WorldWideScience

Sample records for scale control

  1. Normalization of emotion control scale

    Directory of Open Access Journals (Sweden)

    Hojatoolah Tahmasebian

    2014-09-01

    Full Text Available Background: Emotion control skill teaches the individuals how to identify their emotions and how to express and control them in various situations. The aim of this study was to normalize and measure the internal and external validity and reliability of emotion control test. Methods: This standardization study was carried out on a statistical society, including all pupils, students, teachers, nurses and university professors in Kermanshah in 2012, using Williams’ emotion control scale. The subjects included 1,500 (810 females and 690 males people who were selected by stratified random sampling. Williams (1997 emotion control scale, was used to collect the required data. Emotional Control Scale is a tool for measuring the degree of control people have over their emotions. This scale has four subscales, including anger, depressed mood, anxiety and positive affect. The collected data were analyzed by SPSS software using correlation and Cronbach's alpha tests. Results: The results of internal consistency of the questionnaire reported by Cronbach's alpha indicated an acceptable internal consistency for emotional control scale, and the correlation between the subscales of the test and between the items of the questionnaire was significant at 0.01 confidence level. Conclusion: The validity of emotion control scale among the pupils, students, teachers, nurses and teachers in Iran has an acceptable range, and the test itemswere correlated with each other, thereby making them appropriate for measuring emotion control.

  2. Impedance Scaling and Impedance Control

    Energy Technology Data Exchange (ETDEWEB)

    Chou, W.; Griffin, J.

    1997-06-01

    When a machine becomes really large, such as the Very Large Hadron Collider (VLHC), of which the circumference could reach the order of megameters, beam instability could be an essential bottleneck. This paper studies the scaling of the instability threshold vs. machine size when the coupling impedance scales in a ``normal`` way. It is shown that the beam would be intrinsically unstable for the VLHC. As a possible solution to this problem, it is proposed to introduce local impedance inserts for controlling the machine impedance. In the longitudinal plane, this could be done by using a heavily detuned rf cavity (e.g., a biconical structure), which could provide large imaginary impedance with the right sign (i.e., inductive or capacitive) while keeping the real part small. In the transverse direction, a carefully designed variation of the cross section of a beam pipe could generate negative impedance that would partially compensate the transverse impedance in one plane.

  3. Scale and corrosion control with combined dolomite/calcite filter.

    Science.gov (United States)

    Log, T; Simpson, G; Hanssen, H K; Robinson, M; Hubble, J; Parsons, S A

    2004-01-01

    Water quality is a major operational issue for boiler operation and control. If the water is hard scale control is required and if it is soft then corrosion control is an issue. Here a two stream boiler test rig has been used to test the effect a fixed bed filter has on the scaling and corrosion properties of both hard and soft waters. The filter effectively controlled the pH, hardness and alkalinity of both waters leading to significant decreases in scale formation and effective control of corrosion.

  4. Large-scale cryopumping for controlled fusion

    Energy Technology Data Exchange (ETDEWEB)

    Pittenger, L.C.

    1977-07-25

    Vacuum pumping by freezing out or otherwise immobilizing the pumped gas is an old concept. In several plasma physics experiments for controlled fusion research, cryopumping has been used to provide clean, ultrahigh vacua. Present day fusion research devices, which rely almost universally upon neutral beams for heating, are high gas throughput systems, the pumping of which is best accomplished by cryopumping in the high mass-flow, moderate-to-high vacuum regime. Cryopumping systems have been developed for neutral beam injection systems on several fusion experiments (HVTS, TFTR) and are being developed for the overall pumping of a large, high-throughput mirror containment experiment (MFTF). In operation, these large cryopumps will require periodic defrosting, some schemes for which are discussed, along with other operational considerations. The development of cryopumps for fusion reactors is begun with the TFTR and MFTF systems. Likely paths for necessary further development for power-producing reactors are also discussed.

  5. Scale Transformations and Information Presentation in Supervisory Control

    DEFF Research Database (Denmark)

    Petersen, Johannes; May, Michael

    2006-01-01

    It is commonly accepted that designers of supervisory control systems cannot comprehensively anticipate operators' information needs. In order to compensate the lack between the information presented by the Supervisory control system and the information needed, operators tailor the information...... presentation. Currently, there is a lack of theoretical understanding of tailoring activities and hence fundamental principles for the design of Supervisory control systems that support tailoring activities in a systematic manner. Any data being presented to the operator is oil one of the four different scale...... types proposed by Stevens. The scale type of data is determined by how values are assigned to the dimensions of the system being supervised and each scale type specifies a set of operations that can be legitimately applied to data oil this scale type. Based on the concept of scale transformation...

  6. Energy scaling and reduction in controlling complex networks

    Science.gov (United States)

    Chen, Yu-Zhong; Wang, Le-Zhi; Wang, Wen-Xu; Lai, Ying-Cheng

    2016-01-01

    Recent works revealed that the energy required to control a complex network depends on the number of driving signals and the energy distribution follows an algebraic scaling law. If one implements control using a small number of drivers, e.g. as determined by the structural controllability theory, there is a high probability that the energy will diverge. We develop a physical theory to explain the scaling behaviour through identification of the fundamental structural elements, the longest control chains (LCCs), that dominate the control energy. Based on the LCCs, we articulate a strategy to drastically reduce the control energy (e.g. in a large number of real-world networks). Owing to their structural nature, the LCCs may shed light on energy issues associated with control of nonlinear dynamical networks. PMID:27152220

  7. Scaling up Intermittent Rice Irrigation for Malaria Control on the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Scaling up Intermittent Rice Irrigation for Malaria Control on the North Coast of Peru. New research aims to help control malaria in one watershed in northern Peru. Malaria is widespread in Peru's arid North Coast because of the extensive irrigation required to support rice paddies. Rice growing in the region accounts for ...

  8. Closed loop high precision position control system with optical scale

    Science.gov (United States)

    Ge, Cheng-liang; Liao, Yuan; He, Zhong-wu; Luo, Zhong-xiang; Huang, Zhi-wei; Wan, Min; Hu, Xiao-yang; Fan, Guo-bin; Liang, Zheng

    2008-03-01

    With the developments of science of art, there are more and more demands on the high resolution control of position of object to be controlled, such as lathe, product line, elements in the optical resonant cavity, telescope, and so on. As one device with high resolution, the optical scale has more and more utility within the industrial and civil applications. With one optical scale and small DC servo motor, one closed loop high resolution position control system is constructed. This apparatus is used to control the position of the elements of optical system. The optical scale is attached on the object or reference guide way. The object position is sampled by a readhead of non-contact optical encoder. Control system processes the position information and control the position of object through the motion control of servo DC motor. The DC motor is controlled by one controller which is connected to an industrial computer. And the micro frictionless slide table does support the smooth motion of object to be controlled. The control algorithm of system is PID (Proportional-Integral-Differential) methods. The PID control methods have well ROBUST. The needed data to control are position, velocity and acceleration of the object. These three parameters correspond to the PID characters respectively. After the accomplishments of hardware, GUI (Graphical user interface), that is, the software of control system is also programmed. The whole system is assembled by specialized worker. Through calibration experiments, the coefficients of PID are obtained respectively. And then the precision of position control of the system is about 0.1μm.

  9. Performance evaluation on reactor power control by H{sup {infinity}} controller with gain scaling

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Nobuyuki; Suzuki, Katsuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-05-01

    A `gain scaling method` is proposed to improve the performance of reactor power control by the controller based on linear control theory. The method is derived from the simple nonlinearity of the neutron kinetics of reactor that is caused by the cross term of input reactivity and neutronic output. It is the main idea to scale down the control input generated by the linear controller with respect to the reactor power level. The evaluation of the performance of H{sup {infinity}} control system with the gain scaling in time and frequency domains indicates the effectiveness of the proposed method. (author)

  10. Model Predictive Control for a Small Scale Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Jianfu Du

    2008-11-01

    Full Text Available Kinematical and dynamical equations of a small scale unmanned helicoper are presented in the paper. Based on these equations a model predictive control (MPC method is proposed for controlling the helicopter. This novel method allows the direct accounting for the existing time delays which are used to model the dynamics of actuators and aerodynamics of the main rotor. Also the limits of the actuators are taken into the considerations during the controller design. The proposed control algorithm was verified in real flight experiments where good perfomance was shown in postion control mode.

  11. Development and Validation of the Eating Loss of Control Scale

    OpenAIRE

    Blomquist, Kerstin K.; Roberto, Christina A.; Barnes, Rachel D.; White, Marney A.; Masheb, Robin M.; Grilo, Carlos M.

    2013-01-01

    Recurrent objective bulimic episodes (OBE) are a defining diagnostic characteristic of binge eating disorder (BED) and bulimia nervosa (BN). OBEs are characterized by experiencing loss of control (LOC) while eating an unusually large quantity of food. Despite nosological importance and complex heterogeneity across patients, measurement of LOC has been assessed dichotomously (present/absent). This study describes the development and initial validation of the Eating Loss of Control Scale (ELOCS...

  12. The EWMA control chart based on robust scale estimators

    OpenAIRE

    Nadia Saeed; Shahid Kamal

    2016-01-01

    The exponentially weighted moving average (EWMA) chart is very popular in statistical process control for detecting the small shifts in process mean and variance. This chart performs well under the assumption of normality but when data violate the assumption of normality, the robust approaches needed. We have developed the EWMA charts under different robust scale estimators available in literature and also compared the performance of these charts by calculating expected out-of-control points ...

  13. Large-scale stabilization control of input-constrained quadrotor

    Directory of Open Access Journals (Sweden)

    Jun Jiang

    2016-10-01

    Full Text Available The quadrotor has been the most popular aircraft in the last decade due to its excellent dynamics and continues to attract ever-increasing research interest. Delivering a quadrotor from a large fixed-wing aircraft is a promising application of quadrotors. In such an application, the quadrotor needs to switch from a highly unstable status, featured as large initial states, to a safe and stable flight status. This is the so-called large-scale stability control problem. In such an extreme scenario, the quadrotor is at risk of actuator saturation. This can cause the controller to update incorrectly and lead the quadrotor to spiral and crash. In this article, to safely control the quadrotor in such scenarios, the control input constraint is analyzed. The key states of a quadrotor dynamic model are selected, and a two-dimensional dynamic model is extracted based on a symmetrical body configuration. A generalized point-wise min-norm nonlinear control method is proposed based on the Lyapunov function, and large-scale stability control is hence achieved. An enhanced point-wise, min-norm control is further provided to improve the attitude control performance, with altitude performance degenerating slightly. Simulation results showed that the proposed control methods can stabilize the input-constrained quadrotor and the enhanced method can improve the performance of the quadrotor in critical states.

  14. Large-scale disasters: prediction, control, and mitigation

    National Research Council Canada - National Science Library

    Gad-El-Hak, M

    2008-01-01

    ... an integrated review of the broad research field of large-scale disasters. It establishes a common framework for predicting, controlling, and managing both manmade and natural disasters. There is a particular focus on events caused by weather and climate change. Other topics include air pollution, tsunamis, disaster modeling, the use of re...

  15. Conservation biological control and enemy diversity on a landscape scale

    NARCIS (Netherlands)

    Tscharntke, T.; Bommarco, R.; Clough, Y.; Crist, T.O.; Kleijn, D.; Rand, T.A.; Tylianakis, J.M.; Nouhuys, S.; Vidal, S.

    2007-01-01

    Conservation biological control in agroecosystems requires a landscape management perspective, because most arthropod species experience their habitat at spatial scales beyond the plot level, and there is spillover of natural enemies across the crop–noncrop interface. The species pool in the

  16. Developing a Scale on the Usage of Learner Control Strategy

    Science.gov (United States)

    Kutlu, M. Oguz

    2012-01-01

    The aim of this study was to develop a Likert-like scale in order to measure teachers' usage level of learner control strategy. This study was carried out with 219 State primary school teachers who were class teachers, Turkish teachers, English teachers, Mathematics teachers, Science teachers, Social Sciences teachers, Religion and Moral teachers…

  17. Reproducible and controllable induction voltage adder for scaled beam experiments

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko [Department of Energy Sciences, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

    2016-08-15

    A reproducible and controllable induction adder was developed using solid-state switching devices and Finemet cores for scaled beam compression experiments. A gate controlled MOSFET circuit was developed for the controllable voltage driver. The MOSFET circuit drove the induction adder at low magnetization levels of the cores which enabled us to form reproducible modulation voltages with jitter less than 0.3 ns. Preliminary beam compression experiments indicated that the induction adder can improve the reproducibility of modulation voltages and advance the beam physics experiments.

  18. Calcium carbonate scale control in once-through cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J.M.; McDowell, J.F. (Betz Lab., Inc., The Woodlands, TX (US)); Heflin, R.F. (Betz Industrial, Bismark, ND (US)); Karlovich, D.N. (Beltz Industrial, Trevosa, PA (US)); Bloom, M.F. (Minnkota Power Cooperative, Inc., Grand Forks, ND (USA))

    1989-01-01

    This paper reports on a laboratory-scale model surface condenser used to design a successful once-through cooling water treatment program for calcium carbonate scale inhibition at Young Station. The treatment program has maintained the station's condenser cleanliness factor at approximately 100% for the duration of the treatment. The model surface condensers simulate cycled systems as well as once-through cooling systems. They are fully automated with computer-controlled chemical feed, flow, heat flux, makeup, and blowdown and data acquisition systems.

  19. Controlled flight of a biologically inspired, insect-scale robot.

    Science.gov (United States)

    Ma, Kevin Y; Chirarattananon, Pakpong; Fuller, Sawyer B; Wood, Robert J

    2013-05-03

    Flies are among the most agile flying creatures on Earth. To mimic this aerial prowess in a similarly sized robot requires tiny, high-efficiency mechanical components that pose miniaturization challenges governed by force-scaling laws, suggesting unconventional solutions for propulsion, actuation, and manufacturing. To this end, we developed high-power-density piezoelectric flight muscles and a manufacturing methodology capable of rapidly prototyping articulated, flexure-based sub-millimeter mechanisms. We built an 80-milligram, insect-scale, flapping-wing robot modeled loosely on the morphology of flies. Using a modular approach to flight control that relies on limited information about the robot's dynamics, we demonstrated tethered but unconstrained stable hovering and basic controlled flight maneuvers. The result validates a sufficient suite of innovations for achieving artificial, insect-like flight.

  20. Formation control for a network of small-scale robots.

    Science.gov (United States)

    Kim, Yoonsoo

    2014-10-01

    In this paper, a network of small-scale robots (typically centimeter-scale robots) equipped with artificial actuators such as electric motors is considered. The purpose of this network is to have the robots keep a certain formation shape (or change to another formation shape) during maneuvers. The network has a fixed communication topology in the sense that robots have a fixed group of neighbors to communicate during maneuvers. Assuming that each robot and its actuator can be modeled as a linear system, a decentralized control law (such that each robot activates its actuator based on the information from its neighbors only) is introduced to achieve the purpose of formation keeping or change. A linear matrix inequality (LMI) for deriving the upper bound on the actuator's time constant is also presented. Simulation results are shown to demonstrate the merit of the introduced control law.

  1. The EWMA control chart based on robust scale estimators

    Directory of Open Access Journals (Sweden)

    Nadia Saeed

    2016-12-01

    Full Text Available The exponentially weighted moving average (EWMA chart is very popular in statistical process control for detecting the small shifts in process mean and variance. This chart performs well under the assumption of normality but when data violate the assumption of normality, the robust approaches needed. We have developed the EWMA charts under different robust scale estimators available in literature and also compared the performance of these charts by calculating expected out-of-control points and expected widths under non-symmetric distributions (i.e. gamma and exponential. The simulation studies are being carried out for the purpose and results showed that amongst six robust estimators, the chart based on estimator Q_n relatively performed well for non-normal processes in terms of its shorter expected width and more number of expected out-of-control points which shows its sensitivity to detect the out of control signal.

  2. Development and validation of the eating loss of control scale.

    Science.gov (United States)

    Blomquist, Kerstin K; Roberto, Christina A; Barnes, Rachel D; White, Marney A; Masheb, Robin M; Grilo, Carlos M

    2014-03-01

    Recurrent objective bulimic episodes (OBE) are a defining diagnostic characteristic of binge eating disorder (BED) and bulimia nervosa (BN). OBEs are characterized by experiencing loss of control (LOC) while eating an unusually large quantity of food. Despite nosological importance and complex heterogeneity across patients, measurement of LOC has been assessed dichotomously (present/absent). This study describes the development and initial validation of the Eating Loss of Control Scale (ELOCS), a self-report questionnaire that examines the complexity of the LOC construct. Participants were 168 obese treatment-seeking individuals with BED who completed the Eating Disorder Examination interview and self-report measures. Participants rated their LOC-related feelings or behaviors on continuous Likert-type scales and reported the number of LOC episodes in the past 28 days. Principal component analysis identified a single-factor, 18-item scale, which demonstrated good internal reliability (α = .90). Frequency of LOC episodes was significantly correlated with frequency of OBEs and subjective bulimic episodes. The ELOCS demonstrated good convergent validity and was significantly correlated with greater eating pathology, greater emotion dysregulation, greater depression, and lower self-control but not with body mass index. The findings suggest that the ELOCS is a valid self-report questionnaire that may provide important clinical information regarding experiences of LOC in obese persons with BED. Future research should examine the ELOCS in other eating disorders and nonclinical samples. 2014 APA

  3. Self-Control Scale AS-36: Construction and validation study

    Directory of Open Access Journals (Sweden)

    Nęcka Edward

    2015-09-01

    Full Text Available This paper presents a validation study of a new questionnaire of self-control as an individual trait. The questionnaire has two parallel versions, one based on self-reports (AS-36 and another one based on informant reports (AS-36-3. Each version consists of three subscales, called Inhibition (12 items, Switching (12 items, and Goal Monitoring (12 items. Eight samples of participants (N = 935 altogether took part in the validation study. Both versions obtained satisfactory indices of internal consistency, assessed with Cronbach’s alpha and split-half coefficients. Selfcontrol assessed with this scale proved to be entirely independent of general intelligence. However, AS-36 and AS-36-3 scores tended to correlate with other self-report measures of trait self control, such as Tangney, Baumeister, and Boone’s (2004 self-control scale. We conclude that AS-36 is a valid and reliable tool, suitable for assessment of self-control in both research and diagnostic settings.

  4. Identification of safety controls for engineering-scale pyroprocess facility

    Directory of Open Access Journals (Sweden)

    Seong-In Moon

    2015-12-01

    Full Text Available Pyroprocess technology has been considered as a fuel cycle option to solve the spent fuel accumulation problems in Korea. The Korea Atomic Energy Research Institute, Daejeon, Korea has been studying pyroprocess technology, and the conceptual design of an engineering-scale pyroprocess facility, called the Reference Engineering-scale Pyroprocess Facility, has been performed on the basis of a 10 ton heavy metal throughput per year. In this paper the concept of Reference Engineering-scale Pyroprocess Facility is introduced along with its safety requirements for the protection of facility workers, collocated workers, the off-site public, and the environment. For the identification of safety structures, systems, and components and/or administrative controls, the following activities were conducted: (1 identifying hazards associated with operations; (2 identifying potential events associated with these hazards; and (3 identifying the potential preventive and/or mitigative controls that reduce the risk associated with these accident events. This study will be used to perform a safety evaluation for accidents involving any of the hazards identified, and to establish safety design policies and propose a more definite safety design.

  5. Supervisory control of a pilot-scale cooling loop

    Energy Technology Data Exchange (ETDEWEB)

    Kris Villez; Venkat Venkatasubramanian; Humberto Garcia

    2011-08-01

    We combine a previously developed strategy for Fault Detection and Identification (FDI) with a supervisory controller in closed loop. The combined method is applied to a model of a pilot-scale cooling loop of a nuclear plant, which includes Kalman filters and a model-based predictive controller as part of normal operation. The system has two valves available for flow control meaning that some redundancy is available. The FDI method is based on likelihood ratios for different fault scenarios which in turn are derived from the application of the Kalman filter. A previously introduced extension of the FDI method is used here to enable detection and identification of non-linear faults like stuck valve problems and proper accounting of the time of fault introduction. The supervisory control system is designed so to take different kinds of actions depending on the status of the fault diagnosis task and on the type of identified fault once diagnosis is complete. Some faults, like sensor bias and drift, are parametric in nature and can be adjusted without need for reconfiguration of the regulatory control system. Other faults, like a stuck valve problem, require reconfiguration of the regulatory control system. The whole strategy is demonstrated for several scenarios.

  6. Experimental control of scaling behavior: what is not fractal?

    Science.gov (United States)

    Likens, Aaron D; Fine, Justin M; Amazeen, Eric L; Amazeen, Polemnia G

    2015-10-01

    The list of psychological processes thought to exhibit fractal behavior is growing. Although some might argue that the seeming ubiquity of fractal patterns illustrates their significance, unchecked growth of that list jeopardizes their relevance. It is important to identify when a single behavior is and is not fractal in order to make meaningful conclusions about the processes underlying those patterns. The hypothesis tested in the present experiment is that fractal patterns reflect the enactment of control. Participants performed two steering tasks: steering on a straight track and steering on a circular track. Although each task could be accomplished by holding the steering wheel at a constant angle, steering around a curve may require more constant control, at least from a psychological standpoint. Results showed that evidence for fractal behavior was strongest for the circular track; straight tracks showed evidence of two scaling regions. We argue from those results that, going forward, the goal of the fractal literature should be to bring scaling behavior under experimental control.

  7. The construction of a normative scale of locus of control

    Directory of Open Access Journals (Sweden)

    Johann M. Schepers

    2005-10-01

    Full Text Available The primary objective of the study was to construct a normative scale of locus of control for use with students and adults. A corollary of the study was to establish the personality, interest and cognitive correlates of locus of control. Conceptually the instrument is based on attribution theory and on social learning theory. The first edition of the Locus of Control Inventory (LCI was applied to 356 first-year university students during 1994. A factor analysis of the 65 items of the inventory yielded three factors. The factors were interpreted as Autonomy, Internal Control and External Control. Three scales, corresponding to the three factors, were constructed, and yielded reliability coefficients of 0,80; 0,77 and 0,81 respectively. Following this the cognitive, interest and personality correlates of the LCI were determined. The implications of the findings are discussed. Opsomming Die hoofdoel van die studie was die konstruksie van ’n normatiewe skaal van lokus van beheer vir gebruik met studente en volwassenes. ’n Newe-doelwit van die studie was om die persoonlikheids-, belangstellings- en kognitiewe korrelate van lokus van beheer te bepaal. Konseptueel is die instrument op attribusieteorie en sosiale-leerteorie gebaseer. Die eerste-uitgawe van die Lokus van Beheervraelys (LvB is op 356 eerstejaaruniversiteitstudente toegepas gedurende 1994. ’n Faktorontleding van die 65 items van die vraelys is gedoen en het drie faktore opgelewer. Die faktore is as Outonomie, Interne Beheer en Eksterne Beheer geïnterpreteer. Voorts is drie skale wat ooreenstem met die drie faktore, gekonstrueer en het betroubaarhede van 0,80; 0,77 en 0,81, onderskeidelik, opgelewer. Vervolgens is die kognitiewe, belangstellings- en persoonlikheidskorrelate van die LvB bepaal. Die implikasies van die bevindinge word bespreek.

  8. Dynamic Modeling, Optimization, and Advanced Control for Large Scale Biorefineries

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail

    plant [3]. The goal of the project is to utilize realtime data extracted from the large scale facility to formulate and validate first principle dynamic models of the plant. These models are then further exploited to derive model-based tools for process optimization, advanced control and real...... with building a plantwide model-based optimization layer, which searches for optimal values regarding the pretreatment temperature, enzyme dosage in liquefaction, and yeast seed in fermentation such that profit is maximized [7]. When biomass is pretreated, by-products are also created that affect the downstream...

  9. Synchronization control for large-scale network systems

    CERN Document Server

    Wu, Yuanqing; Su, Hongye; Shi, Peng; Wu, Zheng-Guang

    2017-01-01

    This book provides recent advances in analysis and synthesis of Large-scale network systems (LSNSs) with sampled-data communication and non-identical nodes. In its first chapter of the book presents an introduction to Synchronization of LSNSs and Algebraic Graph Theory as well as an overview of recent developments of LSNSs with sampled data control or output regulation control. The main text of the book is organized into two main parts - Part I: LSNSs with sampled-data communication and Part II: LSNSs with non-identical nodes. This monograph provides up-to-date advances and some recent developments in the analysis and synthesis issues for LSNSs with sampled-data communication and non-identical nodes. It describes the constructions of the adaptive reference generators in the first stage and the robust regulators in the second stage. Examples are presented to show the effectiveness of the proposed design techniques.

  10. Design and Control of Full Scale Wave Energy Simulator System

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Hansen, Anders Hedegaard; Hansen, Rico Hjerm

    2012-01-01

    For wave energy to become feasible it is a requirement that the efficiency and reliability of the power take-off (PTO) systems are significantly improved. The cost of installing and testing PTO-systems at sea are however very high, and the focus of the current paper is therefore on the design...... of a full scale wave simulator for testing PTO-systems for point absorbers. The main challenge is here to design a system, which mimics the behavior of a wave when interacting with a given PTO-system. The paper includes a description of the developed system, located at Aalborg University......, and the considerations behind the design. Based on the description a model of the system is presented, which, along with a description of the wave theory applied, makes the foundation for the control strategy. The objective of the control strategy is to emulate not only the wave behavior, but also the dynamic wave...

  11. [Validation of a sport injury locus of control scale].

    Science.gov (United States)

    Paquet, Y

    2008-04-01

    In the area of health psychology, locus of control (LOC) [Psychol Monogr 80 (1966) 1-28] has consistently been considered as a dimension of personality which may entail many potential benefits for the individual. Originally, the LOC by Rotter [Psychol Monogr 80 (1966) 1-28] is a unidimensional concept. He defines: on one hand individuals with an internal LOC who establish a link between their behavior and the reinforcement obtained, and on the other hand, individuals with an external LOC who do not establish any link between their behavior and the reinforcement obtained. However, since Rotter, other authors like Levenson [Distinctions within the concept of internal-external control: development of a new scale. In: Proceedings of the 80th annual convention of the American psychological association. 1972. p. 261-2] have claimed a multidimensional concept with three factors: the internal (I), powerful other (P), and chance (C). The MHLCS was constructed with three factors, according to Levenson's model. Numerous scales have been designed in order to assess health-related LOC. The most widely used is the MHLCS [Health Educ Monogr 6 (1978) 160-170]. According to Lecocq [La réhabilitation après la blessure. In: Manuel de psychologie du sport : l'intervention auprès du sportif. Paris: Revue EPS; 2003. p. 377-402], such a multidimensional view would allow in-depth examinations of sport injuries. Indeed, from a theoretical perspective, sport participants with high LOC ratings are assumed to suffer less frequent injuries than those scoring low on this dimension. The purpose of the present paper is to present an adapted version of the MHLCS in French language. For Bruchon-Schweitzer [Bruchon-Schweitzer M, Dantzer R. Introduction à la psychologie de la santé. Paris: Presses universitaires de France; 1994], the three factors (I, P, and C) are independent or a little intercorrelated. Therefore, two models of sport injury LOC scale have been studied: the first with three

  12. Large-scale climatic control on European precipitation

    Science.gov (United States)

    Lavers, David; Prudhomme, Christel; Hannah, David

    2010-05-01

    Atlantic air. The Balkans' precipitation shows a linkage with the Siberian High pressure system. With the onset of spring and summer the correlation patterns shift in location and the winter correlation dipole breaks down. In summer, fewer significant correlations between the MSLP (large-scale climate) and precipitation are found across Europe. This results in smaller scale correlation patterns and possibly suggests that warm-season precipitation is predominantly generated by local or regional scale convective systems. These convective systems are not likely to be captured by large-scale atmospheric patterns of MSLP. In conclusion this research shows: 1) the detailed change in large-scale climatic control on precipitation across Europe, and 2) the geographic regions with strongest correlation between precipitation and MSLP shift from month-to-month, highlighting the dynamic nature of precipitation generating weather systems throughout the year. This study also shows that the utility of an in-situ index to describe precipitation occurrence, such as the NAO, is likely to be limited because the seasonal movements of the large-scale climate patterns are not captured.

  13. Hydrologic controls on basin-scale distribution of benthic invertebrates

    Science.gov (United States)

    Ceola, Serena; Bertuzzo, Enrico; Singer, Gabriel; Battin, Tom J.; Montanari, Alberto; Rinaldo, Andrea

    2014-04-01

    Streamflow variability is a major determinant of basin-scale distributions of benthic invertebrates. Here we present a novel procedure based on a probabilistic approach aiming at a spatially explicit quantitative assessment of benthic invertebrate abundance as derived from near-bed flow variability. Although the proposed approach neglects ecological determinants other than hydraulic ones, it is nevertheless relevant in view of its implications on the predictability of basin-scale patterns of organisms. In the present context, aquatic invertebrates are considered, given that they are widely employed as sensitive indicators of fluvial ecosystem health and human-induced perturbations. Moving from the analytical characterization of site-specific probability distribution functions of streamflow and bottom shear stress, we achieve a spatial extension to an entire stream network. Bottom shear stress distributions, coupled with habitat suitability curves derived from field studies, are used to produce maps of invertebrate suitability to shear stress conditions. Therefore, the proposed framework allows one to inspect the possible impacts on river ecology of human-induced perturbations of streamflow variability. We apply this framework to an Austrian river network for which rainfall and streamflow time series, river network hydraulic properties, and local information on invertebrate abundance for a limited number of sites are available. A comparison between observed species density versus modeled suitability to shear stress is also presented. Although the proposed strategy focuses on a single controlling factor and thus represents an ecological minimal model, it allows derivation of important implications for water resource management and fluvial ecosystem protection.

  14. Electrodialytic remediation of air pollution control residues in bench scale

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Ferreira, Celia; Hansen, Henrik K.

    2008-01-01

    Air pollution control (APC) residue from municipal solid waste incineration (MSWI) is considered a hazardous waste due to its alkalinity and high content of salts and mobile heavy metals. Various solutions for the handling of APC-residue exist in different regions; however, most commercial....... A system resembling conventional electrodialysis was designed and adjusted to fit the high solids content feed solution (10% APC residue, 90% water). Experiments were made in bench scale with raw residue (natural pH > 12), water pre-residue (natural pH > 12), acid pre-washed residue (pH 10), and acid......-treated residue (pH 2). Our results show that the soluble fraction of the toxic elements Pb, Cu, Cd and Zn was removed from the feed solution and concentrated in the concentrate solution. Furthermore, the leaching (leaching test at L/S 2) of these elements was substantially reduced during treatment (fig. 1...

  15. Does a Growing Static Length Scale Control the Glass Transition?

    Science.gov (United States)

    Wyart, Matthieu; Cates, Michael E.

    2017-11-01

    Several theories of the glass transition propose that the structural relaxation time τα is controlled by a growing static length scale ξ that is determined by the free energy landscape but not by the local dynamic rules governing its exploration. We argue, based on recent simulations using particle-radius-swap dynamics, that only a modest factor in the increase in τα on approach to the glass transition may stem from the growth of a static length, with a vastly larger contribution attributable, instead, to a slowdown of local dynamics. This reinforces arguments that we base on the observed strong coupling of particle diffusion and density fluctuations in real glasses.

  16. Fine scale spatial variability of microbial pesticide degradation in soil: scales, controlling factors, and implications

    DEFF Research Database (Denmark)

    Dechesne, Arnaud; Badawi, N.; Aamand, Jens

    2014-01-01

    Pesticide biodegradation is a soil microbial function of critical importance for modern agriculture and its environmental impact. While it was once assumed that this activity was homogeneously distributed at the field scale, mounting evidence indicates that this is rarely the case. Here, we...... critically examine the literature on spatial variability of pesticide biodegradation in agricultural soil. We discuss the motivations, methods, and main findings of the primary literature. We found significant diversity in the approaches used to describe and quantify spatial heterogeneity, which complicates...... across pesticide classes: they include some soil characteristics (pH) and some agricultural management practices (pesticide application, tillage), while other potential controlling factors have more conflicting effects depending on the site or the pesticide. Evidence demonstrating the importance...

  17. Pilot-scale cooling tower to evaluate corrosion, scaling, and biofouling control strategies for cooling system makeup water.

    Science.gov (United States)

    Chien, S H; Hsieh, M K; Li, H; Monnell, J; Dzombak, D; Vidic, R

    2012-02-01

    Pilot-scale cooling towers can be used to evaluate corrosion, scaling, and biofouling control strategies when using particular cooling system makeup water and particular operating conditions. To study the potential for using a number of different impaired waters as makeup water, a pilot-scale system capable of generating 27,000 kJ∕h heat load and maintaining recirculating water flow with a Reynolds number of 1.92 × 10(4) was designed to study these critical processes under conditions that are similar to full-scale systems. The pilot-scale cooling tower was equipped with an automatic makeup water control system, automatic blowdown control system, semi-automatic biocide feeding system, and corrosion, scaling, and biofouling monitoring systems. Observed operational data revealed that the major operating parameters, including temperature change (6.6 °C), cycles of concentration (N = 4.6), water flow velocity (0.66 m∕s), and air mass velocity (3660 kg∕h m(2)), were controlled quite well for an extended period of time (up to 2 months). Overall, the performance of the pilot-scale cooling towers using treated municipal wastewater was shown to be suitable to study critical processes (corrosion, scaling, biofouling) and evaluate cooling water management strategies for makeup waters of complex quality.

  18. Mesoscopic length scale controls the rheology of dense suspensions.

    Science.gov (United States)

    Bonnoit, Claire; Lanuza, Jose; Lindner, Anke; Clement, Eric

    2010-09-03

    From the flow properties of dense granular suspensions on an inclined plane, we identify a mesoscopic length scale strongly increasing with volume fraction. When the flowing layer height is larger than this length scale, a diverging Newtonian viscosity is determined. However, when the flowing layer height drops below this scale, we evidence a nonlocal effective viscosity, decreasing as a power law of the flow height. We establish a scaling relation between this mesoscopic length scale and the suspension viscosity. These results support recent theoretical and numerical results implying collective and clustered granular motion when the jamming point is approached from below.

  19. Modelling of vegetative filter strips in catchment scale erosion control

    Directory of Open Access Journals (Sweden)

    K. RANKINEN

    2008-12-01

    Full Text Available The efficiency of vegetative filter strips to reduce erosion was assessed by simulation modelling in two catchments located in different parts of Finland. The areas of high erosion risk were identified by a Geographical Information System (GIS combining digital spatial data of soil type, land use and field slopes. The efficiency of vegetative filter strips (VFS was assessed by the ICECREAM model, a derivative of the CREAMS model which has been modified and adapted for Finnish conditions. The simulation runs were performed without the filter strips and with strips of 1 m, 3 m and 15 m width. Four soil types and two crops (spring barley, winter wheat were studied. The model assessments for fields without VFS showed that the amount of erosion is clearly dominated by slope gradient. The soil texture had a greater impact on erosion than the crop. The impact of the VFS on erosion reduction was highly variable. These model results were scaled up by combining them to the digital spatial data. The simulated efficiency of the VFS in erosion control in the whole catchment varied from 50 to 89%. A GIS-based erosion risk map of the other study catchment and an identification carried out by manual study using topographical paper maps were evaluated and validated by ground truthing. Both methods were able to identify major erosion risk areas, i.e areas where VFS are particularly necessary. A combination of the GIS and the field method gives the best outcome.

  20. Fine scale spatial variability of microbial pesticide degradation in soil: scales, controlling factors, and implications

    Science.gov (United States)

    Dechesne, Arnaud; Badawi, Nora; Aamand, Jens; Smets, Barth F.

    2014-01-01

    Pesticide biodegradation is a soil microbial function of critical importance for modern agriculture and its environmental impact. While it was once assumed that this activity was homogeneously distributed at the field scale, mounting evidence indicates that this is rarely the case. Here, we critically examine the literature on spatial variability of pesticide biodegradation in agricultural soil. We discuss the motivations, methods, and main findings of the primary literature. We found significant diversity in the approaches used to describe and quantify spatial heterogeneity, which complicates inter-studies comparisons. However, it is clear that the presence and activity of pesticide degraders is often highly spatially variable with coefficients of variation often exceeding 50% and frequently displays non-random spatial patterns. A few controlling factors have tentatively been identified across pesticide classes: they include some soil characteristics (pH) and some agricultural management practices (pesticide application, tillage), while other potential controlling factors have more conflicting effects depending on the site or the pesticide. Evidence demonstrating the importance of spatial heterogeneity on the fate of pesticides in soil has been difficult to obtain but modeling and experimental systems that do not include soil's full complexity reveal that this heterogeneity must be considered to improve prediction of pesticide biodegradation rates or of leaching risks. Overall, studying the spatial heterogeneity of pesticide biodegradation is a relatively new field at the interface of agronomy, microbial ecology, and geosciences and a wealth of novel data is being collected from these different disciplinary perspectives. We make suggestions on possible avenues to take full advantage of these investigations for a better understanding and prediction of the fate of pesticides in soil. PMID:25538691

  1. Fine scale spatial variability of microbial pesticide degradation in soil: scales, controlling factors, and implications

    Directory of Open Access Journals (Sweden)

    Arnaud eDechesne

    2014-12-01

    Full Text Available Pesticide biodegradation is a soil microbial function of critical importance for modern agriculture and its environmental impact. While it was once assumed that this activity was homogeneously distributed at the field scale, mounting evidence indicates that this is rarely the case. Here, we critically examine the literature on spatial variability of pesticide biodegradation in agricultural soil. We discuss the motivations, methods, and main findings of the primary literature. We found significant diversity in the approaches used to describe and quantify spatial heterogeneity, which complicates inter-studies comparisons. However, it is clear that the presence and activity of pesticide degraders is often highly spatially variable with coefficients of variation often exceeding 50% and frequently displays nonrandom spatial patterns. A few controlling factors have tentatively been identified across pesticide classes: they include some soil characteristics (pH and some agricultural management practices (pesticide application, tillage, while other potential controlling factors have more conflicting effects depending on the site or the pesticide. Evidence demonstrating the importance of spatial heterogeneity on the fate of pesticides in soil has been difficult to obtain but modelling and experimental systems that do not include soil’s full complexity reveal that this heterogeneity must be considered to improve prediction of pesticide biodegradation rates or of leaching risks. Overall, studying the spatial heterogeneity of pesticide biodegradation is a relatively new field at the interface of agronomy, microbial ecology, and geosciences and a wealth of novel data is being collected from these different disciplinary perspectives. We make suggestions on possible avenues to take full advantage of these investigations for a better understanding and prediction of the fate of pesticides in soil.

  2. Genetic and Environmental Influences on Self-Control : Assessing Self-Control with the ASEBA Self-Control Scale

    NARCIS (Netherlands)

    Willems, Yayouk E; Dolan, Conor V; van Beijsterveldt, Catharina E M; de Zeeuw, E.L.; Boomsma, Dorret I; Bartels, Meike; Finkenauer, Catrin

    2018-01-01

    This study used a theoretically-derived set of items of the Achenbach System of Empirically Based Assessment to develop the Achenbach Self-Control Scale (ASCS) for 7-16 year olds. Using a large dataset of over 20,000 children, who are enrolled in the Netherlands Twin Register, we demonstrated the

  3. Organization of nosocomial infection control measures and local networks for infectious disease control in middle-scale hospitals in Japan.

    Science.gov (United States)

    Mori-Yoshikawa, Namiko; Ohmagari, Norio; Kirikae, Teruo

    2014-01-01

    The aims of this study were to assess nosocomial infection control measures at middle-scale hospitals throughout Japan. Of the 823 hospitals participating in this questionnaire-based survey, more than half of the middle-scale hospitals have implemented nosocomial infection control measures, including infection surveillance or infection control rounds, while acknowledging a shortage of infection control staff. These hospitals most frequently consulted public health centers to obtain information and advice. Improved nosocomial infection control in middle-scale hospitals requires sufficient staffing and a local network, with active participation by public health centers.

  4. Efficient model predictive control for large-scale urban traffic networks

    NARCIS (Netherlands)

    Lin, S.

    2011-01-01

    Model Predictive Control is applied to control and coordinate large-scale urban traffic networks. However, due to the large scale or the nonlinear, non-convex nature of the on-line optimization problems solved, the MPC controllers become real-time infeasible in practice, even though the problem is

  5. GEOMORPHOLOGY. Experimental evidence for hillslope control of landscape scale.

    Science.gov (United States)

    Sweeney, K E; Roering, J J; Ellis, C

    2015-07-03

    Landscape evolution theory suggests that climate sets the scale of landscape dissection by modulating the competition between diffusive processes that sculpt convex hillslopes and advective processes that carve concave valleys. However, the link between the relative dominance of hillslope and valley transport processes and landscape scale is difficult to demonstrate in natural landscapes due to the episodic nature of erosion. Here, we report results from laboratory experiments combining diffusive and advective processes in an eroding landscape. We demonstrate that rainsplash-driven disturbances in our experiments are a robust proxy for hillslope transport, such that increasing hillslope transport efficiency decreases drainage density. Our experimental results demonstrate how the coupling of climate-driven hillslope- and valley-forming processes, such as bioturbation and runoff, dictates the scale of eroding landscapes. Copyright © 2015, American Association for the Advancement of Science.

  6. Method and apparatus for actively controlling a micro-scale flexural plate wave device

    Science.gov (United States)

    Dohner, Jeffrey L.

    2001-01-01

    An actively controlled flexural plate wave device provides a micro-scale pump. A method of actively controlling a flexural plate wave device produces traveling waves in the device by coordinating the interaction of a magnetic field with actively controlled currents. An actively-controlled flexural plate wave device can be placed in a fluid channel and adapted for use as a micro-scale fluid pump to cool or drive micro-scale systems, for example, micro-chips, micro-electrical-mechanical devices, micro-fluid circuits, or micro-scale chemical analysis devices.

  7. Improved control of a small-scale biomass boiler

    Energy Technology Data Exchange (ETDEWEB)

    Sulc, B.; Klimanek, D. [Czech Technical Univ., Prague (Czech Republic). Dept. of Fluid Dynamics and Power Engineering; Hrdlicka, J. [Czech Technical Univ., Prague (Czech Republic). Dept. of Fluid Dynamics and Power Engineering

    2007-07-01

    It is often difficult to detect errors in combustion chamber sensors. Sub-optimal combustion can lead to increased emissions of air pollutants and greenhouse gases (GHGs). Air flow must be controlled in order to reduce gaseous emissions and maintain steady fuel combustion rates. Oxygen sensor discredibility occurs when sensor properties have shifted to provide biased data. Gradual changes in the sensor can occur over time, causing oxygen control loops to react to incorrect information about the fuel-air ratio by attempting to remove unreal control errors. This paper described a control system designed to reduce emissions from an experimental biomass boiler equipped with an oxygen sensor. A valve and controller was used to control air flow for optimal combustion. The sensor discredibility detection method was based on a model of a control variable sensor modified to inform operators of changes when sensor parameters exceeded the limits of the tolerance range. The control system extended the function of standard controllers and detected imprecision in control loop operations while providing normal control functions. The design will be used to reduce the environmental footprint of larger biomass systems. 14 refs., 3 tabs., 3 figs.

  8. Small-Scale Helicopter Automatic Autorotation : Modeling, Guidance, and Control

    NARCIS (Netherlands)

    Taamallah, S.

    2015-01-01

    Our research objective consists in developing a, model-based, automatic safety recovery system, for a small-scale helicopter Unmanned Aerial Vehicle (UAV) in autorotation, i.e. an engine OFF flight condition, that safely flies and lands the helicopter to a pre-specified ground location. In pursuit

  9. Escala de Locus de controle ELCO/TELEBRÁS Scale of Locus of control - ELCO

    Directory of Open Access Journals (Sweden)

    Luiz Pasquali

    1998-01-01

    Full Text Available Com base na teoria de Rotter e Escala de Levenson foi elaborada uma escala de Locus de Controle Organizacional (ELCO, composta por 28 itens. A escala foi validada com uma amostra de 350 empregados do Sistema Telebrás. Verificou-se a presença dos 2 fatores previstos na teoria, a saber: internalidade e externalidade, aparecendo a escala de externalidade, com 18 itens, bem estruturada (alfa = 0.81 e a de internalidade, com 10 itens, deixando a desejar no que se refere à consistência interna (alfa = 0.66. Com os dados desta pesquisa foi feita também análise do Locus de Controle desses mesmos empregados. A constatação mais saliente foi a de que o nível de internalidade caiu com o aumento do nível escolar e o aumento da experiência profissional desses mesmos empregados. Estes resultados surpreendentes foram interpretados em termos da situação típica da empresa, que está passando por um período de transição, a saber: a passagem da condição de empresa estatal para empresa privada, o que seria motivo da perda de confiança dos empregados na própria competência, particularmente por parte daqueles com maior competência intelectual e maior experiência profissional. Fez-se igualmente reparos na qualidade psicométrica da escala e da própria teoria do Locus de controle, no sentido de que esta precisa ser melhor axiomatizada para possibilitar a elaboração de escalas mais precisas para a medida dos construtos que propõe.A scale with 28 items, the Organizational Locus of Control (ELCO, was built based on Rotter’s theory and Levenson’s scale. ELCO was validated on a sample of 350 employees of Telebrás, a governmental firm in Brazil. As foreseen from the theory, a principal-axis factoring showed the presence of the expected two factors, namely internal and external locus of control. The external locus of control factor, composed of 18 items, showed good internal consistency (alpha =.81 whereas the internal factor, with 10 items

  10. A large scale mastitis control programme in Somerset.

    Science.gov (United States)

    Brander, G C; Watkins, J H; Gard, R P

    1975-10-18

    The results of a mastitis control programme operated in south west England for three years are given. Farmers participating in the full mastitis control group agreed to treat each cow at drying off with 500 mg benzathine cloxacillin in each quarter, to have their milking machines tested and to correct any faults, and to practise teat dipping. Data covering cell counts, milk production, milk quality and clinical mastitis, were assessed from herds taking part in the programme. Cell counts were analysed from all 507 herds taking part in the programme. Milk production records for the full mastitis control group (188 herds) over a three year period are discussed, and these results compared with milk production figures from Milk Marketing Board records from herds in the south west of England which were carrying out no specific mastitis control programme. The milk quality data compare the findings in 159 herds in the full mastitis control programme with those in 247 herds in the partial and no mastitis control groups. Cases of clinical mastitis during the three year period were recorded in 73 herds in the full mastitis control group. The problems of applying the control routines are presented with observations on clinical mastitis, bulk milk cell count, milk production and milk quality. After three years, herds in the programme had on average increased milk production by 75 gallons a cow, achieved a 14.6 per cent reduction in the incidence of clinical mastitis, and improved the milk total solids percentage by one milk quality payment class.

  11. Physical control oriented model of large scale refrigerators to synthesize advanced control schemes. Design, validation, and first control results

    Science.gov (United States)

    Bonne, François; Alamir, Mazen; Bonnay, Patrick

    2014-01-01

    In this paper, a physical method to obtain control-oriented dynamical models of large scale cryogenic refrigerators is proposed, in order to synthesize model-based advanced control schemes. These schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in the cryogenic cooling systems of future fusion reactors such as the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT-60SA). Advanced control schemes lead to a better perturbation immunity and rejection, to offer a safer utilization of cryoplants. The paper gives details on how basic components used in the field of large scale helium refrigeration (especially those present on the 400W @1.8K helium test facility at CEA-Grenoble) are modeled and assembled to obtain the complete dynamic description of controllable subsystems of the refrigerator (controllable subsystems are namely the Joule-Thompson Cycle, the Brayton Cycle, the Liquid Nitrogen Precooling Unit and the Warm Compression Station). The complete 400W @1.8K (in the 400W @4.4K configuration) helium test facility model is then validated against experimental data and the optimal control of both the Joule-Thompson valve and the turbine valve is proposed, to stabilize the plant under highly variable thermals loads. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  12. Durable Feedback Control System for Small Scale Wood Chip Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Korpela, T.; Bjoerkqvist, T.; Lautala, P. (Tampere Univ. of Technology, Dept. of Automation Science and Engineering, FIN-33101 Tampere (Finland)). E-mail: timo.korpela@tut.fi

    2008-10-15

    The purpose is to control wood chip combustion in an inexpensive and durable way. A control concept in order to reduce the effect of fluctuation of the fuel feed is introduced. The concept is based on temperature and lambda measurements. The main task of the control system is to set the fuel feed at a desired level after a change in the combustion conditions. Additionally, temporary fluctuations of the degree of filling of feeding screw are compensated. Test results of a 80 kW and a 200 kW commercial wood chip fired systems are introduced. The process experiments indicate that the high level control system is able to adapt to varying combustion conditions and to maintain low emission levels. Furthermore, passive means that can be exploited to stabilize the combustion are discussed. As the control concept is not dependent on the design of the combustion system, the concept is adaptable to present systems

  13. Fine scale spatial variability of microbial pesticide degradation in soil: scales, controlling factors, and implications

    OpenAIRE

    Arnaud eDechesne; Nora eBadawi; Jens eAamand; Smets, Barth F.

    2014-01-01

    Pesticide biodegradation is a soil microbial function of critical importance for modern agriculture and its environmental impact. While it was once assumed that this activity was homogeneously distributed at the field scale, mounting evidence indicates that this is rarely the case. Here, we critically examine the literature on spatial variability of pesticide biodegradation in agricultural soil. We discuss the motivations, methods, and main findings of the primary literature. We found signifi...

  14. Automated large-scale control of gene regulatory networks.

    Science.gov (United States)

    Tan, Mehmet; Alhajj, Reda; Polat, Faruk

    2010-04-01

    Controlling gene regulatory networks (GRNs) is an important and hard problem. As it is the case in all control problems, the curse of dimensionality is the main issue in real applications. It is possible that hundreds of genes may regulate one biological activity in an organism; this implies a huge state space, even in the case of Boolean models. This is also evident in the literature that shows that only models of small portions of the genome could be used in control applications. In this paper, we empower our framework for controlling GRNs by eliminating the need for expert knowledge to specify some crucial threshold that is necessary for producing effective results. Our framework is characterized by applying the factored Markov decision problem (FMDP) method to the control problem of GRNs. The FMDP is a suitable framework for large state spaces as it represents the probability distribution of state transitions using compact models so that more space and time efficient algorithms could be devised for solving control problems. We successfully mapped the GRN control problem to an FMDP and propose a model reduction algorithm that helps find approximate solutions for large networks by using existing FMDP solvers. The test results reported in this paper demonstrate the efficiency and effectiveness of the proposed approach.

  15. Estimation and Control with Relative Measurements: Algorithms and Scaling Laws

    Science.gov (United States)

    2007-09-01

    AIAA-2002-4491. [20] R. G. Bill and W. F. Herrnkind. Drag reduction by formation movement in spiny lobsters. Science, vol. 193, no. 4258: 1146–1148...133] G. Lafferriere, A. Williams , J. S. Caughman and J. J. P. Veerman. Decen- tralized control of vehicle formations. Systems & Control Letters, vol. 54...Chaos, Solitons, and Fractals , vol. 11: 1621–1660, 2000. [166] A. J. Rivas-Guerra and M. P. Mignolet. Local/global effects of mistuning on the

  16. Stability and Control of Large-Scale Dynamical Systems A Vector Dissipative Systems Approach

    CERN Document Server

    Haddad, Wassim M

    2011-01-01

    Modern complex large-scale dynamical systems exist in virtually every aspect of science and engineering, and are associated with a wide variety of physical, technological, environmental, and social phenomena, including aerospace, power, communications, and network systems, to name just a few. This book develops a general stability analysis and control design framework for nonlinear large-scale interconnected dynamical systems, and presents the most complete treatment on vector Lyapunov function methods, vector dissipativity theory, and decentralized control architectures. Large-scale dynami

  17. Karolinska Scales of Personality, cognition and psychotic symptoms in patients with schizophrenia and healthy controls.

    Science.gov (United States)

    Nilsson, Björn Mikael; Holm, Gunnar; Ekselius, Lisa

    2016-01-01

    Studies on both personality dimensions and cognition in schizophrenia are scarce. The objective of the present study was to examine personality traits and the relation to cognitive function and psychotic symptoms in a sample of patients with schizophrenia and healthy controls. In total 23 patients with schizophrenia and 14 controls were assessed with the Karolinska Scales of Personality (KSP). A broad cognitive test programme was used, including the Wechsler Adult Intelligence Scales, the Finger-Tapping Test, the Trail Making Test, the Verbal Fluency Test, the Benton Visual Retention Test, the Wisconsin Card Sorting Test and Rey Auditory Verbal Learning Test . Compared with controls, the patients exhibited prominent elevations on KSP scales measuring anxiety proneness and neuroticism (P = 0.000005-0.0001), on the Detachment scale (P Aggression, Suspicion, Guilt and Irritability scales (P = 0.002-0.03) while the remaining five scales did not differ between patients and controls. KSP anxiety-related scales correlated with the Positive and Negative Symptoms Scale (PANSS) general psychopathology subscale. Cognitive test results were uniformly lower in the patient group and correlated with PANSS negative symptoms subscale. There was no association between KSP scale scores and PANSS positive or negative symptoms. The patients revealed a highly discriminative KSP test profile with elevated scores in neuroticism- and psychoticism-related scales as compared to controls. Results support previous findings utilizing other personality inventories in patients with schizophrenia. Cognitive test performance correlated inversely with negative symptoms.

  18. Facilitating dynamo action via control of large-scale turbulence.

    Science.gov (United States)

    Limone, A; Hatch, D R; Forest, C B; Jenko, F

    2012-12-01

    The magnetohydrodynamic dynamo effect is considered to be the major cause of magnetic field generation in geo- and astrophysical systems. Recent experimental and numerical results show that turbulence constitutes an obstacle to dynamos; yet its role in this context is not totally clear. Via numerical simulations, we identify large-scale turbulent vortices with a detrimental effect on the amplification of the magnetic field in a geometry of experimental interest and propose a strategy for facilitating the dynamo instability by manipulating these detrimental "hidden" dynamics.

  19. Controlling benthic release of phosphorus in different Baltic Sea scales

    DEFF Research Database (Denmark)

    Pitkänen, Heikki; Bendtsen, Jørgen; Hansen, Jørgen L. S.

    The general aim of the PROPPEN project was to study whether it is possible to counteract near-bottom anoxia and excess benthic nutrient release ("internal loading") in the Baltic Sea by artificial oxygenation in cost-efficient and socio-economically beneficial ways. Two pilot sites were selected...... to counteract anoxia and benthic release of nutrients in coastal marine conditions in the Baltic Sea. The project undertook monitoring of the pilot tests, modelling of effects at different scales, risk management, cost effectiveness and cost benefit analysis....

  20. Localized field control at the nano-scale

    Science.gov (United States)

    Fujiwara, Hideki; Yasuda, Yuki; Orita, Hiroaki; Ishida, Shutaro; Sasaki, Keiji

    2017-04-01

    We investigate the wavelength dependence of localized plasmonic field distributions in a gold nanodimer structure under total internal reflection condition. Although a gold dimer structure is well known to induce strong localized mode at a nanogap, we find that the higher-order plasmonic modes are excited by the oblique light incidence and their interference effect enables us to observe the modification of localized filed distributions at the nano-scale even in a simple gold nanodimer structure depending on the detection wavelength. This change in the plasmonic field distribution would provide important knowledge for their potential applications such as plasmonic trapping, spectroscopy, and sensing.

  1. Atomic-Scale Control of Electron Transport through Single Molecules

    DEFF Research Database (Denmark)

    Wang, Y. F.; Kroger, J.; Berndt, R.

    2010-01-01

    Tin-phthalocyanine molecules adsorbed on Ag(111) were contacted with the tip of a cryogenic scanning tunneling microscope. Orders-of-magnitude variations of the single-molecule junction conductance were achieved by controllably dehydrogenating the molecule and by modifying the atomic structure...

  2. Quality Control Charts in Large-Scale Assessment Programs

    Science.gov (United States)

    Schafer, William D.; Coverdale, Bradley J.; Luxenberg, Harlan; Jin, Ying

    2011-01-01

    There are relatively few examples of quantitative approaches to quality control in educational assessment and accountability contexts. Among the several techniques that are used in other fields, Shewart charts have been found in a few instances to be applicable in educational settings. This paper describes Shewart charts and gives examples of how…

  3. Multidimensional health locus of control scales: applicability among ...

    African Journals Online (AJOL)

    Exploratory factor analysis gave two sub-factors of the MHLC corresponding to internal and provider control over health and having internal consistency reliability of 0.72 and 0.76, respectively. Conclusion: The results lend support to the cultural correspondence of the MHLC instrument, several aspects of its validity and ...

  4. Optimally Scaled H(sub infinity) Full Information Control Synthesis with Real Uncertainty

    Science.gov (United States)

    Balas, Gary J.; Lind, Rick; Packard, Andy

    1996-01-01

    This paper presents an algorithm to synthesize optimal controllers for the scaled H(sub infinity). full information problem with real and complex uncertainty. The control problem is reduced to a linear matrix inequality which can be solved via a finite dimensional convex optimization. This technique is compared with the optimal scaled H(sub infinity). full information with only complex uncertainty and D - K iteration control design to synthesize controllers for a missile autopilot. Directly including real parametric uncertainty into the control design results in improved robust performance of the missile autopilot. The controller synthesized via D - K iteration achieves results similar to the optimal designs.

  5. A Local Controller for Discrete-Time Large-Scale System by Using Integral Variable Structure Control

    Directory of Open Access Journals (Sweden)

    C. H. Chai

    2015-01-01

    Full Text Available A new local controller for discrete-time integral variable structure control of a large-scale system with matched and unmatched uncertainty is presented. The local controller is able to bring the large-scale system into stability by using only the states feedback from individual subsystem itself. A new theorem is established and proved that the controller is able to handle the effect of interconnection for the large-scale system with matched and unmatched uncertainty, and the system stability is ensured. The controller is able to control the system to achieve the quasi-sliding surface and remains on it. The results showed a fast convergence to the desired value and the attenuation of disturbance is achieved.

  6. Controlling time scales for electron transfer through proteins

    Directory of Open Access Journals (Sweden)

    Scot Wherland

    2015-12-01

    Full Text Available Electron transfer processes within proteins constitute key elements in biological energy conversion processes as well as in a wide variety of biochemical transformations. Pursuit of the parameters that control the rates of these processes is driven by the great interest in the latter reactions. Here, we review a considerable body of results emerging from investigation of intramolecular electron transfer (ET reactions in two types of proteins, all done by the use of the pulse-radiolysis method: first are described results of extensive studies of a model system, the bacterial electron mediating protein azurin, where an internal ET between the disulfide radical ion and the Cu(II is induced. Impact of specific structural changes introduced into azurin on the reaction rates and the parameters controlling it are discussed. Then, the presentation is extended to results of investigations of intra-protein ET reactions that are part of catalytic cycles of multi-copper containing enzymes. Again, the rates and the parameters controlling them are presented and discussed in the context of their efficacy and possible constraints set on their evolution.

  7. Issue in pollution control: interplant cost differences and economies of scale.

    Science.gov (United States)

    Pittman, R.W.

    1981-01-01

    Seeks evidence concerning the issues of the relative efficiencies of different institutional arrangements for pollution control and the implications of control requirements for economies of scale and barriers to entry. Data is derived from the estimation of a production function for 30 pulp and paper mills in Wisconsin and Michigan. Concludes that the systematic differences in marginal treatment costs for different mills are evidence of serious inefficiencies resulting from the current (US) system of pollution control regulation. The positive association of pollution control intensity with economies of scale suggests that any pollution control regime has some negative allocational effects in this industry (and presumably others). -K.Turner

  8. Minimum scale controlled topology optimization and experimental test of a micro thermal actuator

    DEFF Research Database (Denmark)

    Heo, S.; Yoon, Gil Ho; Kim, Y.Y.

    2008-01-01

    This paper is concerned with the optimal topology design, fabrication and test of a micro thermal actuator. Because the minimum scale was controlled during the design optimization process, the production yield rate of the actuator was improved considerably; alternatively, the optimization design...... without scale control resulted in a very low yield rate. Using the minimum scale controlling topology design method developed earlier by the authors, micro thermal actuators were designed and fabricated through a MEMS process. Moreover, both their performance and production yield were experimentally...

  9. Decentralised stabilising controllers for a class of large-scale linear ...

    Indian Academy of Sciences (India)

    A simple method for computing decentralised stabilising controllers for a class of large-scale (interconnected) linear systems has been developed. Decentralised controls are optimal controls at subsystem level and are generated from the solution of algebraic Riccati equations for decoupled subsystems resulting from a new ...

  10. The Research of PID Control in a Large Scale Helium Refrigerator

    Science.gov (United States)

    Pan, W.; Wu, J. H.; Li, L. F.; Liu, H. M.; Li, Q.

    2015-12-01

    In the development of a helium refrigerator, the control of load temperature stability is an important requirement. We usually use multistage control strategies to achieve the precise control of it. Each level has its strict control logic. PID controllers are the core control module in the process. Therefore, a research of its principle and parameters’ setting occupies an important position in the development work. This paper detailed describes the PID control principle used in a large scale helium refrigerator of 10kW@20K, as well as several improvements on PID parameters’ setting, by using simulations and experiments in combination. The temperature is eventually controlled more precise.

  11. Evidence of factorial validity of parental knowledge, control and solicitation, and adolescent disclosure scales : When the ordered nature of Likert scales matters

    NARCIS (Netherlands)

    Lionetti, Francesca; Keijsers, L.G.M.T.; Dellagiulia, Antonio; Pastore, Massimiliano

    2016-01-01

    For evaluating monitoring and parent-adolescent communication, a set of scales addressing parental knowledge, control and solicitation, and adolescent disclosure was proposed by Kerr and Stattin (2000). Although these scales have been widely disseminated, their psychometric proprieties have often

  12. Multiple-Time-Scales Hierarchical Frequency Stability Control Strategy of Medium-Voltage Isolated Microgrid

    DEFF Research Database (Denmark)

    Zhao, Zhuoli; Yang, Ping; Guerrero, Josep M.

    2016-01-01

    In this paper, an islanded medium-voltage (MV) microgrid placed in Dongao Island is presented, which integrates renewable-energy-based distributed generations (DGs), energy storage system (ESS), and local loads. In an isolated microgrid without connection to the main grid to support the frequency......, it is more complex to control and manage. Thus in order to maintain the frequency stability in multiple-time-scales, a hierarchical control strategy is proposed. The proposed control architecture divides the system frequency in three zones: (A) stable zone, (B) precautionary zone and (C) emergency zone....... In this way, dynamic stability control that cope with disturbances in short-time scale is implemented by microgrid central controller (MGCC) within Zone B and Zone C. Meanwhile, steady-state stability control to solve the peaks and valleys problem of loads and DGs in long-time scale is executed by microgrid...

  13. Vartiational Optimal-Control Problems with Delayed Arguments on Time Scales

    Directory of Open Access Journals (Sweden)

    Abdeljawad (Maraaba Thabet

    2009-01-01

    Full Text Available This paper deals with variational optimal-control problems on time scales in the presence of delay in the state variables. The problem is considered on a time scale unifying the discrete, the continuous, and the quantum cases. Two examples in the discrete and quantum cases are analyzed to illustrate our results.

  14. Substrate controls on the longitudinal profile of bedrock channels: Implications for reach-scale roughness

    Science.gov (United States)

    Jaime R. Goode; Ellen Wohl

    2010-01-01

    In this paper we examine the relationships among bedrock properties and hydraulics in shaping bedrock channel morphology at the reach scale. The Ocoee River and four other bedrock streams in the Blue Ridge province of the southeastern United States, which have reach scale differences in bedrock erodibility controlled by lithologic and structural variation, are the...

  15. Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller

    NARCIS (Netherlands)

    Soons, Z.I.T.A.; IJssel, van den J.; Pol, van der L.A.; Straten, van G.; Boxtel, van A.J.B.

    2009-01-01

    Abstract This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation

  16. A Limited Evaluation of Full Scale Control Surface Deflection Drag (Have FUN)

    National Research Council Canada - National Science Library

    Reinhardt, R. B; Celi, Sean A; Geraghty, Jeffrey T; Stahl, James W; Glover, Victor J; Bowman, Geoffrey G

    2007-01-01

    The Have FUN (FUll Scale Numbers) Test Management Project was conducted at the request of the USAF TPS as an investigation into the drag caused by control surface deflection during dynamic soaring techniques...

  17. Zero-order Approximation of Three-time Scale Singular Linear-quadratic Optimal Control Problem

    National Research Council Canada - National Science Library

    Kalashnikova, M. A

    2015-01-01

    This paper is devoted to the construction of a zero-order approximation of the solution of a three-time scale singular perturbed linear-quadratic optimal control problem with the help of the direct scheme method...

  18. Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller.

    Science.gov (United States)

    Soons, Zita I T A; van den IJssel, Jan; van der Pol, Leo A; van Straten, Gerrit; van Boxtel, Anton J B

    2009-04-01

    This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation of the oxygen uptake rate, the starting point for online monitoring and control of biomass growth, taking into account the dynamics in the gas-phase. Mixing effects and delays are caused by amongst others the headspace and tubing to the analyzer. These gas phase dynamics are modelled using knowledge of the system in order to reconstruct oxygen consumption. The second aspect is to evaluate performance of the monitoring and control system with the required modifications of the oxygen consumption calculation on pilot-scale. In pilot-scale fed-batch cultivation good monitoring and control performance is obtained enabling a doubled concentration of bulk vaccine compared to standard batch production.

  19. Preventing large-scale controlled substance diversion from within the pharmacy.

    Science.gov (United States)

    Martin, Emory S; Dzierba, Steven H; Jones, David M

    2013-05-01

    Large-scale diversion of controlled substances (CS) from within a hospital or heath system pharmacy is a rare but growing problem. It is the responsibility of pharmacy leadership to scrutinize control processes to expose weaknesses. This article reviews examples of large-scale diversion incidents and diversion techniques and provides practical strategies to stimulate enhanced CS security within the pharmacy staff. Large-scale diversion from within a pharmacy department can be averted by a pharmacist-in-charge who is informed and proactive in taking effective countermeasures.

  20. [Reliability and validity of the Japanese translation of Brief Self-Control Scale (BSCS-J)].

    Science.gov (United States)

    Ozaki, Yuka; Goto, Takayuki; Kobayashi, Mai; Kutsuzawa, Gaku

    2016-06-01

    Self-control refers to the ability to execute goal-oriented behavior despite the presence of temptation(s) to do otherwise. Since self-control has a wide-range impact on our daily lives, it is of critical importance to assess individual differences of self-control with a highly reliable and valid, yet simple, measure. Toward this end, three studies were conducted to test reliability and validity of the Japanese-translated version of Brief Self-Control Scale (Tangney, Baumeister, & Boone, 2004). The scale showed good internal consistency (Study 1) and retest reliability (Study 2). The. total score of the scale was correlated with the self-reported indices of self-control (e.g., daily experience of ego-depletion, study hours) and performance in the Stop Signal Task (Study 3), indicating its high converging validity.

  1. Macro-mechanics controls quantum mechanics: mechanically controllable quantum conductance switching of an electrochemically fabricated atomic-scale point contact

    Science.gov (United States)

    Staiger, Torben; Wertz, Florian; Xie, Fangqing; Heinze, Marcel; Schmieder, Philipp; Lutzweiler, Christian; Schimmel, Thomas

    2018-01-01

    Here, we present a silver atomic-scale device fabricated and operated by a combined technique of electrochemical control (EC) and mechanically controllable break junction (MCBJ). With this EC-MCBJ technique, we can perform mechanically controllable bistable quantum conductance switching of a silver quantum point contact (QPC) in an electrochemical environment at room temperature. Furthermore, the silver QPC of the device can be controlled both mechanically and electrochemically, and the operating mode can be changed from ‘electrochemical’ to ‘mechanical’, which expands the operating mode for controlling QPCs. These experimental results offer the perspective that a silver QPC may be used as a contact for a nanoelectromechanical relay.

