous access to content. Consequently, delivering UHD and Full UHD (FUHD) video content is one of the key drivers for future Fifth Generation (5G) mobile networks. One often voiced, but as yet unanswered question, is whether users of mobile devices with modest screen sizes (e.g. smartphones or smaller tablet) will actually benefit from consuming the much higher bandwidth required to watch online UHD video, in terms of an improved user experience. In this paper, we use scalable H.265 encoded video streams to conduct a subjective evaluation of the impact on a user's perception of video quality across a comprehensive range of adaptation strategies, covering each of the three adaptation domains, for UHD and FUHD video. The results of our subjective study provide insightful and useful indications of which methods of adapting UHD and FUHD streams have the least impact on user's perceived QoE. In particular, it was observed that, in over 70% of cases, users were unable to distinguish between full HD (1080p) and UHD (4K) videos when they were unaware of which version was being shown to them. Our results from this evaluation can be used to provide adaptation rule sets that will facilitate fast, QoE aware in-network adaptation of video streams in support of realtime adaptation objectives. Undoubtedly they will also promote discussion around how network service providers manage

  15. Profiling Students' Adaptation Styles in Web-based Learning.

    ERIC Educational Resources Information Center

    Lee, Myung-Geun

    2001-01-01

    Discussion of Web-based instruction (WBI) focuses on a study of Korean universities that analyzed learners' adaptation styles and characteristics by retrospectively assessing the perceptions of various aspects of WBI. Considers computer literacy, interaction with instructor and students, difficulty of contents, and learners' perception of academic…

  16. Adaptive NUC algorithm for uncooled IRFPA based on neural networks

    NASA Astrophysics Data System (ADS)

    Liu, Ziji; Jiang, Yadong; Lv, Jian; Zhu, Hongbin

    2010-10-01

    With developments in uncooled infrared plane array (UFPA) technology, many new advanced uncooled infrared sensors are used in defensive weapons, scientific research, industry and commercial applications. A major difference in imaging techniques between infrared IRFPA imaging system and a visible CCD camera is that, IRFPA need nonuniformity correction and dead pixel compensation, we usually called it infrared image pre-processing. Two-point or multi-point correction algorithms based on calibration commonly used may correct the non-uniformity of IRFPAs, but they are limited by pixel linearity and instability. Therefore, adaptive non-uniformity correction techniques are developed. Two of these adaptive non-uniformity correction algorithms are mostly discussed, one is based on temporal high-pass filter, and another is based on neural network. In this paper, a new NUC algorithm based on improved neural networks is introduced, and involves the compare result between improved neural networks and other adaptive correction techniques. A lot of different will discussed in different angle, like correction effects, calculation efficiency, hardware implementation and so on. According to the result and discussion, it could be concluding that the adaptive algorithm offers improved performance compared to traditional calibration mode techniques. This new algorithm not only provides better sensitivity, but also increases the system dynamic range. As the sensor application expended, it will be very useful in future infrared imaging systems.

  17. Adaptive Knowledge Management of Project-Based Learning

    ERIC Educational Resources Information Center

    Tilchin, Oleg; Kittany, Mohamed

    2016-01-01

    The goal of an approach to Adaptive Knowledge Management (AKM) of project-based learning (PBL) is to intensify subject study through guiding, inducing, and facilitating development knowledge, accountability skills, and collaborative skills of students. Knowledge development is attained by knowledge acquisition, knowledge sharing, and knowledge…

  18. Teaching a Biotechnology Curriculum Based on Adapted Primary Literature

    ERIC Educational Resources Information Center

    Falk, Hedda; Brill, Gilat; Yarden, Anat

    2008-01-01

    Adapted primary literature (APL) refers to an educational genre specifically designed to enable the use of research articles for learning biology in high school. The present investigation focuses on the pedagogical content knowledge (PCK) of four high-school biology teachers who enacted an APL-based curriculum in biotechnology. Using a…

  19. An Adaptive Evaluation Structure for Computer-Based Instruction.

    ERIC Educational Resources Information Center

    Welsh, William A.

    Adaptive Evaluation Structure (AES) is a set of linked computer programs designed to increase the effectiveness of interactive computer-assisted instruction at the college level. The package has four major features, the first of which is based on a prior cognitive inventory and on the accuracy and pace of student responses. AES adjusts materials…

  20. Evidence-Based Practice in Adapted Physical Education

    ERIC Educational Resources Information Center

    Jin, Jooyeon; Yun, Joonkoo

    2010-01-01

    Although implementation of evidence-based practice (EBP) has been strongly advocated by federal legislation as well as school districts in recent years, the concept has not been well accepted in adapted physical education (APE), perhaps due to a lack of understanding of the central notion of EBP. The purpose of this article is to discuss how APE…

  1. Future tendencies of climate indicators important for adaptation and mitigation strategies in forestry

    NASA Astrophysics Data System (ADS)

    Galos, Borbala; Hänsler, Andreas; Gulyas, Krisztina; Bidlo, Andras; Czimber, Kornel

    2014-05-01

    impact analyses and build an important basis of the future adaptation strategies in forestry, agriculture and water management. Funding: The research is supported by the TÁMOP-4.2.2.A-11/1/KONV-2012-0013 and TÁMOP-4.1.1.C-12/1/KONV-2012-0012 (ZENFE) joint EU-national research projects. Keywords: climate indices, climate change impacts, forestry, regional climate modelling

  2. Renewable energy to develop adaptation strategies to the climate change conditions

    NASA Astrophysics Data System (ADS)

    Servadio, Pieranna; Bergonzoli, Simone

    2013-04-01

    Changes in land use and combustion of fossil fuels have been largest human impact on the global carbon cycle and without a complete accounting of net greenhouse-gas (GHG) fluxes, developing and evaluating adaptation strategies are not possible. The major source of GHG fluxes associated with crop production are soil N2O emissions, soil CO2 and methane (CH4) fluxes, and CO2 emission associated with agricultural inputs and farm equipment operation. This study points out the main principles which are at the base of solar energy use for sustainability of irrigated agriculture. Field tests were carried out in order to compare crop yield and solar pump plant performance, for the photovoltaic conversion of solar energy, connected to drip irrigation and sprinkler system plants during the irrigation season. The system mainly consists of the parts listed here: set of flat photovoltaic panels consisting of 150 panels for a total of 3000 W peak value once installed, connected in serial-parallel to obtain a 120 Vdc operating voltage rating. The panels utilize 36 serially connected single-crystal silicon cells providing a 12 V voltage rating. The serial connection of 10 panels generates the system's operating voltage rating (120 Vdc). The total 3000 W peak value power is obtained by connecting in parallel 15 serial-strings. When the circuit is open, the voltage at the ends of the panels can reach 210 Volts. The photovoltaic system supplies, through an inverter, a three-phase 1.6 kW canned pump located in the artesian well. The relevant hydraulic line connects this pump to the various utilities. The hydraulic capacity of the helium pump has been used during the irrigation season in order to meet the water needs of a corn crop. Therefore, along with the solar pump was used a dispersing wing type drip irrigation system with double chamber hosing (70 kPa operating pressure), with external holes spaced 0.3 m apart, 0.75 m distance between the wings, wing length 120 m and placed

  3. Adaptive Semantic and Social Web-based learning and assessment environment for the STEM

    NASA Astrophysics Data System (ADS)

    Babaie, Hassan; Atchison, Chris; Sunderraman, Rajshekhar

    2014-05-01

    We are building a cloud- and Semantic Web-based personalized, adaptive learning environment for the STEM fields that integrates and leverages Social Web technologies to allow instructors and authors of learning material to collaborate in semi-automatic development and update of their common domain and task ontologies and building their learning resources. The semi-automatic ontology learning and development minimize issues related to the design and maintenance of domain ontologies by knowledge engineers who do not have any knowledge of the domain. The social web component of the personal adaptive system will allow individual and group learners to interact with each other and discuss their own learning experience and understanding of course material, and resolve issues related to their class assignments. The adaptive system will be capable of representing key knowledge concepts in different ways and difficulty levels based on learners' differences, and lead to different understanding of the same STEM content by different learners. It will adapt specific pedagogical strategies to individual learners based on their characteristics, cognition, and preferences, allow authors to assemble remotely accessed learning material into courses, and provide facilities for instructors to assess (in real time) the perception of students of course material, monitor their progress in the learning process, and generate timely feedback based on their understanding or misconceptions. The system applies a set of ontologies that structure the learning process, with multiple user friendly Web interfaces. These include the learning ontology (models learning objects, educational resources, and learning goal); context ontology (supports adaptive strategy by detecting student situation), domain ontology (structures concepts and context), learner ontology (models student profile, preferences, and behavior), task ontologies, technological ontology (defines devices and places that surround the

  4. Adhesive Sociocultural Adaptation of Korean Immigrants in the U.S.: An Alternative Strategy of Minority Adaptation.

    ERIC Educational Resources Information Center

    Hurh, Won Moo; Kim, Kwang Chung

    1984-01-01

    "Adhesive adaptation" occurs when aspects of a new culture and social relations with members of the host society are added on to immigrants' traditional culture and social networks, without replacing or modifying any significant part of the old. Interviews with 615 Korean immigrants empirically confirmed this adaptation model. (Author/KH)

  5. Climate Change Predictions and Adaption Strategies for Coastal NASA Langley Research Center

    NASA Astrophysics Data System (ADS)

    De Young, R.

    2012-12-01

    Climate change could significantly impact the personal and operations of federal coastal laboratories. The Goddard Institute for Space Studies has made downscaled climate projections for Hampton Roads, Virginia a coastal region which includes NASA Langley Research Center (LaRC). These projections are being used to formulate adaptation and mitigation strategies to reduce climate change impacts at the center. Sea level rise and hurricanes will have significant impacts on LaRC and strategies such as surge modeling and tide gauge measurements and now underway. A proposed windbreak will reduce the impact of hurricane winds on center infrastructure. Disease vectors such as mosquitoes and ticks are being monitored and studied for their response to climate change. LaRC has significant forest and ecosystems which will be impacted by climate change and these impacts are being quantified. Mitigation strategies are being proposed such as the design of a 3 MW solar photovoltaic array to protect the center from brownouts and loss of power to critical missions. These and other programs will be discussed to reduce climate change impacts and allow LaRC to accomplish its mission into the next century.

  6. Comparative Proteogenomics of Twelve Roseobacter Exoproteomes Reveals Different Adaptive Strategies Among These Marine Bacteria*

    PubMed Central

    Christie-Oleza, Joseph Alexander; Piña-Villalonga, Juana Maria; Bosch, Rafael; Nogales, Balbina; Armengaud, Jean

    2012-01-01

    Roseobacters are generalist bacteria abundantly found in the oceans. Because little is known on how marine microorganisms interact in association or competition, we focused our attention on the microbial exoproteome, a key component in their interaction with extracellular milieu. Here we present a comparative analysis of the theoretically encoded exoproteome of twelve members of the Roseobacter group validated by extensive comparative proteogenomics. In silico analysis revealed that 30% of the encoded proteome of these microorganisms could be exported. The ratio of the different protein categories varied in accordance to the ecological distinctness of each strain, a trait reinforced by quantitative proteomics data. Despite the interspecies variations found, the most abundantly detected proteins by shotgun proteomics were from transporter, adhesion, motility, and toxin-like protein categories, defining four different plausible adaptive strategies within the Roseobacter group. In some strains the toxin-secretion strategy was over-represented with repeats-in-toxin-like proteins. Our results show that exoproteomes strongly depend on bacterial trophic strategy and can slightly change because of culture conditions. Simulated natural conditions and the effect of the indigenous microbial community on the exoproteome of Ruegeria pomeroyi DSS-3 were also assayed. Interestingly, we observed a significant depletion of the toxin-like proteins usually secreted by R. pomeroyi DSS-3 when grown in presence of a natural community sampled from a Mediterranean Sea port. The significance of this specific fraction of the exoproteome is discussed. PMID:22122883

  7. An Innovative Adaptive Pushover Procedure Based on Storey Shear

    SciTech Connect

    Shakeri, Kazem; Shayanfar, Mohsen A.

    2008-07-08

    Since the conventional pushover analyses are unable to consider the effect of the higher modes and progressive variation in dynamic properties, recent years have witnessed the development of some advanced adaptive pushover methods. However in these methods, using the quadratic combination rules to combine the modal forces result in a positive value in load pattern at all storeys and the reversal sign of the modes is removed; consequently these methods do not have a major advantage over their non-adaptive counterparts. Herein an innovative adaptive pushover method based on storey shear is proposed which can take into account the reversal signs in higher modes. In each storey the applied load pattern is derived from the storey shear profile; consequently, the sign of the applied loads in consecutive steps could be changed. Accuracy of the proposed procedure is examined by applying it to a 20-storey steel building. It illustrates a good estimation of the peak response in inelastic phase.

  8. Gain scheduling adaptive control strategies for HVDC systems to accommodate large disturbances

    SciTech Connect

    Reeve, J.; Sultan, M. )

    1994-02-01

    Techniques have been developed to permit the response of the controls for dc transmission systems to adapt to large system changes. A gain scheduling approach tunes the control as an on-line function of the effective short-circuit ratio and contingency indicators. The method has been tested by digital simulation, based on EMTP, of a back-to-back dc system. It has been found to be robust and control performance has been enhanced.

  9. Towards an integrated agenda for adaptation research: theory, practice, and policy: Strategy paper

    SciTech Connect

    Wilbanks, Thomas J; Patwardhan, Anand; Downing, Tom; Leary, Neil

    2009-01-01

    Adaptation to the adverse impacts of climate change has been recognized as a priority area for national and international policy. The findings of the Fourth Assessment Report of the IPCC have reemphasized the urgency of action and the scale of response needed to cope with climate change outcomes. The scientific community has an important role to play in advancing the information and knowledge base that would help in identifying, developing and implementing effective responses to enhance adaptive capacity and reduce vulnerability. This paper examines the way in which science and research could advance the adaptation agenda. To do so, we pose a number of questions aimed at identifying the knowledge gaps and research needs. We argue that in order to address these science and research needs, an integrated approach is necessary, one that combines new knowledge with new approaches for knowledge generation, and where research and practice co-evolve; and that such a learning-by-doing approach is essential to rapidly scale up and implement concrete adaptation actions.

  10. Modeling of the Urban Heat Island (UHI) using WRF - Assessment of adaptation and mitigation strategies for the city of Stuttgart.

    NASA Astrophysics Data System (ADS)

    Fallmann, Joachim; Suppan, Peter; Emeis, Stefan

    2013-04-01

    Cities are warmer than their surroundings (called urban heat island, UHI). UHI influence urban atmospheric circulation, air quality, and ecological conditions. UHI leads to upward motion and compensating near-surface inflow from the surroundings which import rural trace substances. Chemical and aerosol formation processes are modified due to increased temperature, reduced humidity and modified urban-rural trace substance mixtures. UHIs produce enhanced heat stress for humans, animals and plants, less water availability and modified air quality. Growing cities and Climate Change will aggravate the UHI and its effects and urgently require adaptation and mitigation strategies. Prior to this, UHI properties must be assessed by surface observations, ground- and satellite-based vertical remote sensing and numerical modelling. The Weather Research and Forecasting Model (WRF) is an instrument to simulate and assess this phenomenon based on boundary conditions from observations and global climate models. Three urbanization schemes are available with WRF, which are tested during this study for different weather conditions in central Europe and will be enhanced if necessary. High resolution land use maps are used for this modeling effort. In situ measurements and Landsat thermal images are employed for validation of the results. The study will focus on the city of Stuttgart located in the south western part of Germany that is situated in a caldera-like orographic feature. This municipality has a long tradition in urban climate research and thus is well equipped with climatologic measurement stations. By using Geographical Information Systems (GIS), it is possible to simulate several scenarios for different surface properties. By increasing the albedo of roof and wall layers in the urban canopy model or by replacing urban land use by natural vegetation, simple urban planning strategies can be tested and the effect on urban heat island formation and air quality can be

  11. Adaptive optics in digital micromirror based confocal microscopy

    NASA Astrophysics Data System (ADS)

    Pozzi, P.; Wilding, D.; Soloviev, O.; Vdovin, G.; Verhaegen, M.

    2016-03-01

    This proceeding reports early results in the development of a new technique for adaptive optics in confocal microscopy. The term adaptive optics refers to the branch of optics in which an active element in the optical system is used to correct inhomogeneities in the media through which light propagates. In its most classical form, mostly used in astronomical imaging, adaptive optics is achieved through a closed loop in which the actuators of a deformable mirror are driven by a wavefront sensor. This approach is severely limited in fluorescence microscopy, as the use of a wavefront sensor requires the presence of a bright, point like source in the field of view, a condition rarely satisfied in microscopy samples. Previously reported approaches to adaptive optics in fluorescence microscopy are therefore limited to the inclusion of fluorescent microspheres in the sample, to use as bright stars for wavefront sensors, or time consuming sensorless optimization procedures, requiring several seconds of optimization before the acquisition of a single image. We propose an alternative approach to the problem, implementing sensorless adaptive optics in a Programmable array microscope. A programmable array microscope is a microscope based on a digital micromirror device, in which the single elements of the micromirror act both as point sources and pinholes.

  12. Adaptation of Decoy Fusion Strategy for Existing Multi-Stage Search Workflows.

    PubMed

    Ivanov, Mark V; Levitsky, Lev I; Gorshkov, Mikhail V

    2016-09-01

    A number of proteomic database search engines implement multi-stage strategies aiming at increasing the sensitivity of proteome analysis. These approaches often employ a subset of the original database for the secondary stage of analysis. However, if target-decoy approach (TDA) is used for false discovery rate (FDR) estimation, the multi-stage strategies may violate the underlying assumption of TDA that false matches are distributed uniformly across the target and decoy databases. This violation occurs if the numbers of target and decoy proteins selected for the second search are not equal. Here, we propose a method of decoy database generation based on the previously reported decoy fusion strategy. This method allows unbiased TDA-based FDR estimation in multi-stage searches and can be easily integrated into existing workflows utilizing popular search engines and post-search algorithms. Graphical Abstract ᅟ. PMID:27349255

  13. Adaptation of Decoy Fusion Strategy for Existing Multi-Stage Search Workflows

    NASA Astrophysics Data System (ADS)

    Ivanov, Mark V.; Levitsky, Lev I.; Gorshkov, Mikhail V.

    2016-09-01

    A number of proteomic database search engines implement multi-stage strategies aiming at increasing the sensitivity of proteome analysis. These approaches often employ a subset of the original database for the secondary stage of analysis. However, if target-decoy approach (TDA) is used for false discovery rate (FDR) estimation, the multi-stage strategies may violate the underlying assumption of TDA that false matches are distributed uniformly across the target and decoy databases. This violation occurs if the numbers of target and decoy proteins selected for the second search are not equal. Here, we propose a method of decoy database generation based on the previously reported decoy fusion strategy. This method allows unbiased TDA-based FDR estimation in multi-stage searches and can be easily integrated into existing workflows utilizing popular search engines and post-search algorithms.

  14. Adaptation of Decoy Fusion Strategy for Existing Multi-Stage Search Workflows.

    PubMed

    Ivanov, Mark V; Levitsky, Lev I; Gorshkov, Mikhail V

    2016-09-01

    A number of proteomic database search engines implement multi-stage strategies aiming at increasing the sensitivity of proteome analysis. These approaches often employ a subset of the original database for the secondary stage of analysis. However, if target-decoy approach (TDA) is used for false discovery rate (FDR) estimation, the multi-stage strategies may violate the underlying assumption of TDA that false matches are distributed uniformly across the target and decoy databases. This violation occurs if the numbers of target and decoy proteins selected for the second search are not equal. Here, we propose a method of decoy database generation based on the previously reported decoy fusion strategy. This method allows unbiased TDA-based FDR estimation in multi-stage searches and can be easily integrated into existing workflows utilizing popular search engines and post-search algorithms. Graphical Abstract ᅟ.

  15. Forest adjacent households' voices on their perceptions and adaptation strategies to climate change in Kilombero District, Tanzania.

    PubMed

    Balama, Chelestino; Augustino, Suzana; Eriksen, Siri; Makonda, Fortunatus B S

    2016-01-01

    Climate change is a global and local challenge to both sustainable livelihoods and economic development. Tanzania as other countries of the world has been affected. Several studies have been conducted on farmers' perceptions and adaptation to climate change in the country, but little attention has been devoted to forest adjacent households in humid areas. This study assessed this gap through assessing forest adjacent households' voices on perceptions and adaptation strategies to climate change in Kilombero District, Tanzania. Data collection involved key informant interviews, focus group discussions and household questionnaires. Results showed that the majority of households perceived changed climate in terms of temperature increase, unpredictable rainfall, frequent occurrence of floods, increased dry spells during rainy season coupled with decreased water sources and emergence of new pests and diseases. The perceived change in climate has impacted agriculture productivity as the main livelihood source. Different coping and adaptation strategies are employed. These are; crop diversification, changing cropping calendar, adopting modern farming technologies, and increasing reliance on non-timber forest products. These strategies were positively and significantly influenced by socio-economic factors including household size, residence period, land ownership and household income. The study concludes that, there are changes in climatic conditions; and to respond to these climatic changes, forest adjacent households have developed numerous coping and adaptation strategies, which were positively and significantly influenced by some socio-economic factors. The study calls for actual implementation of local climate change policies and strategies in order to enhance adaptive capacity at household level. PMID:27390633

  16. Forest adjacent households' voices on their perceptions and adaptation strategies to climate change in Kilombero District, Tanzania.

    PubMed

    Balama, Chelestino; Augustino, Suzana; Eriksen, Siri; Makonda, Fortunatus B S

    2016-01-01

    Climate change is a global and local challenge to both sustainable livelihoods and economic development. Tanzania as other countries of the world has been affected. Several studies have been conducted on farmers' perceptions and adaptation to climate change in the country, but little attention has been devoted to forest adjacent households in humid areas. This study assessed this gap through assessing forest adjacent households' voices on perceptions and adaptation strategies to climate change in Kilombero District, Tanzania. Data collection involved key informant interviews, focus group discussions and household questionnaires. Results showed that the majority of households perceived changed climate in terms of temperature increase, unpredictable rainfall, frequent occurrence of floods, increased dry spells during rainy season coupled with decreased water sources and emergence of new pests and diseases. The perceived change in climate has impacted agriculture productivity as the main livelihood source. Different coping and adaptation strategies are employed. These are; crop diversification, changing cropping calendar, adopting modern farming technologies, and increasing reliance on non-timber forest products. These strategies were positively and significantly influenced by socio-economic factors including household size, residence period, land ownership and household income. The study concludes that, there are changes in climatic conditions; and to respond to these climatic changes, forest adjacent households have developed numerous coping and adaptation strategies, which were positively and significantly influenced by some socio-economic factors. The study calls for actual implementation of local climate change policies and strategies in order to enhance adaptive capacity at household level.

  17. Adaptive control with an expert system based supervisory level. Thesis

    NASA Technical Reports Server (NTRS)

    Sullivan, Gerald A.

    1991-01-01

    Adaptive control is presently one of the methods available which may be used to control plants with poorly modelled dynamics or time varying dynamics. Although many variations of adaptive controllers exist, a common characteristic of all adaptive control schemes, is that input/output measurements from the plant are used to adjust a control law in an on-line fashion. Ideally the adjustment mechanism of the adaptive controller is able to learn enough about the dynamics of the plant from input/output measurements to effectively control the plant. In practice, problems such as measurement noise, controller saturation, and incorrect model order, to name a few, may prevent proper adjustment of the controller and poor performance or instability result. In this work we set out to avoid the inadequacies of procedurally implemented safety nets, by introducing a two level control scheme in which an expert system based 'supervisor' at the upper level provides all the safety net functions for an adaptive controller at the lower level. The expert system is based on a shell called IPEX, (Interactive Process EXpert), that we developed specifically for the diagnosis and treatment of dynamic systems. Some of the more important functions that the IPEX system provides are: (1) temporal reasoning; (2) planning of diagnostic activities; and (3) interactive diagnosis. Also, because knowledge and control logic are separate, the incorporation of new diagnostic and treatment knowledge is relatively simple. We note that the flexibility available in the system to express diagnostic and treatment knowledge, allows much greater functionality than could ever be reasonably expected from procedural implementations of safety nets. The remainder of this chapter is divided into three sections. In section 1.1 we give a detailed review of the literature in the area of supervisory systems for adaptive controllers. In particular, we describe the evolution of safety nets from simple ad hoc techniques, up

  18. Adaptive gain control for spike-based map communication in a neuromorphic vision system.

    PubMed

    Meng, Yicong; Shi, Bertram E

    2008-06-01

    To support large numbers of model neurons, neuromorphic vision systems are increasingly adopting a distributed architecture, where different arrays of neurons are located on different chips or processors. Spike-based protocols are used to communicate activity between processors. The spike activity in the arrays depends on the input statistics as well as internal parameters such as time constants and gains. In this paper, we investigate strategies for automatically adapting these parameters to maintain a constant firing rate in response to changes in the input statistics. We find that under the constraint of maintaining a fixed firing rate, a strategy based upon updating the gain alone performs as well as an optimal strategy where both the gain and the time constant are allowed to vary. We discuss how to choose the time constant and propose an adaptive gain control mechanism whose operation is robust to changes in the input statistics. Our experimental results on a mobile robotic platform validate the analysis and efficacy of the proposed strategy.

  19. CALM: Complex Adaptive System (CAS)-Based Decision Support for Enabling Organizational Change

    NASA Astrophysics Data System (ADS)

    Adler, Richard M.; Koehn, David J.

    Guiding organizations through transformational changes such as restructuring or adopting new technologies is a daunting task. Such changes generate workforce uncertainty, fear, and resistance, reducing morale, focus and performance. Conventional project management techniques fail to mitigate these disruptive effects, because social and individual changes are non-mechanistic, organic phenomena. CALM (for Change, Adaptation, Learning Model) is an innovative decision support system for enabling change based on CAS principles. CALM provides a low risk method for validating and refining change strategies that combines scenario planning techniques with "what-if" behavioral simulation. In essence, CALM "test drives" change strategies before rolling them out, allowing organizations to practice and learn from virtual rather than actual mistakes. This paper describes the CALM modeling methodology, including our metrics for measuring organizational readiness to respond to change and other major CALM scenario elements: prospective change strategies; alternate futures; and key situational dynamics. We then describe CALM's simulation engine for projecting scenario outcomes and its associated analytics. CALM's simulator unifies diverse behavioral simulation paradigms including: adaptive agents; system dynamics; Monte Carlo; event- and process-based techniques. CALM's embodiment of CAS dynamics helps organizations reduce risk and improve confidence and consistency in critical strategies for enabling transformations.

  20. Rice Production Vulnerability to Climate Change in Indonesia: An Overview on Community-based Adaptation

    NASA Astrophysics Data System (ADS)

    Komaladara, A. A. S. P.; Budiasa, I. W.; Ambarawati, I. G. A. A.

