WorldWideScience

Sample records for highly challenging control

  1. Control challenges in domestic heating systems

    DEFF Research Database (Denmark)

    Thybo, Honglian; Larsen, Lars F. S.; Weitzmann, Peter

    2007-01-01

    The objective of this paper is to analyze domestic heating applications and identify unfavorable building constructions and control challenges to be addressed by high performance heating control systems. Heating of domestic houses use a large amount of the total energy consumption in Scandinavia....... Hence the potential of reducing energy consumption by applying high performance control is vast. Indoor climate issues are becoming more in focus, which also leads to a demand for high performance heating systems. The paper presents an analysis of how the building elements of today's domestic houses...... with water based floor heating affect the control challenge. The analysis is documented with simulation results....

  2. Deep Space Control Challenges of the New Millennium

    Science.gov (United States)

    Bayard, David S.; Burdick, Garry M.

    1999-01-01

    The exploration of deep space presents a variety of significant control challenges. Long communication delays coupled with challenging new science objectives require high levels of system autonomy and increasingly demanding pointing and control capabilities. Historically, missions based on the use of a large single spacecraft have been successful and popular since the early days of NASA. However, these large spacecraft missions are currently being displaced by more frequent and more focused missions based on the use of smaller and less expensive spacecraft designs. This trend drives the need to design smart software and good algorithms which together with the miniaturization of control components will improve performance while replacing the heavier and more expensive hardware used in the past. NASA's future space exploration will also include mission types that have never been attempted before, posing significant challenges to the underlying control system. This includes controlled landing on small bodies (e.g., asteroids and comets), sample return missions (where samples are brought back from other planets), robotic exploration of planetary surfaces (e.g., intelligent rovers), high precision formation flying, and deep space optical interferometry, While the control of planetary spacecraft for traditional flyby and orbiter missions are based on well-understood methodologies, control approaches for many future missions will be fundamentally different. This paradigm shift will require completely new control system development approaches, system architectures, and much greater levels of system autonomy to meet expected performance in the presence of significant environmental disturbances, and plant uncertainties. This paper will trace the motivation for these changes and will layout the approach taken to meet the new challenges. Emerging missions will be used to explain and illustrate the need for these changes.

  3. The Challenge of Recruiting Control Groups

    DEFF Research Database (Denmark)

    O'Connor, Maja

    2011-01-01

    . This study was a direct reaction to the first recruitment attempt that had a 10% response rate. This study consisted of four groups of randomly selected elderly married people (65-81 years) receiving a postal questionnaire measuring depression, social support, coping style, adult attachment, life......  Recruitment of a large and reliable control group is a challenge in psychological survey based research. The effect of recruitment styles and age on response-rate, data quality, and individual differences were investigated in a control group for a postal survey of elderly bereaved people...... incentive had the highest response-rate (51%), good data quality, and no sampling bias in individual differences. This method can be highly recommended in future control group recruitment....

  4. Design Challenges Encountered in a Propulsion-Controlled Aircraft Flight Test Program

    Science.gov (United States)

    Maine, Trindel; Burken, John; Burcham, Frank; Schaefer, Peter

    1994-01-01

    The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flightpath and bank angle using only commands to the throttles. Although the program was highly successful, this paper highlights some of the challenges associated with using engine thrust as a control effector. These challenges include slow engine response time, poorly modeled nonlinear engine dynamics, unmodeled inlet-airframe interactions, and difficulties with ground effect and gust rejection. Flight and simulation data illustrate these difficulties.

  5. Nanoparticles for mosquito control: Challenges and constraints

    Directory of Open Access Journals (Sweden)

    Giovanni Benelli

    2017-10-01

    Full Text Available Mosquito control programs are facing important and timely challenges, including the recent outbreaks of novel arbovirus, the development of resistance in several Culicidae species, and the rapid spreading of highly invasive mosquitoes worldwide. Current control tools mainly rely on the employment of (i synthetic or microbial pesticides, (ii insecticide-treated bed nets, (iii adult repellents, (iv biological control agents against mosquito young instars (mainly fishes, amphibians and copepods (v Sterile Insect Technique (SIT, (vi “boosted SIT”, (vii symbiont-based methods and (viii transgenic mosquitoes. Currently, none of these single strategies is fully successful. Novel eco-friendly strategies to manage mosquito vectors are urgently needed. The plant-mediated fabrication of nanoparticles is advantageous over chemical and physical methods, since it is cheap, single-step, and does not require high pressure, energy, temperature, or the use of highly toxic chemicals. In the latest years, a growing number of plant-borne compounds have been proposed for efficient and rapid extracellular synthesis of metal nanoparticles effective against mosquitoes at very low doses (i.e. 1–30 ppm. In this review, we focused on the promising potential of green-fabricated nanoparticles as toxic agents against mosquito young instars, and as adult oviposition deterrents. Furthermore, we analyzed current evidences about non-target effects of these nanocomposites used for mosquito control, pointing out their moderate acute toxicity for non-target aquatic organisms, absence of genotoxicity at the doses tested against mosquitoes, and the possibility to boost the predation rates of biological control agents against mosquitoes treating the aquatic environment with ultra-low doses (e.g. 1–3 ppm of green-synthesized nanoparticles, which reduce the motility of mosquito larvae. Challenges for future research should shed light on (i the precise mechanism(s of action of

  6. A Radio-Controlled Car Challenge

    Science.gov (United States)

    Roman, Harry T.

    2010-01-01

    Watching a radio-controlled car zip along a sidewalk or street has become a common sight. Within this toy are the basic ingredients of a mobile robot, used by industry for a variety of important and potentially dangerous tasks. In this challenge, students consider modifying an of-the-shelf, radio-controlled car, adapting it for a robotic task.

  7. The Need and Challenges for Distributed Engine Control

    Science.gov (United States)

    Culley, Dennis E.

    2013-01-01

    The presentation describes the challenges facing the turbine engine control system. These challenges are primarily driven by a dependence on commercial electronics and an increasingly severe environment on board the turbine engine. The need for distributed control is driven by the need to overcome these system constraints and develop a new growth path for control technology and, as a result, improved turbine engine performance.

  8. Model-based nonlinear control of hydraulic servo systems: Challenges, developments and perspectives

    Science.gov (United States)

    Yao, Jianyong

    2018-06-01

    Hydraulic servo system plays a significant role in industries, and usually acts as a core point in control and power transmission. Although linear theory-based control methods have been well established, advanced controller design methods for hydraulic servo system to achieve high performance is still an unending pursuit along with the development of modern industry. Essential nonlinearity is a unique feature and makes model-based nonlinear control more attractive, due to benefit from prior knowledge of the servo valve controlled hydraulic system. In this paper, a discussion for challenges in model-based nonlinear control, latest developments and brief perspectives of hydraulic servo systems are presented: Modelling uncertainty in hydraulic system is a major challenge, which includes parametric uncertainty and time-varying disturbance; some specific requirements also arise ad hoc difficulties such as nonlinear friction during low velocity tracking, severe disturbance, periodic disturbance, etc.; to handle various challenges, nonlinear solutions including parameter adaptation, nonlinear robust control, state and disturbance observation, backstepping design and so on, are proposed and integrated, theoretical analysis and lots of applications reveal their powerful capability to solve pertinent problems; and at the end, some perspectives and associated research topics (measurement noise, constraints, inner valve dynamics, input nonlinearity, etc.) in nonlinear hydraulic servo control are briefly explored and discussed.

  9. Of Radicals and DREAMers: Harnessing Exceptionality to Challenge Immigration Control

    Science.gov (United States)

    Heredia, Luisa Laura

    2015-01-01

    This article contributes to the literature on undocumented youth activism and citizenship by assessing undocumented youth's challenges to a growing regime of migration control in the US. It uses Doug McAdam's tactical interaction as an analytical lens to explore two consecutive high-risk campaigns, ICE infiltrations and expulsion/re-entry. In this…

  10. A long-acting integrase inhibitor protects female macaques from repeated high-dose intravaginal SHIV challenge.

    Science.gov (United States)

    Andrews, Chasity D; Yueh, Yun Lan; Spreen, William R; St Bernard, Leslie; Boente-Carrera, Mar; Rodriguez, Kristina; Gettie, Agegnehu; Russell-Lodrigue, Kasi; Blanchard, James; Ford, Susan; Mohri, Hiroshi; Cheng-Mayer, Cecilia; Hong, Zhi; Ho, David D; Markowitz, Martin

    2015-01-14

    Long-acting GSK1265744 (GSK744 LA) is a strand transfer inhibitor of the HIV/SIV (simian immunodeficiency virus) integrase and was shown to be an effective preexposure prophylaxis (PrEP) agent in a low-dose intrarectal SHIV (simian-human immunodeficiency virus) rhesus macaque challenge model. We examined the pharmacokinetics and efficacy of GSK744 LA as PrEP against repeat high-dose intravaginal SHIV challenge in female rhesus macaques treated with Depo-Provera (depot medroxyprogesterone acetate), which promotes viral transmission vaginally. When Depo-Provera-treated female rhesus macaques were dosed with GSK744 LA (50 mg/kg) monthly, systemic and tissue drug concentrations were lower than previously observed in male rhesus macaques. GSK744 concentrations were fivefold lower on average in cervical tissues than in rectal tissues. Eight female rhesus macaques were treated with GSK744 LA at week 0, and four female rhesus macaques served as controls. All animals received a high-dose challenge of SHIV162P3 at week 1. No infection was detected in GSK744 LA-treated rhesus macaques, whereas viremia was detected 1 to 2 weeks after SHIV challenge in all control animals. The GSK744 LA-treated rhesus macaques were given a second administration of drug at week 4 and further challenged at weeks 5 and 7. GSK744 LA treatment protected six of eight female rhesus macaques against three high-dose SHIV challenges, whereas all control animals became infected after the first challenge (P = 0.0003, log-rank test). These results support further clinical development of GSK744 LA for PrEP. Copyright © 2015, American Association for the Advancement of Science.

  11. Technological and licensing challenges for high burnup fuel

    International Nuclear Information System (INIS)

    Gross, H.; Urban, P.; Fenzlein, C.

    2002-01-01

    Deregulation of electricity markets is driving electricity prices downward as well in the U.S. as in Europe. As a consequence high burnup fuel will be demanded by utilities using either the storage or the reprocessing option. At a minimum, burnups consistent with the current political enrichment limit of 5 w/o will be required for both markets.Significant progress has been achieved in the past by Siemens in meeting the demands of utilities for increased fuel burnup. The technological challenges posed by the increased burnup are mainly related to the corrosion and hydrogen pickup of the clad, the high burnup properties of the fuel and the dimensional changes of the fuel assembly structure. Clad materials with increased corrosion resistance appropriate for high burnup have been developed. The high burnup behaviour of the fuel has been extensively investigated and the decrease of thermal conductivity with burnup, the rim effect of the pellet and the increase of fission gas release with burnup can be described, with good accuracy, in fuel rod computer codes. Advanced statistical design methods have been developed and introduced. Materials with increased corrosion resistance are also helpful controlling the dimensional changes of the fuel assembly structure. In summary, most of the questions about the fuel operational behaviour and reliability in the high burnup range have been solved - some of them are still in the process of verification - or the solutions are visible. This fact is largely acknowledged by regulators too. The main licensing challenges for high burnup fuel are currently seen for accident condition analyses, especially for RIA and LOCA. (author)

  12. Challenges to nuclear export controls today

    International Nuclear Information System (INIS)

    Chatelus, R.; Sevini, F.; Janssens, W.; Michel, Q.