  2. Macro-mechanics controls quantum mechanics: mechanically controllable quantum conductance switching of an electrochemically fabricated atomic-scale point contact.

    Science.gov (United States)

    Staiger, Torben; Wertz, Florian; Xie, Fangqing; Heinze, Marcel; Schmieder, Philipp; Lutzweiler, Christian; Schimmel, Thomas

    2018-01-12

    Here, we present a silver atomic-scale device fabricated and operated by a combined technique of electrochemical control (EC) and mechanically controllable break junction (MCBJ). With this EC-MCBJ technique, we can perform mechanically controllable bistable quantum conductance switching of a silver quantum point contact (QPC) in an electrochemical environment at room temperature. Furthermore, the silver QPC of the device can be controlled both mechanically and electrochemically, and the operating mode can be changed from 'electrochemical' to 'mechanical', which expands the operating mode for controlling QPCs. These experimental results offer the perspective that a silver QPC may be used as a contact for a nanoelectromechanical relay.

  3. A single gene (yes controls pigmentation of eyes and scales in Heliothis virescens

    Directory of Open Access Journals (Sweden)

    Thomas M. Brown

    2001-02-01

    Full Text Available A yellow-eyed mutant was discovered in a strain of Heliothis virescens, the tobacco budworm, that already exhibited a mutation for yellow scale, y. We investigated the inheritance of these visible mutations as candidate markers for transgenesis. Yellow eye was controlled by a single, recessive, autosomal factor, the same type of inheritance previously known for y. Presence of the recombinant mutants with yellow scales with wild type eyes in test crosses indicated independent segregation of genes for these traits. The recombinant class with wild type scales and yellow eyes was completely absent and there was a corresponding increase of the double mutant parental class having yellow scales and yellow eyes. These results indicated that a single factor for yellow eye also controls yellow scales independently of y. This gene was named yes, for yellow eye and scale. We hypothesize that yes controls both eye and scale color through a deficiency in transport of pigment precursors in both the ommochrome and melanin pathways. The unlinked gene y likely controls an enzyme affecting the melanin pathway only. Both y and yes segregated independently of AceIn, acetylcholinesterase insensitivity, and sodium channel hscp, which are genes related to insecticide resistance.

  4. Scaling impacts on environmental controls and spatial heterogeneity of soil organic carbon stocks

    Science.gov (United States)

    Mishra, U.; Riley, W. J.

    2015-07-01

    The spatial heterogeneity of land surfaces affects energy, moisture, and greenhouse gas exchanges with the atmosphere. However, representing the heterogeneity of terrestrial hydrological and biogeochemical processes in Earth system models (ESMs) remains a critical scientific challenge. We report the impact of spatial scaling on environmental controls, spatial structure, and statistical properties of soil organic carbon (SOC) stocks across the US state of Alaska. We used soil profile observations and environmental factors such as topography, climate, land cover types, and surficial geology to predict the SOC stocks at a 50 m spatial scale. These spatially heterogeneous estimates provide a data set with reasonable fidelity to the observations at a sufficiently high resolution to examine the environmental controls on the spatial structure of SOC stocks. We upscaled both the predicted SOC stocks and environmental variables from finer to coarser spatial scales (s = 100, 200, and 500 m and 1, 2, 5, and 10 km) and generated various statistical properties of SOC stock estimates. We found different environmental factors to be statistically significant predictors at different spatial scales. Only elevation, temperature, potential evapotranspiration, and scrub land cover types were significant predictors at all scales. The strengths of control (the median value of geographically weighted regression coefficients) of these four environmental variables on SOC stocks decreased with increasing scale and were accurately represented using mathematical functions (R2 = 0.83-0.97). The spatial structure of SOC stocks across Alaska changed with spatial scale. Although the variance (sill) and unstructured variability (nugget) of the calculated variograms of SOC stocks decreased exponentially with scale, the correlation length (range) remained relatively constant across scale. The variance of predicted SOC stocks decreased with spatial scale over the range of 50 m to ~ 500 m, and remained

  5. Decentralised stabilising controllers for a class of large-scale linear ...

    Indian Academy of Sciences (India)

    Abstract. A simple method for computing decentralised stabilising con- trollers for a class of large-scale (interconnected) linear systems has been developed. Decentralised controls are optimal controls at subsystem level and are generated from the solution of algebraic Riccati equations for decoupled subsystems resulting ...

  6. Anti-control of chaos of single time-scale brushless DC motor.

    Science.gov (United States)

    Ge, Zheng-Ming; Chang, Ching-Ming; Chen, Yen-Sheng

    2006-09-15

    Anti-control of chaos of single time-scale brushless DC motors is studied in this paper. In order to analyse a variety of periodic and chaotic phenomena, we employ several numerical techniques such as phase portraits, bifurcation diagrams and Lyapunov exponents. Anti-control of chaos can be achieved by adding an external constant term or an external periodic term.

  7. Local, distributed topology control for large-scale wireless ad-hoc networks

    NARCIS (Netherlands)

    Nieberg, T.; Hurink, Johann L.

    In this document, topology control of a large-scale, wireless network by a distributed algorithm that uses only locally available information is presented. Topology control algorithms adjust the transmission power of wireless nodes to create a desired topology. The algorithm, named local power

  8. Telerobotic-assisted bone-drilling system using bilateral control with feed operation scaling and cutting force scaling

    Science.gov (United States)

    Kasahara, Yusuke; Kawana, Hiromasa; Usuda, Shin; Ohnishi, Kouhei

    2012-01-01

    Background Drilling is used in the medical field, especially in oral surgery and orthopaedics. In recent years, oral surgery involving dental implants has become more common. However, the risky drilling process causes serious accidents. To prevent these accidents, supporting systems such as robotic drilling systems are required. Methods A telerobotic-assisted drilling system is proposed. An acceleration-based four-channel bilateral control system is implemented in linear actuators in a master–slave system for drill feeding. A reaction force observer is used instead of a force sensor for measuring cutting force. Cutting force transmits from a cutting material to a surgeon, who may feel a static cutting resistance force and vigorous cutting vibrations, via the master–slave system. Moreover, position scaling and force scaling are achieved. Scaling functions are used to achieve precise drilling and hazard detection via force sensation. Results Cutting accuracy and reproducibility of the cutting force were evaluated by angular velocity/position error and frequency analysis of the cutting force, respectively, and errors were > 2.0 rpm and > 0.2 mm, respectively. Spectrum peaks of the cutting vibration were at the theoretical vibration frequencies of 30, 60 and 90 Hz. Conclusions The proposed telerobotic-assisted drilling system achieved precise manipulation of the drill feed and vivid feedback from the cutting force. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22271710

  9. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Fang, Jiakun

    2013-01-01

    This paper presents a simulation model of a wind power plant based on a MW-level variable speed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory. Three different kinds of ancillary frequency control strategies, namely inertia...... emulation, primary frequency control and secondary frequency control, are proposed in order to improve the frequency stability of power systems. The modified IEEE 39-bus test system with a large-scale wind power penetration is chosen as the studied power system. Simulation results show that the proposed...

  10. Fuzzy Adaptive Decentralized Optimal Control for Strict Feedback Nonlinear Large-Scale Systems.

    Science.gov (United States)

    Sun, Kangkang; Sui, Shuai; Tong, Shaocheng

    2017-05-16

    This paper considers the optimal decentralized fuzzy adaptive control design problem for a class of interconnected large-scale nonlinear systems in strict feedback form and with unknown nonlinear functions. The fuzzy logic systems are introduced to learn the unknown dynamics and cost functions, respectively, and a state estimator is developed. By applying the state estimator and the backstepping recursive design algorithm, a decentralized feedforward controller is established. By using the backstepping decentralized feedforward control scheme, the considered interconnected large-scale nonlinear system in strict feedback form is changed into an equivalent affine large-scale nonlinear system. Subsequently, an optimal decentralized fuzzy adaptive control scheme is constructed. The whole optimal decentralized fuzzy adaptive controller is composed of a decentralized feedforward control and an optimal decentralized control. It is proved that the developed optimal decentralized controller can ensure that all the variables of the control system are uniformly ultimately bounded, and the cost functions are the smallest. Two simulation examples are provided to illustrate the validity of the developed optimal decentralized fuzzy adaptive control scheme.

  11. Smart materials-based actuators at the micronano-scale characterization, control, and applications

    CERN Document Server

    2013-01-01

    Smart Materials-Based Actuators at the Micro/Nano-Scale: Characterization, Control, and Applications gives a state of the art of emerging techniques to the characterization and control of actuators based on smart materials working at the micro/nano scale. The book aims to characterize some commonly used structures based on piezoelectric and electroactive polymeric actuators and also focuses on various and emerging techniques employed to control them. This book also includes two of the most emerging topics and applications: nanorobotics and cells micro/nano-manipulation. This book: Provides both theoretical and experimental results Contains complete information from characterization, modeling, identification, control to final applications for researchers and engineers that would like to model, characterize, control and apply their own micro/nano-systems Discusses applications such as microrobotics and their control, design and fabrication of microsystems, microassembly and its automation, nanorobotics and thei...

  12. Impression management ("lie") scales are associated with interpersonally oriented self-control, not other-deception.

    Science.gov (United States)

    Uziel, Liad

    2014-06-01

    This article explores the status of impression management (IM) scales ("lie scales," notably, BIDR-IM) as measures of response bias, offers theory-driven substantive meaning to them, and compares them with self-deception enhancement (SDE). Study 1 (N = 99) compared self-descriptions of actual self and ideal self given in a non-anonymous setting. High similarity indicates self-enhancement. Study 2 (70 dyads) analyzed self-other agreement about IM and SDE. Agreement indicates substantive basis to the scales' scores. Study 3 (N = 182) explored the centrality of self-control in the self-perception of individuals varying in IM and SDE. Study 4 (95 dyads) corroborated self-reports about self-control using informants' reports. In Study 1, IM was associated with relative humility, whereas SDE was associated with self-enhancement. In Study 2, strong self-other agreement was found only for IM, indicating that high IM (but not SDE) is grounded in real-life behavior. In Study 3, self-control was central in the self-perception of high IM and high SDE individuals. In Study 4, strong relations with self-control were corroborated by informants only for IM. IM scales measure substantive content associated with self-control aimed at social adaptation, whereas the SDE scale depicts individuals with a grandiose self-perception, who fail to impress knowledgeable others. © 2013 Wiley Periodicals, Inc.

  13. A revision of the Academic Locus of Control Scale for College Students.

    Science.gov (United States)

    Curtis, Nicholas A; Trice, Ashton D

    2013-06-01

    This study presents a revision of Trice's (1985) Academic Locus of Control Scale for College Students. A principal component analysis involving 322 college students produced four factors including 21 of the original 28 items. Inspection of the seven items not included in the four-factor solution suggested that they could be eliminated on both content and technical grounds. The resulting revised scale was similar to the original scale with respect to its relations with GPA, attendance, and measures of Academic Entitlement, procrastination, depression, and anxiety.

  14. Validity of the Multidimensional Health Locus of Control Scales in American Sign Language

    Science.gov (United States)

    Athale, Ninad; Aldridge, Arianna; Malcarne, Vanessa L.; Nakaji, Melanie; Samady, Waheeda; Sadler, Georgia Robins

    2014-01-01

    Few instruments have been translated and validated for people who use American Sign Language (ASL) as their preferred language. This study examined the reliability and validity of a new ASL version of the widely-used Multidimensional Health Locus of Control (MHLC) scales. Deaf individuals (N = 311) were shown the ASL version via videotape, and their responses were recorded. Confirmatory factor analysis supported the four-factor structure of the MHLC. Scale reliabilities (Cronbach’s alphas) ranged from .60 to .93. There were no apparent gender or ethnic differences. These results provide support for the new ASL version of the MHLC scales. PMID:20511286

  15. Comparisons of optically monitored small-scale stirred tank vessels to optically controlled disposable bag bioreactors

    Directory of Open Access Journals (Sweden)

    Brorson Kurt A

    2009-08-01

    Full Text Available Abstract Background Upstream bioprocesses are extremely complex since living organisms are used to generate active pharmaceutical ingredients (APIs. Cells in culture behave uniquely in response to their environment, thus culture conditions must be precisely defined and controlled in order for productivity and product quality to be reproducible. Thus, development culturing platforms are needed where many experiments can be carried out at once and pertinent scale-up information can be obtained. Results Here we have tested a High Throughput Bioreactor (HTBR as a scale-down model for a lab-scale wave-type bioreactor (CultiBag. Mass transfer was characterized in both systems and scaling based on volumetric oxygen mass transfer coefficient (kLa was sufficient to give similar DO trends. HTBR and CultiBag cell growth and mAb production were highly comparable in the first experiment where DO and pH were allowed to vary freely. In the second experiment, growth and mAb production rates were lower in the HTBR as compared to the CultiBag, where pH was controlled. The differences in magnitude were not considered significant for biological systems. Conclusion Similar oxygen delivery rates were achieved in both systems, leading to comparable culture performance (growth and mAb production across scales and mode of mixing. HTBR model was most fitting when neither system was pH-controlled, providing an information-rich alternative to typically non-monitored mL-scale platforms.

  16. An enhanced hierarchical control strategy for the Internet of Things-based home scale microgrid

    DEFF Research Database (Denmark)

    Guan, Yajuan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2017-01-01

    As the intelligent control and detection technology improving, more and more smart devices/sensors can be used to increase the living standard. In order to integrate the Internet of Things (IoT) with microgrid (MG), an enhanced hierarchical control strategy for IoT-based home scale MG is proposed....... In this sense, the IoT infrastructure can be smoothly integrated with the original MG hierarchical Control theory. The proposed structure will be implemented in an IoT MG laboratory in line with VICINITY project at Aalborg University, Denmark.......As the intelligent control and detection technology improving, more and more smart devices/sensors can be used to increase the living standard. In order to integrate the Internet of Things (IoT) with microgrid (MG), an enhanced hierarchical control strategy for IoT-based home scale MG is proposed...

  17. Singular perturbations and time scales in the design of digital flight control systems

    Science.gov (United States)

    Naidu, Desineni S.; Price, Douglas B.

    1988-01-01

    The results are presented of application of the methodology of Singular Perturbations and Time Scales (SPATS) to the control of digital flight systems. A block diagonalization method is described to decouple a full order, two time (slow and fast) scale, discrete control system into reduced order slow and fast subsystems. Basic properties and numerical aspects of the method are discussed. A composite, closed-loop, suboptimal control system is constructed as the sum of the slow and fast optimal feedback controls. The application of this technique to an aircraft model shows close agreement between the exact solutions and the decoupled (or composite) solutions. The main advantage of the method is the considerable reduction in the overall computational requirements for the evaluation of optimal guidance and control laws. The significance of the results is that it can be used for real time, onboard simulation. A brief survey is also presented of digital flight systems.

  18. Development and validation of the alcohol-related God locus of control scale.

    Science.gov (United States)

    Murray, Thomas S; Goggin, Kathy; Malcarne, Vanessa L

    2006-03-01

    Control beliefs and spirituality appear to be important factors in recovery from alcoholism. However, the integration of these two constructs has received little attention, and the relationship of spiritually related control beliefs to recovery remains unclear. Currently no measures exist to specifically assess these beliefs. To address this need, the Alcohol-Related God Locus of Control scale (AGLOC) was developed. This 12-item self-report measure assesses perceptions of God/Higher Power's role in recovery from alcoholism. The AGLOC was administered to 144 recovering alcoholics attending Alcoholics Anonymous meetings. Exploratory factor analysis yielded a two-factor solution with one factor related to attributions of God control over initial cessation of drinking (Cessation) and the other factor related to attributions of God control over one's continued maintenance of sobriety (Maintenance). Both subscales and the overall scale demonstrated adequate to high internal consistency. Demonstrating convergent and discriminant validity, the total AGLOC scale and the Cessation subscale were significantly but moderately correlated with spirituality (both frequency and importance), and independent of perceptions of internal control over drinking. Maintenance subscale scores were inversely associated with internal drinking-related scores and were not associated with spiritual importance or frequency of spiritual practice. Findings support the utility of this instrument for the assessment of alcohol-related God/Higher Power locus of control beliefs in an alcoholic population and suggest the importance of further research on changes in alcohol-related God control beliefs throughout the course of recovery.

  19. Adaptive Fuzzy Sliding Mode Control for a Model-Scaled Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Amir Razzaghian

    2016-11-01

    Full Text Available This paper presents a novel Adaptive Fuzzy Sliding Mode Controller (AFSMC for a model-scaled unmanned helicopter as real nonlinear plant. First, in order to efficient control law design, the nonlinear model of the helicopter is reformulated as an affine nonlinear system. To do this aim, a Dynamic Inverter (DI is introduced as a bijective function. The proposed DI is used to interconnect the helicopter actuators' main inputs to the helicopter dynamic inputs. Then, AFSMC is designed to control it, and the asymptotic stability of the closed loop system is proved using Lyapunov stability theorem. To verify the merits of the proposed controller, it is compared with traditional sliding mode control system. Simulation results confirmed that the controller as a robust and stable control method has desired controlling performance and well cope with the undesirable chattering phenomenon.

  20. Adaptive Control of a Utility-Scale Wind Turbine Operating in Region 3

    Science.gov (United States)

    Frost, Susan A.; Balas, Mark J.; Wright, Alan D.

    2009-01-01

    Adaptive control techniques are well suited to nonlinear applications, such as wind turbines, which are difficult to accurately model and which have effects from poorly known operating environments. The turbulent and unpredictable conditions in which wind turbines operate create many challenges for their operation. In this paper, we design an adaptive collective pitch controller for a high-fidelity simulation of a utility scale, variable-speed horizontal axis wind turbine. The objective of the adaptive pitch controller in Region 3 is to regulate generator speed and reject step disturbances. The control objective is accomplished by collectively pitching the turbine blades. We use an extension of the Direct Model Reference Adaptive Control (DMRAC) approach to track a reference point and to reject persistent disturbances. The turbine simulation models the Controls Advanced Research Turbine (CART) of the National Renewable Energy Laboratory in Golden, Colorado. The CART is a utility-scale wind turbine which has a well-developed and extensively verified simulator. The adaptive collective pitch controller for Region 3 was compared in simulations with a bas celliansesical Proportional Integrator (PI) collective pitch controller. In the simulations, the adaptive pitch controller showed improved speed regulation in Region 3 when compared with the baseline PI pitch controller and it demonstrated robustness to modeling errors.

  1. Comparing the Fullerton Advanced Balance Scale with the Mini-BESTest and Berg Balance Scale to assess postural control in patients with Parkinson disease.

    Science.gov (United States)

    Schlenstedt, Christian; Brombacher, Stephanie; Hartwigsen, Gesa; Weisser, Burkhard; Möller, Bettina; Deuschl, Günther

    2015-02-01

    To validate the Fullerton Advanced Balance (FAB) Scale for patients with idiopathic Parkinson disease (PD); and to compare the FAB Scale with the Mini-Balance Evaluation Systems Test (Mini-BESTest) and Berg Balance Scale (BBS). Observational study to assess concurrent validity, test-retest, and interrater reliability of the FAB Scale in patients with PD and to compare the distribution of the scale with the Mini-BESTest and BBS. University hospital in an urban community. Patients with idiopathic PD (N=85; Hoehn and Yahr stages 1-4). Not applicable. FAB Scale, Mini-BESTest, BBS, timed Up and Go test, Unified Parkinson's Disease Rating Scale, and visual analog scale. Interrater (3 raters) and test-retest (3±1 d) reliability were high for all scales (ICCs≥.95). The FAB Scale was highly correlated with the Mini-BESTest (Spearman ρ=.87) and timed Up and Go test item of the Mini-BESTest (Spearman ρ=.83). In contrast with the BBS, the FAB Scale and Mini-BESTest have only minimal ceiling effects. The FAB Scale demonstrated the most symmetric distribution when compared with the Mini-BESTest and BBS (skewness: FAB scale: -.54; Mini-BESTest: -1.07; BBS: -2.14). The FAB Scale is a valid and reliable tool to assess postural control in patients with PD. No ceiling effect was noted for the FAB Scale. Although the items of the FAB Scale are more detailed when compared with the Mini-BESTest, interrater and test-retest reliability were excellent. The scale is a promising tool to detect small changes of the postural control system in individuals with PD. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  2. Lateral Comparative Investigation of Stromatolites: Astrobiological Implications and Assessment of Scales of Control

    Science.gov (United States)

    Ibarra, Yadira; Corsetti, Frank A.

    2016-04-01

    The processes that govern the formation of stromatolites, structures that may represent macroscopic manifestation of microbial processes and a clear target for astrobiological investigation, occur at various scales (local versus regional), yet determining their relative importance remains a challenge, particularly for ancient deposits and/or if similar deposits are discovered elsewhere in the Solar System. We build upon the traditional multiscale level approach of investigation (micro-, meso-, macro-, mega-) by including a lateral comparative investigational component of fine- to large-scale features to determine the relative significance of local and/or nonlocal controls on stromatolite morphology, and in the process, help constrain the dominant influences on microbialite formation. In one example of lateral comparative investigation, lacustrine microbialites from the Miocene Barstow Formation (California) display two main mesofabrics: (1) micritic bands that drastically change in thickness and cannot directly be traced between adjacent decimeter-scale subunits and (2) sparry fibrous layers that are strikingly consistent across subunits, suggesting the formation of sparry fibrous layers was influenced by a process larger than the length scale between the subunits (likely lake chemistry). Microbialites from the uppermost Triassic Cotham Member, United Kingdom, occur as meter-scale mounds and contain a characteristic succession of laminated and dendrolitic mesofabrics. The same succession of laminated/dendrolitic couplets can be traced, not only from mound to mound, but over 100 km, indicating a regional-scale influence on very small structures (microns to centimeters) that would otherwise not be apparent without the lateral comparative approach, and demonstrating that the scale of the feature does not necessarily scale with the scope of the process. Thus, the combination of lateral comparative investigations and multiscale analyses can provide an effective approach

  3. Toward city-scale water quality control: building a theory for smart stormwater systems

    Science.gov (United States)

    Kerkez, B.; Mullapudi, A. M.; Wong, B. P.

    2016-12-01

    Urban stormwater systems are rarely designed as actual systems. Rather, it is often assumed that individual Best Management Practices (BMPs) will add up to achieve desired watershed outcomes. Given the rise of BMPs and green infrastructure, we ask: does doing "best" at the local scale guarantee the "best" at the global scale? Existing studies suggest that the system-level performance of distributed stormwater practices may actually adversely impact watersheds by increasing downstream erosion and reducing water quality. Optimizing spatial placement may not be sufficient, however, since precipitation variability and other sources of uncertainty can drive the overall system into undesirable states. To that end, it is also important to control the temporal behavior of the system, which can be achieved by equipping stormwater elements (ponds, wetlands, basins, bioswales, etc.) with "smart" sensors and valves. Rather than building new infrastructure, this permits for existing assets to be repurposed and controlled to adapt to individual storm events. While we have learned how to build and deploy the necessary sensing and control technologies, we do not have a framework or theory that combines our knowledge of hydrology, hydraulics, water quality and control. We discuss the development of such a framework and investigate how existing water domain knowledge can be transferred into a system-theoretic context to enable real-time, city-scale stormwater control. We apply this framework to water quality control in an urban watershed in southeast Michigan, which has been heavily instrumented and retrofitted for control over the past year.

  4. Control of modular multilevel converters based on time-scale analysis and orthogonal functions

    DEFF Research Database (Denmark)

    Zarri, L.; Tani, A.; Mengoni, M.

    2014-01-01

    Modular multilevel converter (MMC) is a promising multilevel topology for high-voltage applications that has been developed in recent years. The control of MMCs has been analyzed in detail in many papers, showing that the converter capacitors can be kept charged and balanced by controlling...... current is still a complex task and cannot be fully tackled with traditional linear control techniques. In this paper a multiple time-scale analysis is proposed to determine an approximated model of the MMC that can be used to solve the control problem of the capacitor voltages. In addition, it is shown...

  5. Model Predictive Control for Flexible Power Consumption of Large-Scale Refrigeration Systems

    DEFF Research Database (Denmark)

    Shafiei, Seyed Ehsan; Stoustrup, Jakob; Rasmussen, Henrik

    2014-01-01

    A model predictive control (MPC) scheme is introduced to directly control the electrical power consumption of large-scale refrigeration systems. Deviation from the baseline of the consumption is corresponded to the storing and delivering of thermal energy. By virtue of such correspondence......, the control method can be employed for regulating power services in the smart grid. The proposed scheme contains the control of cooling capacity as well as optimizing the efficiency factor of the system, which is in general a nonconvex optimization problem. By introducing a fictitious manipulated variable......, and novel incorporation of the evaporation temperature set-point into optimization problem, the convex optimization problem is formulated within the MPC scheme. The method is applied to a simulation benchmark of large-scale refrigeration systems including several medium and low temperature cold reservoirs....

  6. Rethinking Social Desirability Scales: From Impression Management to Interpersonally Oriented Self-Control.

    Science.gov (United States)

    Uziel, Liad

    2010-05-01

    Social desirability (specifically, impression management) scales are widely used by researchers and practitioners to screen individuals who bias self-reports in a self-favoring manner. These scales also serve to identify individuals at risk for psychological and health problems. The present review explores the evidence with regard to the ability of these scales to achieve these objectives. In the first part of the review, I present six criteria to evaluate impression management scales and conclude that they are unsatisfactory as measures of response style. Next, I explore what individual differences in impression management scores actually do measure. I compare two approaches: a defensiveness approach, which argues that these scales measure defensiveness that stems from vulnerable self-esteem, and an adjustment approach, which suggests that impression management is associated with personal well-being and interpersonal adjustment. Data from a wide variety of fields including social behavior, affect and well-being, health, and job performance tend to favor the adjustment approach. Finally, I argue that scales measuring impression management should be redefined as measures of interpersonally oriented self-control that identify individuals who demonstrate high levels of self-control, especially in social contexts. © The Author(s) 2010.

  7. Geophysical Evidence for Abiotic Controls on Peatland Patterning at Multiple Scales

    Science.gov (United States)

    Nolan, J.; Slater, L.; Glaser, P.; Comas, X.; O'Brien, M.

    2007-12-01

    The autogenic and allogenic controls on the formation of distinctive and dramatic vegetation patterning found in northern peatlands remain unclear. Groundwater model studies and investigations using point measurements lack intensive data over multiple scales, primarily due to the intensive time required and difficult logistics required to work in these remote ecosystems. We provide geophysical evidence that lithological controls on vegetation patterning exist at multiple scales in ombrotrophic peatlands of northern Minnesota and Maine. Surveys using electrical imaging methods (including resistivity, induced polarization, and ground penetrating radar) at sites in the Red Lake Peatland Complex (160 km2), as well as Kanokolus Bog (1.65 km2) and the Caribou Bog Peatland Complex (22 km2) in Maine reveal sharp vegetation gradients coinciding with changes in the mineral soil lithology. In contrast, large-scale, continuous, patterned zones found in the Red lake Complex coincide with strikingly uniform mineral soil lithology as inferred from the geophysical images. Small-scale (0.3 km2) vegetation patterns observed in Caribou Bog also coincide with small scale lithologic changes in both the mineral and organic deposits. These results provide evidence that the subsurface hydrogeologic framework regulates vegetation patterning in peatlands across multiple scales, presumably by regulating (1) the supply of mineral solutes to the surface vegetation water, and (2) water levels within the organic soil.

  8. Climate, Water, and Human Health: Large Scale Hydroclimatic Controls in Forecasting Cholera Epidemics

    Science.gov (United States)

    Akanda, A. S.; Jutla, A. S.; Islam, S.

    2009-12-01

    Despite ravaging the continents through seven global pandemics in past centuries, the seasonal and interannual variability of cholera outbreaks remain a mystery. Previous studies have focused on the role of various environmental and climatic factors, but provided little or no predictive capability. Recent findings suggest a more prominent role of large scale hydroclimatic extremes - droughts and floods - and attempt to explain the seasonality and the unique dual cholera peaks in the Bengal Delta region of South Asia. We investigate the seasonal and interannual nature of cholera epidemiology in three geographically distinct locations within the region to identify the larger scale hydroclimatic controls that can set the ecological and environmental ‘stage’ for outbreaks and have significant memory on a seasonal scale. Here we show that two distinctly different, pre and post monsoon, cholera transmission mechanisms related to large scale climatic controls prevail in the region. An implication of our findings is that extreme climatic events such as prolonged droughts, record floods, and major cyclones may cause major disruption in the ecosystem and trigger large epidemics. We postulate that a quantitative understanding of the large-scale hydroclimatic controls and dominant processes with significant system memory will form the basis for forecasting such epidemic outbreaks. A multivariate regression method using these predictor variables to develop probabilistic forecasts of cholera outbreaks will be explored. Forecasts from such a system with a seasonal lead-time are likely to have measurable impact on early cholera detection and prevention efforts in endemic regions.

  9. Interaural Level Difference Dependent Gain Control and Synaptic Scaling Underlying Binaural Computation

    Science.gov (United States)

    Xiong, Xiaorui R.; Liang, Feixue; Li, Haifu; Mesik, Lukas; Zhang, Ke K.; Polley, Daniel B.; Tao, Huizhong W.; Xiao, Zhongju; Zhang, Li I.

    2013-01-01

    Binaural integration in the central nucleus of inferior colliculus (ICC) plays a critical role in sound localization. However, its arithmetic nature and underlying synaptic mechanisms remain unclear. Here, we showed in mouse ICC neurons that the contralateral dominance is created by a “push-pull”-like mechanism, with contralaterally dominant excitation and more bilaterally balanced inhibition. Importantly, binaural spiking response is generated apparently from an ipsilaterally-mediated scaling of contralateral response, leaving frequency tuning unchanged. This scaling effect is attributed to a divisive attenuation of contralaterally-evoked synaptic excitation onto ICC neurons with their inhibition largely unaffected. Thus, a gain control mediates the linear transformation from monaural to binaural spike responses. The gain value is modulated by interaural level difference (ILD) primarily through scaling excitation to different levels. The ILD-dependent synaptic scaling and gain adjustment allow ICC neurons to dynamically encode interaural sound localization cues while maintaining an invariant representation of other independent sound attributes. PMID:23972599

  10. Controlling Mobility in Perovskite Oxides by Ferroelectric Modulation of Atomic-Scale Interface Structure.

    Science.gov (United States)

    Malashevich, Andrei; Marshall, Matthew S J; Visani, Cristina; Disa, Ankit S; Xu, Haichao; Walker, Frederick J; Ahn, Charles H; Ismail-Beigi, Sohrab

    2017-12-26

    Coherent and epitaxial interfaces permit the realization of electric field driven devices controlled by atomic-scale structural and electronic effects at interfaces. Compared to conventional field effect devices where channel conductivity is modulated by carrier density modification, the propagation of atomic-scale distortions across an interface can control the atomic scale bonding, interatomic electron tunneling rates and thus the mobility of the channel material. We use first-principles theory to design an atomically abrupt epitaxial perovskite heterostructure involving an oxide ferroelectric (PbZr0.2Ti0.8O3) and conducting oxide channel (LaNiO3) where coupling of polar atomic motions to structural distortions can induce large, reversible changes in the channel mobility. We fabricate and characterize the heterostructure and measure record values, larger than 1000%, for the conductivity modulation. Our results describe how purely interfacial effects can be engineered to deliver unique electronic device properties and large responses to external fields.

  11. Robust Nonlinear Control Based on Disturbance Observer for a Small-Scale Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Amir Razzaghian

    2017-09-01

    Full Text Available A robust nonlinear controller based on disturbance observer for the trajectory tracking control of a small-scale unmanned helicopter with nonlinear structure under external disturbances and parameter uncertainties is designed. The control objective is to let the helicopter track a predefined trajectory. The proposed robust nonlinear controller is based on the backstepping sliding mode control technique which combines both the capabilities of backstepping control and sliding mode control. The control performance developed based on a time-varying disturbance observer. In order to obtain an efficient control law design, the nonlinear model of the helicopter is reformulated as an affine nonlinear system. The mathematical proof using Lyapunov stability theorem shows that the closed loop system is asymptotically stable in the presence of this controller. To verify the robustness and stability of the proposed controller, it is compared with conventional sliding mode controller. The chattering phenomenon is attenuated significantly and the tracking error is also alleviated. The simulation results confirm the desirable performance of proposed robust nonlinear controller.

  12. Controlling Barium Sulphate Scale Deposition Problems in an unbleached Kraft Paper Mill

    CSIR Research Space (South Africa)

    Sithole, Bruce

    2015-06-01

    Full Text Available /phosphonates and polyacrylates were effective in reducing and controlling the scale deposit problems. Institution of these measures led to a cleaner paper machine that required far fewer boil outs than before. In addition, productivity improved and the fisheye defects...

  13. High-performance small-scale solvers for linear Model Predictive Control

    DEFF Research Database (Denmark)

    Frison, Gianluca; Sørensen, Hans Henrik Brandenborg; Dammann, Bernd

    2014-01-01

    In Model Predictive Control (MPC), an optimization problem needs to be solved at each sampling time, and this has traditionally limited use of MPC to systems with slow dynamic. In recent years, there has been an increasing interest in the area of fast small-scale solvers for linear MPC...

  14. Industrial-scale radio frequency treatments for insect control in lentils

    Science.gov (United States)

    Radio frequency (RF) treatments are considered to be a potential postharvest technology for disinfesting legumes of internal seed pests such as the cowpea weevil. After treatment protocols are shown to control postharvest insects without significant quality degradation, it is important to scale-up l...

  15. Quantification of protein-derived thiols during atmosphere-controlled brewing in laboratory scale

    DEFF Research Database (Denmark)

    Murmann, Anne Nordmark; Andersen, Preben; Mauch, Alexander

    2016-01-01

    An atmosphere-controlled brewing system was built to study thiol oxidation during brewing in laboratory scale under conditions with limited oxygen exposure. Quantification of free and total thiols and protein showed that thiols were lost during wort boiling possibly owing to protein precipitation...

  16. Interactive Modeling, Simulation and Control of Large-Scale Crowds and Traffic

    Science.gov (United States)

    Lin, Ming C.; Guy, Stephen; Narain, Rahul; Sewall, Jason; Patil, Sachin; Chhugani, Jatin; Golas, Abhinav; van den Berg, Jur; Curtis, Sean; Wilkie, David; Merrell, Paul; Kim, Changkyu; Satish, Nadathur; Dubey, Pradeep; Manocha, Dinesh

    We survey some of our recent work on interactive modeling, simulation, and control of large-scale crowds and traffic for urban scenes. The driving applications of our work include real-time simulation for computer games, virtual environments, and avatar-based online 3D social networks. We also present some preliminary results and proof-of-concept demonstrations.

  17. Scaling Academic Planning in Community College: A Randomized Controlled Trial. REL 2017-204

    Science.gov (United States)

    Visher, Mary G.; Mayer, Alexander K.; Johns, Michael; Rudd, Timothy; Levine, Andrew; Rauner, Mary

    2016-01-01

    Community college students often lack an academic plan to guide their choices of coursework to achieve their educational goals, in part because counseling departments typically lack the capacity to advise students at scale. This randomized controlled trial tests the impact of guaranteed access to one of two alternative counseling sessions (group…

  18. Dimensional Control in Corner Lithography for Wafer-Scale Fabrication of Nano-Apertures

    NARCIS (Netherlands)

    Burouni, N.; Berenschot, Johan W.; Elwenspoek, Michael Curt; Tas, Niels Roelof

    2011-01-01

    In this paper we investigate a new method to fabricate 3D-oriented nanostructures in wafer scale, and apply it to fabricate a nano-apertures at the apex of a pyramid. A number of new technologies require the use of apertures to serve as electrical, nano fluidic or optical probes. Controlling the

  19. Adaptive Fault-Tolerant Control of Uncertain Nonlinear Large-Scale Systems With Unknown Dead Zone.

    Science.gov (United States)

    Chen, Mou; Tao, Gang

    2016-08-01

    In this paper, an adaptive neural fault-tolerant control scheme is proposed and analyzed for a class of uncertain nonlinear large-scale systems with unknown dead zone and external disturbances. To tackle the unknown nonlinear interaction functions in the large-scale system, the radial basis function neural network (RBFNN) is employed to approximate them. To further handle the unknown approximation errors and the effects of the unknown dead zone and external disturbances, integrated as the compounded disturbances, the corresponding disturbance observers are developed for their estimations. Based on the outputs of the RBFNN and the disturbance observer, the adaptive neural fault-tolerant control scheme is designed for uncertain nonlinear large-scale systems by using a decentralized backstepping technique. The closed-loop stability of the adaptive control system is rigorously proved via Lyapunov analysis and the satisfactory tracking performance is achieved under the integrated effects of unknown dead zone, actuator fault, and unknown external disturbances. Simulation results of a mass-spring-damper system are given to illustrate the effectiveness of the proposed adaptive neural fault-tolerant control scheme for uncertain nonlinear large-scale systems.

  20. Financial analysis of brucellosis control for small-scale goat farming in the Bajio Region, Mexico

    NARCIS (Netherlands)

    Oseguera Montiel, D.; Bruce, M.; Frankena, K.; Udo, H.M.J.; Zijpp, van der A.J.; Rushton, J.

    2015-01-01

    Brucellosis is an endemic disease in small-scale goat husbandry systems in Mexico. It is a zoonosis and the economic consequences can be large, although estimates are not available for the Mexican goat sector. Our objective was to conduct a financial analysis of brucellosis control in a prominent

  1. Multi-scale optical metrology for the quality control of polymer microfluidic systems

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2009-01-01

    Micro injection moulding is a replication technology enabling large scale production of polymer-based micro products. To this respect, optical measuring technologies were selected to perform the quality control of a polymer micro-component: an optical coordinate measuring machine (CMM) and a whit...

  2. Economic Model Predictive Control for Large-Scale and Distributed Energy Systems

    DEFF Research Database (Denmark)

    Standardi, Laura

    Sources (RESs) in the smart grids is increasing. These energy sources bring uncertainty to the production due to their fluctuations. Hence,smart grids need suitable control systems that are able to continuously balance power production and consumption.  We apply the Economic Model Predictive Control (EMPC.......  The mathematical model of the large-scale energy system embodies the decoupled dynamics of each power units. Moreover,all units of the grid contribute to the overall power production. Economic Model Predictive Control (EMPC) This control strategy is an extension of the Model Predictive Control (MPC......In this thesis, we consider control strategies for large and distributed energy systems that are important for the implementation of smart grid technologies.  An electrical grid has to ensure reliability and avoid long-term interruptions in the power supply. Moreover, the share of Renewable Energy...

  3. Robust Control for Lateral and Longitudinal Channels of Small-Scale Unmanned Helicopters

    Directory of Open Access Journals (Sweden)

    Bao Feng

    2015-01-01

    Full Text Available Lateral and longitudinal channels are two closely related channels whose control stability influences flight performance of small-scale unmanned helicopters directly. This paper presents a robust control approach for lateral and longitudinal channels in the presence of parameter uncertainties and exogenous disturbances. The proposed control approach is performed by two steps. First, by performing system identification in frequency domain, system model of lateral and longitudinal channels can be accurately identified. Then, a robust H∞ state feedback controller is designed to stabilize the helicopter in lateral and longitudinal channels simultaneously under extraneous disturbances situation. The proposed approach takes advantages that it reduces order of the controller by preestimating some parameters (like flapping angles without sacrificing control accuracy. Numerical results show the reliability and effectiveness of the proposed method.

  4. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Bench-scale Testbed Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kisner, Roger A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Drira, Anis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Reed, Frederick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Embedded instrumentation and control systems that can operate in extreme environments are challenging due to restrictions on sensors and materials. As a part of the Department of Energy's Nuclear Energy Enabling Technology cross-cutting technology development programs Advanced Sensors and Instrumentation topic, this report details the design of a bench-scale embedded instrumentation and control testbed. The design goal of the bench-scale testbed is to build a re-configurable system that can rapidly deploy and test advanced control algorithms in a hardware in the loop setup. The bench-scale testbed will be designed as a fluid pump analog that uses active magnetic bearings to support the shaft. The testbed represents an application that would improve the efficiency and performance of high temperature (700 C) pumps for liquid salt reactors that operate in an extreme environment and provide many engineering challenges that can be overcome with embedded instrumentation and control. This report will give details of the mechanical design, electromagnetic design, geometry optimization, power electronics design, and initial control system design.

  5. A Novel Hierarchical Control Strategy for the Internet of Things based Home Scale Microgrid

    DEFF Research Database (Denmark)

    Guan, Yajuan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2017-01-01

    As the intelligent control and detection technology improving, more and more smart devices/sensors can be used to increase the living standard. In order to integrate the Internet of Things (IoT) with microgrid (MG), an enhanced hierarchical control strategy for IoT-based home scale MG is proposed....... In this sense, the IoT infrastructure can be smoothly integrated with the original MG hierarchical Control theory. The proposed structure will be implemented in an IoT MG laboratory in line with VICINITY project at Aalborg University, Denmark....

  6. RAID-2: Design and implementation of a large scale disk array controller

    Science.gov (United States)

    Katz, R. H.; Chen, P. M.; Drapeau, A. L.; Lee, E. K.; Lutz, K.; Miller, E. L.; Seshan, S.; Patterson, D. A.

    1992-01-01

    We describe the implementation of a large scale disk array controller and subsystem incorporating over 100 high performance 3.5 inch disk drives. It is designed to provide 40 MB/s sustained performance and 40 GB capacity in three 19 inch racks. The array controller forms an integral part of a file server that attaches to a Gb/s local area network. The controller implements a high bandwidth interconnect between an interleaved memory, an XOR calculation engine, the network interface (HIPPI), and the disk interfaces (SCSI). The system is now functionally operational, and we are tuning its performance. We review the design decisions, history, and lessons learned from this three year university implementation effort to construct a truly large scale system assembly.

  7. Intelligent control of neurosurgical robot MM-3 using dynamic motion scaling.

    Science.gov (United States)

    Ko, Sunho; Nakazawa, Atsushi; Kurose, Yusuke; Harada, Kanako; Mitsuishi, Mamoru; Sora, Shigeo; Shono, Naoyuki; Nakatomi, Hirofumi; Saito, Nobuhito; Morita, Akio

    2017-05-01

    OBJECTIVE Advanced and intelligent robotic control is necessary for neurosurgical robots, which require great accuracy and precision. In this article, the authors propose methods for dynamically and automatically controlling the motion-scaling ratio of a master-slave neurosurgical robotic system to reduce the task completion time. METHODS Three dynamic motion-scaling modes were proposed and compared with the conventional fixed motion-scaling mode. These 3 modes were defined as follows: 1) the distance between a target point and the tip of the slave manipulator, 2) the distance between the tips of the slave manipulators, and 3) the velocity of the master manipulator. Five test subjects, 2 of whom were neurosurgeons, sutured 0.3-mm artificial blood vessels using the MM-3 neurosurgical robot in each mode. RESULTS The task time, total path length, and helpfulness score were evaluated. Although no statistically significant differences were observed, the mode using the distance between the tips of the slave manipulators improves the suturing performance. CONCLUSIONS Dynamic motion scaling has great potential for the intelligent and accurate control of neurosurgical robots.

  8. Can stormwater control measures restore altered urban flow regimes at the catchment scale?

    Science.gov (United States)

    Li, Congying; Fletcher, Tim D.; Duncan, Hugh P.; Burns, Matthew J.

    2017-06-01

    Over the last 20-30 years, there has been an evolution in urban stormwater management towards the use of stormwater control measures (SCMs) at or near the source of the runoff. These approaches aim to protect or restore natural elements of the flow regime. However, evidence of the success of such approaches is to date limited. We reviewed attempts to both model and monitor the catchment-scale hydrological consequences of SCMs. While many catchment-scale studies on the hydrologic effects of SCMs are based on computer simulation, these modeling approaches are limited by many uncertainties. The few existing monitoring studies provide early indications of the potential of SCMs to deliver more natural flow regimes, but many questions remain. There is an urgent need for properly monitored studies that aim to assess the hydrologic effects of SCMs at the catchment scale. In future monitoring studies, these hydrologic effects need to be characterized using appropriate flow metrics at a range of scales (from site scale to catchment scale), and changes to flow metrics by SCMs need to be assessed using robust statistical methods. Such studies will give confidence to stormwater and river managers of the feasibility and benefits of "low impact" approaches to stormwater management.

  9. Dynamic model of frequency control in Danish power system with large scale integration of wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2013-01-01

    This work evaluates the impact of large scale integration of wind power in future power systems when 50% of load demand can be met from wind power. The focus is on active power balance control, where the main source of power imbalance is an inaccurate wind speed forecast. In this study, a Danish...... power system model with large scale of wind power is developed and a case study for an inaccurate wind power forecast is investigated. The goal of this work is to develop an adequate power system model that depicts relevant dynamic features of the power plants and compensates for load generation...

  10. Regional-scale controls of periglacial rockfalls (Turtmann valley, Swiss Alps)

    Science.gov (United States)

    Messenzehl, Karoline; Hoffmann, Thomas; Meyer, Hanna; Dikau, Richard

    2015-04-01

    Rockfalls are among the most hazardous processes in mountain regions and of major importance for landform evolution and sediment budgets. The rockfall activity varies significantly in space and time, driven by the complex interplay between locally dynamic variables (i.e. discontinuities, freeze-thaw processes) as well as system inherent predisposing factors dominating at a regional scale. Many studies focus on small-scale triggering conditions for rockfalls, but the effects of regional-scale controls leading to a basic instability of alpine rockwalls, such as topo-climatic settings, lithology and i.e. tectonic structures as well as paraglacial adjustments, are poorly understood. In this study, we aim to understand the role of regional-scale controls of rockfalls in the Turtmann Valley, which covers 110 km2 in the Swiss Alps. Based on an inventory of 220 talus slopes (Otto et al. 2009), rockfall source areas were determined and their causal relationship between ten different prediction variables was assessed. By combining two multivariate statistical models, we (i) explained the spatial pattern of rockfalls, (ii) evaluated the relative importance of potential predisposing factors (iii) and discuss these regional-scale controls in the light of the local-scale geomorphic and rock mechanical settings. Major finding are: (i) A stepwise logistic regression (LR) based on principal components and a random forests (RF) model were performed and validated using a 75%-subset of the rockfall source areas. Given the area under the ROC curves for both approaches, LR: 0.92, RF: 0.99, respectively, the RF model performs slightly better to explain the large-scale variability of rockfalls in our study area. (ii) Both, the LR and RF model reveal that lithology and joint orientation have the strongest causal influence on rockfalls at regional scale. In contrast, topo-climatic factors (elevation, slope, solar radiation) might be of secondary importance. Additionally, the regional

  11. Time scale analysis of a closed-loop discrete optimal control system

    Science.gov (United States)

    Naidu, D. S.; Price, D. B.

    1986-01-01

    A two-time scale discrete control system is considered. The closed-loop optimal linear quadratic (LQ) regulator for the system requires the solution of a full-order algebraic matrix Riccati equation. Alternatively, the original system is decomposed into reduced-order slow and fast subsystems. The closed-loop optimal control of the subsystems requires the solution of two algebraic matrix Riccati equations of order lower than that required for the full-order system. A composite, closed-loop suboptimal control is created from the sum of the slow and fast feedback optimal controls. Numerical results obtained for an aircraft model show a very close agreement between the exact (optimal) solutions and computationally simpler composite (suboptimal) solutions. The main advantage of the method is the considerable reduction in the overall computational requirements for the closed-loop optimal control of digital flight systems.

  12. The revising of the Tangney Self-Control Scale for Chinese students.

    Science.gov (United States)

    Unger, Alexander; Bi, Chongzeng; Xiao, Ying-Ying; Ybarra, Oscar

    2016-06-01

    Recent studies have characterized self-control as a vital psychological variable that helps explain various problems. Tangney's Self-Control Scale (SCS) is a self-report measurement to assess individual differences in traits of self-control. It has gained popularity in social and psychological science research. In China, there are a few Chinese-version scales measuring general self-control, which can be applied to college students. The purposes of the present study were to evaluate: (a) the psychometric properties of the Chinese version of Tangney's SCS using confirmatory factor analysis, and (b) whether higher scores on the scale correlated with positive outcomes in China. The final sample in this study consisted of 371 Chinese college students aged 17-23 years. The Full SCS and Brief SCS were both found to have a reasonable fitness, which also had satisfactory internal consistencies and a high correlation. Higher scores on the SCS correlated with higher self-esteem, extraversion, better harmony in interpersonal relationships and an appropriate anger expression, less impulsiveness, and state and trait anger. The test-retest reliability was confirmed in two additional samples. Tangney's SCS could be used in China. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  13. Versatile synchronized real-time MEG hardware controller for large-scale fast data acquisition.

    Science.gov (United States)

    Sun, Limin; Han, Menglai; Pratt, Kevin; Paulson, Douglas; Dinh, Christoph; Esch, Lorenz; Okada, Yoshio; Hämäläinen, Matti

    2017-05-01

    Versatile controllers for accurate, fast, and real-time synchronized acquisition of large-scale data are useful in many areas of science, engineering, and technology. Here, we describe the development of a controller software based on a technique called queued state machine for controlling the data acquisition (DAQ) hardware, continuously acquiring a large amount of data synchronized across a large number of channels (>400) at a fast rate (up to 20 kHz/channel) in real time, and interfacing with applications for real-time data analysis and display of electrophysiological data. This DAQ controller was developed specifically for a 384-channel pediatric whole-head magnetoencephalography (MEG) system, but its architecture is useful for wide applications. This controller running in a LabVIEW environment interfaces with microprocessors in the MEG sensor electronics to control their real-time operation. It also interfaces with a real-time MEG analysis software via transmission control protocol/internet protocol, to control the synchronous acquisition and transfer of the data in real time from >400 channels to acquisition and analysis workstations. The successful implementation of this controller for an MEG system with a large number of channels demonstrates the feasibility of employing the present architecture in several other applications.

  14. Versatile synchronized real-time MEG hardware controller for large-scale fast data acquisition

    Science.gov (United States)

    Sun, Limin; Han, Menglai; Pratt, Kevin; Paulson, Douglas; Dinh, Christoph; Esch, Lorenz; Okada, Yoshio; Hämäläinen, Matti

    2017-05-01

    Versatile controllers for accurate, fast, and real-time synchronized acquisition of large-scale data are useful in many areas of science, engineering, and technology. Here, we describe the development of a controller software based on a technique called queued state machine for controlling the data acquisition (DAQ) hardware, continuously acquiring a large amount of data synchronized across a large number of channels (>400) at a fast rate (up to 20 kHz/channel) in real time, and interfacing with applications for real-time data analysis and display of electrophysiological data. This DAQ controller was developed specifically for a 384-channel pediatric whole-head magnetoencephalography (MEG) system, but its architecture is useful for wide applications. This controller running in a LabVIEW environment interfaces with microprocessors in the MEG sensor electronics to control their real-time operation. It also interfaces with a real-time MEG analysis software via transmission control protocol/internet protocol, to control the synchronous acquisition and transfer of the data in real time from >400 channels to acquisition and analysis workstations. The successful implementation of this controller for an MEG system with a large number of channels demonstrates the feasibility of employing the present architecture in several other applications.

  15. Patient perceptions regarding benefits of single visit scale and polish: a randomised controlled trial.

    Science.gov (United States)

    Jones, Clare; Macfarlane, Tatiana V; Milsom, Keith M; Ratcliffe, Philip; Wyllie, Annette; Tickle, Martin

    2013-10-03

    Single visit scale and polish is frequently carried out in dental practices however there is little evidence to support (or refute) its clinical effectiveness. The purpose of this research was to compare patient-reported outcomes between groups receiving a scale and polish at 6-, 12-, and 24-month intervals. Outcomes recorded included participants' subjective assessment of their oral cleanliness; the perceived importance of scale and polish for oral health and aesthetics; and frequency at which this treatment is required. A practice-based randomised control trial was undertaken, with a 24-month follow-up period. Participants were healthy adults with no significant periodontal disease (BPE codes polish at 6-, 12-, or 24-month intervals. Patient-reported outcomes were recorded at baseline and follow-up. Oral cleanliness was reported using a 5-point scale and recorded by examiners blinded to trial group allocation. A self-completed questionnaire enabled participants to report perceived importance of scale and polish (5-point scale), and required frequency of treatment (6-point scale). The main hypothesis was that participants receiving 6-monthly scale and polish would report higher levels of oral cleanliness compared to participants receiving scale and polish at 12- and 24-month intervals. 369 participants were randomised: 125 to the 6-month group; 122 to the 12-month group; and 122 to the 24-month group. Complete data set analysis was carried out to include 107 (6-month group), 100 (12-month group) and 100 (24-month group) participants. Multiple imputation analyses were conducted where follow-up data was missing. The difference in the proportions of participants reporting a 'high' level of oral cleanliness at follow-up was significant (Chi-squared P = 0.003): 52.3% (6-month group), 47.0% (12-month group) and 30.0% (24-month group). Scale and polish was thought to be important by the majority in each group for keeping mouths clean and gums healthy, whitening teeth

  16. Modeling and Experimental Investigations of Mixing-Controlled Geochemical and Biological Reactions at the Pore Scale

    Science.gov (United States)

    Valocchi, A. J.; Werth, C. J.; Yoon, H.; Tang, Y.

    2012-12-01

    Several studies have demonstrated the important role played by mixing-controlled reactions in porous media. For example, transverse mixing of nutrients along the fringes of a contaminant plume is often the limiting step that controls overall degradation rate during natural or engineered in situ bioremediation. Similar mixing processes can promote precipitation/dissolution reactions during geological sequestration of carbon dioxide. Field and laboratory investigations have demonstrated that the length scale of transverse mixing zones can be very small, often on the order of centimeters or less. To study dispersion, mixing and reaction at this scale, we use pore-scale numerical simulation models and micro-fluidics laboratory experiments. An overview of our methods and findings, including comparisons between direct numerical simulations and laboratory experiments will be presented. The presentation will emphasize recent results including: (a) coupling of precipitation/dissolution with porosity reduction under different geochemical conditions, and (b) impact of pore structure on biodegradation and biofilm growth patterns. Our work has improved understanding of coupled flow, transport and reaction processes; however, there remain significant challenges in extending the results to larger field scales.

  17. Bias and precision in visual analogue scales: a randomized controlled trial.

    Science.gov (United States)

    Paul-Dauphin, A; Guillemin, F; Virion, J M; Briançon, S

    1999-11-15

    Various types of visual analogue scales (VAS) are used in epidemiologic and clinical research. This paper reports on a randomized controlled trial to investigate the effects of variations in the orientation and type of scale on bias and precision in cross-sectional and longitudinal analyses. This trial was included in the pilot study of the SU.VI.MAX (supplementation by antioxidant vitamins and minerals) prevention trial in France in 1994. Six types of VAS (simple, middle-marked, graphic rating, graduated, graduated-numbered, and numerical rating) and two orientations (horizontal and vertical) were used to measure three symptoms of ear, nose, and throat infection at 2-month intervals in 870 subjects. Differences between scales were analyzed by comparing variances (Levene's test) and means (variance-covariance analysis for repeated measures). Scale characteristics were shown to influence the proportion of zero and low values (i.e., there was a floor effect), but not mean scores. The precision of measurements varied cross-sectionally according to the type of scale, but no differences were observed in the precision of measurement of change over time. In conclusion, the characteristics of VAS seem to be important in cross-sectional studies, particularly when symptoms of low or high intensity are being measured. Researchers should try to reach a consensus on what type of VAS to use if studies are to be compared.

  18. Centers for Disease Control and Prevention (CDC) Radiation Hazard Scale Data Product Review Feedback Report

    Energy Technology Data Exchange (ETDEWEB)

    Askin, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Buddemeier, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alai, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Yu, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-20

    In support of the Department of Energy (DOE) National nuclear Security Administration (NNSA) and the Centers for Disease Control and Prevention (CDC), Lawrence Livermore National Laboratory (LLNL) assisted in the development of new data templates for disseminating and communicating FRMAC1 data products using the CDC Radiation Hazard Scale communication tool. To ensure these data products will be useful to stakeholders during a radiological emergency, LLNL facilitated opportunities for product socialization and review.

  19. Multi-agent based control of large-scale complex systems employing distributed dynamic inference engine

    Science.gov (United States)

    Zhang, Daili

    Increasing societal demand for automation has led to considerable efforts to control large-scale complex systems, especially in the area of autonomous intelligent control methods. The control system of a large-scale complex system needs to satisfy four system level requirements: robustness, flexibility, reusability, and scalability. Corresponding to the four system level requirements, there arise four major challenges. First, it is difficult to get accurate and complete information. Second, the system may be physically highly distributed. Third, the system evolves very quickly. Fourth, emergent global behaviors of the system can be caused by small disturbances at the component level. The Multi-Agent Based Control (MABC) method as an implementation of distributed intelligent control has been the focus of research since the 1970s, in an effort to solve the above-mentioned problems in controlling large-scale complex systems. However, to the author's best knowledge, all MABC systems for large-scale complex systems with significant uncertainties are problem-specific and thus difficult to extend to other domains or larger systems. This situation is partly due to the control architecture of multiple agents being determined by agent to agent coupling and interaction mechanisms. Therefore, the research objective of this dissertation is to develop a comprehensive, generalized framework for the control system design of general large-scale complex systems with significant uncertainties, with the focus on distributed control architecture design and distributed inference engine design. A Hybrid Multi-Agent Based Control (HyMABC) architecture is proposed by combining hierarchical control architecture and module control architecture with logical replication rings. First, it decomposes a complex system hierarchically; second, it combines the components in the same level as a module, and then designs common interfaces for all of the components in the same module; third, replications

  20. Event-triggered decentralized robust model predictive control for constrained large-scale interconnected systems

    Directory of Open Access Journals (Sweden)

    Ling Lu

    2016-12-01

    Full Text Available This paper considers the problem of event-triggered decentralized model predictive control (MPC for constrained large-scale linear systems subject to additive bounded disturbances. The constraint tightening method is utilized to formulate the MPC optimization problem. The local predictive control law for each subsystem is determined aperiodically by relevant triggering rule which allows a considerable reduction of the computational load. And then, the robust feasibility and closed-loop stability are proved and it is shown that every subsystem state will be driven into a robust invariant set. Finally, the effectiveness of the proposed approach is illustrated via numerical simulations.

  1. An enhanced hierarchical control strategy for the Internet of Things-based home scale microgrid

    DEFF Research Database (Denmark)

    Guan, Yajuan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2017-01-01

    As the intelligent control and detection technology improving, more and more smart devices/sensors can be used to increase the living standard. In order to integrate the Internet of Things (IoT) with microgrid (MG), an enhanced hierarchical control strategy for IoT-based home scale MG is proposed...... in this paper. Physical smart devices/sensors and inverters are defined at the primary level. Electrical and environmental variables deviation restoration loops are adopted at the secondary level. Power flow management and optimization algorithms with different objectives are deployed at the tertiary level...

  2. Full-scale wind tunnel investigation of a helicopter individual blade control system

    Science.gov (United States)

    Jacklin, Stephen A.; Leyland, Jane A.; Blaas, Achim

    1993-01-01

    This paper discusses the preparations and plans to test an individual rotor blade pitch control system in the 40- by 80- Foot Wind Tunnel at the NASA Ames Research Center. The test will be performed on a full-scale BO-105 rotor system using a control system made by Henschel Flugzeug-Werke, GmbH, Germany. The Individual Blade Control (IBC) actuators have been designed to replace the pitchlinks of the rotor system. The paper presents a brief historical perspective on the development of the individual blade control system and then describes the present IBC actuators and the wind tunnel test hardware. A discussion of the intended test matrix, expected potential benefits of IBC, and simulation results are included.

  3. Virtual reality distraction for pain control during periodontal scaling and root planing procedures.

    Science.gov (United States)

    Furman, Elena; Jasinevicius, T Roma; Bissada, Nabil F; Victoroff, Kristin Z; Skillicorn, Robert; Buchner, Marc

    2009-12-01

    Although pain management during periodontal treatment usually is achieved with anesthesia, alternative methods are available. The authors conducted a study to evaluate the analgesic effect of immersive virtual reality (VR) during periodontal scaling and root planing (SRP) procedures. The authors recruited 38 patients. They used a within-patient/split-mouth design. Patients received SRP under three treatment conditions in three quadrants. The three conditions were control, watching a movie and VR. After each SRP procedure, patients responded to questions about their discomfort and/or pain by using a visual analog scale (VAS) (range, 0 to 10 in which lower numbers indicate less pain or discomfort). The authors also recorded patients' blood pressure (BP) and pulse rate (PR). Patients were asked which of the three treatment modalities they preferred. The mean (+/- standard deviation) VAS scores for five questions pertaining to control, movie and VR were 3.95 +/- 2.1, 2.57 +/- 1.8 and 1.76 +/- 1.4, respectively. Paired t tests revealed that VAS scores were significantly lower during VR compared with the movie (P movie and control conditions. Patients reported that they preferred the VR condition. The results of this study suggest that use of immersive VR distraction may be an effective method of pain control during SRP procedures. Practitioners can use immersive VR distraction for pain control during SRP procedures.

  4. Large-Scale Advanced Prop-Fan (LAP) pitch change actuator and control design report

    Science.gov (United States)

    Schwartz, R. A.; Carvalho, P.; Cutler, M. J.

    1986-01-01

    In recent years, considerable attention has been directed toward improving aircraft fuel consumption. Studies have shown that the high inherent efficiency previously demonstrated by low speed turboprop propulsion systems may now be extended to today's higher speed aircraft if advanced high-speed propeller blades having thin airfoils and aerodynamic sweep are utilized. Hamilton Standard has designed a 9-foot diameter single-rotation Large-Scale Advanced Prop-Fan (LAP) which will be tested on a static test stand, in a high speed wind tunnel and on a research aircraft. The major objective of this testing is to establish the structural integrity of large-scale Prop-Fans of advanced construction in addition to the evaluation of aerodynamic performance and aeroacoustic design. This report describes the operation, design features and actual hardware of the (LAP) Prop-Fan pitch control system. The pitch control system which controls blade angle and propeller speed consists of two separate assemblies. The first is the control unit which provides the hydraulic supply, speed governing and feather function for the system. The second unit is the hydro-mechanical pitch change actuator which directly changes blade angle (pitch) as scheduled by the control.

  5. Validity and Reliability of the Brazilian Version of the Weight Control Behaviors Scale.

    Science.gov (United States)

    Dunker, Karin Louise Lenz; Claudino, Angelica Medeiros

    2017-10-01

    To develop and validate the weight-control behaviors (WCBs) scale and to evaluate its psychometric properties. We made use of data from a cluster-randomized trial assessing the effectiveness of the Brazilian New Moves Program. The Brazilian New Moves Program was a multicomponent intervention aimed at preventing weight-related problems among adolescent girls in public schools in São Paulo, Brazil. Healthy and unhealthy WCBs were strongly associated. A 2-factor solution was the best model to explain the correlation across items, including following constructs: (1) healthy WCB: exercising, eating more fruits and vegetables, drinking less regular soda or sweetened drinks, eating fewer sweets, and paying attention to portion sizes; and (2) unhealthy WCB: skipping meals and the presence of any other, combined unhealthy weight-control behaviors, including fasting, eating little, going on a diet, vomiting, taking diet pills, using diuretics (water pills), using laxatives, using food substitutes (powder/special drinks), and smoking more cigarettes. The WCB scale was determined to be reliable (internally consistent) and valid, with high scores positively associated with body dissatisfaction and high body mass index values. Individual reliability values were high for factors representing healthy and unhealthy WCBs. Our findings support the use of the WCB scale as a screening tool for overall weight control behaviors among female adolescents. This assessment tool should be considered in future observational and experimental prospective studies. Brazilian Registry of Clinical Trials: RBR-6ddpb3. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Adaptation of Self-Control and Self-Management Scale (SCMS) into Turkish Culture: A Study on Reliability and Validity

    Science.gov (United States)

    Ercoskun, Muhammet Hanifi

    2016-01-01

    The aim of this study is to adapt self-control and self-management scale (SCMS) developed by Mezo into Turkish and to test it considering gender and academic achievement variables. The scale was translated from English to Turkish for linguistic validity and then this scale was translated into English using back translation. The original and…

  7. Modelling and control of small-scale helicopter on a test platform

    Science.gov (United States)

    Lai, Gilbert M. Y.

    The helicopter is a Multiple-Input Multiple-Output (MIMO) system with highly coupled characteristics, which increases the complexity of the system dynamics. In addition, the system dynamics of the helicopter are unstable [1], referring to its tendency to deviate from an equilibrium when disturbed. Despite the complexity in its modelling and control, the benefit of using a helicopter for unmanned, autonomous applications can be tremendous. One particular application that motivates this research is the use of an unmanned small-scale helicopter in an autonomous survey mission over an area struck by disaster, such as an earthquake. The work presented in this thesis provides a framework for utilizing a platform system for research and development of small-scale helicopter systems. A platform system enables testing and analysis to be performed indoor in a controlled environment. This can provide a more convenient mean for helicopter research since the system is not affected by environmental elements, such as wind, rain or snow condition. However, the presence of the platform linkages poses challenges for analysis and controller design as it alters the helicopter system flight dynamics. Through a six degree-of-freedom (6 DOF) platform model derived in this research, the criteria for matching the trim conditions between the platform system and a stand alone helicopter have been identified. With the matched trim conditions, linearization is applied to perform analysis on the effects that the platform has on the system dynamics. The results of the analysis provide insights into both the limitations and benefits of utilizing the platform system for helicopter research. Finally, a Virtual Joint Control scheme is proposed as an unified control strategy for both the platform and the stand alone helicopter systems. Having a consistent control scheme between the two systems allows for comparisons between simulation and experimental results for the two systems to be made more

  8. Embedded Sensors and Controls to Improve Component Performance and Reliability -- Loop-scale Testbed Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kisner, Roger A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-01

    Embedded instrumentation and control systems that can operate in extreme environments are challenging to design and operate. Extreme environments limit the options for sensors and actuators and degrade their performance. Because sensors and actuators are necessary for feedback control, these limitations mean that designing embedded instrumentation and control systems for the challenging environments of nuclear reactors requires advanced technical solutions that are not available commercially. This report details the development of testbed that will be used for cross-cutting embedded instrumentation and control research for nuclear power applications. This research is funded by the Department of Energy's Nuclear Energy Enabling Technology program's Advanced Sensors and Instrumentation topic. The design goal of the loop-scale testbed is to build a low temperature pump that utilizes magnetic bearing that will be incorporated into a water loop to test control system performance and self-sensing techniques. Specifically, this testbed will be used to analyze control system performance in response to nonlinear and cross-coupling fluid effects between the shaft axes of motion, rotordynamics and gyroscopic effects, and impeller disturbances. This testbed will also be used to characterize the performance losses when using self-sensing position measurement techniques. Active magnetic bearings are a technology that can reduce failures and maintenance costs in nuclear power plants. They are particularly relevant to liquid salt reactors that operate at high temperatures (700 C). Pumps used in the extreme environment of liquid salt reactors provide many engineering challenges that can be overcome with magnetic bearings and their associated embedded instrumentation and control. This report will give details of the mechanical design and electromagnetic design of the loop-scale embedded instrumentation and control testbed.