    2015-12-01

    Rice remains to be a major crop and staple food in Indonesia. The task to ensure that rice production meets the demand of a growing population continues to engage the attention of national planners and policy makers. However, the adverse effects of climate change on agriculture production have presented Indonesia with yet another significant challenge. The exposure of rice crops to climate-related hazards such as temperature stress, floods, and drought, may lead to lower yield and self-sufficiency rate. This study explores the vulnerability of rice production to the effects of climate change in Indonesia. Considering the vast geographical span of the country and varying exposure, sensitivity, and adaptive capacity to climate change at regional level, this study emphasize the importance of community-based adaptation. Results from a simulation based on production and climate data from 1984 to 2014 indicates that rice production is sensitive to variation in growing season temperature and precipitation. A projection of these climate factors in 2050 has a significant impact on the major rice crop. To manage the impact of climate change, this study turns to the potential roles of farmer organizations, such as Subak, in adaptation strategies. The Subak in Bali is recognized for its cultural and organizational framework that highlights the sharing of knowledge and local wisdom in rice production. This is demonstrated by its efficient community-based irrigation management system, leading to sustainable rice production. Keywords: rice production, climate change, community-based adaptation, Indonesia

  1. Adaptively deformed mesh based interface method for elliptic equations with discontinuous coefficients

    PubMed Central

    Xia, Kelin; Zhan, Meng; Wan, Decheng; Wei, Guo-Wei

    2011-01-01

    Mesh deformation methods are a versatile strategy for solving partial differential equations (PDEs) with a vast variety of practical applications. However, these methods break down for elliptic PDEs with discontinuous coefficients, namely, elliptic interface problems. For this class of problems, the additional interface jump conditions are required to maintain the well-posedness of the governing equation. Consequently, in order to achieve high accuracy and high order convergence, additional numerical algorithms are required to enforce the interface jump conditions in solving elliptic interface problems. The present work introduces an interface technique based adaptively deformed mesh strategy for resolving elliptic interface problems. We take the advantages of the high accuracy, flexibility and robustness of the matched interface and boundary (MIB) method to construct an adaptively deformed mesh based interface method for elliptic equations with discontinuous coefficients. The proposed method generates deformed meshes in the physical domain and solves the transformed governed equations in the computational domain, which maintains regular Cartesian meshes. The mesh deformation is realized by a mesh transformation PDE, which controls the mesh redistribution by a source term. The source term consists of a monitor function, which builds in mesh contraction rules. Both interface geometry based deformed meshes and solution gradient based deformed meshes are constructed to reduce the L∞ and L2 errors in solving elliptic interface problems. The proposed adaptively deformed mesh based interface method is extensively validated by many numerical experiments. Numerical results indicate that the adaptively deformed mesh based interface method outperforms the original MIB method for dealing with elliptic interface problems. PMID:22586356

  2. Adaptive strategies in nocturnally migrating insects and songbirds: contrasting responses to wind.

    PubMed

    Chapman, Jason W; Nilsson, Cecilia; Lim, Ka S; Bäckman, Johan; Reynolds, Don R; Alerstam, Thomas

    2016-01-01

    Animals that use flight as their mode of transportation must cope with the fact that their migration and orientation performance is strongly affected by the flow of the medium they are moving in, that is by the winds. Different strategies can be used to mitigate the negative effects and benefit from the positive effects of a moving flow. The strategies an animal can use will be constrained by the relationship between the speed of the flow and the speed of the animal's own propulsion in relation to the surrounding air. Here we analyse entomological and ornithological radar data from north-western Europe to investigate how two different nocturnal migrant taxa, the noctuid moth Autographa gamma and songbirds, deal with wind by analysing variation in resulting flight directions in relation to the wind-dependent angle between the animal's heading and track direction. Our results, from fixed locations along the migratory journey, reveal different global strategies used by moths and songbirds during their migratory journeys. As expected, nocturnally migrating moths experienced a greater degree of wind drift than nocturnally migrating songbirds, but both groups were more affected by wind in autumn than in spring. The songbirds' strategies involve elements of both drift and compensation, providing some benefits from wind in combination with destination and time control. In contrast, moths expose themselves to a significantly higher degree of drift in order to obtain strong wind assistance, surpassing the songbirds in mean ground speed, at the cost of a comparatively lower spatiotemporal migratory precision. Moths and songbirds show contrasting but adaptive responses to migrating through a moving flow, which are fine-tuned to the respective flight capabilities of each group in relation to the wind currents they travel within.

  3. Adaptive strategies in nocturnally migrating insects and songbirds: contrasting responses to wind.

    PubMed

    Chapman, Jason W; Nilsson, Cecilia; Lim, Ka S; Bäckman, Johan; Reynolds, Don R; Alerstam, Thomas

    2016-01-01

    Animals that use flight as their mode of transportation must cope with the fact that their migration and orientation performance is strongly affected by the flow of the medium they are moving in, that is by the winds. Different strategies can be used to mitigate the negative effects and benefit from the positive effects of a moving flow. The strategies an animal can use will be constrained by the relationship between the speed of the flow and the speed of the animal's own propulsion in relation to the surrounding air. Here we analyse entomological and ornithological radar data from north-western Europe to investigate how two different nocturnal migrant taxa, the noctuid moth Autographa gamma and songbirds, deal with wind by analysing variation in resulting flight directions in relation to the wind-dependent angle between the animal's heading and track direction. Our results, from fixed locations along the migratory journey, reveal different global strategies used by moths and songbirds during their migratory journeys. As expected, nocturnally migrating moths experienced a greater degree of wind drift than nocturnally migrating songbirds, but both groups were more affected by wind in autumn than in spring. The songbirds' strategies involve elements of both drift and compensation, providing some benefits from wind in combination with destination and time control. In contrast, moths expose themselves to a significantly higher degree of drift in order to obtain strong wind assistance, surpassing the songbirds in mean ground speed, at the cost of a comparatively lower spatiotemporal migratory precision. Moths and songbirds show contrasting but adaptive responses to migrating through a moving flow, which are fine-tuned to the respective flight capabilities of each group in relation to the wind currents they travel within. PMID:26147535

  4. Assessing indigenous knowledge systems and climate change adaptation strategies in agriculture: A case study of Chagaka Village, Chikhwawa, Southern Malawi

    NASA Astrophysics Data System (ADS)

    Nkomwa, Emmanuel Charles; Joshua, Miriam Kalanda; Ngongondo, Cosmo; Monjerezi, Maurice; Chipungu, Felistus

    In Malawi, production from subsistence rain fed agriculture is highly vulnerable to climate change and variability. In response to the adverse effects of climate change and variability, a National Adaptation Programme of Action is used as framework for implementing adaptation programmes. However, this framework puts limited significance on indigenous knowledge systems (IKS). In many parts of the world, IKS have shown potential in the development of locally relevant and therefore sustainable adaptation strategies. This study was aimed at assessing the role of IKS in adaptation to climate change and variability in the agricultural sector in a rural district of Chikhwawa, southern Malawi. The study used both qualitative data from focus group and key informant interviews and quantitative data from household interviews and secondary data to address the research objectives. The study established that the local communities are able to recognise the changes in their climate and local environment. Commonly mentioned indicators of changing climatic patterns included delayed and unpredictable onset of rainfall, declining rainfall trends, warming temperatures and increased frequency of prolonged dry spells. An analysis of empirical data corroborates the people's perception. In addition, the community is able to use their IKS to adapt their agricultural systems to partially offset the effects of climate change. Like vulnerability to climate change, IKS varies over a short spatial scale, providing locally relevant adaptation to impacts of climate change. This paper therefore advocates for the integration of IKS in programmes addressing adaptation to climate change and vulnerability. This will serve to ensure sustainable and relevant adaptation strategies.

  5. EEG-Based BCI System Using Adaptive Features Extraction and Classification Procedures

    PubMed Central

    Mangia, Anna Lisa; Cappello, Angelo

    2016-01-01

    Motor imagery is a common control strategy in EEG-based brain-computer interfaces (BCIs). However, voluntary control of sensorimotor (SMR) rhythms by imagining a movement can be skilful and unintuitive and usually requires a varying amount of user training. To boost the training process, a whole class of BCI systems have been proposed, providing feedback as early as possible while continuously adapting the underlying classifier model. The present work describes a cue-paced, EEG-based BCI system using motor imagery that falls within the category of the previously mentioned ones. Specifically, our adaptive strategy includes a simple scheme based on a common spatial pattern (CSP) method and support vector machine (SVM) classification. The system's efficacy was proved by online testing on 10 healthy participants. In addition, we suggest some features we implemented to improve a system's “flexibility” and “customizability,” namely, (i) a flexible training session, (ii) an unbalancing in the training conditions, and (iii) the use of adaptive thresholds when giving feedback.

  6. EEG-Based BCI System Using Adaptive Features Extraction and Classification Procedures

    PubMed Central

    Mangia, Anna Lisa; Cappello, Angelo

    2016-01-01

    Motor imagery is a common control strategy in EEG-based brain-computer interfaces (BCIs). However, voluntary control of sensorimotor (SMR) rhythms by imagining a movement can be skilful and unintuitive and usually requires a varying amount of user training. To boost the training process, a whole class of BCI systems have been proposed, providing feedback as early as possible while continuously adapting the underlying classifier model. The present work describes a cue-paced, EEG-based BCI system using motor imagery that falls within the category of the previously mentioned ones. Specifically, our adaptive strategy includes a simple scheme based on a common spatial pattern (CSP) method and support vector machine (SVM) classification. The system's efficacy was proved by online testing on 10 healthy participants. In addition, we suggest some features we implemented to improve a system's “flexibility” and “customizability,” namely, (i) a flexible training session, (ii) an unbalancing in the training conditions, and (iii) the use of adaptive thresholds when giving feedback. PMID:27635129

  7. EEG-Based BCI System Using Adaptive Features Extraction and Classification Procedures.

    PubMed

    Mondini, Valeria; Mangia, Anna Lisa; Cappello, Angelo

    2016-01-01

    Motor imagery is a common control strategy in EEG-based brain-computer interfaces (BCIs). However, voluntary control of sensorimotor (SMR) rhythms by imagining a movement can be skilful and unintuitive and usually requires a varying amount of user training. To boost the training process, a whole class of BCI systems have been proposed, providing feedback as early as possible while continuously adapting the underlying classifier model. The present work describes a cue-paced, EEG-based BCI system using motor imagery that falls within the category of the previously mentioned ones. Specifically, our adaptive strategy includes a simple scheme based on a common spatial pattern (CSP) method and support vector machine (SVM) classification. The system's efficacy was proved by online testing on 10 healthy participants. In addition, we suggest some features we implemented to improve a system's "flexibility" and "customizability," namely, (i) a flexible training session, (ii) an unbalancing in the training conditions, and (iii) the use of adaptive thresholds when giving feedback.

  8. EEG-Based BCI System Using Adaptive Features Extraction and Classification Procedures.

    PubMed

    Mondini, Valeria; Mangia, Anna Lisa; Cappello, Angelo

    2016-01-01

    Motor imagery is a common control strategy in EEG-based brain-computer interfaces (BCIs). However, voluntary control of sensorimotor (SMR) rhythms by imagining a movement can be skilful and unintuitive and usually requires a varying amount of user training. To boost the training process, a whole class of BCI systems have been proposed, providing feedback as early as possible while continuously adapting the underlying classifier model. The present work describes a cue-paced, EEG-based BCI system using motor imagery that falls within the category of the previously mentioned ones. Specifically, our adaptive strategy includes a simple scheme based on a common spatial pattern (CSP) method and support vector machine (SVM) classification. The system's efficacy was proved by online testing on 10 healthy participants. In addition, we suggest some features we implemented to improve a system's "flexibility" and "customizability," namely, (i) a flexible training session, (ii) an unbalancing in the training conditions, and (iii) the use of adaptive thresholds when giving feedback. PMID:27635129

  9. Climate Change and Agriculture in Africa: Impact Assessment and Adaptation Strategies

    NASA Astrophysics Data System (ADS)

    Brown, Molly E.; McCusker, Brent

    2008-11-01

    As climate change has emerged as a significant threat, there is much concern about how vulnerable agricultural communities will adapt, particularly as global population continues to rise. Much of the current lack of productivity and economic marginalization of African agriculture arises from global trade regimes that give a competitive advantage to Western farmers, from low use of agricultural inputs, and from a dearth of infrastructure and services for the agriculture sector. For centuries, African farmers have used a wide variety of risk-reducing livelihood strategies, including diversifying income sources, switching crops, and investing in marketing. However, improving their productivity to ``modern'' levels has remained a distant dream, resulting in a continual reduction in investment in the sector over the past five decades.

  10. Private adaptation strategies and implementation in flood risk management: why people do nothing?

    NASA Astrophysics Data System (ADS)

    Karagiorgos, Konstantinos; Thaler, Thomas; Maris, Fotios; Paparrizos, Spyros; Fuchs, Sven

    2015-04-01

    In the past decades, vulnerability assessment has emerged as an important field of research in flood risk management, in particular with respect to climate change and necessary adaptation strategies for the society. Probably starting with Chamber's seminal article on vulnerability, coping and policy (Chambers 1989), and further developed as the causal structure of vulnerability by Bohle (2001) and others, at least two research paradigms exist: an internal side focusing on societal resilience and coping capacities, and an external side targeted at a reduction of negative effects in terms of loss reduction (Fuchs 2009). Despite considerable research effects, however, different definitions and concepts still dominate the debate; it is surely that different scientific disciplines are working with this term: natural scientists, engineers, social scientists or economists, to name just a few. Each discipline defines vulnerability in a way which fits to their disciplinary purposes (Fuchs et al. 2011). But why has there been so little progress in our ability to adapt to flood hazards? White et al. (2001) summarised this paradox in an article with the title "Knowing better and losing even more - the use of knowledge in hazard management". One of the fundamental reasons for the lack of progress is the continuing separation of research on natural processes and socio-economic processes without considering interaction between these systems (Fuchs & Keiler 2013), as well as between scientific research results and the policy implementation (Medd & Marvin 2005). Moreover, as many studies were focused on the vulnerability of least developed societies to natural hazards (O'Brien et al. 2008), there is a particular lack in studies targeted at an implementation of existing adaptation frameworks at the level of highly-developed countries (Field et al. 2012; Scolobig et al. 2012). This gap results in a challenge for attempts to develop formal models into practical application and policy

  11. 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

  12. Ca2+ cycling in heart cells from ground squirrels: adaptive strategies for intracellular Ca2+ homeostasis.

    PubMed

    Li, Xiao-Chen; Wei, Ling; Zhang, Guang-Qin; Bai, Zai-Ling; Hu, Ying-Ying; Zhou, Peng; Bai, Shu-Hua; Chai, Zhen; Lakatta, Edward G; Hao, Xue-Mei; Wang, Shi-Qiang

    2011-01-01

    Heart tissues from hibernating mammals, such as ground squirrels, are able to endure hypothermia, hypoxia and other extreme insulting factors that are fatal for human and nonhibernating mammals. This study was designed to understand adaptive mechanisms involved in intracellular Ca(2+) homeostasis in cardiomyocytes from the mammalian hibernator, ground squirrel, compared to rat. Electrophysiological and confocal imaging experiments showed that the voltage-dependence of L-type Ca(2+) current (I(Ca)) was shifted to higher potentials in ventricular myocytes from ground squirrels vs. rats. The elevated threshold of I(Ca) did not compromise the Ca(2+)-induced Ca(2+) release, because a higher depolarization rate and a longer duration of action potential compensated the voltage shift of I(Ca). Both the caffeine-sensitive and caffeine-resistant components of cytosolic Ca(2+) removal were more rapid in ground squirrels. Ca(2+) sparks in ground squirrels exhibited larger amplitude/size and much lower frequency than in rats. Due to the high I(Ca) threshold, low SR Ca(2+) leak and rapid cytosolic Ca(2+) clearance, heart cells from ground squirrels exhibited better capability in maintaining intracellular Ca(2+) homeostasis than those from rats and other nonhibernating mammals. These findings not only reveal adaptive mechanisms of hibernation, but also provide novel strategies against Ca(2+) overload-related heart diseases. PMID:21935466

  13. Multiple symbiont acquisition strategies as an adaptive mechanism in the coral Stylophora pistillata.

    PubMed

    Byler, Kristen A; Carmi-Veal, Maya; Fine, Maoz; Goulet, Tamar L

    2013-01-01

    In obligate symbioses, the host's survival relies on the successful acquisition and maintenance of symbionts. Symbionts can either be transferred from parent to offspring via direct inheritance (vertical transmission) or acquired anew each generation from the environment (horizontal transmission). With vertical symbiont transmission, progeny benefit by not having to search for their obligate symbionts, and, with symbiont inheritance, a mechanism exists for perpetuating advantageous symbionts. But, if the progeny encounter an environment that differs from that of their parent, they may be disadvantaged if the inherited symbionts prove suboptimal. Conversely, while in horizontal symbiont acquisition host survival hinges on an unpredictable symbiont source, an individual host may acquire genetically diverse symbionts well suited to any given environment. In horizontal acquisition, however, a potentially advantageous symbiont will not be transmitted to subsequent generations. Adaptation in obligate symbioses may require mechanisms for both novel symbiont acquisition and symbiont inheritance. Using denaturing-gradient gel electrophoresis and real-time PCR, we identified the dinoflagellate symbionts (genus Symbiodinium) hosted by the Red Sea coral Stylophora pistillata throughout its ontogenesis and over depth. We present evidence that S. pistillata juvenile colonies may utilize both vertical and horizontal symbiont acquisition strategies. By releasing progeny with maternally derived symbionts, that are also capable of subsequent horizontal symbiont acquisition, coral colonies may acquire physiologically advantageous novel symbionts that are then perpetuated via vertical transmission to subsequent generations. With symbiont inheritance, natural selection can act upon the symbiotic variability, providing a mechanism for coral adaptation.

  14. Effect of Roy’s Adaptation Model-Guided Education on Coping Strategies of the Veterans with Lower Extremities Amputation: A Double-Blind Randomized Controlled Clinical Trial

    PubMed Central

    Farsi, Zahra; Azarmi, Somayeh

    2016-01-01

    Background: Any defect in the extremities of the body can affect different life aspects. The purpose of this study was to investigate the effect of Roy’s adaptation model-guided education on coping strategies of the veterans with lower extremities amputation. Methods: In a double-blind randomized controlled clinical trial, 60 veterans with lower extremities amputation referring to Kowsar Orthotics and Prosthetics Center of Veterans Clinic in Tehran, Iran were recruited using convenience method and randomly assigned to intervention and control groups in 2013-2014. Lazarus and Folkman coping strategies questionnaire was used to collect the data. After completing the questionnaires in both groups, maladaptive behaviours were determined in the intervention group and an education program based on Roy’s adaptation model was implemented. After 2 months, both groups completed the questionnaires again. Data were analyzed using SPSS software. Results: Independent T-test showed that the score of the dimensions of coping strategies did not have a statistically significant difference between the intervention and control groups in the pre-intervention stage (P>0.05). This test showed a statistically significant difference between the two groups in the post-intervention stage in terms of the scores of different dimensions of coping strategies (P>0.05), except in dimensions of social support seeking and positive appraisal (P>0.05). Conclusion: The findings of this research indicated that the Roy’s adaptation model-guided education improved the majority of coping strategies in veterans with lower extremities amputation. It is recommended that further interventions based on Roy’s adaptation model should be performed to improve the coping of the veterans with lower extremities amputation. Trial Registration Number: IRCT2014081118763N1 PMID:27218110

  15. Neurocomputing strategies in decomposition based structural design

    NASA Technical Reports Server (NTRS)

    Szewczyk, Z.; Hajela, P.

    1993-01-01

    The present paper explores the applicability of neurocomputing strategies in decomposition based structural optimization problems. It is shown that the modeling capability of a backpropagation neural network can be used to detect weak couplings in a system, and to effectively decompose it into smaller, more tractable, subsystems. When such partitioning of a design space is possible, parallel optimization can be performed in each subsystem, with a penalty term added to its objective function to account for constraint violations in all other subsystems. Dependencies among subsystems are represented in terms of global design variables, and a neural network is used to map the relations between these variables and all subsystem constraints. A vector quantization technique, referred to as a z-Network, can effectively be used for this purpose. The approach is illustrated with applications to minimum weight sizing of truss structures with multiple design constraints.

  16. Comparison of Different Strategies for Selection/Adaptation of Mixed Microbial Cultures Able to Ferment Crude Glycerol Derived from Second-Generation Biodiesel.

    PubMed

    Varrone, C; Heggeset, T M B; Le, S B; Haugen, T; Markussen, S; Skiadas, I V; Gavala, H N

    2015-01-01

    Objective of this study was the selection and adaptation of mixed microbial cultures (MMCs), able to ferment crude glycerol generated from animal fat-based biodiesel and produce building-blocks and green chemicals. Various adaptation strategies have been investigated for the enrichment of suitable and stable MMC, trying to overcome inhibition problems and enhance substrate degradation efficiency, as well as generation of soluble fermentation products. Repeated transfers in small batches and fed-batch conditions have been applied, comparing the use of different inoculum, growth media, and Kinetic Control. The adaptation of activated sludge inoculum was performed successfully and continued unhindered for several months. The best results showed a substrate degradation efficiency of almost 100% (about 10 g/L glycerol in 21 h) and different dominant metabolic products were obtained, depending on the selection strategy (mainly 1,3-propanediol, ethanol, or butyrate). On the other hand, anaerobic sludge exhibited inactivation after a few transfers. To circumvent this problem, fed-batch mode was used as an alternative adaptation strategy, which led to effective substrate degradation and high 1,3-propanediol and butyrate production. Changes in microbial composition were monitored by means of Next Generation Sequencing, revealing a dominance of glycerol consuming species, such as Clostridium, Klebsiella, and Escherichia.

  17. Comparison of Different Strategies for Selection/Adaptation of Mixed Microbial Cultures Able to Ferment Crude Glycerol Derived from Second-Generation Biodiesel

    PubMed Central

    Varrone, C.; Heggeset, T. M. B.; Le, S. B.; Haugen, T.; Markussen, S.; Skiadas, I. V.; Gavala, H. N.

    2015-01-01

    Objective of this study was the selection and adaptation of mixed microbial cultures (MMCs), able to ferment crude glycerol generated from animal fat-based biodiesel and produce building-blocks and green chemicals. Various adaptation strategies have been investigated for the enrichment of suitable and stable MMC, trying to overcome inhibition problems and enhance substrate degradation efficiency, as well as generation of soluble fermentation products. Repeated transfers in small batches and fed-batch conditions have been applied, comparing the use of different inoculum, growth media, and Kinetic Control. The adaptation of activated sludge inoculum was performed successfully and continued unhindered for several months. The best results showed a substrate degradation efficiency of almost 100% (about 10 g/L glycerol in 21 h) and different dominant metabolic products were obtained, depending on the selection strategy (mainly 1,3-propanediol, ethanol, or butyrate). On the other hand, anaerobic sludge exhibited inactivation after a few transfers. To circumvent this problem, fed-batch mode was used as an alternative adaptation strategy, which led to effective substrate degradation and high 1,3-propanediol and butyrate production. Changes in microbial composition were monitored by means of Next Generation Sequencing, revealing a dominance of glycerol consuming species, such as Clostridium, Klebsiella, and Escherichia. PMID:26509171

  18. Conducting health survey research in a deep rural South African community: challenges and adaptive strategies

    PubMed Central

    2013-01-01

    Background In many parts of the developing world, rural health requires focused policy attention, informed by reliable, representative health data. Yet there is surprisingly little published material to guide health researchers who face the unique set of hurdles associated with conducting field research in remote rural areas. Methods In this paper we provide a detailed description of the key challenges encountered during health survey field research carried out in 2010 in a deep rural site in KwaZulu-Natal, South Africa. The aim of the field research was to collect data on the health of children aged 10 to 17 years old, and their primary adult caregivers, as part of a larger national health survey; the research was a collaboration between several South African and foreign universities, South African national government departments, and various NGO partners. In presenting each of the four fieldwork challenges encountered on this site, we describe the initial planning decisions made, the difficulties faced when implementing these in the field, and the adaptive strategies we used to respond to these challenges. We reflect on learnings of potential relevance for the research community. Results Our four key fieldwork challenges were scarce research capacity, staff relocation tensions, logistical constraints, and difficulties related to community buy-in. Addressing each of these obstacles required timely assessment of the situation and adaptation of field plans, in collaboration with our local NGO partner. Adaptive strategies included a greater use of local knowledge; the adoption of tribal authority boundaries as the smallest geopolitical units for sampling; a creative developmental approach to capacity building; and planned, on-going engagement with multiple community representatives. Conclusions We argue that in order to maintain high scientific standards of research and manage to ‘get the job done’ on the ground, it is necessary to respond to fieldwork challenges

  19. An adaptive strategy for reducing Feral Cat predation on endangered hawaiian birds

    USGS Publications Warehouse

    Hess, S.C.; Banko, P.C.; Hansen, H.

    2009-01-01

    Despite the long history of Feral Cats Felis catus in Hawai'i, there has been little research to provide strategies to improve control programmes and reduce depredation on endangered species. Our objective Was to develop a predictive model to determine how landscape features on Mauna Kea, such as habitat, elevation, and proximity to roads, may affect the number of Feral Cats captured at each trap. We used log-link generalized linear models and QAIC c model ranking criteria to determine the effect of these factors. We found that The number of cats captured per trap Was related to effort, habitat type, and Whether traps Were located on The West or North Slope of Mauna Kea. We recommend an adaptive management strategy to minimize trapping interference by non-target Small Indian Mongoose Herpestes auropunctatus with toxicants, to focus trapping efforts in M??mane Sophora chrysophylla habitat on the West slope of Mauna Kea, and to cluster traps near others that have previously captured multiple cats.

  20. [Strategies and mechanisms of soil springtails in adapting lower temperature environment: research progress].

    PubMed

    Liu, Jing; Wang, Yun-Biao; Wu, Dong-Hui

    2012-12-01

    Low temperature and drought are the main environmental factors threatening the animals living in arctic area and cold temperate regions. To adapt the severe environment, the animals should adopt appropriate strategies. As a group of arthopods with freeze-avoiding strategy, soil springtails have the similar ecological mechanisms and modes of cold resistance/tolerance as insects, manifesting in the cold acclimation and drought tolerance to decrease the damage of ice crystal formation. During cold acclimation, there are a rapid increase of glycerol, a rapid decrease of fucose and glucose, and the production of anti-freeze proteins (AFP) , and exists the inter-transformation of different kinds of lipids to improve the flow of cell membrane to protect the cell from low temperature injury. In addition, soil springtails have their own specific modes and mechanisms to tolerate low temperature stress, mainly the vertical migration under the protection of snow cover and the excretion of ice nucleator from haemolymph, illustrating that it's of significance to research the cryobiology of soil springtails. This paper summarized the modes and mechanisms of soil springtails in tolerating low temperature environment, reviewed the research progress on the eco-physiology of the springtails, discussed the existing problems of the researches on the low temperature tolerance of the springtails, and prospected the research directions of the springtails low temperature ecology under the background of global change. PMID:23479899

  1. Study on adaptive BTT reentry speed depletion guidance law based on BP neural network

    NASA Astrophysics Data System (ADS)

    Zheng, Zongzhun; Wang, Yongji; Wu, Hao

    2007-11-01

    Reentry guidance is one of the key technologies in hypersonic vehicle research field. In addition to the constraints on its final position coordinates, the vehicle must also impact the target from a specified direction with high precision. And therefore the adaptability of guidance law is critical to control the velocity of hypersonic vehicle and firing accuracy properly in different surroundings of large airspace. In this paper, a new adaptive guidance strategy based on Back Propagation (BP) neural network for the reentry mission of a generic hypersonic vehicle is presented. Depending on the nicer self-learn ability of BP neural network, the guidance law considers the influence of biggish mis-modeling of aerodynamics, structure error and other initial disturbances on the flight capability of vehicle. Consequently, terminal position accuracy and velocity are guaranteed, while many constraints are satisfied. Numerical simulation results clearly bring out the fact that the proposed reentry guidance law based on BP neural network is rational and effective.

  2. The genome of the Antarctic polyextremophile Nesterenkonia sp. AN1 reveals adaptive strategies for survival under multiple stress conditions.

    PubMed

    Aliyu, Habibu; De Maayer, Pieter; Cowan, Don

    2016-04-01

    Nesterenkonia sp. AN1 is a polyextremophile isolated from Antarctic desert soil. Genomic analyses and genome comparisons with three mesophilic Nesterenkonia strains indicated that the unique genome fraction of Nesterenkonia sp. AN1 contains adaptive features implicated in the response to cold stress including modulation of membrane fluidity as well as response to cold-associated osmotic and oxidative stress. The core genome also encodes a number of putative cold stress response proteins. RNA-Seq-based transcriptome analyses of Nesterenkonia sp. AN1 grown at 5ºC and 21°C showed that there was significant induction of transcripts that code for antioxidants at 5ºC, demonstrated by the upregulation of sodA, bcp and bpoA2. There was also overexpression of universal stress protein genes related to uspA, along with genes encoding other characterized cold stress features. Genes encoding the two key enzymes of the glyoxylate cycle, isocitrate lyase (ICL) and malate synthase (AceB) were induced at 5ºC, suggesting possible adaptation strategies for energy metabolism in cold habitats. These genomic features may contribute to the survival of Nesterenkonia sp. AN1 in arid Antarctic soils.