    2014-01-01

    Nuclear energy and nuclear proliferation programs are potentially inter-twinned, which is a point to be taken into account when analysing the development of civil nuclear energy, both domestically and as foreign investment. International agreements ensure that the adhering countries fulfil their obligations and do not abuse civil nuclear programs for the production of nuclear weapons. Uranium enrichment is the process currently most focused on in this respect by recent news and recent technological and commercial developments. But also the so-called reactor-based pathway, with extraction of plutonium from spent nuclear fuel by reprocessing remains in the spotlight of inspectors. Two of the main and complementary pillars on which the prevention of such diversion relies, are Strategic Export Control and International Safeguards. Strategic export control is a key barrier against nuclear proliferation. In many countries including the EU, it is set by a legal framework, envisaging implementation, enforcement and prosecution. The goods that can exported only with authorisations are those identified by the international export control regimes; primarily the Nuclear Suppliers Group in the case of nuclear items. It is complemented by nuclear safeguards measures, and especially in the past few years, by the IAEA State Level concept, which looks at the overall country's potential, including its industrial structure to derive conclusions on the absence of undeclared activities. However, the strict control of goods and knowledge is a moving target, since technological developments, globalisation and the intensifying exchange of information via the worldwide web offer increasing opportunities to proliferators to acquire sensitive items and competencies, and create bigger challenges to enforcement, calling for new responses. Research and development programmes must be directed towards supporting the adaptation of current proliferation containment systems to these new

  13. Prevention and control of rheumatic heart disease: Overcoming core challenges in resource-poor environments

    Science.gov (United States)

    Dougherty, Scott; Beaton, Andrea; Nascimento, Bruno R; Zühlke, Liesl J; Khorsandi, Maziar; Wilson, Nigel

    2018-01-01

    Rheumatic heart disease (RHD) has long receded as a significant threat to public health in high-income countries. In low-resource settings, however, the specter of RHD remains unabated, as exemplified by recent data from the Global Burden of Diseases Study. There are many complex reasons for this ongoing global disparity, including inadequate data on disease burden, challenges in effective advocacy, ongoing poverty and inequality, and weak health systems, most of which predominantly affect developing nations. In this review, we discuss how each of these acts as a core challenge in RHD prevention and control. We then examine key lessons learnt from successful control programs in the past and highlight resources that have been developed to help create strong national RHD control programs. PMID:29440834

  14. NASA flight controllers - Meeting cultural and leadership challenges on the critical path to mission success

    Science.gov (United States)

    Clement, James L., Jr.; Ritsher, Jennifer Boyd

    2006-01-01

    As part of its preparation for missions to the Moon and Mars, NASA has identified high priority critical path roadmap (CPR) questions, two of which focus on the performance of mission control personnel. NASA flight controllers have always worked in an incredibly demanding setting, but the International Space Station poses even more challenges than prior missions. We surveyed 14 senior ISS flight controllers and a contrasting sample of 12 more junior controllers about the management and cultural challenges they face and the most effective strategies for addressing them. There was substantial consensus among participants on some issues, such as the importance of building a personal relationship with Russian colleagues. Responses from junior and senior controllers differed in some areas, such as training. We frame the results in terms of two CPR questions. We aim to use our results to improve flight controller training.

  15. Challenges for remote monitoring and control of small reactors

    Energy Technology Data Exchange (ETDEWEB)

    Trask, D., E-mail: traskd@aecl.ca [Atomic Energy of Canada Limited, Fredericton, New Brunswick (Canada)

    2013-07-01

    This paper considers a model for small, unmanned, remotely located reactors and discusses the ensuing cyber security and operational challenges for monitoring and control and how these challenges might be overcome through some of AECL's research initiatives and experience. (author)

  16. International trade agreements challenge tobacco and alcohol control policies.

    Science.gov (United States)

    Zeigler, Donald W

    2006-11-01

    This report reviews aspects of trade agreements that challenge tobacco and alcohol control policies. Trade agreements reduce barriers, increase competition, lower prices and promote consumption. Conversely, tobacco and alcohol control measures seek to reduce access and consumption, raise prices and restrict advertising and promotion in order to reduce health and social problems. However, under current and pending international agreements, negotiated by trade experts without public health input, governments and corporations may challenge these protections as constraints on trade. Advocates must recognise the inherent conflicts between free trade and public health and work to exclude alcohol and tobacco from trade agreements. The Framework Convention on Tobacco Control has potential to protect tobacco policies and serve as a model for alcohol control.

  17. Verification and Validation Challenges for Adaptive Flight Control of Complex Autonomous Systems

    Science.gov (United States)

    Nguyen, Nhan T.

    2018-01-01

    Autonomy of aerospace systems requires the ability for flight control systems to be able to adapt to complex uncertain dynamic environment. In spite of the five decades of research in adaptive control, the fact still remains that currently no adaptive control system has ever been deployed on any safety-critical or human-rated production systems such as passenger transport aircraft. The problem lies in the difficulty with the certification of adaptive control systems since existing certification methods cannot readily be used for nonlinear adaptive control systems. Research to address the notion of metrics for adaptive control began to appear in the recent years. These metrics, if accepted, could pave a path towards certification that would potentially lead to the adoption of adaptive control as a future control technology for safety-critical and human-rated production systems. Development of certifiable adaptive control systems represents a major challenge to overcome. Adaptive control systems with learning algorithms will never become part of the future unless it can be proven that they are highly safe and reliable. Rigorous methods for adaptive control software verification and validation must therefore be developed to ensure that adaptive control system software failures will not occur, to verify that the adaptive control system functions as required, to eliminate unintended functionality, and to demonstrate that certification requirements imposed by regulatory bodies such as the Federal Aviation Administration (FAA) can be satisfied. This presentation will discuss some of the technical issues with adaptive flight control and related V&V challenges.

  18. Reported challenges in nurse-led randomised controlled trials

    DEFF Research Database (Denmark)

    Wang Vedelø, Tina; Lomborg, Kirsten

    2011-01-01

    Aims: The purpose of this integrative literature review was to explore and discuss the methodological challenges nurse researchers report after conducting nurse-led randomised controlled trials in clinical hospital settings. Our research questions were (i) what are the most commonly experienced...... and the clinical nursing staff. Two lessons learned from this integrative review can be highlighted. First, we recommend researchers openly to share their experiences of barriers and challenges. They should describe factors that may have inhibited the desired outcome. Second, efforts to improve the collaboration...... between nurse researchers and clinicians, including education, training and support may increase the success rate and quality of nurse-led studies using the randomised controlled trial....

  19. Immigrants and health system challenges to TB control in Oman

    Directory of Open Access Journals (Sweden)

    Fochsen Grethe

    2010-07-01

    Full Text Available Abstract Background During the past three decades, Oman has made significant progress in controlling TB within it's borders. However, the national TB control program elimination target has yet to be reached. This study aims to explore the perceived roles played by the immigrant population and the private health sector in relation to TB control in Oman. Methods We conducted seventeen interviews with different health care providers. The verbatim transcripts were processed using content analysis. Results Three main themes emerged. Firstly the threat of repatriation faced by underprivileged expatriates, secondly the criticized and forgotten private health sector as a key player and thirdly the user and provider barriers faced by Omani patients in the Omani public health system. Conclusions The study has identified some of the challenges and barriers to TB control in Oman. These challenges are mainly related to unintended negative consequences arising from the current repatriation policy of immigrants and to and the lack of involvement of the private sector in TB control. TB control strategies designed to address these challenges are needed, for Oman to reach its TB elimination targets.

  20. Quality control in diagnostic radiology: experience and challenges

    International Nuclear Information System (INIS)

    Abd Aziz Mhd Ramli; Mohd Ramli Arshad; Mohd Khalid Matori; Muhammad Jamal Md Isa; Husaini Salleh; Abdullah Tahir Aliyasak; Zainal Jamaluddin; Hasrul Hisham Hussain

    2005-01-01

    Malaysian Institute for Nuclear Technology Research through its Medical Physics Group has been providing Quality Control (QC) services for medical x-ray apparatus used in diagnostic radiology to private clinics and hospitals since the year 1997. The quality control (QC) in diagnostic radiology is considered as part of quality assurance program which provide accurate diagnostic information at the lowest cost and the least exposure of the patients to radiation. Many experience and obstacles were faced by Medical Physics Group. This paper will discuss on some of the experiences and challenges that could be shared together with MINT staff especially in the safety aspect related to electrical and mechanical, radiation protection, performance and standard. The challenging in administrative aspect also will discuss. (Author)

  1. Human factors challenges for advanced process control

    International Nuclear Information System (INIS)

    Stubler, W.F.; O'Hara, J..M.

    1996-01-01

    New human-system interface technologies provide opportunities for improving operator and plant performance. However, if these technologies are not properly implemented, they may introduce new challenges to performance and safety. This paper reports the results from a survey of human factors considerations that arise in the implementation of advanced human-system interface technologies in process control and other complex systems. General trends were identified for several areas based on a review of technical literature and a combination of interviews and site visits with process control organizations. Human factors considerations are discussed for two of these areas, automation and controls

  2. Nanoscale control of energy and matter: challenges and opportunities for plasma science

    International Nuclear Information System (INIS)

    Ostrikov, Kostya

    2013-01-01

    Multidisciplinary challenges and opportunities in the ultimate ability to achieve nanoscale control of energy and matter are discussed using an example of the Plasma Nanoscience. This is an emerging multidisciplinary research field at the cutting edge of a large number of disciplines including but not limited to physics and chemistry of plasmas and gas discharges, materials science, surface science, nanoscience and nanotechnology, solid state physics, space physics and astrophysics, photonics, optics, plasmonics, spintronics, quantum information, physical chemistry, biomedical sciences and related engineering subjects. The origin, progress and future perspectives of this research field driven by the global scientific and societal challenges, is examined. The future potential of the Plasma Nanoscience to remain as a highly topical area in the global research and technological agenda in the Age of Fundamental-Level Control for a Sustainable Future is assessed using a framework of the five Grand Challenges for Basic Energy Sciences recently mapped by the US Department of Energy. It is concluded that the ongoing research is very relevant and is expected to substantially expand to competitively contribute to the solution of all of these Grand Challenges. The approach to control energy and matter at nano- and subnanoscales is based on identifying the prevailing carriers and transfer mechanisms of the energy and matter at the spatial and temporal scales that are most relevant to any particular nanofabrication process. Strong accent is made on the competitive edge of the plasma-based nanotechnology in applications related to the major socio-economic issues (energy, food, water, health and environment) that are crucial for a sustainable development of humankind. Several important emerging topics, opportunities and multidisciplinary synergies for the Plasma Nanoscience are highlighted. The main nanosafety issues are also discussed and the environment- and human health

  3. Optimal control of a high-frequency class-D amplifier

    DEFF Research Database (Denmark)

    Dahl, Nicolai J.; Iversen, Niels Elkjær; Knott, Arnold

    2018-01-01

    Control loops have been used with switch-mode audio amplifiers to improve the sound quality of the amplifier. Because these amplifiers use a high-frequency modulation, precautions in the controller design must be taken. Further, the quality factor of the output filter can have a great impact...... on the controller's capabilities to suppress noise and track the audio signal. In this paper design methods for modern control are presented. The control method proves to easily overcome the challenge of designing a good performing controller when the output filter has a high quality factor. The results show...... that the controller is able to produce a clear improvement in the Total Harmonic Distortion with up to a 30 times improvement compared to open-loop with a clear reduction in the noise. This places the audio quality on pair with current solutions....