  9. Validity of the Control Preferences Scale in patients with emotional disorders

    Directory of Open Access Journals (Sweden)

    De las Cuevas C

    2016-11-01

    Full Text Available Carlos De las Cuevas,1 Wenceslao Peñate2 1Department of Internal Medicine, Dermatology and Psychiatry, 2Department of Personality, Assessment and Psychological Treatments, University of La Laguna, San Cristóbal de La Laguna, Canary Islands, Spain Background: The Control Preferences Scale (CPS is the most frequently used measure of patients’ preferred roles in treatment decisions. The aim of this study was to provide data about the validity of CPS in psychiatric care of patients with emotional disorders. Methods: The original CPS was translated to Spanish using the process of cross-cultural adaptation of self-reported measures as the methodological model for Spanish translation. The final version was tested in a convenience sample of 621 consecutive psychiatric outpatients (461 depressive and 160 anxiety disorders that also completed the Shared Decision-Making Questionnaire, the Multidimensional Health Locus of Control Scale, the Drug Attitude Inventory, and a questionnaire including sociodemographic and clinical variables. Results: CPS showed a moderate internal consistency and a good convergent validity. Patients with collaborative and passive preferences expressed a greater reliance on psychotropics. Patients preferring a collaborative role self-reported greater perception of involvement in decision-making about their treatment. Patients preferring a passive role showed a greater external health locus of control. The most common preferred role was the collaborative–passive. Older patients and those under longer treatments preferred a passive role, while patients with higher levels of education preferred a collaborative role. Conclusion: The CPS is a valid measure of the amount of control that psychiatric outpatients with emotional disorders want to assume in the process of making decisions about their treatment. Keywords: Control Preferences Scale, psychiatric outpatients, emotional disorders, psychometric properties

  10. [Spanish version of the Multidimensional health locus of control scale innursing students].

    Science.gov (United States)

    Tomás-Sábado, Joaquín; Montes-Hidalgo, Javier

    2016-01-01

    To determine the preliminary psychometric properties of the Spanish form of the Multidimensional Health Locus of Control Scale (MHLC), which consists of three subscales: (1) Internalitu, (2) Powerful other externality, and (3) Chance externality. It also aims to study the relationship that the internal/external health control beliefs has with self-esteem, self-efficacy and perceived competence in a sample of nursing undergraduates. An observational and cross-sectional study including 109 nursing students who completed an anonymous questionnaire containing the demographic variables and the Spanish versions of the MHLC, the Rosenberg Self-Esteem Scale, the General Self-Efficacy Scale, and the Perceived personal competence Scale. A Cronbach's alpha coefficient of 0.713 for Internality, 0.665 for Chance and 0.728 for Powerful other were obtained. The test-retest correlation for the 18 items of the MHLC was 0.866. Internality subscale was positively and significantly correlated with self-efficacy and competence. By contrast, chance externality has negative and significant correlations with self-esteem and competence. There are no significant gender differences in any of the subscales. Younger subjects show greater tendency to external attribution. Factor analysis confirms the three-factor hypothesis. The results suggest that the Spanish form of the MHLC has adequate construct validity and acceptable metric properties. Also, they evidence the relationship between the attribution of health-related internal control with the perceived well-being and confidence in their own skills and abilities. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  11. POTENTIAL ENTOMOPATHOGENIC FUNGI TO CONTROL SCALE INSECT PEST ON CITRUS TANGERINE (CITRUS SUHUIENSIS TAN.

    Directory of Open Access Journals (Sweden)

    Triwiratno A.

    2017-12-01

    Full Text Available Achiving of food self-sufficiency can be done by using of local potential that is by agribusiness in Indonesia. One potential locally owned citrus agribusiness was the use of entomopathogenic fungi to improve the productivity of citrus. Reports showed decrease in productivity due to infestation of scale insect. The experiment was conducted at the Integrated Laboratory of Indonesian Citrus and Subtropical Fruit Research Institute in October 2013 to October 2014. The study began with a survey for scale insect infestation on citrus crops in high land, medium land and low in dry and rainy seasons. Taken from a collection of entomopathogenic fungi associated with scale insect in the field. Collection of fungi isolated from single conidia and its ability to infect selected scale insect. Entomopathogenic fungi were further tested for the viability and pathogenicity against scale insect. The results showed that the sclae insects attacked citrus were types of L.beckii and A.Aurantii. The highest attack occurred at low land during the dry season by L.beckii with population of 4.2 heads increased to 5.5 individuals per 10 cm in the rainy season. Viability test results showed that the isolates had viability above 50% were SKB4K, SKD1K and SBB3K for 73.6, 61.6 and 53% respectively, which were collected during the dry season. While isolates obtained in the rainy season were SBWD2H and SBWD3BH, each with aviability of 77.3 and 78.3% respectively. Pathogenicity test results showed that there were 6 isolates known to have potential as entomopathogenic fungi for controlling scale insect, namely, SBWB2H, SBWD2H, SBWD3BH, SKD1K, SBWD1K and SBB3K which had pathogenicity over 50% up to 14 days.

  12. Review and evaluation of literature on testing of chemical additives for scale control in geothermal fluids. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Crane, C.H.; Kenkeremath, D.C.

    1981-01-01

    A selected group of reported tests of chemical additives in actual geothermal fluids are reviewed and evaluated to summarize the status of chemical scale-control testing and identify information and testing needs. The task distinguishes between scale control in the cooling system of a flash plant and elsewhere in the utilization system due to the essentially different operating environments involved. Additives for non-cooling geothermal fluids are discussed by scale type: silica, carbonate, and sulfide.

  13. Interaural level difference-dependent gain control and synaptic scaling underlying binaural computation.

    Science.gov (United States)

    Xiong, Xiaorui R; Liang, Feixue; Li, Haifu; Mesik, Lukas; Zhang, Ke K; Polley, Daniel B; Tao, Huizhong W; Xiao, Zhongju; Zhang, Li I

    2013-08-21

    Binaural integration in the central nucleus of inferior colliculus (ICC) plays a critical role in sound localization. However, its arithmetic nature and underlying synaptic mechanisms remain unclear. Here, we showed in mouse ICC neurons that the contralateral dominance is created by a "push-pull"-like mechanism, with contralaterally dominant excitation and more bilaterally balanced inhibition. Importantly, binaural spiking response is generated apparently from an ipsilaterally mediated scaling of contralateral response, leaving frequency tuning unchanged. This scaling effect is attributed to a divisive attenuation of contralaterally evoked synaptic excitation onto ICC neurons with their inhibition largely unaffected. Thus, a gain control mediates the linear transformation from monaural to binaural spike responses. The gain value is modulated by interaural level difference (ILD) primarily through scaling excitation to different levels. The ILD-dependent synaptic scaling and gain adjustment allow ICC neurons to dynamically encode interaural sound localization cues while maintaining an invariant representation of other independent sound attributes. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Controlled Fabrication and High-Resolution Imaging of Molecular-Scale Three-Terminal Devices

    Science.gov (United States)

    Strachan, Douglas R.; Johnston, Danvers E.; Guiton, Beth S.; Park, T.-H.; Therien, M. J.; Davies, Peter K.; Bonnell, Dawn A.; Johnson, A. T. Charlie

    2007-03-01

    One of the biggest challenges to developing molecular-scale three terminal devices is to precisely fabricate and monitor the formation of the nanometer-scale electrodes (nanogaps). Recently, electromigrated nanogaps have been developed which provide sufficient gate-coupling to produce such devices. We have developed a technique for forming electromigrated nanogaps in a transmission electron microscope (TEM) in order to monitor their formation with high-resolution imaging in real time. The technique relies on computer-controlled electromigration using feedback to produce the nanogaps at room temperature. This TEM imaging allows us to monitor the dynamics of the device evolution, where the gaps remain ordered and clear of residue during the process. Using this technique, we find clear visual evidence for the importance of joule heating in the formation of electromigrated nanogaps. These electrodes can also be directly used in the construction of three terminal nanometer-scale devices. Our results have implications on the development of a wide range of novel molecular-scale devices. This work was supported by the National Science Foundation (NIRT Grant No. 0304531 and MRSEC award DMR05-20020).

  15. Anomalous Scaling from Controlled Closure in a Shell Model of Turbulence

    CERN Document Server

    Lvov, V S; Pomyalov, A; Procaccia, I; L'vov, Victor S.; Pierotti, Daniela; Pomyalov, Anna; Procaccia, Itamar

    1998-01-01

    We present a model of hydrodynamic turbulence for which the program of computing the scaling exponents from first principles can be developed in a controlled fashion. The model consists of $N$ suitably coupled copies of the "Sabra" shell model of turbulence. The couplings are chosen to include two components: random and deterministic, with a relative importance that is characterized by a parameter called $\\epsilon$. It is demonstrated, using numerical simulations of up to 25 copies and 28 shells that in the $N\\to functions whose scaling exponents are anomalous. The theoretical calculation of the scaling exponents follows verbatim the closure procedure suggested recently for the Navier-Stokes problem, with the additional advantage that in the $N\\to procedure. The main result of this paper is a finite and closed set of scale-invariant equations for the 2nd and 3rd order statistical objects of the theory. This set of equations takes into account terms up to order $\\epsilon^4$ and neglects terms of order $\\epsilo...

  16. Complexity in earthquake sequences controlled by multi-scale heterogeneity in fault fracture energy

    Science.gov (United States)

    Aochi, H.; Ide, S.

    2008-12-01

    A series of dynamic rupture events under constant tectonic loading is simulated on a fault with multi-scale heterogeneity and a stochastic rupture initiation process. The fracture energy of the fault plane is assumed to have multi-scale heterogeneous distribution using fractal circular patches. The stochastic rupture initiation process with a function of the accumulated stress is introduced in order to take account for unknown smaller- scale heterogeneity and incertitude. Five realizations of a statistical spatial distribution of fracture energy (fault heterogeneity maps) are tested for the simulations of earthquake sequences during a few seismic cycles. The diversity of earthquake sequences is principally controlled by the spatial distribution of the patches. The effect of dynamic rupture appears in the residual stress after the characteristic events due to their directivity and this localizes the subsequent sequences. Although the characteristic earthquakes occur rather regularly in time and similarly in different seismic cycles, some irregular behaviors are found, based on the heterogeneity maps and the randomness of the preceding earthquake sequence, leading to a visible anomaly in the seismicity. Such anomaly is not predicable, but understandable through the analysis of the concerned earthquakes during the cycle. The similarity and the diversity simulated in this study, governed by the structure of an inherent distribution of multi-scale heterogeneity, suggests the importance of pre-existing heterogeneity field along the fault for the appearance of earthquake sequences, including those that are characteristic.

  17. Characteristic time scales of electroencephalograms of narcoleptic patients and healthy controls.

    Science.gov (United States)

    Kim, Jong Won; Shin, Hongbeom; Kim, Eui-Joong; Koo, Young-Jin; Choi, Byunghun; Park, Kwang Suk; Jeong, Do-Un

    2010-10-01

    Sleep electroencephalograms (EEGs) typically showed correlated fluctuations that became random-like oscillations beyond a characteristic time scale. To investigate this behavior quantitatively, the detrended fluctuation analysis (DFA) was applied to EEGs of 10 narcoleptic patients (22.0 ± 4.0 yrs; 6 males) and 8 healthy controls (24.0 ± 2.0 yrs; 5 males). The characteristic time scales of the narcoleptics and controls were estimated as 1.8 ± 0.7 and 4.4 ± 1.2s, respectively (significance level, pDFA of the EEGs segmented into 30s epochs and found that the DFA scaling exponents increased in deep sleep stages. These results were verified with power spectrum and auto-correlation analysis, and reproduced by a mathematical model. We thus concluded that characteristics of EEGs of narcoleptic patients could be differentiated from those of healthy subjects, suggesting a potential application of DFA in diagnosing narcolepsy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Large-scale control strategy for drag reduction in turbulent channel flows

    Science.gov (United States)

    Yao, Jie; Chen, Xi; Thomas, Flint; Hussain, Fazle

    2017-06-01

    In a recent article, Canton et al. [J. Canton et al., Phys. Rev. Fluids 1, 081501(R) (2016), 10.1103/PhysRevFluids.1.081501] reported significant drag reduction in turbulent channel flow by using large-scale, near-wall streamwise swirls following the control strategy of Schoppa and Hussain [W. Schoppa and F. Hussain, Phys. Fluids 10, 1049 (1998), 10.1063/1.869789] for low Reynolds numbers only, but found no drag reduction at high friction Reynolds numbers (Reτ=550 ). Here we show that the lack of drag reduction at high Re observed by Canton et al. is remedied by the proper choice of the large-scale control flow. In this study, we apply near-wall opposed wall-jet forcing to achieve drag reduction at the same (high) Reynolds number where Canton et al. found no drag reduction. The steady excitation is characterized by three control parameters, namely, the wall-jet-forcing amplitude A+, the spanwise spacing Λ+, and the wall jet height yc+ (+ indicates viscous scaling); the primary difference between Schoppa and Hussain's work (also that of Canton et al.) and this Rapid Communication is the emphasis on the explicit choice of yc+ here. We show as an example that with a choice of A+≈0.015 ,Λ+≈1200 , and yc+≈30 the flow control definitely suppresses the wall shear stress at a series of Reynolds numbers, namely, 19 %,14 % , and 12 % drag reductions at Reτ=180 , 395, and 550, respectively. Further study should explore optimization of these parameter values.

  19. Advanced Grid-Friendly Controls Demonstration Project for Utility-Scale PV Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, Vahan; O' Neill, Barbara

    2016-01-21

    A typical photovoltaic (PV) power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. The availability and dissemination of actual test data showing the viability of advanced utility-scale PV controls among all industry stakeholders can leverage PV's value from being simply an energy resource to providing additional ancillary services that range from variability smoothing and frequency regulation to power quality. Strategically partnering with a selected utility and/or PV power plant operator is a key condition for a successful demonstration project. The U.S. Department of Energy's (DOE's) Solar Energy Technologies Office selected the National Renewable Energy Laboratory (NREL) to be a principal investigator in a two-year project with goals to (1) identify a potential partner(s), (2) develop a detailed scope of work and test plan for a field project to demonstrate the gird-friendly capabilities of utility-scale PV power plants, (3) facilitate conducting actual demonstration tests, and (4) disseminate test results among industry stakeholders via a joint NREL/DOE publication and participation in relevant technical conferences. The project implementation took place in FY 2014 and FY 2015. In FY14, NREL established collaborations with AES and First Solar Electric, LLC, to conduct demonstration testing on their utility-scale PV power plants in Puerto Rico and Texas, respectively, and developed test plans for each partner. Both Puerto Rico Electric Power Authority and the Electric Reliability Council of Texas expressed interest in this project because of the importance of such advanced controls for the reliable operation of their power systems under high penetration levels of variable renewable generation. During FY15, testing was completed on both plants, and a large amount of test data was produced and analyzed that demonstrates the ability of

  20. Optimal control strategy for a novel computer virus propagation model on scale-free networks

    Science.gov (United States)

    Zhang, Chunming; Huang, Haitao

    2016-06-01

    This paper aims to study the combined impact of reinstalling system and network topology on the spread of computer viruses over the Internet. Based on scale-free network, this paper proposes a novel computer viruses propagation model-SLBOSmodel. A systematic analysis of this new model shows that the virus-free equilibrium is globally asymptotically stable when its spreading threshold is less than one; nevertheless, it is proved that the viral equilibrium is permanent if the spreading threshold is greater than one. Then, the impacts of different model parameters on spreading threshold are analyzed. Next, an optimally controlled SLBOS epidemic model on complex networks is also studied. We prove that there is an optimal control existing for the control problem. Some numerical simulations are finally given to illustrate the main results.

  1. Control of modular multilevel converters for grid integration of full-scale wind energy conversion systems

    Science.gov (United States)

    Debnath, Suman

    The growing demand for wind power generation has pushed the capacity of wind turbines towards MW power levels. Higher capacity of the wind turbines necessitates operation of the generators and power electronic conversion systems at higher voltage/power levels. The power electronic conversion system of a wind energy conversion system (WECS) needs to meet the stringent requirements in terms of reliability, efficiency, scalability and ease of maintenance, power quality, and dv/dt stress on the generator/transformer. Although the multilevel converters including the neutral point clamped (NPC) converter and the active NPC converter meet most of the requirements, they fall short in reliability and scalability. Motivated by modularity/scalability feature of the modular multilevel converter (MMC), this research is to enable the MMC to meet all of the stringent requirements of the WECS by addressing their unique control challenges. This research presents systematic modeling and control of the MMC to enable it to be a potential converter topology for grid integration of full-scale WECSs. Based on the developed models, appropriate control systems for control of circulating current and capacitor voltages under fixed- and variable-frequency operations are proposed. Using the developed MMC models, a gradient-based cosimulation algorithm to optimize the gains of the developed control systems, is proposed. Performance/effectiveness of the developed models and the proposed control systems for the back-to-back MMC-based WECS are evaluated/verified based on simulations studies in the PSCAD/EMTDC software environment and experimental case studies on a laboratory-scale hardware prototype.

  2. Controllable Grid Interface for Testing Ancillary Service Controls and Fault Performance of Utility-Scale Wind Power Generation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, Vahan; Koralewicz, Przemyslaw; Wallen, Robb; Muljadi, Eduard

    2017-02-01

    The rapid expansion of wind power has led many transmission system operators to demand modern wind power plants to comply with strict interconnection requirements. Such requirements involve various aspects of wind power plant operation, including fault ride-through and power quality performance as well as the provision of ancillary services to enhance grid reliability. During recent years, the National Renewable Energy Laboratory (NREL) of the U.S. Department of Energy has developed a new, groundbreaking testing apparatus and methodology to test and demonstrate many existing and future advanced controls for wind generation (and other renewable generation technologies) on the multimegawatt scale and medium-voltage levels. This paper describes the capabilities and control features of NREL's 7-MVA power electronic grid simulator (also called a controllable grid interface, or CGI) that enables testing many active and reactive power control features of modern wind turbine generators -- including inertial response, primary and secondary frequency responses, and voltage regulation -- under a controlled, medium-voltage grid environment. In particular, this paper focuses on the specifics of testing the balanced and unbalanced fault ride-through characteristics of wind turbine generators under simulated strong and weak medium-voltage grid conditions. In addition, this paper provides insights on the power hardware-in-the-loop feature implemented in the CGI to emulate (in real time) the conditions that might exist in various types of electric power systems under normal operations and/or contingency scenarios. Using actual test examples and simulation results, this paper describes the value of CGI as an ultimate modeling validation tool for all types of 'grid-friendly' controls by wind generation.

  3. Large-scale control site selection for population monitoring: an example assessing Sage-grouse trends

    Science.gov (United States)

    Fedy, Bradley C.; O'Donnell, Michael; Bowen, Zachary H.

    2015-01-01

    Human impacts on wildlife populations are widespread and prolific and understanding wildlife responses to human impacts is a fundamental component of wildlife management. The first step to understanding wildlife responses is the documentation of changes in wildlife population parameters, such as population size. Meaningful assessment of population changes in potentially impacted sites requires the establishment of monitoring at similar, nonimpacted, control sites. However, it is often difficult to identify appropriate control sites in wildlife populations. We demonstrated use of Geographic Information System (GIS) data across large spatial scales to select biologically relevant control sites for population monitoring. Greater sage-grouse (Centrocercus urophasianus; hearafter, sage-grouse) are negatively affected by energy development, and monitoring of sage-grouse population within energy development areas is necessary to detect population-level responses. Weused population data (1995–2012) from an energy development area in Wyoming, USA, the Atlantic Rim Project Area (ARPA), and GIS data to identify control sites that were not impacted by energy development for population monitoring. Control sites were surrounded by similar habitat and were within similar climate areas to the ARPA. We developed nonlinear trend models for both the ARPA and control sites and compared long-term trends from the 2 areas. We found little difference between the ARPA and control sites trends over time. This research demonstrated an approach for control site selection across large landscapes and can be used as a template for similar impact-monitoring studies. It is important to note that identification of changes in population parameters between control and treatment sites is only the first step in understanding the mechanisms that underlie those changes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  4. Biotic and abiotic controls of argentine ant invasion success at local and landscape scales

    Science.gov (United States)

    Menke, S.B.; Fisher, R.N.; Jetz, W.; Holway, D.A.

    2007-01-01

    Although the ecological success of introduced species hinges on biotic interactions and physical conditions, few experimental studies - especially on animals - have simultaneously investigated the relative importance of both types of factors. The lack of such research may stem from the common assumption that native and introduced species exhibit similar environmental tolerances. Here we combine experimental and spatial modeling approaches (1) to determine the relative importance of biotic and abiotic controls of Argentine ant (Linepithema humile) invasion success, (2) to examine how the importance of these factors changes with spatial scale in southern California (USA), and (3) to assess how Argentine ants differ from native ants in their environmental tolerances. A factorial field experiment that combined native ant removal with irrigation revealed that Argentine ants failed to invade any dry plots (even those lacking native ants) but readily invaded all moist plots. Native ants slowed the spread of Argentine ants into irrigated plots but did not prevent invasion. In areas without Argentine ants, native ant species showed variable responses to irrigation. At the landscape scale, Argentine ant occurrence was positively correlated with minimum winter temperature (but not precipitation), whereas native ant diversity increased with precipitation and was negatively correlated with minimum winter temperature. These results are of interest for several reasons. First, they demonstrate that fine-scale differences in the physical environment can eclipse biotic resistance from native competitors in determining community susceptibility to invasion. Second, our results illustrate surprising complexities with respect to how the abiotic factors limiting invasion can change with spatial scale, and third, how native and invasive species can differ in their responses to the physical environment. Idiosyncratic and scale-dependent processes complicate attempts to forecast where

  5. The Design and Scale-Up of Multiple-Impeller Fermenters for Liquid Film Controlled Processes

    Directory of Open Access Journals (Sweden)

    Labík, L.

    2013-05-01

    Full Text Available Mechanically agitated gas-liquid contactors are frequently used in the chemical, food and biochemical industries as fermenters and as hydrogenation or chlorination reactors. However wide is the usage of such vessels, their design is not based on chemical engineering data, but is still rather empirical. Thus, it is highly desirable to have a tool for the rational design of agitated gas-liquid contactors that is based on fundamental chemical engineering parameters that are transferable to other systems and operating conditions. Focusing on liquid film-controlled processes and using the data from fermenters of different scales, we develop kLa correlations that are suitable for scale-up. First, we discuss how to determine the proper experimental kLa values, which are not distorted by other equipment parameters as is the gas residence time. We demonstrate the possible kLa distortion on the pilot-plant experimental data by comparing the results obtained by two different experimental techniques. Further, we present physically correct kLa data for fully non-coalescent (sodium sulphate solution batch. The data are presented both for laboratory and pilot-plant fermenters. We identify the process parameters, the values of which are dependent on the vessel scale when operated under the same power input per volume, and, using these parameters, we develop common kLa correlations suitable to describe the data for various scales of the vessel. The correlations developed reduce the uncertainty in predicting the volume of industrial scale fermenters from almost 1/2 to 1/4 of their total volume, thereby enabling significant reductions in both the initial costs, and operating costs.

  6. A multitask sliding mode control for mismatched uncertain large-scale systems

    Science.gov (United States)

    Tsai, Yao-Wen; Van Huynh, Van

    2015-09-01

    A new sliding mode control (SMC) approach, output variables only, single phase only and chattering phenomenon free, is presented for a class of mismatched uncertain large-scale systems. For a new multitask SMC, it is not required that the system states are available. Moreover, the sliding function in this study just depends on output variables. Using an exponential type sliding surface, the system states are always in the sliding mode at the beginning time t = 0. Using a newly appropriate linear matrix inequality stability conditions by the Lyapunov method are derived such that each subsystem in the new sliding mode is completely invariant to matched uncertainties. As a result, robustness of the mismatched uncertain large-scale systems can be assured throughout an entire response of the system starting from the initial time t = 0. In every subsystem, a scheme of decentralised control using only output states is proposed. In addition, a continuous controller is finally designed for chattering removal. Finally, a numerical example is used to demonstrate the efficacy of the proposed method.

  7. Control Algorithms for Large-scale Single-axis Photovoltaic Trackers

    Directory of Open Access Journals (Sweden)

    Dorian Schneider

    2012-01-01

    Full Text Available The electrical yield of large-scale photovoltaic power plants can be greatly improved by employing solar trackers. While fixed-tilt superstructures are stationary and immobile, trackers move the PV-module plane in order to optimize its alignment to the sun. This paper introduces control algorithms for single-axis trackers (SAT, including a discussion for optimal alignment and backtracking. The results are used to simulate and compare the electrical yield of fixed-tilt and SAT systems. The proposed algorithms have been field tested, and are in operation in solar parks worldwide.

  8. Status of the Use of Large-Scale Corba-Distributed Software Framework for NIF Controls

    Energy Technology Data Exchange (ETDEWEB)

    Carey, R W; Bettenhausen, R C; Estes, C M; Fisher, J M; Krammen, J E; Lagin, L J; Ludwigsen, A P; Mathisen, D G; Matone, J T; Patterson, R W; Reynolds, C A; Sanchez, R J; Stout, E A; Tappero, J D; Van Arsdall, P J

    2005-09-09

    The Integrated Computer Control System (ICCS) for the National Ignition Facility (NIF) is based on a scalable software framework that will be distributed over some 750 Computers throughout the NIF. The framework provides templates and services at multiple levels of abstraction for the construction of software applications that communicate via CORBA (Common Object Request Broker Architecture). Object-oriented software design patterns are implemented as templates to be extended by application software. Developers extend the framework base classes to model the numerous physical control points. About 140 thousand software objects, each individually addressable through CORBA, will be active at full scale. Most of the objects have persistent state that is initialized at system start-up and stored in a database. Centralized server programs that implement events, alerts, reservations, message logging, data archive, name services, and process management provide additional framework services. A higher-level model-based, distributed shot automation framework also provides a flexible and scalable scripted framework for automatic sequencing of work-flow for control and monitoring of NIF shots. The ICCS software framework has allowed for efficient construction of a software system that supports a large number of distributed control points representing a complex control application. Status of the use of this framework during first experimental shot campaigns and initial commissioning and build-out of the laser facility is described.

  9. Multi-Time Scale Control of Demand Flexibility in Smart Distribution Networks

    Directory of Open Access Journals (Sweden)

    Bishnu P. Bhattarai

    2017-01-01

    Full Text Available This paper presents a multi-timescale control strategy to deploy electric vehicle (EV demand flexibility for simultaneously providing power balancing, grid congestion management, and economic benefits to participating actors. First, an EV charging problem is investigated from consumer, aggregator, and distribution system operator’s perspectives. A hierarchical control architecture (HCA comprising scheduling, coordinative, and adaptive layers is then designed to realize their coordinative goal. This is realized by integrating multi-time scale controls that work from a day-ahead scheduling up to real-time adaptive control. The performance of the developed method is investigated with high EV penetration in a typical residential distribution grid. The simulation results demonstrate that HCA efficiently utilizes demand flexibility stemming from EVs to solve grid unbalancing and congestions with simultaneous maximization of economic benefits to the participating actors. This is ensured by enabling EV participation in day-ahead, balancing, and regulation markets. For the given network configuration and pricing structure, HCA ensures the EV owners to get paid up to five times the cost they were paying without control.

  10. A versatile and light-weight slow control system for small-scale applications

    Science.gov (United States)

    Zappa, P.; Bütikofer, L.; Coderre, D.; Kaminsky, B.; Schumann, M.; von Sivers, M.

    2016-09-01

    We present an open source slow control system for small and medium scale projects. Thanks to its modular and flexible design, where the various instruments are read and controlled by independent plugins, Doberman (Detector OBsERving and Monitoring ApplicatioN) can be quickly adapted for many applications, also making use of existing code or proprietary components. The system uses a SQL database to store the data from the instruments and provides an online application to display and browse through the data. It allows the modification of device settings while the program is running and features a protocol to handle exceptions, including the automated distribution of alarm messages. We present two case studies from astroparticle physics, on which Doberman is successfully deployed: a low-background screening facility installed in a remote underground laboratory and a detector R&D platform using cryogenic liquid xenon.

  11. WAMS Based Intelligent Operation and Control of Modern Power System with large Scale Renewable Energy Penetration

    DEFF Research Database (Denmark)

    Rather, Zakir Hussain

    Electricity demand worldwide is growing which is mainly driven by growing industrial activities and the widening of access to consumers in the developing world. On the other hand, limitations of conventional sources of energy generation coupled with substantial financial and regulatory incentives...... of complex power systems. WAMS is rapidly being implemented in power systems across the globe and is seen a means to realize smart grid at transmission system level. This thesis (industrial PhD with kk-electronic) proposes WAMS based methods to intelligently control and operate large scale wind integrated...... power system with least dependence on conventional power plants. An important aspect of WAMS realization in a power system is optimal placement of expensive PMUs in order to realize cost effective and reliable grid state monitoring and control. Coupled with Real time digital simulator (RTDS) based...

  12. Integrating Systems Health Management with Adaptive Controls for a Utility-Scale Wind Turbine

    Science.gov (United States)

    Frost, Susan A.; Goebel, Kai; Trinh, Khanh V.; Balas, Mark J.; Frost, Alan M.

    2011-01-01

    Increasing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. Systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage. Advanced adaptive controls can provide the mechanism to enable optimized operations that also provide the enabling technology for Systems Health Management goals. The work reported herein explores the integration of condition monitoring of wind turbine blades with contingency management and adaptive controls. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

  13. Linkage disequilibrium-based quality control for large-scale genetic studies.

    Directory of Open Access Journals (Sweden)

    Paul Scheet

    2008-08-01

    Full Text Available Quality control (QC is a critical step in large-scale studies of genetic variation. While, on average, high-throughput single nucleotide polymorphism (SNP genotyping assays are now very accurate, the errors that remain tend to cluster into a small percentage of "problem" SNPs, which exhibit unusually high error rates. Because most large-scale studies of genetic variation are searching for phenomena that are rare (e.g., SNPs associated with a phenotype, even this small percentage of problem SNPs can cause important practical problems. Here we describe and illustrate how patterns of linkage disequilibrium (LD can be used to improve QC in large-scale, population-based studies. This approach has the advantage over existing filters (e.g., HWE or call rate that it can actually reduce genotyping error rates by automatically correcting some genotyping errors. Applying this LD-based QC procedure to data from The International HapMap Project, we identify over 1,500 SNPs that likely have high error rates in the CHB and JPT samples and estimate corrected genotypes. Our method is implemented in the software package fastPHASE, available from the Stephens Lab website (http://stephenslab.uchicago.edu/software.html.

  14. The Development and Validation of the Indian Family Violence and Control Scale.

    Directory of Open Access Journals (Sweden)

    Ameeta S Kalokhe

    Full Text Available The high prevalence of domestic violence (DV among married women in India and associated negative health repercussions highlight the need for effective prevention strategies and tools to measure the efficacy of such interventions. Literature supporting differing manifestations of DV by culture underscores the need for a culturally-tailored scale to more effectively measure DV in the Indian context. We therefore aimed to develop and validate such a tool, the Indian Family Violence and Control Scale (IFVCS, through a mixed-methods study. The psychometric development of IFVCS is herein discussed. After field pre-testing and expert review, a 63-item questionnaire was administered to a random sample of 630 married women from May-July 2013 in Pune, India. The item response theory approach for binary data to explore the IFVCS structure suggested that IFVCS is reliable, with the majority of items having high (>0.5 and significant factor loadings. Concurrent validity, assessed by comparing responses to IFVCS with the validated, abridged Conflict Tactics Scale-2, was high (r = 0.899, p<0.001 as was the construct validity, demonstrated by its significant association with several established DV correlates. Therefore, initial assessment of the IFVCS psychometric properties suggests that it is an effective tool for measuring DV among married women in India and speaks to its capacity for enhancing understanding of DV epidemiology and for evaluating the effectiveness of future DV interventions.

  15. Application Of GIS Software For Erosion Control In The Watershed Scale

    Directory of Open Access Journals (Sweden)

    C. Setyawan

    2017-01-01

    Full Text Available Land degradation in form of soil erosion due to uncontrolled farming is occurred in many watersheds of Indonesia particularly in Java Island. Soil erosion is decreasing watershed function as a rainwater harvesting area. Good conservation practices need to be applied to prevent more degradation. This study aims to investigate the effectiveness of land conservation practice for erosion control through land use modeling in the watershed scale. The modeling was applied in the Sempor watershed Indonesia. Three scenarios of land use were used for modeling. Soil erosion measurement and land use modeling were performed by using Universal Soil Loss Equation USLE method and Geographic Information System GIS software ArcGIS 10.1. Land use modeling was conducted by increasing permanent vegetation coverage from existing condition 4 to 10 20 and 30. The result showed that the modeling can reduce heavy class erosion about 15-37 of total area. GIS provides a good tool for erosion control modeling in the watershed scale.

  16. Psychometric properties of the Danish versions of headache-specific locus of control scale and headache management self-efficacy scale

    DEFF Research Database (Denmark)

    Hansen, Jacob Sander; Bendtsen, Lars; Jensen, Rigmor

    2009-01-01

    The purpose of the study is to test the cross-cultural adaptation and psychometric properties of a Danish version of the Headache-Specific Locus of Control Scale (HSLC) and the Headache Management Self-Efficacy Scale (HMSE) in a tertiary headache centre. HSLC and HMSE are headache-specific measures...... of locus of control (LOC) and SE. The Danish versions of the HSLC and the HMSE were created according to the guidelines for cross-cultural adaptation of self-report measures. The HSLC and HMSE were administered to 135 consecutively referred headache patients in a tertiary headache centre together....... The results are consistent with the earlier findings of the original American versions of HMSE and HSLC. These scales seem to be valid and valuable tools for testing of psychological aspects related to level of functioning and quality of life for headache patients across different cultures of Western society...

  17. Multi-scale Control and Enhancement of Reactor Boiling Heat Flux by Reagents and Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Manglik, R M; Athavale, A; Kalaikadal, D S; Deodhar, A; Verma, U

    2011-09-02

    The phenomenological characterization of the use of non-invasive and passive techniques to enhance the boiling heat transfer in water has been carried out in this extended study. It provides fundamental enhanced heat transfer data for nucleate boiling and discusses the associated physics with the aim of addressing future and next-generation reactor thermal-hydraulic management. It essentially addresses the hypothesis that in phase-change processes during boiling, the primary mechanisms can be related to the liquid-vapor interfacial tension and surface wetting at the solidliquid interface. These interfacial characteristics can be significantly altered and decoupled by introducing small quantities of additives in water, such as surface-active polymers, surfactants, and nanoparticles. The changes are fundamentally caused at a molecular-scale by the relative bulk molecular dynamics and adsorption-desorption of the additive at the liquid-vapor interface, and its physisorption and electrokinetics at the liquid-solid interface. At the micro-scale, the transient transport mechanisms at the solid-liquid-vapor interface during nucleation and bubblegrowth can be attributed to thin-film spreading, surface-micro-cavity activation, and micro-layer evaporation. Furthermore at the macro-scale, the heat transport is in turn governed by the bubble growth and distribution, macro-layer heat transfer, bubble dynamics (bubble coalescence, collapse, break-up, and translation), and liquid rheology. Some of these behaviors and processes are measured and characterized in this study, the outcomes of which advance the concomitant fundamental physics, as well as provide insights for developing control strategies for the molecular-scale manipulation of interfacial tension and surface wetting in boiling by means of polymeric reagents, surfactants, and other soluble surface-active additives.

  18. Field Scale Spatial Modelling of Surface Soil Quality Attributes in Controlled Traffic Farming

    Science.gov (United States)

    Guenette, Kris; Hernandez-Ramirez, Guillermo

    2017-04-01

    The employment of controlled traffic farming (CTF) can yield improvements to soil quality attributes through the confinement of equipment traffic to tramlines with the field. There is a need to quantify and explain the spatial heterogeneity of soil quality attributes affected by CTF to further improve our understanding and modelling ability of field scale soil dynamics. Soil properties such as available nitrogen (AN), pH, soil total nitrogen (STN), soil organic carbon (SOC), bulk density, macroporosity, soil quality S-Index, plant available water capacity (PAWC) and unsaturated hydraulic conductivity (Km) were analysed and compared among trafficked and un-trafficked areas. We contrasted standard geostatistical methods such as ordinary kriging (OK) and covariate kriging (COK) as well as the hybrid method of regression kriging (ROK) to predict the spatial distribution of soil properties across two annual cropland sites actively employing CTF in Alberta, Canada. Field scale variability was quantified more accurately through the inclusion of covariates; however, the use of ROK was shown to improve model accuracy despite the regression model composition limiting the robustness of the ROK method. The exclusion of traffic from the un-trafficked areas displayed significant improvements to bulk density, macroporosity and Km while subsequently enhancing AN, STN and SOC. The ability of the regression models and the ROK method to account for spatial trends led to the highest goodness-of-fit and lowest error achieved for the soil physical properties, as the rigid traffic regime of CTF altered their spatial distribution at the field scale. Conversely, the COK method produced the most optimal predictions for the soil nutrient properties and Km. The use of terrain covariates derived from light ranging and detection (LiDAR), such as of elevation and topographic position index (TPI), yielded the best models in the COK method at the field scale.

  19. Hydrologic control on the root growth of Salix cuttings at the laboratory scale

    Science.gov (United States)

    Bau', Valentina; Calliari, Baptiste; Perona, Paolo

    2017-04-01

    Riparian plant roots contribute to the ecosystem functioning and, to a certain extent, also directly affect fluvial morphodynamics, e.g. by influencing sediment transport via mechanical stabilization and trapping. There is much both scientific and engineering interest in understanding the complex interactions among riparian vegetation and river processes. For example, to investigate plant resilience to uprooting by flow, one should quantify the probability that riparian plants may be uprooted during specific flooding event. Laboratory flume experiments are of some help to this regard, but are often limited to use grass (e.g., Avena and Medicago sativa) as vegetation replicate with a number of limitations due to fundamental scaling problems. Hence, the use of small-scale real plants grown undisturbed in the actual sediment and within a reasonable time frame would be particularly helpful to obtain more realistic flume experiments. The aim of this work is to develop and tune an experimental technique to control the growth of the root vertical density distribution of small-scale Salix cuttings of different sizes and lengths. This is obtained by controlling the position of the saturated water table in the sedimentary bed according to the sediment size distribution and the cutting length. Measurements in the rhizosphere are performed by scanning and analysing the whole below-ground biomass by means of the root analysis software WinRhizo, from which root morphology statistics and the empirical vertical density distribution are obtained. The model of Tron et al. (2015) for the vertical density distribution of the below-ground biomass is used to show that experimental conditions that allow to develop the desired root density distribution can be fairly well predicted. This augments enormously the flexibility and the applicability of the proposed methodology in view of using such plants for novel flow erosion experiments. Tron, S., Perona, P., Gorla, L., Schwarz, M., Laio, F

  20. Personality profiles between obese and control subjects assessed with five standardized personality scales.

    Science.gov (United States)

    López-Pantoja, José L; Cabranes, José A; Sanchez-Quintero, Sabrina; Velao, Manuel; Sanz, Montserrat; Torres-Pardo, Beatriz; Ancín, Inés; Cabrerizo, Lucio; Rubio, Miguel A; Lopez-Ibor, Juan J; Barabash, Ana

    2012-01-01

    Psychopathology may exert influence on developing and maintaining obesity. Studies of personality traits or psychopathology of personality in obesity are scarce and contradictory. The aim of this study was to compare personality profiles between obese and normal-weight subjects and to determine the most useful tool to detect differences, considering that psychological assessment and psychotherapeutical support should be included within the overall management of these patients.* We examined 55 obese subjects (mean BMI=43kg/ m2) and 66 controls (mean BMI =21.7kg/m2). We used the personality assessment tools: MCMI-II, TCI-R, EPQ-A, BIS-111 and SSS. Factorial multivariate analysis of variance was applied; with factors BMI, Gender and Age as a covariate. Significant differences between groups were more marked in the clinical syndrome scales of MCMI-II, particularly in Major-Depression, Thought-Disorder, Anxiety, Somatoform and Alcohol-Dependence. Among obese, women scored higher than men in all scales but not significantly. We have found significant differences in normal personality dimensions between both groups in TCI-R. Obese showed higher scores in Harm Avoidance, and lower in Novelty Seeking, Persistence and Self-transcendence. The remaining tests have not been useful for differentiating personality traits between both groups. Obese subjects showed different personality profiles than control subjects. The most useful scales for determining these differences might be those designed to assess pathological personality such as MCMI-II. Less important would be those intended to measure normal personality traits, such as TCI-R and EPQ-A.

  1. PedsQL gastrointestinal symptoms scales and gastrointestinal worry scales in pediatric patients with functional and organic gastrointestinal diseases in comparison to healthy controls

    Science.gov (United States)

    The primary objective was to compare the gastrointestinal (GI) symptoms and worry of pediatric patients with functional GI disorders (FGIDs) and organic GI diseases to healthy controls utilizing the Pediatric Quality of Life Inventory (PedsQL) Gastrointestinal Symptoms and Worry Scales for patient s...

  2. Factors controlling gully erosion at different spatial and temporal scales in rangelands of SW Spain

    Science.gov (United States)

    Gómez Gutiérrez, Á.; Schnabel, S.; Lavado Contador, J. F.; Pulido Fernández, M.

    2009-04-01

    Mediterranean climate with Atlantic influences. Results showed that at the catchment scale, and for a short period (1-10 years), rainfall and soil moisture were the most important factors controlling gully erosion rates. In fact, gully erosion was highly related with the rainfall amount (r=0,90), with the number of times event discharge exceeded 1000 cubic meters (r=0,76) and with the number of times peak discharge exceeded 100 l/s (r=0,72). However, when the temporal scale was extended to several decades (from 1945 to 2006), land use and vegetation cover (specially the extension of cultivated area and livestock density) proved to be the most important factors determining the area affected by gullying. With respect to the spatial variation of gullying at the regional scale, the model results indicate lithology as being the most important variable, followed by vegetation structure and summer rainfall. This model was able to explain a large portion of the spatial distribution of gullies at the regional scale. Concluding, at different spatial and temporal scales the importance of factors which determine gully erosion intensity, extension and rates varies notably. At the short-term rainfall and runoff dynamics and the moisture content of the sediments are the dominant factors, whereas at the medium-term land use and vegetation cover become more important. At the regional scale lithology and vegetation turned out to be the dominant factors in determining the location of areas susceptible to gully erosion in rangelands of Extremadura.

  3. Localized Power Control for Multihop Large-Scale Internet of Things

    KAUST Repository

    Bader, Ahmed

    2015-08-04

    In this paper, we promote the use of multihop networking in the context of large-scale Internet of Things (IoT). Recognizing concerns related to the scalability of classical multihop routing and medium access techniques, we advocate the use of blind cooperation in conjunction with multihop communications. However, we show that blind cooperation is actually inefficient unless power control is applied. Inefficiency in this paper is projected in terms of the transport rate normalized to energy consumption. To that end, we propose an uncoordinated power control mechanism whereby each device in a blind cooperative cluster randomly adjusts its transmit power level. We derive an upper bound on the mean transmit power that must be observed at each device. We also devise a practical mechanism for each device to infer about the size of its neighborhood; a requirement necessary for the operation of the power control scheme. Finally, we assess the performance of the developed power control mechanism and demonstrate how it consistently outperforms the point-to-point case.

  4. Localized Power Control for Multihop Large-Scale Internet of Things

    KAUST Repository

    Bader, Ahmed

    2015-07-07

    In this paper, we promote the use of multihop networking in the context of large-scale Internet of Things (IoT). Recognizing concerns related to the scalability of classical multihop routing and medium access techniques, we advocate the use of blind cooperation in conjunction with multihop communications. However, we show that blind cooperation is actually inefficient unless power control is applied. Inefficiency in this paper is projected in terms of the transport rate normalized to energy consumption. To that end, we propose an uncoordinated power control mechanism whereby each device in a blind cooperative cluster randomly adjusts its transmit power level. We derive an upper bound on the mean transmit power that must be observed at each device. We also devise a practical mechanism for each device to infer about the size of its neighborhood; a requirement necessary for the operation of the power control scheme. Finally, we assess the performance of the developed power control mechanism and demonstrate how it consistently outperforms the point-to-point case.

  5. Fetal health locus of control: Scale properties and applications in preconception health programs.

    Science.gov (United States)

    Soliday, Elizabeth; Strahm, Anna; Mammenga, Stefani

    2016-04-01

    Preconception health programs have resulted in improved health behaviors among participants and have shown promise in reducing adverse birth outcomes. However, the role of health beliefs in preconception health program outcomes has been overlooked but warrants attention due to reported positive associations between women's views of control over fetal health and health behavior in pregnancy. Towards an ultimate aim of improving preconception health program reach and effectiveness, we examined properties of a fetal health locus of control (FHLC; Labs & Wurtele, 1986) measure in nulliparous, childbearing aged university women and men. Students (n=1467) completed an online survey that included the FHLC subscales maternal, powerful others', and chance control over fetal health. Factor analyses and correlations with related scales supported the soundness of FHLC constructs in both women and men. All participants rated maternal control in fetal health nearly twice as highly as powerful others' and chance. We therefore recommend that FHLC be integrated into preconception health program evaluation as personal agency in fetal health likely has an important role in women's and men's preconception health behavior and health behavior change. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Secure Access Control and Large Scale Robust Representation for Online Multimedia Event Detection

    Science.gov (United States)

    Liu, Changyu; Li, Huiling

    2014-01-01

    We developed an online multimedia event detection (MED) system. However, there are a secure access control issue and a large scale robust representation issue when we want to integrate traditional event detection algorithms into the online environment. For the first issue, we proposed a tree proxy-based and service-oriented access control (TPSAC) model based on the traditional role based access control model. Verification experiments were conducted on the CloudSim simulation platform, and the results showed that the TPSAC model is suitable for the access control of dynamic online environments. For the second issue, inspired by the object-bank scene descriptor, we proposed a 1000-object-bank (1000OBK) event descriptor. Feature vectors of the 1000OBK were extracted from response pyramids of 1000 generic object detectors which were trained on standard annotated image datasets, such as the ImageNet dataset. A spatial bag of words tiling approach was then adopted to encode these feature vectors for bridging the gap between the objects and events. Furthermore, we performed experiments in the context of event classification on the challenging TRECVID MED 2012 dataset, and the results showed that the robust 1000OBK event descriptor outperforms the state-of-the-art approaches. PMID:25147840

  7. H2, fixed architecture, control design for large scale systems. Ph.D. Thesis

    Science.gov (United States)

    Mercadal, Mathieu

    1990-01-01

    The H2, fixed architecture, control problem is a classic linear quadratic Gaussian (LQG) problem whose solution is constrained to be a linear time invariant compensator with a decentralized processing structure. The compensator can be made of p independent subcontrollers, each of which has a fixed order and connects selected sensors to selected actuators. The H2, fixed architecture, control problem allows the design of simplified feedback systems needed to control large scale systems. Its solution becomes more complicated, however, as more constraints are introduced. This work derives the necessary conditions for optimality for the problem and studies their properties. It is found that the filter and control problems couple when the architecture constraints are introduced, and that the different subcontrollers must be coordinated in order to achieve global system performance. The problem requires the simultaneous solution of highly coupled matrix equations. The use of homotopy is investigated as a numerical tool, and its convergence properties studied. It is found that the general constrained problem may have multiple stabilizing solutions, and that these solutions may be local minima or saddle points for the quadratic cost. The nature of the solution is not invariant when the parameters of the system are changed. Bifurcations occur, and a solution may continuously transform into a nonstabilizing compensator. Using a modified homotopy procedure, fixed architecture compensators are derived for models of large flexible structures to help understand the properties of the constrained solutions and compare them to the corresponding unconstrained ones.

  8. Landscape-Scale Controls on Aboveground Forest Carbon Stocks on the Osa Peninsula, Costa Rica

    Science.gov (United States)

    Taylor, Philip; Asner, Gregory; Dahlin, Kyla; Anderson, Christopher; Knapp, David; Martin, Roberta; Mascaro, Joseph; Chazdon, Robin; Cole, Rebecca; Wanek, Wolfgang; Hofhansl, Florian; Malavassi, Edgar; Vilchez-Alvarado, Braulio; Townsend, Alan

    2015-01-01

    Tropical forests store large amounts of carbon in tree biomass, although the environmental controls on forest carbon stocks remain poorly resolved. Emerging airborne remote sensing techniques offer a powerful approach to understand how aboveground carbon density (ACD) varies across tropical landscapes. In this study, we evaluate the accuracy of the Carnegie Airborne Observatory (CAO) Light Detection and Ranging (LiDAR) system to detect top-of-canopy tree height (TCH) and ACD across the Osa Peninsula, Costa Rica. LiDAR and field-estimated TCH and ACD were highly correlated across a wide range of forest ages and types. Top-of-canopy height (TCH) reached 67 m, and ACD surpassed 225 Mg C ha-1, indicating both that airborne CAO LiDAR-based estimates of ACD are accurate in tall, high-biomass forests and that the Osa Peninsula harbors some of the most carbon-rich forests in the Neotropics. We also examined the relative influence of lithologic, topoedaphic and climatic factors on regional patterns in ACD, which are known to influence ACD by regulating forest productivity and turnover. Analyses revealed a spatially nested set of factors controlling ACD patterns, with geologic variation explaining up to 16% of the mapped ACD variation at the regional scale, while local variation in topographic slope explained an additional 18%. Lithologic and topoedaphic factors also explained more ACD variation at 30-m than at 100-m spatial resolution, suggesting that environmental filtering depends on the spatial scale of terrain variation. Our result indicate that patterns in ACD are partially controlled by spatial variation in geologic history and geomorphic processes underpinning topographic diversity across landscapes. ACD also exhibited spatial autocorrelation, which may reflect biological processes that influence ACD, such as the assembly of species or phenotypes across the landscape, but additional research is needed to resolve how abiotic and biotic factors contribute to ACD

  9. Landscape-Scale Controls on Aboveground Forest Carbon Stocks on the Osa Peninsula, Costa Rica.

    Directory of Open Access Journals (Sweden)

    Philip Taylor

    Full Text Available Tropical forests store large amounts of carbon in tree biomass, although the environmental controls on forest carbon stocks remain poorly resolved. Emerging airborne remote sensing techniques offer a powerful approach to understand how aboveground carbon density (ACD varies across tropical landscapes. In this study, we evaluate the accuracy of the Carnegie Airborne Observatory (CAO Light Detection and Ranging (LiDAR system to detect top-of-canopy tree height (TCH and ACD across the Osa Peninsula, Costa Rica. LiDAR and field-estimated TCH and ACD were highly correlated across a wide range of forest ages and types. Top-of-canopy height (TCH reached 67 m, and ACD surpassed 225 Mg C ha-1, indicating both that airborne CAO LiDAR-based estimates of ACD are accurate in tall, high-biomass forests and that the Osa Peninsula harbors some of the most carbon-rich forests in the Neotropics. We also examined the relative influence of lithologic, topoedaphic and climatic factors on regional patterns in ACD, which are known to influence ACD by regulating forest productivity and turnover. Analyses revealed a spatially nested set of factors controlling ACD patterns, with geologic variation explaining up to 16% of the mapped ACD variation at the regional scale, while local variation in topographic slope explained an additional 18%. Lithologic and topoedaphic factors also explained more ACD variation at 30-m than at 100-m spatial resolution, suggesting that environmental filtering depends on the spatial scale of terrain variation. Our result indicate that patterns in ACD are partially controlled by spatial variation in geologic history and geomorphic processes underpinning topographic diversity across landscapes. ACD also exhibited spatial autocorrelation, which may reflect biological processes that influence ACD, such as the assembly of species or phenotypes across the landscape, but additional research is needed to resolve how abiotic and biotic factors

  10. Canopy-scale biophysical controls of transpiration and evaporation in the Amazon Basin

    Directory of Open Access Journals (Sweden)

    K. Mallick

    2016-10-01

    Full Text Available Canopy and aerodynamic conductances (gC and gA are two of the key land surface biophysical variables that control the land surface response of land surface schemes in climate models. Their representation is crucial for predicting transpiration (λET and evaporation (λEE flux components of the terrestrial latent heat flux (λE, which has important implications for global climate change and water resource management. By physical integration of radiometric surface temperature (TR into an integrated framework of the Penman–Monteith and Shuttleworth–Wallace models, we present a novel approach to directly quantify the canopy-scale biophysical controls on λET and λEE over multiple plant functional types (PFTs in the Amazon Basin. Combining data from six LBA (Large-scale Biosphere-Atmosphere Experiment in Amazonia eddy covariance tower sites and a TR-driven physically based modeling approach, we identified the canopy-scale feedback-response mechanism between gC, λET, and atmospheric vapor pressure deficit (DA, without using any leaf-scale empirical parameterizations for the modeling. The TR-based model shows minor biophysical control on λET during the wet (rainy seasons where λET becomes predominantly radiation driven and net radiation (RN determines 75 to 80 % of the variances of λET. However, biophysical control on λET is dramatically increased during the dry seasons, and particularly the 2005 drought year, explaining 50 to 65 % of the variances of λET, and indicates λET to be substantially soil moisture driven during the rainfall deficit phase. Despite substantial differences in gA between forests and pastures, very similar canopy–atmosphere "coupling" was found in these two biomes due to soil moisture-induced decrease in gC in the pasture. This revealed the pragmatic aspect of the TR-driven model behavior that exhibits a high sensitivity of gC to per unit change in wetness as opposed to gA that is marginally sensitive to

  11. Standardization of the Self Control and Self-Management Skills Scale (SCMS) on the Student of University of Najran

    Science.gov (United States)

    Al-Smadi, Marwan Saleh; Bani-Abduh, Yahya Mohammed

    2017-01-01

    This study aimed to standardize self-control and self-management skills (SCMS), Mezo 2009 , on students in the university of Najran And to identify the psychometric properties of the scale in the Arab Environment the society of Najran University student by taking a number of Procedures (Validity and reliability of the Scale ) and to get the Arabic…

  12. Ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach

    National Research Council Canada - National Science Library

    Christianson, David; Creel, Scott

    2014-01-01

    ... reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects...

  13. Empirical evidence for multi-scaled controls on wildfire size distributions in California

    Science.gov (United States)

    Povak, N.; Hessburg, P. F., Sr.; Salter, R. B.

    2014-12-01

    Ecological theory asserts that regional wildfire size distributions are examples of self-organized critical (SOC) systems. Controls on SOC event-size distributions by virtue are purely endogenous to the system and include the (1) frequency and pattern of ignitions, (2) distribution and size of prior fires, and (3) lagged successional patterns after fires. However, recent work has shown that the largest wildfires often result from extreme climatic events, and that patterns of vegetation and topography may help constrain local fire spread, calling into question the SOC model's simplicity. Using an atlas of >12,000 California wildfires (1950-2012) and maximum likelihood estimation (MLE), we fit four different power-law models and broken-stick regressions to fire-size distributions across 16 Bailey's ecoregions. Comparisons among empirical fire size distributions across ecoregions indicated that most ecoregion's fire-size distributions were significantly different, suggesting that broad-scale top-down controls differed among ecoregions. One-parameter power-law models consistently fit a middle range of fire sizes (~100 to 10000 ha) across most ecoregions, but did not fit to larger and smaller fire sizes. We fit the same four power-law models to patch size distributions of aspect, slope, and curvature topographies and found that the power-law models fit to a similar middle range of topography patch sizes. These results suggested that empirical evidence may exist for topographic controls on fire sizes. To test this, we used neutral landscape modeling techniques to determine if observed fire edges corresponded with aspect breaks more often than expected by random. We found significant differences between the empirical and neutral models for some ecoregions, particularly within the middle range of fire sizes. Our results, combined with other recent work, suggest that controls on ecoregional fire size distributions are multi-scaled and likely are not purely SOC. California

  14. Factorial invariance, scale reliability, and construct validity of the job control and job demands scales for immigrant workers: The Multi-Ethnic Study of Atherosclerosis (MESA)

    Science.gov (United States)

    Fujishiro, Kaori; Landsbergis, Paul; Roux, Ana V. Diez; Stukovsky, Karen Hinckley; Shrager, Sandi; Baron, Sherry

    2014-01-01

    Immigrants have a different social context from those who stay in their home country or those who were born to the country that immigrants now live. Cultural theory of risk perception suggests that social context influences one’s interpretation of questionnaire items. We examined psychometric properties of job control and job demand scales with US- and foreign-born workers who preferred English, Spanish, or Chinese (n=3114, mean age=58.1). Across all groups, the job control scale had acceptable Cronbach’s alpha (0.78–0.83) and equivalent factor loadings (ΔCFI<0.01). Immigrants had low alpha (0.42–0.65) for the job demands scale regardless of language, education, or age of migration. Two job-demand items had different factor loadings across groups. Among immigrants, both scales had inconsistent associations with perceived job stress and self-rated health. For a better understanding of immigrants’ job stress, the concept of job demands should be expanded and immigrants’ expectations for job control explored. (149/150 limit) PMID:20582720

  15. Factorial invariance, scale reliability, and construct validity of the job control and job demands scales for immigrant workers: the multi-ethnic study of atherosclerosis.

    Science.gov (United States)

    Fujishiro, Kaori; Landsbergis, Paul A; Diez-Roux, Ana V; Stukovsky, Karen Hinckley; Shrager, Sandi; Baron, Sherry

    2011-06-01

    Immigrants have a different social context from those who stay in their home country or those who were born to the country that immigrants now live. Cultural theory of risk perception suggests that social context influences one's interpretation of questionnaire items. We examined psychometric properties of job control and job demand scales with US- and foreign-born workers who preferred English, Spanish, or Chinese (n = 3,114, mean age = 58.1). Across all groups, the job control scale had acceptable Cronbach's alpha (0.78-0.83) and equivalent factor loadings (ΔCFI < 0.01). Immigrants had low alpha (0.42-0.65) for the job demands scale regardless of language, education, or age of migration. Two job-demand items had different factor loadings across groups. Among immigrants, both scales had inconsistent associations with perceived job stress and self-rated health. For a better understanding of immigrants' job stress, the concept of job demands should be expanded and immigrants' expectations for job control explored.

  16. Climatic and physiographic controls on catchment-scale nitrate loss at different spatial scales: insights from a top-down model development approach

    Science.gov (United States)

    Shafii, Mahyar; Basu, Nandita; Schiff, Sherry; Van Cappellen, Philippe

    2017-04-01

    Dramatic increase in nitrogen circulating in the biosphere due to anthropogenic activities has resulted in impairment of water quality in groundwater and surface water causing eutrophication in coastal regions. Understanding the fate and transport of nitrogen from landscape to coastal areas requires exploring the drivers of nitrogen processes in both time and space, as well as the identification of appropriate flow pathways. Conceptual models can be used as diagnostic tools to provide insights into such controls. However, diagnostic evaluation of coupled hydrological-biogeochemical models is challenging. This research proposes a top-down methodology utilizing hydrochemical signatures to develop conceptual models for simulating the integrated streamflow and nitrate responses while taking into account dominant controls on nitrate variability (e.g., climate, soil water content, etc.). Our main objective is to seek appropriate model complexity that sufficiently reproduces multiple hydrological and nitrate signatures. Having developed a suitable conceptual model for a given watershed, we employ it in sensitivity studies to demonstrate the dominant process controls that contribute to the nitrate response at scales of interest. We apply the proposed approach to nitrate simulation in a range of small to large sub-watersheds in the Grand River Watershed (GRW) located in Ontario. Such multi-basin modeling experiment will enable us to address process scaling and investigate the consequences of lumping processes in terms of models' predictive capability. The proposed methodology can be applied to the development of large-scale models that can help decision-making associated with nutrients management at regional scale.

  17. Simulated control in Aspen Dynamics for the production of limonene epoxide at pilot scale

    Directory of Open Access Journals (Sweden)

    Yeison Agudelo Arenas

    2016-12-01

    Full Text Available In this contribution is reported the study and analysis of the control system (simulated for the process of obtaining limonene epoxide. The modelling of the process at pilot scale was implemented in the software Aspen Plus from literature reports. Aspen Dynamics was used for the study of the process control. The model allows observing the behavior of the variables of interest in the process such as outflows from the distillation tower, heat duty, operating temperaturas and purity of the final product (limonene epoxide. The performance of the controllers (level, flow and temperature was evaluated by simulating disturbances (+30% in the feedstream to the process. Sensitivity analysis and preliminary design specifications allow to conclude that according to the simulations it is possible to obtain limonene epoxide (97,5% w/w with this system. The results of this work can be used for more detailed studies of the system, including experimental study designs that help to determine the operating point for the process variables which increase limonene epoxide production.

  18. Full Scale Bioreactor Landfill for Carbon Sequestration and Greenhouse Emission Control

    Energy Technology Data Exchange (ETDEWEB)

    Ramin Yazdani; Jeff Kieffer; Kathy Sananikone; Don Augenstein

    2005-03-30

    The Yolo County Department of Planning and Public Works constructed a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective was to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entailed the construction of a 12-acre module that contained a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells were highly instrumented to monitor bioreactor performance. Liquid addition commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell and biofilter has been completed. The current project status and preliminary monitoring results are summarized in this report.

  19. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-12-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Liquid addition has commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell and biofilter has been completed. The remaining task to be completed is to test the biofilter prior to operation, which is currently anticipated to begin in January 2004. The current project status and preliminary monitoring results are summarized in this report.

  20. Aerodynamics, sensing and control of insect-scale flapping-wing flight

    Science.gov (United States)

    Shyy, Wei; Kang, Chang-kwon; Chirarattananon, Pakpong; Ravi, Sridhar; Liu, Hao

    2016-01-01

    There are nearly a million known species of flying insects and 13 000 species of flying warm-blooded vertebrates, including mammals, birds and bats. While in flight, their wings not only move forward relative to the air, they also flap up and down, plunge and sweep, so that both lift and thrust can be generated and balanced, accommodate uncertain surrounding environment, with superior flight stability and dynamics with highly varied speeds and missions. As the size of a flyer is reduced, the wing-to-body mass ratio tends to decrease as well. Furthermore, these flyers use integrated system consisting of wings to generate aerodynamic forces, muscles to move the wings, and sensing and control systems to guide and manoeuvre. In this article, recent advances in insect-scale flapping-wing aerodynamics, flexible wing structures, unsteady flight environment, sensing, stability and control are reviewed with perspective offered. In particular, the special features of the low Reynolds number flyers associated with small sizes, thin and light structures, slow flight with comparable wind gust speeds, bioinspired fabrication of wing structures, neuron-based sensing and adaptive control are highlighted. PMID:27118897

  1. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-05-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Construction is complete on the 3.5-acre anaerobic cell and liquid addition has commenced. Construction of the 2.5-acre aerobic cell is nearly complete with only the biofilter remaining and construction of the west-side 6-acre anaerobic cell is nearly complete with only the liquid addition system remaining. The current project status and preliminary monitoring results are summarized in this report.

  2. FULL SCALE BIOREACTOR LANDFILL FOR CARBON SEQUESTRATION AND GREENHOUSE EMISSION CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Ramin Yazdani; Jeff Kieffer; Heather Akau

    2003-08-01

    The Yolo County Department of Planning and Public Works is constructing a full-scale bioreactor landfill as a part of the Environmental Protection Agency's (EPA) Project XL program to develop innovative approaches for carbon sequestration and greenhouse emission control. The overall objective is to manage landfill solid waste for rapid waste decomposition and maximum landfill gas generation and capture for carbon sequestration and greenhouse emission control. Waste decomposition is accelerated by improving conditions for either the aerobic or anaerobic biological processes and involves circulating controlled quantities of liquid (leachate, groundwater, gray water, etc.), and, in the aerobic process, large volumes of air. The first phase of the project entails the construction of a 12-acre module that contains a 6-acre anaerobic cell, a 3.5-acre anaerobic cell, and a 2.5-acre aerobic cell at the Yolo County Central Landfill near Davis, California. The cells are highly instrumented to monitor bioreactor performance. Liquid addition has commenced in the 3.5-acre anaerobic cell and the 6-acre anaerobic cell. Construction of the 2.5-acre aerobic cell is nearly complete with only the biofilter remaining and is scheduled to be complete by the end of August 2003. The current project status and preliminary monitoring results are summarized in this report.

  3. Aerodynamics, sensing and control of insect-scale flapping-wing flight.

    Science.gov (United States)

    Shyy, Wei; Kang, Chang-Kwon; Chirarattananon, Pakpong; Ravi, Sridhar; Liu, Hao

    2016-02-01

    There are nearly a million known species of flying insects and 13 000 species of flying warm-blooded vertebrates, including mammals, birds and bats. While in flight, their wings not only move forward relative to the air, they also flap up and down, plunge and sweep, so that both lift and thrust can be generated and balanced, accommodate uncertain surrounding environment, with superior flight stability and dynamics with highly varied speeds and missions. As the size of a flyer is reduced, the wing-to-body mass ratio tends to decrease as well. Furthermore, these flyers use integrated system consisting of wings to generate aerodynamic forces, muscles to move the wings, and sensing and control systems to guide and manoeuvre. In this article, recent advances in insect-scale flapping-wing aerodynamics, flexible wing structures, unsteady flight environment, sensing, stability and control are reviewed with perspective offered. In particular, the special features of the low Reynolds number flyers associated with small sizes, thin and light structures, slow flight with comparable wind gust speeds, bioinspired fabrication of wing structures, neuron-based sensing and adaptive control are highlighted.

  4. Regional parent flood frequency distributions in Europe – Part 2: Climate and scale controls

    Directory of Open Access Journals (Sweden)

    J. L. Salinas

    2014-11-01

    Full Text Available This study aims to better understand the effect of catchment scale and climate on the statistical properties of regional flood frequency distributions. A database of L-moment ratios of annual maximum series (AMS of peak discharges from Austria, Italy and Slovakia, involving a total of 813 catchments with more than 25 yr of record length is presented, together with mean annual precipitation (MAP and basin area as catchment descriptors surrogates of climate and scale controls. A purely data-based investigation performed on the database shows that the generalized extreme value (GEV distribution provides a better representation of the averaged sample L-moment ratios compared to the other distributions considered, for catchments with medium to higher values of MAP independently of catchment area, while the three-parameter lognormal distribution is probably a more appropriate choice for drier (lower MAP intermediate-sized catchments, which presented higher skewness values. Sample L-moment ratios do not follow systematically any of the theoretical two-parameter distributions. In particular, the averaged values of L-coefficient of skewness (L-Cs are always larger than Gumbel's fixed L-Cs. The results presented in this paper contribute to the progress in defining a set of "process-driven" pan-European flood frequency distributions and to assess possible effects of environmental change on its properties.

  5. Distributed Data Logging and Intelligent Control Strategies for a Scaled Autonomous Vehicle

    Directory of Open Access Journals (Sweden)

    Tilman Happek

    2016-04-01

    Full Text Available In this paper we present an autonomous car with distributed data processing. The car is controlled by a multitude of independent sensors. For the lane detection, a camera is used, which detects the lane marks with a Hough transformation. Once the camera detects these, one of them is calculated to be followed by the car. This lane is verified by the other sensors of the car. These sensors check the route for obstructions or allow the car to scan a parking space and to park on the roadside if the gap is large enough. The car is built on a scale of 1:10 and shows excellent results on a test track.

  6. A multi-scale residual-based anti-hourglass control for compatible staggered Lagrangian hydrodynamics

    Science.gov (United States)

    Kucharik, M.; Scovazzi, G.; Shashkov, M.; Loubère, R.

    2018-02-01

    Hourglassing is a well-known pathological numerical artifact affecting the robustness and accuracy of Lagrangian methods. There exist a large number of hourglass control/suppression strategies. In the community of the staggered compatible Lagrangian methods, the approach of sub-zonal pressure forces is among the most widely used. However, this approach is known to add numerical strength to the solution, which can cause potential problems in certain types of simulations, for instance in simulations of various instabilities. To avoid this complication, we have adapted the multi-scale residual-based stabilization typically used in the finite element approach for staggered compatible framework. In this paper, we describe two discretizations of the new approach and demonstrate their properties and compare with the method of sub-zonal pressure forces on selected numerical problems.