  3. Contrast-based sensorless adaptive optics for retinal imaging.

    PubMed

    Zhou, Xiaolin; Bedggood, Phillip; Bui, Bang; Nguyen, Christine T O; He, Zheng; Metha, Andrew

    2015-09-01

    Conventional adaptive optics ophthalmoscopes use wavefront sensing methods to characterize ocular aberrations for real-time correction. However, there are important situations in which the wavefront sensing step is susceptible to difficulties that affect the accuracy of the correction. To circumvent these, wavefront sensorless adaptive optics (or non-wavefront sensing AO; NS-AO) imaging has recently been developed and has been applied to point-scanning based retinal imaging modalities. In this study we show, for the first time, contrast-based NS-AO ophthalmoscopy for full-frame in vivo imaging of human and animal eyes. We suggest a robust image quality metric that could be used for any imaging modality, and test its performance against other metrics using (physical) model eyes.

  4. Adaptive reconnection-based arbitrary Lagrangian Eulerian method

    SciTech Connect

    Bo, Wurigen; Shashkov, Mikhail

    2015-07-21

    We present a new adaptive Arbitrary Lagrangian Eulerian (ALE) method. This method is based on the reconnection-based ALE (ReALE) methodology of Refs. [35], [34] and [6]. The main elements in a standard ReALE method are: an explicit Lagrangian phase on an arbitrary polygonal (in 2D) mesh in which the solution and positions of grid nodes are updated; a rezoning phase in which a new grid is defined by changing the connectivity (using Voronoi tessellation) but not the number of cells; and a remapping phase in which the Lagrangian solution is transferred onto the new grid. Furthermore, in the standard ReALE method, the rezoned mesh is smoothed by using one or several steps toward centroidal Voronoi tessellation, but it is not adapted to the solution in any way.

  5. Adaptive reconnection-based arbitrary Lagrangian Eulerian method

    DOE PAGES

    Bo, Wurigen; Shashkov, Mikhail

    2015-07-21

    We present a new adaptive Arbitrary Lagrangian Eulerian (ALE) method. This method is based on the reconnection-based ALE (ReALE) methodology of Refs. [35], [34] and [6]. The main elements in a standard ReALE method are: an explicit Lagrangian phase on an arbitrary polygonal (in 2D) mesh in which the solution and positions of grid nodes are updated; a rezoning phase in which a new grid is defined by changing the connectivity (using Voronoi tessellation) but not the number of cells; and a remapping phase in which the Lagrangian solution is transferred onto the new grid. Furthermore, in the standard ReALEmore » method, the rezoned mesh is smoothed by using one or several steps toward centroidal Voronoi tessellation, but it is not adapted to the solution in any way.« less

  6. Contrast-based sensorless adaptive optics for retinal imaging

    PubMed Central

    Zhou, Xiaolin; Bedggood, Phillip; Bui, Bang; Nguyen, Christine T.O.; He, Zheng; Metha, Andrew

    2015-01-01

    Conventional adaptive optics ophthalmoscopes use wavefront sensing methods to characterize ocular aberrations for real-time correction. However, there are important situations in which the wavefront sensing step is susceptible to difficulties that affect the accuracy of the correction. To circumvent these, wavefront sensorless adaptive optics (or non-wavefront sensing AO; NS-AO) imaging has recently been developed and has been applied to point-scanning based retinal imaging modalities. In this study we show, for the first time, contrast-based NS-AO ophthalmoscopy for full-frame in vivo imaging of human and animal eyes. We suggest a robust image quality metric that could be used for any imaging modality, and test its performance against other metrics using (physical) model eyes. PMID:26417525

  7. Hybrid and adaptive meta-model-based global optimization

    NASA Astrophysics Data System (ADS)

    Gu, J.; Li, G. Y.; Dong, Z.

    2012-01-01

    As an efficient and robust technique for global optimization, meta-model-based search methods have been increasingly used in solving complex and computation intensive design optimization problems. In this work, a hybrid and adaptive meta-model-based global optimization method that can automatically select appropriate meta-modelling techniques during the search process to improve search efficiency is introduced. The search initially applies three representative meta-models concurrently. Progress towards a better performing model is then introduced by selecting sample data points adaptively according to the calculated values of the three meta-models to improve modelling accuracy and search efficiency. To demonstrate the superior performance of the new algorithm over existing search methods, the new method is tested using various benchmark global optimization problems and applied to a real industrial design optimization example involving vehicle crash simulation. The method is particularly suitable for design problems involving computation intensive, black-box analyses and simulations.

  8. Adaptive directional wavelet transform based on directional prefiltering.

    PubMed

    Tanaka, Yuichi; Hasegawa, Madoka; Kato, Shigeo; Ikehara, Masaaki; Nguyen, Truong Q

    2010-04-01

    This paper proposes an efficient approach for adaptive directional wavelet transform (WT) based on directional prefiltering. Although the adaptive directional WT is able to transform an image along diagonal orientations as well as traditional horizontal and vertical directions, it sacrifices computation speed for good image coding performance. We present two efficient methods to find the best transform directions by prefiltering using 2-D filter bank or 1-D directional WT along two fixed directions. The proposed direction calculation methods achieve comparable image coding performance comparing to the conventional one with less complexity. Furthermore, transform direction data of the proposed method can be used for content-based image retrieval to increase retrieval ratio. PMID:20028625

  9. The effects of vehicular gap changes with memory on traffic flow in cooperative adaptive cruise control strategy

    NASA Astrophysics Data System (ADS)

    Yu, Shaowei; Shi, Zhongke

    2015-06-01

    To evaluate the impacts of new influence factor in cooperative adaptive cruise control strategy on the dynamic characteristics of traffic flow, an improved cooperative car-following model considering multiple vehicular gap changes with memory is developed to study the influences of multiple vehicular gap changes with memory on each car's speed, acceleration and relative distance. Some numerical simulations are carried out and the results show that considering multiple vehicular gap changes with memory in designing the cooperative adaptive cruise control strategy can improve the stability of traffic flow and reduce the accidental probability.

  10. Water supply sustainability and adaptation strategies under anthropogenic and climatic changes of a meso-scale Mediterranean catchment.

    PubMed

    Collet, Lila; Ruelland, Denis; Estupina, Valérie Borrell; Dezetter, Alain; Servat, Eric

    2015-12-01

    Assessing water supply sustainability is crucial to meet stakeholders' needs, notably in the Mediterranean. This region has been identified as a climate change hot spot, and as a region where water demand is continuously increasing due to population growth and the expansion of irrigated areas. The Hérault River catchment (2500 km2, France) is a typical example and a negative trend in discharge has been observed since the 1960s. In this context, local stakeholders need to evaluate possible future changes in water allocation capacity in the catchment, using climate change, dam management and water use scenarios. A modelling framework that was already calibrated and validated on this catchment over the last 50 years was used to assess whether water resources could meet water demands at the 2030 horizon for the domestic, agricultural and environmental sectors. Water supply sustainability was evaluated at the sub-basin scale according to priority allocations using a water supply capacity index, frequency of unsatisfactory years as well as the reliability, resilience and sustainability metrics. Water use projections were based on the evolution of population, per-unit water demand, irrigated areas, water supply network efficiency, as well as on the evaluation of a biological flow. Climate projections were based on an increase in temperature up to 2°C and a decrease in daily precipitation by 20%. Adaptation strategies considered reducing per-unit water demand for the domestic sector and the importation of water volume for the agricultural sector. The dissociated effects of water use and climatic constraints on water supply sustainability were evaluated. Results showed that the downstream portions would be the more impacted as they are the most exploited ones. In the domestic sector, sustainability indicators would be more degraded by climate change scenarios than water use constraints. In the agricultural sector the negative impact of water use scenarios would be

  11. Water supply sustainability and adaptation strategies under anthropogenic and climatic changes of a meso-scale Mediterranean catchment.

    PubMed

    Collet, Lila; Ruelland, Denis; Estupina, Valérie Borrell; Dezetter, Alain; Servat, Eric

    2015-12-01

    Assessing water supply sustainability is crucial to meet stakeholders' needs, notably in the Mediterranean. This region has been identified as a climate change hot spot, and as a region where water demand is continuously increasing due to population growth and the expansion of irrigated areas. The Hérault River catchment (2500 km2, France) is a typical example and a negative trend in discharge has been observed since the 1960s. In this context, local stakeholders need to evaluate possible future changes in water allocation capacity in the catchment, using climate change, dam management and water use scenarios. A modelling framework that was already calibrated and validated on this catchment over the last 50 years was used to assess whether water resources could meet water demands at the 2030 horizon for the domestic, agricultural and environmental sectors. Water supply sustainability was evaluated at the sub-basin scale according to priority allocations using a water supply capacity index, frequency of unsatisfactory years as well as the reliability, resilience and sustainability metrics. Water use projections were based on the evolution of population, per-unit water demand, irrigated areas, water supply network efficiency, as well as on the evaluation of a biological flow. Climate projections were based on an increase in temperature up to 2°C and a decrease in daily precipitation by 20%. Adaptation strategies considered reducing per-unit water demand for the domestic sector and the importation of water volume for the agricultural sector. The dissociated effects of water use and climatic constraints on water supply sustainability were evaluated. Results showed that the downstream portions would be the more impacted as they are the most exploited ones. In the domestic sector, sustainability indicators would be more degraded by climate change scenarios than water use constraints. In the agricultural sector the negative impact of water use scenarios would be

  12. An adaptive watershed management assessment based on watershed investigation data.

    PubMed

    Kang, Min Goo; Park, Seung Woo

    2015-05-01

    The aim of this study was to assess the states of watersheds in South Korea and to formulate new measures to improve identified inadequacies. The study focused on the watersheds of the Han River basin and adopted an adaptive watershed management framework. Using data collected during watershed investigation projects, we analyzed the management context of the study basin and identified weaknesses in water use management, flood management, and environmental and ecosystems management in the watersheds. In addition, we conducted an interview survey to obtain experts' opinions on the possible management of watersheds in the future. The results of the assessment show that effective management of the Han River basin requires adaptive watershed management, which includes stakeholders' participation and social learning. Urbanization was the key variable in watershed management of the study basin. The results provide strong guidance for future watershed management and suggest that nonstructural measures are preferred to improve the states of the watersheds and that consistent implementation of the measures can lead to successful watershed management. The results also reveal that governance is essential for adaptive watershed management in the study basin. A special ordinance is necessary to establish governance and aid social learning. Based on the findings, a management process is proposed to support new watershed management practices. The results will be of use to policy makers and practitioners who can implement the measures recommended here in the early stages of adaptive watershed management in the Han River basin. The measures can also be applied to other river basins.

  13. Visual-adaptation-mechanism based underwater object extraction

    NASA Astrophysics Data System (ADS)

    Chen, Zhe; Wang, Huibin; Xu, Lizhong; Shen, Jie

    2014-03-01

    Due to the major obstacles originating from the strong light absorption and scattering in a dynamic underwater environment, underwater optical information acquisition and processing suffer from effects such as limited range, non-uniform lighting, low contrast, and diminished colors, causing it to become the bottleneck for marine scientific research and projects. After studying and generalizing the underwater biological visual mechanism, we explore its advantages in light adaption which helps animals to precisely sense the underwater scene and recognize their prey or enemies. Then, aiming to transform the significant advantage of the visual adaptation mechanism into underwater computer vision tasks, a novel knowledge-based information weighting fusion model is established for underwater object extraction. With this bionic model, the dynamical adaptability is given to the underwater object extraction task, making them more robust to the variability of the optical properties in different environments. The capability of the proposed method to adapt to the underwater optical environments is shown, and its outperformance for the object extraction is demonstrated by comparison experiments.

  14. Adaptive Neural Network Based Control of Noncanonical Nonlinear Systems.

    PubMed

    Zhang, Yanjun; Tao, Gang; Chen, Mou

    2016-09-01

    This paper presents a new study on the adaptive neural network-based control of a class of noncanonical nonlinear systems with large parametric uncertainties. Unlike commonly studied canonical form nonlinear systems whose neural network approximation system models have explicit relative degree structures, which can directly be used to derive parameterized controllers for adaptation, noncanonical form nonlinear systems usually do not have explicit relative degrees, and thus their approximation system models are also in noncanonical forms. It is well-known that the adaptive control of noncanonical form nonlinear systems involves the parameterization of system dynamics. As demonstrated in this paper, it is also the case for noncanonical neural network approximation system models. Effective control of such systems is an open research problem, especially in the presence of uncertain parameters. This paper shows that it is necessary to reparameterize such neural network system models for adaptive control design, and that such reparameterization can be realized using a relative degree formulation, a concept yet to be studied for general neural network system models. This paper then derives the parameterized controllers that guarantee closed-loop stability and asymptotic output tracking for noncanonical form neural network system models. An illustrative example is presented with the simulation results to demonstrate the control design procedure, and to verify the effectiveness of such a new design method.

  15. Land use and management change under climate change adaptation and mitigation strategies: a U.S. case study

    USGS Publications Warehouse

    Mu, Jianhong E.; Wein, Anne; McCarl, Bruce

    2015-01-01

    We examine the effects of crop management adaptation and climate mitigation strategies on land use and land management, plus on related environmental and economic outcomes. We find that crop management adaptation (e.g. crop mix, new species) increases Greenhouse gas (GHG) emissions by 1.7 % under a more severe climate projection while a carbon price reduces total forest and agriculture GHG annual flux by 15 % and 9 %, respectively. This shows that trade-offs are likely between mitigation and adaptation. Climate change coupled with crop management adaptation has small and mostly negative effects on welfare; mitigation, which is implemented as a carbon price starting at $15 per metric ton carbon dioxide (CO2) equivalent with a 5 % annual increase rate, bolsters welfare carbon payments. When both crop management adaptation and carbon price are implemented the effects of the latter dominates.

  16. Culturally Adapting an Evidence-Based Parenting Intervention for Latino Immigrants: The Need to Integrate Fidelity and Cultural Relevance1

    PubMed Central

    Cardona, Jose Ruben Parra; Domenech-Rodriguez, Melanie; Forgatch, Marion; Sullivan, Cris; Bybee, Deborah; Holtrop, Kendal; Escobar-Chew, Ana Rocio; Tams, Lisa; Dates, Brian; Bernal, Guillermo

    2011-01-01

    Latinos constitute the largest ethnic minority group in the US. However, the cultural adaptation and dissemination of evidence-based parenting interventions among Latino populations continues to be scarce in spite of extensive research that demonstrates the long-term positive effects of these interventions. The purpose of this article is threefold: (a) justify the importance of cultural adaptation research as a key strategy to disseminate efficacious interventions among Latinos, (b) describe the initial steps of a program of prevention research with Latino immigrants aimed at culturally adapting an evidence-based intervention informed by parent management training (PMT) principles, and (c) discuss implications for advancing cultural adaptation prevention practice and research, based on the initial feasibility and cultural acceptability findings of the current investigation. PMID:22428711

  17. The development of adaptive decision making: Recognition-based inference in children and adolescents.

    PubMed

    Horn, Sebastian S; Ruggeri, Azzurra; Pachur, Thorsten

    2016-09-01

    Judgments about objects in the world are often based on probabilistic information (or cues). A frugal judgment strategy that utilizes memory (i.e., the ability to discriminate between known and unknown objects) as a cue for inference is the recognition heuristic (RH). The usefulness of the RH depends on the structure of the environment, particularly the predictive power (validity) of recognition. Little is known about developmental differences in use of the RH. In this study, the authors examined (a) to what extent children and adolescents recruit the RH when making judgments, and (b) around what age adaptive use of the RH emerges. Primary schoolchildren (M = 9 years), younger adolescents (M = 12 years), and older adolescents (M = 17 years) made comparative judgments in task environments with either high or low recognition validity. Reliance on the RH was measured with a hierarchical multinomial model. Results indicated that primary schoolchildren already made systematic use of the RH. However, only older adolescents adaptively adjusted their strategy use between environments and were better able to discriminate between situations in which the RH led to correct versus incorrect inferences. These findings suggest that the use of simple heuristics does not progress unidirectionally across development but strongly depends on the task environment, in line with the perspective of ecological rationality. Moreover, adaptive heuristic inference seems to require experience and a developed base of domain knowledge. (PsycINFO Database Record PMID:27505696

  18. More Water Resources but Less for Irrigation: Adaptation Strategy of the Yellow River in a Changing Environment

    NASA Astrophysics Data System (ADS)

    Tang, Q.; Yin, Y. Y.

    2015-12-01

    The Yellow River is the primary source of freshwater to the northern China. Increasing population and socio-economic development have put great pressure on water resources of the river basin. The anticipated climate and socio-economic changes may further increase water stress. Development of adaptation strategies would have significant implications for water and food security of this region. In this study, the outputs of multiple hydrological models forced with the bias-corrected climatic variables from multiple global climate models were used to assess the change in renewable water resources of the river basin in the 21st century. The outputs of multiple crop models were used to assess the change in agricultural water demand. The domestic and industrial water demands were estimated based on the future socio-economic conditions under the Shared Socio-economic Pathways (SSPs). Besides basic ecosystem needs for water which must be met, the water use in domestic and industrial sectors is considered to have a higher priority than the agricultural water use when water is insufficient. The results show that the renewable water resources of the basin would increase as global mean temperature increases while the water demand would grow much more rapidly, largely due to water demand increase in domestic and industrial sectors. In most of the sub-basins of the Yellow River basin, the available water resources can not sustain all the water use sectors starting from the next a few decades. As more water resources would be appropriated by domestic and industrial sectors, a part of irrigated area had to be converted to rainfed agriculture which led to a large reduction in food production. This study highlights the linked water and food security in a changing environment and suggests that the trade-off should be considered when developing regional adaptation strategies.

  19. Adaptive Strategies for Controls of Flexible Arms. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Yuan, Bau-San

    1989-01-01

    An adaptive controller for a modern manipulator has been designed based on asymptotical stability via the Lyapunov criterion with the output error between the system and a reference model used as the actuating control signal. Computer simulations were carried out to test the design. The combination of the adaptive controller and a system vibration and mode shape estimator show that the flexible arm should move along a pre-defined trajectory with high-speed motion and fast vibration setting time. An existing computer-controlled prototype two link manipulator, RALF (Robotic Arm, Large Flexible), with a parallel mechanism driven by hydraulic actuators was used to verify the mathematical analysis. The experimental results illustrate that assumed modes found from finite element techniques can be used to derive the equations of motion with acceptable accuracy. The robust adaptive (modal) control is implemented to compensate for unmodelled modes and nonlinearities and is compared with the joint feedback control in additional experiments. Preliminary results show promise for the experimental control algorithm.

  20. Adaptive optics actuation by means of van der Waals forces: a novel nanotechnology strategy to steer light by light

    NASA Astrophysics Data System (ADS)

    Pinto, Fabrizio

    2008-11-01

    The feasibility to carry out the contactless actuation and control of both continuous facesheet deformable mirrors and MOEMS segmented micromirrors by manipulating van der Waals forces between electrically neutral surfaces is discussed. As we show, appropriately engineering such surface forces allows for adaptive optics strategies that are fully scalable down to the nanostructure level and that are intimately based on the optical properties of the materials involved. Since the magnitude of unretarded van der Waals forces diverges as the third power of the distance between the adaptive surface and the back-facing, actuating boundary, the novel approach proposed herein remains effective as the device size decreases even enabling one to address individual atoms. In some implementations, the actuation mechanism is driven by the dependence of van der Waals forces in semiconductors on illumination. Therefore the possibility exists, with adequate power levels, to design feed-back loops driven exclusively by light. A remarkable property of dispersion forces is their drastic behavior as a function of the topology of the interacting surfaces. This fact, at the frontier of contemporary numerical investigations, leads to the consideration of geometries in which dispersion forces are expected to change from attractive to repulsive. Finally, van der Waals forces exist between all neutral materials and contactless actuation can be achieved, for instance, even if the reflecting surface is not a conductor. This will open new multidimensional parameter space to the use of suitably designed classes of adaptive optics materials, including dielectrics, semiconductors, and multilayered structures, such as photonic-band-gap crystals.

  1. Land-based approach to evaluate sustainable land management and adaptive capacity of ecosystems/lands

    NASA Astrophysics Data System (ADS)

    Kust, German; Andreeva, Olga

    2015-04-01

    A number of new concepts and paradigms appeared during last decades, such as sustainable land management (SLM), climate change (CC) adaptation, environmental services, ecosystem health, and others. All of these initiatives still not having the common scientific platform although some agreements in terminology were reached, schemes of links and feedback loops created, and some models developed. Nevertheless, in spite of all these scientific achievements, the land related issues are still not in the focus of CC adaptation and mitigation. The last did not grow much beyond the "greenhouse gases" (GHG) concept, which makes land degradation as the "forgotten side of climate change" The possible decision to integrate concepts of climate and desertification/land degradation could be consideration of the "GHG" approach providing global solution, and "land" approach providing local solution covering other "locally manifesting" issues of global importance (biodiversity conservation, food security, disasters and risks, etc.) to serve as a central concept among those. SLM concept is a land-based approach, which includes the concepts of both ecosystem-based approach (EbA) and community-based approach (CbA). SLM can serve as in integral CC adaptation strategy, being based on the statement "the more healthy and resilient the system is, the less vulnerable and more adaptive it will be to any external changes and forces, including climate" The biggest scientific issue is the methods to evaluate the SLM and results of the SLM investments. We suggest using the approach based on the understanding of the balance or equilibrium of the land and nature components as the major sign of the sustainable system. Prom this point of view it is easier to understand the state of the ecosystem stress, size of the "health", range of adaptive capacity, drivers of degradation and SLM nature, as well as the extended land use, and the concept of environmental land management as the improved SLM approach

  2. Prediction-based manufacturing center self-adaptive demand side energy optimization in cyber physical systems

    NASA Astrophysics Data System (ADS)

    Sun, Xinyao; Wang, Xue; Wu, Jiangwei; Liu, Youda

    2014-05-01

    Cyber physical systems(CPS) recently emerge as a new technology which can provide promising approaches to demand side management(DSM), an important capability in industrial power systems. Meanwhile, the manufacturing center is a typical industrial power subsystem with dozens of high energy consumption devices which have complex physical dynamics. DSM, integrated with CPS, is an effective methodology for solving energy optimization problems in manufacturing center. This paper presents a prediction-based manufacturing center self-adaptive energy optimization method for demand side management in cyber physical systems. To gain prior knowledge of DSM operating results, a sparse Bayesian learning based componential forecasting method is introduced to predict 24-hour electric load levels for specific industrial areas in China. From this data, a pricing strategy is designed based on short-term load forecasting results. To minimize total energy costs while guaranteeing manufacturing center service quality, an adaptive demand side energy optimization algorithm is presented. The proposed scheme is tested in a machining center energy optimization experiment. An AMI sensing system is then used to measure the demand side energy consumption of the manufacturing center. Based on the data collected from the sensing system, the load prediction-based energy optimization scheme is implemented. By employing both the PSO and the CPSO method, the problem of DSM in the manufacturing center is solved. The results of the experiment show the self-adaptive CPSO energy optimization method enhances optimization by 5% compared with the traditional PSO optimization method.

  3. Multiple environmental controls on phytoplankton growth strategies determine adaptive responses of the N : P ratio.

    PubMed

    Daines, Stuart J; Clark, James R; Lenton, Timothy M

    2014-04-01

    The controls on the 'Redfield' N : P stoichiometry of marine phytoplankton and hence the N : P ratio of the deep ocean remain incompletely understood. Here, we use a model for phytoplankton ecophysiology and growth, based on functional traits and resource-allocation trade-offs, to show how environmental filtering, biotic interactions, and element cycling in a global ecosystem model determine phytoplankton biogeography, growth strategies and macromolecular composition. Emergent growth strategies capture major observed patterns in marine biomes. Using a new synthesis of experimental RNA and protein measurements to constrain per-ribosome translation rates, we determine a spatially variable lower limit on adaptive rRNA:protein allocation and hence on the relationship between the largest cellular P and N pools. Comparison with the lowest observed phytoplankton N : P ratios and N : P export fluxes in the Southern Ocean suggests that additional contributions from phospholipid and phosphorus storage compounds play a fundamental role in determining the marine biogeochemical cycling of these elements.

  4. Analysis prediction of Indonesian banks (BCA, BNI, MANDIRI) using adaptive neuro-fuzzy inference system (ANFIS) and investment strategies

    NASA Astrophysics Data System (ADS)

    Trianto, Andriantama Budi; Hadi, I. M.; Liong, The Houw; Purqon, Acep

    2015-09-01

    Indonesian economical development is growing well. It has effect for their invesment in Banks and the stock market. In this study, we perform prediction for the three blue chips of Indonesian bank i.e. BCA, BNI, and MANDIRI by using the method of Adaptive Neuro-Fuzzy Inference System (ANFIS) with Takagi-Sugeno rules and Generalized bell (Gbell) as the membership function. Our results show that ANFIS perform good prediction with RMSE for BCA of 27, BNI of 5.29, and MANDIRI of 13.41, respectively. Furthermore, we develop an active strategy to gain more benefit. We compare between passive strategy versus active strategy. Our results shows that for the passive strategy gains 13 million rupiah, while for the active strategy gains 47 million rupiah in one year. The active investment strategy significantly shows gaining multiple benefit than the passive one.