  4. OBESITY: CHALLENGES TO VENTILATORY CONTROL DURING EXERCISE A BRIEF REVIEW

    Science.gov (United States)

    Babb, Tony G.

    2013-01-01

    Obesity is a national health issue in the US. Among the many physiological changes induced by obesity, it also presents a unique challenge to ventilatory control during exercise due to increased metabolic demand of moving larger limbs, increased work of breathing due to extra weight on the chest wall, and changes in breathing mechanics. These challenges to ventilatory control in obesity can be inconspicuous or overt among obese adults but for the most part adaptation of ventilatory control during exercise in obesity appears remarkably unnoticed in the majority of obese people. In this brief review, the changes to ventilatory control required for maintaining normal ventilation during exercise will be examined, especially the interaction between respiratory neural drive and ventilation. Also, gaps in our current knowledge will be discussed. PMID:23707540

  5. Multivariable Techniques for High-Speed Research Flight Control Systems

    Science.gov (United States)

    Newman, Brett A.

    1999-01-01

    This report describes the activities and findings conducted under contract with NASA Langley Research Center. Subject matter is the investigation of suitable multivariable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Design and analysis techniques considered in this body of work are both conventional-based and contemporary-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include: (1) control architectures based on aft tail only are not well suited for highly flexible, high-speed vehicles, (2) theoretical underpinnings of the Wykes structural mode control logic is based on several assumptions concerning vehicle dynamic characteristics, and if not satisfied, the control logic can break down leading to mode destabilization, (3) two-loop control architectures that utilize small forward vanes with the aft tail provide highly attractive and feasible solutions to the longitudinal axis control challenges, and (4) closed-loop simulation sizing analyses indicate the baseline vane model utilized in this report is most likely oversized for normal loading conditions.

  6. Obesity: challenges to ventilatory control during exercise--a brief review.

    Science.gov (United States)

    Babb, Tony G

    2013-11-01

    Obesity is a national health issue in the US. Among the many physiological changes induced by obesity, it also presents a unique challenge to ventilatory control during exercise due to increased metabolic demand of moving larger limbs, increased work of breathing due to extra weight on the chest wall, and changes in breathing mechanics. These challenges to ventilatory control in obesity can be inconspicuous or overt among obese adults but for the most part adaptation of ventilatory control during exercise in obesity appears remarkably unnoticed in the majority of obese people. In this brief review, the changes to ventilatory control required for maintaining normal ventilation during exercise will be examined, especially the interaction between respiratory neural drive and ventilation. Also, gaps in our current knowledge will be discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Double-blind, placebo-controlled food challenge with apple

    DEFF Research Database (Denmark)

    Skamstrup Hansen, K; Vestergaard, H; Stahl Skov, P

    2001-01-01

    The aim of the study was to develop and evaluate different methods of double-blind, placebo-controlled food challenge (DBPCFC) with apple. Three different DBPCFC models were evaluated: fresh apple juice, freshly grated apple, and freeze-dried apple powder. All challenges were performed outside...... frequency of reactions to placebo, probably due to the ingredients used for blinding. The sensitivity of the models with freshly grated apple and freeze-dried apple powder was 0.74/0.60. An increase in sensitivity is desirable. The freeze-dried apple powder proved to be useful for SPT, HR, and oral...

  8. Double-blind, placebo controlled food challenge with apple

    DEFF Research Database (Denmark)

    Hansen, K.S.; Vestergaard, H.S.; Skov, P.S.

    2001-01-01

    The aim of the study was to develop and evaluate different methods of double-blind, placebo-controlled food challenge (DBPCFC) with apple. Three different DBPCFC models were evaluated: fresh apple juice, freshly grated apple, and freeze-dried apple powder. All challenges were performed outside...... the pollen season and took place from 1997 to 1999. The freeze-dried apple material was characterized by means of leukocyte histamine release (HR), skin prick test (SPT), and immunoblotting experiments. The study population consisted of birch pollen-allergic patients with a history of rhinitis in the birch......-pollen season and positive specific IgE to birch. For comparison of the DBPCFC models, 65 patients with a positive open oral challenge with apple were selected. In the characterization of the freeze-dried apple material, 46 birch pollen-allergic patients were included. The IgE reactivity to apple was evaluated...

  9. Nanomaterials for membrane fouling control: accomplishments and challenges.

    Science.gov (United States)

    Yang, Qian; Mi, Baoxia

    2013-11-01

    We report a review of recent research efforts on incorporating nanomaterials-including metal/metal oxide nanoparticles, carbon-based nanomaterials, and polymeric nanomaterials-into/onto membranes to improve membrane antifouling properties in biomedical or potentially medical-related applications. In general, nanomaterials can be incorporated into/onto a membrane by blending them into membrane fabricating materials or by attaching them to membrane surfaces via physical or chemical approaches. Overall, the fascinating, multifaceted properties (eg, high hydrophilicity, superparamagnetic properties, antibacterial properties, amenable functionality, strong hydration capability) of nanomaterials provide numerous novel strategies and unprecedented opportunities to fully mitigate membrane fouling. However, there are still challenges in achieving a broader adoption of nanomaterials in the membrane processes used for biomedical applications. Most of these challenges arise from the concerns over their long-term antifouling performance, hemocompatibility, and toxicity toward humans. Therefore, rigorous investigation is still needed before the adoption of some of these nanomaterials in biomedical applications, especially for those nanomaterials proposed to be used in the human body or in contact with living tissue/body fluids for a long period of time. Nevertheless, it is reasonable to predict that the service lifetime of membrane-based biomedical devices and implants will be prolonged significantly with the adoption of appropriate fouling control strategies. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  10. Challenges of particle flow reconstruction in the CMS High-Granularity Calorimeter at the High-Luminosity LHC

    CERN Document Server

    Chlebana, Frank

    2016-01-01

    The challenges of the High-Luminosity LHC (HL-LHC) are driven by the large number of overlapping proton-proton collisions (pileup) in each bunch-crossing and the extreme radiation dose to detectors positioned at high pseudorapidity. To overcome this challenge CMS is designing and implementing an endcap electromagnetic+hadronic sampling calorimeter employing silicon pad devices in the electromagnetic and front hadronic sections, comprising over 6 million channels, and highly-segmented plastic scintillators in the rear part of the hadronic section. This High-Granularity Calorimeter (HGCAL) will be the first of its kind used in a colliding beam experiment. Clustering deposits of energy over many cells and layers is a complex and challenging computational task, particularly in the high-pileup and high-event-rate environment of HL-LHC. These challenges and their solutions will be discussed in detail, as well as their implementation in the HGCAL offline reconstruction. Baseline detector performance results will be ...

  11. Highly-Integrated Hydraulic Smart Actuators and Smart Manifolds for High-Bandwidth Force Control

    Directory of Open Access Journals (Sweden)

    Victor Barasuol

    2018-06-01

    Full Text Available Hydraulic actuation is the most widely used alternative to electric motors for legged robots and manipulators. It is often selected for its high power density, robustness and high-bandwidth control performance that allows the implementation of force/impedance control. Force control is crucial for robots that are in contact with the environment, since it enables the implementation of active impedance and whole body control that can lead to a better performance in known and unknown environments. This paper presents the hydraulic Integrated Smart Actuator (ISA developed by Moog in collaboration with IIT, as well as smart manifolds for rotary hydraulic actuators. The ISA consists of an additive-manufactured body containing a hydraulic cylinder, servo valve, pressure/position/load/temperature sensing, overload protection and electronics for control and communication. The ISA v2 and ISA v5 have been specifically designed to fit into the legs of IIT’s hydraulic quadruped robots HyQ and HyQ-REAL, respectively. The key features of these components tackle 3 of today’s main challenges of hydraulic actuation for legged robots through: (1 built-in controllers running inside integrated electronics for high-performance control, (2 low-leakage servo valves for reduced energy losses, and (3 compactness thanks to metal additive manufacturing. The main contributions of this paper are the derivation of the representative dynamic models of these highly integrated hydraulic servo actuators, a control architecture that allows for high-bandwidth force control and their experimental validation with application-specific trajectories and tests. We believe that this is the first work that presents additive-manufactured, highly integrated hydraulic smart actuators for robotics.

  12. Technological Challenges for High-Brightness Photo-Injectors

    CERN Multimedia

    Suberlucq, Guy

    2004-01-01

    Many applications, from linear colliders to free-electron lasers, passing through light sources and many other electron sources, require high brightness electron beams, usually produced by photo-injectors. Because certain parameters of these applications differ by several orders of magnitude, various solutions were implemented for the design and construction of the three main parts of the photo-injectors: lasers, photocathodes and guns. This paper summarizes the different requirements, how they lead to technological challenges and how R&D programs try to overcome these challenges. Some examples of state-of-the-art parts are presented.

  13. Investigation of high-alpha lateral-directional control power requirements for high-performance aircraft

    Science.gov (United States)

    Foster, John V.; Ross, Holly M.; Ashley, Patrick A.

    1993-01-01

    Designers of the next-generation fighter and attack airplanes are faced with the requirements of good high angle-of-attack maneuverability as well as efficient high speed cruise capability with low radar cross section (RCS) characteristics. As a result, they are challenged with the task of making critical design trades to achieve the desired levels of maneuverability and performance. This task has highlighted the need for comprehensive, flight-validated lateral-directional control power design guidelines for high angles of attack. A joint NASA/U.S. Navy study has been initiated to address this need and to investigate the complex flight dynamics characteristics and controls requirements for high angle-of-attack lateral-directional maneuvering. A multi-year research program is underway which includes groundbased piloted simulation and flight validation. This paper will give a status update of this program that will include a program overview, description of test methodology and preliminary results.