  7. Micrometre-scale deformation observations reveal fundamental controls on geological rifting.

    Science.gov (United States)

    Thun, Johannes; Lokmer, Ivan; Bean, Christopher J; Eibl, Eva P S; Bergsson, Bergur H; Braiden, Aoife

    2016-11-09

    Many of the world's largest volcanic eruptions are associated with geological rifting where major fractures open at the Earth's surface, yet fundamental controls on the near-surface response to the rifting process are lacking. New high resolution observations gleaned from seismometer data during the 2014 Bárðarbunga basaltic dyke intrusion in Iceland allow us unprecedented access to the associated graben formation process on both sub-second and micrometre scales. We find that what appears as quasi steady-state near-surface rifting on lower resolution GPS observation comprises discrete staccato-like deformation steps as the upper crust unzips through repetitive low magnitude (MW earthquakes, demonstrating that the uppermost crust in the rift zone is exceptionally weak.

  8. Dispersion free control of hydroelastic waves down to sub-wavelength scale

    Science.gov (United States)

    Domino, Lucie; Fermigier, Marc; Fort, Emmanuel; Eddi, Antonin

    2017-11-01

    Hydroelastic surface waves propagate at the surface of water covered by a thin elastic sheet and can be directly measured with accurate space and time resolution. We present an experimental approach using hydroelastic waves that allows us to control waves down to the sub-wavelength scale. We tune the wave dispersion relation by varying locally the properties of the elastic cover and we introduce a local index contrast. This index contrast is independent of the frequency leading to a dispersion-free Snell-Descartes law for hydroelastic waves. We then show experimental evidence of broadband focusing, reflection and refraction of the waves. We also investigate the limits of diffraction through the example of a macroscopic analog to optical nanojets, revealing that any sub-wavelength configuration gives access to new features for surface waves.

  9. Scale dependence of controls on groundwater vulnerability in the water–energy–food nexus, California Coastal Basin aquifer system

    Directory of Open Access Journals (Sweden)

    Jason J. Gurdak

    2017-06-01

    New hydrological insights for the region: Dissolved oxygen (DO (attenuation in groundwater is often the most significant STA factor in all model domains, indicating that DO is an important, scale-invariant factor controlling NPS NO3− contamination. Farm fertilizer (source is also a significant scale-invariant factor, while many of the transport factors are scale-dependent factors. We present vulnerability maps that illustrate the spatial patterns of predicted probability of detected elevated NO3−. Findings here improve knowledge about the scale dependence of STA factors, which help decision makers develop best management strategies and policies that advances groundwater sustainability and optimizes the WEF Nexus.

  10. Hydrodynamic parameters estimation from self-potential data in a controlled full scale site

    Science.gov (United States)

    Chidichimo, Francesco; De Biase, Michele; Rizzo, Enzo; Masi, Salvatore; Straface, Salvatore

    2015-03-01

    A multi-physical approach developed for the hydrodynamic characterization of porous media using hydrogeophysical information is presented. Several pumping tests were performed in the Hydrogeosite Laboratory, a controlled full-scale site designed and constructed at the CNR-IMAA (Consiglio Nazionale delle Ricerche - Istituto di Metodologia per l'Analisi Ambientale), in Marsico Nuovo (Basilicata Region, Southern Italy), in order to obtain an intermediate stage between laboratory experiments and field survey. The facility consists of a pool, used to study water infiltration processes, to simulate the space and time dynamics of subsurface contamination phenomena, to improve and to find new relationship between geophysical and hydrogeological parameters, to test and to calibrate new geophysical techniques and instruments. Therefore, the Hydrogeosite Laboratory has the advantage of carrying out controlled experiments, like in a flow cell or sandbox, but at field comparable scale. The data collected during the experiments have been used to estimate the saturated hydraulic conductivity ks [ms-1] using a coupled inversion model working in transient conditions, made up of the modified Richards equation describing the water flow in a variably saturated porous medium and the Poisson equation providing the self-potential ϕ [V], which naturally occurs at points of the soil surface owing to the presence of an electric field produced by the motion of underground electrolytic fluids through porous systems. The result obtained by this multi-physical numerical approach, which removes all the approximations adopted in previous works, makes a useful instrument for real heterogeneous aquifer characterization and for predictive analysis of its behavior.

  11. Tree-, stand- and site-specific controls on landscape-scale patterns of transpiration

    Science.gov (United States)

    Kathrin Hassler, Sibylle; Weiler, Markus; Blume, Theresa

    2018-01-01

    Transpiration is a key process in the hydrological cycle, and a sound understanding and quantification of transpiration and its spatial variability is essential for management decisions as well as for improving the parameterisation and evaluation of hydrological and soil-vegetation-atmosphere transfer models. For individual trees, transpiration is commonly estimated by measuring sap flow. Besides evaporative demand and water availability, tree-specific characteristics such as species, size or social status control sap flow amounts of individual trees. Within forest stands, properties such as species composition, basal area or stand density additionally affect sap flow, for example via competition mechanisms. Finally, sap flow patterns might also be influenced by landscape-scale characteristics such as geology and soils, slope position or aspect because they affect water and energy availability; however, little is known about the dynamic interplay of these controls.We studied the relative importance of various tree-, stand- and site-specific characteristics with multiple linear regression models to explain the variability of sap velocity measurements in 61 beech and oak trees, located at 24 sites across a 290 km2 catchment in Luxembourg. For each of 132 consecutive days of the growing season of 2014 we modelled the daily sap velocity and derived sap flow patterns of these 61 trees, and we determined the importance of the different controls.Results indicate that a combination of mainly tree- and site-specific factors controls sap velocity patterns in the landscape, namely tree species, tree diameter, geology and aspect. For sap flow we included only the stand- and site-specific predictors in the models to ensure variable independence. Of those, geology and aspect were most important. Compared to these predictors, spatial variability of atmospheric demand and soil moisture explains only a small fraction of the variability in the daily datasets. However, the temporal

  12. Charge screening strategy for domain pattern control in nano-scale ferroelectric systems.

    Science.gov (United States)

    Yamada, Tomoaki; Ito, Daisuke; Sluka, Tomas; Sakata, Osami; Tanaka, Hidenori; Funakubo, Hiroshi; Namazu, Takahiro; Wakiya, Naoki; Yoshino, Masahito; Nagasaki, Takanori; Setter, Nava

    2017-07-12

    Strain engineering is a widespread strategy used to enhance performance of devices based on semiconductor thin films. In ferroelectrics strain engineering is used to control the domain pattern: When an epitaxial film is biaxially compressed, e.g. due to lattice mismatch with the substrate, the film displays out-of-plane, often strongly enhanced polarization, while stretching the film on the substrate results in in-plane polarization. However, this strategy is of a limited applicability in nanorods because of the small rod/substrate contact area. Here we demonstrate another strategy, in which the polar axis direction is controlled by charge screening. When charge screening is maintained by bottom and top metallization, the nanorods display an almost pure c-domain configuration (polarization perpendicular to the substrate); when the sidewalls of the nanorods are metallized too, a-domain formation prevails (polarization parallel to the substrate). Simulations of the depolarization fields under various boundary conditions support the experimental observations. The employed approach can be expanded to other low-dimensional nano-scale ferroelectric systems.

  13. A multi-scale controlled tissue engineering scaffold prepared by 3D printing and NFES technology

    Directory of Open Access Journals (Sweden)

    Feifei Yan

    2014-03-01

    Full Text Available The current focus in the field of life science is the use of tissue engineering scaffolds to repair human organs, which has shown great potential in clinical applications. Extracellular matrix morphology and the performance and internal structure of natural organs are required to meet certain requirements. Therefore, integrating multiple processes can effectively overcome the limitations of the individual processes and can take into account the needs of scaffolds for the material, structure, mechanical properties and many other aspects. This study combined the biological 3D printing technology and the near-field electro-spinning (NFES process to prepare a multi-scale controlled tissue engineering scaffold. While using 3D printing technology to directly prepare the macro-scaffold, the compositing NFES process to build tissue micro-morphology ultimately formed a tissue engineering scaffold which has the specific extracellular matrix structure. This scaffold not only takes into account the material, structure, performance and many other requirements, but also focuses on resolving the controllability problems in macro- and micro-forming which further aim to induce cell directed differentiation, reproduction and, ultimately, the formation of target tissue organs. It has in-depth immeasurable significance to build ideal scaffolds and further promote the application of tissue engineering.

  14. Effect of organic on chemical oxidation for biofouling control in pilot-scale seawater cooling towers

    KAUST Repository

    Al-Bloushi, Mohammed

    2017-09-14

    Due to the scarcity of potable water in many regions of the world, the demand for seawater as an alternative evaporative cooling medium in cooling towers (CTs) has increased significantly in recent years. Seawater make-up in CTs is deemed the most feasible because of its unlimited supply in the coastal areas of Gulf and Red Sea. However, the seawater CTs have higher challenges greatly mitigating their performances because it is an open system where biofouling and bio-corrosion occurring within the fillers and piping of recirculation systems. Their pilot-scale CTs were constructed to assess the performance of three types of oxidizing biocides or oxidants, namely chlorine, chlorine dioxide (ClO2) and ozone, for biofouling control. The test results showed that the addition of organic (5mg/L of methanol (MeOH)) increased the bacterial growth in CT basin. All oxidants were effective in keeping the microbial growth to the minimum. Oxidation increased the oxidation-reduction potential (ORP) level from 270 to 600mV. Total residual oxidant (TRO) was increased with oxidation but it was slightly increased with organic addition. Other parameters including pH, dissolved oxygen (DO), conductivity levels were not changed. However, higher formation of disinfection by-products (DBPs) was detected with chlorination and ozonation. This indicates the organic level should be limited in the oxidation for biofouling control in seawater CTs.

  15. Understanding the physical properties controlling protein crystallization based on analysis of large-scale experimental data

    Science.gov (United States)

    Price, W. Nicholson; Chen, Yang; Handelman, Samuel K.; Neely, Helen; Manor, Philip; Karlin, Richard; Nair, Rajesh; Liu, Jinfeng; Baran, Michael; Everett, John; Tong, Saichiu N.; Forouhar, Farhad; Swaminathan, Swarup S.; Acton, Thomas; Xiao, Rong; Luft, Joseph R.; Lauricella, Angela; DeTitta, George T.; Rost, Burkhard; Montelione, Gaetano T.; Hunt, John F.

    2009-01-01

    Crystallization has proven to be the most significant bottleneck to high-throughput protein structure determination using diffraction methods. We have used the large-scale, systematically generated experimental results of the Northeast Structural Genomics Consortium to characterize the biophysical properties that control protein crystallization. Datamining of crystallization results combined with explicit folding studies lead to the conclusion that crystallization propensity is controlled primarily by the prevalence of well-ordered surface epitopes capable of mediating interprotein interactions and is not strongly influenced by overall thermodynamic stability. These analyses identify specific sequence features correlating with crystallization propensity that can be used to estimate the crystallization probability of a given construct. Analyses of entire predicted proteomes demonstrate substantial differences in the bulk amino acid sequence properties of human versus eubacterial proteins that reflect likely differences in their biophysical properties including crystallization propensity. Finally, our thermodynamic measurements enable critical evaluation of previous claims regarding correlations between protein stability and bulk sequence properties, which generally are not supported by our dataset. PMID:19079241

  16. "APEC Blue" association with emission control and meteorological conditions detected by multi-scale statistics

    Science.gov (United States)

    Wang, Ping; Dai, Xin-Gang

    2016-09-01

    The term "APEC Blue" has been created to describe the clear sky days since the Asia-Pacific Economic Cooperation (APEC) summit held in Beijing during November 5-11, 2014. The duration of the APEC Blue is detected from November 1 to November 14 (hereafter Blue Window) by moving t test in statistics. Observations show that APEC Blue corresponds to low air pollution with respect to PM2.5, PM10, SO2, and NO2 under strict emission-control measures (ECMs) implemented in Beijing and surrounding areas. Quantitative assessment shows that ECM is more effective on reducing aerosols than the chemical constituents. Statistical investigation has revealed that the window also resulted from intensified wind variability, as well as weakened static stability of atmosphere (SSA). The wind and ECMs played key roles in reducing air pollution during November 1-7 and 11-13, and strict ECMs and weak SSA become dominant during November 7-10 under weak wind environment. Moving correlation manifests that the emission reduction for aerosols can increase the apparent wind cleanup effect, leading to significant negative correlations of them, and the period-wise changes in emission rate can be well identified by multi-scale correlations basing on wavelet decomposition. In short, this case study manifests statistically how human interference modified air quality in the mega city through controlling local and surrounding emissions in association with meteorological condition.

  17. Heart valve scaffold fabrication: Bioinspired control of macro-scale morphology, mechanics and micro-structure.

    Science.gov (United States)

    D'Amore, Antonio; Luketich, Samuel K; Raffa, Giuseppe M; Olia, Salim; Menallo, Giorgio; Mazzola, Antonino; D'Accardi, Flavio; Grunberg, Tamir; Gu, Xinzhu; Pilato, Michele; Kameneva, Marina V; Badhwar, Vinay; Wagner, William R

    2018-01-01

    Valvular heart disease is currently treated with mechanical valves, which benefit from longevity, but are burdened by chronic anticoagulation therapy, or with bioprosthetic valves, which have reduced thromboembolic risk, but limited durability. Tissue engineered heart valves have been proposed to resolve these issues by implanting a scaffold that is replaced by endogenous growth, leaving autologous, functional leaflets that would putatively eliminate the need for anticoagulation and avoid calcification. Despite the diversity in fabrication strategies and encouraging results in large animal models, control over engineered valve structure-function remains at best partial. This study aimed to overcome these limitations by introducing double component deposition (DCD), an electrodeposition technique that employs multi-phase electrodes to dictate valve macro and microstructure and resultant function. Results in this report demonstrate the capacity of the DCD method to simultaneously control scaffold macro-scale morphology, mechanics and microstructure while producing fully assembled stent-less multi-leaflet valves composed of microscopic fibers. DCD engineered valve characterization included: leaflet thickness, biaxial properties, bending properties, and quantitative structural analysis of multi-photon and scanning electron micrographs. Quasi-static ex-vivo valve coaptation testing and dynamic organ level functional assessment in a pressure pulse duplicating device demonstrated appropriate acute valve functionality. Copyright © 2017. Published by Elsevier Ltd.

  18. Fine and nanometer scaled particle behavior characterization and control for sustainable energy and environmental technology

    Energy Technology Data Exchange (ETDEWEB)

    Hidehiro Kamiya; Mayumi Tsukada; Wuled Lenggoro; Wladyslaw W. Szymanski [Tokyo University of Agriculture and Technology, Tokyo (Japan)

    2008-07-01

    Characterization and control of fine and nanometer scaled particles are essential technological fundamentals for understanding and development of various approaches concerned with sustainable energy and environmental technology, for example, PM10/PM2.5 and nanoparticle emission, clean and high efficiency power generation systems from biomass and solid waste combustion. The standard measuring methods for PM10/PM2.5 and nanoparticle emission behavior from stationary sources, such as coal-fired power plants and waste incinerators, have been discussed in ISO and numerous countries. However, it is difficult to evaluate the actual emission amount and particle size distribution, such as condensable suspended particulate matter, condensable SPM, which is nucleated and grow during cooling and diluting process from flue to atmosphere. High temperature gas cleaning using rigid ceramic filters is an important technology to develop high efficiency power generation system. In this paper, based on the review of background and recent research works of each subject, mass concentration measurement method of PM10/PM2.5 and size distribution of condensable SPM from stationary sources are introduced. Subsequently, research results with focus on ash adhesion behavior characterization and control for the development of dust collection and gas cleaning technology at high temperature conditions in high efficiency power generation systems by coal, biomass and solid waste combustion are presented. 12 refs., 7 figs., 3 tabs.

  19. Tree-, stand- and site-specific controls on landscape-scale patterns of transpiration

    Science.gov (United States)

    Hassler, Sibylle; Markus, Weiler; Theresa, Blume

    2017-04-01

    Transpiration is a key process in the hydrological cycle and a sound understanding and quantification of transpiration and its spatial variability is essential for management decisions as well as for improving the parameterisation of hydrological and soil-vegetation-atmosphere transfer models. For individual trees, transpiration is commonly estimated by measuring sap flow. Besides evaporative demand and water availability, tree-specific characteristics such as species, size or social status control sap flow amounts of individual trees. Within forest stands, properties such as species composition, basal area or stand density additionally affect sap flow, for example via competition mechanisms. Finally, sap flow patterns might also be influenced by landscape-scale characteristics such as geology, slope position or aspect because they affect water and energy availability; however, little is known about the dynamic interplay of these controls. We studied the relative importance of various tree-, stand- and site-specific characteristics with multiple linear regression models to explain the variability of sap velocity measurements in 61 beech and oak trees, located at 24 sites spread over a 290 km2-catchment in Luxembourg. For each of 132 consecutive days of the growing season of 2014 we modelled the daily sap velocities of these 61 trees and determined the importance of the different predictors. Results indicate that a combination of tree-, stand- and site-specific factors controls sap velocity patterns in the landscape, namely tree species, tree diameter, the stand density, geology and aspect. Compared to these predictors, spatial variability of atmospheric demand and soil moisture explains only a small fraction of the variability in the daily datasets. However, the temporal dynamics of the explanatory power of the tree-specific characteristics, especially species, are correlated to the temporal dynamics of potential evaporation. Thus, transpiration estimates at the

  20. Measuring Armenia's progress on the Tobacco Control Scale: an evaluation of tobacco control in an economy in transition, 2005-2009.

    Science.gov (United States)

    Movsisyan, Narine K; Connolly, Gregory N

    2014-02-27

    This study aimed to measure the 5-year progress in the implementation of WHO Framework Convention on Tobacco Control (FCTC) in Armenia by applying the Tobacco Control Scale, a rapid assessment tool developed to assess the strength of tobacco control policies in Europe. Armenia, an economy in transition, has extreme smoking rates among men (62.5%) despite acceding to FCTC in 2004. However, little research has been carried out to evaluate Armenia's progress in tobacco control. The Tobacco Control Scale total score was estimated for Armenia using the original methodology; however, a different source of data was used in estimating the subscores on tobacco price and tobacco control spending. Armenia's total score on Tobacco Control Scale has considerably improved from 2005 to 2009, mostly due to larger health warnings and advertising ban, and increased public spending on tobacco control. The scores for smoke-free public places, advertising ban, health warnings and treatment categories were below the European average in 2005 and 2007, while the price score was higher. Neither total tobacco control score nor any of its components showed a significant predictive value in a simple regression analysis using the total score and subscores as predictors for log-transformed per capita tobacco consumption. Higher than the European average price score for Armenia cannot be explained by the concept of affordability alone and may reflect a measurement error due to peculiarities of transition economies. The applicability of the Tobacco Control Scale could be limited to countries with mature economies, but not to transition countries such as Armenia with different social, political and economic environment. The scale modification, such as an adjustment for the policy enforcement and the effectiveness of public tobacco control spending along with alternative measures of affordability would be warranted to enhance its applicability in low-income and middle-income countries.

  1. Automatic initialization and quality control of large-scale cardiac MRI segmentations.

    Science.gov (United States)

    Albà, Xènia; Lekadir, Karim; Pereañez, Marco; Medrano-Gracia, Pau; Young, Alistair A; Frangi, Alejandro F

    2017-10-16

    Continuous advances in imaging technologies enable ever more comprehensive phenotyping of human anatomy and physiology. Concomitant reduction of imaging costs has resulted in widespread use of imaging in large clinical trials and population imaging studies. Magnetic Resonance Imaging (MRI), in particular, offers one-stop-shop multidimensional biomarkers of cardiovascular physiology and pathology. A wide range of analysis methods offer sophisticated cardiac image assessment and quantification for clinical and research studies. However, most methods have only been evaluated on relatively small databases often not accessible for open and fair benchmarking. Consequently, published performance indices are not directly comparable across studies and their translation and scalability to large clinical trials or population imaging cohorts is uncertain. Most existing techniques still rely on considerable manual intervention for the initialization and quality control of the segmentation process, becoming prohibitive when dealing with thousands of images. The contributions of this paper are three-fold. First, we propose a fully automatic method for initializing cardiac MRI segmentation, by using image features and random forests regression to predict an initial position of the heart and key anatomical landmarks in an MRI volume. In processing a full imaging database, the technique predicts the optimal corrective displacements and positions in relation to the initial rough intersections of the long and short axis images. Second, we introduce for the first time a quality control measure capable of identifying incorrect cardiac segmentations with no visual assessment. The method uses statistical, pattern and fractal descriptors in a random forest classifier to detect failures to be corrected or removed from subsequent statistical analysis. Finally, we validate these new techniques within a full pipeline for cardiac segmentation applicable to large-scale cardiac MRI databases. The

  2. FULL-SCALE TESTING OF ENHANCED MERCURY CONTROL TECHNOLOGIES FOR WET FGD SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    D.K. McDonald; G.T. Amrhein; G.A. Kudlac; D. Madden Yurchison

    2003-05-07

    Wet flue gas desulfurization (wet FGD) systems are currently installed on about 25% of the coal-fired utility generating capacity in the U.S., representing about 15% of the number of coal-fired units. Depending on the effect of operating parameters such as mercury content of the coal, form of mercury (elemental or oxidized) in the flue gas, scrubber spray tower configuration, liquid-to-gas ratio, and slurry chemistry, FGD systems can provide cost-effective, near-term mercury emissions control options with a proven history of commercial operation. For boilers already equipped with FGD systems, the incremental cost of any vapor phase mercury removal achieved is minimal. To be widely accepted and implemented, technical approaches that improve mercury removal performance for wet FGD systems should also have low incremental costs and have little or no impact on operation and SO{sub 2} removal performance. The ultimate goal of the Full-scale Testing of Enhanced Mercury Control for Wet FGD Systems Program was to commercialize methods for the control of mercury in coal-fired electric utility systems equipped with wet flue gas desulfurization (wet FGD). The program was funded by the U.S. Department of Energy's National Energy Technology Laboratory, the Ohio Coal Development Office within the Ohio Department of Development, and Babcock & Wilcox. Host sites and associated support were provided by Michigan South Central Power Agency (MSCPA) and Cinergy. Field-testing was completed at two commercial coal-fired utilities with wet FGD systems: (1) MSCPA's 55 MW{sub e} Endicott Station and (2) Cinergy's 1300 MW{sub e} Zimmer Station. Testing was conducted at these two locations because of the large differences in size and wet scrubber chemistry. Endicott employs a limestone, forced oxidation (LSFO) wet FGD system, whereas Zimmer uses Thiosorbic{reg_sign} Lime (magnesium enhanced lime) and ex situ oxidation. Both locations burn Ohio bituminous coal.

  3. Scale dependent controls of stream water temperatures - interaction of advective and diffusive energy fluxes

    Science.gov (United States)

    Schuetz, Tobias; Weiler, Markus

    2017-04-01

    fluxes were estimated with a sine curve model (amplitude of 300 W/m2, which includes all relevant fluxes by definition). For specific types of rivers we can clearly determine the scale transformation of WTA from being dominated by upstream processes (advective energy transport via surface discharges) to local processes (local energy budget and groundwater dependent processes). Moreover, we found for scales of 10 km and larger that WTAs can be locally more or less completely dampened out by the overlay of advective and local diffusive fluxes. Up to date this process has not been mentioned in the literature due to the lack of necessary temporal and/or spatial resolution of water quality monitoring stations. These findings shed new light on our understanding of the controls of locally observable water temperatures and should be considered for water quality management and stream ecology, e.g. for the planning of water quality monitoring stations or river restorations.

  4. Effectiveness of a controlled release chlorhexidine chip (PerioCol™-CG) as an adjunctive to scaling and root planing when compared to scaling and root planing alone in the treatment of chronic periodontitis: A comparative study

    National Research Council Canada - National Science Library

    Kondreddy, Kameswari; Ambalavanan, N; Ramakrishna, T; Kumar, R Saravana

    2012-01-01

    The aim of this study is to evaluate the effectiveness of a controlled-release chlorhexidine chip as an adjunctive therapy to scaling and root planing when compared with scaling and root planing alone...

  5. Kinetically controlled synthesis of large-scale morphology-tailored silver nanostructures at low temperature

    Science.gov (United States)

    Zhang, Ling; Zhao, Yuda; Lin, Ziyuan; Gu, Fangyuan; Lau, Shu Ping; Li, Li; Chai, Yang

    2015-08-01

    Ag nanostructures are widely used in catalysis, energy conversion and chemical sensing. Morphology-tailored synthesis of Ag nanostructures is critical to tune physical and chemical properties. In this study, we develop a method for synthesizing the morphology-tailored Ag nanostructures in aqueous solution at a low temperature (45 °C). With the use of AgCl nanoparticles as the precursor, the growth kinetics of Ag nanostructures can be tuned with the pH value of solution and the concentration of Pd cubes which catalyze the reaction. Ascorbic acid and cetylpyridinium chloride are used as the mild reducing agent and capping agent in aqueous solution, respectively. High-yield Ag nanocubes, nanowires, right triangular bipyramids/cubes with twinned boundaries, and decahedra are successfully produced. Our method opens up a new environmentally-friendly and economical route to synthesize large-scale and morphology-tailored Ag nanostructures, which is significant to the controllable fabrication of Ag nanostructures and fundamental understanding of the growth kinetics.Ag nanostructures are widely used in catalysis, energy conversion and chemical sensing. Morphology-tailored synthesis of Ag nanostructures is critical to tune physical and chemical properties. In this study, we develop a method for synthesizing the morphology-tailored Ag nanostructures in aqueous solution at a low temperature (45 °C). With the use of AgCl nanoparticles as the precursor, the growth kinetics of Ag nanostructures can be tuned with the pH value of solution and the concentration of Pd cubes which catalyze the reaction. Ascorbic acid and cetylpyridinium chloride are used as the mild reducing agent and capping agent in aqueous solution, respectively. High-yield Ag nanocubes, nanowires, right triangular bipyramids/cubes with twinned boundaries, and decahedra are successfully produced. Our method opens up a new environmentally-friendly and economical route to synthesize large-scale and morphology

  6. A novel method for fuzzy scale factors scheduling in fuzzy PD+I with anti-windup system controllers

    Directory of Open Access Journals (Sweden)

    Aldo Rafael Sartorius-Castellanos

    2016-01-01

    Full Text Available The adjustment of scale factors in fuzzy controllers is a key factor in their correct functioning. In two-inputs fuzzy PID controllers, such as fuzzy PI+D (FPI+D and fuzzy PD+I (FPD+I, the adjustment of scale factors is directly related to the adjustment of the gains of a PID controller using some of the traditional methods of adjustment. In systems that have control signal saturation, fuzzy PID controllers require anti-windup systems (AW that limit the controller’s integral action. In these situations, the adjustments of scale factors are not directly related to the adjustment of gains of a PID controller. Its use increases the overall gain system and creates an unbounded controller, which causes a faster response in the transient state but an oscillatory behavior and even critical stability in the steady state of the response. A solution to this problem is to reduce the output scale factor, to create a bounded controller, in which the tracking time constant is augmented. Consequently, the system presents more bounded oscillations in the steady state, but the transient response is slower. The main motivation of this research was to develop an approach for adjusting fuzzy PD+I controllers with an anti-windup system (FPD+I AW with faster response in the transient state and without oscillatory behavior in the steady state. This approach uses a second fuzzy controller, which adjusts the output scale factor and the tracking time constant according to the actual system error. To verify the effectiveness of the proposed approach, a fuzzy PD+I controller with an AW system based on tracking back calculation and fuzzy scale factor scheduling (FPD+I AW-FSFS was implemented and used to control the speed in a direct current motor with control signal saturation and was compared with the responses of FPD+I unbounded and FPD+I bounded controllers with AWs based on tracking back calculation, thereby proving the effectiveness of the proposed method.

  7. Scalable multi-objective control for large scale water resources systems under uncertainty

    Science.gov (United States)

    Giuliani, Matteo; Quinn, Julianne; Herman, Jonathan; Castelletti, Andrea; Reed, Patrick

    2016-04-01

    The use of mathematical models to support the optimal management of environmental systems is rapidly expanding over the last years due to advances in scientific knowledge of the natural processes, efficiency of the optimization techniques, and availability of computational resources. However, undergoing changes in climate and society introduce additional challenges for controlling these systems, ultimately motivating the emergence of complex models to explore key causal relationships and dependencies on uncontrolled sources of variability. In this work, we contribute a novel implementation of the evolutionary multi-objective direct policy search (EMODPS) method for controlling environmental systems under uncertainty. The proposed approach combines direct policy search (DPS) with hierarchical parallelization of multi-objective evolutionary algorithms (MOEAs) and offers a threefold advantage: the DPS simulation-based optimization can be combined with any simulation model and does not add any constraint on modeled information, allowing the use of exogenous information in conditioning the decisions. Moreover, the combination of DPS and MOEAs prompts the generation or Pareto approximate set of solutions for up to 10 objectives, thus overcoming the decision biases produced by cognitive myopia, where narrow or restrictive definitions of optimality strongly limit the discovery of decision relevant alternatives. Finally, the use of large-scale MOEAs parallelization improves the ability of the designed solutions in handling the uncertainty due to severe natural variability. The proposed approach is demonstrated on a challenging water resources management problem represented by the optimal control of a network of four multipurpose water reservoirs in the Red River basin (Vietnam). As part of the medium-long term energy and food security national strategy, four large reservoirs have been constructed on the Red River tributaries, which are mainly operated for hydropower

  8. Biocrust spatial distribution at landscape scale is strongly controlled by terrain attributes: Topographic thresholds for colonization

    Science.gov (United States)

    Raúl Román Fernández, José; Rodríguez-Caballero, Emilio; Chamizo de la Piedra, Sonia; Roncero Ramos, Bea; Cantón Castilla, Yolanda

    2017-04-01

    Biological soil crusts (biocrusts) are spatially variable components of soil. Whereas biogeographic, climatic or soil properties drive biocrust distribution from regional to global scales, biocrust spatial distribution within the landscape is controlled by topographic forces that create specific microhabitats that promote or difficult biocrust growth. By knowing which are the variables that control biocrust distribution and their individual effect we can establish the abiotic thresholds that limit natural biocrust colonization on different environments, which may be very useful for designing soil restoration programmes. The objective of this study was to analyse the influence of topographic-related variables in the distribution of different types of biocrust within a semiarid catchment where cyanobacteria and lichen dominated biocrust represent the most important surface components, El Cautivo experimental area (SE Spain). To do this, natural coverage of i) bare soil, ii) vegetation, iii) cyanobacteria-dominated soil crust and iv) lichen-dominated soil crust were measured on 70 experimental plots distributed across 23 transect (three 4.5 x 4.5 m plots per transect). Following that, we used a 1m x 1m DEM (Digital Elevation Model) of the study site obtained from a LiDAR point cloud to calculate different topographic variables such as slope gradient, length slope (LS) factor (potential sediment transport index), potential incoming solar radiation, topographic wetness index (WI) and maximum flow accumulation. Canonical Correspondence Analysis was performed to infer the influence of each variable in the coverage of each class and thresholds of biocrust colonization were identified mathematically by means of linear regression analysis describing the relationship between each factor and biocrust cover. Our results show that the spatial distribution of cyanobacteria-dominated biocrust, which showed physiological and morphological adaptation to cope with drought and UVA

  9. Security, protection, and control of power systems with large-scale wind power penetration

    Science.gov (United States)

    Acharya, Naresh

    As the number of wind generation facilities in the utility system is fast increasing, many issues associated with their integration into the power system are beginning to emerge. Of the various issues, this dissertation deals with the development of new concepts and computational methods to handle the transmission issues and voltage issues caused by large-scale integration of wind turbines. This dissertation also formulates a probabilistic framework for the steady-state security assessment of wind power incorporating the forecast uncertainty and correlation. Transmission issues are mainly related to the overloading of transmission lines, when all the wind power generated cannot be delivered in full due to prior outage conditions. To deal with this problem, a method to curtail the wind turbine outputs through Energy Management System facilities in the on-line operational environment is proposed. The proposed method, which is based on linear optimization, sends the calculated control signals via the Supervisory Control and Data Acquisition system to wind farm controllers. The necessary ramping of the wind farm outputs is implemented either by the appropriate blade pitch angle control at the turbine level or by switching a certain number of turbines. The curtailment strategy is tested with an equivalent system model of MidAmerican Energy Company. The results show that the line overload in high wind areas can be alleviated by controlling the outputs of the wind farms step-by-step over an allowable period of time. A low voltage event during a system fault can cause a large number of wind turbines to trip, depending on voltages at the wind turbine terminals during the fault and the under-voltage protection setting of wind turbines. As a result, an N-1 contingency may evolve into an N-(K+1) contingency, where K is the number of wind farms tripped due to low voltage conditions. Losing a large amount of wind power following a line contingency might lead to system

  10. All-optical control of electron self-injection in millimeter-scale, tapered dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Kalmykov, S.Y., E-mail: serguei.kalmykov@yahoo.com [Department of Physics and Astronomy, University of Nebraska—Lincoln, Lincoln, NE 68588-0299 (United States); Davoine, X. [CEA, DAM, DIF, Arpajon F-91297 (France); Shadwick, B.A. [Department of Physics and Astronomy, University of Nebraska—Lincoln, Lincoln, NE 68588-0299 (United States)

    2014-03-11

    It is demonstrated that a laser pulse with an ultrahigh bandwidth (Δλ∼400 nm) is an asset for future high-repetition-rate, quasimonoenergetic (QME), GeV-scale laser plasma electron accelerators. Manipulating the phase of the driver has a direct impact on evolution of the accelerating bucket (a cavity of electron density maintained by the pressure of the laser pulse radiation), making it possible to control electron self-injection and the final parameters of the QME beam by purely optical means. The large bandwidth makes it possible to compensate for the frequency red-shift accumulated at the pulse leading edge in transit through the plasma. Advancing higher frequencies in time (viz. introducing a negative frequency chirp of the incident pulse) reduces the red-shift, preventing self-compression of the pulse into a relativistic optical shock. This avoids constant expansion of the plasma bucket, suppressing continuous self-injection of copious unwanted electrons, keeping the beam almost free of a high-charge, poorly collimated low-energy tail. In addition, gradually increasing the plasma density in the forward direction locks electrons in the accelerating phase, delaying their dephasing and boosting their energy without increasing the tail. Advantages of this technique are demonstrated here for acceleration in sub-millimeter-length, dense plasmas (n{sub 0}>10{sup 19}cm{sup −3}), using 100-mJ-scale energy laser pulses. Three-dimensional particle-in-cell simulations show that a negatively chirped, 15 TW pulse with a 20 fs length and a bandwidth corresponding to a transform-limited duration below two optical cycles, in combination with a modest density taper (corresponding to 25% linear increase of the density in the forward direction), transfers 3.5% of its energy to a 300 MeV electron bunch with relative energy spread below 4% and flux a factor 4.5 higher than the average flux in the tail. The acceleration occurs over a 0.6 mm plasma with the electron density at

  11. A real-time control method-based simulation for high-speed trains on large-scale rail network

    Science.gov (United States)

    Liu, Yutong; Cao, Chengxuan; Zhou, Yaling; Feng, Ziyan

    In this paper, an improved real-time control model based on the discrete-time method is constructed to control and simulate the movement of high-speed trains on large-scale rail network. The constraints of acceleration and deceleration are introduced in this model, and a more reasonable definition of the minimal headway is also presented. Considering the complicated rail traffic environment in practice, we propose a set of sound operational strategies to excellently control traffic flow on rail network under various conditions. Several simulation experiments with different parameter combinations are conducted to verify the effectiveness of the control simulation method. The experimental results are similar to realistic environment and some characteristics of rail traffic flow are also investigated, especially the impact of stochastic disturbances and the minimal headway on the rail traffic flow on large-scale rail network, which can better assist dispatchers in analysis and decision-making. Meanwhile, experimental results also demonstrate that the proposed control simulation method can be in real-time control of traffic flow for high-speed trains not only on the simple rail line, but also on the complicated large-scale network such as China’s high-speed rail network and serve as a tool of simulating the traffic flow on large-scale rail network to study the characteristics of rail traffic flow.

  12. Synthetically chemical-electrical mechanism for controlling large scale reversible deformation of liquid metal objects

    Science.gov (United States)

    Zhang, Jie; Sheng, Lei; Liu, Jing

    2014-11-01

    Reversible deformation of a machine holds enormous promise across many scientific areas ranging from mechanical engineering to applied physics. So far, such capabilities are still hard to achieve through conventional rigid materials or depending mainly on elastomeric materials, which however own rather limited performances and require complicated manipulations. Here, we show a basic strategy which is fundamentally different from the existing ones to realize large scale reversible deformation through controlling the working materials via the synthetically chemical-electrical mechanism (SCHEME). Such activity incorporates an object of liquid metal gallium whose surface area could spread up to five times of its original size and vice versa under low energy consumption. Particularly, the alterable surface tension based on combination of chemical dissolution and electrochemical oxidation is ascribed to the reversible shape transformation, which works much more flexible than many former deformation principles through converting electrical energy into mechanical movement. A series of very unusual phenomena regarding the reversible configurational shifts are disclosed with dominant factors clarified. This study opens a generalized way to combine the liquid metal serving as shape-variable element with the SCHEME to compose functional soft machines, which implies huge potential for developing future smart robots to fulfill various complicated tasks.

  13. Time lags in watershed-scale nutrient transport: an exploration of dominant controls

    Science.gov (United States)

    Van Meter, K. J.; Basu, N. B.

    2017-08-01

    Unprecedented decreases in atmospheric nitrogen (N) deposition together with increases in agricultural N-use efficiency have led to decreases in net anthropogenic N inputs in many eastern US and Canadian watersheds as well as in Europe. Despite such decreases, N concentrations in streams and rivers continue to increase, and problems of coastal eutrophication remain acute. Such a mismatch between N inputs and outputs can arise due to legacy N accumulation and subsequent lag times between implementation of conservation measures and improvements in water quality. In the present study, we quantified such lag times by pairing long-term N input trajectories with stream nitrate concentration data for 16 nested subwatersheds in a 6800 km2, Southern Ontario watershed. Our results show significant nonlinearity between N inputs and outputs, with a strong hysteresis effect indicative of decadal-scale lag times. The mean annual lag time was found to be 24.5 years, with lags varying seasonally, likely due to differences in N-delivery pathways. Lag times were found to be negatively correlated with both tile drainage and watershed slope, with tile drainage being a dominant control in fall and watershed slope being significant during the spring snowmelt period. Quantification of such lags will be crucial to policy-makers as they struggle to set appropriate goals for water quality improvement in human-impacted watersheds.

  14. Synthetically chemical-electrical mechanism for controlling large scale reversible deformation of liquid metal objects.

    Science.gov (United States)

    Zhang, Jie; Sheng, Lei; Liu, Jing

    2014-11-19

    Reversible deformation of a machine holds enormous promise across many scientific areas ranging from mechanical engineering to applied physics. So far, such capabilities are still hard to achieve through conventional rigid materials or depending mainly on elastomeric materials, which however own rather limited performances and require complicated manipulations. Here, we show a basic strategy which is fundamentally different from the existing ones to realize large scale reversible deformation through controlling the working materials via the synthetically chemical-electrical mechanism (SCHEME). Such activity incorporates an object of liquid metal gallium whose surface area could spread up to five times of its original size and vice versa under low energy consumption. Particularly, the alterable surface tension based on combination of chemical dissolution and electrochemical oxidation is ascribed to the reversible shape transformation, which works much more flexible than many former deformation principles through converting electrical energy into mechanical movement. A series of very unusual phenomena regarding the reversible configurational shifts are disclosed with dominant factors clarified. This study opens a generalized way to combine the liquid metal serving as shape-variable element with the SCHEME to compose functional soft machines, which implies huge potential for developing future smart robots to fulfill various complicated tasks.

  15. Translation of the Multidimensional Health Locus of Control Scales for Users of American Sign Language

    Science.gov (United States)

    Samady, Waheeda; Sadler, Georgia Robins; Nakaji, Melanie; Malcarne, Vanessa L.; Trybus, Raymond; Athale, Ninad

    2008-01-01

    This paper describes the translation of the Multidimensional Health Locus of Control (MHLC) scales into American Sign Language (ASL). Translation is an essential first step toward validating the instrument for use in the Deaf community, a commonly overlooked minority community. This translated MHLC/ASL can be utilized by public health nurses researching the Deaf community to create and evaluate targeted health interventions. It can be used in clinical settings to guide the context of the provider-patient dialogue. The MHLC was translated using focus groups, following recommended procedures. Five bilingual participants translated the MHLC into ASL; five others back-translated the ASL version into English. Both focus groups identified and addressed language and cultural problems before the final ASL version of the MHLC was permanently captured on by motion picture photography for consistent administration. Nine of the 24 items were directly translatable into ASL. The remaining items required further discussion to achieve cultural equivalence with ASL expressions. The MHLC/ASL is now ready for validation within the Deaf community. PMID:18816365

  16. Translation of the multidimensional health locus of control scales for users of American sign language.

    Science.gov (United States)

    Samady, Waheeda; Samady, Waheedy; Sadler, Georgia Robins; Nakaji, Melanie; Malcarne, Vanessa L; Trybus, Raymond; Athale, Ninad

    2008-01-01

    This paper describes the translation of the Multidimensional Health Locus of Control (MHLC) scales into American Sign Language (ASL). Translation is an essential first step toward validating the instrument for use in the Deaf community, a commonly overlooked minority community. This translated MHLC/ASL can be utilized by public health nurses researching the Deaf community to create and evaluate targeted health interventions. It can be used in clinical settings to guide the context of the provider-patient dialogue. The MHLC was translated using focus groups, following recommended procedures. 5 bilingual participants translated the MHLC into ASL; 5 others back-translated the ASL version into English. Both focus groups identified and addressed language and cultural problems before the final ASL version of the MHLC was permanently captured by motion picture photography for consistent administration. Nine of the 24 items were directly translatable into ASL. The remaining items required further discussion to achieve cultural equivalence with ASL expressions. The MHLC/ASL is now ready for validation within the Deaf community.

  17. DEVELOPMENT OF CONTROLLED PITCH NANO ARRAYS FOR APPLICATION IN NANO SCALE BASED PROPORTIONAL COUNTERS

    Energy Technology Data Exchange (ETDEWEB)

    Sexton, L.; Serkiz, S.; Siegfried, M.

    2010-06-07

    Proportional counters (PCs) are a type of gas-filled radiation detection device capable of distinguishing between a wide range of radiation types and energies. In this application, however, these devices are limited by high power consumption and high bias potentials required to operate in the proportional detection regime. Previous work performed with a single carbon nanotube (CNT) anode has shown that nanoscale-based PCs can operate at bias potentials of 10V rather than the 1000V range required for PCs. ''Proof of concept'' experiments with a single CNT as the anode exhibit a small detection volume and consequently required long count times (24 hrs). To make this a practical detector technology (i.e., decrease the count time), the effective detection volume has to be increased. Experimental data and electric field modeling show that if the pitch (spacing between individual nanotubes) of the arrays is too small, the electric field of the individual nanostructure will collapse and the nanoscale array will behaved as a single macro-scale field with the associated high bias potential required to reach the proportional region. Electric-field modeling of the affect of nanostructure pitch on the electric field distribution of these arrays predicted that a pitch of about two-and-a-times the height of the nanostructure was required to retain the nanoscale electric field. In this work, we report on the fabrication and electrical property testing of nanoscale arrays with a range of controlled pitches.

  18. Glycohemoglobin assays evaluated in a large-scale quality-control survey.

    Science.gov (United States)

    Gillery, P; Labbé, D; Dumont, G; Vassault, A

    1995-11-01

    We report the results of a national quality-control survey on glycohemoglobin (GHb), monitored in France by the Société Française de Biologie Clinique on behalf of the authority of the "Agence du Médicament." A sample of lyophilized hemolysate was sent to 3109 laboratories. Results were obtained from 2770 laboratories. HbA1C, HbA1, and total GHb were measured by 50%, 24%, and 26% of the participants, respectively. Of these measurements, 79% of the HbA1C results and 76% of the total GHb results, but only 48% of the HbA1 results, were within the +/- 20% limits of the indicated target values. Mean values for the hemolysate ranged from 8% to 11% for HbA1C, from 7% to 12% for HbA1, and from 11% to 13% for total GHb. The interlaboratory CVs ranged from 3% to 20%, according to method used. So, methods used for GHb assay, which are based on various principles, exhibit very different analytical performances. Nonetheless, this large-scale study indicates that some techniques can support transferability of results from laboratory to laboratory.

  19. ARRA-Multi-Level Energy Storage and Controls for Large-Scale Wind Energy Integration

    Energy Technology Data Exchange (ETDEWEB)

    David Wenzhong Gao

    2012-09-30

    intelligent controller that increases battery life within hybrid energy storage systems for wind application was developed. Comprehensive studies have been conducted and simulation results are analyzed. A permanent magnet synchronous generator, coupled with a variable speed wind turbine, is connected to a power grid (14-bus system). A rectifier, a DC-DC converter and an inverter are used to provide a complete model of the wind system. An Energy Storage System (ESS) is connected to a DC-link through a DC-DC converter. An intelligent controller is applied to the DC-DC converter to help the Voltage Source Inverter (VSI) to regulate output power and also to control the operation of the battery and supercapacitor. This ensures a longer life time for the batteries. The detailed model is simulated in PSCAD/EMTP. Additionally, economic analysis has been done for different methods that can reduce the wind power output fluctuation. These methods are, wind power curtailment, dumping loads, battery energy storage system and hybrid energy storage system. From the results, application of single advanced HESS can save more money for wind turbines owners. Generally the income would be the same for most of methods because the wind does not change and maximum power point tracking can be applied to most systems. On the other hand, the cost is the key point. For short term and small wind turbine, the BESS is the cheapest and applicable method while for large scale wind turbines and wind farms the application of advanced HESS would be the best method to reduce the power fluctuation. The key outcomes of this project include a new intelligent controller that can reduce energy exchanged between the battery and DC-link, reduce charging/discharging cycles, reduce depth of discharge and increase time interval between charge/discharge, and lower battery temperature. This improves the overall lifetime of battery energy storages. Additionally, a new design method based on probability help optimize the

  20. Reliability and Validity of the Multidimensional Locus of Control IPC Scale in a Sample of 3668 Greek Educators

    Directory of Open Access Journals (Sweden)

    Ntina Kourmousi

    2015-11-01

    Full Text Available The Multidimensional Locus of Control IPC Scale (IPC LOC Scale is an instrument for assessing the locus of control on adults. The aim of the present study is to translate the IPC LOC Scale and evaluate its reliability and validity in a sample of Greek teachers. Data were collected from a nationwide sample of 3668 educators of all levels and specialties. The Cronbach’s alpha coefficient was used to determine the internal consistency reliability. A confirmatory factor analysis (CFA was conducted in order to test the construct validity of the questionnaire. Validity was further examined by investigating the correlation of the IPC LOC Scale with the Rosenberg self-esteem scale (RSES and its association with several demographic and work-related data. Internal consistency reliability was satisfactory with a Cronbach’s alpha above 0.70 for all LOC dimensions. CFA confirmed that the items composing the three subscales of the IPC LOC Scale measure the same construct. Also, the root mean square error of approximation (RMSEA, the comparative fit index (CFI and the goodness of fit index (GFI values were 0.053, 0.951, and 0.937, respectively for the three-factor model, further confirming the manufacturer’s theory for the three latent variables, Internality, Powerful Others, and Chance. Intercorrelations and correlation coefficients between the IPC LOC Scale and the RSES were significant, while age and sex differences were also found. The Greek version of the IPC LOC Scale was found to have satisfactory psychometric properties and could be used to evaluate the locus of control in Greek teachers.

  1. Interpretation of response categories in patient-reported rating scales: a controlled study among people with Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Knutsson Ida

    2010-06-01

    Full Text Available Abstract Background Unambiguous interpretation of ordered rating scale response categories requires distinct meanings of category labels. Also, summation of item responses into total scores assumes equal intervals between categories. While studies have identified problems with rating scale response category functioning there is a paucity of empirical studies regarding how respondents interpret response categories. We investigated the interpretation of commonly used rating scale response categories and attempted to identify distinct and roughly equally spaced response categories for patient-reported rating scales in Parkinson's disease (PD and age-matched control subjects. Methods Twenty-one rating scale response categories representing frequency, intensity and level of agreement were presented in random order to 51 people with PD (36 men; mean age, 66 years and 36 age-matched controls (14 men; mean age, 66. Respondents indicated their interpretation of each category on 100-mm visual analog scales (VAS anchored by Never - Always, Not at all - Extremely, and Totally disagree - Completely agree. VAS values were compared between groups, and response categories with mean values and non-overlapping 95% CIs corresponding to equally spaced locations on the VAS line were sought to identify the best options for three-, four-, five-, and six-category scales. Results VAS values did not differ between the PD and control samples (P = 0.286 or according to educational level (P = 0.220, age (P = 0.220, self-reported physical functioning (P = 0.501 and mental health (P = 0.238, or (for the PD sample PD duration (P = 0.213 or presence of dyskinesias (P = 0.212. Attempts to identify roughly equally spaced response categories for three-, four-, five-, and six-category scales were unsuccessful, as the 95% CIs of one or several of the identified response categories failed to include the criterion values for equal distances. Conclusions This study offers an evidence

  2. Pilot-scale application of an online VFA sensor for monitoring and control of a manure digester

    DEFF Research Database (Denmark)

    Boe, Kanokwan; Angelidaki, Irini

    2012-01-01

    A volatile fatty acids (VFA) sensor based on headspace chromatography was tested for online monitoring and control of a pilot-scale manure digester. The sensor showed satisfying results in terms of sensitivity and reliability for monitoring of the digester. The online VFA and biogas production data...... were used for automatic control of the digester based on feed flow manipulation. The control approach was based on optimization of biogas production while using VFA concentration as the alarm threshold. A rule-based supervisory system with a cascade controller was used to optimize the biogas production...

  3. In-Flight Validation of a Pilot Rating Scale for Evaluating Failure Transients in Electronic Flight Control Systems

    Science.gov (United States)

    Kalinowski, Kevin F.; Tucker, George E.; Moralez, Ernesto, III

    2006-01-01

    Engineering development and qualification of a Research Flight Control System (RFCS) for the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) JUH-60A has motivated the development of a pilot rating scale for evaluating failure transients in fly-by-wire flight control systems. The RASCAL RFCS includes a highly-reliable, dual-channel Servo Control Unit (SCU) to command and monitor the performance of the fly-by-wire actuators and protect against the effects of erroneous commands from the flexible, but single-thread Flight Control Computer. During the design phase of the RFCS, two piloted simulations were conducted on the Ames Research Center Vertical Motion Simulator (VMS) to help define the required performance characteristics of the safety monitoring algorithms in the SCU. Simulated failures, including hard-over and slow-over commands, were injected into the command path, and the aircraft response and safety monitor performance were evaluated. A subjective Failure/Recovery Rating (F/RR) scale was developed as a means of quantifying the effects of the injected failures on the aircraft state and the degree of pilot effort required to safely recover the aircraft. A brief evaluation of the rating scale was also conducted on the Army/NASA CH-47B variable stability helicopter to confirm that the rating scale was likely to be equally applicable to in-flight evaluations. Following the initial research flight qualification of the RFCS in 2002, a flight test effort was begun to validate the performance of the safety monitors and to validate their design for the safe conduct of research flight testing. Simulated failures were injected into the SCU, and the F/RR scale was applied to assess the results. The results validate the performance of the monitors, and indicate that the Failure/Recovery Rating scale is a very useful tool for evaluating failure transients in fly-by-wire flight control systems.

  4. Multicontroller: an object programming approach to introduce advanced control algorithms for the GCS large scale project

    CERN Document Server

    Cabaret, S; Coppier, H; Rachid, A; Barillère, R; CERN. Geneva. IT Department

    2007-01-01

    The GCS (Gas Control System) project team at CERN uses a Model Driven Approach with a Framework - UNICOS (UNified Industrial COntrol System) - based on PLC (Programming Language Controller) and SCADA (Supervisory Control And Data Acquisition) technologies. The first' UNICOS versions were able to provide a PID (Proportional Integrative Derivative) controller whereas the Gas Systems required more advanced control strategies. The MultiController is a new UNICOS object which provides the following advanced control algorithms: Smith Predictor, PFC (Predictive Function Control), RST* and GPC (Global Predictive Control). Its design is based on a monolithic entity with a global structure definition which is able to capture the desired set of parameters of any specific control algorithm supported by the object. The SCADA system -- PVSS - supervises the MultiController operation. The PVSS interface provides users with supervision faceplate, in particular it links any MultiController with recipes: the GCS experts are ab...

  5. Fouling control in a lab-scale MBR system: Comparison of several commercially applied coagulants.

    Science.gov (United States)

    Gkotsis, P K; Batsari, E L; Peleka, E N; Tolkou, A K; Zouboulis, A I

    2017-12-01

    The Membrane bioreactors (MBRs) integrate the biological degradation of pollutants with membrane filtration-separation during wastewater treatment. Membrane fouling, which is considered as the main process drawback, stems from the interaction between the membrane material and the (organic or inorganic) foulants, leading to membrane's efficiency deterioration. It is widely recognized that the mixed liquor colloidal and Soluble Microbial Products (SMP) are in principal responsible for this undesirable situation. As a result, the appropriate pretreatment of wastewater feed is often considered as necessary procedure and the coagulation/flocculation (C/F) process is regarded as a relevant viable option for wastewater treatment by MBRs in order to improve the effective removal of suspended solids (SS), of colloidal particles, of natural organic matter (NOM), as well as of other soluble materials. The objective of this study is the application of coagulation/flocculation for fouling control of MBR systems by using several commercially available chemical coagulant/flocculant agents. For this purpose, an appropriate lab-scale continuous-flow, fully automatic MBR system has been assembled and various (inorganic) coagulants (i.e. FeCl3∙6H2O, Fe2(SO4)3·5H2O, FeClSO4, PFS0.3, PAC A9-M, PAC-A16, Al2(SO4)3·18H2O, FO4350SSH, NaAlO2) have been examined. Filterability tests and SMP concentration measurements were also conducted in order to investigate the reversible, as well as the irreversible fouling, respectively. Based upon the obtained results and after selecting the most efficient coagulants (FeCl3·6H2O, Fe2(SO4)3·5H2O, FeClSO4, PAC-A9, PAC-A16), an attempt was subsequently performed to correlate the major fouling indices (i.e. TMP, TTF, SMP concentration) in order to improve the overall process operability by this fouling control method. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Watershed Controls on the Proper Scale of Economic Markets for Pollution Reduction

    Science.gov (United States)

    Rigby, J.; Doyle, M. W.; Yates, A.

    2010-12-01

    Markets for tradable discharge permits (TDPs) are an increasingly popular policy instrument for obtaining cost-effective nutrient reduction targets across watersheds. Such markets are also an emerging, dynamic coupling between economic institutions and stream hydrology/biogeochemistry as trading markets become explicit determinants for the spatial distribution of stream nutrient loads. A central problem in any environmental market program is setting the size of the market, as there are distinct trade-offs for large versus small markets. While the overall cost-effectiveness of permit trading increases with the size of the market, the potential for localized and highly damaging nutrient concentrations, or “hotspots”, also increases. Smaller market size reduces the potential for hot spots by dispersing the location of trades, but this may increase the net costs of water quality compliance significantly through both the restriction of possible trading partners and price manipulation by market participants. This project couples a microeconomic model for TDPs (based on possible configurations of mutually exclusive trading zones within the basin) with a semi-distributed water quality model to examine watershed controls on the configuration and scale of such markets. Our results show a wide variation in total annual cost of pollution abatement based on choice of market design -- often with large differences in cost between very similar configurations. This framework is also applied to a 10-member trading program among wastewater treatment plants in the Neuse River, NC, in order to assess (1) the optimum market design for the Upper Neuse basin and (2) how these costs compare with expected costs under alternative market structures (e.g., trading ratio system) and (3) the cost improvements over traditional command-and-control regulatory frameworks. We find that the optimal zone configuration is almost always a lower cost option when compared to a trading ratio scheme and

  7. Large-scale self-assembly of uniform submicron silver sulfide material driven by precise pressure control

    Science.gov (United States)

    Qi, Juanjuan; Chen, Ke; Zhang, Shuhao; Yang, Yun; Guo, Lin; Yang, Shihe

    2017-03-01

    The controllable self-assembly of nanosized building blocks into larger specific structures can provide an efficient method of synthesizing novel materials with excellent properties. The self-assembly of nanocrystals by assisted means is becoming an extremely active area of research, because it provides a method of producing large-scale advanced functional materials with potential applications in the areas of energy, electronics, optics, and biologics. In this study, we applied an efficient strategy, namely, the use of ‘pressure control’ to the assembly of silver sulfide (Ag2S) nanospheres with a diameter of approximately 33 nm into large-scale, uniform Ag2S sub-microspheres with a size of about 0.33 μm. More importantly, this strategy realizes the online control of the overall reaction system, including the pressure, reaction time, and temperature, and could also be used to easily fabricate other functional materials on an industrial scale. Moreover, the thermodynamics and kinetics parameters for the thermal decomposition of silver diethyldithiocarbamate (Ag(DDTC)) are also investigated to explore the formation mechanism of the Ag2S nanosized building blocks which can be assembled into uniform sub-micron scale architecture. As a method of producing sub-micron Ag2S particles by means of the pressure-controlled self-assembly of nanoparticles, we foresee this strategy being an efficient and universally applicable option for constructing other new building blocks and assembling novel and large functional micromaterials on an industrial scale.

  8. Robust Nonfragile Controllers Design for Fractional Order Large-Scale Uncertain Systems with a Commensurate Order 1<α<2

    Directory of Open Access Journals (Sweden)

    Jianyu Lin

    2015-01-01

    uncertain systems with a commensurate order 1<α<2 under controller gain uncertainties. The uncertainties are of norm-bounded type. Based on the stability criterion of fractional order system, sufficient conditions on the decentralized stabilization of fractional order large-scale uncertain systems in both cases of additive and multiplicative gain perturbations are established by using the complex Lyapunov inequality. Moreover, the decentralized nonfragile controllers are designed. Finally, some numerical examples are given to validate the proposed method.

  9. Mindful Creativity Scale (MCS): Validation of a German version of the Langer Mindfulness Scale with patients with severe TBI and controls.

    Science.gov (United States)

    Haller, Chiara S

    2015-01-01

    Mindfulness may have an impact on the recovery process in patients who have suffered severe traumatic brain injury (TBI). In order to make an instrument for measuring mindfulness within the German speaking clinical community available, a short, easily usable scale and a cross-cultural adaptation is needed. To validate the Langer Mindfulness Scale (LMS) with German-speaking patients with severe TBI and their relatives (healthy controls). In a prospective cohort study of patients with severe TBI, test-re-test interviews were carried out at 6-month intervals. A total of 225 participants responded to the first survey and 230 completed the second survey. LMS, self-report questions on personality, openness and attention, as well as health and clinical evaluations (including cognitive and behavioural assessments). On the basis of factor analysis, principal component analysis and item response analysis, the initial 21-items were reduced to six items. The resulting unidimensional scale showed high internal consistency (α = 0.82) and good test-re-test reliability (intra-class correlation for total score = 0.46). External validity was confirmed for the entire sample. It was concluded that the German short form of the original LMS (MCS) is a valid and reliable measure of mindful creativity.

  10. Full-Scaled Advanced Systems Testbed: Ensuring Success of Adaptive Control Research Through Project Lifecycle Risk Mitigation

    Science.gov (United States)

    Pavlock, Kate M.

    2011-01-01

    The National Aeronautics and Space Administration's Dryden Flight Research Center completed flight testing of adaptive controls research on the Full-Scale Advance Systems Testbed (FAST) in January of 2011. The research addressed technical challenges involved with reducing risk in an increasingly complex and dynamic national airspace. Specific challenges lie with the development of validated, multidisciplinary, integrated aircraft control design tools and techniques to enable safe flight in the presence of adverse conditions such as structural damage, control surface failures, or aerodynamic upsets. The testbed is an F-18 aircraft serving as a full-scale vehicle to test and validate adaptive flight control research and lends a significant confidence to the development, maturation, and acceptance process of incorporating adaptive control laws into follow-on research and the operational environment. The experimental systems integrated into FAST were designed to allow for flexible yet safe flight test evaluation and validation of modern adaptive control technologies and revolve around two major hardware upgrades: the modification of Production Support Flight Control Computers (PSFCC) and integration of two, fourth-generation Airborne Research Test Systems (ARTS). Post-hardware integration verification and validation provided the foundation for safe flight test of Nonlinear Dynamic Inversion and Model Reference Aircraft Control adaptive control law experiments. To ensure success of flight in terms of cost, schedule, and test results, emphasis on risk management was incorporated into early stages of design and flight test planning and continued through the execution of each flight test mission. Specific consideration was made to incorporate safety features within the hardware and software to alleviate user demands as well as into test processes and training to reduce human factor impacts to safe and successful flight test. This paper describes the research configuration

  11. Operator-Adjustable Frame Rate, Resolution, and Gray Scale Tradeoff in Fixed-Bandwidth Remote Manipulator Control.

    Science.gov (United States)

    1980-09-01

    easier. During the Campeche blowout, both a manned and an unmanned submersible were sent for. The remotely controlled TREAC submersible was loaded...hose into a socket would be easiest with high resolution and * relatively low gray scale and frame rate, while selecting the blue valve from a bank of

  12. First-In-Flight Full-Scale Application of Active Flow Control: The XV-15 Tiltrotor Download Reduction

    National Research Council Canada - National Science Library

    Nagib, Hassan M; Kiedaisch, John W; Wygnanski, Israel J; Stalker, Aaron D; Wood, Tom; McVeigh, Michael A

    2004-01-01

    ... Helicopter and Boeing under the sponsorship of the Micro-Adaptive Flow control (MAFC) program of DARPA. The over six hours of flight tests successfully achieved the two goals and documented reduction in the download forces by 9 to 14%, thereby demonstrating for the first time the aerodynamic principals of AFC extend to full-scale flight.

  13. Validation of the MASK-rhinitis visual analogue scale on smartphone screens to assess allergic rhinitis control

    NARCIS (Netherlands)

    Caimmi, D.; Baiz, N.; Tanno, L. K.; Demoly, P.; Arnavielhe, S.; Murray, R.; Bedbrook, A.; Bergmann, K. C.; de Vries, G.; Fokkens, W. J.; Fonseca, J.; Haahtela, T.; Keil, T.; Kuna, P.; Mullol, J.; Papadopoulos, N.; Passalacqua, G.; Samolinski, B.; Tomazic, P. V.; Valiulis, A.; van Eerd, M.; Wickman, M.; Annesi-Maesano, I.; Bousquet, J.; Agache, I.; Angles, R.; Anto, J. M.; Asayag, E.; Bacci, E.; Bachert, C.; Baroni, I.; Barreto, B. A.; Bedolla-Barajas, M.; Bertorello, L.; Bewick, M.; Bieber, T.; Birov, S.; Bindslev-Jensen, C.; Blua, A.; Bochenska Marciniak, M.; Bogus-Buczynska, I.; Bosnic-Ancevich, S.; Bosse, I.; Bourret, R.; Bucca, C.; Buonaiuto, R.; Caiazza, D.; Caillot, D.; Caimmi, D. P.; Camargos, P.; Canfora, G.; Cardona, V.; Carriazo, A. M.; Cartier, C.; Castellano, G.; Chavannes, N. H.; Ciaravolo, M. M.; Cingi, C.; Ciceran, A.; Colas, L.; Colgan, E.; Coll, J.; Conforti, D.; Correira de Sousa, J.; Cortés-Grimaldo, R. M.; Corti, F.; Costa, E.; Courbis, A. L.; Cruz, A.; Custovic, A.; Dario, C.; da Silva, M.; Dauvilliers, Y.; de Blay, F.; Dedeu, T.; de Feo, G.; de Martino, B.; Di Capua, S.; Di Carluccio, N.; Dray, G.; Dubakiene, R.; Eller, E.; Emuzyte, R.; Espinoza-Contreras, J. M.; Estrada-Cardona, A.; Farrell, J.; Ferrero, J.; Fontaine, J. F.; Forti, S.; Gálvez-Romero, J. L.; Garcia Cruz, M. H.; García-Cobas, C. I.; Gemicioğlu, B.; Gerth van Wijck, R.; Guidacci, M.; Gómez-Vera, J.; Guldemond, N. A.; Gutter, Z.; Hajjam, J.; Hellings, P.; Hernández-Velázquez, L.; Illario, M.; Ivancevich, J. C.; Jares, E.; Joos, G.; Just, J.; Kalayci, O.; Kalyoncu, A. F.; Karjalainen, J.; Khaltaev, N.; Klimek, L.; Kull, I.; Kuna, T. P.; Kvedariene, V.; Kolek, V.; Krzych-Fałta, E.; Kupczyk, M.; Lacwik, P.; Larenas-Linnemann, D.; Laune, D.; Lauri, D.; Lavrut, J.; Lessa, M.; Levato, G.; Lewis, L.; Lieten, I.; Lipiec, A.; Louis, R.; Luna-Pech, J. A.; Magnan, A.; Malva, J.; Maspero, J. F.; Mayora, O.; Medina-Ávalos, M. A.; Melen, E.; Menditto, E.; Millot-Keurinck, J.; Moda, G.; Morais-Almeida, M.; Mösges, R.; Mota-Pinto, A.; Muraro, A.; Noguès, M.; Nalin, M.; Napoli, L.; Neffen, H.; O'Hehir, R.; Olivé Elias, M.; Onorato, G.; Palkonen, S.; Pépin, J. L.; Pereira, A. M.; Persico, M.; Pfaar, O.; Pozzi, A. C.; Prokopakis, E. P.; Raciborski, F.; Rizzo, J. A.; Robalo-Cordeiro, C.; Rodríguez-González, M.; Rolla, G.; Roller-Wirnsberger, R. E.; Romano, A.; Romano, M.; Salimäki, J.; Serpa, F. S.; Shamai, S.; Sierra, M.; Sova, M.; Sorlini, M.; Stellato, C.; Stelmach, R.; Strandberg, T.; Stroetman, V.; Stukas, R.; Szylling, A.; Tibaldi, V.; Todo-Bom, A.; Toppila-Salmi, S.; Tomazic, P.; Trama, U.; Triggiani, M.; Valero, A.; Valovirta, E.; Vasankari, T.; Vatrella, A.; Ventura, M. T.; Verissimo, M. T.; Viart, F.; Williams, S.; Wagenmann, M.; Wanscher, C.; Westman, M.; Young, I.; Yorgancioglu, A.; Zernotti, E.; Zurbierber, T.; Zurkuhlen, A.; de Oliviera, B.; Senn, A.

    2017-01-01

    Background: Visual Analogue Scale (VAS) is a validated tool to assess control in allergic rhinitis patients. Objective: The aim of this study was to validate the use of VAS in the MASK-rhinitis (MACVIA-ARIA Sentinel NetworK for allergic rhinitis) app (Allergy Diary) on smartphones screens to

  14. Topographic, meteorologic, and canopy controls on the scaling characteristics of the spatial distribution of snow depth fields

    Science.gov (United States)

    Ernesto Trujillo; Jorge A. Ramirez; Kelly J. Elder

    2007-01-01

    In this study, LIDAR snow depths, bare ground elevations (topography), and elevations filtered to the top of vegetation (topography + vegetation) in five 1-km2 areas are used to determine whether the spatial distribution of snow depth exhibits scale invariance, and the control that vegetation, topography, and winds exert on such behavior. The one-dimensional and mean...