  5. GestAqua.AdaPT - Mediterranean river basin modeling and reservoir operation strategies for climate change adaptation

    NASA Astrophysics Data System (ADS)

    Alexandre Diogo, Paulo; Nunes, João Pedro; Marco, Machado; Aal, Carlo; Carmona Rodrigues, António; Beça, Pedro; Casanova Lino, Rafael; Rocha, João; Carvalho Santos, Cláudia

    2016-04-01

    Climate change (CC) scenarios for the Mediterranean region include an increase in the frequency and intensity of extreme weather events such as drought periods. higher average temperatures and evapotranspiration, combined with the decrease of annual precipitation may strongly affect the sustainability of water resources. In face of these risks, improving water management actions? by anticipating necessary operational measures is required to insure water quantity and quality according to the needs of the populations and irrigation in agriculture. This is clearly the case of the Alentejo region, southern Portugal, where present climatic conditions already pose significant challenges to water resources stakeholders, mainly from the agricultural and the urban supply sectors. With this in mind, the GestAqua.AdaPT project is underway during 2015 and 2016, aiming at analyzing CC impacts until 2100 and develop operational procedures to ensure water needs are adequately satisfied in the Monte Novo and Vigia reservoirs, which supply water for the city of Évora and nearby irrigation systems. Specific project objectives include: a) defining management and operational adaptation strategies aiming to ensure resource sustainability, both quantitatively and qualitatively; b) evaluate future potential costs and available alternatives to the regional water transfer infrastructure linked with the large Alqueva reservoir implemented in 2011; c) defining CC adaptation strategies to reduce irrigation water needs and d) identification of CC adaptation strategies which can be suitable also to other similar water supply systems. The methodology is centered on the implementation of a cascade of modeling tools, allowing the integrated simulation of the multiple variables under analysis. The project is based on CC scenarios resulting from the CORDEX project for 10 combinations of Global and regional climate models (GCMs and RCMs). The study follows by using two of these combinations

  6. Adaptation strategies for health impacts of climate change in Western Australia: Application of a Health Impact Assessment framework

    SciTech Connect

    Spickett, Jeffery T.; Brown, Helen L.; Katscherian, Dianne

    2011-04-15

    Climate change is one of the greatest challenges facing the globe and there is substantial evidence that this will result in a number of health impacts, regardless of the level of greenhouse gas mitigation. It is therefore apparent that a combined approach of mitigation and adaptation will be required to protect public health. While the importance of mitigation is recognised, this project focused on the role of adaptation strategies in addressing the potential health impacts of climate change. The nature and magnitude of these health impacts will be determined by a number of parameters that are dependent upon the location. Firstly, climate change will vary between regions. Secondly, the characteristics of each region in terms of population and the ability to adapt to changes will greatly influence the extent of the health impacts that are experienced now and into the future. Effective adaptation measures therefore need to be developed with these differences in mind. A Health Impact Assessment (HIA) framework was used to consider the implications of climate change on the health of the population of Western Australia (WA) and to develop a range of adaptive responses suited to WA. A broad range of stakeholders participated in the HIA process, providing informed input into developing an understanding of the potential health impacts and potential adaptation strategies from a diverse sector perspective. Potential health impacts were identified in relation to climate change predictions in WA in the year 2030. The risk associated with each of these impacts was assessed using a qualitative process that considered the consequences and the likelihood of the health impact occurring. Adaptations were then developed which could be used to mitigate the identified health impacts and provide responses which could be used by Government for future decision making. The periodic application of a HIA framework is seen as an ideal tool to develop appropriate adaptation strategies to

  7. WE-G-BRF-09: Force- and Image-Adaptive Strategies for Robotised Placement of 4D Ultrasound Probes

    SciTech Connect

    Kuhlemann, I; Bruder, R; Ernst, F; Schweikard, A

    2014-06-15

    Purpose: To allow continuous acquisition of high quality 4D ultrasound images for non-invasive live tracking of tumours for IGRT, image- and force-adaptive strategies for robotised placement of 4D ultrasound probes are developed and evaluated. Methods: The developed robotised ultrasound system is based on a 6-axes industrial robot (adept Viper s850) carrying a 4D ultrasound transducer with a mounted force-torque sensor. The force-adaptive placement strategies include probe position control using artificial potential fields and contact pressure regulation by a PD controller strategy. The basis for live target tracking is a continuous minimum contact pressure to ensure good image quality and high patient comfort. This contact pressure can be significantly disturbed by respiratory movements and has to be compensated. All measurements were performed on human subjects under realistic conditions. When performing cardiac ultrasound, rib- and lung shadows are a common source of interference and can disrupt the tracking. To ensure continuous tracking, these artefacts had to be detected to automatically realign the probe. The detection is realised by multiple algorithms based on entropy calculations as well as a determination of the image quality. Results: Through active contact pressure regulation it was possible to reduce the variance of the contact pressure by 89.79% despite respiratory motion of the chest. The results regarding the image processing clearly demonstrate the feasibility to detect image artefacts like rib shadows in real-time. Conclusion: In all cases, it was possible to stabilise the image quality by active contact pressure control and automatically detected image artefacts. This fact enables the possibility to compensate for such interferences by realigning the probe and thus continuously optimising the ultrasound images. This is a huge step towards fully automated transducer positioning and opens the possibility for stable target tracking in

  8. Performance-based inspection and maintenance strategies

    SciTech Connect

    Vesely, W.E.

    1995-04-01

    Performance-based inspection and maintenance strategies utilize measures of equipment performance to help guide inspection and maintenance activities. A relevant measure of performance for safety system components is component unavailability. The component unavailability can also be input into a plant risk model such as a Probabilistic Risk Assessment (PRA) to determine the associated plant risk performance. Based on the present and projected unavailability performance, or the present and projected risk performance, the effectiveness of current maintenance activities can be evaluated and this information can be used to plan future maintenance activities. A significant amount of information other than downtimes or failure times is collected or can be collected when an inspection or maintenance is conducted which can be used to estimate the component unavailability. This information generally involves observations on the condition or state of the component or component piecepart. The information can be detailed such as the amount of corrosion buildup or can be general such as the general state of the component described as {open_quotes}high degradation{close_quotes}, {open_quotes}moderate degradation{close_quotes}, or {open_quotes}low degradation{close_quotes}. Much of the information collected in maintenance logs is qualitative and fuzzy. As part of an NRC Research program on performance-based engineering modeling, approaches have been developed to apply Fuzzy Set Theory to information collected on the state of the component to determine the implied component or component piecepart unavailability. Demonstrations of the applications of Fuzzy Set Theory are presented utilizing information from plant maintenance logs. The demonstrations show the power of Fuzzy Set Theory in translating engineering information to reliability and risk implications.

  9. Designing an Adaptive Web-Based Learning System Based on Students' Cognitive Styles Identified Online

    ERIC Educational Resources Information Center

    Lo, Jia-Jiunn; Chan, Ya-Chen; Yeh, Shiou-Wen

    2012-01-01

    This study developed an adaptive web-based learning system focusing on students' cognitive styles. The system is composed of a student model and an adaptation model. It collected students' browsing behaviors to update the student model for unobtrusively identifying student cognitive styles through a multi-layer feed-forward neural network (MLFF).…

  10. Episodic memories predict adaptive value-based decision-making.

    PubMed

    Murty, Vishnu P; FeldmanHall, Oriel; Hunter, Lindsay E; Phelps, Elizabeth A; Davachi, Lila

    2016-05-01

    Prior research illustrates that memory can guide value-based decision-making. For example, previous work has implicated both working memory and procedural memory (i.e., reinforcement learning) in guiding choice. However, other types of memories, such as episodic memory, may also influence decision-making. Here we test the role for episodic memory-specifically item versus associative memory-in supporting value-based choice. Participants completed a task where they first learned the value associated with trial unique lotteries. After a short delay, they completed a decision-making task where they could choose to reengage with previously encountered lotteries, or new never before seen lotteries. Finally, participants completed a surprise memory test for the lotteries and their associated values. Results indicate that participants chose to reengage more often with lotteries that resulted in high versus low rewards. Critically, participants not only formed detailed, associative memories for the reward values coupled with individual lotteries, but also exhibited adaptive decision-making only when they had intact associative memory. We further found that the relationship between adaptive choice and associative memory generalized to more complex, ecologically valid choice behavior, such as social decision-making. However, individuals more strongly encode experiences of social violations-such as being treated unfairly, suggesting a bias for how individuals form associative memories within social contexts. Together, these findings provide an important integration of episodic memory and decision-making literatures to better understand key mechanisms supporting adaptive behavior. PMID:26999046

  11. MEMS-based extreme adaptive optics for planet detection

    SciTech Connect

    Macintosh, B A; Graham, J R; Oppenheimer, B; Poyneer, L; Sivaramakrishnan, A; Veran, J

    2005-11-18

    The next major step in the study of extrasolar planets will be the direct detection, resolved from their parent star, of a significant sample of Jupiter-like extrasolar giant planets. Such detection will open up new parts of the extrasolar planet distribution and allow spectroscopic characterization of the planets themselves. Detecting Jovian planets at 5-50 AU scale orbiting nearby stars requires adaptive optics systems and coronagraphs an order of magnitude more powerful than those available today--the realm of ''Extreme'' adaptive optics. We present the basic requirements and design for such a system, the Gemini Planet Imager (GPI.) GPI will require a MEMS-based deformable mirror with good surface quality, 2-4 micron stroke (operated in tandem with a conventional low-order ''woofer'' mirror), and a fully-functional 48-actuator-diameter aperture.

  12. Adaptive Estimation of Intravascular Shear Rate Based on Parameter Optimization

    NASA Astrophysics Data System (ADS)

    Nitta, Naotaka; Takeda, Naoto

    2008-05-01

    The relationships between the intravascular wall shear stress, controlled by flow dynamics, and the progress of arteriosclerosis plaque have been clarified by various studies. Since the shear stress is determined by the viscosity coefficient and shear rate, both factors must be estimated accurately. In this paper, an adaptive method for improving the accuracy of quantitative shear rate estimation was investigated. First, the parameter dependence of the estimated shear rate was investigated in terms of the differential window width and the number of averaged velocity profiles based on simulation and experimental data, and then the shear rate calculation was optimized. The optimized result revealed that the proposed adaptive method of shear rate estimation was effective for improving the accuracy of shear rate calculation.

  13. Local Farmers' Perceptions of Climate Change and Local Adaptive Strategies: A Case Study from the Middle Yarlung Zangbo River Valley, Tibet, China

    NASA Astrophysics Data System (ADS)

    Li, Chunyan; Tang, Ya; Luo, Han; Di, Baofeng; Zhang, Liyun

    2013-10-01

    Climate change affects the productivity of agricultural ecosystems. Farmers cope with climate change based on their perceptions of changing climate patterns. Using a case study from the Middle Yarlung Zangbo River Valley, we present a new research framework that uses questionnaire and interview methods to compare local farmers' perceptions of climate change with the adaptive farming strategies they adopt. Most farmers in the valley believed that temperatures had increased in the last 30 years but did not note any changes in precipitation. Most farmers also reported sowing and harvesting hulless barley 10-15 days earlier than they were 20 years ago. In addition, farmers observed that plants were flowering and river ice was melting earlier in the season, but they did not perceive changes in plant germination, herbaceous vegetation growth, or other spring seasonal events. Most farmers noticed an extended fall season signified by delays in the freezing of rivers and an extended growing season for grassland vegetation. The study results showed that agricultural practices in the study area are still traditional; that is, local farmers' perceptions of climate change and their strategies to mitigate its impacts were based on indigenous knowledge and their own experiences. Adaptive strategies included adjusting planting and harvesting dates, changing crop species, and improving irrigation infrastructure. However, the farmers' decisions could not be fully attributed to their concerns about climate change. Local farming systems exhibit high adaptability to climate variability. Additionally, off-farm income has reduced the dependence of the farmers on agriculture, and an agricultural subsidy from the Chinese Central Government has mitigated the farmers' vulnerability. Nevertheless, it remains necessary for local farmers to build a system of adaptive climate change strategies that combines traditional experience and indigenous knowledge with scientific research and government

  14. Local farmers' perceptions of climate change and local adaptive strategies: a case study from the Middle Yarlung Zangbo River Valley, Tibet, China.

    PubMed

    Li, Chunyan; Tang, Ya; Luo, Han; Di, Baofeng; Zhang, Liyun

    2013-10-01

    Climate change affects the productivity of agricultural ecosystems. Farmers cope with climate change based on their perceptions of changing climate patterns. Using a case study from the Middle Yarlung Zangbo River Valley, we present a new research framework that uses questionnaire and interview methods to compare local farmers' perceptions of climate change with the adaptive farming strategies they adopt. Most farmers in the valley believed that temperatures had increased in the last 30 years but did not note any changes in precipitation. Most farmers also reported sowing and harvesting hulless barley 10-15 days earlier than they were 20 years ago. In addition, farmers observed that plants were flowering and river ice was melting earlier in the season, but they did not perceive changes in plant germination, herbaceous vegetation growth, or other spring seasonal events. Most farmers noticed an extended fall season signified by delays in the freezing of rivers and an extended growing season for grassland vegetation. The study results showed that agricultural practices in the study area are still traditional; that is, local farmers' perceptions of climate change and their strategies to mitigate its impacts were based on indigenous knowledge and their own experiences. Adaptive strategies included adjusting planting and harvesting dates, changing crop species, and improving irrigation infrastructure. However, the farmers' decisions could not be fully attributed to their concerns about climate change. Local farming systems exhibit high adaptability to climate variability. Additionally, off-farm income has reduced the dependence of the farmers on agriculture, and an agricultural subsidy from the Chinese Central Government has mitigated the farmers' vulnerability. Nevertheless, it remains necessary for local farmers to build a system of adaptive climate change strategies that combines traditional experience and indigenous knowledge with scientific research and

  15. Changes in Ecosystem Services and related Livelihoods in the Mekong Delta: vulnerabilities and adaptation strategies

    NASA Astrophysics Data System (ADS)

    Sebesvari, Z.; Renaud, F. G.

    2014-12-01

    The Mekong Delta (Vietnam) is highly vulnerable to the many impacts of global environmental change as well as to the accelerating anthropogenic changes in the catchment and in the delta itself. Today the delta is an agricultural landscape controlled by engineering structures such as channels, dykes, embankments, and sluice gates. These structures have been constructed gradually over the last 200 years mainly for irrigation and flood control in the upper part of the delta and to control saline intrusion in the coastal areas. Recent changes in the hydrology mainly driven by upstream hydropower development on the mainstream and the tributaries of the Mekong will likely have far reaching impacts on the delta´s social-ecological systems through changes in e.g. sedimentation processes, nutrient transport as well as the health of aquatic ecosystems. Further threats to the delta include sea level rise and an increase in seasonal rainfall variability leading to an increase in flood variability. These changes affect the lives of millions of low-income inhabitants who depend on the ecosystem services provided by the Mekong for their livelihoods and sustenance. Since the changes in ecosystem service provision are occurring relatively fast while the resource dependency of the delta population is very high, adaptation becomes a challenge. An assessment of livelihood dependencies on ecosystem services requires an understanding of ecosystem services affected by different drivers of change, as well as of the types of livelihoods likely to be jeopardized as a result of these changes. We will present main ecosystem services supporting specific livelihoods, discuss how they are threatened, and analyse the merits of potential solutions. Options based solely on grey infrastructure might be problematic on the long term while an integration of ecosystem based solution such as a (re)adaptation of agricultural production systems to floods in the upper delta might be a more sustainable

  16. Chemotactic signal transduction and phosphate metabolism as adaptive strategies during citrus canker induction by Xanthomonas citri.

    PubMed

    Moreira, Leandro Marcio; Facincani, Agda Paula; Ferreira, Cristiano Barbalho; Ferreira, Rafael Marine; Ferro, Maria Inês Tiraboshi; Gozzo, Fabio Cesar; de Oliveira, Julio Cezar Franco; Ferro, Jesus Aparecido; Soares, Márcia Regina

    2015-03-01

    The genome of Xanthomonas citri subsp. Citri strain 306 pathotype A (Xac) was completely sequenced more than 10 years; to date, few studies involving functional genomics Xac and its host compatible have been developed, specially related to adaptive events that allow the survival of Xac within the plant. Proteomic analysis of Xac showed that the processes of chemotactic signal transduction and phosphate metabolism are key adaptive strategies during the interaction of a pathogenic bacterium with its plant host. The results also indicate the importance of a group of proteins that may not be directly related to the classical virulence factors, but that are likely fundamental to the success of the initial stages of the infection, such as methyl-accepting chemotaxis protein (Mcp) and phosphate specific transport (Pst). Furthermore, the analysis of the mutant of the gene pstB which codifies to an ABC phosphate transporter subunit revealed a complete absence of citrus canker symptoms when inoculated in compatible hosts. We also conducted an in silico analysis which established the possible network of genes regulated by two-component systems PhoPQ and PhoBR (related to phosphate metabolism), and possible transcriptional factor binding site (TFBS) motifs of regulatory proteins PhoB and PhoP, detaching high degree of conservation of PhoB TFBS in 84 genes of Xac genome. This is the first time that chemotaxis signal transduction and phosphate metabolism were therefore indicated to be fundamental to the process of colonization of plant tissue during the induction of disease associated with Xanthomonas genus bacteria.

  17. Protein cold adaptation strategy via a unique seven-amino acid domain in the icefish (Chionodraco hamatus) PEPT1 transporter.

    PubMed

    Rizzello, Antonia; Romano, Alessandro; Kottra, Gabor; Acierno, Raffaele; Storelli, Carlo; Verri, Tiziano; Daniel, Hannelore; Maffia, Michele

    2013-04-23

    Adaptation of organisms to extreme environments requires proteins to work at thermodynamically unfavorable conditions. To adapt to subzero temperatures, proteins increase the flexibility of parts of, or even the whole, 3D structure to compensate for the lower thermal kinetic energy available at low temperatures. This may be achieved through single-site amino acid substitutions in regions of the protein that undergo large movements during the catalytic cycle, such as in enzymes or transporter proteins. Other strategies of cold adaptation involving changes in the primary amino acid sequence have not been documented yet. In Antarctic icefish (Chionodraco hamatus) peptide transporter 1 (PEPT1), the first transporter cloned from a vertebrate living at subzero temperatures, we came upon a unique principle of cold adaptation. A de novo domain composed of one to six repeats of seven amino acids (VDMSRKS), placed as an extra stretch in the cytosolic COOH-terminal region, contributed per se to cold adaptation. VDMSRKS was in a protein region uninvolved in transport activity and, notably, when transferred to the COOH terminus of a warm-adapted (rabbit) PEPT1, it conferred cold adaptation to the receiving protein. Overall, we provide a paradigm for protein cold adaptation that relies on insertion of a unique domain that confers greater affinity and maximal transport rates at low temperatures. Due to its ability to transfer a thermal trait, the VDMSRKS domain represents a useful tool for future cell biology or biotechnological applications. PMID:23569229

  18. Adaptive bad pixel correction algorithm for IRFPA based on PCNN

    NASA Astrophysics Data System (ADS)

    Leng, Hanbing; Zhou, Zuofeng; Cao, Jianzhong; Yi, Bo; Yan, Aqi; Zhang, Jian

    2013-10-01

    Bad pixels and response non-uniformity are the primary obstacles when IRFPA is used in different thermal imaging systems. The bad pixels of IRFPA include fixed bad pixels and random bad pixels. The former is caused by material or manufacture defect and their positions are always fixed, the latter is caused by temperature drift and their positions are always changing. Traditional radiometric calibration-based bad pixel detection and compensation algorithm is only valid to the fixed bad pixels. Scene-based bad pixel correction algorithm is the effective way to eliminate these two kinds of bad pixels. Currently, the most used scene-based bad pixel correction algorithm is based on adaptive median filter (AMF). In this algorithm, bad pixels are regarded as image noise and then be replaced by filtered value. However, missed correction and false correction often happens when AMF is used to handle complex infrared scenes. To solve this problem, a new adaptive bad pixel correction algorithm based on pulse coupled neural networks (PCNN) is proposed. Potential bad pixels are detected by PCNN in the first step, then image sequences are used periodically to confirm the real bad pixels and exclude the false one, finally bad pixels are replaced by the filtered result. With the real infrared images obtained from a camera, the experiment results show the effectiveness of the proposed algorithm.

  19. Experiments on Adaptive Techniques for Host-Based Intrusion Detection

    SciTech Connect

    DRAELOS, TIMOTHY J.; COLLINS, MICHAEL J.; DUGGAN, DAVID P.; THOMAS, EDWARD V.; WUNSCH, DONALD

    2001-09-01

    This research explores four experiments of adaptive host-based intrusion detection (ID) techniques in an attempt to develop systems that can detect novel exploits. The technique considered to have the most potential is adaptive critic designs (ACDs) because of their utilization of reinforcement learning, which allows learning exploits that are difficult to pinpoint in sensor data. Preliminary results of ID using an ACD, an Elman recurrent neural network, and a statistical anomaly detection technique demonstrate an ability to learn to distinguish between clean and exploit data. We used the Solaris Basic Security Module (BSM) as a data source and performed considerable preprocessing on the raw data. A detection approach called generalized signature-based ID is recommended as a middle ground between signature-based ID, which has an inability to detect novel exploits, and anomaly detection, which detects too many events including events that are not exploits. The primary results of the ID experiments demonstrate the use of custom data for generalized signature-based intrusion detection and the ability of neural network-based systems to learn in this application environment.

  20. The Formative Method for Adapting Psychotherapy (FMAP): A community-based developmental approach to culturally adapting therapy

    PubMed Central

    Hwang, Wei-Chin

    2010-01-01

    How do we culturally adapt psychotherapy for ethnic minorities? Although there has been growing interest in doing so, few therapy adaptation frameworks have been developed. The majority of these frameworks take a top-down theoretical approach to adapting psychotherapy. The purpose of this paper is to introduce a community-based developmental approach to modifying psychotherapy for ethnic minorities. The Formative Method for Adapting Psychotherapy (FMAP) is a bottom-up approach that involves collaborating with consumers to generate and support ideas for therapy adaptation. It involves 5-phases that target developing, testing, and reformulating therapy modifications. These phases include: (a) generating knowledge and collaborating with stakeholders (b) integrating generated information with theory and empirical and clinical knowledge, (c) reviewing the initial culturally adapted clinical intervention with stakeholders and revising the culturally adapted intervention, (d) testing the culturally adapted intervention, and (e) finalizing the culturally adapted intervention. Application of the FMAP is illustrated using examples from a study adapting psychotherapy for Chinese Americans, but can also be readily applied to modify therapy for other ethnic groups. PMID:20625458

  1. Impact of climate change and adaptation strategies on crop production in Nigeria

    NASA Astrophysics Data System (ADS)

    Mereu, V.; Gallo, A.; Carboni, G.; Spano, D.

    2012-04-01

    The vulnerability of agricultural to climate change is of particular interest to policy makers because the high social and economical importance of agriculture sector in Nigeria, which contributes approximately 40 percent to total GDP and support 70 percent of the population. It is necessary to investigate the potential climate change impacts in order to identify specific agricultural sectors and Agro-Ecological Zones that will be more vulnerable to changes in climatic conditions and implement and develop the most appropriate policies to cope with these changes. In this framework, this study aimed to assess the climate change impacts on Nigerian agricultural sector and to explore some of potential adaptation strategies for the most important crops in the food basket of the Country. The analysis was made using the DSSAT-CSM (Decision Support System for Agrotechnology Transfer - Cropping System Model) software, version 4.5. Crop simulation models included in DSSAT are tools that allows to simulate physiological process of crop growth, development and production, by combining genetic crop characteristics and environmental (soil and weather) conditions. In this analysis, for each selected crop, the models included into DSSAT-CSM software were ran, after a calibration phase, to evaluate climate change impacts on crop production. The climate data used for the analysis are derived by the Regional Circulation Model COSMO-CLM, from 1971 to 2065, at 8 km of spatial resolution. The RCM model output were "perturbed" with 10 Global Climate Models in order to have a wide variety of possible climate projections for impact analysis. Multiple combinations of soils and climate conditions, crop management and varieties were considered for each Agro-Ecological Zone of Nigeria. The climate impact assessment was made by comparing the yield obtained with the climate data for the present period and the yield obtainable under future changed climate conditions. The models ran by keeping

  2. Scribing: A Technology-Based Instructional Strategy

    ERIC Educational Resources Information Center

    Harless, Patrick

    2011-01-01

    In this article, the author presents one instructional strategy--scribing--tailored to the Tablet PC. He illustrates the role of the scribe during discussion through two classroom examples: (1) generalizing the polygon sum theorem; and (2) proving the third angle theorem. Then he analyzes scribing as an instructional strategy as well as students'…

  3. Understanding the Acculturation Experience of Chinese Adolescent Students: Sociocultural Adaptation Strategies and a Positive Bicultural and Bilingual Identity

    ERIC Educational Resources Information Center

    Tong, Virginia M.

    2014-01-01

    The acculturation of Chinese immigrant high school students was examined as it relates to students' level of interaction with teachers and peers and participation in American school activities. Findings from a regression analysis revealed five variables (sociocultural adaptation strategies) that facilitate students' adjustment process:…

  4. Expanding Acculturation Theory: Are Acculturation Models and the Adaptiveness of Acculturation Strategies Generalizable in a Colonial Context?

    ERIC Educational Resources Information Center

    Cheung-Blunden, Violet L.; Juang, Linda P.

    2008-01-01

    Most acculturation research has been conducted in immigrant settings. The present study examined the generalizability of acculturation models and the adaptiveness of acculturation strategies in another bicultural environment--a colonial setting. The sample included 138 girls (M = 13.8 years) and their parents from Hong Kong, a former British…

  5. Design of a Performance-Adaptive PID Control System Based on Modeling Performance Assessment

    NASA Astrophysics Data System (ADS)

    Yamamoto, Toru

    In industrial processes represented by petroleum and refinery processes, it is necessary to establish the performance-driven control strategy in order to improve the productivity, which the control performance is firstly evaluated, and the controller is reconstructed. This paper describes a design scheme of performance-adaptive PID controllers which are based on the above control mechanism. According to the proposed control scheme, the system identification works corresponding to the result of modeling performance assessment, and PID parameters are computed using the newly estimated system parameters. In calculating the PID parameters, the desired control performance is considered. The behaviour of the proposed control scheme is numerically examined in some simulation examples.

  6. Tensor dissimilarity based adaptive seeding algorithm for DT-MRI visualization with streamtubes

    NASA Astrophysics Data System (ADS)

    Weldeselassie, Yonas T.; Hamarneh, Ghassan; Weiskopf, Daniel

    2007-03-01

    In this paper, we propose an adaptive seeding strategy for visualization of diffusion tensor magnetic resonance imaging (DT-MRI) data using streamtubes. DT-MRI is a medical imaging modality that captures unique water diffusion properties and fiber orientation information of the imaged tissues. Visualizing DT-MRI data using streamtubes has the advantage that not only the anisotropic nature of the diffusion is visualized but also the underlying anatomy of biological structures is revealed. This makes streamtubes significant for the analysis of fibrous tissues in medical images. In order to avoid rendering multiple similar streamtubes, an adaptive seeding strategy is employed which takes into account similarity of tensors in a given region. The goal is to automate the process of generating seed points such that regions with dissimilar tensors are assigned more seed points compared to regions with similar tensors. The algorithm is based on tensor dissimilarity metrics that take into account both diffusion magnitudes and directions to optimize the seeding positions and density of streamtubes in order to reduce the visual clutter. Two recent advances in tensor calculus and tensor dissimilarity metrics are utilized: the Log-Euclidean and the J-divergence. Results show that adaptive seeding not only helps to cull unnecessary streamtubes that would obscure visualization but also do so without having to compute the culled streamtubes, which makes the visualization process faster.

  7. Using AQUACROP to model the impacts of future climates on crop production and possible adaptation strategies in Sardinia and Tunisia

    NASA Astrophysics Data System (ADS)

    Bird, Neil; Benabdallah, Sihem; Gouda, Nadine; Hummel, Franz; La Jeunesse, Isabelle; Meyer, Swen; Soddu, Antonino; Woess-Gallasch, Susanne

    2014-05-01

    A work package in the FP-7 funded CLIMB Project - Climate Induced Changes on the Hydrology of Mediterranean Basins Reducing Uncertainty and Quantifying Risk through an Integrated Monitoring and Modeling System had the goal of assessing socioeconomic vulnerability in two super-sites in future climates (2040-2070). The work package had deliverables to describe of agricultural adaptation measures appropriate to each site under future water availability scenarios and assess the risk of income losses due to water shortages in agriculture. The FAO model AQUACROP was used to estimate losses of agricultural productivity and indicate possible adaptation strategies. The presentation will focus on two interesting crops which show extreme vulnerability to expected changes in climate; irrigated lettuce in Sardinia and irrigated tomatoes in Tunisia. Modelling methodology, results and possible adaptation strategies will be presented.

  8. A source reconstruction algorithm based on adaptive hp-FEM for bioluminescence tomography.

    PubMed

    Han, Runqiang; Liang, Jimin; Qu, Xiaochao; Hou, Yanbin; Ren, Nunu; Mao, Jingjing; Tian, Jie

    2009-08-17

    As a novel modality of molecular imaging, bioluminescence tomography (BLT) is used to in vivo observe and measure the biological process at cellular and molecular level in small animals. The core issue of BLT is to determine the distribution of internal bioluminescent sources from optical measurements on external surface. In this paper, a new algorithm is presented for BLT source reconstruction based on adaptive hp-finite element method. Using adaptive mesh refinement strategy and intelligent permissible source region, we can obtain more accurate information about the location and density of sources, with the robustness, stability and efficiency improved. Numerical simulations and physical experiment were both conducted to verify the performance of the proposed algorithm, where the optical data on phantom surface were obtained via Monte Carlo simulation and CCD camera detection, respectively. The results represent the merits and potential of our algorithm for BLT source reconstruction.