  14. Ethical challenges related to elder care. High level decision-makers' experiences

    Directory of Open Access Journals (Sweden)

    Kihlgren Mona

    2007-04-01

    Full Text Available Abstract Background Few empirical studies have been found that explore ethical challenges among persons in high public positions that are responsible for elder care. The aim of this paper was to illuminate the meaning of being in ethically difficult situations related to elder care as experienced by high level decision-makers. Methods A phenomenological-hermeneutic method was used to analyse the eighteen interviews conducted with political and civil servant high level decision-makers at the municipality and county council level from two counties in Sweden. The participants worked at a planning and control as well as executive level and had both budget and quality of elder care responsibilities. Results Both ethical dilemmas and the meaning of being in ethically difficult situations related to elder care were revealed. No differences were seen between the politicians and the civil servants. The ethical dilemmas mostly concerned dealings with extensive care needs and working with a limited budget. The dilemmas were associated with a lack of good care and a lack of agreement concerning care such as vulnerable patients in inappropriate care settings, weaknesses in medical support, dissimilar focuses between the caring systems, justness in the distribution of care and deficient information. Being in ethically difficult situations was challenging. Associated with them were experiences of being exposed, having to be strategic and living with feelings such as aloneness and loneliness, uncertainty, lack of confirmation, the risk of being threatened or becoming a scapegoat and difficult decision avoidance. Conclusion Our paper provides further insight into the ethical dilemmas and ethical challenges met by high level decision-makers', which is important since the overall responsibility for elder care that is also ethically defensible rests with them. They have power and their decisions affect many stakeholders in elder care. Our results can be used to

  15. Ethical challenges related to elder care. High level decision-makers' experiences.

    Science.gov (United States)

    Mamhidir, Anna-Greta; Kihlgren, Mona; Sorlie, Venke

    2007-04-10

    Few empirical studies have been found that explore ethical challenges among persons in high public positions that are responsible for elder care. The aim of this paper was to illuminate the meaning of being in ethically difficult situations related to elder care as experienced by high level decision-makers. A phenomenological-hermeneutic method was used to analyse the eighteen interviews conducted with political and civil servant high level decision-makers at the municipality and county council level from two counties in Sweden. The participants worked at a planning and control as well as executive level and had both budget and quality of elder care responsibilities. Both ethical dilemmas and the meaning of being in ethically difficult situations related to elder care were revealed. No differences were seen between the politicians and the civil servants. The ethical dilemmas mostly concerned dealings with extensive care needs and working with a limited budget. The dilemmas were associated with a lack of good care and a lack of agreement concerning care such as vulnerable patients in inappropriate care settings, weaknesses in medical support, dissimilar focuses between the caring systems, justness in the distribution of care and deficient information. Being in ethically difficult situations was challenging. Associated with them were experiences of being exposed, having to be strategic and living with feelings such as aloneness and loneliness, uncertainty, lack of confirmation, the risk of being threatened or becoming a scapegoat and difficult decision avoidance. Our paper provides further insight into the ethical dilemmas and ethical challenges met by high level decision-makers', which is important since the overall responsibility for elder care that is also ethically defensible rests with them. They have power and their decisions affect many stakeholders in elder care. Our results can be used to stimulate discussions between high level decision-makers and health

  16. Technology Transfer Challenges for High-Assurance Software Engineering Tools

    Science.gov (United States)

    Koga, Dennis (Technical Monitor); Penix, John; Markosian, Lawrence Z.

    2003-01-01

    In this paper, we describe our experience with the challenges thar we are currently facing in our effort to develop advanced software verification and validation tools. We categorize these challenges into several areas: cost benefits modeling, tool usability, customer application domain, and organizational issues. We provide examples of challenges in each area and identrfj, open research issues in areas which limit our ability to transfer high-assurance software engineering tools into practice.

  17. New validated recipes for double-blind placebo-controlled low-dose food challenges.

    Science.gov (United States)

    Winberg, Anna; Nordström, Lisbeth; Strinnholm, Åsa; Nylander, Annica; Jonsäll, Anette; Rönmark, Eva; West, Christina E

    2013-05-01

    Double-blind placebo-controlled food challenges are considered the most reliable method to diagnose or rule out food allergy. Despite this, there are few validated challenge recipes available. The present study aimed to validate new recipes for low-dose double-blind placebo-controlled food challenges in school children, by investigating whether there were any sensory differences between the active materials containing cow's milk, hen's egg, soy, wheat or cod, and the placebo materials. The challenge materials contained the same hypoallergenic amino acid-based product, with or without added food allergens. The test panels consisted of 275 school children, aged 8-10 and 14-15 yr, respectively, from five Swedish schools. Each participant tested at least one recipe. Standardized blinded triangle tests were performed to investigate whether any sensory differences could be detected between the active and placebo materials. In our final recipes, no significant differences could be detected between the active and placebo materials for any challenge food (p > 0.05). These results remained after stratification for age and gender. The taste of challenge materials was acceptable, and no unfavourable side effects related to test materials were observed. In summary, these new validated recipes for low-dose double-blinded food challenges contain common allergenic foods in childhood; cow's milk, hen's egg, soy, wheat and cod. All test materials contain the same liquid vehicle, which facilitates preparation and dosing. Our validated recipes increase the range of available recipes, and as they are easily prepared and dosed, they may facilitate the use of double-blind placebo-controlled food challenges in daily clinical practice. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  18. Development and validation of challenge materials for double-blind, placebo-controlled food challenges in children

    NARCIS (Netherlands)

    Vlieg-Boerstra, BJ; Bijleveld, CMA; van der Heide, S; Beusekamp, BJ; Wolt-Plompen, SAA; Kukler, J; Brinkman, J; Duiverman, EJ; Dubois, AEJ

    Background: The use of double-blind, placebo-controlled food challenges (DBPCFCs) is considered the gold standard for the diagnosis of food allergy. Despite this, materials and methods used in DBPCFCs have not been standardized. Objective: The purpose of this study was to develop and validate

  19. High-End Computing Challenges in Aerospace Design and Engineering

    Science.gov (United States)

    Bailey, F. Ronald

    2004-01-01

    High-End Computing (HEC) has had significant impact on aerospace design and engineering and is poised to make even more in the future. In this paper we describe four aerospace design and engineering challenges: Digital Flight, Launch Simulation, Rocket Fuel System and Digital Astronaut. The paper discusses modeling capabilities needed for each challenge and presents projections of future near and far-term HEC computing requirements. NASA's HEC Project Columbia is described and programming strategies presented that are necessary to achieve high real performance.

  20. Implementation Challenges for Multivariable Control: What You Did Not Learn in School

    Science.gov (United States)

    Garg, Sanjay

    2008-01-01

    Multivariable control allows controller designs that can provide decoupled command tracking and robust performance in the presence of modeling uncertainties. Although the last two decades have seen extensive development of multivariable control theory and example applications to complex systems in software/hardware simulations, there are no production flying systems aircraft or spacecraft, that use multivariable control. This is because of the tremendous challenges associated with implementation of such multivariable control designs. Unfortunately, the curriculum in schools does not provide sufficient time to be able to provide an exposure to the students in such implementation challenges. The objective of this paper is to share the lessons learned by a practitioner of multivariable control in the process of applying some of the modern control theory to the Integrated Flight Propulsion Control (IFPC) design for an advanced Short Take-Off Vertical Landing (STOVL) aircraft simulation.

  1. Achievements in and Challenges of Tuberculosis Control in South Korea.

    Science.gov (United States)

    Kim, Ji Han; Yim, Jae-Joon

    2015-11-01

    After the Korean War (1950-1953), nearly 6.5% of South Korea's population had active tuberculosis (TB). In response, South Korea implemented the National Tuberculosis Program in 1962. From 1965 to 1995, the prevalence of bacteriologically confirmed pulmonary TB in South Korea decreased from 940 to 219 cases per 100,000 population. Astounding economic growth might have contributed to this result; however, TB incidence in South Korea remains the highest among high-income countries. The rate of decrease in TB incidence seems to have slowed over the past 15 years. A demographic shift toward an older population, many of whom have latent TB and various concurrent conditions, is challenging TB control efforts in South Korea. The increasing number of immigrants also plays a part in the prolonged battle against TB. A historical review of TB in South Korea provides an opportunity to understand national TB control efforts that are applicable to other parts of the world.

  2. Maternal sensitivity and latency to positive emotion following challenge: pathways through effortful control.

    Science.gov (United States)

    Conway, Anne; McDonough, Susan C; Mackenzie, Michael; Miller, Alison; Dayton, Carolyn; Rosenblum, Katherine; Muzik, Maria; Sameroff, Arnold

    2014-01-01

    The ability to self-generate positive emotions is an important component of emotion regulation. In this study, we focus on children's latency to express positive emotions following challenging situations and assess whether this ability operates through early maternal sensitivity and children's effortful control. Longitudinal relations between maternal sensitivity, infant negative affect, effortful control, and latency to positive emotion following challenge were examined in 156 children who were 33 months of age. Structural equation models supported the hypothesis that maternal sensitivity during infancy predicted better effortful control and, in turn, shorter latencies to positive emotions following challenge at 33 months. Directions for future research are discussed. © 2014 Michigan Association for Infant Mental Health.