  15. Implementing Mother Tongue Instruction in the Real World: Results from a Medium-Scale Randomized Controlled Trial in Kenya

    Science.gov (United States)

    Piper, Benjamin; Zuilkowski, Stephanie S.; Ong'ele, Salome

    2016-01-01

    Research in sub-Saharan Africa investigating the effect of mother tongue (MT) literacy instruction at medium scale is limited. A randomized controlled trial of MT literacy instruction was implemented in 2013 and 2014 as part of the Primary Math and Reading (PRIMR) Initiative in Kenya. We compare the effect of two treatment groups--the base PRIMR…

  16. Factors Controlling Soil Microbial Biomass and Bacterial Diversity and Community Composition in a Cold Desert Ecosystem: Role of Geographic Scale.

    Directory of Open Access Journals (Sweden)

    David J Van Horn

    Full Text Available Understanding controls over the distribution of soil bacteria is a fundamental step toward describing soil ecosystems, understanding their functional capabilities, and predicting their responses to environmental change. This study investigated the controls on the biomass, species richness, and community structure and composition of soil bacterial communities in the McMurdo Dry Valleys, Antarctica, at local and regional scales. The goals of the study were to describe the relationships between abiotic characteristics and soil bacteria in this unique, microbially dominated environment, and to test the scale dependence of these relationships in a low complexity ecosystem. Samples were collected from dry mineral soils associated with snow patches, which are a significant source of water in this desert environment, at six sites located in the major basins of the Taylor and Wright Valleys. Samples were analyzed for a suite of characteristics including soil moisture, pH, electrical conductivity, soil organic matter, major nutrients and ions, microbial biomass, 16 S rRNA gene richness, and bacterial community structure and composition. Snow patches created local biogeochemical gradients while inter-basin comparisons encompassed landscape scale gradients enabling comparisons of microbial controls at two distinct spatial scales. At the organic carbon rich, mesic, low elevation sites Acidobacteria and Actinobacteria were prevalent, while Firmicutes and Proteobacteria were dominant at the high elevation, low moisture and biomass sites. Microbial parameters were significantly related with soil water content and edaphic characteristics including soil pH, organic matter, and sulfate. However, the magnitude and even the direction of these relationships varied across basins and the application of mixed effects models revealed evidence of significant contextual effects at local and regional scales. The results highlight the importance of the geographic scale of

  17. Scale-dependent controls on the area burned in the boreal forest of Canada, 1980-2005.

    Science.gov (United States)

    Parisien, Marc-André; Parks, Sean A; Krawchuk, Meg A; Flannigan, Mike D; Bowman, Lynn M; Moritz, Max A

    2011-04-01

    In the boreal forest of North America, as in any fire-prone biome, three environmental factors must coincide for a wildfire to occur: an ignition source, flammable vegetation, and weather that is conducive to fire. Despite recent advances, the relative importance of these factors remains the subject of some debate. The aim of this study was to develop models that identify the environmental controls on spatial patterns in area burned for the period 1980-2005 at several spatial scales in the Canadian boreal forest. Boosted regression tree models were built to relate high-resolution data for area burned to an array of explanatory variables describing ignitions, vegetation, and long-term patterns in fire-conducive weather (i.e., fire climate) at four spatial scales (10(2) km2, 10(3) km2, 10(4) km2, and 10(5) km2). We evaluated the relative contributions of these controls on area burned, as well as their functional relationships, across spatial scales. We also assessed geographic patterns of the influence of wildfire controls. The results indicated that extreme temperature during the fire season was a top control at all spatial scales, followed closely by a wind-driven index of ease of fire spread. However, the contributions of some variables differed substantially among the spatial scales, as did their relationship to area burned. In fact, for some key variables the polarity of relationships was inverted from the finest to the broadest spatial scale. It was difficult to unequivocally attribute values of relative importance to the variables chosen to represent ignitions, vegetation, and climate, as the interdependence of these factors precluded clear partitioning. Furthermore, the influence of a variable on patterns of area burned often changed enormously across the biome, which supports the idea that fire-environment relationships in the boreal forest are complex and nonstationary.

  18. Scaling relationships for soil formation and edaphic controls on vegetation growth

    Science.gov (United States)

    Hunt, A. G.; Ghanbarian, B.

    2015-12-01

    Critical path analysis (CPA) is suited to calculating the hydraulic conductivity, K, of heterogeneous porous media by quantifying of paths of least resistance. Whenever CPA could be used to calculate K, advective transport scaling relationships from percolation theory should describe solute transport. Two solute transport relationships are applied to predict soil development and edaphic constraints on natural vegetation growth. These results use known exponents from percolation theory and known subsurface flow velocities. The typical flow velocity itself constrains optimal growth rates of cultivars. The percolation scaling relationship constraining vegetation growth is shown to be in accord with data over time scales from hours to 100,000 years, including over a dozen studies (and two models) of tree growth. The scaling function for soil development explains time scales for formation of soils from years to hundreds of millions of years. Data on soil development comes from 23 different studies. The key unification is the common origin of the time and space coordinates for all three relationships in the time of transport through a single pore of roughly micron size at a typical subsurface pore-scale flow velocity. The distinction in evolving time scales is primarily a result of the hierarchical nature of vascular plant root systems, which speed up nutrient access relative to physical transport rates in the soil. The results help explain reduction in forest productivity with age, diminishing soil production with time, and the temporal distinction between the relevance of chemical and biological processes in soils to the global carbon cycle.

  19. Yolo County's Accelerated Anaerobic and Aerobic Composting (Full-Scale Controlled Landfill Bioreactor) Project

    Science.gov (United States)

    Yazdani, R.; Kieffer, J.; Akau, H.; Augenstein, D.

    2002-12-01

    Sanitary landfilling is the dominant method of solid waste disposal in the United States, accounting for about 217 million tons of waste annually (U.S. EPA, 1997) and has more than doubled since 1960. In spite of increasing rates of reuse and recycling, population and economic growth will continue to render landfilling as an important and necessary component of solid waste management. Yolo County Department of Planning and Public Works, Division of Integrated Waste Management is demonstrating a new landfill technology called Bioreactor Landfill to better manage solid waste. In a Bioreactor Landfill, controlled quantities of liquid (leachate, groundwater, gray-water, etc.) are added and recirculated to increase the moisture content of the waste and improve waste decomposition. As demonstrated in a small-scale demonstration project at the Yolo County Central Landfill in 1995, this process significantly increases the biodegradation rate of waste and thus decreases the waste stabilization and composting time (5 to 10 years) relative to what would occur within a conventional landfill (30 to 50 years or more). When waste decomposes anaerobically (in absence of oxygen), it produces landfill gas (biogas). Biogas is primarily a mixture of methane, a potent greenhouse gas, carbon dioxide, and small amounts of Volatile Organic Compounds (VOC's) which can be recovered for electricity or other uses. Other benefits of a bioreactor landfill composting operation include increased landfill waste settlement which increases in landfill capacity and life, improved leachate chemistry, possible reduction of landfill post-closure management time, opportunity to explore decomposed waste for landfill mining, and abatement of greenhouse gases through highly efficient methane capture over a much shorter period of time than is typical of waste management through conventional landfilling. This project also investigates the aerobic decomposition of waste of 13,000 tons of waste (2.5 acre) for

  20. Online Supplementary ADP Learning Controller Design and Application to Power System Frequency Control With Large-Scale Wind Energy Integration.

    Science.gov (United States)

    Guo, Wentao; Liu, Feng; Si, Jennie; He, Dawei; Harley, Ronald; Mei, Shengwei

    2016-08-01

    The emergence of smart grids has posed great challenges to traditional power system control given the multitude of new risk factors. This paper proposes an online supplementary learning controller (OSLC) design method to compensate the traditional power system controllers for coping with the dynamic power grid. The proposed OSLC is a supplementary controller based on approximate dynamic programming, which works alongside an existing power system controller. By introducing an action-dependent cost function as the optimization objective, the proposed OSLC is a nonidentifier-based method to provide an online optimal control adaptively as measurement data become available. The online learning of the OSLC enjoys the policy-search efficiency during policy iteration and the data efficiency of the least squares method. For the proposed OSLC, the stability of the controlled system during learning, the monotonic nature of the performance measure of the iterative supplementary controller, and the convergence of the iterative supplementary controller are proved. Furthermore, the efficacy of the proposed OSLC is demonstrated in a challenging power system frequency control problem in the presence of high penetration of wind generation.

  1. Regional-scale controls on the spatial activity of rockfalls (Turtmann Valley, Swiss Alps) - A multivariate modeling approach

    Science.gov (United States)

    Messenzehl, Karoline; Meyer, Hanna; Otto, Jan-Christoph; Hoffmann, Thomas; Dikau, Richard

    2017-06-01

    In mountain geosystems, rockfalls are among the most effective sediment transfer processes, reflected in the regional-scale distribution of talus slopes. However, the understanding of the key controlling factors seems to decrease with increasing spatial scale, due to emergent and complex system behavior and not least to recent methodological shortcomings in rockfall modeling research. In this study, we aim (i) to develop a new approach to identify major regional-scale rockfall controls and (ii) to quantify the relative importance of these controls. Using a talus slope inventory in the Turtmann Valley (Swiss Alps), we applied for the first time the decision-tree based random forest algorithm (RF) in combination with a principal component logistic regression (PCLR) to evaluate the spatial distribution of rockfall activity. This study presents new insights into the discussion on whether periglacial rockfall events are controlled more by topo-climatic, cryospheric, paraglacial or/and rock mechanical properties. Both models explain the spatial rockfall pattern very well, given the high areas under the Receiver Operating Characteristic (ROC) curves of > 0.83. Highest accuracy was obtained by the RF, correctly predicting 88% of the rockfall source areas. The RF appears to have a great potential in geomorphic research involving multicollinear data. The regional permafrost distribution, coupled to the bedrock curvature and valley topography, was detected to be the primary rockfall control. Rockfall source areas cluster within a low-radiation elevation belt (2900-3300 m a.s.l,) consistent with a permafrost probability of > 90%. The second most important factor is the time since deglaciation, reflected by the high abundance of rockfalls along recently deglaciated (control on the paraglacial rockfall activity, declining either exponentially or linearly since deglaciation. The study demonstrates the benefit of combined statistical approaches for predicting rockfall activity in

  2. Spatial scale and movement behaviour traits control the impacts of habitat fragmentation on individual fitness.

    Science.gov (United States)

    Cattarino, Lorenzo; McAlpine, Clive A; Rhodes, Jonathan R

    2016-01-01

    Habitat fragmentation, that is the breaking apart of habitat, can occur at multiple spatial scales at the same time, as a result of different land uses. Individuals of most species spend different amounts of times moving in different modes, during which they cover different distances and experience different fitness impacts. The scale at which fragmentation occurs interacts with the distance that individuals move in a particular mode to affect an individual's ability to find habitat. However, there is little knowledge of the fitness consequences of different scales of fragmentation for individuals with different traits of movement behaviour. This is critical to understand the mechanisms of persistence of different species in fragmented landscapes. The aim of this study was to quantify the impacts of habitat fragmentation at different scales on the fitness components (reproduction and survival) of individuals with different traits of movement behaviour. We developed a demographic model of individuals that adopt short and tortuous movements within foraging areas (foraging mode) and long and straight movements between foraging areas (searching mode). We considered individuals that adopt different movement modes with varying frequencies, inherently move different searching distances and experience different risks of mortality during searching. We then applied the model within a spatially explicit simulation framework where we varied simultaneously the degree of fragmentation within (fine scale) and between foraging areas (coarse scale). Fine-scale fragmentation had a greater impact on reproduction and survival than coarse-scale fragmentation, for those individuals with a low searching propensity. The impact of fine-scale fragmentation on reproduction and survival interacted with the impact of coarse-scale fragmentation on reproduction and survival, to affect the fitness of individuals with a high searching propensity, large inherent searching distances and high

  3. Fluid-Mediated Stochastic Self-Assembly at Centimetric and Sub-Millimetric Scales: Design, Modeling, and Control

    Directory of Open Access Journals (Sweden)

    Bahar Haghighat

    2016-08-01

    Full Text Available Stochastic self-assembly provides promising means for building micro-/nano-structures with a variety of properties and functionalities. Numerous studies have been conducted on the control and modeling of the process in engineered self-assembling systems constituted of modules with varied capabilities ranging from completely reactive nano-/micro-particles to intelligent miniaturized robots. Depending on the capabilities of the constituting modules, different approaches have been utilized for controlling and modeling these systems. In the quest of a unifying control and modeling framework and within the broader perspective of investigating how stochastic control strategies can be adapted from the centimeter-scale down to the (sub-millimeter-scale, as well as from mechatronic to MEMS-based technology, this work presents the outcomes of our research on self-assembly during the past few years. As the first step, we leverage an experimental platform to study self-assembly of water-floating passive modules at the centimeter scale. A dedicated computational framework is developed for real-time tracking, modeling and control of the formation of specific structures. Using a similar approach, we then demonstrate controlled self-assembly of microparticles into clusters of a preset dimension in a microfluidic chamber, where the control loop is closed again through real-time tracking customized for a much faster system dynamics. Finally, with the aim of distributing the intelligence and realizing programmable self-assembly, we present a novel experimental system for fluid-mediated programmable stochastic self-assembly of active modules at the centimeter scale. The system is built around the water-floating 3-cm-sized Lily robots specifically designed to be operative in large swarms and allows for exploring the whole range of fully-centralized to fully-distributed control strategies. The outcomes of our research efforts extend the state-of-the-art methodologies

  4. Hardware Development of a Laboratory-Scale Microgrid Phase 2: Operation and Control of a Two-Inverter Microgrid

    Energy Technology Data Exchange (ETDEWEB)

    Illindala, M. S.; Piagi, P.; Zhang, H.; Venkataramanan, G.; Lasseter, R. H.

    2004-03-01

    This report summarizes the activities of the second year of a three-year project to develop control software for microsource distributed generation systems. In this phase, a laboratory-scale microgrid was expanded to include: (1) Two emulated distributed resources; (2) Static switchgear to allow rapid disconnection and reconnection; (3) Electronic synchronizing circuitry to enable transient-free grid interconnection; (4) Control software for dynamically varying the frequency and voltage controller structures; and (5) Power measurement instrumentation for capturing transient waveforms at the interconnect during switching events.

  5. Controlled mixed fermentation at winery scale using Zygotorulaspora florentina and Saccharomyces cerevisiae.

    Science.gov (United States)

    Lencioni, Livio; Romani, Cristina; Gobbi, Mirko; Comitini, Francesca; Ciani, Maurizio; Domizio, Paola

    2016-10-03

    Over the last few years the use of multi-starter inocula has become an attractive biotechnological practice in the search for wine with high flavour complexity or distinctive characters. This has been possible through exploiting the particular oenological features of some non-Saccharomyces yeast strains, and the effects that derive from their specific interactions with Saccharomyces. In the present study, we evaluated the selected strain Zygotorulaspora florentina (formerly Zygosaccharomyces florentinus) in mixed culture fermentations with Saccharomyces cerevisiae, from the laboratory scale to the winery scale. The scale-up fermentation and substrate composition (i.e., white or red musts) influenced the analytical composition of the mixed fermentation. At the laboratory scale, mixed fermentation with Z. florentina exhibited an enhancement of polysaccharides and 2-phenylethanol content and a reduction of volatile acidity. At the winery scale, different fermentation characteristics of Z. florentina were observed. Using Sangiovese red grape juice, sequential fermentation trials showed a significantly higher concentration of glycerol and esters while the sensorial analysis of the resulting wines showed higher floral notes and lower perception of astringency. To our knowledge, this is the first time that this yeasts association has been evaluated at the winery scale indicating the potential use of this mixed culture in red grape varieties. Copyright © 2016. Published by Elsevier B.V.

  6. Controlling the near-wake of a circular cylinder with a single, large-scale tripwire

    Science.gov (United States)

    Aydin, Tayfun Besim

    Control of the flow past a circular cylinder using a single tripwire on its surface has been studied experimentally as a function of the wire angular location for different wire-to-cylinder diameter ratios (0.029 ≤ d/D ≤ 0.059) and Reynolds numbers (5,000 ≤ Re D ≤ 30,000). The use of an endplate with a sharp leading edge on each end of the cylinder yields adequate level of quasi two-dimensionality in the near wake. For each Reynolds number and wire size considered, two types of critical angular locations for the implementation of the large-scale wire on the cylinder surface were shown to exist based on the changes in the flow features in accord with the existing literature. At the first critical wire angle, the vortex shedding ceases for the majority of the time during which the vortex formation length extends, and there exists short time intervals where regular shedding resumes similar to the smooth cylinder. The second critical wire angle is found to encompass a range of angles (50° to 70°) where significant increase in spectral amplitude of Karman frequency is observed together with contraction of the near-wake. The angular location of the first critical wire angle decreases with the wire size, and increases with Reynolds number up to ReD = 15,000, after which it remains unaffected by the Reynolds number. Furthermore, the variations of the Strouhal number and the coherency of Karman vortex shedding are found to be, roughly, inversely related with each other. This investigation explains the relationship between different sets of critical wire angles previously defined by other researchers. Finally, a model is established for the estimation of the Strouhal number as a function of the wire angle. This model requires only the wire size (d), cylinder diameter (D), and Reynolds number (Re D) as inputs, and, therefore, is applicable without any prior knowledge on the flow structures. It yields a low average error (<6.2%) when compared with the experimental

  7. Pilot-scale application of an online VFA sensor for monitoring and control of a manure digester.

    Science.gov (United States)

    Boe, K; Angelidaki, I

    2012-01-01

    A volatile fatty acids (VFA) sensor based on headspace chromatography was tested for online monitoring and control of a pilot-scale manure digester. The sensor showed satisfying results in terms of sensitivity and reliability for monitoring of the digester. The online VFA and biogas production data were used for automatic control of the digester based on feed flow manipulation. The control approach was based on optimization of biogas production while using VFA concentration as the alarm threshold. A rule-based supervisory system with a cascade controller was used to optimize the biogas production from the digester. The alarm state was set at 40 mM total VFA and 10 mM propionate concentration. The control algorithms could successfully maximize the biogas production without overloading the process. However, as the algorithm was based on a fixed biogas yield parameter and only used the biogas parameter for optimization, it could not distinguish between the decreases of biogas production from inhibition and from lower organic content in the substrate, which resulted in undesired decreasing of the control gas setpoint when the substrate was diluted. It was necessary to adjust the yield parameter in order to get this control approach to function properly, which is not suitable for the full-scale biogas plant where the organic content of waste streams can vary. An alternative approach could be a modified rule-based algorithm that includes VFA parameters to help distinguish between different process scenarios.

  8. Challenge of Primary Voltage Control in Large Scale Wind Integrated Power System: A Danish Power System Case Study

    DEFF Research Database (Denmark)

    Rather, Zakir Hussain; Chen, Zhe; Thøgersen, Paul

    2013-01-01

    Grid integration of Renewable Energy (RE) at large scale poses vast majority of challenges to secure and stable operation of Power System. This paper presents the challenge of short circuit power and primary voltage control of wind integrated power system where majority of conventional generators...... of operational and future model of western Danish power system has been presented to support the effectiveness of demonstrated alternatives....... are replaced by wind generators. The impact of large scale wind integration on fast reactive power support is studied in this paper. Considering both technical and economic aspects, alternatives to address the challenge of dynamic voltage support have also been demonstrated in this paper. A case study...

  9. Low velocity tracking control-based ADRC for large-scale telescope system

    Science.gov (United States)

    Cai, Huaxiang; Huang, Yongmei; Du, Junfeng; Tang, Tao; Zuo, Dan

    2015-10-01

    In this paper, an improved Active Disturbance Rejection control (ADRC) method is proposed to enhance the tracking precision of telescope if the telescope runs in a low velocity. Low velocity telescope system usually suffers some obvious nonlinear disturbances, such as nonlinear friction and unknown external disturbance. Thereby, to ensure the tracking precision, multiple loops control structure is a common control method in telescope system, which includes current loop, velocity loop and position loop. The proposed control method is used in the velocity loop which consists of a PD controller and an Extend State Observer (ESO). The ESO is designed to estimate the disturbance involved in the telescope system. Besides, the PD controller is designed to stabilize the closed-loop system. Furthermore, this control method theoretically guarantees a prescribed tracking performance and final tracking accuracy. Finally, the experiment results show that the proposed control method has excellent performance for reducing the tracking error of low velocity.

  10. Robust Decentralized Adaptive Neural Control for a Class of Nonaffine Nonlinear Large-Scale Systems with Unknown Dead Zones

    Directory of Open Access Journals (Sweden)

    Huanqing Wang

    2014-01-01

    Full Text Available The problem of robust decentralized adaptive neural stabilization control is investigated for a class of nonaffine nonlinear interconnected large-scale systems with unknown dead zones. In the controller design procedure, radical basis function (RBF neural networks are applied to approximate packaged unknown nonlinearities and then an adaptive neural decentralized controller is systematically derived without requiring any information on the boundedness of dead zone parameters (slopes and break points. It is proven that the developed control scheme can ensure that all the signals in the closed-loop system are semiglobally uniformly ultimately bounded in the sense of mean square. Simulation study is provided to further demonstrate the effectiveness of the developed control scheme.

  11. Time-Varying Scheme for Non-Centralized Model Predictive Control of Large-scale Systems

    NARCIS (Netherlands)

    Nunez Vicencio, A.A.; Ocampo-Martinez, C.; Maestre, J.M.; De Schutter, B.H.K.

    2015-01-01

    The Non-Centralized Model Predictive Control (NC-MPC) framework refers in this paper to any distributed, hierarchical, or decentralized model predictive controller (or a combination of them) the structure of which can change over time and the control actions of which are not obtained based on a

  12. Tales of two self-control scales: Relations with Five-Factor and HEXACO traits

    NARCIS (Netherlands)

    de Vries, R.E.; van Gelder, J.L.

    2013-01-01

    This study compared the Five-Factor and HEXACO personality correlates of two common self-control constructs - Tangney self-control and Grasmick self-control - and their relations with delinquency. In both a student and a community sample, conscientiousness (mainly the prudence facet) was the most

  13. FPGA Based Efficient Design of Traffic Light Controller using Frequency Scaling for Family of HSTL

    DEFF Research Database (Denmark)

    Sharma, Shivani; Khan, Sadiq; Das, Bhagwan

    2016-01-01

    Traffic blockage is one of the major issues faced by world today. That can be road traffic or air traffic or even water traffic .Traffic Controllers provide the right direction by providing a rule for any kind of Vehicles. The idea goes around designing traffic light controller system which...... are studied for the purpose of making Light Controller Efficient using VHDL....

  14. A Review of Control Strategy of the Large-scale of Electric Vehicles Charging and Discharging Behavior

    Science.gov (United States)

    Kong, Lingyu; Han, Jiming; Xiong, Wenting; Wang, Hao; Shen, Yaqi; Li, Ying

    2017-05-01

    Large scale access of electric vehicles will bring huge challenges to the safe operation of the power grid, and it’s important to control the charging and discharging of the electric vehicle. First of all, from the electric quality and network loss, this paper points out the influence on the grid caused by electric vehicle charging behaviour. Besides, control strategy of electric vehicle charging and discharging has carried on the induction and the summary from the direct and indirect control. Direct control strategy means control the electric charging behaviour by controlling its electric vehicle charging and discharging power while the indirect control strategy by means of controlling the price of charging and discharging. Finally, for the convenience of the reader, this paper also proposed a complete idea of the research methods about how to study the control strategy, taking the adaptability and possibility of failure of electric vehicle control strategy into consideration. Finally, suggestions on the key areas for future research are put up.

  15. Flap/Lag Stall Flutter Control of Large-Scale Wind Turbine Blade Based on Robust H2 Controller

    Directory of Open Access Journals (Sweden)

    Tingrui Liu

    2016-01-01

    Full Text Available Flap/lag stall nonlinear flutter and active control of anisotropic composite wind turbine blade modeled as antisymmetric beam analysis have been investigated based on robust H2 controller. The blade is modeled as single-cell thin-walled beam structure, exhibiting flap bending moment-lag transverse shear deformation, and lag bending moment-flap transverse shear deformation, with constant pitch angle set. The stall flutter control of dynamic response characteristics of composite blade incorporating nonlinear aerodynamic model is investigated based on some structural and dynamic parameters. The aeroelastic partial differential equations are reduced by Galerkin method, with the aerodynamic forces decomposed by strip theory. Robust H2 optimal controller is developed to enhance the vibrational behavior and dynamic response to aerodynamic excitation under extreme wind conditions and stabilize structures that might be damaged in the absence of control. The effectiveness of the control algorithm is demonstrated in both amplitudes and frequencies by description of time responses, extended phase planes, and frequency spectrum analysis, respectively.

  16. The role of storm scale, position and movement in controlling urban flood response

    Science.gov (United States)

    ten Veldhuis, Marie-claire; Zhou, Zhengzheng; Yang, Long; Liu, Shuguang; Smith, James

    2018-01-01

    The impact of spatial and temporal variability of rainfall on hydrological response remains poorly understood, in particular in urban catchments due to their strong variability in land use, a high degree of imperviousness and the presence of stormwater infrastructure. In this study, we analyze the effect of storm scale, position and movement in relation to basin scale and flow-path network structure on urban hydrological response. A catalog of 279 peak events was extracted from a high-quality observational dataset covering 15 years of flow observations and radar rainfall data for five (semi)urbanized basins ranging from 7.0 to 111.1 km2 in size. Results showed that the largest peak flows in the event catalog were associated with storm core scales exceeding basin scale, for all except the largest basin. Spatial scale of flood-producing storm events in the smaller basins fell into two groups: storms of large spatial scales exceeding basin size or small, concentrated events, with storm core much smaller than basin size. For the majority of events, spatial rainfall variability was strongly smoothed by the flow-path network, increasingly so for larger basin size. Correlation analysis showed that position of the storm in relation to the flow-path network was significantly correlated with peak flow in the smallest and in the two more urbanized basins. Analysis of storm movement relative to the flow-path network showed that direction of storm movement, upstream or downstream relative to the flow-path network, had little influence on hydrological response. Slow-moving storms tend to be associated with higher peak flows and longer lag times. Unexpectedly, position of the storm relative to impervious cover within the basins had little effect on flow peaks. These findings show the importance of observation-based analysis in validating and improving our understanding of interactions between the spatial distribution of rainfall and catchment variability.

  17. Nanometer scale high-aspect-ratio trench etching at controllable angles using ballistic reactive ion etching

    Energy Technology Data Exchange (ETDEWEB)

    Cybart, Shane; Roediger, Peter; Ulin-Avila, Erick; Wu, Stephen; Wong, Travis; Dynes, Robert

    2012-11-30

    We demonstrate a low pressure reactive ion etching process capable of patterning nanometer scale angled sidewalls and three dimensional structures in photoresist. At low pressure the plasma has a large dark space region where the etchant ions have very large highly-directional mean free paths. Mounting the sample entirely within this dark space allows for etching at angles relative to the cathode with minimal undercutting, resulting in high-aspect ratio nanometer scale angled features. By reversing the initial angle and performing a second etch we create three-dimensional mask profiles.

  18. Evidence for a common scale O(0.1) m that controls seabed scattering and reverberation in shallow water.

    Science.gov (United States)

    Holland, Charles W

    2012-10-01

    Analysis of the spectral content of long-range reverberation yields two observations. First, there is a remarkably similar scale, O(0.1) m, between three diverse continental shelf regions. This is surprising given the complexity and diversity of geologic processes. Second, there is strong evidence that the scale is associated with heterogeneities within the sediment. Thus, sediment volume scattering, not interface scattering, controls long-range reverberation from a few hundred hertz to several kilohertz. This is also unexpected given that at long ranges the vertical grazing angles are less than the critical angle, and hence the penetration of the acoustic field into the sub-bottom is expected to be modest. The consistency of the scale, O(0.1) m, suggests an underlying feature or mechanism that is consistent across many ostensibly diverse geological settings. Neither the feature nor mechanism is known at this time.

  19. Scale linkage and contingency effects of field-scale and hillslope-scale controls of long-term soil erosion: Anthropogeomorphic sediment flux in agricultural loess watersheds of Southern Germany

    Science.gov (United States)

    Houben, Peter

    2008-10-01

    . In the study area, system scale linkages are marked by the spatial intersection of a finer-scaled managed field system with a broader hillslope-scale framework of 'natural' erosion controls. In the low-gradient study area, field borders exert control over the spatial reference of soil erosion and sedimentation sites. Over time, this brought about a growing historical and spatial contingency change to the soilscape, because of arbitrary spatial changes of the field system which are inherent in its socio-agricultural maintenance. Thus, the very low-gradient and low-erosivity setting of the study area have singled out the agency of human-induced spatial and connectivity controls and contingency for long-term spatial hillslope sediment flux. Although these findings may be less true for different settings, they allow for deriving a generic conceptual model of the linkages between 'natural' and anthropogenic subsystems to interpret the effects of long-term human-induced sediment flux. Accordingly, the resulting balance between on-hillslope net storage and net delivery to streams is scaling with basic physiographic properties of erosivity and sedimentation as well as the degree of anthropogenic hillslope fragmentation. For loess areas in Europe variable fields are fundamental anthropogeomorphic units that determine appropriate system scaling for historic sediment flux analysis and constrain retrodiction and prediction of changing fluxes at a point and a time at watershed scales. Methodical implications address adequate sampling strategies to record soilscape change, as a result of which a critical review of the applicability of the catena concept to long-cultivated hillslopes in central Europe was included. Finally, the suggested refined generic model of long-term, human-controlled sediment flux involves a number of research opportunities, particularly for linking modeling approaches to long-term field records of cultivation-related change in the soilscape.

  20. Controlling Urban Lighting by Human Motion Patterns results from a full Scale Experiment

    DEFF Research Database (Denmark)

    Poulsen, Esben Skouboe; Andersen, Hans Jørgen; Jensen, Ole B.

    2012-01-01

    This paper presents a full-scale experiment investigating the use of human motion intensities as input for interactive illumination of a town square in the city of Aalborg in Denmark. As illuminators sixteen 3.5 meter high RGB LED lamps were used. The activity on the square was monitored by three...

  1. The Brief Self-Control Scale Predicts Jail Inmates’ Recidivism, Substance Dependence, and Post-Release Adjustment

    Science.gov (United States)

    2015-01-01

    Previous research finds that self-control is positively associated with adaptive and negatively associated with maladaptive behavior. However, most previous studies employ cross-sectional designs, low-risk samples, and limited assessments of self-control. This study of 553 jail inmates examined the relationship of a valid measure of self-control (Brief Self-Control Scale; BSCS) completed upon incarceration with behavior before, during, and one year after incarceration. After controlling for positive impression management (PIM), self-control was negatively related to substance misuse, suicidality, risky sex, and criminal history prior to incarceration and post-release illegal substance misuse, recidivism, and positive adjustment. Lower self-control predicted increases in substance dependence at post-release compared to pre-incarceration. Self-control was not related to misbehavior during incarceration, nor alcohol use or HIV-risk behavior one year post-release. Results were consistent as a function of age, race, and gender. This study supports self-control as an important risk and protective factor in a sample of criminal offenders. PMID:24345712

  2. WaveSAX device: design optimization through scale modelling and a PTO strategical control system

    Science.gov (United States)

    Peviani, Maximo; Danelli, Andrea; Dadone, Gianluca; Dalmasso, Alberto

    2017-04-01

    WaveSAX is an innovative OWC (Oscillating Water Column) device for the generation of electricity from wave power, conceived to be installed in coastal marine structures, such as ports and harbours. The device - especially designed for the typical wave climate of Mediterranean Sea - is characterized by two important aspects: flexibility to fit in different structural configurations and replication in a large number of units. A model of the WaveSAX device on a scale 1:5 has been built and tested in the ocean tank at Ecole Centrale de Nantes (France). The study aimed to analyse the behaviour of the device, including two Wells turbine configurations (with three and four blades), with regular and irregular wave conditions in the ocean wave tank. The model and the wave basin were equipped with a series of sensors which allowed to measure the following parameters during the tests: pressure in different points inside the device, the free water surface displacement inside and outside the device, the rotational velocity and the torque at the top of the axis. The tests had the objective to optimize the device design, especially as far as the characteristics of the rotor of the turbine is concern. Although the performance of the WaveSAX has been satisfactory for regular wave conditions, the behaviour of the Wells turbines for irregular wave climate has shown limitations in terms of maintaining the capacity to transform hydraulics energy into mechanical power. To optimize the efficiency of the turbine, an electronical system has been built on the basis of the ocean tank tests. It allows to continuously monitor and command the rotational speed and the torque of the rotor connected with the turbine, and to control in real time the electrical flow of a motor-generator, either absorbing energy as a generator, or providing power to the turbine working as an engine. Two strategies - based on the velocity and the torque control - have been investigate in the electronic test bench

  3. Understanding the Atomic Scale Mechanisms that Control the Attainment of Ultralow Friction and Wear in Carbon-Based Materials

    Science.gov (United States)

    2016-01-16

    2015. 15. Invited. New Insights into Friction and Wear through In-Situ Nanotribology. Joint Symposium of the Surface Science Society of Japan and...and Carpick, R.W. Influence of Surface Passivation on the Friction and Wear Behavior of Ultrananocrystalline Diamond and Tetrahedral Amorphous Carbon...AFRL-AFOSR-JP-TR-2016-0053 Understanding the Atomic Scale Mechanism that controls the attainment of ultralow friction and wear in carbon based

  4. Oscillation Performance and Wide‐area Coordination Control of Power System with Large‐scale Wind Farms

    DEFF Research Database (Denmark)

    Su, Chi

    power flow (OPF) strategy is introduced, with system oscillation damping considered in the constraints of the optimization process. The method is validated by simulations in two test systems. For the power system control aspect, an optimal PMU placement method is used so as to provide full topological...... in the power system; investigating the possible influence of large‐scale wind power integration on system oscillation performance; developing oscillation mitigation strategies for wind farms; and coordinating various damping controllers in the power system. For the power system operation aspect, an optimal...

  5. A new learning strategy for the two-time-scale neural controller with its application to the tracking control of rigid arms

    Science.gov (United States)

    Cheng, W.; Wen, J. T.

    1992-01-01

    A novel fast learning rule with fast weight identification is proposed for the two-time-scale neural controller, and a two-stage learning strategy is developed for the proposed neural controller. The results of the stability analysis show that both the tracking error and the fast weight error will be uniformly bounded and converge to a bounded region which depends only on the accuracy of the slow learning if the system is sufficiently excited. The efficiency of the two-stage learning is also demonstrated by a simulation of a two-link arm.

  6. Analytical Investigation and Control System Set-up of Medium Scale PV Plants for Power Flow Management

    Directory of Open Access Journals (Sweden)

    Rosario Miceli

    2012-11-01

    Full Text Available In the field of photovoltaic (PV plants and energy conversion from renewable sources, a large part of the technical literature is more devoted to practical aspects (new solar cells, electrically driven PV panels, safety, reduction of parasitic currents, etc. than to theoretical investigations. Despite this tendency, this paper presents a mathematical analysis of a medium scale photovoltaic power generation system connected to the distribution network and of its control system. In such a system, the conversion stage is unique due to the absence of a boost chopper. The conducted analysis leads to the interesting conclusion that the inverter used in the plant presents two degrees of freedom, easy to exploit in a control system in which the inverter simultaneously realizes the interconnection to the grid and the MPPT control. The structure of the control system is then presented, discussed and validated by means of numerical simulations.

  7. Hierarchical, decentralized control system for large-scale smart-structures

    Science.gov (United States)

    Algermissen, Stephan; Fröhlich, Tim; Monner, Hans Peter

    2014-08-01

    Active control of sound and vibration has gained much attention in all kinds of industries in the past decade. Future prospects for maximizing airline passenger comfort are especially promising. The objectives of recent research projects in this area are the reduction of noise transmission through thin walled structures such as fuselages, linings or interior elements. Besides different external noise sources, such as the turbulent boundary layer, rotor or jet noise, the actuator and sensor placement as well as different control concepts are addressed. Mostly, the work is focused on a single panel or section of the fuselage, neglecting the fact that for effective noise reduction the entire fuselage has to be taken into account. Nevertheless, extending the scope of an active system from a single panel to the entire fuselage increases the effort for control hardware dramatically. This paper presents a control concept for large structures using distributed control nodes. Each node has the capability to execute a vibration or noise controller for a specific part or section of the fuselage. For maintenance, controller tuning or performance measurement, all nodes are connected to a host computer via Universal Serial Bus (USB). This topology allows a partitioning and distributing of tasks. The nodes execute the low-level control functions. High-level tasks like maintenance, system identification and control synthesis are operated by the host using streamed data from the nodes. By choosing low-price nodes, a very cost effective way of implementing an active system for large structures is realized. Besides the system identification and controller synthesis on the host computer, a detailed view on the hardware and software concept for the nodes is given. Finally, the results of an experimental test of a system running a robust vibration controller at an active panel demonstrator are shown.

  8. Silica dust control in small-scale building/structure demolition operations using good work practice guidance

    Energy Technology Data Exchange (ETDEWEB)

    Muianga, C V; Rice, C H; Succop, P, E-mail: muiangcv@email.uc.ed [Department of Environmental Health, College of Medicine University of Cincinnati. 3223 Eden Ave., Kettering Laboratory, Cincinnati, OH 45267-0056 (United States)

    2009-02-01

    Work practices can influence exposure, especially in small-scale operations conducted by mobile work crews. This study evaluated the use of information on good work practice in control guidance sheets adapted from UK Silica Essentials guidance sheets by trained workers and supervisors employed in small-scale concrete and masonry demolition operations. A one-page employee silica task-based control guidance sheet for each of four demolition tasks and multiple-page silica control guidance for supervisors were developed. Interactive, hands-on worker training on these task-based good work practice controls was developed. Training was presented to 26 participants from two demolition crews. Feedback on the training and task-based good work practice control guidance sheets was elicited. Observations of work practices were made before and after training. Participants indicated gains in knowledge and checklists were used to document skill attainment. The quality of the training and usefulness of the material/skills was rated high by trainees. Increased use of water to suppress dust and wet cleaning methods on the job were documented following the training. Additional follow-up after training is required to determine long-term impact on sustained changes in work practices, and to evaluate the need for refresher training.

  9. Attentional Control Scale for Children: Factor Structure and Concurrent Validity Among Children and Adolescents Referred for Anxiety Disorders.

    Science.gov (United States)

    Melendez, Raquel; Bechor, Michele; Rey, Yasmin; Pettit, Jeremy W; Silverman, Wendy K

    2017-04-01

    The present study examined the factor structure and concurrent validity of the Attentional Control Scale for Children (ACS-C; Muris, de Jong, & Engelen, 2004), a youth self-rating scale of attentional control. A multisource assessment approach was used with 186 children and adolescents referred to an anxiety disorders specialty clinic. Exploratory factor analysis yielded a 2-factor structure with internally consistent and moderately correlated subscales of Attentional Focusing and Attentional Shifting. Total ACS-C and subscale scores demonstrated significant associations with youth and parent ratings of youth anxiety symptoms, youth self ratings of depressive symptoms, and youth diagnosis of attention deficit-hyperactivity disorder. These findings support use of the ACS-C as a self-rating scale of attentional control among referred youth. Future research is encouraged to examine retest reliability of the ACS-C and to evaluate whether its internal structure could be enhanced by removing or modifying items that performed poorly. © 2016 Wiley Periodicals, Inc.

  10. Multi-Time Scale Coordinated Scheduling Strategy with Distributed Power Flow Controllers for Minimizing Wind Power Spillage

    Directory of Open Access Journals (Sweden)

    Yi Tang

    2017-11-01

    Full Text Available The inherent variability and randomness of large-scale wind power integration have brought great challenges to power flow control and dispatch. The distributed power flow controller (DPFC has the higher flexibility and capacity in power flow control in the system with wind generation. This paper proposes a multi-time scale coordinated scheduling model with DPFC to minimize wind power spillage. Configuration of DPFCs is initially determined by stochastic method. Afterward, two sequential procedures containing day-head and real-time scales are applied for determining maximum schedulable wind sources, optimal outputs of generating units and operation setting of DPFCs. The generating plan is obtained initially in day-ahead scheduling stage and modified in real-time scheduling model, while considering the uncertainty of wind power and fast operation of DPFC. Numerical simulation results in IEEE-RTS79 system illustrate that wind power is maximum scheduled with the optimal deployment and operation of DPFC, which confirms the applicability and effectiveness of the proposed method.

  11. Control Synthesis for the Flow-Based Microfluidic Large-Scale Integration Biochips

    DEFF Research Database (Denmark)

    Minhass, Wajid Hassan; Pop, Paul; Madsen, Jan

    2013-01-01

    , such asmicropumps, mixers, and multiplexers, can be built. In this paper we propose, for the first time to our knowledge, a top-down control synthesis framework for the flow-based biochips. Starting from a given biochemical application and a biochip architecture, we synthesize the control logic that is used...

  12. Proportional and Integral Thermal Control System for Large Scale Heating Tests

    Science.gov (United States)

    Fleischer, Van Tran

    2015-01-01

    The National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California) Flight Loads Laboratory is a unique national laboratory that supports thermal, mechanical, thermal/mechanical, and structural dynamics research and testing. A Proportional Integral thermal control system was designed and implemented to support thermal tests. A thermal control algorithm supporting a quartz lamp heater was developed based on the Proportional Integral control concept and a linearized heating process. The thermal control equations were derived and expressed in terms of power levels, integral gain, proportional gain, and differences between thermal setpoints and skin temperatures. Besides the derived equations, user's predefined thermal test information generated in the form of thermal maps was used to implement the thermal control system capabilities. Graphite heater closed-loop thermal control and graphite heater open-loop power level were added later to fulfill the demand for higher temperature tests. Verification and validation tests were performed to ensure that the thermal control system requirements were achieved. This thermal control system has successfully supported many milestone thermal and thermal/mechanical tests for almost a decade with temperatures ranging from 50 F to 3000 F and temperature rise rates from -10 F/s to 70 F/s for a variety of test articles having unique thermal profiles and test setups.

  13. National malaria vector control policy: an analysis of the decision to scale-up larviciding in Nigeria.

    Science.gov (United States)

    Tesfazghi, Kemi; Hill, Jenny; Jones, Caroline; Ranson, Hilary; Worrall, Eve

    2016-02-01

    New vector control tools are needed to combat insecticide resistance and reduce malaria transmission. The World Health Organization (WHO) endorses larviciding as a supplementary vector control intervention using larvicides recommended by the WHO Pesticides Evaluation Scheme (WHOPES). The decision to scale-up larviciding in Nigeria provided an opportunity to investigate the factors influencing policy adoption and assess the role that actors and evidence play in the policymaking process, in order to draw lessons that help accelerate the uptake of new methods for vector control. A retrospective policy analysis was carried out using in-depth interviews with national level policy stakeholders to establish normative national vector control policy or strategy decision-making processes and compare these with the process that led to the decision to scale-up larviciding. The interviews were transcribed, then coded and analyzed using NVivo10. Data were coded according to pre-defined themes from an analytical policy framework developed a priori. Stakeholders reported that the larviciding decision-making process deviated from the normative vector control decision-making process. National malaria policy is normally strongly influenced by WHO recommendations, but the potential of larviciding to contribute to national economic development objectives through larvicide production in Nigeria was cited as a key factor shaping the decision. The larviciding decision involved a restricted range of policy actors, and notably excluded actors that usually play advisory, consultative and evidence generation roles. Powerful actors limited the access of some actors to the policy processes and content. This may have limited the influence of scientific evidence in this policy decision. This study demonstrates that national vector control policy change can be facilitated by linking malaria control objectives to wider socioeconomic considerations and through engaging powerful policy champions to

  14. Nonlinear Model-Based Predictive Control applied to Large Scale Cryogenic Facilities

    CERN Document Server

    Blanco Vinuela, Enrique; de Prada Moraga, Cesar

    2001-01-01

    The thesis addresses the study, analysis, development, and finally the real implementation of an advanced control system for the 1.8 K Cooling Loop of the LHC (Large Hadron Collider) accelerator. The LHC is the next accelerator being built at CERN (European Center for Nuclear Research), it will use superconducting magnets operating below a temperature of 1.9 K along a circumference of 27 kilometers. The temperature of these magnets is a control parameter with strict operating constraints. The first control implementations applied a procedure that included linear identification, modelling and regulation using a linear predictive controller. It did improve largely the overall performance of the plant with respect to a classical PID regulator, but the nature of the cryogenic processes pointed out the need of a more adequate technique, such as a nonlinear methodology. This thesis is a first step to develop a global regulation strategy for the overall control of the LHC cells when they will operate simultaneously....

  15. Irrelevant water-management scales for flood prevention, water harvesting and eutrophication control.

    Science.gov (United States)

    Andersson, Jafet; Arheimer, Berit

    2017-04-01

    This poster will give three examples of popular water-management methods, which we discovered had very little effect in practice because they were applied on irrelevant scales. They all use small scale solutions to large scale problems, and did not provide expected results due to neglecting the magnitude of components in the large-scale water budget. 1) Flood prevention: ponds are considered to be able to buffer water discharge in catchments and was suggested as a measure to reduce the 20-years return floods in an exposed areas in Sweden. However, when experimenting with several ponds allocation and size in a computational model, we found out that ponds had to cover 5-10% of the catchment to convert the 20-yr flood into an average flood. Most effective was to allocate one single water body at the catchment outlet, but this would correspond to 95 km2 which is by far too big to be called a pond. 2) Water Harvesting: At small-scale it is designed to increase water availability and agricultural productivity in smallholder agriculture. On field scale, we show that water harvesting decreases runoff by 55% on average in 62 investigated field-scale trials of drainage area ≤ 1ha in sub-Saharan Africa (Andersson et al., 2011). When upscaling, to river basin scale in South Africa (8-1.8×106 km2), using a scenario approach and the SWAT hydrological model we found that all smallholder fields would not significantly alter downstream river discharge (Sweden during the years 1996-2006 as a measure to reduce coastal eutrophication. From our detailed calculations, the gross removal was estimated at 140 tonnes Nitrogen per year and 12 tonnes Phosphorus per year in these wetlands. However, this only reduced the load to the sea by 0.2% for nitrogen and 0.5% for phosphorus (Arheimer and Pers, 2016). The wetland area was minor compared to the total area and load (41 km2 vs. 164,000 km2). For the eventual effect in the coast, additional consideration must be taken to the coastal

  16. Comparative Analysis of Decoupling Control Methodologies and H∞ Multivariable Robust Control for Variable-Speed, Variable-Pitch Wind Turbines: Application to a Lab-Scale Wind Turbine

    Directory of Open Access Journals (Sweden)

    Sergio Fragoso

    2017-04-01

    Full Text Available This work is focused on the improvement of variable-speed variable-pitch wind turbine performance by means of its control structure. This kind of systems can be considered as multivariable nonlinear processes subjected to undesired interactions between variables and presenting different dynamics at different operational zones. This interaction level and the dynamics uncertainties complicate the control system design. The aim of this work is developing multivariable controllers that cope with such problems. The study shows the applicability of different decoupling methodologies and provides a comparison with a H∞ controller, which is an appropriate strategy to cope with uncertainties. The methodologies have been tested in simulation and verified experimentally in a lab-scale wind turbine. It is demonstrated that the wind turbine presents more interaction at the transition zone. Then, this operational point is used as the nominal one for the controller designs. At this point, decoupling controllers obtain perfect decoupling while the H∞ control presents important interaction in the generated power loop. On the other hand, they are slightly surpassed by the robust design at other points, where perfect decoupling is not achieved. However, decoupling controllers are easier to design and implement, and specifically dynamic simplified decoupling achieve the best global response. Then, it is concluded that the proposed methodologies can be considered for implantation in industrial wind turbines to improve their performance.

  17. LARGE-SCALE MECURY CONTROL TECHNOLOGY TESTING FOR LIGNITE-FIRED UTILITIES-OXIDATION SYSTEMS FOR WET FGD

    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Holmes; Steven A. Benson; Jeffrey S. Thompson

    2004-03-01

    The Energy & Environmental Research Center (EERC) is conducting a consortium-based effort directed toward resolving the mercury (Hg) control issues facing the lignite industry. Specifically, the EERC team--the EERC, EPRI, URS, ADA-ES, Babcock & Wilcox, the North Dakota Industrial Commission, SaskPower, and the Mercury Task Force, which includes Basin Electric Power Cooperative, Otter Tail Power Company, Great River Energy, Texas Utilities (TXU), Montana-Dakota Utilities Co., Minnkota Power Cooperative, BNI Coal Ltd., Dakota Westmoreland Corporation, and the North American Coal Company--has undertaken a project to significantly and cost-effectively oxidize elemental mercury in lignite combustion gases, followed by capture in a wet scrubber. This approach will be applicable to virtually every lignite utility in the United States and Canada and potentially impact subbituminous utilities. The oxidation process is proven at the pilot-scale and in short-term full-scale tests. Additional optimization is continuing on oxidation technologies, and this project focuses on longer-term full-scale testing. The lignite industry has been proactive in advancing the understanding of and identifying control options for Hg in lignite combustion flue gases. Approximately 1 year ago, the EERC and EPRI began a series of Hg-related discussions with the Mercury Task Force as well as utilities firing Texas and Saskatchewan lignites. This project is one of three being undertaken by the consortium to perform large-scale Hg control technology testing to address the specific needs and challenges to be met in controlling Hg from lignite-fired power plants. This project involves Hg oxidation upstream of a system equipped with an electrostatic precipitator (ESP) followed by wet flue gas desulfurization (FGD). The team involved in conducting the technical aspects of the project includes the EERC, Babcock & Wilcox, URS, and ADA-ES. The host sites include Minnkota Power Cooperative Milton R. Young

  18. Managing for Successful Control of Naturally Occurring Asbestos During Large Scale Grading

    Science.gov (United States)

    Saur, R.; Harnish, D.; Cavanaugh, J.; Kendall, K.; Virdee, A.; Ludlam, D.

    2012-12-01

    Pacific Gas and Electric Company recently completed environmental remediation and civil grading of a 35-acre site in San Francisco Bay Area, and the project became recognized with local agencies as having excellent controls systems for naturally-occurring asbestos (NOA). The project began in 2010 and was completed in 2012, and involved excavating and grading over 100,000 tons of soil containing NOA. The work was subject to requirements by state, local and regional agencies, including an asbestos dust mitigation plan for the Bay Area Air Quality Management District. Effective control of NOA is attributed to management approaches combined with effective monitoring and state-of-the-art controls. Management Planning. The contract for construction specified NOA compliance management and controls, including having a NOA-control "czar" ultimately responsible for effective mitigation. An important element was daily pre-planning for excavation/grading that involved both the NOA mitigation experts and construction staff. Personnel Planning and Training. All construction personnel were trained before work regarding NOA hazards and mitigations. Daily tailboards with all construction personnel included discussions of the NOA controls integral to the daily work. Supervision. A NOA mitigation compliance leader was assigned to each excavation operation, responsible for continuously monitoring wind direction and work to ensure mitigation met requirements, and that disturbed areas were hydrosealed or covered. Adaptive Management - Daily and weekly debriefs occurred with those responsible for NOA controls to evaluate effectiveness, and identify improvements needed. If a monitoring result exceeded the project trigger level, work shut down and a root-cause analysis was performed to determine appropriate corrective actions. Deviations of results from background were researched as to cause, and any adjustments identified. Nearby non-project activities were monitored, as they occasionally

  19. Levenson's IPC (Internal-External Control) Scale: A Comparison of Chinese and American Students

    Science.gov (United States)

    Lao, Rosina C.

    1978-01-01

    The results of this study, taken together and compared with data from previous studies, suggest that the locus of control variable may be tapping some basic psychological dimension common to both Chinese and American cultures. (Author/AM)

  20. Coordinated Pitch & Torque Control of Large-Scale Wind Turbine Based on Pareto Eciency Analysis

    DEFF Research Database (Denmark)

    Lin, Zhongwei; Chen, Zhenyu; Wu, Qiuwei

    2018-01-01

    to optimize the controller coordination based on the Pareto optimization theory. Three solutions are obtained through optimization, which includes the optimal torque solution, optimal power solution, and satisfactory solution. Detailed comparisons evaluate the performance of the three selected solutions...

  1. 3D Vision Based Landing Control of a Small Scale Autonomous Helicopter

    Directory of Open Access Journals (Sweden)

    Zhenyu Yu

    2008-11-01

    Full Text Available Autonomous landing is a challenging but important task for Unmanned Aerial Vehicles (UAV to achieve high level of autonomy. The fundamental requirement for landing is the knowledge of the height above the ground, and a properly designed controller to govern the process. This paper presents our research results in the study of landing an autonomous helicopter. The abovetheground height sensing is based on a 3D vision system. We have designed a simple planefitting method for estimating the height over the ground. The method enables vibration free measurement with the camera rigidly attached on the helicopter without using complicated gimbal or active vision mechanism. The estimated height is used by the landing control loop. Considering the ground effect during landing, we have proposed a twostage landing procedure. Two controllers are designed for the two landing stages respectively. The sensing approach and control strategy has been verified in field flight test and has demonstrated satisfactory performance.

  2. Nonlinear Model-Based Predictive Control applied to Large Scale Cryogenic Facilities

    OpenAIRE

    Blanco Vinuela, Enrique; Casas-Cubillos, Juan; de Prada Moraga, Cesar

    2001-01-01

    The thesis addresses the study, analysis, development, and finally the real implementation of an advanced control system for the 1.8 K Cooling Loop of the LHC (Large Hadron Collider) accelerator. The LHC is the next accelerator being built at CERN (European Center for Nuclear Research), it will use superconducting magnets operating below a temperature of 1.9 K along a circumference of 27 kilometers. The temperature of these magnets is a control parameter with strict operating constraints. The...

  3. Surface topography analysis for dimensional quality control of replication at the micrometre scale

    DEFF Research Database (Denmark)

    Balcon, M.; Marinello, F.; Tosello, Guido

    2011-01-01

    Replication of geometrical features and surfaces are present at different production levels, from realization of moulds to final product. Geometrical features must be reproduced within specification limits, to ensure product functionality . In order to control the replication quality, mould...... and replica surfaces must be quantitatively analysed and compared. In the present work, reference simulated surfaces were considered and studied in order to evaluate the effectiveness and traceability of different analysis tools for replication quality control. Topographies were analysed simulating different...

  4. An empirical evaluation of the translation to Brazilian Portuguese of the Loss of Control over Eating Scale (LOCES

    Directory of Open Access Journals (Sweden)

    Felipe Q. da Luz

    2016-02-01

    Full Text Available Abstract Background Loss of control over eating is a key feature of the most prevalent eating disorders. The Loss of Control over Eating Scale (LOCES enables a thorough assessment of loss of control over eating. Objective This study empirically evaluated the translation of the LOCES from English to Brazilian Portuguese. Methods The scale was translated to Brazilian Portuguese and back translated to English in order to check accuracy of the translation. Two hundred and ninety-three medicine and nursing students, 60 males and 233 females, 18-55 years old, with mean body mass index (BMI 23.2 kg/m2 (SD 4.1, recruited between August and December 2014, answered the Brazilian Portuguese LOCES. An exploratory factor analysis was performed. Results Exploratory factor analysis of the Brazilian Portuguese LOCES showed three distinct factors of the loss of control over eating (disgust/negative sensations, cognitive experiences/dissociation, and “positive” effects as well as moderate consistency with previous reports of exploratory factor analysis of the English version. Discussion This study showed satisfactory translation of the LOCES from English to Brazilian Portuguese, which is now ready for further validation.

  5. Crash response data system for the controlled impact demonstration (CID) of a full scale transport aircraft

    Science.gov (United States)

    Calloway, Raymond S.; Knight, Vernie H., Jr.

    NASA Langley's Crash Response Data System (CRDS) which is designed to acquire aircraft structural and anthropomorphic dummy responses during the full-scale transport CID test is described. Included in the discussion are the system design approach, details on key instrumentation subsystems and operations, overall instrumentation crash performance, and data recovery results. Two autonomous high-environment digital flight instrumentation systems, DAS 1 and DAS 2, were employed to obtain research data from various strain gage, accelerometer, and tensiometric sensors installed in the B-720 test aircraft. The CRDS successfully acquired 343 out of 352 measurements of dynamic crash data.

  6. Controlled Cavitation for Scale-Free Heating, Gum Hydration and Emulsification in Food and Consumer Products

    Science.gov (United States)

    Mancosky, Douglas G.; Milly, Paul

    Cavitation is defined as the sudden formation and collapse of bubbles in liquid by means of a mechanical force. As bubbles rapidly form and collapse, pressurized shock waves, localized heating events and tremendous shearing forces occur. As microscopic cavitation bubbles are produced and collapse, shockwaves are given off into the liquid, which can result in heating and/or mixing, similar to ultrasound. These shockwaves can provide breakthrough benefits for the heating of liquids without scale buildup and/or the mixing of liquids with other liquids, gases or solids at the microscopic level to increase the efficiency of the reaction.

  7. Singular Perturbations and Time Scales in Modeling and Control of Dynamic Systems,

    Science.gov (United States)

    1980-11-01

    In urexapl (1 tissimly*sag a "’ he Slasses of tho original chain. For our ezpls(l) J y ea p e P 4 he probab l y o ean U $ tics , ca c hi s -atr x i~s...Lac usreaid the reader chat we have examined the asympto tic behavior of (18) as g-0 by introducing re-. we see from the first three conditions of... Organizacional .orms for Large Scale Svstems - Vol. 11, Davos, Switzerland, Sept. 30-Oct. 5, 1979, Koktovic, P. V., 1. 9. O’.Slley, Jr., and P. Sainuti

  8. Allometric or lean body mass scaling of propofol pharmacokinetics: towards simplifying parameter sets for target-controlled infusions.

    Science.gov (United States)

    Coetzee, Johan Francois

    2012-03-01

    Uncertainty exists as to the most suitable pharmacokinetic parameter sets for propofol target-controlled infusions (TCI). The pharmacokinetic parameter sets currently employed are clearly not universally applicable, particularly when patient attributes differ from those of the subjects who participated in the original research from which the models were derived. Increasing evidence indicates that the pharmacokinetic parameters of propofol can be scaled allometrically as well as in direct proportion to lean body mass (LBM). Appraisal of hitherto published studies suggests that an allometrically scaled pharmacokinetic parameter set may be applicable to a wide range of patients ranging from children to obese adults. On the other hand, there is evidence that propofol pharmacokinetic parameters, scaled linearly to LBM, provide improved dosing in normal and obese adults. The 'Schnider' pharmacokinetic parameter set that has been programmed into commercially available TCI pumps cannot be employed at present for morbidly obese patients (body mass index >40 kg/m2), because of anomalous behaviour of the equation used to calculate LBM, resulting in administration of excessive amounts of propofol. Simulations of TCI using improved equations to calculate LBM indicate that the Schnider model delivers similar amounts of propofol to morbidly obese patients as do the allometrically scaled pharmacokinetic parameter sets. These hypotheses deserve further investigation. To facilitate further investigation, researchers are encouraged to make their data freely available to the WorldSIVA Open TCI Initiative (http://opentci.org).

  9. The Landscape Evolution Observatory: A large-scale controllable infrastructure to study coupled Earth-surface processes

    Science.gov (United States)

    Pangle, Luke A.; DeLong, Stephen B.; Abramson, Nate; Adams, John; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Dietrich, William E.; Dontsova, Katerina; Durcik, Matej; Espeleta, Javier; Ferre, T. P. A.; Ferriere, Regis; Henderson, Whitney; Hunt, Edward A.; Huxman, Travis E.; Millar, David; Murphy, Brendan; Niu, Guo-Yue; Pavao-Zuckerman, Mitch; Pelletier, Jon D.; Rasmussen, Craig; Ruiz, Joaquin; Saleska, Scott; Schaap, Marcel; Sibayan, Michael; Troch, Peter A.; Tuller, Markus; van Haren, Joost; Zeng, Xubin

    2015-09-01

    Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significant ecosystem services, refining our understanding of how these functions are affected by landscape evolution, weather variability, and long-term climate change is imperative. In this paper we introduce the Landscape Evolution Observatory (LEO): a large-scale controllable infrastructure consisting of three replicated artificial landscapes (each 330 m2 surface area) within the climate-controlled Biosphere 2 facility in Arizona, USA. At LEO, experimental manipulation of rainfall, air temperature, relative humidity, and wind speed are possible at unprecedented scale. The Landscape Evolution Observatory was designed as a community resource to advance understanding of how topography, physical and chemical properties of soil, and biological communities coevolve, and how this coevolution affects water, carbon, and energy cycles at multiple spatial scales. With well-defined boundary conditions and an extensive network of sensors and samplers, LEO enables an iterative scientific approach that includes numerical model development and virtual experimentation, physical experimentation, data analysis, and model refinement. We plan to engage the broader scientific community through public dissemination of data from LEO, collaborative experimental design, and community-based model development.

  10. The Landscape Evolution Observatory: a large-scale controllable infrastructure to study coupled Earth-surface processes

    Science.gov (United States)

    Pangle, Luke A.; DeLong, Stephen B.; Abramson, Nate; Adams, John; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Dietrich, William E.; Dontsova, Katerina; Durcik, Matej; Espeleta, Javier; Ferre, T. P. A.; Ferriere, Regis; Henderson, Whitney; Hunt, Edward A.; Huxman, Travis E.; Millar, David; Murphy, Brendan; Niu, Guo-Yue; Pavao-Zuckerman, Mitch; Pelletier, Jon D.; Rasmussen, Craig; Ruiz, Joaquin; Saleska, Scott; Schaap, Marcel; Sibayan, Michael; Troch, Peter A.; Tuller, Markus; van Haren, Joost; Zeng, Xubin

    2015-01-01

    Zero-order drainage basins, and their constituent hillslopes, are the fundamental geomorphic unit comprising much of Earth's uplands. The convergent topography of these landscapes generates spatially variable substrate and moisture content, facilitating biological diversity and influencing how the landscape filters precipitation and sequesters atmospheric carbon dioxide. In light of these significant ecosystem services, refining our understanding of how these functions are affected by landscape evolution, weather variability, and long-term climate change is imperative. In this paper we introduce the Landscape Evolution Observatory (LEO): a large-scale controllable infrastructure consisting of three replicated artificial landscapes (each 330 m2 surface area) within the climate-controlled Biosphere 2 facility in Arizona, USA. At LEO, experimental manipulation of rainfall, air temperature, relative humidity, and wind speed are possible at unprecedented scale. The Landscape Evolution Observatory was designed as a community resource to advance understanding of how topography, physical and chemical properties of soil, and biological communities coevolve, and how this coevolution affects water, carbon, and energy cycles at multiple spatial scales. With well-defined boundary conditions and an extensive network of sensors and samplers, LEO enables an iterative scientific approach that includes numerical model development and virtual experimentation, physical experimentation, data analysis, and model refinement. We plan to engage the broader scientific community through public dissemination of data from LEO, collaborative experimental design, and community-based model development.

  11. Adaptive Fuzzy Output-Constrained Fault-Tolerant Control of Nonlinear Stochastic Large-Scale Systems With Actuator Faults.

    Science.gov (United States)

    Li, Yongming; Ma, Zhiyao; Tong, Shaocheng

    2017-09-01

    The problem of adaptive fuzzy output-constrained tracking fault-tolerant control (FTC) is investigated for the large-scale stochastic nonlinear systems of pure-feedback form. The nonlinear systems considered in this paper possess the unstructured uncertainties, unknown interconnected terms and unknown nonaffine nonlinear faults. The fuzzy logic systems are employed to identify the unknown lumped nonlinear functions so that the problems of structured uncertainties can be solved. An adaptive fuzzy state observer is designed to solve the nonmeasurable state problem. By combining the barrier Lyapunov function theory, adaptive decentralized and stochastic control principles, a novel fuzzy adaptive output-constrained FTC approach is constructed. All the signals in the closed-loop system are proved to be bounded in probability and the system outputs are constrained in a given compact set. Finally, the applicability of the proposed controller is well carried out by a simulation example.

  12. Cryogenic hydrogen fuel for controlled inertial confinement fusion (formation of reactor-scale cryogenic targets)

    Energy Technology Data Exchange (ETDEWEB)

    Aleksandrova, I. V.; Koresheva, E. R., E-mail: elena.koresheva@gmail.com; Krokhin, O. N. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Osipov, I. E. [Power Efficiency Centre, Inter RAO UES (Russian Federation)

    2016-12-15

    In inertial fusion energy research, considerable attention has recently been focused on low-cost fabrication of a large number of targets by developing a specialized layering module of repeatable operation. The targets must be free-standing, or unmounted. Therefore, the development of a target factory for inertial confinement fusion (ICF) is based on methods that can ensure a cost-effective target production with high repeatability. Minimization of the amount of tritium (i.e., minimization of time and space at all production stages) is a necessary condition as well. Additionally, the cryogenic hydrogen fuel inside the targets must have a structure (ultrafine layers—the grain size should be scaled back to the nanometer range) that supports the fuel layer survivability under target injection and transport through the reactor chamber. To meet the above requirements, significant progress has been made at the Lebedev Physical Institute (LPI) in the technology developed on the basis of rapid fuel layering inside moving free-standing targets (FST), also referred to as the FST layering method. Owing to the research carried out at LPI, unique experience has been gained in the development of the FST-layering module for target fabrication with an ultrafine fuel layer, including a reactor- scale target design. This experience can be used for the development of the next-generation FST-layering module for construction of a prototype of a target factory for power laser facilities and inertial fusion power plants.

  13. Variation in reach-scale bankfull discharge of the Jingjiang Reach undergoing upstream and downstream boundary controls

    Science.gov (United States)

    Xia, Junqiang; Zhou, Meirong; Lin, Fenfen; Deng, Shanshan; Lu, Jinyou

    2017-04-01

    Remarkable channel degradation has occurred in the Jingjiang Reach of the Middle Yangtze River, since the operation of the Three Gorges Project, which has caused significant geomorphic adjustments, including the variation in bankfull discharge. Bankfull discharge is a key indicator of flood-discharge capacity in the Jingjiang Reach, which can adjust in response to the altered water and sediment conditions and local base-level changes. Therefore, it is important to investigate the variation in reach-scale bankfull discharge, because of longitudinal variability in channel geometry and bankfull discharge in the study reach. In this study, a general method to calculate the section-scale bankfull discharge using the simulated stage-discharge relation is outlined briefly, and an integrated method is then presented for estimating the reach-scale bankfull discharge. The post-flood reach-scale bankfull discharges in the study reach from 2002 to 2015 were calculated, using the proposed method, based on surveyed post-flood profiles at 171 sections and measured hydrological data at three hydrometric sections and eight water gauge sections. The calculated results indicate that: (i) the reach-scale bankfull discharge in the Jingjiang Reach ranged between 32,731 and 38,949 m3/s over this period, with the average bankfull discharge in the Upper Jingjiang Reach being generally greater than the value in the Lower Jingjiang Reach; (ii) the magnitude of the reach-scale bankfull discharge responded well to the cumulative effect of incoming flow and sediment conditions at the inlet boundary, as well as the change of local base level at the outlet boundary; and (iii) the flood-discharge capacity of the reach was controlled by both the upstream and downstream boundary conditions, and the reach-scale bankfull discharge was expressed by an empirical function of the previous five-year average fluvial erosion intensity during flood seasons at Zhicheng, and the difference between the flood

  14. FPGA Based Efficient Design of Traffic Light Controller using Frequency Scaling for Family of HSTL

    DEFF Research Database (Denmark)

    Sharma, Shivani; Khan, Sadiq; Das, Bhagwan

    2016-01-01

    Traffic blockage is one of the major issues faced by world today. That can be road traffic or air traffic or even water traffic .Traffic Controllers provide the right direction by providing a rule for any kind of Vehicles. The idea goes around designing traffic light controller system which...... utilizes least amount of power and is well tested in hardware using Xilinx Virtex6 Field Programmable gate array. FPGA designs are not only cheaper than ASIC designs but have many positive features like speed and performance. So the factors that contribute to power consumption for family of HSTL...