  9. Adapting biomodulatory strategies for treatment in new contexts: pancreatic and oral cancers (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Anbil, Sriram R.; Rizvi, Imran; Khan, Amjad P.; Celli, Jonathan P.; Maytin, Edward V.; Hasan, Tayyaba

    2016-03-01

    Biomodulation of cancer cell metabolism represents a promising approach to overcome tumor heterogeneity and poor selectivity, which contribute significantly to treatment resistance. To date, several studies have demonstrated that modulation of cell metabolism including the heme synthesis pathway serves as an elegant approach to improve the efficacy of aminolevulinic acid (ALA) based photodynamic therapy (PDT). However, the ability of biomodulation-enhanced PDT to improve outcomes in low resource settings and to address challenges in treating lethal tumors with exogenous photosensitizers remains underexplored. The ability of vitamin D or methotrexate to enhance PDT efficacy in a carcinogen-induced hamster cheek pouch model of oral squamous cell carcinoma and in 3D cell-based models for pancreatic ductal adenocarcinoma is evaluated. Challenges associated with adapting PDT regimens to low resource settings, understanding the effects of biomodulatory agents on the metabolism of cancer cells, and the differential effects of biomodulatory agents on tumor and stromal cells will be discussed.

  10. Adaptive image contrast enhancement algorithm for point-based rendering

    NASA Astrophysics Data System (ADS)

    Xu, Shaoping; Liu, Xiaoping P.

    2015-03-01

    Surgical simulation is a major application in computer graphics and virtual reality, and most of the existing work indicates that interactive real-time cutting simulation of soft tissue is a fundamental but challenging research problem in virtual surgery simulation systems. More specifically, it is difficult to achieve a fast enough graphic update rate (at least 30 Hz) on commodity PC hardware by utilizing traditional triangle-based rendering algorithms. In recent years, point-based rendering (PBR) has been shown to offer the potential to outperform the traditional triangle-based rendering in speed when it is applied to highly complex soft tissue cutting models. Nevertheless, the PBR algorithms are still limited in visual quality due to inherent contrast distortion. We propose an adaptive image contrast enhancement algorithm as a postprocessing module for PBR, providing high visual rendering quality as well as acceptable rendering efficiency. Our approach is based on a perceptible image quality technique with automatic parameter selection, resulting in a visual quality comparable to existing conventional PBR algorithms. Experimental results show that our adaptive image contrast enhancement algorithm produces encouraging results both visually and numerically compared to representative algorithms, and experiments conducted on the latest hardware demonstrate that the proposed PBR framework with the postprocessing module is superior to the conventional PBR algorithm and that the proposed contrast enhancement algorithm can be utilized in (or compatible with) various variants of the conventional PBR algorithm.

  11. Combined use of leaf size and economics traits allows direct comparison of hydrophyte and terrestrial herbaceous adaptive strategies

    PubMed Central

    Pierce, Simon; Brusa, Guido; Sartori, Matteo; Cerabolini, Bruno E. L.

    2012-01-01

    Background and Aims Hydrophytes generally exhibit highly acquisitive leaf economics. However, a range of growth forms is evident, from small, free-floating and rapidly growing Lemniden to large, broad-leaved Nymphaeiden, denoting variability in adaptive strategies. Traits used to classify adaptive strategies in terrestrial species, such as canopy height, are not applicable to hydrophytes. We hypothesize that hydrophyte leaf size traits and economics exhibit sufficient overlap with terrestrial species to allow a common classification of plant functional types, sensu Grime's CSR theory. Methods Leaf morpho-functional traits were measured for 61 species from 47 water bodies in lowland continental, sub-alpine and alpine bioclimatic zones in southern Europe and compared against the full leaf economics spectrum and leaf size range of terrestrial herbs, and between hydrophyte growth forms. Key Results Hydrophytes differed in the ranges and mean values of traits compared with herbs, but principal components analysis (PCA) demonstrated that both groups shared axes of trait variability: PCA1 encompassed size variation (area and mass), and PCA2 ranged from relatively dense, carbon-rich leaves to nitrogen-rich leaves of high specific leaf area (SLA). Most growth forms exhibited trait syndromes directly equivalent to herbs classified as R adapted, although Nymphaeiden ranged between C and SR adaptation. Conclusions Our findings support the hypothesis that hydrophyte adaptive strategy variation reflects fundamental trade-offs in economics and size that govern all plants, and that hydrophyte adaptive strategies can be directly compared with terrestrial species by combining leaf economics and size traits. PMID:22337079

  12. Advances in Patch-Based Adaptive Mesh Refinement Scalability

    SciTech Connect

    Gunney, Brian T.N.; Anderson, Robert W.

    2015-12-18

    Patch-based structured adaptive mesh refinement (SAMR) is widely used for high-resolution simu- lations. Combined with modern supercomputers, it could provide simulations of unprecedented size and resolution. A persistent challenge for this com- bination has been managing dynamically adaptive meshes on more and more MPI tasks. The dis- tributed mesh management scheme in SAMRAI has made some progress SAMR scalability, but early al- gorithms still had trouble scaling past the regime of 105 MPI tasks. This work provides two critical SAMR regridding algorithms, which are integrated into that scheme to ensure efficiency of the whole. The clustering algorithm is an extension of the tile- clustering approach, making it more flexible and efficient in both clustering and parallelism. The partitioner is a new algorithm designed to prevent the network congestion experienced by its prede- cessor. We evaluated performance using weak- and strong-scaling benchmarks designed to be difficult for dynamic adaptivity. Results show good scaling on up to 1.5M cores and 2M MPI tasks. Detailed timing diagnostics suggest scaling would continue well past that.

  13. Advances in Patch-Based Adaptive Mesh Refinement Scalability

    DOE PAGES

    Gunney, Brian T.N.; Anderson, Robert W.

    2015-12-18

    Patch-based structured adaptive mesh refinement (SAMR) is widely used for high-resolution simu- lations. Combined with modern supercomputers, it could provide simulations of unprecedented size and resolution. A persistent challenge for this com- bination has been managing dynamically adaptive meshes on more and more MPI tasks. The dis- tributed mesh management scheme in SAMRAI has made some progress SAMR scalability, but early al- gorithms still had trouble scaling past the regime of 105 MPI tasks. This work provides two critical SAMR regridding algorithms, which are integrated into that scheme to ensure efficiency of the whole. The clustering algorithm is an extensionmore » of the tile- clustering approach, making it more flexible and efficient in both clustering and parallelism. The partitioner is a new algorithm designed to prevent the network congestion experienced by its prede- cessor. We evaluated performance using weak- and strong-scaling benchmarks designed to be difficult for dynamic adaptivity. Results show good scaling on up to 1.5M cores and 2M MPI tasks. Detailed timing diagnostics suggest scaling would continue well past that.« less

  14. An extended framework for adaptive playback-based video summarization

    NASA Astrophysics Data System (ADS)

    Peker, Kadir A.; Divakaran, Ajay

    2003-11-01

    In our previous work, we described an adaptive fast playback framework for video summarization where we changed the playback rate using the motion activity feature so as to maintain a constant "pace." This method provides an effective way of skimming through video, especially when the motion is not too complex and the background is mostly still, such as in surveillance video. In this paper, we present an extended summarization framework that, in addition to motion activity, uses semantic cues such as face or skin color appearance, speech and music detection, or other domain dependent semantically significant events to control the playback rate. The semantic features we use are computationally inexpensive and can be computed in compressed domain, yet are robust, reliable, and have a wide range of applicability across different content types. The presented framework also allows for adaptive summaries based on preference, for example, to include more dramatic vs. action elements, or vice versa. The user can switch at any time between the skimming and the normal playback modes. The continuity of the video is preserved, and complete omission of segments that may be important to the user is avoided by using adaptive fast playback instead of skipping over long segments. The rule-set and the input parameters can be further modified to fit a certain domain or application. Our framework can be used by itself, or as a subsequent presentation stage for a summary produced by any other summarization technique that relies on generating a sub-set of the content.

  15. Adaptive livelihood strategies for coping with water scarcity in the drylands of central Tanzania

    NASA Astrophysics Data System (ADS)

    Liwenga, Emma T.

    In this paper, it is argued that local knowledge for adapting to water scarcity is important for integrated resource management by taking into consideration both the natural and social constraints in a particular setting based on accumulated experience. The paper examines the relevance of local knowledge in sustaining agricultural production in the semiarid areas of central Tanzania. The paper specifically focuses on how water scarcity, as the major limiting factor, is addressed in the study area using local knowledge to sustain livelihoods of its people. The study was conducted in four villages; Mzula, Ilolo, Chanhumba and Ngahelezi, situation in Mvumi Division in Dodoma Region. The study mainly employed qualitative data collection techniques. Participatory methods provided a means of exploring perceptions and gaining deeper insights regarding natural resource utilization in terms of problems and opportunities. The main data sources drawn upon in this study were documentation, group interviews and field observations. Group interviews involved discussions with a group of 6-12 people selected on the basis of gender, age and socio-economic groups. Data analysis entailed structural and content analysis within the adaptive livelihood framework in relation to management of water scarcity using local knowledge. The findings confirm that rainfall is the main limiting factor for agricultural activities in the drylands of Central Tanzania. As such, local communities have developed, through time, indigenous knowledge to cope with such environments utilizing seasonality and diversity of landscapes. Use of this local knowledge is therefore effective in managing water scarcity by ensuring a continuous production of crops throughout the year. This practice implies increased food availability and accessibility through sales of such agricultural products. Local innovations for water management, such as cultivation in sandy rivers, appear to be very important means of accessing

  16. The evolution of alternative adaptive strategies for effective communication in noisy environments.

    PubMed

    Ord, Terry J; Charles, Grace K; Hofer, Rebecca K

    2011-01-01

    Animals communicating socially are expected to produce signals that are conspicuous within the habitats in which they live. The particular way in which a species adapts to its environment will depend on its ancestral condition and evolutionary history. At this point, it is unclear how properties of the environment and historical factors interact to shape communication. Tropical Anolis lizards advertise territorial ownership using visual displays in habitats where visual motion or "noise" from windblown vegetation poses an acute problem for the detection of display movements. We studied eight Anolis species that live in similar noise environments but belong to separate island radiations with divergent evolutionary histories. We found that species on Puerto Rico displayed at times when their signals were more likely to be detected by neighboring males and females (during periods of low noise). In contrast, species on Jamaica displayed irrespective of the level of environmental motion, apparently because these species have a display that is effective in a range of viewing conditions. Our findings appear to reflect a case of species originating from different evolutionary starting points evolving different signal strategies for effective communication in noisy environments. PMID:21117941

  17. A Pilot SMART for Developing an Adaptive Treatment Strategy for Adolescent Depression.

    PubMed

    Gunlicks-Stoessel, Meredith; Mufson, Laura; Westervelt, Ana; Almirall, Daniel; Murphy, Susan

    2016-01-01

    This pilot study was conducted to assess the feasibility and acceptability of 4 adaptive treatment strategies (ATSs) for adolescent depression to plan for a subsequent full-scale clinical trial. The ATSs aim to address 2 questions that arise when personalizing treatment: (a) For adolescents treated with Interpersonal Psychotherapy for depressed adolescents (IPT-A; Mufson et al., 2004 ), at what time point should therapists make the determination that the adolescent is not likely to respond if the initial treatment plan is continued (week 4 or week 8)? (b) For adolescents who are judged to need their treatment augmented, should the therapist increase the number of IPT-A sessions or add pharmacotherapy (fluoxetine)? A 16-week pilot sequential multiple assignment randomized trial (SMART) was conducted with 32 adolescents (M age = 14.9) who had a diagnosis of major depressive disorder, dysthymic disorder, or depressive disorder not otherwise specified. Adolescents were primarily female (75%) and Caucasian (84.4%). Data regarding the feasibility and acceptability of the study and treatment procedures and treatment response rates were collected. Week 4 was the more feasible and acceptable decision point for assessing need for a change to treatment. Adolescents, parents, and therapists reported a range of attitudes about medication and more intensive therapy as treatment options. Results from the pilot study have yielded additional research questions for the full-scale SMART and will improve our ability to successfully conduct the trial.

  18. Avoided heat-related mortality through climate adaptation strategies in three US cities.

    PubMed

    Stone, Brian; Vargo, Jason; Liu, Peng; Habeeb, Dana; DeLucia, Anthony; Trail, Marcus; Hu, Yongtao; Russell, Armistead

    2014-01-01

    Heat-related mortality in US cities is expected to more than double by the mid-to-late 21st century. Rising heat exposure in cities is projected to result from: 1) climate forcings from changing global atmospheric composition; and 2) local land surface characteristics responsible for the urban heat island effect. The extent to which heat management strategies designed to lessen the urban heat island effect could offset future heat-related mortality remains unexplored in the literature. Using coupled global and regional climate models with a human health effects model, we estimate changes in the number of heat-related deaths in 2050 resulting from modifications to vegetative cover and surface albedo across three climatically and demographically diverse US metropolitan areas: Atlanta, Georgia, Philadelphia, Pennsylvania, and Phoenix, Arizona. Employing separate health impact functions for average warm season and heat wave conditions in 2050, we find combinations of vegetation and albedo enhancement to offset projected increases in heat-related mortality by 40 to 99% across the three metropolitan regions. These results demonstrate the potential for extensive land surface changes in cities to provide adaptive benefits to urban populations at risk for rising heat exposure with climate change.

  19. Pseudomonas aeruginosa adapts its iron uptake strategies in function of the type of infections

    PubMed Central

    Cornelis, Pierre; Dingemans, Jozef

    2013-01-01

    Pseudomonas aeruginosa is a Gram-negative γ-Proteobacterium which is known for its capacity to colonize various niches, including some invertebrate and vertebrate hosts, making it one of the most frequent bacteria causing opportunistic infections. P. aeruginosa is able to cause acute as well as chronic infections and it uses different colonization and virulence factors to do so. Infections range from septicemia, urinary infections, burn wound colonization, and chronic colonization of the lungs of cystic fibrosis patients. Like the vast majority of organisms, P. aeruginosa needs iron to sustain growth. P. aeruginosa utilizes different strategies to take up iron, depending on the type of infection it causes. Two siderophores are produced by this bacterium, pyoverdine and pyochelin, characterized by high and low affinities for iron respectively. P. aeruginosa is also able to utilize different siderophores from other microorganisms (siderophore piracy). It can also take up heme from hemoproteins via two different systems. Under microaerobic or anaerobic conditions, P. aeruginosa is also able to take up ferrous iron via its Feo system using redox-cycling phenazines. Depending on the type of infection, P. aeruginosa can therefore adapt by switching from one iron uptake system to another as we will describe in this short review. PMID:24294593

  20. Evolution of the fruit endocarp: molecular mechanisms underlying adaptations in seed protection and dispersal strategies

    PubMed Central

    Dardick, Chris; Callahan, Ann M.

    2014-01-01

    Plant evolution is largely driven by adaptations in seed protection and dispersal strategies that allow diversification into new niches. This is evident by the tremendous variation in flowering and fruiting structures present both across and within different plant lineages. Within a single plant family a staggering variety of fruit types can be found such as fleshy fruits including berries, pomes, and drupes and dry fruit structures like achenes, capsules, and follicles. What are the evolutionary mechanisms that enable such dramatic shifts to occur in a relatively short period of time? This remains a fundamental question of plant biology today. On the surface it seems that these extreme differences in form and function must be the consequence of very different developmental programs that require unique sets of genes. Yet as we begin to decipher the molecular and genetic basis underlying fruit form it is becoming apparent that simple genetic changes in key developmental regulatory genes can have profound anatomical effects. In this review, we discuss recent advances in understanding the molecular mechanisms of fruit endocarp tissue differentiation that have contributed to species diversification within three plant lineages. PMID:25009543

  1. Designing antibiotic cycling strategies by determining and understanding local adaptive landscapes.

    PubMed

    Goulart, Christiane P; Mahmudi, Mentar; Crona, Kristina A; Jacobs, Stephen D; Kallmann, Marcelo; Hall, Barry G; Greene, Devin C; Barlow, Miriam

    2013-01-01

    The evolution of antibiotic resistance among bacteria threatens our continued ability to treat infectious diseases. The need for sustainable strategies to cure bacterial infections has never been greater. So far, all attempts to restore susceptibility after resistance has arisen have been unsuccessful, including restrictions on prescribing [1] and antibiotic cycling [2], [3]. Part of the problem may be that those efforts have implemented different classes of unrelated antibiotics, and relied on removal of resistance by random loss of resistance genes from bacterial populations (drift). Here, we show that alternating structurally similar antibiotics can restore susceptibility to antibiotics after resistance has evolved. We found that the resistance phenotypes conferred by variant alleles of the resistance gene encoding the TEM β-lactamase (bla(TEM)) varied greatly among 15 different β-lactam antibiotics. We captured those differences by characterizing complete adaptive landscapes for the resistance alleles bla(TEM-50) and bla(TEM-85), each of which differs from its ancestor bla(TEM-1) by four mutations. We identified pathways through those landscapes where selection for increased resistance moved in a repeating cycle among a limited set of alleles as antibiotics were alternated. Our results showed that susceptibility to antibiotics can be sustainably renewed by cycling structurally similar antibiotics. We anticipate that these results may provide a conceptual framework for managing antibiotic resistance. This approach may also guide sustainable cycling of the drugs used to treat malaria and HIV.

  2. Pseudomonas aeruginosa adapts its iron uptake strategies in function of the type of infections.

    PubMed

    Cornelis, Pierre; Dingemans, Jozef

    2013-01-01

    Pseudomonas aeruginosa is a Gram-negative γ-Proteobacterium which is known for its capacity to colonize various niches, including some invertebrate and vertebrate hosts, making it one of the most frequent bacteria causing opportunistic infections. P. aeruginosa is able to cause acute as well as chronic infections and it uses different colonization and virulence factors to do so. Infections range from septicemia, urinary infections, burn wound colonization, and chronic colonization of the lungs of cystic fibrosis patients. Like the vast majority of organisms, P. aeruginosa needs iron to sustain growth. P. aeruginosa utilizes different strategies to take up iron, depending on the type of infection it causes. Two siderophores are produced by this bacterium, pyoverdine and pyochelin, characterized by high and low affinities for iron respectively. P. aeruginosa is also able to utilize different siderophores from other microorganisms (siderophore piracy). It can also take up heme from hemoproteins via two different systems. Under microaerobic or anaerobic conditions, P. aeruginosa is also able to take up ferrous iron via its Feo system using redox-cycling phenazines. Depending on the type of infection, P. aeruginosa can therefore adapt by switching from one iron uptake system to another as we will describe in this short review. PMID:24294593

  3. Private adaptation strategies and implementation in flood risk management: why people do nothing?

    NASA Astrophysics Data System (ADS)

    Karagiorgos, Konstantinos; Thaler, Thomas; Maris, Fotios; Paparrizos, Spyros; Fuchs, Sven

    2015-04-01

    In the past decades, vulnerability assessment has emerged as an important field of research in flood risk management, in particular with respect to climate change and necessary adaptation strategies for the society. Probably starting with Chamber's seminal article on vulnerability, coping and policy (Chambers 1989), and further developed as the causal structure of vulnerability by Bohle (2001) and others, at least two research paradigms exist: an internal side focusing on societal resilience and coping capacities, and an external side targeted at a reduction of negative effects in terms of loss reduction (Fuchs 2009). Despite considerable research effects, however, different definitions and concepts still dominate the debate; it is surely that different scientific disciplines are working with this term: natural scientists, engineers, social scientists or economists, to name just a few. Each discipline defines vulnerability in a way which fits to their disciplinary purposes (Fuchs et al. 2011). But why has there been so little progress in our ability to adapt to flood hazards? White et al. (2001) summarised this paradox in an article with the title "Knowing better and losing even more - the use of knowledge in hazard management". One of the fundamental reasons for the lack of progress is the continuing separation of research on natural processes and socio-economic processes without considering interaction between these systems (Fuchs & Keiler 2013), as well as between scientific research results and the policy implementation (Medd & Marvin 2005). Moreover, as many studies were focused on the vulnerability of least developed societies to natural hazards (O'Brien et al. 2008), there is a particular lack in studies targeted at an implementation of existing adaptation frameworks at the level of highly-developed countries (Field et al. 2012; Scolobig et al. 2012). This gap results in a challenge for attempts to develop formal models into practical application and policy

  4. MTPA control of mechanical sensorless IPMSM based on adaptive nonlinear control.

    PubMed

    Najjar-Khodabakhsh, Abbas; Soltani, Jafar

    2016-03-01

    In this paper, an adaptive nonlinear control scheme has been proposed for implementing maximum torque per ampere (MTPA) control strategy corresponding to interior permanent magnet synchronous motor (IPMSM) drive. This control scheme is developed in the rotor d-q axis reference frame using adaptive input-output state feedback linearization (AIOFL) method. The drive system control stability is supported by Lyapunov theory. The motor inductances are online estimated by an estimation law obtained by AIOFL. The estimation errors of these parameters are proved to be asymptotically converged to zero. Based on minimizing the motor current amplitude, the MTPA control strategy is performed by using the nonlinear optimization technique while considering the online reference torque. The motor reference torque is generated by a conventional rotor speed PI controller. By performing MTPA control strategy, the generated online motor d-q reference currents were used in AIOFL controller to obtain the SV-PWM reference voltages and the online estimation of the motor d-q inductances. In addition, the stator resistance is online estimated using a conventional PI controller. Moreover, the rotor position is detected using the online estimation of the stator flux and online estimation of the motor q-axis inductance. Simulation and experimental results obtained prove the effectiveness and the capability of the proposed control method. PMID:26830002

  5. Bayesian integrated testing strategy (ITS) for skin sensitization potency assessment: a decision support system for quantitative weight of evidence and adaptive testing strategy.

    PubMed

    Jaworska, Joanna S; Natsch, Andreas; Ryan, Cindy; Strickland, Judy; Ashikaga, Takao; Miyazawa, Masaaki

    2015-12-01

    The presented Bayesian network Integrated Testing Strategy (ITS-3) for skin sensitization potency assessment is a decision support system for a risk assessor that provides quantitative weight of evidence, leading to a mechanistically interpretable potency hypothesis, and formulates adaptive testing strategy for a chemical. The system was constructed with an aim to improve precision and accuracy for predicting LLNA potency beyond ITS-2 (Jaworska et al., J Appl Toxicol 33(11):1353-1364, 2013) by improving representation of chemistry and biology. Among novel elements are corrections for bioavailability both in vivo and in vitro as well as consideration of the individual assays' applicability domains in the prediction process. In ITS-3 structure, three validated alternative assays, DPRA, KeratinoSens and h-CLAT, represent first three key events of the adverse outcome pathway for skin sensitization. The skin sensitization potency prediction is provided as a probability distribution over four potency classes. The probability distribution is converted to Bayes factors to: 1) remove prediction bias introduced by the training set potency distribution and 2) express uncertainty in a quantitative manner, allowing transparent and consistent criteria to accept a prediction. The novel ITS-3 database includes 207 chemicals with a full set of in vivo and in vitro data. The accuracy for predicting LLNA outcomes on the external test set (n = 60) was as follows: hazard (two classes)-100 %, GHS potency classification (three classes)-96 %, potency (four classes)-89 %. This work demonstrates that skin sensitization potency prediction based on data from three key events, and often less, is possible, reliable over broad chemical classes and ready for practical applications.

  6. Bayesian integrated testing strategy (ITS) for skin sensitization potency assessment: a decision support system for quantitative weight of evidence and adaptive testing strategy.

    PubMed

    Jaworska, Joanna S; Natsch, Andreas; Ryan, Cindy; Strickland, Judy; Ashikaga, Takao; Miyazawa, Masaaki

    2015-12-01

    The presented Bayesian network Integrated Testing Strategy (ITS-3) for skin sensitization potency assessment is a decision support system for a risk assessor that provides quantitative weight of evidence, leading to a mechanistically interpretable potency hypothesis, and formulates adaptive testing strategy for a chemical. The system was constructed with an aim to improve precision and accuracy for predicting LLNA potency beyond ITS-2 (Jaworska et al., J Appl Toxicol 33(11):1353-1364, 2013) by improving representation of chemistry and biology. Among novel elements are corrections for bioavailability both in vivo and in vitro as well as consideration of the individual assays' applicability domains in the prediction process. In ITS-3 structure, three validated alternative assays, DPRA, KeratinoSens and h-CLAT, represent first three key events of the adverse outcome pathway for skin sensitization. The skin sensitization potency prediction is provided as a probability distribution over four potency classes. The probability distribution is converted to Bayes factors to: 1) remove prediction bias introduced by the training set potency distribution and 2) express uncertainty in a quantitative manner, allowing transparent and consistent criteria to accept a prediction. The novel ITS-3 database includes 207 chemicals with a full set of in vivo and in vitro data. The accuracy for predicting LLNA outcomes on the external test set (n = 60) was as follows: hazard (two classes)-100 %, GHS potency classification (three classes)-96 %, potency (four classes)-89 %. This work demonstrates that skin sensitization potency prediction based on data from three key events, and often less, is possible, reliable over broad chemical classes and ready for practical applications. PMID:26612363

  7. Optimal adaptation of equivalent factor of equivalent consumption minimization strategy for fuel cell hybrid electric vehicles under active state inequality constraints

    NASA Astrophysics Data System (ADS)

    Han, Jihun; Park, Youngjin; Kum, Dongsuk

    2014-12-01

    Among existing energy management strategies (EMSs) for fuel cell hybrid electric vehicles (FCHEV), the equivalent consumption minimization strategy (ECMS) is often considered as a practical approach because it can be implemented in real-time, while achieving near-optimal performance. However, under real-world driving conditions with uncertainties such as hilly roads, both near-optimality and charge-sustenance of ECMS are not guaranteed unless the equivalent factor (EF) is optimally adjusted in real-time. In this paper, a methodology of extracting the globally optimal EF trajectory from dynamic programming (DP) solution is proposed for the design of EF adaptation strategies. In order to illustrate the performance and process of the extraction method, a FCHEV energy management problem under hilly road conditions is investigated as a case study. The main goal is to learn how EF should be adjusted and the impact of EF adaptation on fuel economy under several hilly road cases. Using the extraction method, the DP-based EF is computed, and its performance is compared with those of Pontryagin's minimum principle (PMP) and conventional ECMS. The results show that the optimal EF adaptation significantly improves fuel economy when the battery SoC constraint becomes active, and thus EF must be properly adjusted under severely hilly road conditions.

  8. Adaptive wavelet-based recognition of oscillatory patterns on electroencephalograms

    NASA Astrophysics Data System (ADS)

    Nazimov, Alexey I.; Pavlov, Alexey N.; Hramov, Alexander E.; Grubov, Vadim V.; Koronovskii, Alexey A.; Sitnikova, Evgenija Y.

    2013-02-01

    The problem of automatic recognition of specific oscillatory patterns on electroencephalograms (EEG) is addressed using the continuous wavelet-transform (CWT). A possibility of improving the quality of recognition by optimizing the choice of CWT parameters is discussed. An adaptive approach is proposed to identify sleep spindles (SS) and spike wave discharges (SWD) that assumes automatic selection of CWT-parameters reflecting the most informative features of the analyzed time-frequency structures. Advantages of the proposed technique over the standard wavelet-based approaches are considered.

  9. Digital speech enhancement based on DTOMP and adaptive quantile

    NASA Astrophysics Data System (ADS)

    Wang, Anna; Zhou, Xiaoxing; Xue, Changliang; Sun, Xiyan; Sun, Hongying

    2013-03-01

    Compressed Sensing (CS) that can effectively extract the information contained in the signal is a new sampling theory based on signal sparseness. This paper applies CS theory in digital speech signal enhancement processing, proposes an adaptive quantile method for the noise power estimation and combines the improved double-threshold orthogonal matching pursuit algorithm for speech reconstruction, then achieves speech enhancement processing. Compared with the simulation results of the spectral subtraction and the subspace algorithm, the experiment results verify the feasibility and effectiveness of the algorithm proposed in this paper applied to speech enhancement processing.