  3. Tobacco Control Policies in Vietnam: Review on MPOWER Implementation Progress and Challenges.

    Science.gov (United States)

    Minh, Hoang Van; Ngan, Tran Thu; Mai, Vu Quynh; My, Nguyen Thi Tuyet; Chung, Le Hong; Kien, Vu Duy; Anh, Tran Tuan; Ngoc, Nguyen Bao; Giap, Vu Van; Cuong, Nguyen Manh; Manh, Pham Duc; Giang, Kim Bao

    2016-01-01

    In Vietnam, the WHO Framework Convention on Tobacco Control (WHO FCTC) took effect in March 2005 while MPOWER has been implemented since 2008. This paper describes the progress and challenges of implementation of the MPOWER package in Vietnam. We can report that, in term of monitoring, Vietnam is very active in the Global Tobacco Surveillance System, completing two rounds of the Global Adult Tobacco Survey (GATS) and three rounds of the Global Youth Tobacco Survey (GYTS). To protect people from tobacco smoke, Vietnam has issued and enforced a law requiring comprehensive smoking bans at workplaces and public places since 2013. Tobacco advertising and promotion are also prohibited with the exception of points of sale displays of tobacco products. Violations come in the form of promotion girls, corporate social responsibility activities from tobacco manufacturers and packages displayed by retail vendors. Vietnam is one of the 77 countries that require pictorial health warnings to be printed on cigarette packages to warn about the danger of tobacco and the warnings have been implemented effectively. Cigarette tax is 70% of factory price which is equal to less than 45% of retail price and much lower than the recommendation of WHO. However, Vietnam is one of the very few countries that require manufacturers and importers to make "compulsory contributions" at 1-2% of the factory price of cigarettes sold in Vietnam for the establishment of a Tobacco Control Fund (TCF). The TCF is being operated well. In 2015, 67 units of 63 provinces/cities, 22 ministries and political-social organizations and 6 hospitals received funding from TCF to implement a wide range of tobacco control activities. Cessation services have been starting with a a toll-free quit-line but need to be further strengthened. In conclusion, Vietnam has constantly put efforts into the tobacco control field with high commitment from the government, scientists and activists. Though several remarkable achievements

  4. Challenges of Technology, Social Media, and Information Control

    Science.gov (United States)

    Flaherty, Bill

    2013-01-01

    Today's youth must deal with friend management 24 hours a day, seven days a week, through smartphones and such social networking sites as Facebook. Technology in the classroom can be valuable, but not without challenges. The key is well-thought-out policies. While school districts can't completely control how students use their…

  5. Advanced motion control for next-generation precision mechatronics: Challenges for control, identification, and learning

    NARCIS (Netherlands)

    Oomen, Tom

    2017-01-01

    Manufacturing equipment and scientific instruments, including wafer scanners, printers, microscopes, and medical imaging scanners, require accurate and fast motions. Increasing requirements necessitate enhanced control performance. The aim of this paper is to identify several challenges for advanced

  6. Future Accelerator Challenges in Support of High-Energy Physics

    International Nuclear Information System (INIS)

    Zisman, Michael S.; Zisman, M.S.

    2008-01-01

    Historically, progress in high-energy physics has largely been determined by development of more capable particle accelerators. This trend continues today with the imminent commissioning of the Large Hadron Collider at CERN, and the worldwide development effort toward the International Linear Collider. Looking ahead, there are two scientific areas ripe for further exploration--the energy frontier and the precision frontier. To explore the energy frontier, two approaches toward multi-TeV beams are being studied, an electron-positron linear collider based on a novel two-beam powering system (CLIC), and a Muon Collider. Work on the precision frontier involves accelerators with very high intensity, including a Super-BFactory and a muon-based Neutrino Factory. Without question, one of the most promising approaches is the development of muon-beam accelerators. Such machines have very high scientific potential, and would substantially advance the state-of-the-art in accelerator design. The challenges of the new generation of accelerators, and how these can be accommodated in the accelerator design, are described. To reap their scientific benefits, all of these frontier accelerators will require sophisticated instrumentation to characterize the beam and control it with unprecedented precision

  7. Future Accelerator Challenges in Support of High-Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Zisman, Michael S.; Zisman, M.S.

    2008-05-03

    Historically, progress in high-energy physics has largely been determined by development of more capable particle accelerators. This trend continues today with the imminent commissioning of the Large Hadron Collider at CERN, and the worldwide development effort toward the International Linear Collider. Looking ahead, there are two scientific areas ripe for further exploration--the energy frontier and the precision frontier. To explore the energy frontier, two approaches toward multi-TeV beams are being studied, an electron-positron linear collider based on a novel two-beam powering system (CLIC), and a Muon Collider. Work on the precision frontier involves accelerators with very high intensity, including a Super-BFactory and a muon-based Neutrino Factory. Without question, one of the most promising approaches is the development of muon-beam accelerators. Such machines have very high scientific potential, and would substantially advance the state-of-the-art in accelerator design. The challenges of the new generation of accelerators, and how these can be accommodated in the accelerator design, are described. To reap their scientific benefits, all of these frontier accelerators will require sophisticated instrumentation to characterize the beam and control it with unprecedented precision.

  8. Challenges of implementing economic model predictive control strategy for buildings interacting with smart energy systems

    DEFF Research Database (Denmark)

    Zong, Yi; Böning, Georg Martin; Santos, Rui Mirra

    2016-01-01

    ) strategy for energy management in smart buildings, which can act as active users interacting with smart energy systems. The challenges encountered during the implementation of EMPC for active demand side management are investigated in detail in this paper. A pilot testing study shows energy savings......When there is a high penetration of renewables in the energy system, it requires proactive control of large numbers of distributed demand response resources to maintain the system’s reliability and improve its operational economics. This paper presents the Economic Model Predictive Control (EMPC...

  9. Healthcare workers' challenges in the implementation of tuberculosis infection prevention and control measures in Mozambique.

    Science.gov (United States)

    Brouwer, Miranda; Coelho, Eliana; Mosse, Carla das Dores; Brondi, Luciana; Winterton, Laura; van Leth, Frank

    2014-01-01

    Healthcare Workers (HCWs) have a higher frequency of TB exposure than the general population and have therefore an occupational TB risk that infection prevention and control (IPC) measures aim to reduce. HCWs are crucial in the implementation of these measures. The objective of the study was to investigate Mozambican HCWs' perceptions of their occupational TB risk and the measures they report using to reduce this risk. In addition, we explored the challenges HCWs encounter while using these TBIPC measures. Focus group discussion. Analysis according content method. Four categories of HCWs: auxiliary workers, medical (doctors and clinical officers), nurses and TB program staff. HCWs are aware of their occupational TB risk and use various measures to reduce their risk of infection. HCWs find it challenging to employ measures that minimize such risks and a lack of clear guidelines contributes to these challenges. HCWs' and patient behavior further complicate the use of TBIPC measures. HCWs in Mozambique perceive a high occupational risk of TB infection. They report several challenges using measures to reduce this risk such as shortage of material, lack of clear guidelines, insufficient motivation and inadequate training. Robust training with motivational approaches, alongside supervision and support for HCWs could improve implementation of TBIPC measures. Healthcare management should address the areas for improvement that are beyond the individual HCW's control.

  10. Validation and acceptability of double-blind, placebo-controlled food challenges in children

    NARCIS (Netherlands)

    Venter, Carina; Maslin, Kate; Patil, Veeresh; Grundy, Jane; Glasbey, Gillian; Raza, Abid; Vlieg-Boerstra, Berber; Dean, Taraneh

    2016-01-01

    The Double Blind Placebo Controlled Food Challenge (DBPCFC) is considered the gold standard for food allergy diagnosis (1, 2). It is recommended that active and placebo challenge foods for DBPCFCs are sufficiently blinded in terms of smell, flavour and texture. Difficulties arise with children

  11. Challenges of Control in Functional Organization Structures: Example of Outsourcing Sector

    Directory of Open Access Journals (Sweden)

    Agnieszka Maciejczyk

    2016-07-01

    Full Text Available Effective control of an organization is strictly connected with its organization structure. When a company decides to outsource a part of its operations, a new structure is applied. Also, the system of control should be reviewed and adjusted to the new model of business in order to be effective. Usually, the outsourcing companies apply functional organization structure which is the most common way of grouping business activities. The goal of the paper was to point challenges and aspects which should be taken into consideration in order to adapt control systems to new organization structures in case of Business Process Outsourcing and Shared Service Centers. The research was based on literature studies as well as empirical analysis of selected companies from business service centers sector. The key findings of the study suggest that the mechanisms of control differ in Business Process Outsourcing and Shared Service organizations although both base on building trust and relationship. The main challenges of adapting the control system to new conditions comprise people and process related factors such as: knowledge management, control split and owners, new processes flows, virtual teams. Building control system is a process which foundation is a new organization structure.

  12. Controls for microgrids with storage: Review, challenges, and research needs

    Energy Technology Data Exchange (ETDEWEB)

    Zamora, Ramon [Department of Electrical and Computer Engineering, Mississippi State University, P O Box 9571, Mississippi State, MS 39762 (United States); Department of Electrical Engineering, Syiah Kuala University, Banda Aceh 23111 (Indonesia); Srivastava, Anurag K. [Department of Electrical and Computer Engineering, Mississippi State University, P O Box 9571, Mississippi State, MS 39762 (United States)

    2010-09-15

    The interest on microgrid has increased significantly triggered by the increasing demand of reliable, secure, efficient, clean, and sustainable electricity. More research and implementation of microgrid will be conducted in order to improve the maturity of microgrid technology. Among different aspects of microgrid, this paper focuses on controls of microgrid with energy storage. A comprehensive review on current control technology is given with a discussion on challenges of microgrid controls. Basic simulation results are also presented to enhance and support the analysis. Finally, research needs and roadmap for microgrid control are also described. (author)

  13. Control Engineering, System Theory and Mathematics: The Teacher's Challenge

    Science.gov (United States)

    Zenger, K.

    2007-01-01

    The principles, difficulties and challenges in control education are discussed and compared to the similar problems in the teaching of mathematics and systems science in general. The difficulties of today's students to appreciate the classical teaching of engineering disciplines, which are based on rigorous and scientifically sound grounds, are…

  14. Tritium control and capture in salt-cooled fission and fusion reactors: Status, challenges, and path forward

    International Nuclear Information System (INIS)

    Forsberg, Charles W.; Lam, Stephen; Carpenter, David M.; Whyte, Dennis G.; Scarlat, Raluca

    2017-01-01

    Three advanced nuclear power systems use liquid salt coolants that generate tritium and thus face the common challenges of containing and capturing tritium to prevent its release to the environment. The Fluoride-salt-cooled High-temperature Reactor (FHR) uses clean fluoride salt coolants and the same graphite-matrix coated-particle fuel as high-temperature gas-cooled reactors. Molten salt reactors (MSRs) dissolve the fuel in a fluoride or chloride salt with release of fission product tritium into the salt. In most FHR and MSR systems, the base-line salts contain lithium where isotopically separated "7Li is proposed to minimize tritium production from neutron interactions with the salt. The Chinese Academy of Science plans to start operation of a 2-MWt molten salt test reactor by 2020. For high-magnetic-field fusion machines, the use of lithium enriched in "6Li is proposed to maximize tritium generation the fuel for a fusion machine. Advances in superconductors that enable higher power densities may require the use of molten lithium salts for fusion blankets and as coolants. Recent technical advances in these three reactor classes have resulted in increased government and private interest and the beginning of a coordinated effort to address the tritium control challenges in 700 °C liquid salt systems. We describe characteristics of salt-cooled fission and fusion machines, the basis for growing interest in these technologies, tritium generation in molten salts, the environment for tritium capture, models for high-temperature tritium transport in salt systems, alternative strategies for tritium control, and ongoing experimental work. Several methods to control tritium appear viable. Finally, limited experimental data is the primary constraint for designing efficient cost-effective methods of tritium control.

  15. Investigation of Inner Loop Flight Control Strategies for High-Speed Research

    Science.gov (United States)

    Newman, Brett; Kassem, Ayman

    1999-01-01

    This report describes the activities and findings conducted under contract NAS1-19858 with NASA Langley Research Center. Subject matter is the investigation of suitable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Techniques considered in this body of work are primarily conventional-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include 1) current aeroelastic vehicle modeling procedures require further emphasis and refinement, 2) traditional and nontraditional inner loop flight control strategies employing a single feedback loop do not appear sufficient for highly flexible HSCT class vehicles, 3) inner loop flight control systems will, in all likelihood, require multiple interacting feedback loops, and 4) Ref. H HSCT configuration presents major challenges to designing acceptable closed-loop flight dynamics.