  15. Controlling mechanical properties of bio-inspired hydrogels by modulating nano-scale, inter-polymeric junctions

    Directory of Open Access Journals (Sweden)

    Seonki Hong

    2014-06-01

    Full Text Available Quinone tanning is a well-characterized biochemical process found in invertebrates, which produce diverse materials from extremely hard tissues to soft water-resistant adhesives. Herein, we report new types of catecholamine PEG derivatives, PEG-NH-catechols that can utilize an expanded spectrum of catecholamine chemistry. The PEGs enable simultaneous participation of amine and catechol in quinone tanning crosslinking. The intermolecular reaction between PEG-NH-catechols forms a dramatic nano-scale junction resulting in enhancement of gelation kinetics and mechanical properties of PEG hydrogels compared to results obtained by using PEGs in the absence of amine groups. Therefore, the study provides new insight into designing new crosslinking chemistry for controlling nano-scale chemical reactions that can broaden unique properties of bulk hydrogels.

  16. Improving Wind Farm Dispatchability Using Model Predictive Control for Optimal Operation of Grid-Scale Energy Storage

    Directory of Open Access Journals (Sweden)

    Douglas Halamay

    2014-09-01

    Full Text Available This paper demonstrates the use of model-based predictive control for energy storage systems to improve the dispatchability of wind power plants. Large-scale wind penetration increases the variability of power flow on the grid, thus increasing reserve requirements. Large energy storage systems collocated with wind farms can improve dispatchability of the wind plant by storing energy during generation over-the-schedule and sourcing energy during generation under-the-schedule, essentially providing on-site reserves. Model predictive control (MPC provides a natural framework for this application. By utilizing an accurate energy storage system model, control actions can be planned in the context of system power and state-of-charge limitations. MPC also enables the inclusion of predicted wind farm performance over a near-term horizon that allows control actions to be planned in anticipation of fast changes, such as wind ramps. This paper demonstrates that model-based predictive control can improve system performance compared with a standard non-predictive, non-model-based control approach. It is also demonstrated that secondary objectives, such as reducing the rate of change of the wind plant output (i.e., ramps, can be considered and successfully implemented within the MPC framework. Specifically, it is shown that scheduling error can be reduced by 81%, reserve requirements can be improved by up to 37%, and the number of ramp events can be reduced by 74%.

  17. On Event-Triggered Adaptive Architectures for Decentralized and Distributed Control of Large-Scale Modular Systems

    Directory of Open Access Journals (Sweden)

    Ali Albattat

    2016-08-01

    Full Text Available The last decade has witnessed an increased interest in physical systems controlled over wireless networks (networked control systems. These systems allow the computation of control signals via processors that are not attached to the physical systems, and the feedback loops are closed over wireless networks. The contribution of this paper is to design and analyze event-triggered decentralized and distributed adaptive control architectures for uncertain networked large-scale modular systems; that is, systems consist of physically-interconnected modules controlled over wireless networks. Specifically, the proposed adaptive architectures guarantee overall system stability while reducing wireless network utilization and achieving a given system performance in the presence of system uncertainties that can result from modeling and degraded modes of operation of the modules and their interconnections between each other. In addition to the theoretical findings including rigorous system stability and the boundedness analysis of the closed-loop dynamical system, as well as the characterization of the effect of user-defined event-triggering thresholds and the design parameters of the proposed adaptive architectures on the overall system performance, an illustrative numerical example is further provided to demonstrate the efficacy of the proposed decentralized and distributed control approaches.

  18. An Algebraic Approach to Analysis and Control of Time-Scales.

    Science.gov (United States)

    1983-10-01

    prevented. CAD A#~ 43 EIINO O 5I IIOUNCLASSIFIED SR C AFOSR-TR. 3-- 0954 October, 1983 LIDS-P- 1235 An Algebraic Aproach to Analysis and Control of Tine...E) is non- singular in the neighborhood of 0 in writing (3.2); in the more general case, some of the diagonal terms would be 0). Actual computation

  19. 3D Vision Based Landing Control of a Small Scale Autonomous Helicopter

    Directory of Open Access Journals (Sweden)

    Zhenyu Yu

    2007-03-01

    Full Text Available Autonomous landing is a challenging but important task for Unmanned Aerial Vehicles (UAV to achieve high level of autonomy. The fundamental requirement for landing is the knowledge of the height above the ground, and a properly designed controller to govern the process. This paper presents our research results in the study of landing an autonomous helicopter. The above-the-ground height sensing is based on a 3D vision system. We have designed a simple plane-fitting method for estimating the height over the ground. The method enables vibration free measurement with the camera rigidly attached on the helicopter without using complicated gimbal or active vision mechanism. The estimated height is used by the landing control loop. Considering the ground effect during landing, we have proposed a two-stage landing procedure. Two controllers are designed for the two landing stages respectively. The sensing approach and control strategy has been verified in field flight test and has demonstrated satisfactory performance.

  20. Replication molds having nanometer-scale shape control fabricated by means of oxidation and etching

    NARCIS (Netherlands)

    Kim, G.M.; Kovalgin, Alexeij Y.; Holleman, J.; Brugger, J.P.

    2002-01-01

    A means of accurate control of the curvature radius of molds that are used in nanostructure replication techniques is presented. The local non-uniform growth of SiO2 at regions with high curvature is used to fabricate molds with a curvature radius ranging anywhere between 10 and 250 nm. The mold

  1. COSIGN – developing an optical software controlled data plane for future large-scale datacenter networks

    DEFF Research Database (Denmark)

    Galili, Michael; Kamchevska, Valerija; Fagertun, Anna Manolova

    2015-01-01

    This talk will present the work of the EU project COSIGN targeting the development of optical data plane solutions for future high-capacity datacenter networks (DCNs). Optical data planes with high capacity and high flexibility through software control are developed in order to enable a coherent...

  2. Full-Scale Transport Controlled Impact Demonstration Program Photographic/Video Coverage.

    Science.gov (United States)

    1986-04-01

    distance from camera to subject, atmospheric effects (heat, mirage, aerial refractions, etc.), must be considered. e. Radio communcations between the...rewind slide use of the Nikon Speedlight SB-5 at shooting rates uc to 38 frames per second: remote operation via the Modulite Unit (ML-1. Wireless Control

  3. Effective landscape scale management of Cirsium arvense (Canada thistle) utilizing biological control

    Science.gov (United States)

    G. P. Markin; D. Larson

    2013-01-01

    The stem mining weevil, Ceutorhynchus litura Fabricius, the gall forming fly, Urophora cardui L., and the seedhead weevil, Larinus planus Fabricius, were established as biological control agents on an 1800 hectare multiple-habitat wildlife refuge in northwestern Oregon in the mid-1990s. At the time, Canada thistle was the most wide spread, aggressive, and difficult...

  4. Large-Scale CORBA-Distributed Software Framework for NIF Controls

    Energy Technology Data Exchange (ETDEWEB)

    Carey, R W; Fong, K W; Sanchez, R J; Tappero, J D; Woodruff, J P

    2001-10-16

    The Integrated Computer Control System (ICCS) is based on a scalable software framework that is distributed over some 325 computers throughout the NIF facility. The framework provides templates and services at multiple levels of abstraction for the construction of software applications that communicate via CORBA (Common Object Request Broker Architecture). Various forms of object-oriented software design patterns are implemented as templates to be extended by application software. Developers extend the framework base classes to model the numerous physical control points, thereby sharing the functionality defined by the base classes. About 56,000 software objects each individually addressed through CORBA are to be created in the complete ICCS. Most objects have a persistent state that is initialized at system start-up and stored in a database. Additional framework services are provided by centralized server programs that implement events, alerts, reservations, message logging, database/file persistence, name services, and process management. The ICCS software framework approach allows for efficient construction of a software system that supports a large number of distributed control points representing a complex control application.

  5. Scaled Bilateral Teleoperation Using Discrete-Time Sliding-Mode Controller

    NARCIS (Netherlands)

    Khan, S.; Sabanovic, A.; Nergiz, A.O.

    2009-01-01

    In this paper, the design of a discrete-time sliding-mode controller based on Lyapunov theory is presented along with a robust disturbance observer and is applied to a piezostage for high-precision motion. A linear model of a piezostage was used with nominal parameters to compensate the disturbance

  6. Global stabilisation of large-scale hydraulic networks with quantised and positive proportional controls

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard; Wisniewski, Rafal

    2013-01-01

    is extended by showing that an attractor set with a global basin of attraction exists for arbitrary values of positive control gains, given that the upper level of the quantiser is properly designed. Furthermore, the proof is given for general monotone quantisation maps. Since the basin of attraction...

  7. Global asymptotic stabilization of large-scale hydraulic networks using positive proportional controls

    DEFF Research Database (Denmark)

    Jensen, Tom Nørgaard; Wisniewski, Rafal

    2014-01-01

    directional actuator constraints is addressed. The proposed solution consists of a set of decentralized positively constrained proportional control actions. The results show that the closed-loop system always has a globally asymptotically stable equilibrium point independently on the number of end...

  8. An Autonomous Autopilot Control System Design for Small-Scale UAVs

    Science.gov (United States)

    Ippolito, Corey; Pai, Ganeshmadhav J.; Denney, Ewen W.

    2012-01-01

    This paper describes the design and implementation of a fully autonomous and programmable autopilot system for small scale autonomous unmanned aerial vehicle (UAV) aircraft. This system was implemented in Reflection and has flown on the Exploration Aerial Vehicle (EAV) platform at NASA Ames Research Center, currently only as a safety backup for an experimental autopilot. The EAV and ground station are built on a component-based architecture called the Reflection Architecture. The Reflection Architecture is a prototype for a real-time embedded plug-and-play avionics system architecture which provides a transport layer for real-time communications between hardware and software components, allowing each component to focus solely on its implementation. The autopilot module described here, although developed in Reflection, contains no design elements dependent on this architecture.

  9. A Congestion Control Strategy for Power Scale-Free Communication Network

    Directory of Open Access Journals (Sweden)

    Min Xiang

    2017-10-01

    Full Text Available The scale-free topology of power communication network leads to more data flow in less hub nodes, which can cause local congestion. Considering the differences of the nodes’ delivery capacity and cache capacity, an integrated routing based on the communication service classification is proposed to reduce network congestion. In the power communication network, packets can be classified as key operational services (I-level and affairs management services (II-level. The shortest routing, which selects the path of the least hops, is adopted to transmit I-level packets. The load-balanced global dynamic routing, which uses the node’s queue length and delivery capacity to establish the cost function and chooses the path with minimal cost, is adopted to transmit II-level packets. The simulation results show that the integrated routing has a larger critical packet generation rate and can effectively reduce congestion.

  10. Understanding regional and local scale hydraulic processes controlling recharge through drift

    Science.gov (United States)

    Cuthbert, M. O.; Mackay, R.; Lawrence, A. R.; Peach, D.

    2003-04-01

    The estimation of groundwater recharge is a fundamental component of any water resources appraisal or aquifer vulnerability study. Although methods for evaluating the distribution of potential recharge leaving the soil zone are relatively well developed, the recharge signal to the underlying aquifer can be significantly modified in the presence of superficial drift deposits. Current mapping of the drift does not often provide representations of drift distribution and structure suitable for understanding the hydraulics of the subsurface flow system. The current research seeks to develop new understanding of the processes contributing to recharge in heterogeneous drift sequences, their characterisation in models and their parameterisation through field experiments. Surface and downhole geophysical sampling through regional to micro scales will be integrated with textural measurements and hydraulic monitoring to characterise drift deposits in parts of the Tern catchment (Shropshire, UK) and gain insight into the relationship between flow behaviour and geological structure. Fieldwork will then culminate in a series of flow and tracer tests at a well characterised site with continuous monitoring including the use of recently developed 4-D resistivity imaging methods to monitor the movement of natural and applied waters through the drift. Conceptual and numerical models will be used throughout the project to test ideas and drive the experimental designs. The study aims to assess the relative importance of hydraulic processes at a range of scales and, by back analysis, the degree of sophistication required in fieldwork to construct a useful model of flow patterns within the drift. The potential usefulness of various surface and downhole geophysical techniques within drift and unsaturated zone studies will be critically assessed.

  11. PAA-PAMPS copolymers as an efficient tool to control CaCO3 scale formation.

    Science.gov (United States)

    Dietzsch, Michael; Barz, Matthias; Schüler, Timo; Klassen, Stefanie; Schreiber, Martin; Susewind, Moritz; Loges, Niklas; Lang, Michael; Hellmann, Nadja; Fritz, Monika; Fischer, Karl; Theato, Patrick; Kühnle, Angelika; Schmidt, Manfred; Zentel, Rudolf; Tremel, Wolfgang

    2013-03-05

    Scale formation, the deposition of certain minerals such as CaCO3, MgCO3, and CaSO4·2H2O in industrial facilities and household devices, leads to reduced efficiency or severe damage. Therefore, incrustation is a major problem in everyday life. In recent years, double hydrophilic block copolymers (DHBCs) have been the focus of interest in academia with regard to their antiscaling potential. In this work, we synthesized well-defined blocklike PAA-PAMPS copolymers consisting of acrylic acid (AA) and 2-acrylamido-2-methyl-propane sulfonate (AMPS) units in a one-step reaction by RAFT polymerization. The derived copolymers had dispersities of 1.3 and below. The copolymers have then been investigated in detail regarding their impact on the different stages of the crystallization process of CaCO3. Ca(2+) complexation, the first step of a precipitation process, and polyelectrolyte stability in aqueous solution have been investigated by potentiometric measurements, isothermal titration calorimetry (ITC), and dynamic light scattering (DLS). A weak Ca(2+) induced copolymer aggregation without concomitant precipitation was observed. Nucleation, early particle growth, and colloidal stability have been monitored in situ with DLS. The copolymers retard or even completely suppress nucleation, most probably by complexation of solution aggregates. In addition, they stabilize existing CaCO3 particles in the nanometer regime. In situ AFM was used as a tool to verify the coordination of the copolymer to the calcite (104) crystal surface and to estimate its potential as a growth inhibitor in a supersaturated CaCO3 environment. All investigated copolymers instantly stopped further crystal growth. The carboxylate richest copolymer as the most promising antiscaling candidate proved its enormous potential in scale inhibition as well in an industrial-filming test (Fresenius standard method).

  12. Multiple Scales of Control on the Structure and Spatial Distribution of Woody Vegetation in African Savanna Watersheds.

    Directory of Open Access Journals (Sweden)

    Nicholas R Vaughn

    Full Text Available Factors controlling savanna woody vegetation structure vary at multiple spatial and temporal scales, and as a consequence, unraveling their combined effects has proven to be a classic challenge in savanna ecology. We used airborne LiDAR (light detection and ranging to map three-dimensional woody vegetation structure throughout four savanna watersheds, each contrasting in geologic substrate and climate, in Kruger National Park, South Africa. By comparison of the four watersheds, we found that geologic substrate had a stronger effect than climate in determining watershed-scale differences in vegetation structural properties, including cover, height and crown density. Generalized Linear Models were used to assess the spatial distribution of woody vegetation structural properties, including cover, height and crown density, in relation to mapped hydrologic, topographic and fire history traits. For each substrate and climate combination, models incorporating topography, hydrology and fire history explained up to 30% of the remaining variation in woody canopy structure, but inclusion of a spatial autocovariate term further improved model performance. Both crown density and the cover of shorter woody canopies were determined more by unknown factors likely to be changing on smaller spatial scales, such as soil texture, herbivore abundance or fire behavior, than by our mapped regional-scale changes in topography and hydrology. We also detected patterns in spatial covariance at distances up to 50-450 m, depending on watershed and structural metric. Our results suggest that large-scale environmental factors play a smaller role than is often attributed to them in determining woody vegetation structure in southern African savannas. This highlights the need for more spatially-explicit, wide-area analyses using high resolution remote sensing techniques.

  13. Multiple Scales of Control on the Structure and Spatial Distribution of Woody Vegetation in African Savanna Watersheds.

    Science.gov (United States)

    Vaughn, Nicholas R; Asner, Gregory P; Smit, Izak P J; Riddel, Edward S

    2015-01-01

    Factors controlling savanna woody vegetation structure vary at multiple spatial and temporal scales, and as a consequence, unraveling their combined effects has proven to be a classic challenge in savanna ecology. We used airborne LiDAR (light detection and ranging) to map three-dimensional woody vegetation structure throughout four savanna watersheds, each contrasting in geologic substrate and climate, in Kruger National Park, South Africa. By comparison of the four watersheds, we found that geologic substrate had a stronger effect than climate in determining watershed-scale differences in vegetation structural properties, including cover, height and crown density. Generalized Linear Models were used to assess the spatial distribution of woody vegetation structural properties, including cover, height and crown density, in relation to mapped hydrologic, topographic and fire history traits. For each substrate and climate combination, models incorporating topography, hydrology and fire history explained up to 30% of the remaining variation in woody canopy structure, but inclusion of a spatial autocovariate term further improved model performance. Both crown density and the cover of shorter woody canopies were determined more by unknown factors likely to be changing on smaller spatial scales, such as soil texture, herbivore abundance or fire behavior, than by our mapped regional-scale changes in topography and hydrology. We also detected patterns in spatial covariance at distances up to 50-450 m, depending on watershed and structural metric. Our results suggest that large-scale environmental factors play a smaller role than is often attributed to them in determining woody vegetation structure in southern African savannas. This highlights the need for more spatially-explicit, wide-area analyses using high resolution remote sensing techniques.

  14. Synthetic-jet-based dynamic stall control on a scaled finite span wind turbine S817 blade

    Science.gov (United States)

    Rice, Thomas; Taylor, Keith; Amitay, Michael

    2016-11-01

    As wind turbines increase in size, so do many of the adverse effects associated with unsteady flow fields. Yawed flow, unsteady gusts, atmospheric boundary layers, and even free stream turbulence can cause unsteady loading, which are detrimental to the blades' structure. In order to decrease unsteady loading, synthetic jet actuators were installed on a scaled finite span cantilevered wind turbine blade having an S817 airfoil shape. The S817 airfoil shape is of the blade tips on the NREL CART3, which will be used next year on full scale field testing of active flow control. The model has been tested in the wind tunnel with and without active flow control, using load, surface pressure, and PIV measurements to characterize the airfoil's stall behavior during static and dynamic conditions, and the effect of flow control on its aerodynamic performance. Surface-mounted microphones were also used to detect dominant frequencies in the flow field. Dynamic stall was also simulated by pitching the airfoil through stall in a sinusoidal pitching motion. Synthetic jets, placed near the leading edge, were shown to increase lift both in the static and dynamic cases, in addition to attaching the flow and reducing hysteresis during dynamic pitching, showing a decrease in structural loading.

  15. Research and realization of ten-print data quality control techniques for imperial scale automated fingerprint identification system

    Directory of Open Access Journals (Sweden)

    Qian Wang

    2017-01-01

    Full Text Available As the first individualization-information processing equipment put into practical service worldwide, Automated Fingerprint Identification System (AFIS has always been regarded as the first choice in individualization of criminal suspects or those who died in mass disasters. By integrating data within the existing regional large-scale AFIS database, many countries are constructing an ultra large state-of-the-art AFIS (or Imperial Scale AFIS system. Therefore, it is very important to develop a series of ten-print data quality controlling process for this system of this type, which would insure a substantial matching efficiency, as the pouring data come into this imperial scale being. As the image quality of ten-print data is closely relevant to AFIS matching proficiency, a lot of police departments have allocated huge amount of human and financial resources over this issue by carrying out manual verification works for years. Unfortunately, quality control method above is always proved to be inadequate because it is an astronomical task involved, in which it has always been problematic and less affiant for potential errors. Hence, we will implement quality control in the above procedure with supplementary-acquisition effect caused by the delay of feedback instructions sent from the human verification teams. In this article, a series of fingerprint image quality supervising techniques has been put forward, which makes it possible for computer programs to supervise the ten-print image quality in real-time and more accurate manner as substitute for traditional manual verifications. Besides its prominent advantages in the human and financial expenditures, it has also been proved to obviously improve the image quality of the AFIS ten-print database, which leads up to a dramatic improvement in the AFIS-matching accuracy as well.

  16. Cost-effective control of plant disease when epidemiological knowledge is incomplete: modelling Bahia bark scaling of citrus.

    Directory of Open Access Journals (Sweden)

    Nik J Cunniffe

    2014-08-01

    Full Text Available A spatially-explicit, stochastic model is developed for Bahia bark scaling, a threat to citrus production in north-eastern Brazil, and is used to assess epidemiological principles underlying the cost-effectiveness of disease control strategies. The model is fitted via Markov chain Monte Carlo with data augmentation to snapshots of disease spread derived from a previously-reported multi-year experiment. Goodness-of-fit tests strongly supported the fit of the model, even though the detailed etiology of the disease is unknown and was not explicitly included in the model. Key epidemiological parameters including the infection rate, incubation period and scale of dispersal are estimated from the spread data. This allows us to scale-up the experimental results to predict the effect of the level of initial inoculum on disease progression in a typically-sized citrus grove. The efficacies of two cultural control measures are assessed: altering the spacing of host plants, and roguing symptomatic trees. Reducing planting density can slow disease spread significantly if the distance between hosts is sufficiently large. However, low density groves have fewer plants per hectare. The optimum density of productive plants is therefore recovered at an intermediate host spacing. Roguing, even when detection of symptomatic plants is imperfect, can lead to very effective control. However, scouting for disease symptoms incurs a cost. We use the model to balance the cost of scouting against the number of plants lost to disease, and show how to determine a roguing schedule that optimises profit. The trade-offs underlying the two optima we identify-the optimal host spacing and the optimal roguing schedule-are applicable to many pathosystems. Our work demonstrates how a carefully parameterised mathematical model can be used to find these optima. It also illustrates how mathematical models can be used in even this most challenging of situations in which the underlying

  17. A small scale field trial with expanded polystyrene beads for mosquito control in septic tanks.

    Science.gov (United States)

    Chang, M S; Lian, S; Jute, N

    1995-01-01

    A field trial of the use of expanded polystyrene beads (EPSB) to control the breeding of mosquito larvae in household septic tanks was conducted in Sarawak. One week after treatment, the breeding of Culex quinquefasciatus and Aedes albopictus was reduced by 100% and 68.7% respectively. For both species combined, a 57.25% reduction in the adult emergence rate was achieved. No adult was caught in the emergence trap one month after treatment. A reduction in mosquito biting rates was reported by 87.3% of respondents. All households regarded the EPSB treatment as effective. This study has reduced the relatively high infestation rate of A. albopictus in the septic tanks to 16-20%. The EPSB treatment is feasible and practical. Post-treatment assessment using adult emergence traps and the implications for the vector control programme of the local authority are discussed.

  18. A new technique to control floating body effect in nano-scale double-gate MOSFET

    Science.gov (United States)

    Zare, Meisam; Etaati, Gholamreza

    2014-11-01

    This paper proposes a novel structure of Double Gate (DG) MOSFET to control the impacts of floating body effect. Floating body effect increases hole concentration in the channel region due to the impact ionization. In this novel structure which is named as SiGe Region in DG-MOSFET (SR-DG) two spacers are considered in both sides of gate region and a SiGe zone is incorporated in gate-source spacer. The SiGe region with lower band gap than silicon collects the excess hole in the channel. Our simulation with two dimensional ATLAS simulator shows that the proposed SR-DG improves the performance of DG-MOSFET in terms of threshold voltage, breakdown voltage and electric field. Also, the impacts of parasitic bipolar junction transistor (BJT) are controlled significantly.

  19. Note: Design and development of wireless controlled aerosol sampling network for large scale aerosol dispersion experiments

    Science.gov (United States)

    Gopalakrishnan, V.; Subramanian, V.; Baskaran, R.; Venkatraman, B.

    2015-07-01

    Wireless based custom built aerosol sampling network is designed, developed, and implemented for environmental aerosol sampling. These aerosol sampling systems are used in field measurement campaign, in which sodium aerosol dispersion experiments have been conducted as a part of environmental impact studies related to sodium cooled fast reactor. The sampling network contains 40 aerosol sampling units and each contains custom built sampling head and the wireless control networking designed with Programmable System on Chip (PSoC™) and Xbee Pro RF modules. The base station control is designed using graphical programming language LabView. The sampling network is programmed to operate in a preset time and the running status of the samplers in the network is visualized from the base station. The system is developed in such a way that it can be used for any other environment sampling system deployed in wide area and uneven terrain where manual operation is difficult due to the requirement of simultaneous operation and status logging.

  20. Opposing effects of aging on large-scale brain systems for memory encoding and cognitive control.

    Science.gov (United States)

    Salami, Alireza; Eriksson, Johan; Nyberg, Lars

    2012-08-01

    Episodic memory declines with advancing age. Neuroimaging studies have associated such decline to age-related changes in general cognitive-control networks as well as to changes in process-specific encoding or retrieval networks. To assess the specific influence of aging on encoding and retrieval processes and associated brain systems, it is vital to dissociate encoding and retrieval from each other and from shared cognitive-control processes. We used multivariate partial-least-squares to analyze functional magnetic resonance imaging data from a large population-based sample (n = 292, 25-80 years). The participants performed a face-name paired-associates task and an active baseline task. The analysis revealed two significant network patterns. The first reflected a process-general encoding-retrieval network that included frontoparietal cortices and posterior hippocampus. The second pattern dissociated encoding and retrieval networks. The anterior hippocampus was differentially engaged during encoding. Brain scores, representing whole-brain integrated measures of how strongly an individual recruited a brain network, were correlated with cognitive performance and chronological age. The scores from the general cognitive-control network correlated negatively with episodic memory performance and positively with age. The encoding brain scores, which strongly reflected hippocampal functioning, correlated positively with episodic memory performance and negatively with age. Univariate analyses confirmed that bilateral hippocampus showed the most pronounced activity reduction in older age, and brain structure analyses found that the activity reduction partly related to hippocampus atrophy. Collectively, these findings suggest that age-related structural brain changes underlie age-related reductions in the efficient recruitment of a process-specific encoding network, which cascades into upregulated recruitment of a general cognitive-control network.

  1. Tick control by small-scale cattle farmers in the central Eastern Cape Province, South Africa

    OpenAIRE

    P.J. Masika; A. Sonandi; W. Van Averbeke

    1997-01-01

    A survey conducted in 5 magisterial districts involving rapid rural appraisal and a questionnaire showed participation in state-managed and funded dipping programmes by cattle owners in communal areas of the central Eastern Cape to be nearly complete, with 98 % of livestock owners interviewed participating in all dipping events. Disease control was the main reason for participation, but farmers perceive dipping to have a much broader disease-preventing activity than is really the case. Other ...

  2. Lifetime and size of shallow magma bodies controlled by crustal-scale magmatism

    OpenAIRE

    Karakas, Ozge; Degruyter, Wim; Bachmann, Olivier; Dufek, Josef

    2017-01-01

    Magmatic processes on Earth govern the mass, energy and chemical transfer between the mantle, crust and atmosphere. To understand magma storage conditions in the crust that ultimately control volcanic activity and growth of continents, an evaluation of the mass and heat budget of the entire crustal column during magmatic episodes is essential. Here we use a numerical model to constrain the physical conditions under which both lower and upper crustal magma bodies form. We find that over long d...

  3. Tick control by small-scale cattle farmers in the central Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    P.J. Masika

    1997-07-01

    Full Text Available A survey conducted in 5 magisterial districts involving rapid rural appraisal and a questionnaire showed participation in state-managed and funded dipping programmes by cattle owners in communal areas of the central Eastern Cape to be nearly complete, with 98 % of livestock owners interviewed participating in all dipping events. Disease control was the main reason for participation, but farmers perceive dipping to have a much broader disease-preventing activity than is really the case. Other reasons for participation in dipping programmes were to prevent ticks from sucking blood, provide animals with a clean appearance, and prevent damage to teats of cows. Many livestock owners complement dipping with other tick control measures, including old motor oil, household disinfectant, pour-on acaricide and manual removal of ticks. Recently local farming communities were given the responsibility of buying dipping acaricide. This has presented them with the challenge of developing farmer-managed, cost-effective tick control programmes. At present, this process is constrained by lack of information and farmer training.

  4. Scaled experiments using the helium technique to study the vehicular blockage effect on longitudinal ventilation control in tunnels

    DEFF Research Database (Denmark)

    Alva, Wilson Ulises Rojas; Jomaas, Grunde; Dederichs, Anne

    2015-01-01

    A model tunnel (1:30 compared to a standard tunnel section) with a helium-air smoke mixture was used to study the vehicular blockage effect on longitudinal ventilation smoke control. The experimental results showed excellent agreement with full-scale data and confirmed that the critical velocity...... decreases in proportion with the blockage ratio. Nevertheless, it was found that the relative position of the fire source and the relative size of the vehicular blockage can have an opposite effect, as the vehicular blockage influenced the critical and confinement velocity. The method demonstrated...... the ability to provide valuable information on the effect of vehicular blockage on tunnel fire dynamics....

  5. Use of sorbents for air toxics control in a pilot-scale COHPAC baghouse

    Energy Technology Data Exchange (ETDEWEB)

    Butz, J.R.; Chang, R.; Waugh, E.G.; Jensen, B.K.; Lapatnick, L.N.

    1999-07-01

    With funding from EPRI and Public Service Electric and Gas (PSE and G), ADA Technologies has been operating a COHPAC (COmpact Hybrid PArticulate Collector) pulse-jet pilot plant at PSE and G's Hudson station in Jersey City, NJ to expand the application of COHPAC in anticipation of hazardous air pollutants (HAP) regulations. The pilot extracts a slipstream of flue gas from downstream of Hudson's full-scale ESP (a four-field Research Cottrell unit). A series of tests has been run over the past two and one-half years to evaluate the injection of dry sorbents upstream of the COHPAC pilot for removal of acid gases and mercury from the flue gas slipstream. The COHPAC baghouse subsequently removes the sorbent material from the flue gas. Gas samples were taken upstream of sorbent injection and downstream of the pilot to characterize the ability of the sorbents to remove targeted HAPs. The operation of the pilot was also monitored during testing to characterize the impact of sorbent injection on the performance of the baghouse. Data collected during 1998 are compared to data from 1997, when the pilot was operated at a higher air-to-cloth ratio.

  6. Large-Scale Controls of North American Cold Spells and European Windstorms

    Science.gov (United States)

    Messori, Gabriele; Harnik, Nili; Caballero, Rodrigo; Feldstein, Steven; Gaetani, Marco

    2017-04-01

    During recent winters, both extreme cold events in eastern North America and stormy, rainy weather over western Europe have garnered widespread scientific and media coverage. Their notable co-occurrence raises the question of whether there may be a systematic, physically based link between the two. Here, we explore the statistics and dynamics of these coordinated extremes in reanalysis products. The cold spells are driven by wavenumber 5 wave packets which induce a northerly advection of cold air from the Arctic region into North America. We link these wavepackets to the second Circumglobal Teleconnection Pattern introduced by Branstator and defined as the second EOF of the monthly-mean upper-tropospheric meridional wind. The waves are seen to propagate all the way from Eurasia, across North America and into the Atlantic. Over the North Atlantic, the large-scale circulation associated with the cold spells corresponds to a very zonal and intense jet stream, shifted persistently south of its climatological location. These features of the Atlantic jet are conducive to destructive windstorms and intense precipitation over a large part of southern and continental Europe and the British Isles. We note that the atmospheric patterns we discuss over both North America and the North Atlantic are distinct from well-known modes of climate variability such as the PNA and the NAO.

  7. Controlled oxidation of graphite to graphene oxide with novel oxidants in a bulk scale.

    Science.gov (United States)

    Wojtoniszak, Malgorzata; Mijowska, Ewa

    2012-11-01

    In this study, a novel method of graphite chemical exfoliation to create graphene oxide (GO) is reported. Here, new oxidants were examined: a mixture of perchloric and nitric acids and potassium chromate. Furthermore, an effect of oxidation time, temperature of oxidation, and ultrasonication on graphite exfoliation degree was investigated. The obtained GOs were next reduced with glucose, used as a reducing agent. Detailed analysis of the materials indicated that when graphite was oxidized for 24 h at 50 °C, 5-layered graphene was prepared. An effect of sonication process was also examined, and it was found to enhance the exfoliation to bilayer graphene. Furthermore, when time and temperature were increased to 48 h and 100 °C, respectively, graphite was exfoliated to single-layer graphene. Therefore, it is believed that the proposed route can be applied for the preparation of graphene or few-layered graphene with defined number of layers upon the process parameters optimization and in a bulk scale. The materials were characterized with atomic force microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction.

  8. Primary control of a Mach scale swashplateless rotor using brushless DC motor actuated trailing edge flaps

    Science.gov (United States)

    Saxena, Anand

    The focus of this research was to demonstrate a four blade rotor trim in forward flight using integrated trailing edge flaps instead of using a swashplate controls. A compact brushless DC motor was evaluated as an on-blade actuator, with the possibility of achieving large trailing edge flap amplitudes. A control strategy to actuate the trailing edge flap at desired frequency and amplitude was developed and large trailing edge flap amplitudes from the motor (instead of rotational motion) were obtained. Once the actuator was tested on the bench-top, a lightweight mechanism was designed to incorporate the motor in the blade and actuate the trailing edge flaps. A six feet diameter, four bladed composite rotor with motor-flap system integrated into the NACA 0012 airfoil section was fabricated. Systematic testing was carried out for a range of load conditions, first in the vacuum chamber followed by hover tests. Large trailing edge flap deflections were observed during the hover testing, and a peak to peak trailing edge flap amplitude of 18 degree was achieved at 2000 rotor RPM with hover tip Mach number of 0.628. A closed loop controller was designed to demonstrate trailing edge flap mean position and the peak to peak amplitude control. Further, a soft pitch link was designed and fabricated, to replace the stiff pitch link and thereby reduce the torsional stiffness of the blade to 2/rev. This soft pitch link allowed for blade root pitch motion in response to the trailing edge flap inputs. Blade pitch response due to both steady as well as sinusoidal flap deflections were demonstrated. Finally, tests were performed in Glenn L. Martin wind tunnel using a model rotor rig to assess the performance of motor-flap system in forward flight. A swashplateless trim using brushless DC motor actuated trailing edge flaps was achieved for a rotor operating at 1200 RPM and an advance ratio of 0.28. Also, preliminary exploration was carried out to test the scalability of the motor

  9. Control and Protection in Low Voltage Grid with Large Scale Renewable Electricity Generation

    DEFF Research Database (Denmark)

    Mustafa, Ghullam

    (s). Islanding is a situation where electrical system becomes electrically isolated from the rest of the power network and yet continues to be energized by the DG units connected to it. With the increased penetration of DG units, islanded operation of the distribution network is used to improve the reliability...... or voltage in MG decreases or increases respectively. It requires the significant amount of energy available in the power source with very fast response. A VF control cannot be used for wind and solar power generations because they are unpredictable and depend on the weather conditions (i.e. wind speed...

  10. An automatic device for the quality control of large-scale crystal's production

    CERN Document Server

    Baccaro, S; Castellani, M; Cecilia, A; Dafinei, I; Diemoz, M; Guerra, S; Longo, E; Montecchi, M; Organtini, G; Pellegrini, F

    2001-01-01

    In 1999, the construction of the electromagnetic calorimeter of the Compact Muon Solenoid (CMS) experiment started. Half of the barrel calorimeter made of 61200 lead tungstate (PWO) crystals will be assembled and tested in the Regional Centre of INFN-ENEA in Rome, Italy. Before assembling, all 30600 PWO crystals will be qualified for scintillation and radiation hardness characteristics by a specially built Automatic Crystal Control System. The measuring techniques for crystal qualification and performances of the automatic system will be discussed in this work. (11 refs).

  11. Multi-Time Scale Control of Demand Flexibility in Smart Distribution Networks

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu P.; Myers, Kurt S.; Bak-Jensen, Birgitte

    2017-01-01

    maximization of economic benefits to the participating actors. This is ensured by enabling EV participation in day-ahead, balancing, and regulation markets. For the given network configuration and pricing structure, HCA ensures the EV owners to get paid up to five times the cost they were paying without......This paper presents a multi-timescale control strategy to deploy electric vehicle (EV) demand flexibility for simultaneously providing power balancing, grid congestion management, and economic benefits to participating actors. First, an EV charging problem is investigated from consumer, aggregator...

  12. The Effortful Control Scale for adults: psychometric properties of the Catalan version and its relationship to cognitive emotion regulation

    Directory of Open Access Journals (Sweden)

    Miquel Tortella-Feliu

    2013-10-01

    Full Text Available The goals of this study were (a to examine the psychometric properties of a Catalan version of the Effortful control scale of the Adult Temperament Questionnaire short-form and (b to analyze the relationships among effortful control (EC, negative affectivity (NA, and the use of negative cognitive emotion regulation (ER strategies. In a sample of 353 college students, the instrument presents acceptable internal consistency, temporal stability and convergent validity; however, in general, psychometric properties are poorer than those reported for other versions. Confirmatory factor analysis fit indices revealed an overall poor fit for the three-factor theoretical model. Additionally, it has been found that the proneness to engage in negative cognitive ER strategies was mainly related with exhibiting high NA. Further, although such tendencies were also influenced by EC capabilities, data did not show EC moderating the relationships among NA, anxiety, and the use of negative cognitive ER strategies.

  13. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation: Control modules C4, C6

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This Manual represents Revision 5 of the user documentation for the modular code system referred to as SCALE. The history of the SCALE code system dates back to 1969 when the current Computational Physics and Engineering Division at Oak Ridge National Laboratory (ORNL) began providing the transportation package certification staff at the U. S. Atomic Energy Commission with computational support in the use of the new KENO code for performing criticality safety assessments with the statistical Monte Carlo method. From 1969 to 1976 the certification staff relied on the ORNL staff to assist them in the correct use of codes and data for criticality, shielding, and heat transfer analyses of transportation packages. However, the certification staff learned that, with only occasional use of the codes, it was difficult to become proficient in performing the calculations often needed for an independent safety review. Thus, shortly after the move of the certification staff to the U.S. Nuclear Regulatory Commission (NRC), the NRC staff proposed the development of an easy-to-use analysis system that provided the technical capabilities of the individual modules with which they were familiar. With this proposal, the concept of the Standardized Computer Analyses for Licensing Evaluation (SCALE) code system was born. This volume is part of the manual related to the control modules for the newest updated version of this computational package.

  14. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation. Control modules -- Volume 1, Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    Landers, N.F.; Petrie, L.M.; Knight, J.R. [Oak Ridge National Lab., TN (United States)] [and others

    1995-04-01

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automate the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system has been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.2 of the system. This manual is divided into three volumes: Volume 1--for the control module documentation, Volume 2--for the functional module documentation, and Volume 3 for the documentation of the data libraries and subroutine libraries.

  15. Investigation of the Contamination Control in a Cleaning Room with a Moving AGV by 3D Large-Scale Simulation

    Directory of Open Access Journals (Sweden)

    Qing-He Yao

    2013-01-01

    Full Text Available The motions of the airflow induced by the movement of an automatic guided vehicle (AGV in a cleanroom are numerically studied by large-scale simulation. For this purpose, numerical experiments scheme based on domain decomposition method is designed. Compared with the related past research, the high Reynolds number is treated by large-scale computation in this work. A domain decomposition Lagrange-Galerkin method is employed to approximate the Navier-Stokes equations and the convection diffusion equation; the stiffness matrix is symmetric and an incomplete balancing preconditioned conjugate gradient (PCG method is employed to solve the linear algebra system iteratively. The end wall effects are readily viewed, and the necessity of the extension to 3 dimensions is confirmed. The effect of the high efficiency particular air (HEPA filter on contamination control is studied and the proper setting of the speed of the clean air flow is also investigated. More details of the recirculation zones are revealed by the 3D large-scale simulation.

  16. Taking innovative vector control interventions in urban Latin America to scale: lessons learnt from multi-country implementation research.

    Science.gov (United States)

    Quintero, Juliana; García-Betancourt, Tatiana; Caprara, Andrea; Basso, Cesar; Garcia da Rosa, Elsa; Manrique-Saide, Pablo; Coelho, Giovanini; Sánchez-Tejeda, Gustavo; Dzul-Manzanilla, Felipe; García, Diego Alejandro; Carrasquilla, Gabriel; Alfonso-Sierra, Eduardo; Monteiro Vasconcelos Motta, Cyntia; Sommerfeld, Johannes; Kroeger, Axel

    2017-09-01

    Prior to the current public health emergency following the emergence of chikungunya and Zika Virus Disease in the Americas during 2014 and 2015, multi-country research investigated between 2011 and 2013 the efficacy of novel Aedes aegypti intervention packages through cluster randomised controlled trials in four Latin-American cities: Fortaleza (Brazil); Girardot (Colombia), Acapulco (Mexico) and Salto (Uruguay). Results from the trials led to a scaling up effort of the interventions at city levels. Scaling up refers to deliberate efforts to increase the impact of successfully tested health interventions to benefit more people and foster policy and program development in a sustainable way. The different scenarios represent examples for  a 'vertical approach' and a 'horizontal approach'. This paper presents the analysis of a preliminary process evaluation of the scaling up efforts in the mentioned cites, with a focus on challenges and enabling factors encountered by the research teams, analysing the main social, political, administrative, financial and acceptance factors.

  17. A multi-scale model of hepcidin promoter regulation reveals factors controlling systemic iron homeostasis.

    Directory of Open Access Journals (Sweden)

    Guillem Casanovas

    2014-01-01

    Full Text Available Systemic iron homeostasis involves a negative feedback circuit in which the expression level of the peptide hormone hepcidin depends on and controls the iron blood levels. Hepcidin expression is regulated by the BMP6/SMAD and IL6/STAT signaling cascades. Deregulation of either pathway causes iron-related diseases such as hemochromatosis or anemia of inflammation. We quantitatively analyzed how BMP6 and IL6 control hepcidin expression. Transcription factor (TF phosphorylation and reporter gene expression were measured under co-stimulation conditions, and the promoter was perturbed by mutagenesis. Using mathematical modeling, we systematically analyzed potential mechanisms of cooperative and competitive promoter regulation by the transcription factors, and experimentally validated the model predictions. Our results reveal that hepcidin cross-regulation primarily occurs by combinatorial transcription factor binding to the promoter, whereas signaling crosstalk is insignificant. We find that the presence of two BMP-responsive elements enhances the steepness of the promoter response towards the iron-sensing BMP signaling axis, which promotes iron homeostasis in vivo. IL6 co-stimulation reduces the promoter sensitivity towards the BMP signal, because the SMAD and STAT transcription factors compete for recruiting RNA polymerase to the transcription start site. This may explain why inflammatory signals disturb iron homeostasis in anemia of inflammation. Taken together, our results reveal why the iron homeostasis circuit is sensitive to perturbations implicated in disease.

  18. A randomised controlled trial to explore attitudes to routine scale and polish and compare manual versus ultrasonic scaling in the general dental service in Scotland [ISRCTN99609795

    Science.gov (United States)

    Bonner, Brian C; Young, Linda; Smith, Patricia A; McCombes, Wendy; Clarkson, Jan E

    2005-01-01

    Background To investigate, within general dental practice, patients' and vocational dental practitioners' (VDP) attitudes towards the benefits and costs of a simple scale and polish and to compare the experience of using manual versus ultrasonic instruments to scale teeth. Methods 28 VDPs and 420 patients participated. Patients were randomly allocated to either group. Patients' and VDPs' attitudes towards, and experience of, the scale and polish were elicited by means of self-administered questionnaires. Results The majority of patients (99%) believed a scale and polish was beneficial. VDPs considered ultrasonic treatment to be appropriate on significantly more occasions than they did for manual scale and polish (P < 0.001). Patient discomfort: with ultrasonic scaling 69.2% felt 'a little uncomfortable' or worse compared with 60% of those undergoing manual treatment (P = 0.072). VDPs considered treatment charges were appropriate for 77% of patients. Conclusion Routine scaling and polishing is considered beneficial by both patients and vocational trainees. The majority of patients, regardless of treatment method, experience some degree of discomfort when undergoing a scale and polish. VDPs showed a preference for the ultrasonic treatment method. PMID:15975140

  19. Determining the control circuitry of redox metabolism at the genome-scale.

    Directory of Open Access Journals (Sweden)

    Stephen Federowicz

    2014-04-01

    Full Text Available Determining how facultative anaerobic organisms sense and direct cellular responses to electron acceptor availability has been a subject of intense study. However, even in the model organism Escherichia coli, established mechanisms only explain a small fraction of the hundreds of genes that are regulated during electron acceptor shifts. Here we propose a qualitative model that accounts for the full breadth of regulated genes by detailing how two global transcription factors (TFs, ArcA and Fnr of E. coli, sense key metabolic redox ratios and act on a genome-wide basis to regulate anabolic, catabolic, and energy generation pathways. We first fill gaps in our knowledge of this transcriptional regulatory network by carrying out ChIP-chip and gene expression experiments to identify 463 regulatory events. We then interfaced this reconstructed regulatory network with a highly curated genome-scale metabolic model to show that ArcA and Fnr regulate >80% of total metabolic flux and 96% of differential gene expression across fermentative and nitrate respiratory conditions. Based on the data, we propose a feedforward with feedback trim regulatory scheme, given the extensive repression of catabolic genes by ArcA and extensive activation of chemiosmotic genes by Fnr. We further corroborated this regulatory scheme by showing a 0.71 r(2 (p<1e-6 correlation between changes in metabolic flux and changes in regulatory activity across fermentative and nitrate respiratory conditions. Finally, we are able to relate the proposed model to a wealth of previously generated data by contextualizing the existing transcriptional regulatory network.

  20. Control parameters of the martian dune field positions at planetary scale: tests by the MCD

    Science.gov (United States)

    allemand, pascal

    2016-04-01

    The surface of Mars is occupied by more than 500 dunes fields mainly located inside impact craters of the south hemisphere and near the north polar cap. The questions of the activity of martian dunes and of the localization of the martian dune fields are not completely solved. It has been demonstrated recently by image observation and image correlation that some of these dune fields are clearly active. The sand flux of one of them has been even estimated. But there is no global view of the degree of activity of each the dune fields. (2)The topography of impact craters in which dune fields are localized is an important factor of their position. But there is no consensus of the effect of global atmospheric circulation on dune field localization. These two questions are addressed using the results of Mars Climate Database 5.2 (MCD) (Millour, 2015; Forget et al., 1999). The wind fields of the MCD have been first validated against the observations made on active dune fields. Using a classical transport law, the Drift Potential (DP) and the Relative Drift Potential (RDP) have been computed for each dune fields. A good correlation exists between the position of dune fields and specific values of these two parameters. The activity of each dune field is estimated from these parameters and tested on some examples by image observations. Finally a map of sand flow has been computed at the scale of the planet. This map shows that sand and dust is trapped in specific regions. These regions correspond to the area of dune field concentration.

  1. Preliminary Scaling and controls Analysis of an FHR-HTSE System Idaho National Laboratory Summer 2013 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Bragg-Sitton, Shannon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sabharwall, Piyush [Idaho National Lab. (INL), Idaho Falls, ID (United States); Upadhya, Rohit [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-01-01

    For new nuclear reactor system designs to be approved by regulatory agencies like the Nuclear Regulatory Commission (NRC), the details of system operation must be validated with respect to standards of safety, control, and output. A scaled experiment that replicates certain properties of the system can be used to validate compliance with regulatory standards, while avoiding the prohibitive cost and labor required to develop a fully functional prototype system; therefore, designing such an experiment is of special interest to current efforts to develop hybrid energy systems (HES) that integrate small modular reactors (SMRs), renewable energy systems, and industrial process applications such as hydrogen production and desalination. In addition, a scaled experiment can be an economical method of analyzing the interconnections between HES components and understanding the time constants associated between inter-component energy and information flows. This report discusses the results of a preliminary scaling analysis done for the primary loop of a 300 MWth Fluoride-Salt-Cooled High Temperature Reactor (FHR) that is coupled with a High-Temperature Steam Electrolysis system (HTSE), as well as the basic control logic that governs the primary components and the necessary hardware to achieve optimal functionality. The scaled facility will be a 1 MWth system that uses Dowtherm A as the simulant fluid for Flibe (the coolant of choice for the primary loop of molten salt reactors), and can validate the heat transfer and steady-state operational requirements of the 300 MWth prototype. The scaled facility matches the Prandtl and Reynolds numbers associated with steady-state operation of the FHR-HTSE’s primary loop without having to deal with very high temperatures, flow rates, or power inputs. This will allow the facility to run experiments that analyze various thermophysical and fluid-dynamic properties that characterize reactor operation, such as pressure drops, radial

  2. Preliminary Scaling and controls Analysis of an FHR-HTSE System Idaho National Laboratory Summer 2013 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Upadhya, Rohit [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bragg-Sitton, Shannon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sabharwall, Piyush [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2013-08-01

    For new nuclear reactor system designs to be approved by regulatory agencies like the Nuclear Regulatory Commission (NRC), the details of system operation must be validated with respect to standards of safety, control, and output. A scaled experiment that replicates certain properties of the system can be used to validate compliance with regulatory standards, while avoiding the prohibitive cost and labor required to develop a fully functional prototype system; therefore, designing such an experiment is of special interest to current efforts to develop hybrid energy systems (HES) that integrate small modular reactors (SMRs), renewable energy systems, and industrial process applications such as hydrogen production and desalination. In addition, a scaled experiment can be an economical method of analyzing the interconnections between HES components and understanding the time constants associated between inter-component energy and information flows. This report discusses the results of a preliminary scaling analysis done for the primary loop of a 300 MWth Fluoride-Salt-Cooled High Temperature Reactor (FHR) that is coupled with a High-Temperature Steam Electrolysis system (HTSE), as well as the basic control logic that governs the primary components and the necessary hardware to achieve optimal functionality. The scaled facility will be a 1 MWth system that uses Dowtherm A as the simulant fluid for Flibe (the coolant of choice for the primary loop of molten salt reactors), and can validate the heat transfer and steady-state operational requirements of the 300 MWth prototype. The scaled facility matches the Prandtl and Reynolds numbers associated with steady-state operation of the FHR-HTSE’s primary loop without having to deal with very high temperatures, flow rates, or power inputs. This will allow the facility to run experiments that analyze various thermophysical and fluid-dynamic properties that characterize reactor operation, such as pressure drops, radial

  3. Comparison of alternative versions of the job demand-control scales in 17 European cohort studies: the IPD-Work consortium

    Directory of Open Access Journals (Sweden)

    Fransson Eleonor I

    2012-01-01

    Full Text Available Abstract Background Job strain (i.e., high job demands combined with low job control is a frequently used indicator of harmful work stress, but studies have often used partial versions of the complete multi-item job demands and control scales. Understanding whether the different instruments assess the same underlying concepts has crucial implications for the interpretation of findings across studies, harmonisation of multi-cohort data for pooled analyses, and design of future studies. As part of the 'IPD-Work' (Individual-participant-data meta-analysis in working populations consortium, we compared different versions of the demands and control scales available in 17 European cohort studies. Methods Six of the 17 studies had information on the complete scales and 11 on partial scales. Here, we analyse individual level data from 70 751 participants of the studies which had complete scales (5 demand items, 6 job control items. Results We found high Pearson correlation coefficients between complete scales of job demands and control relative to scales with at least three items (r > 0.90 and for partial scales with two items only (r = 0.76-0.88. In comparison with scores from the complete scales, the agreement between job strain definitions was very good when only one item was missing in either the demands or the control scale (kappa > 0.80; good for job strain assessed with three demand items and all six control items (kappa > 0.68 and moderate to good when items were missing from both scales (kappa = 0.54-0.76. The sensitivity was > 0.80 when only one item was missing from either scale, decreasing when several items were missing in one or both job strain subscales. Conclusions Partial job demand and job control scales with at least half of the items of the complete scales, and job strain indices based on one complete and one partial scale, seemed to assess the same underlying concepts as the complete survey instruments.

  4. Modeling sorbent injection for mercury control in baghouse filters: II--pilot-scale studies and model evaluation.

    Science.gov (United States)

    Flora, Joseph R V; Hargis, Richard A; O'Dowd, William J; Pennline, Henry W; Vidic, Radisav D

    2003-04-01

    Activated carbon injection for Hg control in a 500-lb/hr pilot-scale coal-fired furnace equipped with a fabric filter for particulate control was evaluated at different operating conditions. The pilot-scale tests showed that Hg removal was improved at lower temperatures and higher C/Hg ratios. The two-stage mathematical model developed to describe Hg removal using powdered activated carbon injection upstream of a baghouse filter was used to obtain Langmuir isotherm parameters as a function of temperature by fitting the model to a subset of experimental data. The predictive capability of the model was then tested by comparing model calculations with additional experimental data from this system obtained using different operating temperatures and sorbent to Hg ratios. Model predictions were in good agreement with experimentally measured Hg removal efficiency. Based on the model predictions, Hg removal in the duct appears to be limited and higher C/Hg ratio, lower operating temperature, and longer cleaning cycle of the baghouse filter should be utilized to achieve higher Hg removal in this system.

  5. Modeling sorbent injection for mercury control in baghouse filters: II - pilot-scale studies and model evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Joseph R.V. Flora; Richard A. Hargis; William J. O' Dowd; Henry W. Pennline; Radisav D. Vidic [University of South Carolina, Columbia, SC (United States). Department of Civil and Environmental Engineering

    2003-04-01

    Activated carbon injection for Hg control in a 500-lb/hr pilot-scale coal-fired furnace equipped with a fabric filter for particulate control was evaluated at different operating conditions. The pilot-scale tests showed that Hg removal was improved at lower temperatures and higher C/Hg ratios. The two-stage mathematical model developed to describe Hg removal using powdered activated carbon injection upstream of a baghouse filter was used to obtain Langmuir isotherm parameters as a function of temperature by fitting the model to a subset of experimental data. The predictive capability of the model was then tested by comparing model calculations with additional experimental data from this system obtained using different operating temperatures and sorbent to Hg ratios. Model predictions were in good agreement with experimentally measured Hg removal efficiency. Based on the model predictions, Hg removal in the duct appears to be limited and higher C/Hg ratio, lower operating temperature, and longer cleaning cycle of the baghouse filter should be utilized to achieve higher Hg removal in this system. 27 refs., 8 figs., 3 tabs.

  6. Controlling kilometre-scale interferometric detectors for gravitational wave astronomy: Active phase noise cancellation using EOMs

    Energy Technology Data Exchange (ETDEWEB)

    Arnaud, N.; Balembois, L.; Bizouard, M.A.; Brisson, V. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Casanueva, J., E-mail: casanuev@lal.in2p3.fr [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Cavalier, F.; Davier, M.; Frey, V.; Hello, P.; Huet, D.; Leroy, N. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Loriette, V.; Maksimovic, I. [ESPCI, CNRS, F-75005 Paris (France); Robinet, F. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France)

    2017-02-11

    The second generation of Gravitational waves detectors are kilometric Michelson interferometers with additional recycling Fabry–Perot cavities on the arms and ​the addition of two more recycling cavities to enhance their sensitivity, with the particularity that all the mirrors are suspended. In order to control them a new technique, based on the use of auxiliary lasers, has been developed to bring the interferometer to its working point, with all the cavities on their resonance, in an adiabatic way. The implementation of this technique in Advanced Virgo is under preparation and the propagation of a stable laser through a 3-km optical fibre is one of the most problematic issues. A new technique of active phase noise cancellation based on the use of Electro Optical Modulators has been developed, and a first prototype has been successfully tested.

  7. Control of predators in industrial scale microalgae cultures with Pulsed Electric Fields.

    Science.gov (United States)

    Rego, D; Redondo, L M; Geraldes, V; Costa, L; Navalho, J; Pereira, M T

    2015-06-01

    This work describes the utilization of Pulsed Electric Fields to control the protozoan contamination of a microalgae culture, in an industrial 2.7 m(3) microalgae photobioreactor. The contaminated culture was treated with Pulsed Electric Fields, PEF, for 6h with an average of 900 V/cm, 65 μs pulses of 50 Hz. Working with recirculation, all the culture was uniformly exposed to the PEF throughout the assay. The development of the microalgae and protozoan populations was followed and the results showed that PEF is effective on the selective elimination of protozoa from microalgae cultures, inflicting on the protozoa growth halt, death or cell rupture, without affecting microalgae productivity. Specifically, the results show a reduction of the active protozoan population of 87% after 6h treatment and 100% after few days of normal cultivation regime. At the same time, microalgae growth rate remained unaffected. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. TURBOGEN: Computer-controlled vertically oscillating grid system for small-scale turbulence studies on plankton.

    Science.gov (United States)

    Amato, Alberto; Fortini, Stefania; Watteaux, Romain; Diano, Marcello; Espa, Stefania; Esposito, Serena; Ferrante, Maria I; Peters, Francesc; Iudicone, Daniele; Ribera d'Alcalà, Maurizio

    2016-03-01

    In recent years, there has been a renewed interest in the impact of turbulence on aquatic organisms. In response to this interest, a novel instrument has been constructed, TURBOGEN, that generates turbulence in water volumes up to 13 l. TURBOGEN is fully computer controlled, thus, allowing for a high level of reproducibility and for variations of the intensity and characteristics of turbulence during the experiment. The calibration tests, carried out by particle image velocimetry, showed TURBOGEN to be successful in generating isotropic turbulence at the typical relatively low levels of the marine environment. TURBOGEN and its sizing have been devised with the long-term scope of analyzing in detail the molecular responses of plankton to different mixing regimes, which is of great importance in both environmental and biotechnological processes.

  9. Modelling, Optimization and Optimal Control of Small Scale Stirred Tank Bioreactors

    Directory of Open Access Journals (Sweden)

    Mitko Petrov

    2004-10-01

    Full Text Available Models of the mass-transfer in a stirred tank bioreactor depending on general indexes of the processes of aeration and mixing in concrete simplifications of the hydrodynamic structure of the flows are developed. The offered combined model after parameters identification is used for optimization of the parameters of the apparatus construction. The optimization problem is solved by using of the fuzzy sets theory and in this way the unspecified as a result of the model simplification are read. In conclusion an optimal control of a fed-batch fermentation process of E. coli is completed by using Neuro-Dynamic programming. The received results after optimization show a considerable improvement of the mass-transfer indexes and the quantity indexes at the end of the process.

  10. Large-scale controls on potential respiration and denitrification in riverine floodplains.

    Science.gov (United States)

    Welti, Nina; Bondar-Kunze, Elisabeth; Singer, Gabriel; Tritthart, Michael; Zechmeister-Boltenstern, Sophie; Hein, Thomas; Pinay, Gilles

    2012-05-01

    Restoration measures of deteriorated river ecosystems generally aim at increasing the spatial heterogeneity and connectivity of these systems in order to increase biodiversity and ecosystem stability. While this is believed to benefit overall ecological integrity, consequences of such restoration projects on biogeochemical processes per se (i.e. ecosystem functioning) in fluvial systems are rarely considered. We address these issues by evaluating the characteristics of surface water connection between side arms and the main river channel in a former braided river section and the role and degree of connectivity (i.e. duration of surface water connection) on the sediment biogeochemistry. We hypothesized that potential respiration and denitrification would be controlled by the degree of hydrological connectivity, which was increased after floodplain restoration. We measured potential microbial respiration (SIR) and denitrification (DEA) and compared a degraded floodplain section of the Danube River with a reconnected and restored floodplain in the same river section. Re-establishing surface water connection altered the controls on sediment microbial respiration and denitrification ultimately impacting potential microbial activities. Meta-variables were created to characterize the effects of hydrology, morphology, and the available carbon and nutrient pools on potential microbial processing. Mantel statistics and path analysis were performed and demonstrate a hierarchy where the effects of hydrology on the available substrates and microbial processing are mediated by the morphology of the floodplain. In addition, these processes are highest in the least connected sites. Surface water connection, mediated by morphology regulates the potential denitrification rate and the ratio of N2O to N2 emissions, demonstrating the effects of restoration in floodplain systems.

  11. Time Lags in Watershed-Scale Nutrient Transport: An Exploration of Dominant Controls

    Science.gov (United States)

    Basu, N. B.; Van Meter, K. J.

    2016-12-01

    With agricultural intensification, rivers and streams flowing through managed catchments have become delivery channels for excess nutrients, leading to problems of eutrophication and posing risks to drinking water safety. In watersheds around the world, major policy goals have been set to improve water quality, including those in the Water Framework Directive in Europe and the Clean Water Act in the United States. Location-specific water quality goals have also been set by regional working groups, including the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force, the Chesapeake Bay Program, and the Great Lakes Commission. In almost all cases, however, deadlines for achieving water quality goals have been missed, and insufficient improvements have been observed in receiving water bodies. Such apparent failures can be blamed on a variety of factors, including institutional inertia and a lack of funding for needed changes in management. It is our hypothesis, however, that repeated failures to meet water quality-related policy goals are in many cases due to sometimes long lag times between changes in nutrient management and improvements in water quality, and that these lag times can be attributed to the presence of biogeochemical and hydrologic nutrient legacies within the landscape. In the present work we have used the Grand River Watershed (GRW), a heavily agricultural 6800 km2 watershed in Southern Ontario, Canada, as a case study to explore long-term N dynamics and the potential impact of N legacies on water quality. In this work, we developed a 70-year dataset of nitrogen (N) inputs to the GRW and use it to quantify spatial and temporal patterns of legacy nutrient accumulation within the catchment. We then link these patterns of accumulation with 3 decades of stream nutrient concentration data at multiple scales. Results demonstrate a clear decoupling between nutrient inputs and outputs that is suggestive of watershed lag times. A statistical approach

  12. PILOT-AND FULL-SCALE DEMONSTRATION OF ADVANCED MERCURY CONTROL TECHNOLOGIES FOR LIGNITE-FIRED POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Steven A. Benson; Charlene R. Crocker; Kevin C. Galbreath; Jay R. Gunderson; Michael J. Holmes; Jason D. Laumb; Jill M. Mackenzie; Michelle R. Olderbak; John H. Pavlish; Li Yan; Ye Zhuang

    2005-02-01

    The overall objective of the project was to develop advanced innovative mercury control technologies to reduce mercury emissions by 50%-90% in flue gases typically found in North Dakota lignite-fired power plants at costs from one-half to three-quarters of current estimated costs. Power plants firing North Dakota lignite produce flue gases that contain >85% elemental mercury, which is difficult to collect. The specific objectives were focused on determining the feasibility of the following technologies: Hg oxidation for increased Hg capture in dry scrubbers, incorporation of additives and technologies that enhance Hg sorbent effectiveness in electrostatic precipitators (ESPs) and baghouses, the use of amended silicates in lignite-derived flue gases for Hg capture, and the use of Hg adsorbents within a baghouse. The approach to developing Hg control technologies for North Dakota lignites involved examining the feasibility of the following technologies: Hg capture upstream of an ESP using sorbent enhancement, Hg oxidation and control using dry scrubbers, enhanced oxidation at a full-scale power plant using tire-derived fuel and oxidizing catalysts, and testing of Hg control technologies in the Advanced Hybrid{trademark} filter.

  13. Demonstration of Active Power Controls by Utility-Scale PV Power Plant in an Island Grid: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, Vahan; O' Neill, Barbara

    2017-02-01

    The National Renewable Energy Laboratory (NREL), AES, and the Puerto Rico Electric Power Authority conducted a demonstration project on a utility-scale photovoltaic (PV) plant to test the viability of providing important ancillary services from this facility. As solar generation increases globally, there is a need for innovation and increased operational flexibility. A typical PV power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. In this way, it may mitigate the impact of its variability on the grid and contribute to important system requirements more like traditional generators. In 2015, testing was completed on a 20-MW AES plant in Puerto Rico, and a large amount of test data was produced and analyzed that demonstrates the ability of PV power plants to provide various types of new grid-friendly controls. This data showed how active power controls can leverage PV's value from being simply an intermittent energy resource to providing additional ancillary services for an isolated island grid. Specifically, the tests conducted included PV plant participation in automatic generation control, provision of droop response, and fast frequency response.

  14. Large-scale use of mosquito larval source management for malaria control in Africa: a cost analysis

    Directory of Open Access Journals (Sweden)

    Worrall Eve

    2011-11-01

    Full Text Available Abstract Background At present, large-scale use of two malaria vector control methods, long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS is being scaled up in Africa with substantial funding from donors. A third vector control method, larval source management (LSM, has been historically very successful and is today widely used for mosquito control globally, except in Africa. With increasing risk of insecticide resistance and a shift to more exophilic vectors, LSM is now under re-evaluation for use against afro-tropical vector species. Here the costs of this intervention were evaluated. Methods The 'ingredients approach' was used to estimate the economic and financial costs per person protected per year (pppy for large-scale LSM using microbial larvicides in three ecologically diverse settings: (1 the coastal metropolitan area of Dar es Salaam in Tanzania, (2 a highly populated Kenyan highland area (Vihiga District, and (3 a lakeside setting in rural western Kenya (Mbita Division. Two scenarios were examined to investigate the cost implications of using alternative product formulations. Sensitivity analyses on product prices were carried out. Results The results show that for programmes using the same granular formulation larviciding costs the least pppy in Dar es Salaam (US$0.94, approximately 60% more in Vihiga District (US$1.50 and the most in Mbita Division (US$2.50. However, these costs are reduced substantially if an alternative water-dispensable formulation is used; in Vihiga, this would reduce costs to US$0.79 and, in Mbita Division, to US$1.94. Larvicide and staff salary costs each accounted for approximately a third of the total economic costs per year. The cost pppy depends mainly on: (1 the type of formulation required for treating different aquatic habitats, (2 the human population density relative to the density of aquatic habitats and (3 the potential to target the intervention in space and/or time. Conclusion

  15. Large-scale use of mosquito larval source management for malaria control in Africa: a cost analysis.

    Science.gov (United States)

    Worrall, Eve; Fillinger, Ulrike

    2011-11-08

    At present, large-scale use of two malaria vector control methods, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) is being scaled up in Africa with substantial funding from donors. A third vector control method, larval source management (LSM), has been historically very successful and is today widely used for mosquito control globally, except in Africa. With increasing risk of insecticide resistance and a shift to more exophilic vectors, LSM is now under re-evaluation for use against afro-tropical vector species. Here the costs of this intervention were evaluated. The 'ingredients approach' was used to estimate the economic and financial costs per person protected per year (pppy) for large-scale LSM using microbial larvicides in three ecologically diverse settings: (1) the coastal metropolitan area of Dar es Salaam in Tanzania, (2) a highly populated Kenyan highland area (Vihiga District), and (3) a lakeside setting in rural western Kenya (Mbita Division). Two scenarios were examined to investigate the cost implications of using alternative product formulations. Sensitivity analyses on product prices were carried out. The results show that for programmes using the same granular formulation larviciding costs the least pppy in Dar es Salaam (US$0.94), approximately 60% more in Vihiga District (US$1.50) and the most in Mbita Division (US$2.50). However, these costs are reduced substantially if an alternative water-dispensable formulation is used; in Vihiga, this would reduce costs to US$0.79 and, in Mbita Division, to US$1.94. Larvicide and staff salary costs each accounted for approximately a third of the total economic costs per year. The cost pppy depends mainly on: (1) the type of formulation required for treating different aquatic habitats, (2) the human population density relative to the density of aquatic habitats and (3) the potential to target the intervention in space and/or time. Costs for LSM compare favourably with costs for IRS

  16. Lifetime and size of shallow magma bodies controlled by crustal-scale magmatism

    Science.gov (United States)

    Karakas, Ozge; Degruyter, Wim; Bachmann, Olivier; Dufek, Josef

    2017-06-01

    Magmatic processes on Earth govern the mass, energy and chemical transfer between the mantle, crust and atmosphere. To understand magma storage conditions in the crust that ultimately control volcanic activity and growth of continents, an evaluation of the mass and heat budget of the entire crustal column during magmatic episodes is essential. Here we use a numerical model to constrain the physical conditions under which both lower and upper crustal magma bodies form. We find that over long durations of intrusions (greater than 105 to 106 yr), extensive lower crustal mush zones develop, which modify the thermal budget of the upper crust and reduce the flux of magma required to sustain upper crustal magma reservoirs. Our results reconcile physical models of magma reservoir construction and field-based estimates of intrusion rates in numerous volcanic and plutonic localities. Young igneous provinces (less than a few hundred thousand years old) are unlikely to support large upper crustal reservoirs, whereas longer-lived systems (active for longer than 1 million years) can accumulate magma and build reservoirs capable of producing super-eruptions, even with intrusion rates smaller than 10-3 to 10-2 km3 yr-1. Hence, total duration of magmatism should be combined with the magma intrusion rates to assess the capability of volcanic systems to form the largest explosive eruptions on Earth.