  10. Implementer-Initiated Adaptation of Evidence-Based Interventions: Kids Remember the Blue Wig

    ERIC Educational Resources Information Center

    Gibbs, D. A.; Krieger, K. E.; Cutbush, S. L.; Clinton-Sherrod, A. M.; Miller, S.

    2016-01-01

    Adaptation of evidence-based interventions by implementers is widespread. Although frequently viewed as departures from fidelity, adaptations may be positive in impact and consistent with fidelity. Research typically catalogs adaptations but rarely includes the implementers' perspectives on adaptation. We report data on individuals implementing an…

  11. Learners' Perceptions and Illusions of Adaptivity in Computer-Based Learning Environments

    ERIC Educational Resources Information Center

    Vandewaetere, Mieke; Vandercruysse, Sylke; Clarebout, Geraldine

    2012-01-01

    Research on computer-based adaptive learning environments has shown exemplary growth. Although the mechanisms of effective adaptive instruction are unraveled systematically, little is known about the relative effect of learners' perceptions of adaptivity in adaptive learning environments. As previous research has demonstrated that the learners'…

  12. Context-Aware Adaptation in Web-Based Groupware Systems

    NASA Astrophysics Data System (ADS)

    Pinheiro, Manuele Kirsch; Carrillo-Ramos, Angela; Villanova-Oliver, Marlène; Gensel, Jérôme; Berbers, Yolande

    In this chapter, we propose a context-aware filtering process for adapting content delivered to mobile users by Web-based Groupware Systems. This process is based on context-aware profiles, expressing mobile users preferences for particular situations they encounter when using these systems. These profiles, which are shared between members of a given community, are exploited by the adaptation process in order to select and organize the delivered information into several levels of detail, based on a progressive access model. By defining these profiles, we propose a filtering process that considers both the user's current context and the user's preferences for this context. The context notion of context is represented by an object-oriented model we propose and which takes into account consideration both the user's physical and collaborative context, including elements related to collaborative activities performed inside the groupware system. The filtering process selects, in a first step, the context-aware profiles that match the user's current context, and then it filters the available content according to the selected profiles and uses the progressive access model to organize the selected information.

  13. Fuzzy-based adaptive bandwidth control for loss guarantees.

    PubMed

    Siripongwutikorn, Peerapon; Banerjee, Sujata; Tipper, David

    2005-09-01

    This paper presents the use of adaptive bandwidth control (ABC) for a quantitative packet loss rate guarantee to aggregate traffic in packet switched networks. ABC starts with some initial amount of bandwidth allocated to a queue and adjusts it over time based on online measurements of system states to ensure that the allocated bandwidth is just enough to attain the specified loss requirement. Consequently, no a priori detailed traffic information is required, making ABC more suitable for efficient aggregate quality of service (QoS) provisioning. We propose an ABC algorithm called augmented Fuzzy (A-Fuzzy) control, whereby fuzzy logic control is used to keep an average queue length at an appropriate target value, and the measured packet loss rate is used to augment the standard control to achieve better performance. An extensive simulation study based on both theoretical traffic models and real traffic traces under a wide range of system configurations demonstrates that the A-Fuzzy control itself is highly robust, yields high bandwidth utilization, and is indeed a viable alternative and improvement to static bandwidth allocation (SBA) and existing adaptive bandwidth allocation schemes. Additionally, we develop a simple and efficient measurement-based admission control procedure which limits the amount of input traffic in order to maintain the performance of the A-Fuzzy control at an acceptable level.

  14. Robust observer-based adaptive fuzzy sliding mode controller

    NASA Astrophysics Data System (ADS)

    Oveisi, Atta; Nestorović, Tamara

    2016-08-01

    In this paper, a new observer-based adaptive fuzzy integral sliding mode controller is proposed based on the Lyapunov stability theorem. The plant is subjected to a square-integrable disturbance and is assumed to have mismatch uncertainties both in state- and input-matrices. Based on the classical sliding mode controller, the equivalent control effort is obtained to satisfy the sufficient requirement of sliding mode controller and then the control law is modified to guarantee the reachability of the system trajectory to the sliding manifold. In order to relax the norm-bounded constrains on the control law and solve the chattering problem of sliding mode controller, a fuzzy logic inference mechanism is combined with the controller. An adaptive law is then introduced to tune the parameters of the fuzzy system on-line. Finally, for evaluating the controller and the robust performance of the closed-loop system, the proposed regulator is implemented on a real-time mechanical vibrating system.

  15. Adapting an evidence-based survivorship intervention for Latina breast cancer survivors

    PubMed Central

    Meneses, Karen; Gisiger-Camata, Silvia; Schoenberger, Yu-Mei; Weech-Maldonado, Robert; McNees, Patrick

    2015-01-01

    Aim About 120,000 Latina breast cancer survivors (LBCS) live in the USA with the numbers expected to increase. LBCS experience survivorship disparities and report poor quality of life outcomes. Despite poor outcomes, few survivorship interventions for LBCS are available. Adapting evidence-based interventions for Latinas may be one strategy to reduce disparities. Materials & Methods An evidence-based intervention called the Breast Cancer Education Intervention was adapted for Latinas. First, certified translation and cognitive interview to assess cultural relevance were conducted. Next, a pilot sample of 40 Latinas who participated in the intervention were asked to provide follow-up evaluation of their satisfaction with and usefulness of the translated education manual and intervention. Results Thirty LBCS completed the intervention, and 14 LBCS submitted an evaluation summary expressing satisfaction with usefulness, readability and relevance. Conclusion The process by which translation and cultural adaptation of an evidence-based intervention provides beginning foundation to support and reduce disparities among LBCS. PMID:25776285

  16. Microscopic cell nuclei segmentation based on adaptive attention window.

    PubMed

    Ko, ByoungChul; Seo, MiSuk; Nam, Jae-Yeal

    2009-06-01

    This paper presents an adaptive attention window (AAW)-based microscopic cell nuclei segmentation method. For semantic AAW detection, a luminance map is used to create an initial attention window, which is then reduced close to the size of the real region of interest (ROI) using a quad-tree. The purpose of the AAW is to facilitate background removal and reduce the ROI segmentation processing time. Region segmentation is performed within the AAW, followed by region clustering and removal to produce segmentation of only ROIs. Experimental results demonstrate that the proposed method can efficiently segment one or more ROIs and produce similar segmentation results to human perception. In future work, the proposed method will be used for supporting a region-based medical image retrieval system that can generate a combined feature vector of segmented ROIs based on extraction and patient data.

  17. Adaptive fiber optics collimator based on flexible hinges.

    PubMed

    Zhi, Dong; Ma, Yanxing; Ma, Pengfei; Si, Lei; Wang, Xiaolin; Zhou, Pu

    2014-08-20

    In this manuscript, we present a new design for an adaptive fiber optics collimator (AFOC) based on flexible hinges by using piezoelectric stacks actuators for X-Y displacement. Different from traditional AFOC, the new structure is based on flexible hinges to drive the fiber end cap instead of naked fiber. We fabricated a real AFOC based on flexible hinges, and the end cap's deviation and resonance frequency of the device were measured. Experimental results show that this new AFOC can provide fast control of tip-tilt deviation of the laser beam emitting from the end cap. As a result, the fiber end cap can support much higher power than naked fiber, which makes the new structure ideal for tip-tilt controlling in a high-power fiber laser system.

  18. Community-based disaster preparedness and climate adaptation: local capacity-building in the Philippines.

    PubMed

    Allen, Katrina M

    2006-03-01

    Community-based disaster preparedness (CBDP) approaches are increasingly important elements of vulnerability reduction and disaster management strategies. They are associated with a policy trend that values the knowledge and capacities of local people and builds on local resources, including social capital. CBDP may be instrumental not only in formulating local coping and adaptation strategies, but also in situating them within wider development planning and debates. In theory, local people can be mobilised to resist unsustainable (vulnerability increasing) forms of development or livelihood practices and to raise local concerns more effectively with political representatives. This paper focuses on the potential of CBDP initiatives to alleviate vulnerability in the context of climate change, and their limitations. It presents evidence from the Philippines that, in the limited forms in which they are currently employed, CBDP initiatives have the potential both to empower and disempower, and warns against treating CBDP as a panacea to disaster management problems.

  19. An optimal dynamic inversion-based neuro-adaptive approach for treatment of chronic myelogenous leukemia.

    PubMed

    Padhi, Radhakant; Kothari, Mangal

    2007-09-01

    Combining the advanced techniques of optimal dynamic inversion and model-following neuro-adaptive control design, an innovative technique is presented to design an automatic drug administration strategy for effective treatment of chronic myelogenous leukemia (CML). A recently developed nonlinear mathematical model for cell dynamics is used to design the controller (medication dosage). First, a nominal controller is designed based on the principle of optimal dynamic inversion. This controller can treat the nominal model patients (patients who can be described by the mathematical model used here with the nominal parameter values) effectively. However, since the system parameters for a realistic model patient can be different from that of the nominal model patients, simulation studies for such patients indicate that the nominal controller is either inefficient or, worse, ineffective; i.e. the trajectory of the number of cancer cells either shows non-satisfactory transient behavior or it grows in an unstable manner. Hence, to make the drug dosage history more realistic and patient-specific, a model-following neuro-adaptive controller is augmented to the nominal controller. In this adaptive approach, a neural network trained online facilitates a new adaptive controller. The training process of the neural network is based on Lyapunov stability theory, which guarantees both stability of the cancer cell dynamics as well as boundedness of the network weights. From simulation studies, this adaptive control design approach is found to be very effective to treat the CML disease for realistic patients. Sufficient generality is retained in the mathematical developments so that the technique can be applied to other similar nonlinear control design problems as well.

  20. Adaptive marker-free registration using a multiple point strategy for real-time and robust endoscope electromagnetic navigation.

    PubMed

    Luo, Xiongbiao; Wan, Ying; He, Xiangjian; Mori, Kensaku

    2015-02-01

    Registration of pre-clinical images to physical space is indispensable for computer-assisted endoscopic interventions in operating rooms. Electromagnetically navigated endoscopic interventions are increasingly performed at current diagnoses and treatments. Such interventions use an electromagnetic tracker with a miniature sensor that is usually attached at an endoscope distal tip to real time track endoscope movements in a pre-clinical image space. Spatial alignment between the electromagnetic tracker (or sensor) and pre-clinical images must be performed to navigate the endoscope to target regions. This paper proposes an adaptive marker-free registration method that uses a multiple point selection strategy. This method seeks to address an assumption that the endoscope is operated along the centerline of an intraluminal organ which is easily violated during interventions. We introduce an adaptive strategy that generates multiple points in terms of sensor measurements and endoscope tip center calibration. From these generated points, we adaptively choose the optimal point, which is the closest to its assigned the centerline of the hollow organ, to perform registration. The experimental results demonstrate that our proposed adaptive strategy significantly reduced the target registration error from 5.32 to 2.59 mm in static phantoms validation, as well as from at least 7.58 mm to 4.71 mm in dynamic phantom validation compared to current available methods.

  1. Moving Past Curricula and Strategies: Language and the Development of Adaptive Pedagogy for Immersive Learning Environments

    NASA Astrophysics Data System (ADS)

    Hand, Brian; Cavagnetto, Andy; Chen, Ying-Chih; Park, Soonhye

    2016-04-01

    Given current concerns internationally about student performance in science and the need to shift how science is being learnt in schools, as a community, we need to shift how we approach the issue of learning and teaching in science. In the future, we are going to have to close the gap between how students construct and engage with knowledge in a media-rich environment, and how school classroom environments engage them. This is going to require a shift to immersive environments where attention is paid to the knowledge bases and resources students bring into the classroom. Teachers will have to adopt adaptive pedagogical approaches that are framed around a more nuanced understanding of epistemological orientation, language and the nature of prosocial environments.

  2. Regional and Household Adaptation Strategies to Climate Extremes: the Case Study of the Beava River Basin, the Czech Republic

    NASA Astrophysics Data System (ADS)

    Duží, Barbora; Stojanov, Robert; Vikhrov, Dmytro

    2013-04-01

    We investigate regional and household adaptation strategies in the region affected by climate extremes, focusing on floods occurrence during past 15 years period. The main research question is: What is the overall state of adaptation measurements to climate extremes on the Bečva river basin? Target area is located along upper and middle part of the Bečva river basin in the east of the Czech Republic. The main theoretical concepts draw from differentiations between coping/adaptation strategies to climate extremes and theory of focusing event as a starter of changes in attention and agenda of problem solution. We apply mixed empirical research and case study approach. First we use qualitative research to serve as an initial entrance to the issue, to find out the perception of adaptation progress and preparedness to climate extremes on regional level. We conducted deep interviews (N=20) with relevant stakeholders. We proceed with quantitative research through the conducting face-to face questionnaires with household residents (N=305) in no, low and no risk area in relation to flood occurrence. We designed set of questions to find out relation among experiences with flood, the level of damages and applied emergency and adaptation measurements.

  3. Divergent Adaptive Strategies by Two Co-occurring Epiphytic Orchids to Water Stress: Escape or Avoidance?

    PubMed

    Zhang, Wei; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    Due to the fluctuating water availability in the arboreal habitat, epiphytic plants are considered vulnerable to climate change and anthropogenic disturbances. Although co-occurring taxa have been observed divergent adaptive performances in response to drought, the underlying physiological and morphological mechanisms by which epiphyte species cope with water stress remain poorly understood. In the present study, two co-occurring epiphytic orchids with different phenologies were selected to investigate their drought-resistance performances. We compared their functional traits, and monitored their physiological performances in a 25-days of drought treatment. In contrast to the deciduous species Pleione albiflora, the evergreen species Coelogyne corymbosa had different root anatomical structures and higher values for saturated water content of pseudobulbs. Moreover, plants of C. corymbosa had thicker leaves and epidermis, denser veins and stomata, and higher values for leaf mass per unit area and the time required to dry saturated leaves to 70% relative water content. However, samples from that species had lower values for net photosynthetic rate (A n), stomatal length and chlorophyll content per unit dry mass. Nevertheless, due to greater capacity for water storage and conservation, C. corymbosa maintained higher A n, stomatal conductance (g s), and instantaneous water-use efficiency during severe drought period, and their values for leaf water potential were higher after the water stress treatment. By Day 10 after irrigation was restarted, only C. corymbosa plants recovered their values for A n and g s to levels close to those calculated prior to the imposition of water stress. Our results suggest that the different performance responding to drought and re-watering in two co-occurring epiphytic orchids is related to water-related traits and these two species have divergent adaptive mechanisms. Overall, C. corymbosa demonstrates drought avoidance by enhancing water

  4. Divergent Adaptive Strategies by Two Co-occurring Epiphytic Orchids to Water Stress: Escape or Avoidance?

    PubMed

    Zhang, Wei; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    Due to the fluctuating water availability in the arboreal habitat, epiphytic plants are considered vulnerable to climate change and anthropogenic disturbances. Although co-occurring taxa have been observed divergent adaptive performances in response to drought, the underlying physiological and morphological mechanisms by which epiphyte species cope with water stress remain poorly understood. In the present study, two co-occurring epiphytic orchids with different phenologies were selected to investigate their drought-resistance performances. We compared their functional traits, and monitored their physiological performances in a 25-days of drought treatment. In contrast to the deciduous species Pleione albiflora, the evergreen species Coelogyne corymbosa had different root anatomical structures and higher values for saturated water content of pseudobulbs. Moreover, plants of C. corymbosa had thicker leaves and epidermis, denser veins and stomata, and higher values for leaf mass per unit area and the time required to dry saturated leaves to 70% relative water content. However, samples from that species had lower values for net photosynthetic rate (A n), stomatal length and chlorophyll content per unit dry mass. Nevertheless, due to greater capacity for water storage and conservation, C. corymbosa maintained higher A n, stomatal conductance (g s), and instantaneous water-use efficiency during severe drought period, and their values for leaf water potential were higher after the water stress treatment. By Day 10 after irrigation was restarted, only C. corymbosa plants recovered their values for A n and g s to levels close to those calculated prior to the imposition of water stress. Our results suggest that the different performance responding to drought and re-watering in two co-occurring epiphytic orchids is related to water-related traits and these two species have divergent adaptive mechanisms. Overall, C. corymbosa demonstrates drought avoidance by enhancing water

  5. Divergent Adaptive Strategies by Two Co-occurring Epiphytic Orchids to Water Stress: Escape or Avoidance?

    PubMed Central

    Zhang, Wei; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    Due to the fluctuating water availability in the arboreal habitat, epiphytic plants are considered vulnerable to climate change and anthropogenic disturbances. Although co-occurring taxa have been observed divergent adaptive performances in response to drought, the underlying physiological and morphological mechanisms by which epiphyte species cope with water stress remain poorly understood. In the present study, two co-occurring epiphytic orchids with different phenologies were selected to investigate their drought-resistance performances. We compared their functional traits, and monitored their physiological performances in a 25-days of drought treatment. In contrast to the deciduous species Pleione albiflora, the evergreen species Coelogyne corymbosa had different root anatomical structures and higher values for saturated water content of pseudobulbs. Moreover, plants of C. corymbosa had thicker leaves and epidermis, denser veins and stomata, and higher values for leaf mass per unit area and the time required to dry saturated leaves to 70% relative water content. However, samples from that species had lower values for net photosynthetic rate (An), stomatal length and chlorophyll content per unit dry mass. Nevertheless, due to greater capacity for water storage and conservation, C. corymbosa maintained higher An, stomatal conductance (gs), and instantaneous water-use efficiency during severe drought period, and their values for leaf water potential were higher after the water stress treatment. By Day 10 after irrigation was restarted, only C. corymbosa plants recovered their values for An and gs to levels close to those calculated prior to the imposition of water stress. Our results suggest that the different performance responding to drought and re-watering in two co-occurring epiphytic orchids is related to water-related traits and these two species have divergent adaptive mechanisms. Overall, C. corymbosa demonstrates drought avoidance by enhancing water

  6. Adaptation strategies of endolithic chlorophototrophs to survive the hyperarid and extreme solar radiation environment of the Atacama Desert.

    PubMed

    Wierzchos, Jacek; DiRuggiero, Jocelyne; Vítek, Petr; Artieda, Octavio; Souza-Egipsy, Virginia; Škaloud, Pavel; Tisza, Michel; Davila, Alfonso F; Vílchez, Carlos; Garbayo, Inés; Ascaso, Carmen

    2015-01-01

    The Atacama Desert, northern Chile, is one of the driest deserts on Earth and, as such, a natural laboratory to explore the limits of life and the strategies evolved by microorganisms to adapt to extreme environments. Here we report the exceptional adaptation strategies of chlorophototrophic and eukaryotic algae, and chlorophototrophic and prokaryotic cyanobacteria to the hyperarid and extremely high solar radiation conditions occurring in this desert. Our approach combined several microscopy techniques, spectroscopic analytical methods, and molecular analyses. We found that the major adaptation strategy was to avoid the extreme environmental conditions by colonizing cryptoendolithic, as well as, hypoendolithic habitats within gypsum deposits. The cryptoendolithic colonization occurred a few millimeters beneath the gypsum surface and showed a succession of organized horizons of algae and cyanobacteria, which has never been reported for endolithic microbial communities. The presence of cyanobacteria beneath the algal layer, in close contact with sepiolite inclusions, and their hypoendolithic colonization suggest that occasional liquid water might persist within these sub-microhabitats. We also identified the presence of abundant carotenoids in the upper cryptoendolithic algal habitat and scytonemin in the cyanobacteria hypoendolithic habitat. This study illustrates that successful lithobiontic microbial colonization at the limit for microbial life is the result of a combination of adaptive strategies to avoid excess solar irradiance and extreme evapotranspiration rates, taking advantage of the complex structural and mineralogical characteristics of gypsum deposits-conceptually called "rock's habitable architecture." Additionally, self-protection by synthesis and accumulation of secondary metabolites likely produces a shielding effect that prevents photoinhibition and lethal photooxidative damage to the chlorophototrophs, representing another level of adaptation.

  7. Adaptation strategies of endolithic chlorophototrophs to survive the hyperarid and extreme solar radiation environment of the Atacama Desert.

    PubMed

    Wierzchos, Jacek; DiRuggiero, Jocelyne; Vítek, Petr; Artieda, Octavio; Souza-Egipsy, Virginia; Škaloud, Pavel; Tisza, Michel; Davila, Alfonso F; Vílchez, Carlos; Garbayo, Inés; Ascaso, Carmen

    2015-01-01

    The Atacama Desert, northern Chile, is one of the driest deserts on Earth and, as such, a natural laboratory to explore the limits of life and the strategies evolved by microorganisms to adapt to extreme environments. Here we report the exceptional adaptation strategies of chlorophototrophic and eukaryotic algae, and chlorophototrophic and prokaryotic cyanobacteria to the hyperarid and extremely high solar radiation conditions occurring in this desert. Our approach combined several microscopy techniques, spectroscopic analytical methods, and molecular analyses. We found that the major adaptation strategy was to avoid the extreme environmental conditions by colonizing cryptoendolithic, as well as, hypoendolithic habitats within gypsum deposits. The cryptoendolithic colonization occurred a few millimeters beneath the gypsum surface and showed a succession of organized horizons of algae and cyanobacteria, which has never been reported for endolithic microbial communities. The presence of cyanobacteria beneath the algal layer, in close contact with sepiolite inclusions, and their hypoendolithic colonization suggest that occasional liquid water might persist within these sub-microhabitats. We also identified the presence of abundant carotenoids in the upper cryptoendolithic algal habitat and scytonemin in the cyanobacteria hypoendolithic habitat. This study illustrates that successful lithobiontic microbial colonization at the limit for microbial life is the result of a combination of adaptive strategies to avoid excess solar irradiance and extreme evapotranspiration rates, taking advantage of the complex structural and mineralogical characteristics of gypsum deposits-conceptually called "rock's habitable architecture." Additionally, self-protection by synthesis and accumulation of secondary metabolites likely produces a shielding effect that prevents photoinhibition and lethal photooxidative damage to the chlorophototrophs, representing another level of adaptation

  8. Adaptation strategies of endolithic chlorophototrophs to survive the hyperarid and extreme solar radiation environment of the Atacama Desert

    PubMed Central

    Wierzchos, Jacek; DiRuggiero, Jocelyne; Vítek, Petr; Artieda, Octavio; Souza-Egipsy, Virginia; Škaloud, Pavel; Tisza, Michel; Davila, Alfonso F.; Vílchez, Carlos; Garbayo, Inés; Ascaso, Carmen

    2015-01-01

    The Atacama Desert, northern Chile, is one of the driest deserts on Earth and, as such, a natural laboratory to explore the limits of life and the strategies evolved by microorganisms to adapt to extreme environments. Here we report the exceptional adaptation strategies of chlorophototrophic and eukaryotic algae, and chlorophototrophic and prokaryotic cyanobacteria to the hyperarid and extremely high solar radiation conditions occurring in this desert. Our approach combined several microscopy techniques, spectroscopic analytical methods, and molecular analyses. We found that the major adaptation strategy was to avoid the extreme environmental conditions by colonizing cryptoendolithic, as well as, hypoendolithic habitats within gypsum deposits. The cryptoendolithic colonization occurred a few millimeters beneath the gypsum surface and showed a succession of organized horizons of algae and cyanobacteria, which has never been reported for endolithic microbial communities. The presence of cyanobacteria beneath the algal layer, in close contact with sepiolite inclusions, and their hypoendolithic colonization suggest that occasional liquid water might persist within these sub-microhabitats. We also identified the presence of abundant carotenoids in the upper cryptoendolithic algal habitat and scytonemin in the cyanobacteria hypoendolithic habitat. This study illustrates that successful lithobiontic microbial colonization at the limit for microbial life is the result of a combination of adaptive strategies to avoid excess solar irradiance and extreme evapotranspiration rates, taking advantage of the complex structural and mineralogical characteristics of gypsum deposits—conceptually called “rock's habitable architecture.” Additionally, self-protection by synthesis and accumulation of secondary metabolites likely produces a shielding effect that prevents photoinhibition and lethal photooxidative damage to the chlorophototrophs, representing another level of

  9. Ecology of weaning among nomadic Turkana pastoralists of Kenya: maternal thinking, maternal behavior, and human adaptive strategies.

    PubMed

    Gray, S J

    1996-06-01

    Weaning of human children is a complex process involving the introduction of non-breast-milk foods, reduction in suckling activity, and eventual termination of breast feeding. Because the choice of strategies for each component of the weaning process depends on the operating environmental constraints, reproductive demands on women, and prevailing levels of infant and weanling mortality, it is appropriate to examine weaning practices as human adaptive strategies. Here, I examine the structure of weaning and maternal attitudes toward weaning among nomadic Turkana pastoralists from the perspective of human adaptation. Using retrospective and prospective data on breast feeding, the use of non-breast-milk foods, and the cessation of breast feeding. I identify ideal strategies as those defined by Turkana women. Real behavior in relation to weaning, however, deviates considerably from the ideal, and this deviation reflects adaptive responses to nutritional and disease risks to infants. Particular attention is given to problematic aspects of weaning practices in Turkana, such as premature introduction of non-breast-milk foods and abrupt termination of breast feeding, which have been shown to contribute to high infant and weanling mortality in populations in developing countries. These practices have evolved from the dual caretaking and childbearing role of women and the necessity of reconciling the needs of the breast-feeding child with the demands of the next pregnancy. As such, they represent rational strategies for enhancing reproductive success in this and other similarly stressful environments.

  10. Dosimetric and Radiobiological Consequences of Computed Tomography–Guided Adaptive Strategies for Intensity Modulated Radiation Therapy of the Prostate

    SciTech Connect

    Battista, Jerry J.; Johnson, Carol; Turnbull, David; Kempe, Jeff; Bzdusek, Karl; Van Dyk, Jacob; Bauman, Glenn

    2013-12-01

    Purpose: To examine a range of scenarios for image-guided adaptive radiation therapy of prostate cancer, including different schedules for megavoltage CT imaging, patient repositioning, and dose replanning. Methods and Materials: We simulated multifraction dose distributions with deformable registration using 35 sets of megavoltage CT scans of 13 patients. We computed cumulative dose–volume histograms, from which tumor control probabilities and normal tissue complication probabilities (NTCPs) for rectum were calculated. Five-field intensity modulated radiation therapy (IMRT) with 18-MV x-rays was planned to achieve an isocentric dose of 76 Gy to the clinical target volume (CTV). The differences between D{sub 95}, tumor control probability, V{sub 70Gy}, and NTCP for rectum, for accumulated versus planned dose distributions, were compared for different target volume sizes, margins, and adaptive strategies. Results: The CTV D{sub 95} for IMRT treatment plans, averaged over 13 patients, was 75.2 Gy. Using the largest CTV margins (10/7 mm), the D{sub 95} values accumulated over 35 fractions were within 2% of the planned value, regardless of the adaptive strategy used. For tighter margins (5 mm), the average D{sub 95} values dropped to approximately 73.0 Gy even with frequent repositioning, and daily replanning was necessary to correct this deficit. When personalized margins were applied to an adaptive CTV derived from the first 6 treatment fractions using the STAPLE (Simultaneous Truth and Performance Level Estimation) algorithm, target coverage could be maintained using a single replan 1 week into therapy. For all approaches, normal tissue parameters (rectum V{sub 70Gy} and NTCP) remained within acceptable limits. Conclusions: The frequency of adaptive interventions depends on the size of the CTV combined with target margins used during IMRT optimization. The application of adaptive target margins (<5 mm) to an adaptive CTV determined 1 week into therapy minimizes

  11. Widefield multiphoton microscopy with image-based adaptive optics

    NASA Astrophysics Data System (ADS)

    Chang, C.-Y.; Cheng, L.-C.; Su, H.-W.; Yen, W.-C.; Chen, S.-J.