  16. Notification: FY 2018 CSB Management Challenges and Internal Control Weaknesses

    Science.gov (United States)

    December 26, 2017. The OIG is beginning work to update for fiscal year 2018 its list of proposed key management challenges and internal control weaknesses confronting the U.S. Chemical Safety and Hazard Investigation Board (CSB).

  17. Experiences in messaging middle-ware for high-level control applications

    International Nuclear Information System (INIS)

    Wanga, N.; Shasharina, S.; Matykiewicz, J.; Rooparani Pundaleeka

    2012-01-01

    Existing high-level applications in accelerator control and modeling systems leverage many different languages, tools and frameworks that do not inter-operate with one another. As a result, the accelerator control community is moving toward the proven Service-Oriented Architecture (SOA) approach to address the inter-operability challenges among heterogeneous high-level application modules. Such SOA approach enables developers to package various control subsystems and activities into 'services' with well-defined 'interfaces' and make leveraging heterogeneous high-level applications via flexible composition possible. Examples of such applications include presentation panel clients based on Control System Studio (CSS) and middle-layer applications such as model/data servers. This paper presents our experiences in developing a demonstrative high-level application environment using emerging messaging middle-ware standards. In particular, we utilize new features in EPICS v4 and other emerging standards such as Data Distribution Service (DDS) and Extensible Type Interface by the Object Management Group. We first briefly review examples we developed previously. We then present our current effort in integrating DDS into such a SOA environment for control systems. Specifically, we illustrate how we are integrating DDS into CSS and develop a Python DDS mapping. (authors)

  18. Challenges in setting up quality control in diagnostic radiology ...

    African Journals Online (AJOL)

    Journal Home > Vol 24, No 4 (2015) >. Log in or ... Quality control (QC) on diagnostic radiology equipment form part of the fundamental requirements for the ... Inadequate cooperation by facilities management, lack of QC equipment and insufficient staff form the major challenges in setting up QC in the facilities under study.

  19. Development and Application of Plasma Actuators for Active Control of High-Speed and High Reynolds Number Flows

    Science.gov (United States)

    Sammy, Mo

    2010-01-01

    Active flow control is often used to manipulate flow instabilities to achieve a desired goal (e.g. prevent separation, enhance mixing, reduce noise, etc.). Instability frequencies normally scale with flow velocity scale and inversely with flow length scale (U/l). In a laboratory setting for such flow experiments, U is high, but l is low, resulting in high instability frequency. In addition, high momentum and high background noise & turbulence in the flow necessitate high amplitude actuation. Developing a high amplitude and high frequency actuator is a major challenge. Ironically, these requirements ease up in application (but other issues arise).

  20. Burnout, social support, and coping at work among social workers, psychologists, and nurses: the role of challenge/control appraisals.

    Science.gov (United States)

    Ben-Zur, Hasida; Michael, Keren

    2007-01-01

    The purpose of this study is twofold: (1) to compare stress appraisals, coping strategies, social resources, and burnout at work between social workers, psychologists and nurses; and (2) to assess the effectiveness of appraisals and support in reducing burnout and enhancing effective coping strategies. Questionnaires containing assessments of work stress appraisals, coping strategies used to deal with problems at work, and social support at work, as well as burnout measures of exhaustion, depersonalization, and accomplishment were completed by 249 female professionals (age range 25-61). No differences were observed between the three professions on most psychological measures, except for the depersonalization outcome of burnout, which was significantly lower among psychologists than among nurses or social workers. High challenge/control appraisal of the job was directly related to all burnout outcomes, contributing to less exhaustion and depersonalization and to more personal accomplishment. The challenge/control appraisal was also negatively associated with emotion-focused coping. By comparison, the stress/load appraisal contributed to more exhaustion at work, while emotion-focused coping contributed to higher depersonalization. Social support was associated with higher challenge/control appraisal, with the latter mediating support effects on burnout. These data suggest that the perception of challenge/control in one's work may be an important factor in preventing work burnout in the three professions tested in the study.

  1. An Ultra-low Frequency Modal Testing Suspension System for High Precision Air Pressure Control

    Directory of Open Access Journals (Sweden)

    Qiaoling YUAN

    2014-05-01

    Full Text Available As a resolution for air pressure control challenges in ultra-low frequency modal testing suspension systems, an incremental PID control algorithm with dead band is applied to achieve high-precision pressure control. We also develop a set of independent hardware and software systems for high-precision pressure control solutions. Taking control system versatility, scalability, reliability, and other aspects into considerations, a two-level communication employing Ethernet and CAN bus, is adopted to complete such tasks as data exchange between the IPC, the main board and the control board ,and the pressure control. Furthermore, we build a single set of ultra-low frequency modal testing suspension system and complete pressure control experiments, which achieve the desired results and thus confirm that the high-precision pressure control subsystem is reasonable and reliable.

  2. Factors Relating to Staff Attributions of Control over Challenging Behaviour

    Science.gov (United States)

    Dilworth, Jennifer A.; Phillips, Neil; Rose, John

    2011-01-01

    Background: Previous research has suggested that severity of intellectual disability (ID) and topography of behaviour may influence staff causal attributions regarding challenging behaviour. Subsequently, these causal attributions may influence helping behaviours. This study investigated the relationship between attributions of control over…

  3. Challenges in Modelling and Control of Offshore De-oiling Hydrocyclone Systems

    DEFF Research Database (Denmark)

    Løhndorf, Petar Durdevic; Pedersen, Simon; Yang, Zhenyu

    2017-01-01

    , and alternatively this task imposes a number of key control challenges. Specifically, there is much research to be performed in the direction of dynamic modelling and control of de-oiling hydrocyclone systems. The current solutions rely heavily on empirical trial-and-error approaches. This paper gives a brief......Offshore de-oiling installations are facing an increasing challenge with regards to removing oil residuals from produced water prior to discharge into the ocean. The de-oiling of produced water is initially achieved in the primary separation processes using gravity-based multi-phase separators...... in the produced water before it can be discharged into the ocean. The popularity of hydrocyclone technology in the offshore oil and gas industry is mainly due to its rugged design and low maintenance requirements. However, to operate and control this type of system in an efficient way is far less simple...

  4. Facing the challenges of distribution systems operation with high wind power penetration

    DEFF Research Database (Denmark)

    Das, Kaushik; Altin, Müfit; Hansen, Anca Daniela

    2017-01-01

    power flow in 60kV distribution networks through controlling the ability of wind power plants (WPPs) to generate or absorb reactive power. This paper aims to understand the characteristics of a distribution network with high penetration of distributed generation. A detailed analysis of the active...... and reactive power flows in a real distribution network under different wind and load conditions based on actual measurements is performed in order to understand the correlation between the consumption, wind power production, and the network losses. Conclusive remarks are presented, briefly expressing......This paper addresses the challenges associated with the operation of a distribution system with high penetration of wind power. The paper presents some preliminary investigations of an ongoing Danish research work, which has as main objective to reduce the network losses by optimizing the reactive...

  5. Geoinformatics in Infectious Disease Control: Challenges and the ...

    African Journals Online (AJOL)

    The challenges in this wise were low level of technological development, inconsistency and inept implementation of government policies, low level of investment in the health sector, inadequate healthcare facilities, high cost of acquisition of relevant space technology, and low level of literacy. To surmount these constraints, ...

  6. Challenges on the high luminosity frontier of e+ e-

    International Nuclear Information System (INIS)

    Barletta, W.A.

    1993-05-01

    For phi factories, tau-charm factories, and B factories to meet their respective luminosity goals, the circulating currents that typify e + e - colliders must be raised an order of magnitude. At the same time the beam size at the interaction point must be decreased. The approaches to realizing these conditions include increasing the charge per bunch, increasing the number of bunches in the collider, increasing the crossing angle for rapid bunch separation, tilting the bunch with respect to the direction of motion at the interaction point (''crab-crossing''), and minimizing the β function at the interaction point. The technological challenges implied by such strategies include the development of (1) novel rf-cavity designs to suppress higher order modes and to provide large rf-voltages for longitudinal focusing, (2) a new generation of powerful feedback electronics to control multi-bunch instabilities, and (3) vacuum chambers and pumping schemes suitable for operation with very high levels of synchrotron radiation. In high current colliders the design of the interaction region poses special problems of allowing rapid beam separation and avoiding excessive scattering of background radiation into the detector

  7. Feedback controlled, reactor relevant, high-density, high-confinement scenarios at ASDEX Upgrade

    Science.gov (United States)

    Lang, P. T.; Blanken, T. C.; Dunne, M.; McDermott, R. M.; Wolfrum, E.; Bobkov, V.; Felici, F.; Fischer, R.; Janky, F.; Kallenbach, A.; Kardaun, O.; Kudlacek, O.; Mertens, V.; Mlynek, A.; Ploeckl, B.; Stober, J. K.; Treutterer, W.; Zohm, H.; ASDEX Upgrade Team

    2018-03-01

    One main programme topic at the ASDEX Upgrade all-metal-wall tokamak is development of a high-density regime with central densities at reactor grade level while retaining high-confinement properties. This required development of appropriate control techniques capable of coping with the pellet tool, a powerful means of fuelling but one which presented challenges to the control system for handling of related perturbations. Real-time density profile control was demonstrated, raising the core density well above the Greenwald density while retaining the edge density in order to avoid confinement losses. Recently, a new model-based approach was implemented that allows direct control of the central density. Investigations focussed first on the N-seeding scenario owing to its proven potential to yield confinement enhancements. Combining pellets and N seeding was found to improve the divertor buffering further and enhance the operational range accessible. For core densities up to about the Greenwald density, a clear improvement with respect to the non-seeding reference was achieved; however, at higher densities this benefit is reduced. This behaviour is attributed to recurrence of an outward shift of the edge density profile, resulting in a reduced peeling-ballooning stability. This is similar to the shift seen during strong gas puffing, which is required to prevent impurity influx in ASDEX Upgrade. First tests indicate that highly-shaped plasma configurations like the ITER base-line scenario, respond very well to pellet injection, showing efficient fuelling with no measurable impact on the edge density profile.