  17. Small scale test for seismic response control structure using block & tackle

    Science.gov (United States)

    Zaman, Faisal bin; Suzuki, Yoshiaki; Hayashi, Kazuhiro; Saito, Taiki

    2017-10-01

    An innovative and economic seismic response control system using block and tackle system (hereinafter referred as movable pulley damper system) is under development. In order to clarify the influence of friction between the pulley and the wire, a wire was applied to multiple pulleys and a static force test in which a weight was hung on one side was performed. The frictional force was measured in different test cases by changing the number of loops of the wire and the weight value. If we divide the frictional force by the weight and the number of grooves of pulley, the results show a relatively constant friction coefficient. Then, a dynamic shaking table test using a two story specimen was conducted. Similar to the static test, the frictional force was measured in test cases by changing the number of loops of the wire, the initial tension force of the wire and the amplitude of input sine wave. The obtained friction coefficient was almost the same value of the static test that means the friction coefficient does not change so much between static and dynamic loading conditions.

  18. Demographic profile, Oral Health Impact Profile and Dental Anxiety Scale in patients with chronic periodontitis: a case-control study.

    Science.gov (United States)

    Levin, Liran; Zini, Avraham; Levine, Jonathan; Weiss, Maor; Lev, Ron; Chebath Taub, Daniella; Hai, Avihai; Almoznino, Galit

    2018-01-30

    To examine whether dental anxiety (DA) and oral health-related quality of life (OHRQoL) differ between persons with and those without chronic periodontitis. One-hundred patients with chronic periodontitis and 50 age- and- sex-matched controls were included. Data were collected on the following: demographics; smoking habits; Numerical Rating Scale (NRS) for dental pain assessment; Corah's Dental Anxiety Scale (DAS); Oral Health Impact Profile 14 (OHIP-14); Decayed, Missing and Filled Teeth (DMFT) index; Plaque Index (PI); probing depth (PD); bleeding on probing (BOP); and radiographic bone loss. Patients with chronic periodontitis exhibited a significantly higher percentage of high anxiety and phobia compared with subjects in the control group. Furthermore, patients with chronic periodontitis were statistically significantly more likely to consider themselves as suffering from dental anxiety (68.7% vs. 14.3%, P noise and feeling a foreign object in the mouth. Patients with chronic periodontitis exhibited worse OHIP-14 global scores as well as worse scores in the following individual domains: functional limitation (P = 0.005); physical disability (P = 0.003); psychological disability (P = 0.010); social disability (P = 0.011); and handicap (P = 0.012). Compared with controls, patients with chronic periodontitis had higher levels of dental anxiety and worse OHRQoL. It is important to consider dental anxiety and OHRQoL assessment as an integral component of the evaluation of patients with chronic periodontitis. Communication between dental and behavioral health professionals is needed to implement a multidisciplinary team approach involving behavioural and psychological interventions. © 2018 FDI World Dental Federation.

  19. Unlocking the Physiochemical Controls on Organic Carbon Dynamics from the Soil Pore- to Core-Scale

    Science.gov (United States)

    Smith, A. P.; Tfaily, M. M.; Bond-Lamberty, B. P.; Todd-Brown, K. E.; Bailey, V. L.

    2015-12-01

    The physical organization of soil includes pore networks of varying size and connectivity. These networks control microbial access to soil organic carbon (C) by spatially separating microorganisms and C by both distance and size exclusion. The extent to which this spatially isolated C is vulnerable to microbial transformation under hydrologically dynamic conditions is unknown, and limits our ability to predict the source and sink capacity of soils. We investigated the effects of shifting hydrologic connectivity and soil structure on greenhouse gas C emissions from surface soils collected from the Disney Wilderness Preserve (Florida, USA). We subjected intact soil cores and re-packed homogenized soil cores to simulated groundwater rise or precipitation, monitoring their CO2 and CH4 emissions over 24 hours. Soil pore water was then extracted from each core using different suctions to sample water retained by pore throats of different sizes and then characterized by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Greater respiration rates were observed from homogenized cores compared to intact cores, and from soils wet from below, in which the wetting front is driven by capillary forces, filling fine pores first. This suggests that C located in fine pores may turn over via diffusion processes that lead to the colocation of this C with other resources and microorganisms. Both the complexity and concentration of soluble-C increased with decreasing pore size domains. Pore water extracted from homogenized cores had greater C concentrations than from intact cores, with the greatest concentrations in pore waters sampled from very fine pores, highlighting the importance of soil structure in physically protecting C. These results suggest that the spatial separation of decomposers from C is a key mechanism stabilizing C in these soils. Further research is ongoing to accurately represent this protection mechanism, and the conditions under which it breaks

  20. Serious injury prediction algorithm based on large-scale data and under-triage control.

    Science.gov (United States)

    Nishimoto, Tetsuya; Mukaigawa, Kosuke; Tominaga, Shigeru; Lubbe, Nils; Kiuchi, Toru; Motomura, Tomokazu; Matsumoto, Hisashi

    2017-01-01

    The present study was undertaken to construct an algorithm for an advanced automatic collision notification system based on national traffic accident data compiled by Japanese police. While US research into the development of a serious-injury prediction algorithm is based on a logistic regression algorithm using the National Automotive Sampling System/Crashworthiness Data System, the present injury prediction algorithm was based on comprehensive police data covering all accidents that occurred across Japan. The particular focus of this research is to improve the rescue of injured vehicle occupants in traffic accidents, and the present algorithm assumes the use of an onboard event data recorder data from which risk factors such as pseudo delta-V, vehicle impact location, seatbelt wearing or non-wearing, involvement in a single impact or multiple impact crash and the occupant's age can be derived. As a result, a simple and handy algorithm suited for onboard vehicle installation was constructed from a sample of half of the available police data. The other half of the police data was applied to the validation testing of this new algorithm using receiver operating characteristic analysis. An additional validation was conducted using in-depth investigation of accident injuries in collaboration with prospective host emergency care institutes. The validated algorithm, named the TOYOTA-Nihon University algorithm, proved to be as useful as the US URGENCY and other existing algorithms. Furthermore, an under-triage control analysis found that the present algorithm could achieve an under-triage rate of less than 10% by setting a threshold of 8.3%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Large-scale environmental controls on microbial biofilms in high-alpine streams

    Directory of Open Access Journals (Sweden)

    T. J. Battin

    2004-01-01

    Full Text Available Glaciers are highly responsive to global warming and important agents of landscape heterogeneity. While it is well established that glacial ablation and snowmelt regulate stream discharge, linkage among streams and streamwater geochemistry, the controls of these factors on stream microbial biofilms remain insufficiently understood. We investigated glacial (metakryal, hypokryal, groundwater-fed (krenal and snow-fed (rhithral streams - all of them representative for alpine stream networks - and present evidence that these hydrologic and hydrogeochemical factors differentially affect sediment microbial biofilms. Average microbial biomass and bacterial carbon production were low in the glacial streams, whereas bacterial cell size, biomass, and carbon production were higher in the tributaries, most notably in the krenal stream. Whole-cell in situ fluorescence hybridization revealed reduced detection rates of the Eubacteria and higher abundance of α-Proteobacteria in the glacial stream, a pattern that most probably reflects the trophic status of this ecosystem. Our data suggest low flow during the onset of snowmelt and autumn as a short period (hot moment of favorable environmental conditions with pulsed inputs of allochthonous nitrate and dissolved organic carbon, and with disproportionately high microbial growth. Tributaries are relatively more constant and favorable environments than kryal streams, and serve as possible sources of microbes and organic matter to the main glacial channel during periods (e.g., snowmelt of elevated hydrologic linkage among streams. Ice and snow dynamics - and their impact on the amount and composition of dissolved organic matter - have a crucial impact on stream biofilms, and we thus need to consider microbes and critical hydrological episodes in future models of alpine stream communities.

  2. Costs and consequences of large-scale vector control for malaria

    Directory of Open Access Journals (Sweden)

    Mueller Dirk H

    2008-12-01

    Full Text Available Abstract Background Five large insecticide-treated net (ITN programmes and two indoor residual spraying (IRS programmes were compared using a standardized costing methodology. Methods Costs were measured locally or derived from existing studies and focused on the provider perspective, but included the direct costs of net purchases by users, and are reported in 2005 USD. Effectiveness was estimated by combining programme outputs with standard impact indicators. Findings Conventional ITNs: The cost per treated net-year of protection ranged from USD 1.21 in Eritrea to USD 6.05 in Senegal. The cost per child death averted ranged from USD 438 to USD 2,199 when targeting to children was successful. Long-lasting insecticidal nets (LLIN of five years duration: The cost per treated-net year of protection ranged from USD 1.38 in Eritrea to USD 1.90 in Togo. The cost per child death averted ranged from USD 502 to USD 692. IRS: The costs per person-year of protection for all ages were USD 3.27 in KwaZulu Natal and USD 3.90 in Mozambique. If only children under five years of age were included in the denominator the cost per person-year of protection was higher: USD 23.96 and USD 21.63. As a result, the cost per child death averted was higher than for ITNs: USD 3,933–4,357. Conclusion Both ITNs and IRS are highly cost-effective vector control strategies. Integrated ITN free distribution campaigns appeared to be the most efficient way to rapidly increase ITN coverage. Other approaches were as or more cost-effective, and appeared better suited to "keep-up" coverage levels. ITNs are more cost-effective than IRS for highly endemic settings, especially if high ITN coverage can be achieved with some demographic targeting.

  3. Large-scale environmental controls on microbial biofilms in high-alpine streams

    Science.gov (United States)

    Battin, T. J.; Wille, A.; Psenner, R.; Richter, A.

    Glaciers are highly responsive to global warming and important agents of landscape heterogeneity. While it is well established that glacial ablation and snowmelt regulate stream discharge, linkage among streams and streamwater geochemistry, the controls of these factors on stream microbial biofilms remain insufficiently understood. We investigated glacial (metakryal, hypokryal), groundwater-fed (krenal) and snow-fed (rhithral) streams - all of them representative for alpine stream networks - and present evidence that these hydrologic and hydrogeochemical factors differentially affect sediment microbial biofilms. Average microbial biomass and bacterial carbon production were low in the glacial streams, whereas bacterial cell size, biomass, and carbon production were higher in the tributaries, most notably in the krenal stream. Whole-cell in situ fluorescence hybridization revealed reduced detection rates of the Eubacteria and higher abundance of α-Proteobacteria in the glacial stream, a pattern that most probably reflects the trophic status of this ecosystem. Our data suggest low flow during the onset of snowmelt and autumn as a short period (hot moment) of favorable environmental conditions with pulsed inputs of allochthonous nitrate and dissolved organic carbon, and with disproportionately high microbial growth. Tributaries are relatively more constant and favorable environments than kryal streams, and serve as possible sources of microbes and organic matter to the main glacial channel during periods (e.g., snowmelt) of elevated hydrologic linkage among streams. Ice and snow dynamics - and their impact on the amount and composition of dissolved organic matter - have a crucial impact on stream biofilms, and we thus need to consider microbes and critical hydrological episodes in future models of alpine stream communities.

  4. The Use of Quality Control and Data Mining Techniques for Monitoring Scaled Scores: An Overview. Research Report. ETS RR-12-20

    Science.gov (United States)

    von Davier, Alina A.

    2012-01-01

    Maintaining comparability of test scores is a major challenge faced by testing programs that have almost continuous administrations. Among the potential problems are scale drift and rapid accumulation of errors. Many standard quality control techniques for testing programs, which can effectively detect and address scale drift for small numbers of…

  5. The Continuum of Conflict and Control Relationship Scale (CCC-RS): Psychometrics for a Measure Designed to Discriminate among Types of Intimate Partner Violence

    Science.gov (United States)

    Carlson, Ryan G.; Rogers, Tiffany L.; Wheeler, Naomi J.; Kelchner, Viki; Griffith, Sandy-Ann M.; Liu, Xun

    2017-01-01

    Intimate partner violence (IPV) classifications have treatment implications for couples. This study tested the psychometrics of the Continuum of Conflict and Control Relationship Scale (CCC-RS) and examined differences between violence severity and CCC-RS scales. A sample of 575 low-income, ethnically diverse participants contributed data. Results…

  6. Ecosystem Scale Declines in Elk Recruitment and Population Growth with Wolf Colonization: A Before-After-Control-Impact Approach: e102330

    National Research Council Canada - National Science Library

    David Christianson; Scott Creel

    2014-01-01

    ... reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects...

  7. Robust decentralized hybrid adaptive output feedback fuzzy control for a class of large-scale MIMO nonlinear systems and its application to AHS.

    Science.gov (United States)

    Huang, Yi-Shao; Liu, Wel-Ping; Wu, Min; Wang, Zheng-Wu

    2014-09-01

    This paper presents a novel observer-based decentralized hybrid adaptive fuzzy control scheme for a class of large-scale continuous-time multiple-input multiple-output (MIMO) uncertain nonlinear systems whose state variables are unmeasurable. The scheme integrates fuzzy logic systems, state observers, and strictly positive real conditions to deal with three issues in the control of a large-scale MIMO uncertain nonlinear system: algorithm design, controller singularity, and transient response. Then, the design of the hybrid adaptive fuzzy controller is extended to address a general large-scale uncertain nonlinear system. It is shown that the resultant closed-loop large-scale system keeps asymptotically stable and the tracking error converges to zero. The better characteristics of our scheme are demonstrated by simulations. Copyright © 2014. Published by Elsevier Ltd.

  8. Framework for evaluating the health impact of the scale-up of malaria control interventions on all-cause child mortality in Sub-Saharan Africa

    NARCIS (Netherlands)

    Y. Ye (Yazoume); Eisele, T.P. (Thomas P.); Eckert, E. (Erin); E.L. Korenromp (Eline); Shah, J.A. (Jui A.); Hershey, C.L. (Christine L.); Ivanovich, E. (Elizabeth); Newby, H. (Holly); Carvajal-Velez, L. (Liliana); Lynch, M. (Michael); R. Komatsu (Ryuichi); R.E. Cibulskis (Richard E); Moore, Z. (Zhuzhi); Bhattarai, A. (Achuyt)

    2017-01-01

    textabstractConcerted efforts from national and international partners have scaled up malaria control interventions, including insecticide-treated nets, indoor residual spraying, diagnostics, prompt and effective treatment of malaria cases, and intermittent preventive treatment during pregnancy in

  9. Scale effects on the evapotranspiration estimation over a water-controlled Mediterranean ecosystem and its influence on hydrological modelling

    Science.gov (United States)

    Carpintero, Elisabet; González-Dugo, María P.; José Polo, María; Hain, Christopher; Nieto, Héctor; Gao, Feng; Andreu, Ana; Kustas, William; Anderson, Martha

    2017-04-01

    The integration of currently available satellite data into surface energy balance models can provide estimates of evapotranspiration (ET) with spatial and temporal resolutions determined by sensor characteristics. The use of data fusion techniques may increase the temporal resolution of these estimates using multiple satellites, providing a more frequent ET monitoring for hydrological purposes. The objective of this work is to analyze the effects of pixel resolution on the estimation of evapotranspiration using different remote sensing platforms, and to provide continuous monitoring of ET over a water-controlled ecosystem, the Holm oak savanna woodland known as dehesa. It is an agroforestry system with a complex canopy structure characterized by widely-spaced oak trees combined with crops, pasture and shrubs. The study was carried out during two years, 2013 and 2014, combining ET estimates at different spatial and temporal resolutions and applying data fusion techniques for a frequent monitoring of water use at fine spatial resolution. A global and daily ET product at 5 km resolution, developed with the ALEXI model using MODIS day-night temperature difference (Anderson et al., 2015a) was used as a starting point. The associated flux disaggregation scheme, DisALEXI (Norman et al., 2003), was later applied to constrain higher resolution ET from both MODIS and Landsat 7/8 images. The Climate Forecast System Reanalysis (CFSR) provided the meteorological data. Finally, a data fusion technique, the STARFM model (Gao et al., 2006), was applied to fuse MODIS and Landsat ET maps in order to obtain daily ET at 30 m resolution. These estimates were validated and analyzed at two different scales: at local scale over a dehesa experimental site and at watershed scale with a predominant Mediterranean oak savanna landscape, both located in Southern Spain. Local ET estimates from the modeling system were validated with measurements provided by an eddy covariance tower installed in

  10. Reach-scale cation exchange controls on major ion chemistry of an Antarctic glacial meltwater stream

    Science.gov (United States)

    Gooseff, Michael N.; McKnight, Diane M.; Runkel, Robert L.

    2004-01-01

    McMurdo dry valleys of Antarctica represent the largest of the ice-free areas on the Antarctic continent, containing glaciers, meltwater streams, and closed basin lakes. Previous geochemical studies of dry valley streams and lakes have addressed chemical weathering reactions of hyporheic substrate and geochemical evolution of dry valley surface waters. We examine cation transport and exchange reactions during a stream tracer experiment in a dry valley glacial meltwater stream. The injection solution was composed of dissolved Li+, Na+, K+, and Cl-. Chloride behaved conservatively in this stream, but Li+, Na+, and K+ were reactive to varying degrees. Mass balance analysis indicates that relative to Cl-, Li+ and K+ were taken up in downstream transport and Na+ was released. Simulations of conservative and reactive (first-order uptake or generation) solute transport were made with the OTIS (one-dimensional solute transport with inflow and storage) model. Among the four experimental reaches of Green Creek, solute transport simulations reveal that Li+ was removed from stream water in all four reaches, K+ was released in two reaches, taken up in one reach, and Na+ was released in all four reaches. Hyporheic sediments appear to be variable with uptake of Li+ in two reaches, uptake of K+ in one reach, release of K+ in two reaches, and uptake of Na+ in one reach. Mass balances of the conservative and reactive simulations show that from 1.05 to 2.19 moles of Li+ was adsorbed per reach, but less than 0.3 moles of K+ and less than 0.9 moles of Na+ were released per reach. This suggests that either (1) exchange of another ion which was not analyzed in this experiment or (2) that both ion exchange and sorption control inorganic solute transport. The elevated cation concentrations introduced during the experiment are typical of initial flows in each flow season, which flush accumulated dry salts from the streambed. We propose that the bed sediments (which compose the hyporheic

  11. Carbon sequestration in Southeast Asian tropical peatlands over the Holocene period: large-scale hydrological controls

    Science.gov (United States)

    Dommain, R.; Couwenberg, J.; Cobb, A.; Gandois, L.; Kai, F.; Su'ut, N.; Abu Salim, K.; Harvey, C. F.; Glaser, P. H.; Joosten, H.

    2012-12-01

    support the hypothesis that the water table elevation and not temperature is the primary control of the carbon balance of tropical peatlands. The period of fastest peatland expansion and highest CAR was the wettest period in the Holocene with the lowest hydraulic gradient imposed by the highstand in sea-level. The period with the lowest and nearly quiescent CAR was associated with higher drought stress and a steeper hydraulic gradient, implying lower water tables. The remarkably high carbon sequestration rates of Southeast Asian peatlands can be explained by the high production of woody biomass throughout the year under waterlogged conditions. Woody organic matter is principally resistant to decomposition in an anaerobic setting causing rapid rates of carbon accumulation as long as the water table remains high. Increased drought severity, possibly in association with changes in the El Niño-Southern Oscillation under a warmer future climate could potentially switch Southeast Asian carbon sequestering peatlands to carbon sources.

  12. Reduced Order Modeling for Prediction and Control of Large-Scale Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Kalashnikova, Irina [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Computational Mathematics; Arunajatesan, Srinivasan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Aerosciences Dept.; Barone, Matthew Franklin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Aerosciences Dept.; van Bloemen Waanders, Bart Gustaaf [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Uncertainty Quantification and Optimization Dept.; Fike, Jeffrey A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Component Science and Mechanics Dept.

    2014-05-01

    This report describes work performed from June 2012 through May 2014 as a part of a Sandia Early Career Laboratory Directed Research and Development (LDRD) project led by the first author. The objective of the project is to investigate methods for building stable and efficient proper orthogonal decomposition (POD)/Galerkin reduced order models (ROMs): models derived from a sequence of high-fidelity simulations but having a much lower computational cost. Since they are, by construction, small and fast, ROMs can enable real-time simulations of complex systems for onthe- spot analysis, control and decision-making in the presence of uncertainty. Of particular interest to Sandia is the use of ROMs for the quantification of the compressible captive-carry environment, simulated for the design and qualification of nuclear weapons systems. It is an unfortunate reality that many ROM techniques are computationally intractable or lack an a priori stability guarantee for compressible flows. For this reason, this LDRD project focuses on the development of techniques for building provably stable projection-based ROMs. Model reduction approaches based on continuous as well as discrete projection are considered. In the first part of this report, an approach for building energy-stable Galerkin ROMs for linear hyperbolic or incompletely parabolic systems of partial differential equations (PDEs) using continuous projection is developed. The key idea is to apply a transformation induced by the Lyapunov function for the system, and to build the ROM in the transformed variables. It is shown that, for many PDE systems including the linearized compressible Euler and linearized compressible Navier-Stokes equations, the desired transformation is induced by a special inner product, termed the “symmetry inner product”. Attention is then turned to nonlinear conservation laws. A new transformation and corresponding energy-based inner product for the full nonlinear compressible Navier

  13. Assessing Impact of Large-Scale Distributed Residential HVAC Control Optimization on Electricity Grid Operation and Renewable Energy Integration

    Science.gov (United States)

    Corbin, Charles D.

    Demand management is an important component of the emerging Smart Grid, and a potential solution to the supply-demand imbalance occurring increasingly as intermittent renewable electricity is added to the generation mix. Model predictive control (MPC) has shown great promise for controlling HVAC demand in commercial buildings, making it an ideal solution to this problem. MPC is believed to hold similar promise for residential applications, yet very few examples exist in the literature despite a growing interest in residential demand management. This work explores the potential for residential buildings to shape electric demand at the distribution feeder level in order to reduce peak demand, reduce system ramping, and increase load factor using detailed sub-hourly simulations of thousands of buildings coupled to distribution power flow software. More generally, this work develops a methodology for the directed optimization of residential HVAC operation using a distributed but directed MPC scheme that can be applied to today's programmable thermostat technologies to address the increasing variability in electric supply and demand. Case studies incorporating varying levels of renewable energy generation demonstrate the approach and highlight important considerations for large-scale residential model predictive control.

  14. Gram-scale synthesis of silica nanotubes with controlled aspect ratios by templating of nickel-hydrazine complex nanorods.

    Science.gov (United States)

    Gao, Chuanbo; Lu, Zhenda; Yin, Yadong

    2011-10-04

    We have developed a robust method for the synthesis of silica nanotubes with controlled aspect ratios on a large scale by templating against rod-like nanocrystals. Crystalline nanorods of a nickel-hydrazine complex are first formed in reverse micelles by surfactant capping on side facets, and subsequent silica coating and selective etching give rise to silica nanotubes of high uniformity and yield. The length of the silica nanotubes is tunable in the range 37-340 nm and can reach as long as micrometers. Control of the length is conveniently achieved by tuning the hydrazine/nickel ratio, which affects the growth kinetics of the nanocrystal templates. The inner diameter of the silica nanotubes can be adjusted in the range 10-20 nm by choosing different surfactants. This method is unique in utilizing reverse micelles as discrete nanoscale reactors for the growth of nanocrystals, allowing for precise control of the features of the nanotubes and opening up new opportunities in the synthesis of novel anisotropic nanomaterials, construction of nanodevices, and potential drug delivery applications. © 2011 American Chemical Society

  15. Examination of the validity and reliability of the French version of the Brief Self-Control Scale.

    Science.gov (United States)

    Brevers, Damien; Foucart, Jennifer; Verbanck, Paul; Turel, Ofir

    2017-10-01

    This study aims to develop and to validate a French version of the Brief Self-Control Scale (BSCS; Tangney et al., 2004). This instrument is usually applied as a unidimensional self-report measure for assessing trait self-control, which captures one's dispositional ability to resist short-term temptation in order to reach more valuable long-term goals. Data were collected from two independent samples of French-speaking individuals (n1 = 287; n2 = 160). Results indicated that the French version of the BSCS can be treated as unidimensional, like the original questionnaire. Data also showed consistent acceptable reliability and reasonable test-retest stability. Acceptable external validity of constructs was supported by relationships with self-reported measures of impulsivity (UPPS), including urgency, lack of premeditation, and lack of perseverance. Overall, the findings suggest that the average score of the French version of the BSCS is a viable option for assessing trait self-control in French speaking populations.

  16. Scale-up of community-based malaria control can be achieved without degrading community health workers' service quality: the Village Malaria Worker project in Cambodia

    Directory of Open Access Journals (Sweden)

    Yasuoka Junko

    2012-01-01

    Full Text Available Abstract Background Malaria control has been scaled up in many developing countries in their efforts to achieve the Millennium Development Goals. Cambodia recently scaled up their Village Malaria Worker (VMW project by substantially increasing the number of VMWs and expanding the project's health services to include treatment of fever, diarrhoea, and Acute Respiratory Infections (ARI in children under five. This study examined if the scale-up interfered with VMWs' service quality, actions, and knowledge of malaria control, and analysed VMWs' overall achievements and perceptions of the newly added health services. Methods Structured interviews were conducted pre scale-up in February-March 2008 with 251 VMWs and post scale-up in July-August 2010 with 252 VMWs. Comparing the pre and post scale-up survey results (n = 195, changes were examined in terms of VMWs' 1 service quality, 2 malaria prevention and vector control actions, and 3 knowledge of malaria epidemiology and vector ecology. In addition, VMWs' newly added health services were descriptively analysed based on the post scale-up survey (n = 252. Results VMWs' service quality and actions significantly improved overall during the scale-up of the VMW project (mean index score: +0.805, p p p Conclusions The Cambodian experience clearly demonstrated that a nationwide scale-up of community-based malaria control can be achieved without degrading community health workers' service quality. The government's strategy to expand VMWs' health services, while providing sufficient training to maintain the quality of their original malaria control services, could have contributed to the improvement of VMW's service quality, actions, and knowledge in spite of the rapid scale-up of the project.

  17. Modeling and Coordinated Control Strategy of Large Scale Grid-Connected Wind/Photovoltaic/Energy Storage Hybrid Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Lingguo Kong

    2015-01-01

    Full Text Available An AC-linked large scale wind/photovoltaic (PV/energy storage (ES hybrid energy conversion system for grid-connected application was proposed in this paper. Wind energy conversion system (WECS and PV generation system are the primary power sources of the hybrid system. The ES system, including battery and fuel cell (FC, is used as a backup and a power regulation unit to ensure continuous power supply and to take care of the intermittent nature of wind and photovoltaic resources. Static synchronous compensator (STATCOM is employed to support the AC-linked bus voltage and improve low voltage ride through (LVRT capability of the proposed system. An overall power coordinated control strategy is designed to manage real-power and reactive-power flows among the different energy sources, the storage unit, and the STATCOM system in the hybrid system. A simulation case study carried out on Western System Coordinating Council (WSCC 3-machine 9-bus test system for the large scale hybrid energy conversion system has been developed using the DIgSILENT/Power Factory software platform. The hybrid system performance under different scenarios has been verified by simulation studies using practical load demand profiles and real weather data.

  18. Reversible 2D Phase Transition Driven By an Electric Field: Visualization and Control on the Atomic Scale.

    Science.gov (United States)

    Wortmann, B; van Vörden, D; Graf, P; Robles, R; Abufager, P; Lorente, N; Bobisch, C A; Möller, R

    2016-01-13

    We report on a reversible structural phase transition of a two-dimensional system that can be locally induced by an external electric field. Two different structural configurations may coexist within a CO monolayer on Cu(111). The balance between the two phases can be shifted by an external electric field, causing the domain boundaries to move, increasing the area of the favored phase controllable both in location and size. If the field is further enhanced new domains nucleate. The arrangement of the CO molecules on the Cu surface is observed in real time and real space with atomic resolution while the electric field driving the phase transition is easily varied over a broad range. Together with the well-known molecular manipulation of CO adlayers, our findings open exciting prospects for combining spontaneous long-range order with man-made CO structures such as "molecule cascades" or "molecular graphene". Our new manipulation mode permits us to bridge the gap between fundamental concepts and the fabrication of arbitrary atomic patterns in large scale, by providing unprecedented insight into the physics of structural phase transitions on the atomic scale.

  19. Preferred roles in treatment decision making among patients with cancer: a pooled analysis of studies using the Control Preferences Scale.

    Science.gov (United States)

    Singh, Jasvinder A; Sloan, Jeff A; Atherton, Pamela J; Smith, Tenbroeck; Hack, Thomas F; Huschka, Mashele M; Rummans, Teresa A; Clark, Matthew M; Diekmann, Brent; Degner, Lesley F

    2010-09-01

    To collect normative data, assess differences between demographic groups, and indirectly compare US and Canadian medical systems relative to patient expectations of involvement in cancer treatment decision making. Meta-analysis. Individual patient data were compiled across 6 clinical studies among 3491 patients with cancer who completed the 2-item Control Preferences Scale indicating the roles they preferred versus actually experienced in treatment decision making. The roles in treatment decision making that patients preferred were 26% active, 49% collaborative, and 25% passive. The roles that patients reported actually experiencing were 30% active, 34% collaborative, and 36% passive. Roughly 61% of patients reported having their preferred role; only 6% experienced extreme discordance between their preferred versus actual roles. More men than women (66% vs 60%, P = .001) and more US patients than Canadian patients (84% vs 54%, P women than men reported taking a passive role (40% vs 24%, P communication styles into treatment plans.

  20. Validation of the trait anxiety scale for state-trait anxiety inventory in suicide victims and living controls of Chinese rural youths.

    Science.gov (United States)

    Zhang, Jie; Gao, Qi

    2012-01-01

    This study evaluated the validation of STAI Trait-Anxiety Scale in suicide cases and community living controls in rural China. The participants were 392 suicides and 416 controls. Cronbach's Alpha was computed to evaluate the internal consistency. The Spearman Correlation Coefficient between Trait-Anxiety Scale and other instrument was calculated to evaluate the external validity, and the Exploratory Factor Analysis was used to evaluate the construct validity. The results showed the Cronbach's Alpha was .891 and .787 respectively in case and control groups. Most of the correlations between instruments were significant. We found 2 factors in cases and 3 factors in controls. We could cautiously infer that the Trait Anxiety Scale was an adequate tool to measure trait anxiety through proxy data in suicide victims and living controls in rural China.

  1. Using Distributed Fiber Optic Sensing to Monitor Large Scale Permafrost Transitions: Preliminary Results from a Controlled Thaw Experiment

    Science.gov (United States)

    Ajo Franklin, J. B.; Wagner, A. M.; Lindsey, N.; Dou, S.; Bjella, K.; Daley, T. M.; Freifeld, B. M.; Ulrich, C.; Gelvin, A.; Morales, A.; James, S. R.; Saari, S.; Ekblaw, I.; Wood, T.; Robertson, M.; Martin, E. R.

    2016-12-01

    In a warming world, permafrost landscapes are being rapidly transformed by thaw, yielding surface subsidence and groundwater flow alteration. The same transformations pose a threat to arctic infrastructure and can induce catastrophic failure of the roads, runways, and pipelines on which human habitation depends. Scalable solutions to monitoring permafrost thaw dynamics are required to both quantitatively understand biogeochemical feedbacks as well as to protect built infrastructure from damage. Unfortunately, permafrost alteration happens over the time scale of climate change, years to decades, a decided challenge for testing new sensing technologies in a limited context. One solution is to engineer systems capable of rapidly thawing large permafrost units to allow short duration experiments targeting next-generation sensing approaches. We present preliminary results from a large-scale controlled permafrost thaw experiment designed to evaluate the utility of different geophysical approaches for tracking the cause, precursors, and early phases of thaw subsidence. We focus on the use of distributed fiber optic sensing for this challenge and deployed distributed temperature (DTS), strain (DSS), and acoustic (DAS) sensing systems in a 2D array to detect thaw signatures. A 10 x 15 x 1 m section of subsurface permafrost was heated using an array of 120 downhole heaters (60 w) at an experimental site near Fairbanks, AK. Ambient noise analysis of DAS datasets collected at the plot, coupled to shear wave inversion, was utilized to evaluate changes in shear wave velocity associated with heating and thaw. These measurements were confirmed by seismic surveys collected using a semi-permanent orbital seismic source activated on a daily basis. Fiber optic measurements were complemented by subsurface thermistor and thermocouple arrays, timelapse total station surveys, LIDAR, secondary seismic measurements (geophone and broadband recordings), timelapse ERT, borehole NMR, soil

  2. Novel probabilistic and distributed algorithms for guidance, control, and nonlinear estimation of large-scale multi-agent systems

    Science.gov (United States)

    Bandyopadhyay, Saptarshi

    Multi-agent systems are widely used for constructing a desired formation shape, exploring an area, surveillance, coverage, and other cooperative tasks. This dissertation introduces novel algorithms in the three main areas of shape formation, distributed estimation, and attitude control of large-scale multi-agent systems. In the first part of this dissertation, we address the problem of shape formation for thousands to millions of agents. Here, we present two novel algorithms for guiding a large-scale swarm of robotic systems into a desired formation shape in a distributed and scalable manner. These probabilistic swarm guidance algorithms adopt an Eulerian framework, where the physical space is partitioned into bins and the swarm's density distribution over each bin is controlled using tunable Markov chains. In the first algorithm - Probabilistic Swarm Guidance using Inhomogeneous Markov Chains (PSG-IMC) - each agent determines its bin transition probabilities using a time-inhomogeneous Markov chain that is constructed in real-time using feedback from the current swarm distribution. This PSG-IMC algorithm minimizes the expected cost of the transitions required to achieve and maintain the desired formation shape, even when agents are added to or removed from the swarm. The algorithm scales well with a large number of agents and complex formation shapes, and can also be adapted for area exploration applications. In the second algorithm - Probabilistic Swarm Guidance using Optimal Transport (PSG-OT) - each agent determines its bin transition probabilities by solving an optimal transport problem, which is recast as a linear program. In the presence of perfect feedback of the current swarm distribution, this algorithm minimizes the given cost function, guarantees faster convergence, reduces the number of transitions for achieving the desired formation, and is robust to disturbances or damages to the formation. We demonstrate the effectiveness of these two proposed swarm

  3. When to Spray: a Time-Scale Calculus Approach to Controlling the Impact of West Nile Virus

    Directory of Open Access Journals (Sweden)

    Diana Thomas

    2009-12-01

    Full Text Available West Nile Virus (WNV made its initial appearance in the New York City (NYC metropolitan area in 1999 and was implicated in cases of human encephalitis and the extensive mortality in crows (Corvus sp. and other avian species. Mosquitoes were found to be the primary vectors and NYC's current policy on control strategies involved an eradication program that depends on the synchronicity of the summer mosquito population's increases with the occurrence of cases in humans. The purpose of this paper is to investigate whether this is the most effective control strategy because past mathematical models assumed discrete behavior that is modeled by difference equations for a single summer season was most important to the virus's life cycle. However, both surviving mosquito eggs and surviving migratory birds incubate the virus during the winter, leading to a continuation of infections in the following warmer spring and summer when the birds return and the eggs hatch. Additionally, the virulence of WNV has been observed to fluctuate with changes in temperature toward warmer conditions. Models are required that account for these multi-seasonal dynamics and time-scale calculus is a newly developed method for resolving the behavior of systems that exhibit both discrete and continuous behavior. We found that, although the static states of the new temperature delay model are no different from older models, simulations indicate that the rate of the infection is affected by avian recovery at a lower temperature threshold. Consequently, eradication strategies should consider that controlling mosquitoes during the fall when colder temperatures occur would cause a fast and efficient drop to a disease-free state. This could prove rather more effective than mosquito control in the warmer months.

  4. Electroless Deposition and Nanolithography Can Control the Formation of Materials at the Nano-Scale for Plasmonic Applications

    Directory of Open Access Journals (Sweden)

    Maria Laura Coluccio

    2014-03-01

    Full Text Available The new revolution in materials science is being driven by our ability to manipulate matter at the molecular level to create structures with novel functions and properties. The aim of this paper is to explore new strategies to obtain plasmonic metal nanostructures through the combination of a top down method, that is electron beam lithography, and a bottom up technique, that is the chemical electroless deposition. This technique allows a tight control over the shape and size of bi- and three-dimensional metal patterns at the nano scale. The resulting nanostructures can be used as constituents of Surface Enhanced Raman Spectroscopy (SERS substrates, where the electromagnetic field is strongly amplified. Our results indicate that, in electroless growth, high quality metal nanostructures with sizes below 50 nm may be easily obtained. These findings were explained within the framework of a diffusion limited aggregation (DLA model, that is a simulation model that makes it possible to decipher, at an atomic level, the rules governing the evolution of the growth front; moreover, we give a description of the physical mechanisms of growth at a basic level. In the discussion, we show how these findings can be utilized to fabricate dimers of silver nanospheres where the size and shape of those spheres is controlled with extreme precision and can be used for very large area SERS substrates and nano-optics, for single molecule detection.

  5. Drug loaded and ethylcellulose coated mesoporous silica for controlled drug release prepared using a pilot scale fluid bed system.

    Science.gov (United States)

    Hacene, Youcef Chakib; Singh, Abhishek; Van den Mooter, Guy

    2016-06-15

    The goal of this study was to test the feasibility to load non-ordered, non-spherical mesoporous silica with the model drug paracetamol, and subsequently coat the loaded particles using one single pilot scale fluid bed system equipped with a Wurster insert. Mesoporous silica particles (Davisil(®)) with a size ranging from 310 to 500μm and an average pore diameter of 15nm were loaded with paracetamol to 18.8% drug content. Subsequently, loaded cores were coated with ethylcellulose to obtain controlled drug release. Coating processing variables were varied following a full factorial design and their effect on drug release was assessed. Increasing coating solution feed rate and decreasing fluidizing air temperature were found to increase drug release rates. Increasing pore former level and decreasing coating level were found to increase drug release rates. The release medium's osmolality was varied using different sodium chloride concentrations, which was found to affect drug release rates. The results of this study clearly indicate the potential of non-ordered, non-spherical mesoporous silica as a reservoir carrier for the controlled release of drugs. Although non-spherical, we were able to reproducibly coat this carrier using a bottom spray fluid bed system. However, a major hurdle that needs to be tackled is the attrition the material suffers from during fluid bed processing. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Distributed Model Predictive Control over Multiple Groups of Vehicles in Highway Intelligent Space for Large Scale System

    Directory of Open Access Journals (Sweden)

    Tang Xiaofeng

    2014-01-01

    Full Text Available The paper presents the three time warning distances for solving the large scale system of multiple groups of vehicles safety driving characteristics towards highway tunnel environment based on distributed model prediction control approach. Generally speaking, the system includes two parts. First, multiple vehicles are divided into multiple groups. Meanwhile, the distributed model predictive control approach is proposed to calculate the information framework of each group. Each group of optimization performance considers the local optimization and the neighboring subgroup of optimization characteristics, which could ensure the global optimization performance. Second, the three time warning distances are studied based on the basic principles used for highway intelligent space (HIS and the information framework concept is proposed according to the multiple groups of vehicles. The math model is built to avoid the chain avoidance of vehicles. The results demonstrate that the proposed highway intelligent space method could effectively ensure driving safety of multiple groups of vehicles under the environment of fog, rain, or snow.

  7. Biological and physical controls in the Southern Ocean on past millennial-scale atmospheric CO2 changes.

    Science.gov (United States)

    Gottschalk, Julia; Skinner, Luke C; Lippold, Jörg; Vogel, Hendrik; Frank, Norbert; Jaccard, Samuel L; Waelbroeck, Claire

    2016-05-17

    Millennial-scale climate changes during the last glacial period and deglaciation were accompanied by rapid changes in atmospheric CO2 that remain unexplained. While the role of the Southern Ocean as a 'control valve' on ocean-atmosphere CO2 exchange has been emphasized, the exact nature of this role, in particular the relative contributions of physical (for example, ocean dynamics and air-sea gas exchange) versus biological processes (for example, export productivity), remains poorly constrained. Here we combine reconstructions of bottom-water [O2], export production and (14)C ventilation ages in the sub-Antarctic Atlantic, and show that atmospheric CO2 pulses during the last glacial- and deglacial periods were consistently accompanied by decreases in the biological export of carbon and increases in deep-ocean ventilation via southern-sourced water masses. These findings demonstrate how the Southern Ocean's 'organic carbon pump' has exerted a tight control on atmospheric CO2, and thus global climate, specifically via a synergy of both physical and biological processes.

  8. Electroless deposition and nanolithography can control the formation of materials at the nano-scale for plasmonic applications

    KAUST Repository

    Coluccio, Maria Laura

    2014-03-27

    The new revolution in materials science is being driven by our ability to manipulate matter at the molecular level to create structures with novel functions and properties. The aim of this paper is to explore new strategies to obtain plasmonic metal nanostructures through the combination of a top down method, that is electron beam lithography, and a bottom up technique, that is the chemical electroless deposition. This technique allows a tight control over the shape and size of bi- and three-dimensional metal patterns at the nano scale. The resulting nanostructures can be used as constituents of Surface Enhanced Raman Spectroscopy (SERS) substrates, where the electromagnetic field is strongly amplified. Our results indicate that, in electroless growth, high quality metal nanostructures with sizes below 50 nm may be easily obtained. These findings were explained within the framework of a diffusion limited aggregation (DLA) model, that is a simulation model that makes it possible to decipher, at an atomic level, the rules governing the evolution of the growth front; moreover, we give a description of the physical echanisms of growth at a basic level. In the discussion, we show how these findings can be utilized to fabricate dimers of silver nanospheres where the size and shape of those spheres is controlled with extreme precision and can be used for very large area SERS substrates and nano-optics, for single molecule detection. 2014 by the authors; licensee MDPI, Basel, Switzerland.

  9. A New Hybrid Control Architecture to Attenuate Large Horizontal Wind Disturbance for a Small-Scale Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Xiaorui Zhu

    2012-07-01

    Full Text Available This paper presents a novel method to attenuate large horizontal wind disturbance for a small-scale unmanned autonomous helicopter combining wind tunnel-based experimental data and a backstepping algorithm. Large horizontal wind disturbance is harmful to autonomous helicopters, especially to small ones because of their low inertia and the high cross-coupling effects among the multiple inputs. In order to achieve more accurate and faster attenuation of large wind disturbance, a new hybrid control architecture is proposed to take advantage of the direct force/moment compensation based on the wind tunnel experimental data. In this architecture, large horizontal wind disturbance is treated as an additional input to the control system instead of a small perturbation around the equilibrium state. A backstepping algorithm is then designed to guarantee the stable convergence of the helicopter to the desired position. The proposed technique is finally evaluated in simulation on the platform, HIROBO Eagle, compared with a traditional wind velocity compensation method.

  10. Quality-controlled small-scale production of a well-defined bacteriophage cocktail for use in human clinical trials.

    Directory of Open Access Journals (Sweden)

    Maya Merabishvili

    Full Text Available We describe the small-scale, laboratory-based, production and quality control of a cocktail, consisting of exclusively lytic bacteriophages, designed for the treatment of Pseudomonas aeruginosa and Staphylococcus aureus infections in burn wound patients. Based on successive selection rounds three bacteriophages were retained from an initial pool of 82 P. aeruginosa and 8 S. aureus bacteriophages, specific for prevalent P. aeruginosa and S. aureus strains in the Burn Centre of the Queen Astrid Military Hospital in Brussels, Belgium. This cocktail, consisting of P. aeruginosa phages 14/1 (Myoviridae and PNM (Podoviridae and S. aureus phage ISP (Myoviridae was produced and purified of endotoxin. Quality control included Stability (shelf life, determination of pyrogenicity, sterility and cytotoxicity, confirmation of the absence of temperate bacteriophages and transmission electron microscopy-based confirmation of the presence of the expected virion morphologic particles as well as of their specific interaction with the target bacteria. Bacteriophage genome and proteome analysis confirmed the lytic nature of the bacteriophages, the absence of toxin-coding genes and showed that the selected phages 14/1, PNM and ISP are close relatives of respectively F8, phiKMV and phage G1. The bacteriophage cocktail is currently being evaluated in a pilot clinical study cleared by a leading Medical Ethical Committee.

  11. Personality traits in established schizophrenia: aspects of usability and differences between patients and controls using the Swedish universities Scales of Personality.

    Science.gov (United States)

    Fagerberg, Tomas; Söderman, Erik; Gustavsson, J Petter; Agartz, Ingrid; Jönsson, Erik G

    2016-08-01

    Personality is considered as an important aspect that can affect symptoms and social function in persons with schizophrenia. The personality questionnaire Swedish universities Scales of Personality (SSP) has not previously been used in psychotic disorder. To investigate if SSP has a similar internal consistency and factor structure in a psychosis population as among healthy controls and if patients with psychotic disorders differ from non-psychotic individuals in their responses to the SSP. Patients with psychotic disorders (n = 107) and healthy controls (n = 119) completed SSP. SSP scores were analyzed for internal consistency and case-control differences by Cronbach's alfa and multiple analysis of covariance, respectively. Internal consistencies among patients were overall similar to that of controls. The patients scored significantly higher in seven (Somatic trait anxiety, Psychic trait anxiety, Stress susceptibility, Lack of assertiveness, Detachment, Embitterment, Mistrust) and lower in three (Physical trait aggression, Verbal trait aggression, Adventure seeking) of the 13 scales of the inventory. In three scales (Impulsiveness, Social desirability and Trait irritability) there was no significant difference between the scoring of patients and healthy controls. The reliability estimates suggest that SSP can be used by patients with psychotic disorders in stable remission. Patients score higher on neuroticism-related scales and lower on aggression-related scales than controls, which is in accordance with earlier studies where other personality inventories were used.

  12. Financial analysis of brucellosis control for small-scale goat farming in the Bajío region, Mexico.

    Science.gov (United States)

    Oseguera Montiel, David; Bruce, Mieghan; Frankena, Klaas; Udo, Henk; van der Zijpp, Akke; Rushton, Jonathan

    2015-03-01

    Brucellosis is an endemic disease in small-scale goat husbandry systems in Mexico. It is a zoonosis and the economic consequences can be large, although estimates are not available for the Mexican goat sector. Our objective was to conduct a financial analysis of brucellosis control in a prominent dairy goat production area of the Bajío region, Mexico. We used three models: (1) a brucellosis transmission model at village flock level (n=1000 head), (2) a flock growth model at smallholder flock level (n=23 head) using output of model 1 and (3) cost-benefit analysis of several brucellosis control scenarios based on output of model 2. Scenarios consisted of test-and-slaughter or vaccination or a combination of both compared to the base situation (no control). The average net present values (NPV) of using vaccination over a 5-year period was 3.8 US$ (90% CI: 1.3-6.6) and 20 US$ (90% CI: 11.3-28.6) over a 10-year period per goat. The average benefit-cost ratios over a 5-year period and 10-year period were 4.3 US$ (90% CI: 2.2-6.9) and 12.3 US$ (90% CI: 7.5-17.3) per goat, respectively. For the total dairy goat population (38,462 head) of the study area (the Bajío of Jalisco and Michoacán) the NPV's over a 5-year and 10-year period were 0.15 million US$ and 0.8 million US$. However, brucellosis prevalence was predicted to remain relatively high at about 12%. Control scenarios with test-and-slaughter predicted to reduce brucellosis prevalence to less than 3%, but this produced a negative NPV over a 5-year period ranging from -31.6 to -11.1 US$ and from -31.1 to 7.5 US$ over a 10-year period. A brucellosis control campaign based on vaccination with full coverage is economically profitable for the goat dairy sector of the region although smallholders would need financial support in case test-and-slaughter is applied to reduce the prevalence more quickly. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach.

    Directory of Open Access Journals (Sweden)

    David Christianson

    Full Text Available The reintroduction of wolves (Canis lupus to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk--Cervus elaphus in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects of wolves on elk recruitment and population dynamics. Recruitment, as measured by the midwinter juvenile∶female ratio, was a strong determinant of elk dynamics, and declined by 35% in elk herds colonized by wolves as annual population growth shifted from increasing to decreasing. Negative effects of population density and winter severity on recruitment, long recognized as important for elk dynamics, were detected in uncolonized elk herds and in wolf-colonized elk herds prior to wolf colonization, but not after wolf colonization. Growing season precipitation and harvest had no detectable effect on recruitment in either wolf treatment or colonization period, although harvest rates of juveniles∶females declined by 37% in wolf-colonized herds. Even if it is assumed that mortality due to predation is completely additive, liberal estimates of wolf predation rates on juvenile elk could explain no more than 52% of the total decline in juvenile∶female ratios in wolf-colonized herds, after accounting for the effects of other limiting factors. Collectively, these long-term, large-scale patterns align well with prior studies that have reported substantial decrease in elk numbers immediately after wolf recolonization, relatively weak additive effects of direct wolf predation on elk survival, and decreased reproduction and recruitment with exposure to predation risk from wolves.

  14. A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort.

    Science.gov (United States)

    Cantarello, Elena; Steck, Claude E; Fontana, Paolo; Fontaneto, Diego; Marini, Lorenzo; Pautasso, Marco

    2010-03-01

    Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species-people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy's regions (average area 15,000 km(2)) and provinces (2,900 km(2)). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population-biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.

  15. A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort

    Science.gov (United States)

    Cantarello, Elena; Steck, Claude E.; Fontana, Paolo; Fontaneto, Diego; Marini, Lorenzo; Pautasso, Marco

    2010-03-01

    Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species-people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km2) and provinces (2,900 km2). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population-biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.

  16. The Psychometric Properties of Attentional Control Scale and Its Relationship with Symptoms of Anxiety and Depression: A Study on Iranian Population

    Directory of Open Access Journals (Sweden)

    Imaneh Abasi

    2017-04-01

    Full Text Available Objectives: The attentional control scale is a self- report questionnaire that assesses individual differences in attentional control. Despite its extensive use, the psychometric properties of the Persian version of the ACS are not well understood. Thus, the present study aimed at investigating the psychometric properties of the attentional control scale and its relationship with symptoms of anxiety and depression in Iranian population.Method: Using quota sampling, we asked a community sample of 524 to respond to Attentional Control Scale, mindfulness, emotion regulation, social anxiety, depression, generalized anxiety, worry, and rumination. SPSS (Version 23 was used for data analysis.Results: Exploratory factor analysis yielded 2 factors of focusing and shifting, which accounted for 30.93% of the total variance. The results of convergent validity revealed that reappraisal, as an emotion regulation strategy and mindfulness facets, had a positive relationship with focusing, shifting, and the total score of the attentional control scale. Furthermore, worry, rumination, depression, generalized anxiety, and social anxiety symptoms all had negative relationships with focusing, rumination, and the total score of the attentional control scale. In addition, the results of incremental validity revealed that focusing, not shifting, uniquely predicted depression and generalized anxiety symptoms. Furthermore, both focusing and shifting uniquely predicted social anxiety symptoms. Test- retest reliability of focusing and shifting was 0.80 and 0. 76, respectively.Conclusions: Attentional control scale has been demonstrated to have acceptable validity and reliability in Iranian population. However, further studies are needed to evaluate other aspects of the ACS like CFA. 

  17. Simulation of Climate Control On Tectonic Mass-transfer In Bivergent Orogenic Wedges ­ Insights From Scaled Sandbox Models.

    Science.gov (United States)

    Hoth, S.; Adam, J.; Kukowski, N.; Oncken, O.

    Orogenic wedges are expressions of dynamic equilibrium between tectonic and grav- itational stresses. Thus, surficial mass transport by climate-driven erosion changes the morphology of, and the state of stress within, the orogenic wedge. Here, we suggest that the orogenic wedge adjusts itself to the new stress conditions, inducing changes in morphology, which may modify the pre-existing drainage pattern, and therefore change also the erosion rate. Depending on the amount of vertical alteration in wedge morphology the regional climate is modified, which again may lead to a different ero- sion rate. The aim of this study is to describe qualitatively and quantitatively how different ero- sion rates and their 2D lateral distribution influences the mass-transport mode in col- lisional orogens, using scaled sandbox-experiments. The advantages of analogue sim- ulation are (i) a more detailed structural resolution, (ii) a direct observation of strain localisation and fault propagation and (iii) an easy way of applying erosion at any given point through time. The models presented here were run in a 2D shearbox with two converging sand lay- ers which build up a bivergent sand-orogen. A thin glass-bead layer which simulates a mid-level detachment was incorporated to allow frontal and basal accretion. Us- ing a vacuum cleaner, incremental erosion, which decreases linearly from the top of the sand-orogen to the toe of either the pro-wedge or retro-wedge, was simulated. A friction-controlled elastic/plastic rheology with strain hardening and softening is used to simulate upper crustal rock deformation. Our aim is to elucidate: (i) The in- fluence of different modes of distribution of erosion rates on the tectonically-driven mass transfer in orogenic belts. (ii) The control of erosion rates on tectonic style in orogenic wedges, i.e. frontal versus basal accretion. (iii) The time and length scales at which climatic and tectonic forces interact. (iv) The way with which such

  18. Evaluation of laboratory-scale in situ capping sediments with purple parent rock to control the eutrophication.

    Science.gov (United States)

    Huang, Xuejiao; Shi, Wenhao; Ni, Jiupai; Li, Zhenlun

    2017-03-01

    In this study, the effectiveness of controlling the eutrophication using purple parent rock to cap the sediments was evaluated in the laboratory scale. Sediments were collected from Sanxikou reservoir (China) in July 2013. Then, three types of purple parent rock (T 1 f, J 3 p, and J 2 s) which are distributed widely in southwest China were used to cap the sediments. Limestone and calcite were used as the contrast group, because they had been reported as effective controls on eutrophication. Then, they were incubated at 20 °C for 46 days. The results indicated that the application of purple parent rock as a barrier material can effectively inhibit the release of nutrient elements in sediments, and the inhibition rates of total nitrogen (TN), total phosphorus (TP), ammonium (NH 4 -N), and nitrate (NO 3 -N) were much better than that of limestone and calcite. Among the three types of purple parent rock, J 3 p exhibited the best inhibitory effect on the release of nitrogen in sediments, and the inhibition efficiency of TN, NH 4 -N, and NO 3 -N was 59.7, 77.6, and 45.1%, respectively. As for T 1 f, it exhibited the best inhibitory effect on the release of TP in sediments with the inhibition rate of 94.4%. Whereas all these capping materials showed weak inhibition on release of organic matter in sediments, and the inhibition efficiencies were less than 20%. Moreover, these treatments could also cause distinct changes in the microbial community in sediments and overlying water, and the contents of TN and TP in all capping materials increased. All results demonstrated that purple parent rock could inhibit the release of nutrient in sediments through mechanical interception, physical adsorption, and chemical absorption as well as changing the microbial activity in the covering layer, sediments, or overlying water.

  19. Advances in compact manufacturing for shape and performance controllability of large-scale components-a review

    Science.gov (United States)

    Qin, Fangcheng; Li, Yongtang; Qi, Huiping; Ju, Li

    2017-01-01

    Research on compact manufacturing technology for shape and performance controllability of metallic components can realize the simplification and high-reliability of manufacturing process on the premise of satisfying the requirement of macro/micro-structure. It is not only the key paths in improving performance, saving material and energy, and green manufacturing of components used in major equipments, but also the challenging subjects in frontiers of advanced plastic forming. To provide a novel horizon for the manufacturing in the critical components is significant. Focused on the high-performance large-scale components such as bearing rings, flanges, railway wheels, thick-walled pipes, etc, the conventional processes and their developing situations are summarized. The existing problems including multi-pass heating, wasting material and energy, high cost and high-emission are discussed, and the present study unable to meet the manufacturing in high-quality components is also pointed out. Thus, the new techniques related to casting-rolling compound precise forming of rings, compact manufacturing for duplex-metal composite rings, compact manufacturing for railway wheels, and casting-extruding continuous forming of thick-walled pipes are introduced in detail, respectively. The corresponding research contents, such as casting ring blank, hot ring rolling, near solid-state pressure forming, hot extruding, are elaborated. Some findings in through-thickness microstructure evolution and mechanical properties are also presented. The components produced by the new techniques are mainly characterized by fine and homogeneous grains. Moreover, the possible directions for further development of those techniques are suggested. Finally, the key scientific problems are first proposed. All of these results and conclusions have reference value and guiding significance for the integrated control of shape and performance in advanced compact manufacturing.

  20. Dry sorbent injection of trona to control acid gases from a pilot-scale coal-fired combustion facility

    Directory of Open Access Journals (Sweden)

    Tiffany L. B. Yelverton

    2016-01-01

    Full Text Available  Gaseous and particulate emissions from the combustion of coal have been associated with adverse effects on human and environmental health, and have for that reason been subject to regulation by federal and state governments. Recent regulations by the United States Environmental Protection Agency have further restricted the emissions of acid gases from electricity generating facilities and other industrial facilities, and upcoming deadlines are forcing industry to consider both pre- and post-combustion controls to maintain compliance. As a result of these recent regulations, dry sorbent injection of trona to remove acid gas emissions (e.g. HCl, SO2, and NOx from coal combustion, specifically 90% removal of HCl, was the focus of the current investigation. Along with the measurement of HCl, SO2, and NOx, measurements of particulate matter (PM, elemental (EC, and organic carbon (OC were also accomplished on a pilot-scale coal-fired combustion facility. Gaseous and particulate emissions from a coal-fired combustor burning bituminous coal and using dry sorbent injection were the focus of the current study. From this investigation it was shown that high levels of trona were needed to achieve the goal of 90% HCl removal, but with this increased level of trona injection the ESP and BH were still able to achieve greater than 95% fine PM control. In addition to emissions reported, measurement of acid gases by standard EPA methods were compared to those of an infrared multi-component gas analyzer. This comparison revealed good correlation for emissions of HCl and SO2, but poor correlation in the measurement of NOx emissions.

  1. Large-scale recording of thalamocortical circuits: in vivo electrophysiology with the two-dimensional electronic depth control silicon probe

    Science.gov (United States)

    Fiáth, Richárd; Beregszászi, Patrícia; Horváth, Domonkos; Wittner, Lucia; Aarts, Arno A. A.; Ruther, Patrick; Neves, Hercules P.; Bokor, Hajnalka; Acsády, László

    2016-01-01

    Recording simultaneous activity of a large number of neurons in distributed neuronal networks is crucial to understand higher order brain functions. We demonstrate the in vivo performance of a recently developed electrophysiological recording system comprising a two-dimensional, multi-shank, high-density silicon probe with integrated complementary metal-oxide semiconductor electronics. The system implements the concept of electronic depth control (EDC), which enables the electronic selection of a limited number of recording sites on each of the probe shafts. This innovative feature of the system permits simultaneous recording of local field potentials (LFP) and single- and multiple-unit activity (SUA and MUA, respectively) from multiple brain sites with high quality and without the actual physical movement of the probe. To evaluate the in vivo recording capabilities of the EDC probe, we recorded LFP, MUA, and SUA in acute experiments from cortical and thalamic brain areas of anesthetized rats and mice. The advantages of large-scale recording with the EDC probe are illustrated by investigating the spatiotemporal dynamics of pharmacologically induced thalamocortical slow-wave activity in rats and by the two-dimensional tonotopic mapping of the auditory thalamus. In mice, spatial distribution of thalamic responses to optogenetic stimulation of the neocortex was examined. Utilizing the benefits of the EDC system may result in a higher yield of useful data from a single experiment compared with traditional passive multielectrode arrays, and thus in the reduction of animals needed for a research study. PMID:27535370

  2. An analysis of the use of electrical power measurements for process control in large-scale stirred vessels

    Energy Technology Data Exchange (ETDEWEB)

    Hjorth, S.; Karlsson, L. [ABS Pump Peroduction AB SCABA Agitators, Taby (Sweden); Friberg, P. [Telemark Technological Research and Development Centre, Porsgrunn (Norway); Boon, L. [Birmingham Univ., (United Kingdom)

    2000-12-01

    Given that the direct measurement of the power transmitted via an agitator shaft is expensive as well as difficult to carry out, substitute measures such as inferring the transmitted power from a measurement of the electric power needed to operate the agitator motor, are frequently used. Although the accuracy of the measurement is highly inaccurate (less than five per cent accuracy), because of its relative simplicity and low cost, the technique is considered suitable for continuous monitoring of the power used by agitators in large-scale stirred vessels used in industrial processes. This paper describes a measurement method involving the use of a Wattmeter with a magnetic AC current probe fitted to the agitator. The major drawback is that for maximum accuracy the method needs to be calibrated which can be both tricky and cumbersome in all, except new installations. As an alternative, these authors suggest that if the speed control unit is close to being sinusoidal, accuracy levels of up to about 10 per cent can be achieved over a large range of torque and rpm values by accepting the manufacturer's estimate of efficiency. Examples of measurement results using various measurement techniques are discussed. 8 refs., 2 tabs., 6 figs.

  3. Performance of a pilot-scale biotrickling filter in controlling the volatile organic compound emissions in a furniture manufacturing facility.

    Science.gov (United States)

    Martínez-Soria, Vicente; Gabaldón, Carmen; Penya-Roja, Josep M; Palau, Jordi; Alvarez-Hornos, F Javier; Sempere, Feliu; Soriano, Carlos

    2009-08-01

    A 0.75-m3 pilot-scale biotrickling filter was run for over 1 yr in a Spanish furniture company to evaluate its performance in the removal of volatile organic compounds (VOCs) contained in the emission of two different paint spray booths. The first one was an open front booth used to manually paint furniture, and the second focus was an automatically operated closed booth operated to paint pieces of furniture. In both cases, the VOC emissions were very irregular, with rapid and extreme fluctuations. The pilot plant was operated at an empty bed residence time (EBRT) ranging from 10 to 40 sec, and good removal efficiencies of VOCs were usually obtained. When a buffering activated carbon prefilter was installed, the system performance was improved considerably, so a much better compliance with legal constraints was reached. After different shutdowns in the factory, the period to recover the previous performance of the biotrickling reactor was minimal. A weekend dehydration strategy was developed and implemented to control the pressure drop associated with excessive biomass accumulation.

  4. Cognitive issues in autonomous spacecraft-control operations: An investigation of software-mediated decision making in a scaled environment

    Science.gov (United States)

    Murphy, Elizabeth Drummond

    As advances in technology are applied in complex, semi-automated domains, human controllers are distanced from the controlled process. This physical and psychological distance may both facilitate and degrade human performance. To investigate cognitive issues in spacecraft ground-control operations, the present experimental research was undertaken. The primary issue concerned the ability of operations analysts who do not monitor operations to make timely, accurate decisions when autonomous software calls for human help. Another key issue involved the potential effects of spatial-visualization ability (SVA) in environments that present data in graphical formats. Hypotheses were derived largely from previous findings and predictions in the literature. Undergraduate psychology students were assigned at random to a monitoring condition or an on-call condition in a scaled environment. The experimental task required subjects to decide on the veracity of a problem diagnosis delivered by a software process on-board a simulated spacecraft. To support decision-making, tabular and graphical data displays presented information on system status. A level of software confidence in the problem diagnosis was displayed, and subjects reported their own level of confidence in their decisions. Contrary to expectations, the performance of on-call subjects did not differ significantly from that of continuous monitors. Analysis yielded a significant interaction of sex and condition: Females in the on-call condition had the lowest mean accuracy. Results included a preference for bar charts over line graphs and faster performance with tables than with line graphs. A significant correlation was found between subjective confidence and decision accuracy. SVA was found to be predictive of accuracy but not speed; and SVA was found to be a stronger predictor of performance for males than for females. Low-SVA subjects reported that they relied more on software confidence than did medium- or high

  5. PedsQL gastrointestinal symptoms scales and gastrointestinal worry scales in pediatric patients with inflammatory bowel disease in comparison with healthy controls

    Science.gov (United States)

    Patient-reported outcomes are essential in determining the broad impact of inflammatory bowel disease (IBD) and treatments from the patient's perspective. The primary study objectives were to compare the gastrointestinal symptoms and worry of pediatric patients with IBD with matched healthy controls...

  6. Application of high-throughput mini-bioreactor system for systematic scale-down modeling, process characterization, and control strategy development.

    Science.gov (United States)

    Janakiraman, Vijay; Kwiatkowski, Chris; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2015-01-01

    High-throughput systems and processes have typically been targeted for process development and optimization in the bioprocessing industry. For process characterization, bench scale bioreactors have been the system of choice. Due to the need for performing different process conditions for multiple process parameters, the process characterization studies typically span several months and are considered time and resource intensive. In this study, we have shown the application of a high-throughput mini-bioreactor system viz. the Advanced Microscale Bioreactor (ambr15(TM) ), to perform process characterization in less than a month and develop an input control strategy. As a pre-requisite to process characterization, a scale-down model was first developed in the ambr system (15 mL) using statistical multivariate analysis techniques that showed comparability with both manufacturing scale (15,000 L) and bench scale (5 L). Volumetric sparge rates were matched between ambr and manufacturing scale, and the ambr process matched the pCO2 profiles as well as several other process and product quality parameters. The scale-down model was used to perform the process characterization DoE study and product quality results were generated. Upon comparison with DoE data from the bench scale bioreactors, similar effects of process parameters on process yield and product quality were identified between the two systems. We used the ambr data for setting action limits for the critical controlled parameters (CCPs), which were comparable to those from bench scale bioreactor data. In other words, the current work shows that the ambr15(TM) system is capable of replacing the bench scale bioreactor system for routine process development and process characterization. © 2015 American Institute of Chemical Engineers.

  7. Decentralized control of large-scale systems: Fixed modes, sensitivity and parametric robustness. Ph.D. Thesis - Universite Paul Sabatier, 1985

    Science.gov (United States)

    Tarras, A.

    1987-01-01

    The problem of stabilization/pole placement under structural constraints of large scale linear systems is discussed. The existence of a solution to this problem is expressed in terms of fixed modes. The aim is to provide a bibliographic survey of the available results concerning the fixed modes (characterization, elimination, control structure selection to avoid them, control design in their absence) and to present the author's contribution to this problem which can be summarized by the use of the mode sensitivity concept to detect or to avoid them, the use of vibrational control to stabilize them, and the addition of parametric robustness considerations to design an optimal decentralized robust control.

  8. Role Preferences of People with Multiple Sclerosis: Image-Revised, Computerized Self-Administered Version of the Control Preference Scale.

    Directory of Open Access Journals (Sweden)

    Alessandra Solari

    Full Text Available The Control Preference Scale (CPS is the most frequently used measure of patients' preferred roles in treatment decisions. We revised the original CPS and developed a new computerized patient self-administered version (eCPS. We used the eCPS to assess role preferences, and their determinants, in Italian and German people with multiple sclerosis (MS.New cartoons were produced, based on MS health professional and patient input/feedback and previous findings, and pilot tested on 26 Italian and German MS patients. eCPS acceptability and reliability (weighted kappa statistic, wK in comparison to the original tool, was determined in 92 MS patients who received both CPS versions in random order.The new cartoons were well accepted and easily interpreted by patients, who reported they based their choices mainly on the text and considered the images of secondary importance. eCPS reliability was moderate (wK 0.53, 95% confidence interval [CI] 0.40-0.65 and similar to the test-retest reliability of face-to-face administration assessed in a previous publication (wK 0.65, 95% CI 0.45-0.81. Higher education (odds ratio [OR] 3.74, 95% CI 1.00-14.05 and German nationality (OR 10.30, 95% CI 3.10-34.15 were associated with preference for an active role in the logistic model.The newly devised eCPS was well received and considered easy to use by MS patients. Reliability was in line with that of the original version. Role preference appears affected by cultural characteristics and (borderline statistical significance education.