    2012-10-01

    Unlike conventional multiphoton microscopy according to pixel by pixel point scanning, a widefield multiphoton microscope based on spatiotemporal focusing has been developed to provide fast optical sectioning images at a frame rate over 100 Hz. In order to overcome the aberrations of the widefield multiphoton microscope and the wavefront distortion from turbid biospecimens, an image-based adaptive optics system (AOS) was integrated. The feedback control signal of the AOS was acquired according to locally maximize image intensity, which were provided by the widefield multiphoton excited microscope, by using a hill climbing algorithm. Then, the control signal was utilized to drive a deformable mirror in such a way as to eliminate the aberration and distortion. A R6G-doped PMMA thin film is also increased by 3.7-fold. Furthermore, the TPEF image quality of 1 μm fluorescent beads sealed in agarose gel at different depths is improved.

  12. Optimization-based wavefront sensorless adaptive optics for multiphoton microscopy.

    PubMed

    Antonello, Jacopo; van Werkhoven, Tim; Verhaegen, Michel; Truong, Hoa H; Keller, Christoph U; Gerritsen, Hans C

    2014-06-01

    Optical aberrations have detrimental effects in multiphoton microscopy. These effects can be curtailed by implementing model-based wavefront sensorless adaptive optics, which only requires the addition of a wavefront shaping device, such as a deformable mirror (DM) to an existing microscope. The aberration correction is achieved by maximizing a suitable image quality metric. We implement a model-based aberration correction algorithm in a second-harmonic microscope. The tip, tilt, and defocus aberrations are removed from the basis functions used for the control of the DM, as these aberrations induce distortions in the acquired images. We compute the parameters of a quadratic polynomial that is used to model the image quality metric directly from experimental input-output measurements. Finally, we apply the aberration correction by maximizing the image quality metric using the least-squares estimate of the unknown aberration.

  13. Adaptation to hot climate and strategies to alleviate heat stress in livestock production.

    PubMed

    Renaudeau, D; Collin, A; Yahav, S; de Basilio, V; Gourdine, J L; Collier, R J

    2012-05-01

    Despite many challenges faced by animal producers, including environmental problems, diseases, economic pressure, and feed availability, it is still predicted that animal production in developing countries will continue to sustain the future growth of the world's meat production. In these areas, livestock performance is generally lower than those obtained in Western Europe and North America. Although many factors can be involved, climatic factors are among the first and crucial limiting factors of the development of animal production in warm regions. In addition, global warming will further accentuate heat stress-related problems. The objective of this paper was to review the effective strategies to alleviate heat stress in the context of tropical livestock production systems. These strategies can be classified into three groups: those increasing feed intake or decreasing metabolic heat production, those enhancing heat-loss capacities, and those involving genetic selection for heat tolerance. Under heat stress, improved production should be possible through modifications of diet composition that either promotes a higher intake or compensates the low feed consumption. In addition, altering feeding management such as a change in feeding time and/or frequency, are efficient tools to avoid excessive heat load and improve survival rate, especially in poultry. Methods to enhance heat exchange between the environment and the animal and those changing the environment to prevent or limit heat stress can be used to improve performance under hot climatic conditions. Although differences in thermal tolerance exist between livestock species (ruminants > monogastrics), there are also large differences between breeds of a species and within each breed. Consequently, the opportunity may exist to improve thermal tolerance of the animals using genetic tools. However, further research is required to quantify the genetic antagonism between adaptation and production traits to evaluate

  14. 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.

  15. Automated Tract Extraction via Atlas Based Adaptive Clustering

    PubMed Central

    Tunç, Birkan; Parker, William A.; Ingalhalikar, Madhura; Verma, Ragini

    2014-01-01

    Advancements in imaging protocols such as the high angular resolution diffusion-weighted imaging (HARDI) and in tractography techniques are expected to cause an increase in the tract-based analyses. Statistical analyses over white matter tracts can contribute greatly towards understanding structural mechanisms of the brain since tracts are representative of the connectivity pathways. The main challenge with tract-based studies is the extraction of the tracts of interest in a consistent and comparable manner over a large group of individuals without drawing the inclusion and exclusion regions of interest. In this work, we design a framework for automated extraction of white matter tracts. The framework introduces three main components, namely a connectivity based fiber representation, a fiber clustering atlas, and a clustering approach called Adaptive Clustering. The fiber representation relies on the connectivity signatures of fibers to establish an easy correspondence between different subjects. A group-wise clustering of these fibers that are represented by the connectivity signatures is then used to generate a fiber bundle atlas. Finally, Adaptive Clustering incorporates the previously generated clustering atlas as a prior, to cluster the fibers of a new subject automatically. Experiments on the HARDI scans of healthy individuals acquired repeatedly, demonstrate the applicability, the reliability and the repeatability of our approach in extracting white matter tracts. By alleviating the seed region selection or the inclusion/exclusion ROI drawing requirements that are usually handled by trained radiologists, the proposed framework expands the range of possible clinical applications and establishes the ability to perform tract-based analyses with large samples. PMID:25134977

  16. Brain Based Instruction in Correctional Settings: Strategies for Teachers.

    ERIC Educational Resources Information Center

    Becktold, Toni Hill

    2001-01-01

    Brain-based learning strategies (learner choice, movement, small groups) may be inappropriate in corrections for security reasons. Problems encountered in correctional education (attention deficit disorder, learned helplessness) complicate the use of these strategies. Incorporating brain-based instruction in these settings requires creativity and…

  17. Human vulnerability to climate variability in the Sahel: farmers' adaptation strategies in northern Burkina Faso.

    PubMed

    Barbier, Bruno; Yacouba, Hamma; Karambiri, Harouna; Zoromé, Malick; Somé, Blaise

    2009-05-01

    In this study, the authors investigate farmers' vulnerability to climate variability and evaluate local adoption of technology and farmers' perceptions of adaptation strategies to rainfall variability and policies. A survey was conducted in a community in northern Burkina Faso following the crop failure of 2004. In 2006, following a better harvest, another survey was conducted to compare farmers' actions and reactions during two contrasted rainy seasons. The results confirm that farmers from this community have substantially changed their practices during the last few decades. They have adopted a wide range of techniques that are intended to simultaneously increase crop yield and reduce yield variability. Micro water harvesting (Zaï) techniques have been widely adopted (41%), and a majority of fields have been improved with stone lines (60%). Hay (48%) and sorghum residues are increasingly stored to feed animals during the dry season, making bull and sheep fattening now a common practice. Dry season vegetable production also involves a majority of the population (60%). According to farmers, most of the new techniques have been adopted because of growing land scarcity and new market opportunities, rather than because of climate variability. Population pressure has reached a critical threshold, while land scarcity, declining soil fertility and reduced animal mobility have pushed farmers to intensify agricultural production. These techniques reduce farmers' dependency on rainfall but are still insufficient to reduce poverty and vulnerability. Thirty-nine percent of the population remains vulnerable after a good rainy season. Despite farmers' desire to remain in their own communities, migrations are likely to remain a major source of regular income and form of recourse in the event of droughts.

  18. Human Vulnerability to Climate Variability in the Sahel: Farmers' Adaptation Strategies in Northern Burkina Faso

    NASA Astrophysics Data System (ADS)

    Barbier, Bruno; Yacouba, Hamma; Karambiri, Harouna; Zoromé, Malick; Somé, Blaise

    2009-05-01

    In this study, the authors investigate farmers’ vulnerability to climate variability and evaluate local adoption of technology and farmers’ perceptions of adaptation strategies to rainfall variability and policies. A survey was conducted in a community in northern Burkina Faso following the crop failure of 2004. In 2006, following a better harvest, another survey was conducted to compare farmers’ actions and reactions during two contrasted rainy seasons. The results confirm that farmers from this community have substantially changed their practices during the last few decades. They have adopted a wide range of techniques that are intended to simultaneously increase crop yield and reduce yield variability. Micro water harvesting (Zaï) techniques have been widely adopted (41%), and a majority of fields have been improved with stone lines (60%). Hay (48%) and sorghum residues are increasingly stored to feed animals during the dry season, making bull and sheep fattening now a common practice. Dry season vegetable production also involves a majority of the population (60%). According to farmers, most of the new techniques have been adopted because of growing land scarcity and new market opportunities, rather than because of climate variability. Population pressure has reached a critical threshold, while land scarcity, declining soil fertility and reduced animal mobility have pushed farmers to intensify agricultural production. These techniques reduce farmers’ dependency on rainfall but are still insufficient to reduce poverty and vulnerability. Thirty-nine percent of the population remains vulnerable after a good rainy season. Despite farmers’ desire to remain in their own communities, migrations are likely to remain a major source of regular income and form of recourse in the event of droughts.

  19. System-Based Strategies in Instructional Design.

    ERIC Educational Resources Information Center

    Dyman, Daniel J.

    The integration of concepts and contributions from learning theorists, media specialists, and teaching practitioners, optimized within a framework of selected system strategies derived from military management programs, can help resolve concerns for educational improvement and accountability and influence the utilization of technology enabling…

  20. Effectiveness and Tradeoffs between Portfolios of Adaptation Strategies Addressing Future Climate and Socioeconomic Uncertainties in California's Central Valley

    NASA Astrophysics Data System (ADS)

    Tansey, M. K.; Van Lienden, B.; Das, T.; Munevar, A.; Young, C. A.; Flores-Lopez, F.; Huntington, J. L.

    2013-12-01

    The Central Valley of California is one of the major agricultural areas in the United States. The Central Valley Project (CVP) is operated by the Bureau of Reclamation to serve multiple purposes including generating approximately 4.3 million gigawatt hours of hydropower and providing, on average, 5 million acre-feet of water per year to irrigate approximately 3 million acres of land in the Sacramento, San Joaquin, and Tulare Lake basins, 600,000 acre-feet per year of water for urban users, and 800,000 acre-feet of annual supplies for environmental purposes. The development of effective adaptation and mitigation strategies requires assessing multiple risks including potential climate changes as well as uncertainties in future socioeconomic conditions. In this study, a scenario-based analytical approach was employed by combining three potential 21st century socioeconomic futures with six representative climate and sea level change projections developed using a transient hybrid delta ensemble method from an archive of 112 bias corrected spatially downscaled CMIP3 global climate model simulations to form 18 future socioeconomic-climate scenarios. To better simulate the effects of climate changes on agricultural water demands, analyses of historical agricultural meteorological station records were employed to develop estimates of future changes in solar radiation and atmospheric humidity from the GCM simulated temperature and precipitation. Projected changes in atmospheric carbon dioxide were computed directly by weighting SRES emissions scenarios included in each representative climate projection. These results were used as inputs to a calibrated crop water use, growth and yield model to simulate the effects of climate changes on the evapotranspiration and yields of major crops grown in the Central Valley. Existing hydrologic, reservoir operations, water quality, hydropower, greenhouse gas (GHG) emissions and both urban and agricultural economic models were integrated

  1. An adaptive gyroscope-based algorithm for temporal gait analysis.

    PubMed

    Greene, Barry R; McGrath, Denise; O'Neill, Ross; O'Donovan, Karol J; Burns, Adrian; Caulfield, Brian

    2010-12-01

    Body-worn kinematic sensors have been widely proposed as the optimal solution for portable, low cost, ambulatory monitoring of gait. This study aims to evaluate an adaptive gyroscope-based algorithm for automated temporal gait analysis using body-worn wireless gyroscopes. Gyroscope data from nine healthy adult subjects performing four walks at four different speeds were then compared against data acquired simultaneously using two force plates and an optical motion capture system. Data from a poliomyelitis patient, exhibiting pathological gait walking with and without the aid of a crutch, were also compared to the force plate. Results show that the mean true error between the adaptive gyroscope algorithm and force plate was -4.5 ± 14.4 ms and 43.4 ± 6.0 ms for IC and TC points, respectively, in healthy subjects. Similarly, the mean true error when data from the polio patient were compared against the force plate was -75.61 ± 27.53 ms and 99.20 ± 46.00 ms for IC and TC points, respectively. A comparison of the present algorithm against temporal gait parameters derived from an optical motion analysis system showed good agreement for nine healthy subjects at four speeds. These results show that the algorithm reported here could constitute the basis of a robust, portable, low-cost system for ambulatory monitoring of gait.

  2. Adaptive multiwavelet-based watermarking through JPW masking.

    PubMed

    Cui, Lihong; Li, Wenguo

    2011-04-01

    In this paper, a multibit, multiplicative, spread spectrum watermarking using the discrete multiwavelet (including unbalanced and balanced multiwavelet) transform is presented. Performance improvement with respect to existing algorithm is obtained by means of a new just perceptual weighting (JPW) model. The new model incorporates various masking effects of human visual perception by taking into account the eye's sensitivity to noise changes depending on spatial frequency, luminance and texture of all the image subbands. In contrast to conventional JND threshold model, JPW describing minimum perceptual sensitivity weighting to noise changes, is fitter for nonadditive watermarking. Specifically, watermarking strength is adaptively adjusted to obtain minimum perceptual distortion by employing the JPW model. Correspondingly, an adaptive optimum decoding is derived using a statistic model based on generalized-Gaussian distribution (GGD) for multiwavelet coefficients of the cover-image. Furthermore, the impact of multiwavelet characteristics on proposed watermarking scheme is also analyzed. Finally, the experimental results show that proposed JPW model can improve the quality of the watermarked image and give more robustness of the watermark as compared with a variety of state-of-the-art algorithms.

  3. Lens-based wavefront sensorless adaptive optics swept source OCT

    PubMed Central

    Jian, Yifan; Lee, Sujin; Ju, Myeong Jin; Heisler, Morgan; Ding, Weiguang; Zawadzki, Robert J.; Bonora, Stefano; Sarunic, Marinko V.

    2016-01-01

    Optical coherence tomography (OCT) has revolutionized modern ophthalmology, providing depth resolved images of the retinal layers in a system that is suited to a clinical environment. Although the axial resolution of OCT system, which is a function of the light source bandwidth, is sufficient to resolve retinal features at a micrometer scale, the lateral resolution is dependent on the delivery optics and is limited by ocular aberrations. Through the combination of wavefront sensorless adaptive optics and the use of dual deformable transmissive optical elements, we present a compact lens-based OCT system at an imaging wavelength of 1060 nm for high resolution retinal imaging. We utilized a commercially available variable focal length lens to correct for a wide range of defocus commonly found in patient’s eyes, and a novel multi-actuator adaptive lens for aberration correction to achieve near diffraction limited imaging performance at the retina. With a parallel processing computational platform, high resolution cross-sectional and en face retinal image acquisition and display was performed in real time. In order to demonstrate the system functionality and clinical utility, we present images of the photoreceptor cone mosaic and other retinal layers acquired in vivo from research subjects. PMID:27278853

  4. Lens-based wavefront sensorless adaptive optics swept source OCT.

    PubMed

    Jian, Yifan; Lee, Sujin; Ju, Myeong Jin; Heisler, Morgan; Ding, Weiguang; Zawadzki, Robert J; Bonora, Stefano; Sarunic, Marinko V

    2016-01-01

    Optical coherence tomography (OCT) has revolutionized modern ophthalmology, providing depth resolved images of the retinal layers in a system that is suited to a clinical environment. Although the axial resolution of OCT system, which is a function of the light source bandwidth, is sufficient to resolve retinal features at a micrometer scale, the lateral resolution is dependent on the delivery optics and is limited by ocular aberrations. Through the combination of wavefront sensorless adaptive optics and the use of dual deformable transmissive optical elements, we present a compact lens-based OCT system at an imaging wavelength of 1060 nm for high resolution retinal imaging. We utilized a commercially available variable focal length lens to correct for a wide range of defocus commonly found in patient's eyes, and a novel multi-actuator adaptive lens for aberration correction to achieve near diffraction limited imaging performance at the retina. With a parallel processing computational platform, high resolution cross-sectional and en face retinal image acquisition and display was performed in real time. In order to demonstrate the system functionality and clinical utility, we present images of the photoreceptor cone mosaic and other retinal layers acquired in vivo from research subjects.

  5. Image quality-based adaptive illumination normalisation for face recognition

    NASA Astrophysics Data System (ADS)

    Sellahewa, Harin; Jassim, Sabah A.

    2009-05-01

    Automatic face recognition is a challenging task due to intra-class variations. Changes in lighting conditions during enrolment and identification stages contribute significantly to these intra-class variations. A common approach to address the effects such of varying conditions is to pre-process the biometric samples in order normalise intra-class variations. Histogram equalisation is a widely used illumination normalisation technique in face recognition. However, a recent study has shown that applying histogram equalisation on well-lit face images could lead to a decrease in recognition accuracy. This paper presents a dynamic approach to illumination normalisation, based on face image quality. The quality of a given face image is measured in terms of its luminance distortion by comparing this image against a known reference face image. Histogram equalisation is applied to a probe image if its luminance distortion is higher than a predefined threshold. We tested the proposed adaptive illumination normalisation method on the widely used Extended Yale Face Database B. Identification results demonstrate that our adaptive normalisation produces better identification accuracy compared to the conventional approach where every image is normalised, irrespective of the lighting condition they were acquired.

  6. Lens-based wavefront sensorless adaptive optics swept source OCT

    NASA Astrophysics Data System (ADS)

    Jian, Yifan; Lee, Sujin; Ju, Myeong Jin; Heisler, Morgan; Ding, Weiguang; Zawadzki, Robert J.; Bonora, Stefano; Sarunic, Marinko V.

    2016-06-01

    Optical coherence tomography (OCT) has revolutionized modern ophthalmology, providing depth resolved images of the retinal layers in a system that is suited to a clinical environment. Although the axial resolution of OCT system, which is a function of the light source bandwidth, is sufficient to resolve retinal features at a micrometer scale, the lateral resolution is dependent on the delivery optics and is limited by ocular aberrations. Through the combination of wavefront sensorless adaptive optics and the use of dual deformable transmissive optical elements, we present a compact lens-based OCT system at an imaging wavelength of 1060 nm for high resolution retinal imaging. We utilized a commercially available variable focal length lens to correct for a wide range of defocus commonly found in patient’s eyes, and a novel multi-actuator adaptive lens for aberration correction to achieve near diffraction limited imaging performance at the retina. With a parallel processing computational platform, high resolution cross-sectional and en face retinal image acquisition and display was performed in real time. In order to demonstrate the system functionality and clinical utility, we present images of the photoreceptor cone mosaic and other retinal layers acquired in vivo from research subjects.

  7. Adaptive enhancement method of infrared image based on scene feature

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao; Bai, Tingzhu; Shang, Fei

    2008-12-01

    All objects emit radiation in amounts related to their temperature and their ability to emit radiation. The infrared image shows the invisible infrared radiation emitted directly. Because of the advantages, the technology of infrared imaging is applied to many kinds of fields. But compared with visible image, the disadvantages of infrared image are obvious. The characteristics of low luminance, low contrast and the inconspicuous difference target and background are the main disadvantages of infrared image. The aim of infrared image enhancement is to improve the interpretability or perception of information in infrared image for human viewers, or to provide 'better' input for other automated image processing techniques. Most of the adaptive algorithm for image enhancement is mainly based on the gray-scale distribution of infrared image, and is not associated with the actual image scene of the features. So the pertinence of infrared image enhancement is not strong, and the infrared image is not conducive to the application of infrared surveillance. In this paper we have developed a scene feature-based algorithm to enhance the contrast of infrared image adaptively. At first, after analyzing the scene feature of different infrared image, we have chosen the feasible parameters to describe the infrared image. In the second place, we have constructed the new histogram distributing base on the chosen parameters by using Gaussian function. In the last place, the infrared image is enhanced by constructing a new form of histogram. Experimental results show that the algorithm has better performance than other methods mentioned in this paper for infrared scene images.

  8. An adaptive strategy for single- and multi-cluster gene assignment.

    PubMed

    Garg, Sanjeev; Hansen, Marc F; Rowe, David W; Achenie, Luke E K

    2003-01-01

    Strict assignment of genes to one class, dimensionality reduction, a priori specification of the number of classes, the need for a training set, nonunique solution, and complex learning mechanisms are some of the inadequacies of current clustering algorithms. Existing algorithms cluster genes on the basis of high positive correlations between their expression patterns. However, genes with strong negative correlations can also have similar functions and are most likely to have a role in the same pathways. To address some of these issues, we propose the adaptive centroid algorithm (ACA), which employs an analysis of variance (ANOVA)-based performance criterion. The ACA also uses Euclidian distances, the center-of-mass principle for heterogeneously distributed mass elements, and the given data set to give unique solutions. The proposed approach involves three stages. In the first stage a two-way ANOVA of the gene expression matrix is performed. The two factors in the ANOVA are gene expression and experimental condition. The residual mean squared error (MSE) from the ANOVA is used as a performance criterion in the ACA. Finally, correlated clusters are found based on the Pearson correlation coefficients. To validate the proposed approach, a two-way ANOVA is again performed on the discovered clusters. The results from this last step indicate that MSEs of the clusters are significantly lower compared to that of the fibroblast-serum gene expression matrix. The ACA is employed in this study for single- as well as multi-cluster gene assignments.

  9. Climate change adaptation & mitigation strategies for Water-Energy-Land Nexus management in Mediterranean region: Case study of Catalunya (Spain).

    NASA Astrophysics Data System (ADS)

    Kumar, Vikas; Schuhmacher, Marta

    2016-04-01

    Water-Energy-Land (WEL) Nexus management is one of those complex decision problems where holistic approach to supply-demand management considering different criteria would be valuable. However, multi-criteria decision making with diverse indicators measured on different scales and uncertainty levels is difficult to solve. On the other hand, climate adaptation and mitigation need to be integrated, and resource sensitive regions like Mediterranean provide ample opportunities towards that end. While the water sector plays a key role in climate adaptation, mitigation focuses on the energy and agriculture sector. Recent studies on the so-called WEL nexus confirm the potential synergies to be derived from mainstreaming climate adaptation in the water sector, while simultaneously addressing opportunities for co-management with energy (and also land use). Objective of this paper is to develop scenarios for the future imbalances in water & energy supply and demand for a water stressed Mediterranean area of Northern Spain (Catalonia) and to test the scenario based climate adaptation & mitigation strategy for WEL management policies. Resource sensitive area of Catalonia presents an interesting nexus problem to study highly stressed water demand scenario (representing all major demand sectors), very heterogeneous land use including intensive agriculture to diversified urban and industrial uses, and mixed energy supply including hydro, wind, gas turbine to nuclear energy. Different energy sectors have different water and land requirements. Inter-river basin water transfer is another factor which is considered for this area. The water-energy link is multifaceted. Energy production can affect water quality, while energy is used in water treatment and to reduce pollution. Similarly, hydropower - producing energy from water - and desalination - producing freshwater using energy - both play important role in economic growth by supplying large and secure amounts of 'green' energy or

  10. Understanding Inequalities of Maternal Smoking—Bridging the Gap with Adapted Intervention Strategies

    PubMed Central

    Boucher, Julie; Konkle, Anne T. M.

    2016-01-01

    Women who are generally part of socially disadvantaged and economically marginalized groups are especially susceptible to smoking during pregnancy but smoking rates are underreported in both research and interventions. While there is evidence to support the short-term efficacy of nicotine replacement therapy (NRT) use in pregnancy, long-term abstinence rates are modest. Current health strategies and interventions designed to diminish smoking in pregnancy have adopted a simplified approach to maternal smoking—one that suggests that they have a similar degree of choice to non-pregnant smokers regarding the avoidance of risk factors, and overlooks individual predictors of non-adherence. As a result, interventions have been ineffective among this high-risk group. For this reason, this paper addresses the multiple and interacting determinants that must be considered when developing and implementing effective strategies that lead to successful smoking cessation: socioeconomic status (SES), nicotine dependence, social support, culture, mental health, and health services. Based on our review of the literature, we conclude that tailoring cessation programs for pregnant smokers may ultimately optimize NRT efficacy and reduce the prevalence of maternal smoking. PMID:26959037

  11. Understanding Inequalities of Maternal Smoking--Bridging the Gap with Adapted Intervention Strategies.

    PubMed

    Boucher, Julie; Konkle, Anne T M

    2016-03-04

    Women who are generally part of socially disadvantaged and economically marginalized groups are especially susceptible to smoking during pregnancy but smoking rates are underreported in both research and interventions. While there is evidence to support the short-term efficacy of nicotine replacement therapy (NRT) use in pregnancy, long-term abstinence rates are modest. Current health strategies and interventions designed to diminish smoking in pregnancy have adopted a simplified approach to maternal smoking-one that suggests that they have a similar degree of choice to non-pregnant smokers regarding the avoidance of risk factors, and overlooks individual predictors of non-adherence. As a result, interventions have been ineffective among this high-risk group. For this reason, this paper addresses the multiple and interacting determinants that must be considered when developing and implementing effective strategies that lead to successful smoking cessation: socioeconomic status (SES), nicotine dependence, social support, culture, mental health, and health services. Based on our review of the literature, we conclude that tailoring cessation programs for pregnant smokers may ultimately optimize NRT efficacy and reduce the prevalence of maternal smoking.

  12. Adaptive wavefront sensor based on the Talbot phenomenon.

    PubMed

    Podanchuk, Dmytro V; Goloborodko, Andrey A; Kotov, Myhailo M; Kovalenko, Andrey V; Kurashov, Vitalij N; Dan'ko, Volodymyr P

    2016-04-20

    A new adaptive method of wavefront sensing is proposed and demonstrated. The method is based on the Talbot self-imaging effect, which is observed in an illuminating light beam with strong second-order aberration. Compensation of defocus and astigmatism is achieved with an appropriate choice of size of the rectangular unit cell of the diffraction grating, which is performed iteratively. A liquid-crystal spatial light modulator is used for this purpose. Self-imaging of rectangular grating in the astigmatic light beam is demonstrated experimentally. High-order aberrations are detected with respect to the compensated second-order aberration. The comparative results of wavefront sensing with a Shack-Hartmann sensor and the proposed sensor are adduced. PMID:27140122

  13. Age Estimation Based on Children's Voice: A Fuzzy-Based Decision Fusion Strategy

    PubMed Central

    Ting, Hua-Nong

    2014-01-01

    Automatic estimation of a speaker's age is a challenging research topic in the area of speech analysis. In this paper, a novel approach to estimate a speaker's age is presented. The method features a “divide and conquer” strategy wherein the speech data are divided into six groups based on the vowel classes. There are two reasons behind this strategy. First, reduction in the complicated distribution of the processing data improves the classifier's learning performance. Second, different vowel classes contain complementary information for age estimation. Mel-frequency cepstral coefficients are computed for each group and single layer feed-forward neural networks based on self-adaptive extreme learning machine are applied to the features to make a primary decision. Subsequently, fuzzy data fusion is employed to provide an overall decision by aggregating the classifier's outputs. The results are then compared with a number of state-of-the-art age estimation methods. Experiments conducted based on six age groups including children aged between 7 and 12 years revealed that fuzzy fusion of the classifier's outputs resulted in considerable improvement of up to 53.33% in age estimation accuracy. Moreover, the fuzzy fusion of decisions aggregated the complementary information of a speaker's age from various speech sources. PMID:25006595

  14. Cerebellar and Prefrontal Cortex Contributions to Adaptation, Strategies, and Reinforcement Learning

    PubMed Central

    Taylor, Jordan A.; Ivry, Richard B.