  8. WHO Framework Convention on Tobacco Control in China: barriers, challenges and recommendations.

    Science.gov (United States)

    Hu, Teh-Wei; Lee, Anita H; Mao, Zhengzhong

    2013-12-01

    The aim of this study was to analyze the barriers in the implementation of the Framework Convention on Tobacco Control (FCTC) in China and present recommendations on ways to address these challenges in tobacco control in China. We review the available literature on progress and explore the barriers and challenges that impede a speedier pace in the adoption of the effective tobacco control measures, and present recommendations based on in-depth knowledge of decision-making process on the implementation of FCTC in China. The pace of progress in China is too slow. China faces intractable political, structural, economic and social barriers in tobacco control, which make the whole-hearted implementation of FCTC measures a painstaking process. The authors recommend a comprehensive approach to speed up the implementation of tobacco control measures. This includes strong political leadership from the top, structural changes to the tobacco industry and government oversight of the tobacco industry, as well as advocacy and support for tobacco control from civil society at the grassroots level.

  9. Animals In Synchrotrons: Overcoming Challenges For High-Resolution, Live, Small-Animal Imaging

    International Nuclear Information System (INIS)

    Donnelley, Martin; Parsons, David; Morgan, Kaye; Siu, Karen

    2010-01-01

    Physiological studies in small animals can be complicated, but the complexity is increased dramatically when performing live-animal synchrotron X-ray imaging studies. Our group has extensive experience in high-resolution live-animal imaging at the Japanese SPring-8 synchrotron, primarily examining airways in two-dimensions. These experiments normally image an area of 1.8 mmx1.2 mm at a pixel resolution of 0.45 μm and are performed with live, intact, anaesthetized mice.There are unique challenges in this experimental setting. Importantly, experiments must be performed in an isolated imaging hutch not specifically designed for small-animal imaging. This requires equipment adapted to remotely monitor animals, maintain their anesthesia, and deliver test substances while collecting images. The horizontal synchrotron X-ray beam has a fixed location and orientation that limits experimental flexibility. The extremely high resolution makes locating anatomical regions-of-interest slow and can result in a high radiation dose, and at this level of magnification small animal movements produce motion-artifacts that can render acquired images unusable. Here we describe our experimental techniques and how we have overcome several challenges involved in performing live mouse synchrotron imaging.Experiments have tested different mouse strains, with hairless strains minimizing overlying skin and hair artifacts. Different anesthetics have also be trialed due to the limited choices available at SPring-8. Tracheal-intubation methods have been refined and controlled-ventilation is now possible using a specialized small-animal ventilator. With appropriate animal restraint and respiratory-gating, motion-artifacts have been minimized. The animal orientation (supine vs. head-high) also appears to affect animal physiology, and can alter image quality. Our techniques and image quality at SPring-8 have dramatically improved and in the near future we plan to translate this experience to the

  10. Overlay control methodology comparison: field-by-field and high-order methods

    Science.gov (United States)

    Huang, Chun-Yen; Chiu, Chui-Fu; Wu, Wen-Bin; Shih, Chiang-Lin; Huang, Chin-Chou Kevin; Huang, Healthy; Choi, DongSub; Pierson, Bill; Robinson, John C.

    2012-03-01

    Overlay control in advanced integrated circuit (IC) manufacturing is becoming one of the leading lithographic challenges in the 3x and 2x nm process nodes. Production overlay control can no longer meet the stringent emerging requirements based on linear composite wafer and field models with sampling of 10 to 20 fields and 4 to 5 sites per field, which was the industry standard for many years. Methods that have emerged include overlay metrology in many or all fields, including the high order field model method called high order control (HOC), and field by field control (FxFc) methods also called correction per exposure. The HOC and FxFc methods were initially introduced as relatively infrequent scanner qualification activities meant to supplement linear production schemes. More recently, however, it is clear that production control is also requiring intense sampling, similar high order and FxFc methods. The added control benefits of high order and FxFc overlay methods need to be balanced with the increased metrology requirements, however, without putting material at risk. Of critical importance is the proper control of edge fields, which requires intensive sampling in order to minimize signatures. In this study we compare various methods of overlay control including the performance levels that can be achieved.

  11. Smoking control: challenges and achievements

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Corrêa da Silva

    Full Text Available ABSTRACT Smoking is the most preventable and controllable health risk. Therefore, all health care professionals should give their utmost attention to and be more focused on the problem of smoking. Tobacco is a highly profitable product, because of its large-scale production and great number of consumers. Smoking control policies and treatment resources for smoking cessation have advanced in recent years, showing highly satisfactory results, particularly in Brazil. However, there is yet a long way to go before smoking can be considered a controlled disease from a public health standpoint. We can already perceive that the behavior of our society regarding smoking is changing, albeit slowly. Therefore, pulmonologists have a very promising area in which to work with their patients and the general population. We must act with greater impetus in support of health care policies and social living standards that directly contribute to improving health and quality of life. In this respect, pulmonologists can play a greater role as they get more involved in treating smokers, strengthening anti-smoking laws, and demanding health care policies related to lung diseases.

  12. Smoking control: challenges and achievements

    Science.gov (United States)

    da Silva, Luiz Carlos Corrêa; de Araújo, Alberto José; de Queiroz, Ângela Maria Dias; Sales, Maria da Penha Uchoa; Castellano, Maria Vera Cruz de Oliveira

    2016-01-01

    ABSTRACT Smoking is the most preventable and controllable health risk. Therefore, all health care professionals should give their utmost attention to and be more focused on the problem of smoking. Tobacco is a highly profitable product, because of its large-scale production and great number of consumers. Smoking control policies and treatment resources for smoking cessation have advanced in recent years, showing highly satisfactory results, particularly in Brazil. However, there is yet a long way to go before smoking can be considered a controlled disease from a public health standpoint. We can already perceive that the behavior of our society regarding smoking is changing, albeit slowly. Therefore, pulmonologists have a very promising area in which to work with their patients and the general population. We must act with greater impetus in support of health care policies and social living standards that directly contribute to improving health and quality of life. In this respect, pulmonologists can play a greater role as they get more involved in treating smokers, strengthening anti-smoking laws, and demanding health care policies related to lung diseases. PMID:27832238

  13. Challenges and Opportunities for Transactive Control of Electric Vehicle Supply Equipment. A Reference Guide

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Meintz, Andrew [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-29

    This report seeks to characterize the opportunities and challenges that arise in developing a transactive control strategy for grid-EVSE integration in various use-case scenarios in a way that provides end-user, energy market, grid, and societal benefits. A detailed review provides information about EVSE integration market trends and stakeholder activities. This is followed by an exploration of value proposition for transactive control of EVSE at both the home scale and the building/campus scale. This report will serve as a reference guide for stakeholders in the grid-EVSE integration area, illustrate potential implementations, and identify a high-value research project for overcoming the barriers and unlocking the benefits of transactive controls of EVSE. While it is not intended to specify the technical details of the transactive control solution, the report contains a list of use cases describing potential applications of transactive control of EVSE, barriers to implementing these applications, and research and development (R&D) opportunities to overcome the barriers. The use cases of transactive control of EVSE are listed in Table ES1.

  14. Leprosy Elimination: Progress and Challenges in Nigeria; Kaduna State TB and Leprosy Control Programme as a Case Study.

    Science.gov (United States)

    Mustapha, Gidado; Olusegu, Obasanya Joshua; Mustapha, Sani; Clement, Adesigbin; Dahiru, Tahir; Gagere, J; Olusola, Adejumo Adeleji

    2012-01-01

    The study aims at describing the achievements and challenges of Leprosy control in Kaduna State using appropriate indicators. The study was a five year (2004-2008) retrospective review of the Leprosy records and annual reports of all the twenty three LGAs in Kaduna State. Various Leprosy indicators were calculated and presented in different graphic presentations. Focus group discussions were organised with the aim of identifying current challenges of Leprosy control in the State. There was a decline in the new Leprosy cases detected annually from 226 cases in 2004 to 140 cases in 2008. The prevalence rate ranged between 0.3-0.4 per 10,000 population within the five year period. The proportion of children among new cases dropped from 12% in 2004 to 5% in 2007 and increased to 9% in 2008. Grade 2 disability among new cases was very high (between 21%-27%) within the same period. Leprosy elimination target has been achieved in Kaduna State, but new cases with high proportion of children and WHO grade 2 disability were still been reported.

  15. Schistosoma mansoni: is acquired immunity induced by highly x-irradiated cercariae dependent on the size of the challenging dose

    International Nuclear Information System (INIS)

    Hsue, S.Y.; Hsue, H.F.; Osborne, J.W.; Johnson, S.C.

    1982-01-01

    A high degree of immunity, as shown by a 91% reduction of the number of worms recovered was found in five groups of mice that were immunized five times with highly X-irradiated cercariae and then challenged with 10, 20, 50, 100, or 500 normal Schistosoma mansoni cercariae. The results indicated that there were no significant differences in worm reduction in immunized mice challenged with different numbers of cercariae; consequently the immunity induced by this immunization method did not appear to be challenge-dose-dependent. However, the results also showed that when immunized mice were challenged with 500, 100, 50, 20, and 10 cercariae, 0, 13, 26, 56, and 68%, respectively, of the experimental animals were free of worms. Thus, the percentage of worm-negative cases increased as the number of challenge cercariae decreased. When viewed in this manner, the acquired immunity may be considered challenge-dose-dependent as well. If this method of vaccination is used for schistosomiasis control, we may anticipate that in both hypo- and hyperendemic areas, the intensity of infection and the severity of the disease will be reduced owing to a reduction in worms burdens, and in hypoendemic areas, there will be a number of worm-free cases

  16. FPGA cluster for high-performance AO real-time control system

    Science.gov (United States)

    Geng, Deli; Goodsell, Stephen J.; Basden, Alastair G.; Dipper, Nigel A.; Myers, Richard M.; Saunter, Chris D.

    2006-06-01

    Whilst the high throughput and low latency requirements for the next generation AO real-time control systems have posed a significant challenge to von Neumann architecture processor systems, the Field Programmable Gate Array (FPGA) has emerged as a long term solution with high performance on throughput and excellent predictability on latency. Moreover, FPGA devices have highly capable programmable interfacing, which lead to more highly integrated system. Nevertheless, a single FPGA is still not enough: multiple FPGA devices need to be clustered to perform the required subaperture processing and the reconstruction computation. In an AO real-time control system, the memory bandwidth is often the bottleneck of the system, simply because a vast amount of supporting data, e.g. pixel calibration maps and the reconstruction matrix, need to be accessed within a short period. The cluster, as a general computing architecture, has excellent scalability in processing throughput, memory bandwidth, memory capacity, and communication bandwidth. Problems, such as task distribution, node communication, system verification, are discussed.