  9. Traditional Cantonese diet and nasopharyngeal carcinoma risk: a large-scale case-control study in Guangdong, China

    Directory of Open Access Journals (Sweden)

    Jia Wei-Hua

    2010-08-01

    Full Text Available Abstract Background Nasopharyngeal carcinoma (NPC is rare in most parts of the world but is a common malignancy in southern China, especially in Guangdong. Dietary habit is regarded as an important modifier of NPC risk in several endemic areas and may partially explain the geographic distribution of NPC incidence. In China, rapid economic development during the past few decades has changed the predominant lifestyle and dietary habits of the Chinese considerably, requiring a reassessment of diet and its potential influence on NPC risk in this NPC-endemic area. Methods To evaluate the association between dietary factors and NPC risk in Guangdong, China, a large-scale, hospital-based case-control study was conducted. 1387 eligible cases and 1459 frequency matched controls were recruited. Odds ratios (ORs and the corresponding 95% confidence intervals (CIs were estimated using a logistic regression model, adjusting for age, sex, education, dialect, and habitation household type. Results Observations made include the following: 1 consumption of canton-style salted fish, preserved vegetables and preserved/cured meat were significantly associated with increased risk of NPC, with enhanced odds ratios (OR of 2.45 (95% CI: 2.03-2.94, 3.17(95% CI: 2.68-3.77 and 2.09 (95% CI: 1.22-3.60 respectively in the highest intake frequency stratum during childhood; 2 consumption of fresh fruit was associated with reduced risk with a dose-dependent relationship (p = 0.001; and 3 consumption of Canton-style herbal tea and herbal slow-cooked soup was associated with decreased risk, with ORs of 0.84 (95% CI: 0.68-1.03 and 0.58 (95% CI: 0.47-0.72 respectively in the highest intake frequency stratum. In multivariate analyses, these associations remained significant. Conclusions It can be inferred that previously established dietary risk factors in the Cantonese population are still stable and have contributed to the incidence of NPC.

  10. Reductions in malaria and anaemia case and death burden at hospitals following scale-up of malaria control in Zanzibar, 1999-2008

    NARCIS (Netherlands)

    M.W. Aregawi (Maru); A.S. Ali (Abdullah); A.-W. Al-Mafazy; F. Molteni (Fabrizio); S. Katikiti (Samson); M. Warsame (Marian); R.J. Njau; R. Komatsu (Ryuichi); E.L. Korenromp (Eline); M. Hosseini (Mehran); D. Low-Beer (Daniel); A. Bjorkman (Anders); U. D'Alessandro (Umberto); M. Coosemans (Marc); M. Otten (Mac)

    2011-01-01

    textabstractBackground: In Zanzibar, the Ministry of Health and partners accelerated malaria control from September 2003 onwards. The impact of the scale-up of insecticide-treated nets (ITN), indoor-residual spraying (IRS) and artemisinin-combination therapy (ACT) combined on malaria burden was

  11. A SIMPLE METHOD TO CONTROL THE MOISTURE CONTENT OF THE FERMENTING MEDIUM DURING LABORATORY-SCALE SOLID-STATE FERMENTATION EXPERIMENTS

    OpenAIRE

    Borzani, W.; SALOMÃO,G. L.; Martins, J.C.; Alonso, V.

    1999-01-01

    When the moisture content of the fermenting medium significantly decreases during laboratory-scale solid-state fermentation tests, the quantity of water to be periodically added to the medium in order to control its moisture content may be evaluated from the water evaporation rate of the non-inoculated medium.

  12. A SIMPLE METHOD TO CONTROL THE MOISTURE CONTENT OF THE FERMENTING MEDIUM DURING LABORATORY-SCALE SOLID-STATE FERMENTATION EXPERIMENTS

    Directory of Open Access Journals (Sweden)

    W. BORZANI

    1999-03-01

    Full Text Available When the moisture content of the fermenting medium significantly decreases during laboratory-scale solid-state fermentation tests, the quantity of water to be periodically added to the medium in order to control its moisture content may be evaluated from the water evaporation rate of the non-inoculated medium.

  13. Volumetric water control in a large-scale open canal irrigation system with many smallholders: The case of Chancay-Lambayeque in Peru

    NARCIS (Netherlands)

    Vos, J.M.C.; Vincent, L.F.

    2011-01-01

    Volumetric water control (VWC) is widely seen as a means to increase productivity through flexible scheduling and user incentives to apply just enough water. However, the technical and social requirements for VWC are poorly understood. Also, many experts assert that VWC in large-scale open canals

  14. A scaled experimental study of control blade insertion dynamics in Pebble-Bed Fluoride-Salt-Cooled High-Temperature Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Buster, Grant C., E-mail: grant.buster@gmail.com; Laufer, Michael R.; Peterson, Per F.

    2016-07-15

    Highlights: • A granular dynamics scaling methodology is discussed. • Control blade insertion in a representative pebble-bed core is experimentally studied. • Control blade insertion forces and pebble displacements are experimentally measured. • X-ray tomography techniques are used to observe pebble displacement distributions. - Abstract: Direct control element insertion into a pebble-bed reactor core is proposed as a viable control system in molten-salt-cooled pebble-bed reactors. Unlike helium-cooled pebble-bed reactors, this reactor type uses spherical fuel elements with near-neutral buoyancy in the molten-salt coolant, thus reducing contact forces on the fuel elements. This study uses the X-ray Pebble Bed Recirculation Experiment facility to measure the force required to insert a control element directly into a scaled pebble-bed. The required control element insertion force, and therefore the contact force on fuel elements, is measured to be well below recommended limits. Additionally, X-ray tomography is used to observe how the direct insertion of a control element physically displaces spherical fuel elements. The tomography results further support the viability of direct control element insertion into molten-salt-cooled pebble-bed reactor cores.

  15. Effectiveness of a controlled release chlorhexidine chip (PerioColTM‑CG as an adjunctive to scaling and root planing when compared to scaling and root planing alone in the treatment of chronic periodontitis: A comparative study

    Directory of Open Access Journals (Sweden)

    Kameswari Kondreddy

    2012-01-01

    Full Text Available Aims and objectives: The aim of this study is to evaluate the effectiveness of a controlled-release chlorhexidine chip as an adjunctive therapy to scaling and root planing when compared with scaling and root planing alone in the treatment of chronic periodontitis. Materials and Methods: 20 patients with a total number of 40 posterior sites were selected. These sites were divided into two groups in a split mouth design,: Group A (control site had 20 sites treated with scaling and root planing alone and Group B (test site had 20 sites treated with scaling and root planing and PerioCol TM -CG. The clinical parameters (Plaque index, bleeding on probing, probing pocket depth, clinical attachment level were recorded at baseline, 90 th and 180 th day for both the groups. Results: When both groups were compared the change in Plaque index was significantly higher in Group B when compared to Group A on the 90 th day and 180 th day. However, there was no statistically significant difference in the mean percentage of gingival bleeding sites between the two groups on the 90 th day, though Group B showed a statistically higher reduction in the mean percentage of gingival bleeding sites at the end of 180 th day. There was no statistically significant difference in probing pocket depth between the two groups on both 90 th and 180 th day. Gain in clinical attachment level was significantly higher in Group B when compared to Group A on the 90 th and 180 th day. Conclusion: From the results observed in this study, it can be concluded that the adjunctive use of PerioCol TM -CG was safe and provided significant improvement in both Plaque index and gingival bleeding index. It was also more favorable than scaling and root planing alone for gain in clinical attachment level.

  16. Multi‐scale topographic control of southwest vortex formation in Tibetan Plateau region in an idealized simulation

    National Research Council Canada - National Science Library

    Wang, Qi‐Wei; Tan, Zhe‐Min

    2014-01-01

    The southwest vortex (SWV) is a lee vortex occurring on the leeside of the Tibetan Plateau in southwestern China, which is strongly affected by the different scale topography of the Tibetan Plateau, Hengduan Cordillera, and Sichuan Basin...

  17. From Ecosystem-Scale to Litter Biochemistry: Controls on Carbon Sequestration in Coastal Wetlands of the Western Gulf of Mexico

    Science.gov (United States)

    Louchouarn, P.; Kaiser, K.; Norwood, M. J.; Sterne, A. M. E.; Armitage, A. R.; HighField, W.; Brody, S.

    2015-12-01

    Landscape-level shifts in plant species distribution and abundance can fundamentally change the structure and services of an ecosystem. Such shifts are occurring within mangrove-marsh ecotones of the U.S., where over the last few decades, relatively mild winters have led to mangrove expansion into areas previously occupied by salt marsh plants. Here we present the synthesis of 3 years of multidisciplinary work to quantify ecosystem shifts at the regional scale, along the entire Texas (USA) coast of the western Gulf of Mexico, and transcribe these shifts into carbon (C) sequestration mass balances. We classified Landsat-5 Thematic Mapper images using artificial neural networks to quantify shifts in areal coverage of black mangrove (Avicennia germinans) and salt marsh (Spartina alterniflora and other grass and forb species) over 20 years across the Texas Gulf coast. Between 1990 and 2010, mangrove area expanded by 74% (+16 km2). Concurrently, salt marsh area experienced a net loss of 24% (-78 km2). Most of that loss was due to conversion to tidal flats or water, likely a result of relative sea level rise, with only 6% attributable to mangrove expansion. Although relative carbon load (per surface area) are statistically larger for mangrove wetlands, total C loads are larger for salt marsh wetlands due to their greater aerial coverage. The entire loss of above ground C (~7.0·109 g), was offset by salt marsh expansion (2.0·109 g) and mangrove expansion (5.6·109 g) over the study period. Concurrently, the net loss in salt marsh coverage led to a loss in below ground C accumulation capacity of 2.0·109 g/yr, whereas the net expansion of mangrove wetlands led to an added below ground C accumulation capacity of 0.4·109 g/yr. Biomarker data show that neutral carbohydrates and lignin contributed 30-70% and 10-40% of total C, respectively, in plant litter and surface sediments. Sharp declines of carbohydrate yields with depth occur parallel to increases in lignin

  18. Seasonal controls on snow distribution and aerial ablation at the snow-patch and landscape scales, McMurdo Dry Valleys, Antarctica

    Directory of Open Access Journals (Sweden)

    J. W. Eveland

    2013-06-01

    Full Text Available Accumulated snow in the McMurdo Dry Valleys, while limited, has great ecological significance to subnivian soil environments. Though sublimation dominates the ablation process in this region, measurable increases in soil moisture and insulation from temperature extremes provide more favorable conditions with respect to subnivian soil communities. While precipitation is not substantial, significant amounts of snow can accumulate, via wind transport, in topographic lees along the valley bottoms, forming thousands of discontinuous snow patches. These patches have the potential to act as significant sources of local meltwater, controlling biogeochemical cycling and the landscape distribution of microbial communities. Therefore, determining the spatial and temporal dynamics of snow at multiple scales is imperative to understanding the broader ecological role of snow in this region. High-resolution satellite imagery acquired during the 2009–2010 and 2010–2011 austral summers was used to quantify the distribution of snow across Taylor and Wright valleys. Extracted snow-covered area from the imagery was used as the basis for assessing inter-annual variability and seasonal controls on accumulation and ablation of snow at multiple scales. In addition to landscape analyses, fifteen 1 km2 plots (3 in each of 5 study regions were selected to assess the prevalence of snow cover at finer spatial scales, referred to herein as the snow-patch scale. Results confirm that snow patches tend to form in the same locations each year with some minor deviations observed. At the snow-patch scale, neighboring patches often exhibit considerable differences in aerial ablation rates, and particular snow patches do not reflect trends for snow-covered area observed at the landscape scale. These differences are presumably related to microtopographic influences acting on individual snow patches, such as wind sheltering and differences in snow depth due to the underlying

  19. Industrial-scale production and purification of a heterologous protein in Lactococcus lactis using the nisin-controlled gene expression system NICE: The case of lysostaphin

    Directory of Open Access Journals (Sweden)

    Floris Esther

    2005-05-01

    Full Text Available Abstract Background The NIsin-Controlled gene Expression system NICE of Lactococcus lactis is one of the most widespread used expression systems of Gram-positive bacteria. It is used in more than 100 laboratories for laboratory-scale gene expression experiments. However, L. lactis is also a micro-organism with a large biotechnological potential. Therefore, the aim of this study was to test whether protein production in L. lactis using the NICE system can also effectively be performed at the industrial-scale of fermentation. Results Lysostaphin, an antibacterial protein (mainly against Staphylococcus aureus from S. simulans biovar. Staphylolyticus, was used as a model system. Food-grade lysostaphin expression constructs in L. lactis were grown at 1L-, 300-L and 3000-L scale and induced with nisin for lysostaphin production. The induction process was equally effective at all scales and yields of about 100 mg/L were obtained. Up-scaling was easy and required no specific effort. Furthermore, we describe a simple and effective way of downstream processing to obtain a highly purified lysostaphin, which has been used for clinical phase I trials. Conclusion This is the first example that shows that nisin-regulated gene expression in L. lactis can be used at industrial scale to produce large amounts of a target protein, such as lysostaphin. Downstream processing was simple and in a few steps produced a highly purified and active enzyme.

  20. Field Testing of a Wet FGD Additive for Enhanced Mercury Control - Task 3 Full-scale Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Gary Blythe

    2007-05-01

    This Topical Report summarizes progress on Cooperative Agreement DE-FC26-04NT42309, 'Field Testing of a Wet FGD Additive'. The objective of the project is to demonstrate the use of a flue gas desulfurization (FGD) additive, Degussa Corporation's TMT-15, to prevent the reemission of elemental mercury (Hg{sup 0}) in flue gas exiting wet FGD systems on coal-fired boilers. Furthermore, the project intends to demonstrate whether the additive can be used to precipitate most of the mercury (Hg) removed in the wet FGD system as a fine TMT salt that can be separated from the FGD liquor and bulk solid byproducts for separate disposal. The project is conducting pilot- and full-scale tests of the TMT-15 additive in wet FGD absorbers. The tests are intended to determine required additive dosages to prevent Hg{sup 0} reemissions and to separate mercury from the normal FGD byproducts for three coal types: Texas lignite/Power River Basin (PRB) coal blend, high-sulfur Eastern bituminous coal, and low-sulfur Eastern bituminous coal. The project team consists of URS Group, Inc., EPRI, TXU Generation Company LP, Southern Company, and Degussa Corporation. TXU Generation has provided the Texas lignite/PRB cofired test site for pilot FGD tests, Monticello Steam Electric Station Unit 3. Southern Company is providing the low-sulfur Eastern bituminous coal host site for wet scrubbing tests, as well as the pilot- and full-scale jet bubbling reactor (JBR) FGD systems to be tested. IPL, an AES company, provided the high-sulfur Eastern bituminous coal full-scale FGD test site and cost sharing. Degussa Corporation is providing the TMT-15 additive and technical support to the test program as cost sharing. The project is being conducted in six tasks. Of the six project tasks, Task 1 involves project planning and Task 6 involves management and reporting. The other four tasks involve field testing on FGD systems, either at pilot or full scale. The four tasks include: Task 2 - Pilot

  1. On the validity of self-report assessment of cognitive abilities: Attentional control scale associations with cognitive performance, emotional adjustment, and personality.

    Science.gov (United States)

    Williams, Paula G; Rau, Holly K; Suchy, Yana; Thorgusen, Sommer R; Smith, Timothy W

    2017-05-01

    Individual differences in attentional control involve the ability to voluntarily direct, shift, and sustain attention. In studies of the role of attentional control in emotional adjustment, social relationships, and vulnerability to the effects of stress, self-report questionnaires are commonly used to measure this construct. Yet, convincing evidence of the association between self-report scales and actual cognitive performance has not been demonstrated. Across 2 independent samples, we examined associations between self-reported attentional control (Attentional Control Scale; ACS), self-reported emotional adjustment, Five-Factor Model personality traits (NEO Personality Inventory-Revised) and performance measures of attentional control. Study 1 examined behavioral performance on the Attention Network Test (ANT; Fan, McCandliss, Sommer, Raz, & Posner, 2002) and the Modified Switching Task (MST; Suchy & Kosson, 2006) in a large sample (n = 315) of healthy young adults. Study 2 (n = 78) examined behavioral performance on standardized neuropsychological tests of attention, including Conner's Continuous Performance Test-II and subtests from the Wechsler Adult Intelligence Scales, Third Edition (WAIS-III; Psychological Corporation, 1997) and Delis-Kaplan Executive Function System (D-KEFS; Delis, Kaplan, & Kramer, 2001). Results indicated that the ACS was largely unrelated to behavioral performance measures of attentional control but was significantly associated with emotional adjustment, neuroticism, and conscientiousness. These findings suggest that although self-reported attentional control may be a useful construct, researchers using the ACS should exercise caution in interpreting it as a proxy for actual cognitive ability or performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. CARBO-CONTROLE. Quantification of the carbon flux and stocks at the european and national scale; CARBO-CONTROLE. Quantification des flux et stocks de carbone au niveau Europeen et national

    Energy Technology Data Exchange (ETDEWEB)

    Ciais, P

    2007-07-01

    The CARBO-CONTROLE project aims to evaluate the different methodologies to estimate the CO{sub 2} flux at the european, national and regional scale. The strategy is to combine a crumbling, down scaling, of the flux at a big scale, by inverting the atmospheric CO{sub 2} measures with a aggregation, up scaling, of the national stocks and flux from the climatic parameters of a model of ecosystems.They show that with the monthly data of the global network of CO{sub 2} monitoring stations, it is possible to obtain an estimation of the european flux. Meanwhile the errors bond to the leak of continental stations are of the order of the flux average. (A.L.B.)

  3. Improving detection and identification of seismic signals due to landslides: a methodology based on field scale controlled experiments

    Science.gov (United States)

    Yfantis, G.; Carvajal, H. E.; Pytharouli, S.; Lunn, R. J.

    2013-12-01

    A number of published studies use seismic sensors to understand the physics involved in slope deformation. In this research we artificially induce failure to two meter scaled slopes in the field and use 12 short period 3D seismometers to monitor the failure. To our knowledge there has been no previous controlled experiments that can allow calibration and validation of the interpreted seismic signals. Inside the body of one of the artificial landslides we embed a pile of glass shards. During movement the pile deforms emitting seismic signals due to friction among the glass shards. Our aim is twofold: First we investigate whether the seismic sensors can record pre-cursory and failure signals. Secondly, we test our hypothesis that the glass shards produce seismic signals with higher amplitudes and a distinct frequency pattern, compared to those emitted by common landslide seismicity and local background noise. Two vertical faces, 2m high, were excavated 3m apart in high porous tropical clay. This highly attenuating material makes the detection of weak seismic signals challenging. Slope failure was induced by increasing the vertical load at the landslide's crown. Special care was taken in the design of all experimental procedures to not add to the area's seismic noise. Measurements took place during 18 hours (during afternoon and night) without any change in soil and weather conditions. The 3D sensors were placed on the ground surface close to the crown, forming a dense microseismic network with 5-to-10m spacing and two nanoseismic arrays, with aperture sizes of 10 and 20 m. This design allowed a direct comparison of the recorded signals emitted by the two landslides. The two faces failed for loading between 70 and 100kN and as a result the pile of glass shards was horizontally deformed allowing differential movement between the shards. After the main failure both landslides were continuing to deform due to soil compaction and horizontal displacement. We apply signal

  4. From transport and storage to control of the process: the challenge of biodigestion from drawings of swine in agroindustrial scale

    Directory of Open Access Journals (Sweden)

    José Carlos Souza Oliveira

    2017-07-01

    The objective of this article is to analyze some factors that represent challenges to the application of biodigestion process for energy generation from swine waste on an agroindustrial scale, thus contributing to important reflection on the design and installation of biodigesters in agroindustrial activities.

  5. Smart dynamic rotor control using active flaps on a small-scale wind turbine: aeroelastic modeling and comparison with wind tunnel measurements

    DEFF Research Database (Denmark)

    Barlas, Thanasis K.; van Wingerden, W.; Hulskamp, A.W.

    2013-01-01

    In this paper, the proof of concept of a smart rotor is illustrated by aeroelastic simulations on a small-scale rotor and comparison with wind tunnel experiments. The application of advanced feedback controllers using actively deformed flaps in the wind tunnel measurements is shown to alleviate...... dynamic loads leading to considerable fatigue load reduction. The numerical method for aeroelastically simulating such an experiment is described, together with the process of verifying the methods for accurate prediction of the load reduction potential of such concepts. The small-scale rotor is simulated...... using the aeroelastic tool, load predictions are compared with the wind tunnel measurements, and similar control concepts are compared and evaluated in the numerical environment. Conclusions regarding evaluation of the performance of smart rotor concepts for wind turbines are drawn from this threefold...

  6. Application of in-plant control measures in some Egyptian micro-scale dairy enterprises and its impact on heavy metal contents of their products.

    Science.gov (United States)

    Abd El-Salam, Magda Magdy; Farahat, Mohamed F; Abu-Zuid, Gaber I; Saad, Samia G

    2017-09-05

    Egypt is encouraging micro-scale enterprises as proved to be one of the most important reasons of economic growth. Most of the annual milk production is processed in micro-scale dairy enterprises located in squatter areas with high health risks and negative environmental impact. The aim of this study was to assess the effectiveness of in-plant control measures in controlling lead and cadmium levels in dairy products from nine Egyptian micro-scale enterprises. The results revealed that white cheese enterprises had the highest mean lead and cadmium contents; both in their raw milk (0.712 and 0.134 mg/L, respectively) and final products (0.419 and 0.061 mg/kg). Higher compliance percentages were found with cadmium levels specified in the Egyptian standards than with lead levels and ranged from 59.4% in raw milk to 100% in dry milk for cadmium levels and from 8.3% in white cheese to 66.7% in ice cream for lead; moreover, none of the collected raw milk samples were complying with the lead levels. After implementation of in-plant control measures, lower lead levels were found in all samples with reduction percentages ranging from 35.2% in raw milk from the ice cream enterprises to 73.2% in yoghurt; moreover, higher percentages of samples complied with cadmium levels. This study highlights the urgent need for applying in-plant control measures to the Egyptian micro-scale dairy enterprises to improve both safety and quality of their products.

  7. Personality traits in established schizophrenia: aspects of usability and differences between patients and controls using the Swedish universities Scales of Personality

    OpenAIRE

    Fagerberg, Tomas; S?derman, Erik; Gustavsson, J. Petter; Agartz, Ingrid; J?nsson, Erik G

    2016-01-01

    Abstract Background: Personality is considered as an important aspect that can affect symptoms and social function in persons with schizophrenia. The personality questionnaire Swedish universities Scales of Personality (SSP) has not previously been used in psychotic disorder. Aims: To investigate if SSP has a similar internal consistency and factor structure in a psychosis population as among healthy controls and if patients with psychotic disorders differ from non-psychotic individuals in th...

  8. Field Testing of a Wet FGD Additive for Enhanced Mercury Control - Task 5 Full-Scale Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Gary Blythe; MariJon Owens

    2007-12-01

    This Topical Report summarizes progress on Cooperative Agreement DE-FC26-04NT42309, 'Field Testing of a Wet FGD Additive'. The objective of the project is to demonstrate the use of two flue gas desulfurization (FGD) additives, Evonik Degussa Corporation's TMT-15 and Nalco Company's Nalco 8034, to prevent the re-emission of elemental mercury (Hg{sup 0}) in flue gas exiting wet FGD systems on coal-fired boilers. Furthermore, the project intends to demonstrate whether the additive can be used to precipitate most of the mercury (Hg) removed in the wet FGD system as a fine salt that can be separated from the FGD liquor and bulk solid byproducts for separate disposal. The project is conducting pilot- and full-scale tests of the additives in wet FGD absorbers. The tests are intended to determine required additive dosages to prevent Hg{sup 0} re-emissions and to separate mercury from the normal FGD byproducts for three coal types: Texas lignite/Powder River Basin (PRB) coal blend, high-sulfur Eastern bituminous coal, and low-sulfur Eastern bituminous coal. The project team consists of URS Group, Inc., EPRI, Luminant Power (was TXU Generation Company LP), Southern Company, IPL (an AES company), Evonik Degussa Corporation and the Nalco Company. Luminant Power has provided the Texas lignite/PRB co-fired test site for pilot FGD tests and cost sharing. Southern Company has provided the low-sulfur Eastern bituminous coal host site for wet scrubbing tests, as well as the pilot- and full-scale jet bubbling reactor (JBR) FGD systems tested. IPL provided the high-sulfur Eastern bituminous coal full-scale FGD test site and cost sharing. Evonik Degussa Corporation is providing the TMT-15 additive, and the Nalco Company is providing the Nalco 8034 additive. Both companies are also supplying technical support to the test program as in-kind cost sharing. The project is being conducted in six tasks. Of the six project tasks, Task 1 involves project planning and Task 6

  9. Framework for Evaluating the Health Impact of the Scale-Up of Malaria Control Interventions on All-Cause Child Mortality in Sub-Saharan Africa.

    Science.gov (United States)

    Yé, Yazoume; Eisele, Thomas P; Eckert, Erin; Korenromp, Eline; Shah, Jui A; Hershey, Christine L; Ivanovich, Elizabeth; Newby, Holly; Carvajal-Velez, Liliana; Lynch, Michael; Komatsu, Ryuichi; Cibulskis, Richard E; Moore, Zhuzhi; Bhattarai, Achuyt

    2017-09-01

    Concerted efforts from national and international partners have scaled up malaria control interventions, including insecticide-treated nets, indoor residual spraying, diagnostics, prompt and effective treatment of malaria cases, and intermittent preventive treatment during pregnancy in sub-Saharan Africa (SSA). This scale-up warrants an assessment of its health impact to guide future efforts and investments; however, measuring malaria-specific mortality and the overall impact of malaria control interventions remains challenging. In 2007, Roll Back Malaria's Monitoring and Evaluation Reference Group proposed a theoretical framework for evaluating the impact of full-coverage malaria control interventions on morbidity and mortality in high-burden SSA countries. Recently, several evaluations have contributed new ideas and lessons to strengthen this plausibility design. This paper harnesses that new evaluation experience to expand the framework, with additional features, such as stratification, to examine subgroups most likely to experience improvement if control programs are working; the use of a national platform framework; and analysis of complete birth histories from national household surveys. The refined framework has shown that, despite persisting data challenges, combining multiple sources of data, considering potential contributions from both fundamental and proximate contextual factors, and conducting subnational analyses allows identification of the plausible contributions of malaria control interventions on malaria morbidity and mortality.

  10. Postharvest control of western flower thrips (Thysanoptera: Thripidae) and California red scale (Hemiptera: Diaspididae) with ethyl formate and its impact on citrus fruit quality.

    Science.gov (United States)

    Pupin, Francine; Bikoba, Veronique; Biasi, William B; Pedroso, Gabriel M; Ouyang, Yuling; Grafton-Cardwell, Elizabeth E; Mitcham, Elizabeth J

    2013-12-01

    The postharvest control of arthropod pests is a challenge that the California citrus industry must overcome when exporting fruit overseas. Currently, methyl bromide fumigation is used to control postharvest pests on exported citrus, but it may soon be unavailable because of use restrictions and cost of this health-hazard ozone-depleting chemical. Ethyl formate is a natural plant volatile and possible alternative to methyl bromide in postharvest insect control. The objectives of this study were 1) to evaluate the mortality of third instar California red scale [Aonidiella aurantii (Maskell)] (Hemiptera: Diaspididae) and adult western flower thrips [Frankliniella occidentalis (Pergande)] (Thysanoptera: Thripidae) under a wide range of ethyl formate concentrations, 2) to determine the ethyl formate concentration required to reach a Probit 9 level of control for both pests, and 3) to test the effects of ethyl formate fumigation on the quality of navel oranges [Citrus sinensis (L.) Osbeck] and lemons [Citrus limon (L.) Burman f.] at 24 h after fumigation, and at different time periods to simulate shipping plus storage (5 wk at 5 degrees C), and shipping, storage, handling, and shelf-life (5 wk at 5 degrees C, plus 5 d at 15 degrees C, and 2 d at 20 degrees C). The results indicate that ethyl formate is a promising alternative to methyl bromide for the California citrus industry, because of successful control of adult western flower thips and third instar California red scale and no deleterious effect on fruit quality at any of the evaluated periods and quality parameters.

  11. The Ability of Recovery Locus of Control Scale (RLOC) and Post-traumatic Stress Symptoms (PTSS) to Predict the Physical Functioning of Stroke Patients.

    Science.gov (United States)

    Mohd Zulkifly, Mohd Faizal; Ghazali, Shazli Ezzat; Che Din, Normah; Desa, Asmawati; Raymond, Azman Ali

    2015-09-01

    The aim of this study was to address the ability of the recovery locus of control scale (RLOC) and post-traumatic stress symptoms (PTSS) to predict physical functioning among stroke patients. In addition, the best predictors within the subdomains of the RLOC and PTSS were also investigated. A total of 147 stroke patients aged 33-85 years who had intact cognitive functioning were involved in the study. The Recovery Locus of Control Scale (RLOC), the Impact of Event Scale-Revised (IES-R), and the Barthel Index (ADL) were administered to respondents six weeks after stroke. The results showed that the RLOC and PTSS were significant predictors and were capable of predicting 31% of the physical functioning of stroke patients (adjusted R2 = 0.31; P < 0.001). Furthermore, with respect to clinical factors, the affected lesion side contributed to predicting 7% of the physical functioning (R2= 0.07; P < 0.001). A hierarchical regression analysis found that the internal recovery locus of control (IRLOC) was a predictor capable of explaining 18% of the predicted physical functioning (adjusted R2= 0.18; P < 0.001). Meanwhile, avoidance was the most influential significant predictor among PTSS, contributing to 24% of the predicting physical functioning (adjusted R2= 0.24; P < 0.001). In conclusion, the RLOC and PTSS were capable of predicting physical functioning among stroke patients.

  12. Large-Scale Control of the Probability Distribution Function of Precipitation over the Continental US in Observations and Models, in the Current and Future Climat

    Science.gov (United States)

    Straus, D. M.

    2016-12-01

    The goals of this research are to: (a) identify features of the probability distribution function (pdf) of pentad precipitation over the continental US (CONUS) that are controlled by the configuration of the large-scale fields, including both tails of the pdf, hence droughts and floods, and the overall shape of the pdf, e.g. skewness and kurtosis; (b) estimate the changes in the properties of the pdf controlled by the large-scale in a future climate. We first describe the significant dependence of the observed precipitation pdf conditioned on circulation regimes over CONUS. The regime states, and the number of regimes, are obtained by a method that assures a high degree of significance, and a high degree of pattern correlation between the states in a regime and its average. The regime-conditioned pdfs yield information on times scales from intra-seasonal to inter-annual. We then apply this method to atmospheric simulations run with the EC-Earth version 3 model for historical sea-surface temperatures (SST) and future (RCP8.5 CMIP5 scenario) estimates of SST, at resolutions T255 and T799, to understand what dynamically controlled changes in the precipitation pdf can be expected in a future climate.

  13. A theoretical bilevel control scheme for power networks with large-scale penetration of distributed renewable resources

    DEFF Research Database (Denmark)

    Boroojeni, Kianoosh; Amini, M. Hadi; Nejadpak, Arash

    2016-01-01

    the residential demand and DRRs, we use the Gaussian white noise added to some periodic signals, formulated as a stochastic process. In the second level of the proposed control framework, we take the advantage of bulk generation units to improve the reliability by a global flow controller. In other words, we get...

  14. A Randomized Controlled Trial of an At-Scale Language and Literacy Intervention in Childcares in Denmark

    DEFF Research Database (Denmark)

    Højen, Anders; Bleses, Dorthe; Dale, Philip

    on efficacy rather than “real-life” effectiveness at scale. We evaluated a systematic and explicit language-literacy intervention (“SPELL”) at scale, including all children in the participating childcares in Denmark, a country with little focus on school-readiness-related skills. The intervention consisted...... of 40 high-quality book-reading lessons with an explicit scope and sequence of language and literacy instruction targeting phonological awareness, print awareness, vocabulary and narrative development. Childcare educators delivered 40 30-minute biweekly lessons. We examined the effect...... of the intervention in three arms: SPELL-basic, SPELL with supplementary home intervention, and SPELL with professional development of educators. Pre- and posttest scores were obtained using a standardized language and literacy test. Hierarchical linear modeling of change scores was the primary analysis. 142...

  15. An effective and simplified scale-up strategy for acarbose fermentation based on the carbon source control.

    Science.gov (United States)

    Li, Kun-tai; Wie, Sai-jin; Huang, Lin; Cheng, Xin

    2012-02-01

    The scale-up strategy for acarbose fermentation by Actinoplanes sp. A56 was explored in this paper. The results obtained in shake-flask cultivation demonstrated that the ratio of maltose and glucose had significant effects on the biosynthesis of acarbose, and the feeding medium containing 3:1 (mass ratio) of maltose and glucose was favorable for acarbose production. Then the correlation of the carbon source concentration with acarbose production was further investigated in 100-l fermenter, and the results showed that 7.5-8.0 g of total sugar/100 ml and 4.0-4.5 g of reducing sugar/100 ml were optimal for acarbose production. Based on the results in 100-l fermenter, an effective and simplified scale-up strategy was successfully established for acarbose fermentation in a 30-m(3) fermenter, by using total sugar and reducing sugar as the scale-up parameter. As a result, 4,327 mg of acarbose/l was obtained at 168 h of fermentation.

  16. Genomic Footprints of Selective Sweeps from Metabolic Resistance to Pyrethroids in African Malaria Vectors Are Driven by Scale up of Insecticide-Based Vector Control.

    Science.gov (United States)

    Barnes, Kayla G; Weedall, Gareth D; Ndula, Miranda; Irving, Helen; Mzihalowa, Themba; Hemingway, Janet; Wondji, Charles S

    2017-02-01

    Insecticide resistance in mosquito populations threatens recent successes in malaria prevention. Elucidating patterns of genetic structure in malaria vectors to predict the speed and direction of the spread of resistance is essential to get ahead of the 'resistance curve' and to avert a public health catastrophe. Here, applying a combination of microsatellite analysis, whole genome sequencing and targeted sequencing of a resistance locus, we elucidated the continent-wide population structure of a major African malaria vector, Anopheles funestus. We identified a major selective sweep in a genomic region controlling cytochrome P450-based metabolic resistance conferring high resistance to pyrethroids. This selective sweep occurred since 2002, likely as a direct consequence of scaled up vector control as revealed by whole genome and fine-scale sequencing of pre- and post-intervention populations. Fine-scaled analysis of the pyrethroid resistance locus revealed that a resistance-associated allele of the cytochrome P450 monooxygenase CYP6P9a has swept through southern Africa to near fixation, in contrast to high polymorphism levels before interventions, conferring high levels of pyrethroid resistance linked to control failure. Population structure analysis revealed a barrier to gene flow between southern Africa and other areas, which may prevent or slow the spread of the southern mechanism of pyrethroid resistance to other regions. By identifying a genetic signature of pyrethroid-based interventions, we have demonstrated the intense selective pressure that control interventions exert on mosquito populations. If this level of selection and spread of resistance continues unabated, our ability to control malaria with current interventions will be compromised.

  17. Minnesota multiphasic personality inventory-2 restructured form (MMPI-2-RF) scale score differences in bariatric surgery candidates diagnosed with binge eating disorder versus BMI-matched controls.

    Science.gov (United States)

    Marek, Ryan J; Ben-Porath, Yossef S; Ashton, Kathleen; Heinberg, Leslie J

    2014-04-01

    Binge Eating Disorder (BED) is among the most common psychiatric disorders in bariatric surgery candidates. The Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) is a broadband, psychological test that includes measures of emotional and behavioral dysfunction, which have been associated with BED behaviors in bariatric surgery candidates; however these studies have lacked appropriate controls. In the current study, we compared MMPI-2-RF scale scores of bariatric surgery patients diagnosed with BED (BED+) with BMI-matched controls without BED (BED-). Three-hundred and seven BED+ participants (72.64% female and 67.87% Caucasian; mean BMI of 51.36 kg/m(2) [SD = 11.94]) were drawn from a large, database (N = 1304). Three-hundred and seven BED- participants were matched on BMI and demographics (72.64% female, 68.63% Caucasian, and mean BMI of 51.30 kg/m(2) [SD = 11.70]). The BED+ group scored significantly higher on measures of Demoralization, Low Positive Emotions, and Dysfunctional Negative Emotions and scored lower on measures of Antisocial Behaviors, reflecting behavioral constraint. Optimal T-Score cutoffs were below the traditional 65 T score for several MMPI-2-RF scales. MMPI-2-RF externalizing measures also added incrementally to differentiating between the groups beyond the Binge Eating Scale (BES). BED+ individuals produced greater elevations on a number of MMPI-2-RF internalizing scales and externalizing scales. Use of the test in conjunction with a clinical interview and other self-report data can further aid the clinician in guiding patients to appropriate treatment to optimize outcome. Copyright © 2013 Wiley Periodicals, Inc.

  18. Application of Genetic Control with Adaptive Scaling Scheme to Signal Acquisition in Global Navigation Satellite System Receiver

    Directory of Open Access Journals (Sweden)

    Ho-Nien Shou

    2012-02-01

    Full Text Available This paper presents a genetic-based control scheme that not only utilizes evolutionary characteristics to find the signal acquisition parameters, but also employs an adaptive scheme to control the search space and avoid the genetic control converging to local optimal value so as to acquire the desired signal precisely and rapidly. Simulations and experiment results show that the proposed method can improve the precision of signal parameters and take less signal acquisition time than traditional serial search methods for global navigation satellite system (GNSS signals.

  19. Scaling and root planing with enhanced root planing on healthcare for type 2 diabetes mellitus: A randomized controlled clinical trial

    Directory of Open Access Journals (Sweden)

    Huihui Zhang

    2013-09-01

    Conclusion: This study suggests that SRP can be of benefit for the improvement of glycemic control and periodontal condition. In addition, ERP can further improve the periodontal condition of patients with T2DM.

  20. Fluid-Mediated Stochastic Self-Assembly at Centimetric and Sub-Millimetric Scales: Design, Modeling, and Control

    National Research Council Canada - National Science Library

    Haghighat, Bahar; Mastrangeli, Massimo; Mermoud, Grégory; Schill, Felix; Martinoli, Alcherio

    2016-01-01

    .... Numerous studies have been conducted on the control and modeling of the process in engineered self-assembling systems constituted of modules with varied capabilities ranging from completely reactive...

  1. Wind power integration into the automatic generation control of power systems with large-scale wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

    2014-01-01

    Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC......) of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs) and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described...... and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different...

  2. Assessment of long-term and large-scale even-odd license plate controlled plan effects on urban air quality and its implication

    Science.gov (United States)

    Zhao, Suping; Yu, Ye; Qin, Dahe; Yin, Daiying; He, Jianjun

    2017-12-01

    To solve traffic congestion and to improve urban air quality, long-lasting and large-scale even-odd license plate controlled plan was implemented by local government during 20 November to 26 December 2016 in urban Lanzhou, a semi-arid valley city of northwest China. The traffic control measures provided an invaluable opportunity to evaluate its effects on urban air quality in less developed cities of northwest China. Based on measured simultaneously air pollutants and meteorological parameters, the abatement of traffic-related pollutants induced by the implemented control measures such as CO, PM2.5 and PM10 (the particulate matter with diameter less than 2.5 μm and 10 μm) concentrations were firstly quantified by comparing the air quality data in urban areas with those in rural areas (uncontrolled zones). The concentrations of CO, NO2 from motor vehicles and fine particulate matter (PM2.5) were shown to have significant decreases of 15%-23% during traffic control period from those measured before control period with hourly maximum CO, PM2.5, and NO2/SO2 reduction of 43%, 35% and 141.4%, respectively. The influence of the control measures on AQI (air quality index) and ozone was less as compared to its effect on other air pollutants. Therefore, to alleviate serious winter haze pollution in China and to protect human health, the stringent long-term and large-scale even-odd license plate controlled plan should be implemented aperiodically in urban areas, especially for the periods with poor diffusion conditions.

  3. Large-Scale Controls of the Surface Water Balance Over Land: Insights From a Systematic Review and Meta-Analysis

    Science.gov (United States)

    Padrón, Ryan S.; Gudmundsson, Lukas; Greve, Peter; Seneviratne, Sonia I.

    2017-11-01

    The long-term surface water balance over land is described by the partitioning of precipitation (P) into runoff and evapotranspiration (ET), and is commonly characterized by the ratio ET/P. The ratio between potential evapotranspiration (PET) and P is explicitly considered to be the primary control of ET/P within the Budyko framework, whereas all other controls are often integrated into a single parameter, ω. Although the joint effect of these additional controlling factors of ET/P can be significant, a detailed understanding of them is yet to be achieved. This study therefore introduces a new global data set for the long-term mean partitioning of P into ET and runoff in 2,733 catchments, which is based on in situ observations and assembled from a systematic examination of peer-reviewed studies. A total of 26 controls of ET/P that are proposed in the literature are assessed using the new data set. Results reveal that: (i) factors controlling ET/P vary between regions with different climate types; (ii) controls other than PET/P explain at least 35% of the ET/P variance in all regions, and up to ˜90% in arid climates; (iii) among these, climate factors and catchment slope dominate over other landscape characteristics; and (iv) despite the high attention that vegetation-related indices receive as controls of ET/P, they are found to play a minor and often nonsignificant role. Overall, this study provides a comprehensive picture on factors controlling the partitioning of P, with valuable insights for model development, watershed management, and the assessment of water resources around the globe.

  4. Unbalance Compensation of a Full Scale Test Rig Designed for HTR-10GT: A Frequency-Domain Approach Based on Iterative Learning Control

    Directory of Open Access Journals (Sweden)

    Ying He

    2017-01-01

    Full Text Available Unbalance vibrations are crucial problems in heavy rotational machinery, especially for the systems with high operation speed, like turbine machinery. For the program of 10 MW High Temperature gas-cooled Reactor with direct Gas-Turbine cycle (HTR-10GT, the rated operation speed of the turbine system is 15000 RPM which is beyond the second bending frequency. In that case, even a small residual mass will lead to large unbalance vibrations. Thus, it is of great significance to study balancing methods for the system. As the turbine rotor is designed to be suspended by active magnetic bearings (AMBs, unbalance compensation could be achieved by adequate control strategies. In the paper, unbalance compensation for the Multi-Input and Multi-Output (MIMO active magnetic bearing (AMB system using frequency-domain iterative learning control (ILC is analyzed. Based on the analysis, an ILC controller for unbalance compensation of the full scale test rig, which is designed for the rotor and AMBs in HTR-10GT, is designed. Simulation results are reported which show the efficiency of the ILC controller for attenuating the unbalance vibration of the full scale test rig. This research can offer valuable design criterion for unbalance compensation of the turbine machinery in HTR-10GT.

  5. Stability and dewetting of metal nanoparticle filled thin polymer films: control of instability length scale and dynamics.

    Science.gov (United States)

    Mukherjee, Rabibrata; Das, Soma; Das, Anindya; Sharma, Satinder K; Raychaudhuri, Arup K; Sharma, Ashutosh

    2010-07-27

    We investigate the influence of gold nanoparticle addition on the stability, dewetting, and pattern formation in ultrathin polymer-nanoparticle (NP) composite films by examining the length and time scales of instability, morphology, and dynamics of dewetting. For these 10-50 nm thick (h) polystyrene (PS) thin films containing uncapped gold nanoparticles (diameter approximately 3-4 nm), transitions from complete dewetting to arrested dewetting to absolute stability were observed depending on the concentration of the particles. Experiments show the existence of three distinct stability regimes: regime 1, complete dewetting leading to droplet formation for nanoparticle concentration of 2% (w/w) or below; regime 2, partial dewetting leading to formation of arrested holes for NP concentrations in the range of 3-6%; and regime 3, complete inhibition of dewetting for NP concentrations of 7% and above. Major results are (a) length scale of instability, where lambdaH approximately hn remains unchanged with NP concentration in regime 1 (n approximately 2) but increases in regime 2 with a change in the scaling relation (n approximately 3-3.5); (b) dynamics of instability and dewetting becomes progressively sluggish with an increase in the NP concentration; (c) there are distinct regimes of dewetting velocity at low NP concentrations; (d) force modulation AFM, as well as micro-Raman analysis, shows phase separation and aggregation of the gold nanoparticles within each dewetted polymer droplet leading to the formation of a metal core-polymer shell morphology. The polymer shell could be removed by washing in a selective solvent, thus exposing an array of bare gold nanoparticle aggregates.

  6. The long-term effect on mental health symptoms and patient activation of using patient feedback scales in mental health out-patient treatment. A randomised controlled trial.

    Science.gov (United States)

    Rise, Marit By; Eriksen, Lasse; Grimstad, Hilde; Steinsbekk, Aslak

    2016-01-01

    To investigate the long-term effect on mental health symptoms and patient activation, from using the Partners for Change Outcome Management System (PCOMS) feedback scales in out-patient mental health consultations, compared to not using feedback scales. An open parallel-group randomised controlled trial was conducted in a mental health hospital in Norway. Eight therapists treated the intervention group, using two feedback scales, and seventeen therapists treated the treatment as usual group. Seventy-five patients participated. Six and twelve months after starting treatment there were no significant effects on the primary outcomes mental health symptoms or patient activation. Compared to baseline assessment the PCOMS group had significantly improved their patient activation scores after twelve months. We found no long-term effects from using the PCOMS scales on mental health symptoms or patient activation. This study shows that the use of a feedback system does not increase mental health outcomes or patient activation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Scale-up of a programme for malaria vector control using long-lasting insecticide-treated nets: lessons from South Sudan.

    Science.gov (United States)

    Chanda, Emmanuel; Remijo, Constantino D; Pasquale, Harriet; Baba, Samson P; Lako, Richard L

    2014-04-01

    Long-lasting insecticidal nets (LLINs) are important tools in malaria control. South Sudan, like many other endemic countries, has struggled to improve LLIN coverage and utilization. In 2006, Southern Sudan - known as South Sudan after independence in 2011 - initiated a strategic plan to increase LLIN coverage so that at least 60% of households had at least one LLIN each. By 2008, the target coverage was 80% of households and the Global Fund had financed a phased scale-up of LLIN distribution in the region. South Sudan's entire population is considered to be at risk of malaria. Poor control of the vectors and the large-scale movements of returnees, internally displaced people and refugees have exacerbated the problem. By 2012, approximately 8.0 million LLINs had been distributed in South Sudan. Between 2006 and 2009, the percentage of households possessing at least one LLIN increased from about 12% to 53% and LLIN utilization rates increased from 5 to 25% among children younger than 5 years and from 5 to 36% among pregnant women. The number of recorded malaria cases increased from 71 948 in 2008 to 1 198 357 in 2012. In post-conflict settings, a phased programme for the national scale-up of LLIN coverage may not have a substantial impact. A nationwide campaign that is centrally coordinated and based on sound guidelines may offer greater benefits. A strong partnership base and effective channels for the timely and supplementary deployment of LLINs may be essential for universal coverage.

  8. Application of In-line Focused Beam Reflectance Measurement to Brivanib Alaninate Wet Granulation Process to Enable Scale-up and Attribute-based Monitoring and Control Strategies.

    Science.gov (United States)

    Narang, Ajit S; Stevens, Timothy; Macias, Kevin; Paruchuri, Srinivasa; Gao, Zhihui; Badawy, Sherif

    2017-01-01

    Application of in-line real-time process monitoring using a process analytical technology for granule size distribution can enable quality-by-design development of a drug product and enable attribute-based monitoring and control strategies. In this study, an in-line laser focused beam reflectance measurement (FBRM) C35 probe was used to investigate the effect of formulation and process parameters on the granule growth profile over time during the high shear wet granulation of a high drug load formulation of brivanib alaninate. The probe quantitatively captured changes in the granule chord length distribution (CLD) with the progress of granulation and delineated the impact of water concentration used during granulation. The results correlated well with offline particle size distribution measured by nested sieve analyses. An end point indication algorithm was developed that was able to successfully track the process time needed to reach the target CLD. Testing of the brivanib alaninate granulation through 25-fold scale-up of the batch process indicated that the FBRM CLD profile can provide a scale-independent granule attribute-based process fingerprint. These studies highlight the ability of FBRM to quantitate a granule attribute of interest during wet granulation that can be used as an attribute-based scale-up and process monitoring and control parameter. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  9. Wind power integration into the automatic generation control of power systems with large-scale wind power

    Directory of Open Access Journals (Sweden)

    Abdul Basit

    2014-10-01

    Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

  10. Physiological controls of large‐scale patterning in planarian regeneration: a molecular and computational perspective on growth and form

    Science.gov (United States)

    Durant, Fallon; Lobo, Daniel; Hammelman, Jennifer

    2016-01-01

    Abstract Planaria are complex metazoans that repair damage to their bodies and cease remodeling when a correct anatomy has been achieved. This model system offers a unique opportunity to understand how large‐scale anatomical homeostasis emerges from the activities of individual cells. Much progress has been made on the molecular genetics of stem cell activity in planaria. However, recent data also indicate that the global pattern is regulated by physiological circuits composed of ionic and neurotransmitter signaling. Here, we overview the multi‐scale problem of understanding pattern regulation in planaria, with specific focus on bioelectric signaling via ion channels and gap junctions (electrical synapses), and computational efforts to extract explanatory models from functional and molecular data on regeneration. We present a perspective that interprets results in this fascinating field using concepts from dynamical systems theory and computational neuroscience. Serving as a tractable nexus between genetic, physiological, and computational approaches to pattern regulation, planarian pattern homeostasis harbors many deep insights for regenerative medicine, evolutionary biology, and engineering. PMID:27499881

  11. Implementation of a Large Scale Control System for a High-Energy Physics Detector: The CMS Silicon Strip Tracker

    CERN Document Server

    Masetti, Lorenzo; Fischer, Peter

    2011-01-01

    Control systems for modern High-Energy Physics (HEP) detectors are large distributed software systems managing a significant data volume and implementing complex operational procedures. The control software for the LHC experiments at CERN is built on top of a commercial software used in industrial automation. However, HEP specific requirements call for extended functionalities. This thesis focuses on the design and implementation of the control system for the CMS Silicon Strip Tracker but presents some general strategies that have been applied in other contexts. Specific design solutions are developed to ensure acceptable response times and to provide the operator with an effective summary of the status of the devices. Detector safety is guaranteed by proper configuration of independent hardware systems. A software protection mechanism is used to avoid the widespread intervention of the hardware safety and to inhibit dangerous commands. A wizard approach allows non expert operators to recover error situations...

  12. Large-Scale Synthesis of Transition-Metal-Doped TiO2 Nanowires with Controllable Overpotential

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bin; Chen, HaoMing; Liu, Chong; Andrews, Sean; Han, Chris; Yang, Peidong

    2013-03-13

    Practical implementation of one-dimensional semiconductors into devices capable of exploiting their novel properties is often hindered by low product yields, poor material quality, high production cost, or overall lack of synthetic control. Here, we show that a molten-salt flux scheme can be used to synthesize large quantities of high-quality, single-crystalline TiO2 nanowires with controllable dimensions. Furthermore, in situ dopant incorporation of various transition metals allows for the tuning of optical, electrical, and catalytic properties. With this combination of control, robustness, and scalability, the molten-salt flux scheme can provide high-quality TiO2 nanowires to satisfy a broad range of application needs from photovoltaics to photocatalysis.

  13. Advanced Control Strategies to Enable a More Wide-Scale Adoption of Single-Phase Photovoltaic Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng

    ) Modelling and Evaluation of Single-Phase PV Systems and 2) Advanced Control Strategies for Single-Phase PV Systems. The first part, including Chapters 2 and 3, describes the entire models of the most promising transformerless PV candidates (models of PV modules, inverters, and filters) in Chapter 2. Then...... and lifetime prediction based on mission profiles (e.g. solar irradiance level and ambient temperature) has been proposed. Grid detection and synchronization techniques have also been discussed in Chapter 2, since they are of importance in the control of single-phase systems both in normal operation mode...

  14. Microbiological, Geochemical and Hydrologic Processes Controlling Uranium Mobility: An Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado, Quality Assurance Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    Fix, N. J.

    2008-01-07

    The U.S. Department of Energy (DOE) is cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as uranium and chromium, whose mobility and solubility change with redox status. Field-scale experiments with acetate as the electron donor have stimulated metal-reducing bacteria to effectively remove uranium [U(VI)] from groundwater at the Uranium Mill Tailings Site in Rifle, Colorado. The Pacific Northwest National Laboratory and a multidisciplinary team of national laboratory and academic collaborators has embarked on a research proposed for the Rifle site, the object of which is to gain a comprehensive and mechanistic understanding of the microbial factors and associated geochemistry controlling uranium mobility so that DOE can confidently remediate uranium plumes as well as support stewardship of uranium-contaminated sites. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by the Rifle Integrated Field-Scale Subsurface Research Challenge Project.

  15. Small-scale combined heat and power as a balancing reserve for wind – The case of participation in the German secondary control reserve

    Directory of Open Access Journals (Sweden)

    Peter Sorknæs

    2014-06-01

    Full Text Available Increasing amounts of intermittent renewable energy sources (RES are being integrated into energy systems worldwide. Due to the nature of these sources, they are found to increase the importance of mechanisms for balancing the electricity system. Small-scale combined heat and power (CHP plants based on gas have proven their ability to participate in the electricity system balancing, and can hence be used to facilitate an integration of intermittent RES into electricity systems. Within the EU electricity system, balancing reserves have to be procured on a market basis. This paper investigates the ability and challenges of a small-scale CHP plant based on natural gas to participate in the German balancing reserve for secondary control. It is found that CHP plants have to account for more potential losses than traditional power plants. However, it is also found that the effect of these losses can be reduced by increasing the flexibility of the CHP unit.

  16. Exploring the use of routinely-available, retrospective data to study the association between malaria control scale-up and micro-economic outcomes in Zambia.

    Science.gov (United States)

    Comfort, Alison; Leegwater, Anthony; Nakhimovsky, Sharon; Kansembe, Henry; Hamainza, Busiku; Bwalya, Benson; Alilio, Martin; Johns, Ben; Olsho, Lauren

    2017-01-04

    Country-level evidence on the impact of malaria control on micro-economic outcomes is vital for mobilizing domestic and donor resources for malaria control. Using routinely available survey data could facilitate this investigation in a cost-efficient way. The authors used Malaria Indicator Surveys (MIS) and Living Conditions Monitoring Survey (LCMS) data from 2006 to 2010 for all 72 districts in Zambia to relate malaria control scale-up with household food spending (proxy for household well-being), educational attainment and agricultural production. The authors used two quasi-experimental designs: (1) a generalized propensity score for a continuous treatment variable (defined as coverage from owning insecticide-treated bed nets and/or receipt of indoor residual spraying); and, (2) a district fixed effects model to assess changes in the outcome relative to changes in treatment pre-post scale-up. The unit of analysis was at district level. The authors also conducted simulations post-analysis to assess statistical power. Micro-economic outcomes increased (33% increase in food spending) concurrently with malaria control coverage (62% increase) from 2006 to 2010. Despite using data from all 72 districts, both analytic methods yielded wide confidence intervals that do not conclusively link outcomes and malaria control coverage increases. The authors cannot rule out positive, null or negative effects. The upper bound estimates of the results show that if malaria control coverage increases from 60 to 70%, food spending could increase up to 14%, maize production could increase up to 57%, and years of schooling could increase up to 0.5 years. Simulations indicated that the generalized propensity score model did not have good statistical power. While it is technically possible to use routinely available survey data to relate malaria control scale-up and micro-economic outcomes, it is not clear from this analysis that meaningful results can be obtained when survey data are

  17. Scaling control in superficial installations at the Las Tres Virgenes, geothermal field, BCS; Control de incrustacion en instalaciones superficiales del campo geotermico de Las Tres Virgenes, BCS

    Energy Technology Data Exchange (ETDEWEB)

    Tapia Salazar, Ruth [Comision Federal de Electricidad (Mexico)]. E-mail: ruth.tapia@cfe.gob.mx

    2007-01-15

    Silica scaling is one of the most important problems in the Las Tres Virgenes geothermal field. It affects not only the superficial installations, like brine injection pipelines, but also the injection wells where it reduces injection capacity. Separated brine passes from production wells to injection wells by means of steel pipelines 10 and 14 inches in diameter. The pipelines are affected by silica scaling that occurs when the two-phase fluid is discharged at atmospheric pressure and the separated brine is cooled and concentrated and then over saturated with amorphous silica. Even when the pipelines were cleaned periodically, it was necessary to implement a technique for prevent scaling. Two methods considered appropriate to the specific field conditions were studied, and finally the technique of modifying the brine pH was adopted. After over a year of using this technique in the general injection system, no mechanical cleaning of the pipelines has been necessary-and once cleaning was needed at least every third day. This represents an important improvement in the steam supply system. [Spanish] Uno de los problemas mas importantes en el campo geotermico de Las Tres Virgenes es la incrustacion por silice, la cual afecta no solo a instalaciones superficiales como lineas de inyeccion de salmuera, sino tambien a los pozos inyectores al reducir su capacidad de aceptacion. El agua producida por los pozos productores se conduce hasta los pozos inyectores por medio de tuberias de acero al carbon de 10 y 14 pulgadas de diametro, que se ven afectadas por la incrustacion de silice. La incrustacion ocurre debido a que cuando el fluido en dos fases es descargado a presion atmosferica, la salmuera separada, enfriada y concentrada, esta usualmente sobresaturada con respecto a la solubilidad de la silice amorfa. Aunque las tuberias se limpiaban mecanicamente, fue necesario seleccionar una tecnica para prevenir la incrustacion, para lo cual se estudiaron dos de los metodos que

  18. An assessment of the effectiveness of a large, national-scale invasive alien plant control strategy in South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2012-04-01

    Full Text Available efforts on the extent of invasion of these taxa was assessed. Control costs over 15 years amounted to 3.2 billion rands (US$457 million), more than half of which was spent on 10 taxa, the most prominent being in the genera Acacia, Prosopis, Pinus...

  19. Large scale experience with industrial stepping motor controllers and resolver read-out systems at SPS and LEP

    CERN Document Server

    Colchester, R J; Jung, R; Koopman, J; Vouillot, J M; Feres, J; López, B

    1996-01-01

    Over three hundred stepping motors and two hundred resolvers are used for Beam Instrumentation purposes in SPS and LEP. Most of these instruments are beam intercepting and therefore require very reliable drive electronics. The coincidence of the upgrading of the SPS controls and of the energy upgrade of LEP was the ideal opportunity to standardise the motor control systems for both accelerators and to acquire an industrial system which would fulfil the requirements for the two machines in the most economical way. The interface to the control system had to be compatible with different environments, currently PCs in the SPS and VME crates in LEP and probably other systems in the future. The project was handled as a farming-out project with CERN producing a detailed functional specification and the hardware development being entirely under the responsibility of industry. The first set of motors and resolvers has been equipped with the new control systems and has been running for more than one and a half years wi...

  20. Organization of the Human Frontal Pole Revealed by Large-Scale DTI-Based Connectivity: Implications for Control of Behavior

    National Research Council Canada - National Science Library

    Orr, Joseph M; Smolker, Harry R; Banich, Marie T

    2015-01-01

    ... cognition [7], yet, there is little consensus with regards to a detailed theory of its functioning. One hypothesis, the gateway hypothesis, suggests that the frontal pole (FP) acts as a supervisory attentional control system that selects between attending to internal ('stimulus-independent') information, or attending to external ('...

  1. Lack of serological evidence for Mycoplasma fermentans infection in army Gulf War veterans: a large scale case-control study.

    Science.gov (United States)

    Lo, S C; Levin, L; Ribas, J; Chung, R; Wang, R Y; Wear, D; Shih, J W

    2000-12-01

    Mycoplasma firmentans is suspected in the development of 'Gulf War illness' in veterans of Operation Desert Storm. We conducted a matched case-control study for the prevalence of M. firmentans-specific antibodies before and after the operation, as well as seroconversion rates in veterans with and without complaints of 'Gulf War illness'. Cases consisted of Gulf War veterans, who complained of various illnesses and were enrolled in the second phase of the health evaluation by the Army Comprehensive Clinical Examination Program (CCEP). Controls were selected from Gulf War veterans who did not participate in the registry and did not request a health evaluation by the CCEP. Before operation deployment, 34 out of 718 of the cases (48%) and 116 out of 2233 of the controls (5.2%) tested positive for M. fermentans-specific antibodies. There was no difference in rates of seroconversion between cases and controls (1.1 vs. 1.2%) to M. fermentans during Operation Desert Storm. Thus, there is no serological evidence that suggests infectionby M. fermentans is associated with development of 'Gulf War illness'.

  2. Using a stochastic model and cross-scale analysis to evaluate controls on historical low-severity fire regimes

    Science.gov (United States)

    Maureen C. Kennedy; Donald. McKenzie

    2010-01-01

    Fire-scarred trees provide a deep temporal record of historical fire activity, but identifying the mechanisms therein that controlled landscape fire patterns is not straightforward. We use a spatially correlated metric for fire co-occurrence between pairs of trees (the Sørensen distance variogram), with output from a neutral model for fire history, to infer the...

  3. Robustness Analysis for Indoor Lighting Systems : An Application of Model Checking in Large-Scale Distributed Control Systems

    NARCIS (Netherlands)

    Doornbos, R.; Verriet, J.; Verberkt, M.

    2015-01-01

    Modern lighting systems are configurable systems-of-systems that have to operate in an environment that they cannot fully control. These systems have to guarantee the continuation of their functionality regardless of the events in their environment. As testing and simulation are not able to identify

  4. An Integrated, Multi-Stage, Multi-Scale Framework for Achieving Sustainable Process Synthesis-Intensification-Control

    DEFF Research Database (Denmark)

    Babi, Deenesh Kavi; Kumar Tula, Anjan; Mansouri, Seyed Soheil

    a major role because it provides the opportunity to perform the same tasks in a more sustainable way, new/novel unit operations can be generated (Lutze et al, 2013) and more sustainable processes can be designed (Babi et al., 2014). An integrated, multi-stage, multi-scale, computer-aided framework has...... is analysed using economic and sustainability analyses in order to identify process limitations (hot-spots) that are translated into intensification design targets. In stage 3, an integrated task-phenomena-based synthesis-intensification method is embedded and applied (Babi et al., 2015) that consists......The chemical and biochemical industry needs major reductions in energy consumption, waste generation, etc., in order to remain competitive through the design and operation of more sustainable chemical and biochemical processes. These required reductions can be addressed through process synthesis...

  5. A mechanistic ecohydrological model to investigate complex interactions in cold and warm water-controlled environments. 1. Theoretical framework and plot-scale analysis

    Directory of Open Access Journals (Sweden)

    Simone Fatichi

    2012-05-01

    Full Text Available Numerous studies have explored the role of vegetation in controlling and mediating hydrological states and fluxes at the level of individual processes, which has led to improvements in our understanding of plot-scale dynamics. Relatively less effort has been directed toward spatially-explicit studies of vegetation-hydrology interactions at larger scales of a landscape.Only few continuous, process-oriented ecohydrological models had been proposed with structures of varying complexity. This study contributes to their further evolution and presents a novel ecohydrological model, {it Tethys-Chloris}. The model synthesizes the state-of-the-art knowledge on individual processes and coupling mechanisms drawn from the disciplines of hydrology, plant physiology, and ecology. Specifically, the model reproduces all essential components of the hydrological cycle: it resolves the mass and energy budgets in the atmospheric surface layer at the hourly scale, while representing up to two layers of vegetation; it includes a module of snowpack evolution; it describes the saturated and unsaturated soil water dynamics, processes of runoff generation and flow routing. The component of vegetation dynamics parameterizes lifecycle processes of different plant functional types, including photosynthesis, phenology, carbon allocation, and tissue turnover. This study presents a confirmation of the long-term, plot-scale model performance by simulating two types of ecosystems corresponding to different climate conditions. A consistent and highly satisfactory model skill in reproducing the energy and water budgets as well as physiological cycles of plants with minimum calibration overhead is demonstrated.Furthermore, these applications demonstrate that the model permits the identification of data types and observation frequencies crucial for appropriate evaluation of modeled dynamics. More importantly, through a synthesis of a wide array of process representations, the model

  6. Aquifer-scale controls on the distribution of nitrate and ammonium in ground water near La Pine, Oregon, USA

    Science.gov (United States)

    Hinkle, S.R.; Böhlke, J.K.; Duff, J.H.; Morgan, D.S.; Weick, R.J.

    2007-01-01

    Geochemical and isotopic tools were applied at aquifer, transect, and subtransect scales to provide a framework for understanding sources, transport, and fate of dissolved inorganic N in a sandy aquifer near La Pine, Oregon. NO3 is a common contaminant in shallow ground water in this area, whereas high concentrations of NH4-N (up to 39 mg/L) are present in deep ground water. N concentrations, N/Cl ratios, tracer-based apparent ground-water ages, N isotope data, and hydraulic gradients indicate that septic tank effluent is the primary source of NO3. N isotope data, N/Cl and N/C relations, 3H data, and hydraulic considerations point to a natural, sedimentary organic matter source for the high concentrations of NH4, and are inconsistent with an origin as septic tank N. Low recharge rates and flow velocities have largely restricted anthropogenic NO3 to isolated plumes within several meters of the water table. A variety of geochemical and isotopic data indicate that denitrification also affects NO3 gradients in the aquifer. Ground water in the La Pine aquifer evolves from oxic to increasingly reduced conditions. Suboxic conditions are achieved after about 15-30 y of transport below the water table. NO3 is denitrified near the oxic/suboxic boundary. Denitrification in the La Pine aquifer is characterized well at the aquifer scale with a redox boundary approach that inherently captures spatial variability in the distribution of electron donors. ?? 2006 Elsevier B.V. All rights reserved.

  7. Development and psychometric testing of the Attitudes, Subjective Norms, Perceived Behavioural Control, and Intention to Pursue a Career in Mental Health Nursing scale.

    Science.gov (United States)

    Wilbourn, Mark; Salamonson, Yenna; Ramjan, Lucie; Chang, Sungwon

    2017-01-19

    The aim of the present study was to develop and test the psychometric properties of the Attitudes, Subjective Norms, Perceived Behavioural Control, and Intention to Pursue a Career in Mental Health Nursing (ASPIRE) scale, an instrument to assess nursing students' intention to work in mental health nursing. Understanding the factors influencing undergraduate nursing students' career intentions might lead to improved recruitment strategies. However, there are no standardized tools to measure and assess students' intention to pursue a career in mental health nursing. The present study used a cross-sectional survey design undertaken at a large tertiary institution in Western Sydney (Australia) between May and August 2013. It comprised three distinct and sequential phases: (i) items were generated representing the four dimensions of the theory of planned behaviour; (ii) face and content validity were tested by a representative reference group and panel of experts; and (iii) survey data from 1109 first- and second-year and 619 third-year students were used in exploratory and confirmatory factor analyses to test the factorial validity of the scale. Internal consistency was measured using Cronbach's alpha. Items generated for the ASPIRE scale were subject to face and content validity testing. Results showed good factorial validity and reliability for the final 14-item scale. Principal axis factoring revealed a one-factor solution, the hypothesized model being supported by confirmatory factor analysis. The ASPIRE scale is a valid and reliable instrument for measuring intention to pursue a career in mental health nursing among Bachelor of Nursing students. © 2017 Australian College of Mental Health Nurses Inc.

  8. Sitting Phase Monolayers of Polymerizable Phospholipids Create Dimensional, Molecular-Scale Wetting Control for Scalable Solution-Based Patterning of Layered Materials.