    2014-01-01

    Traditionally, motor learning has been studied as an implicit learning process, one in which movement errors are used to improve performance in a continuous, gradual manner. The cerebellum figures prominently in this literature given well-established ideas about the role of this system in error-based learning and the production of automatized skills. Recent developments have brought into focus the relevance of multiple learning mechanisms for sensorimotor learning. These include processes involving repetition, reinforcement learning, and strategy utilization. We examine these developments, considering their implications for understanding cerebellar function and how this structure interacts with other neural systems to support motor learning. Converging lines of evidence from behavioral, computational, and neuropsychological studies suggest a fundamental distinction between processes that use error information to improve action execution or action selection. While the cerebellum is clearly linked to the former, its role in the latter remains an open question. PMID:24916295

  15. Cerebellar and prefrontal cortex contributions to adaptation, strategies, and reinforcement learning.

    PubMed

    Taylor, Jordan A; Ivry, Richard B

    2014-01-01

    Traditionally, motor learning has been studied as an implicit learning process, one in which movement errors are used to improve performance in a continuous, gradual manner. The cerebellum figures prominently in this literature given well-established ideas about the role of this system in error-based learning and the production of automatized skills. Recent developments have brought into focus the relevance of multiple learning mechanisms for sensorimotor learning. These include processes involving repetition, reinforcement learning, and strategy utilization. We examine these developments, considering their implications for understanding cerebellar function and how this structure interacts with other neural systems to support motor learning. Converging lines of evidence from behavioral, computational, and neuropsychological studies suggest a fundamental distinction between processes that use error information to improve action execution or action selection. While the cerebellum is clearly linked to the former, its role in the latter remains an open question.

  16. Changing Minds with the Story of Adaptation: Strategies for Teaching Young Children about Natural Selection

    ERIC Educational Resources Information Center

    Emmons, Natalie; Smith, Hayley; Kelemen, Deborah

    2016-01-01

    Research Findings: Educational guidelines recommend a delayed, piecemeal approach to instruction on adaptation by natural selection. This approach is questionable given suggestions that older students' pervasive misunderstandings about adaptation are rooted in cognitive biases that develop early. In response to this, Kelemen et al. (2014) recently…

  17. A Strategy for Controlling Item Exposure in Multidimensional Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Lee, Yi-Hsuan; Ip, Edward H.; Fuh, Cheng-Der

    2008-01-01

    Although computerized adaptive tests have enjoyed tremendous growth, solutions for important problems remain unavailable. One problem is the control of item exposure rate. Because adaptive algorithms are designed to select optimal items, they choose items with high discriminating power. Thus, these items are selected more often than others,…

  18. Parallel level-set methods on adaptive tree-based grids

    NASA Astrophysics Data System (ADS)

    Mirzadeh, Mohammad; Guittet, Arthur; Burstedde, Carsten; Gibou, Frederic

    2016-10-01

    We present scalable algorithms for the level-set method on dynamic, adaptive Quadtree and Octree Cartesian grids. The algorithms are fully parallelized and implemented using the MPI standard and the open-source p4est library. We solve the level set equation with a semi-Lagrangian method which, similar to its serial implementation, is free of any time-step restrictions. This is achieved by introducing a scalable global interpolation scheme on adaptive tree-based grids. Moreover, we present a simple parallel reinitialization scheme using the pseudo-time transient formulation. Both parallel algorithms scale on the Stampede supercomputer, where we are currently using up to 4096 CPU cores, the limit of our current account. Finally, a relevant application of the algorithms is presented in modeling a crystallization phenomenon by solving a Stefan problem, illustrating a level of detail that would be impossible to achieve without a parallel adaptive strategy. We believe that the algorithms presented in this article will be of interest and useful to researchers working with the level-set framework and modeling multi-scale physics in general.

  19. Adapting evidence-based interventions using a common theory, practices, and principles.

    PubMed

    Rotheram-Borus, Mary Jane; Swendeman, Dallas; Becker, Kimberly D

    2014-01-01

    Hundreds of validated evidence-based intervention programs (EBIP) aim to improve families' well-being; however, most are not broadly adopted. As an alternative diffusion strategy, we created wellness centers to reach families' everyday lives with a prevention framework. At two wellness centers, one in a middle-class neighborhood and one in a low-income neighborhood, popular local activity leaders (instructors of martial arts, yoga, sports, music, dancing, Zumba), and motivated parents were trained to be Family Mentors. Trainings focused on a framework that taught synthesized, foundational prevention science theory, practice elements, and principles, applied to specific content areas (parenting, social skills, and obesity). Family Mentors were then allowed to adapt scripts and activities based on their cultural experiences but were closely monitored and supervised over time. The framework was implemented in a range of activities (summer camps, coaching) aimed at improving social, emotional, and behavioral outcomes. Successes and challenges are discussed for (a) engaging parents and communities; (b) identifying and training Family Mentors to promote children and families' well-being; and (c) gathering data for supervision, outcome evaluation, and continuous quality improvement. To broadly diffuse prevention to families, far more experimentation is needed with alternative and engaging implementation strategies that are enhanced with knowledge harvested from researchers' past 30 years of experience creating EBIP. One strategy is to train local parents and popular activity leaders in applying robust prevention science theory, common practice elements, and principles of EBIP. More systematic evaluation of such innovations is needed. PMID:24079747

  20. Adaptive Ripple Down Rules Method based on Description Length

    NASA Astrophysics Data System (ADS)

    Yoshida, Tetsuya; Wada, Takuya; Motoda, Hiroshi; Washio, Takashi

    A knowledge acquisition method Ripple Down Rules (RDR) can directly acquire and encode knowledge from human experts. It is an incremental acquisition method and each new piece of knowledge is added as an exception to the existing knowledge base. Past researches on RDR method assume that the problem domain is stable. This is not the case in reality, especially when an environment changes. Things change over time. This paper proposes an adaptive Ripple Down Rules method based on the Minimum Description Length Principle aiming at knowledge acquisition in a dynamically changing environment. We consider the change in the correspondence between attribute-values and class labels as a typical change in the environment. When such a change occurs, some pieces of knowledge previously acquired become worthless, and the existence of such knowledge may hinder acquisition of new knowledge. In our approach knowledge deletion is carried out as well as knowledge acquisition so that useless knowledge is properly discarded to ensure efficient knowledge acquisition while maintaining the prediction accuracy for future data. Furthermore, pruning is incorporated into the incremental knowledge acquisition in RDR to improve the prediction accuracy of the constructed knowledge base. Experiments were conducted by simulating the change in the correspondence between attribute-values and class labels using the datasets in UCI repository. The results are encouraging.

  1. Development of quantum-based adaptive neuro-fuzzy networks.

    PubMed

    Kim, Sung-Suk; Kwak, Keun-Chang

    2010-02-01

    In this study, we are concerned with a method for constructing quantum-based adaptive neuro-fuzzy networks (QANFNs) with a Takagi-Sugeno-Kang (TSK) fuzzy type based on the fuzzy granulation from a given input-output data set. For this purpose, we developed a systematic approach in producing automatic fuzzy rules based on fuzzy subtractive quantum clustering. This clustering technique is not only an extension of ideas inherent to scale-space and support-vector clustering but also represents an effective prototype that exhibits certain characteristics of the target system to be modeled from the fuzzy subtractive method. Furthermore, we developed linear-regression QANFN (LR-QANFN) as an incremental model to deal with localized nonlinearities of the system, so that all modeling discrepancies can be compensated. After adopting the construction of the linear regression as the first global model, we refined it through a series of local fuzzy if-then rules in order to capture the remaining localized characteristics. The experimental results revealed that the proposed QANFN and LR-QANFN yielded a better performance in comparison with radial basis function networks and the linguistic model obtained in previous literature for an automobile mile-per-gallon prediction, Boston Housing data, and a coagulant dosing process in a water purification plant.

  2. Climate change and waterborne diarrhoea in northern India: impacts and adaptation strategies.

    PubMed

    Moors, Eddy; Singh, Tanya; Siderius, Christian; Balakrishnan, Sneha; Mishra, Arabinda

    2013-12-01

    Although several studies show the vulnerability of human health to climate change, a clear comprehensive quantification of the increased health risks attributable to climate change is lacking. Even more complicated are assessments of adaptation measures for this sector. We discuss the impact of climate change on diarrhoea as a representative of a waterborne infectious disease affecting human health in the Ganges basin of northern India. A conceptual framework is presented for climate exposure response relationships based on studies from different countries, as empirical studies and appropriate epidemiological data sets for India are lacking. Four climate variables are included: temperature, increased/extreme precipitation, decreased precipitation/droughts and relative humidity. Applying the conceptual framework to the latest regional climate projections for northern India shows increases between present and future (2040s), varying spatially from no change to an increase of 21% in diarrhoea incidences, with 13.1% increase on average for the Ganges basin. We discuss three types of measures against diarrhoeal disease: reactive actions, preventive actions and national policy options. Preventive actions have the potential to counterbalance this expected increase. However, given the limited progress in reducing incidences over the past decade consorted actions and effective implementation and integration of existing policies are needed.

  3. Comparative and quantitative proteomics reveal the adaptive strategies of oyster larvae to ocean acidification.

    PubMed

    Dineshram, R; Quan, Q; Sharma, Rakesh; Chandramouli, Kondethimmanahalli; Yalamanchili, Hari Krishna; Chu, Ivan; Thiyagarajan, Vengatesen

    2015-12-01

    Decreasing pH due to anthropogenic CO2 inputs, called ocean acidification (OA), can make coastal environments unfavorable for oysters. This is a serious socioeconomical issue for China which supplies >70% of the world's edible oysters. Here, we present an iTRAQ-based protein profiling approach for the detection and quantification of proteome changes under OA in the early life stage of a commercially important oyster, Crassostrea hongkongensis. Availability of complete genome sequence for the pacific oyster (Crassostrea gigas) enabled us to confidently quantify over 1500 proteins in larval oysters. Over 7% of the proteome was altered in response to OA at pHNBS 7.6. Analysis of differentially expressed proteins and their associated functional pathways showed an upregulation of proteins involved in calcification, metabolic processes, and oxidative stress, each of which may be important in physiological adaptation of this species to OA. The downregulation of cytoskeletal and signal transduction proteins, on the other hand, might have impaired cellular dynamics and organelle development under OA. However, there were no significant detrimental effects in developmental processes such as metamorphic success. Implications of the differentially expressed proteins and metabolic pathways in the development of OA resistance in oyster larvae are discussed. The MS proteomics data have been deposited to the ProteomeXchange with identifiers PXD002138 (http://proteomecentral.proteomexchange.org/dataset/PXD002138).

  4. Beyond products: services-based strategy.

    PubMed

    Quinn, J B; Doorley, T L; Paquette, P C

    1990-01-01

    Services technologies are changing the way companies in every industry--manufacturers and service providers alike--compete. Vertical integration, physical facilities, even a seemingly superior product can no longer assure a competitive edge. Instead, sustainable advantage is more and more likely to come from developing superior capabilities in a few core service skills--and out-sourcing as much of the rest as possible. Within companies, technology is increasing the leverage of service activities: today, more value added comes from design innovations, product image, or other attributes that services create than from the production process. New technologies also let independent enterprises provide world-class services at lower costs than customers could achieve if they performed the activities themselves. These changes have far-reaching implications for how managers structure their organizations and define strategic focus. Companies like Apple, Honda, and Merck show that a less integrated but more focused organization is key to competitive success. They build their strategies around a few highly developed capabilities. And they outsource as many of the other activities in their value chain as possible. To help managers develop an activity-focused strategy, the authors offer a new way to approach competitive analyses, guidelines for determining which activities to outsource and which to retain, and an overview of the risks and rewards of strategic outsourcing. Throughout, they draw on the findings of their three-year study of the major impacts technology has had in the service sector.

  5. Offline multiple adaptive planning strategy for concurrent irradiation of the prostate and pelvic lymph nodes

    SciTech Connect

    Qi, Peng; Xia, Ping; Pouliot, Jean; Roach, Mack

    2014-02-15

    Purpose: Concurrent irradiation of the prostate and pelvic lymph nodes (PLNs) can be challenging due to the independent motion of the two target volumes. To address this challenge, the authors have proposed a strategy referred to as Multiple Adaptive Planning (MAP). To minimize the number of MAP plans, the authors’ previous work only considered the prostate motion in one major direction. After analyzing the pattern of the prostate motion, the authors investigated a practical number of intensity-modulated radiotherapy (IMRT) plans needed to accommodate the prostate motion in two major directions simultaneously. Methods: Six patients, who received concurrent irradiation of the prostate and PLNs, were selected for this study. Nine MAP-IMRT plans were created for each patient with nine prostate contours that represented the prostate at nine locations with respect to the PLNs, including the original prostate contour and eight contours shifted either 5 mm in a single anterior-posterior (A-P), or superior-inferior (S-I) direction, or 5 mm in both A-P and S-I directions simultaneously. From archived megavoltage cone beam CT (MV-CBCT) and a dual imaging registration, 17 MV-CBCTs from 33 available MV-CBCT from these patients showed large prostate displacements (>3 mm in any direction) with respect to the pelvic bones. For each of these 17 fractions, one of nine MAP-IMRT plans was retrospectively selected and applied to the MV-CBCT for dose calculation. For comparison, a simulated isocenter-shifting plan and a reoptimized plan were also created for each of these 17 fractions. The doses to 95% (D95) of the prostate and PLNs, and the doses to 5% (D5) of the rectum and bladder were calculated and analyzed. Results: For the prostate, D95 > 97% of the prescription dose was observed in 16, 16, and 17 of 17 fractions for the MAP, isocenter-shifted, and reoptimized plans, respectively. For PLNs, D95 > 97% of the prescription doses was observed in 10, 3, and 17 of 17 fractions for

  6. Quantification of Gram-positive bacteria: adaptation and evaluation of a preparation strategy using high amounts of clinical tissue

    PubMed Central

    2014-01-01

    Background A preparation method for quantification of bacteria in tissues is obligatory to reduce tissue mass, concentrate the target, purify, remove inhibitory substances and to achieve constant target recovery rates. No preparation method has been available until now for a high mass of tissue applicable for routine use and analytical veterinary diagnostics. Results This study describes an easy-to-use tissue preparation protocol to quantify Gram-positive bacteria from a large volume of tissue matrix. A previously published sample preparation method (Matrix-Lysis) from food science was successfully adapted for clinical use on tissues from pigs, including cerebrum, spinal cord, lung, liver, ileum, colon, caecum, kidney and muscle tissue. This tissue preparation method now permits quantification of pathogens from 5 g of organic matrix, which is a 20–200 fold increase by weight compared to other methods. It is based on solubilization of the sample matrix with either a chaotrope plus detergent or divalent salts as solubilization agents. The method was designed as a modular system, offering the possibility to change lysis buffers, according to tissue solubilization characteristics and the intended detection method (molecular or culture). Using Listeria monocytogenes as model organism, viable cell quantification or DNA extraction and quantitative real-time PCR were performed after Matrix-Lysis to determine recovery rates and detection limit (LOD). The adapted Matrix-Lysis protocol resulted in high recovery rates (mean value: 76% ± 39%) for all tested organs, except kidney, and recovery was constant over 5 log scales for all tested buffer systems. The LOD for Matrix-Lysis with subsequent plate count method (PCM) was as low as 1 CFU/5 g, while for qPCR based detection the LOD was 102 bacterial cell equivalents (BCE)/5 g for two buffer systems. Conclusions This tissue preparation is inexpensive and can be easily used for routine and analytical veterinary

  7. Cultural Adaptation and Implementation of Evidence-Based Parent-Training: A Systematic Review and Critique of Guiding Evidence

    PubMed Central

    Baumann, Ana A.; Powell, Byron J.; Kohl, Patricia L.; Tabak, Rachel G.; Penalba, Valentina; Proctor, Enola E.; Domenech-Rodriguez, Melanie M.; Cabassa, Leopoldo J.

    2015-01-01

    With advances in knowledge regarding efficacious evidence-based interventions, there have been significant attempts to culturally adapt, implement, and disseminate parent training interventions broadly, especially across ethnic and cultural groups. We sought to examine the extent to which researchers and developers of evidence-based parent training programs have used cultural adaptation models, tested implementation strategies, and evaluated implementation outcomes when integrating the interventions into routine care by conducting a systematic review of the literature for four evidence-based parent training interventions: Parent-Child Interaction Therapy (PCIT), The Incredible Years (IY), Parent Management Training-Oregon Model (PMTO™), and the Positive Parenting Program (Triple P). A total of 610 articles across the four programs were identified. Of those, only eight documented a rigorous cultural adaptation process, and only two sought to test the effectiveness of implementation strategies by using rigorous research designs. Our findings suggest that there is much work to be done to move parent-training intervention research towards a more rigorous examination of cultural adaptation and implementation practices. PMID:25960585

  8. Implementer-initiated adaptation of evidence-based interventions: kids remember the blue wig.

    PubMed

    Gibbs, D A; Krieger, K E; Cutbush, S L; Clinton-Sherrod, A M; Miller, S

    2016-06-01

    Adaptation of evidence-based interventions by implementers is widespread. Although frequently viewed as departures from fidelity, adaptations may be positive in impact and consistent with fidelity. Research typically catalogs adaptations but rarely includes the implementers' perspectives on adaptation. We report data on individuals implementing an evidence-based teen dating violence prevention curriculum. Key informant interviews (n = 20) and an online focus group (n = 10) addressed reasons for adaptations, adaptation processes and kinds of adaptations. All implementers described making adaptations, which they considered necessary to achieving intended outcomes. Adaptations were tailored to needs of individual students or learning opportunities presented by current events, fine-tuned over repeated applications and shared with colleagues. Adaptations modified both content and delivery and included both planned and in-the-moment changes. Implementers made adaptations to increase student engagement, and to fit students' learning needs, learning style, social maturity and culture. Student engagement served as an indicator that adaptation might be needed and provided feedback about the immediate effects of the adaptation. These findings underscore the value of fidelity assessments that measure participant response, intervention-specific guidance to implementers and evaluation of the impact of adaptations on participant response and intervention outcomes. PMID:27107432

  9. Toward a Common Understanding of Research-Based Instructional Strategies

    ERIC Educational Resources Information Center

    Goodwin, Deborah; Webb, Mary Ann

    2014-01-01

    A review of available books, articles and on-line resources which deal with "Research-Based Instructional Strategies" will produce a plethora of materials which promote the effectiveness of these strategies on student achievement. Also, a perusal of classroom instruction and teacher evaluation instruments will reveal that many of the…

  10. What Successful Science Teachers Do: 75 Research-Based Strategies

    ERIC Educational Resources Information Center

    Glasgow, Neal A.; Cheyne, Michele; Yerrick, Randy K.

    2010-01-01

    The experience and science expertise of these award-winning authors makes this easy-to-use guide a teacher's treasure trove. This latest edition to the popular What Successful Teachers Do series describes 75 research-based strategies and outlines best practices for inquiry-oriented science. Each strategy includes a brief description of the…

  11. An adaptive demodulation approach for bearing fault detection based on adaptive wavelet filtering and spectral subtraction

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Tang, Baoping; Liu, Ziran; Chen, Rengxiang

    2016-02-01

    Fault diagnosis of rolling element bearings is important for improving mechanical system reliability and performance. Vibration signals contain a wealth of complex information useful for state monitoring and fault diagnosis. However, any fault-related impulses in the original signal are often severely tainted by various noises and the interfering vibrations caused by other machine elements. Narrow-band amplitude demodulation has been an effective technique to detect bearing faults by identifying bearing fault characteristic frequencies. To achieve this, the key step is to remove the corrupting noise and interference, and to enhance the weak signatures of the bearing fault. In this paper, a new method based on adaptive wavelet filtering and spectral subtraction is proposed for fault diagnosis in bearings. First, to eliminate the frequency associated with interfering vibrations, the vibration signal is bandpass filtered with a Morlet wavelet filter whose parameters (i.e. center frequency and bandwidth) are selected in separate steps. An alternative and efficient method of determining the center frequency is proposed that utilizes the statistical information contained in the production functions (PFs). The bandwidth parameter is optimized using a local ‘greedy’ scheme along with Shannon wavelet entropy criterion. Then, to further reduce the residual in-band noise in the filtered signal, a spectral subtraction procedure is elaborated after wavelet filtering. Instead of resorting to a reference signal as in the majority of papers in the literature, the new method estimates the power spectral density of the in-band noise from the associated PF. The effectiveness of the proposed method is validated using simulated data, test rig data, and vibration data recorded from the transmission system of a helicopter. The experimental results and comparisons with other methods indicate that the proposed method is an effective approach to detecting the fault-related impulses

  12. Adaption strategies to the effect of climate change on a coastal area in Northwest Germany with different land management scenarios

    NASA Astrophysics Data System (ADS)

    Graeff, Thomas; Krause, Stefan; Maier, Martin; Oswald, Sascha

    2015-04-01

    Coastal areas are highly vulnerable to the impact of climate change and handling is difficult. Adaption to two different situations has to be taken into account. On the one hand, increasing global sea level in combination with increased precipitation and higher storm surge frequency has to be handled. On the other hand, in summer periods due to the increase of temperature, enhanced evapotranspiration and an increase of salty seawater intrusion into groundwater have to be managed. In this study we present different landuse management scenarios on a coastal area in Northwest Germany, East Frisia, and their effect on the hydrological response. Landuse is dominated by dairy farming and intensive crop farming. 30 percent of the area lies below sea level. A dense channel network in combination with several pumping stations allows permeant drainage. The soils are characterised by marsh soils and impermeable layers which prevent an interaction with the confined brackish aquifer. Observations in those areas indicate a high salinity with concentrations peaking during the summer period. The landuse strategies include a scenario that the technological level of the management will be adapted to rainfall and sea level but without additional drainage from the hinterland to reduce salt water concentration. A second scenario includes the adaptation to increasing precipitation and the sea level with a polder system and wetland areas designated as potential buffer for winter storm surges and inland floods and as freshwater storage for dry summer periods. Two scenarios use large polder areas in the future as potential buffer for winter storm surges and inland floods and as freshwater storage for dry summer periods, additional usage for nature conservation and as the storage of carbon sequestration or extensive farming are planned. Also, stakeholders have developed a system of several smaller polders in combination with an intensification of the water resource management, and this is

  13. Integrating adaptive behaviour in large-scale flood risk assessments: an Agent-Based Modelling approach

    NASA Astrophysics Data System (ADS)

    Haer, Toon; Aerts, Jeroen

    2015-04-01

    Between 1998 and 2009, Europe suffered over 213 major damaging floods, causing 1126 deaths, displacing around half a million people. In this period, floods caused at least 52 billion euro in insured economic losses making floods the most costly natural hazard faced in Europe. In many low-lying areas, the main strategy to cope with floods is to reduce the risk of the hazard through flood defence structures, like dikes and levees. However, it is suggested that part of the responsibility for flood protection needs to shift to households and businesses in areas at risk, and that governments and insurers can effectively stimulate the implementation of individual protective measures. However, adaptive behaviour towards flood risk reduction and the interaction between the government, insurers, and individuals has hardly been studied in large-scale flood risk assessments. In this study, an European Agent-Based Model is developed including agent representatives for the administrative stakeholders of European Member states, insurers and reinsurers markets, and individuals following complex behaviour models. The Agent-Based Modelling approach allows for an in-depth analysis of the interaction between heterogeneous autonomous agents and the resulting (non-)adaptive behaviour. Existing flood damage models are part of the European Agent-Based Model to allow for a dynamic response of both the agents and the environment to changing flood risk and protective efforts. By following an Agent-Based Modelling approach this study is a first contribution to overcome the limitations of traditional large-scale flood risk models in which the influence of individual adaptive behaviour towards flood risk reduction is often lacking.

  14. Comparing Anisotropic Output-Based Grid Adaptation Methods by Decomposition

    NASA Technical Reports Server (NTRS)

    Park, Michael A.; Loseille, Adrien; Krakos, Joshua A.; Michal, Todd

    2015-01-01

    Anisotropic grid adaptation is examined by decomposing the steps of flow solution, ad- joint solution, error estimation, metric construction, and simplex grid adaptation. Multiple implementations of each of these steps are evaluated by comparison to each other and expected analytic results when available. For example, grids are adapted to analytic metric fields and grid measures are computed to illustrate the properties of multiple independent implementations of grid adaptation mechanics. Different implementations of each step in the adaptation process can be evaluated in a system where the other components of the adaptive cycle are fixed. Detailed examination of these properties allows comparison of different methods to identify the current state of the art and where further development should be targeted.

  15. AMGET, an R-Based Postprocessing Tool for ADAPT 5

    PubMed Central

    Guiastrennec, B; Wollenberg, L; Forrest, A; Ait-Oudhia, S

    2013-01-01

    ADAPT 5 is a powerful modeling software for population pharmacokinetic and pharmacodynamic systems analysis, but provides limited built-in functionality for creating pre- and post-analysis diagnostic plots. ADAPT 5 Model Evaluation Graphical Toolkit (AMGET), an external package written in the open source R programming language, was developed specifically to support efficient postprocessing of ADAPT 5 runs, as well as NONMEM and S-ADAPT runs. Using interactive navigational menus, users of AMGET are able to rapidly create informative diagnostic plots enriched by the display of numerical and graphical elements with a high degree of customization using a simple settings spreadsheet. This article describes each feature of the AMGET package and illustrates how it allows users to utilize the powerful numerical routines of the ADAPT 5 package in a more efficient manner through the use of a simulated dataset and a simple pharmacokinetic model optimized using the maximum likelihood expectation maximization (MLEM) algorithm of ADAPT 5. PMID:23903464

  16. Simple adaptive sparse representation based classification schemes for EEG based brain-computer interface applications.

    PubMed

    Shin, Younghak; Lee, Seungchan; Ahn, Minkyu; Cho, Hohyun; Jun, Sung Chan; Lee, Heung-No

    2015-11-01

    One of the main problems related to electroencephalogram (EEG) based brain-computer interface (BCI) systems is the non-stationarity of the underlying EEG signals. This results in the deterioration of the classification performance during experimental sessions. Therefore, adaptive classification techniques are required for EEG based BCI applications. In this paper, we propose simple adaptive sparse representation based classification (SRC) schemes. Supervised and unsupervised dictionary update techniques for new test data and a dictionary modification method by using the incoherence measure of the training data are investigated. The proposed methods are very simple and additional computation for the re-training of the classifier is not needed. The proposed adaptive SRC schemes are evaluated using two BCI experimental datasets. The proposed methods are assessed by comparing classification results with the conventional SRC and other adaptive classification methods. On the basis of the results, we find that the proposed adaptive schemes show relatively improved classification accuracy as compared to conventional methods without requiring additional computation.

  17. Design of a Virtual Reality Based Adaptive Response Technology for Children With Autism

    PubMed Central

    Lahiri, Uttama; Bekele, Esubalew; Dohrmann, Elizabeth; Warren, Zachary; Sarkar, Nilanjan

    2013-01-01

    Children with autism spectrum disorder (ASD) demonstrate potent impairments in social communication skills including atypical viewing patterns during social interactions. Recently, several assistive technologies, particularly virtual reality (VR), have been investigated to address specific social deficits in this population. Some studies have coupled eye-gaze monitoring mechanisms to design intervention strategies. However, presently available systems are designed to primarily chain learning via aspects of one’s performance only which affords restricted range of individualization. The presented work seeks to bridge this gap by developing a novel VR-based interactive system with Gaze-sensitive adaptive response technology that can seamlessly integrate VR-based tasks with eye-tracking techniques to intelligently facilitate engagement in tasks relevant to advancing social communication skills. Specifically, such a system is capable of objectively identifying and quantifying one’s engagement level by measuring real-time viewing patterns, subtle changes in eye physiological responses, as well as performance metrics in order to adaptively respond in an individualized manner to foster improved social communication skills among the participants. The developed system was tested through a usability study with eight adolescents with ASD. The results indicate the potential of the system to promote improved social task performance along with socially-appropriate mechanisms during VR-based social conversation tasks. PMID:23033333

  18. Design of a virtual reality based adaptive response technology for children with autism.

    PubMed

    Lahiri, Uttama; Bekele, Esubalew; Dohrmann, Elizabeth; Warren, Zachary; Sarkar, Nilanjan

    2013-01-01

    Children with autism spectrum disorder (ASD) demonstrate potent impairments in social communication skills including atypical viewing patterns during social interactions. Recently, several assistive technologies, particularly virtual reality (VR), have been investigated to address specific social deficits in this population. Some studies have coupled eye-gaze monitoring mechanisms to design intervention strategies. However, presently available systems are designed to primarily chain learning via aspects of one's performance only which affords restricted range of individualization. The