  17. Development of a Single High Fat Meal Challenge to Unmask ...

    Science.gov (United States)

    Stress tests are used clinically to determine the presence of underlying disease and predict future cardiovascular risk. In previous studies, we used treadmill exercise stress in rats to unmask the priming effects of air pollution inhalation. Other day-to-day activities stress the cardiovascular system, and when modeled experimentally, may be useful in identifying latent effects of air pollution exposure. For example, a single high fat (HF) meal can cause transient vascular endothelial dysfunction and increases in LDL cholesterol, triglycerides (TG), oxidative stress, and inflammation. Given the prevalence of HF meals in western diets, the goal of this study was to develop a HF meal challenge in rats to see if air pollution primes the body for a subsequent stress-induced adverse response. Healthy male Wistar Kyoto rats were fasted for six hours and then administered a single oral gavage of isocaloric lard-based HF or low fat (LF) suspensions, or a water vehicle control. We hypothesized that rats given a HF load would elicit postprandial changes in cardiopulmonary function that were distinct from LF and vehicle controls. One to four hours after gavage, rats underwent whole body plethysmography to assess breathing patterns, cardiovascular ultrasounds, blood draws for measurements of systemic lipids and hormones and a test for sensitivity to aconitine-induced arrhythmia. HF gavage caused an increase in circulating TG relative to LF and vehicle controls and an incre

  18. High Performance Numerical Computing for High Energy Physics: A New Challenge for Big Data Science

    International Nuclear Information System (INIS)

    Pop, Florin

    2014-01-01

    Modern physics is based on both theoretical analysis and experimental validation. Complex scenarios like subatomic dimensions, high energy, and lower absolute temperature are frontiers for many theoretical models. Simulation with stable numerical methods represents an excellent instrument for high accuracy analysis, experimental validation, and visualization. High performance computing support offers possibility to make simulations at large scale, in parallel, but the volume of data generated by these experiments creates a new challenge for Big Data Science. This paper presents existing computational methods for high energy physics (HEP) analyzed from two perspectives: numerical methods and high performance computing. The computational methods presented are Monte Carlo methods and simulations of HEP processes, Markovian Monte Carlo, unfolding methods in particle physics, kernel estimation in HEP, and Random Matrix Theory used in analysis of particles spectrum. All of these methods produce data-intensive applications, which introduce new challenges and requirements for ICT systems architecture, programming paradigms, and storage capabilities.

  19. HOM frequency control of SRF cavity in high current ERLs

    Science.gov (United States)

    Xu, Chen; Ben-Zvi, Ilan

    2018-03-01

    The acceleration of high-current beam in Superconducting Radio Frequency (SRF) cavities is a challenging but essential for a variety of advanced accelerators. SRF cavities should be carefully designed to minimize the High Order Modes (HOM) power generated in the cavities by the beam current. The reduction of HOM power we demonstrate in a particular case can be quite large. This paper presents a method to systematically control the HOM resonance frequencies in the initial design phase to minimize the HOM power generation. This method is expected to be beneficial for the design of high SRF cavities addressing a variety of Energy Recovery Linac (ERL) applications.

  20. Electronic Devices for Controlling the Very High Voltage in the ALICE TPC Detector

    CERN Document Server

    Boccioli, Marco

    2007-01-01

    The Time Projection Chamber (TPC) is the core of the ALICE experiment at CERN. The TPC Very High Voltage project covers the development of the control system for the power supply that generates the 100kV necessary for the drift field in the TPC. This paper reports on the project progress, introducing the control system architecture from the electronics up to the control level. All the electronic devices will be described, highlighting their communication issues, and the challenges in integrating these devices in a PLC-based control system.

  1. Challenges for maintaining the modernization of instrumentation and control systems

    International Nuclear Information System (INIS)

    Rojas, V.

    2014-01-01

    Instrumentation and control system upgrades in nuclear power plants come with some challenges for their maintenance staff. It is important to have a long term modernization plant that derives from specific studies for each system. Training, spares, configuration control and cybersecurity are critical topics to take into account from the beginning of these projects. New system maintenance plans can require a new approach in accordance with the technology. FPGAs (Field Programmable Gate Array) appear as the alternative for the future, mainly in safety systems. (Author)

  2. Masking foods for food challenge: practical aspects of masking foods for a double-blind, placebo-controlled food challenge

    NARCIS (Netherlands)

    Huijbers, G. B.; Colen, A. A.; Jansen, J. J.; Kardinaal, A. F.; Vlieg-Boerstra, B. J.; Martens, B. P.

    1994-01-01

    In diagnosing a food allergy or food intolerance, a double-blind, placebo-controlled food challenge (DBPCFC) with the suspected food or food substance is the only method available for objective confirmation of an assumed relationship between a suspected agent and a complaint. When the use of

  3. Key scientific challenges in geological disposal of high level radioactive waste

    International Nuclear Information System (INIS)

    Wang Ju

    2007-01-01

    The geological disposal of high radioactive waste is a challenging task facing the scientific and technical world. This paper introduces the latest progress of high level radioactive disposal programs in the latest progress of high level radioactive disposal programs in the world, and discusses the following key scientific challenges: (1) precise prediction of the evolution of a repository site; (2) characteristics of deep geological environment; (3) behaviour of deep rock mass, groundwater and engineering material under coupled con-ditions (intermediate to high temperature, geostress, hydraulic, chemical, biological and radiation process, etc); (4) geo-chemical behaviour of transuranic radionuclides with low concentration and its migration with groundwater; and (5) safety assessment of disposal system. Several large-scale research projects and several hot topics related with high-level waste disposal are also introduced. (authors)

  4. The challenge of recruiting patients into a placebo-controlled surgical trial

    DEFF Research Database (Denmark)

    Hare, Kristoffer B; Lohmander, L Stefan; Roos, Ewa M.

    2014-01-01

    BACKGROUND: Randomized placebo-controlled trials represent the gold standard in evaluating healthcare interventions but are rarely performed within orthopedics. Ethical concerns or well-known challenges in recruiting patients for surgical trials in general have been expressed and adding a placebo...

  5. Technical Challenges in the Application and Licensing of Digital Instrumentation and Control Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    2015-01-01

    With the modernization of existing analogue instrumentation and control (I&C) systems in nuclear power plants through digital I&C technology, and the implementation of digital I&C systems in new plants, the industry is faced with significant challenges. These challenges appear in the form of difficulties in managing the necessarily incremental transition, highly integrated (and interdependent) architectures, the flexible configurability enabled by digital technology, and uncertainty and inconsistency in licensing digital I&C systems and equipment in the different Member States. This publication discusses 17 major issues that utilities, developers, suppliers and regulatory stakeholders need to consider, so that the industry can capture and benefit from shared experience, recent technological developments, and emerging best practices

  6. No matrix effect in double-blind, placebo-controlled egg challenges in egg allergic children

    NARCIS (Netherlands)

    Libbers, L.; Flokstra-de Blok, B. M. J.; Vlieg-Boerstra, B. J.; van der Heide, S.; van der Meulen, G. N.; Kukler, J.; Kerkhof, M.; Dubois, A. E. J.

    Background Diagnostic and accidental food allergic reactions may be modified by the matrix containing the allergenic food. Previous studies of double-blind, placebo-controlled food challenges (DBPCFCs) with peanut found an effect of the fat content of the challenge matrix on the severity of the

  7. NASA Engineering Design Challenges: Environmental Control and Life Support Systems. Water Filtration Challenge. EG-2008-09-134-MSFC

    Science.gov (United States)

    Schneider, Twila, Ed.

    2010-01-01

    This educator guide is organized into seven chapters: (1) Overview; (2) The Design Challenge; (3) Connections to National Curriculum Standards; (4) Preparing to Teach; (5) Classroom Sessions; (6) Opportunities for Extension; and (7) Teacher Resources. Chapter 1 provides information about Environmental Control and Life Support Systems used on NASA…

  8. CHALLENGES IN SETTING UP QUALITY CONTROL IN DIAGNOSTIC RADIOLOGY FACILITIES IN NIGERIA.

    Science.gov (United States)

    Inyang, S O; Egbe, N O; Ekpo, E

    2015-01-01

    The Nigerian Nuclear Regulatory Authority (NNRA) was established to regulate and control the use of radioactive and radiation emitting sources in Nigeria. Quality control (QC) on diagnostic radiology equipment form part of the fundamental requirements for the authorization of diagnostic radiology facilities in the Country. Some quality control tests (output, exposure linearity and reproducibility) were measured on the x-ray machines in the facilities that took part in the study. Questionnaire was developed to evaluate the frequencies at which QC tests were conducted in the facilities and the challenges in setting up QC. Results show great variation in the values of the QC parameters measured. Inadequate cooperation by facilities management, lack of QC equipment and insufficient staff form the major challenges in setting up QC in the facilities under study. The responses on the frequencies at which QC tests should be conducted did not correspond to the recommended standards; indicating that personnel were not familiar with QC implementation and may require further training on QC.

  9. Status, Vision, and Challenges of an Intelligent Distributed Engine Control Architecture

    Science.gov (United States)

    Behbahani, Alireza; Culley, Dennis; Garg, Sanjay; Millar, Richard; Smith, Bert; Wood, Jim; Mahoney, Tim; Quinn, Ronald; Carpenter, Sheldon; Mailander, Bill; hide

    2007-01-01

    A Distributed Engine Control Working Group (DECWG) consisting of the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) and industry has been formed to examine the current and future requirements of propulsion engine systems. The scope of this study will include an assessment of the paradigm shift from centralized engine control architecture to an architecture based on distributed control utilizing open system standards. Included will be a description of the work begun in the 1990's, which continues today, followed by the identification of the remaining technical challenges which present barriers to on-engine distributed control.

  10. Observer Based Traction/Braking Control Design for High Speed Trains Considering Adhesion Nonlinearity

    OpenAIRE

    Cai, Wenchuan; Liao, Wenhao; Li, Danyong; Song, Yongduan

    2014-01-01

    Train traction/braking control, one of the key enabling technologies for automatic train operation, literally takes its action through adhesion force. However, adhesion coefficient of high speed train (HST) is uncertain in general because it varies with wheel-rail surface condition and running speed; thus, it is extremely difficult to be measured, which makes traction/braking control design and implementation of HSTs greatly challenging. In this work, force observers are applied to estimate t...

  11. Challenges in Recruiting Aging Women Holocaust Survivors to a Case Control Study of Breast Cancer.

    Science.gov (United States)

    Vin-Raviv, Neomi; Dekel, Rachel; Barchana, Micha; Linn, Shai; Keinan-Boker, Lital

    2015-01-01

    Older adults are underrepresented in medical research for many reasons, including recruitment difficulties. Recruitment of older adults for research studies is often a time-consuming process and can be more challenging when the study involves older adults with unique exposures to traumatic events and from minority groups. The current article provides a brief overview of (a) challenges encountered while recruiting aging women Holocaust survivors for a case control study and (b) strategies used for meeting those challenges. The case group comprised women Holocaust survivors who were recently diagnosed with breast cancer and the control group comprised healthy women from a Holocaust-survivor community in Israel. Copyright 2015, SLACK Incorporated.

  12. Data Quality Control: Challenges, Methods, and Solutions from an Eco-Hydrologic Instrumentation Network

    Science.gov (United States)

    Eiriksson, D.; Jones, A. S.; Horsburgh, J. S.; Cox, C.; Dastrup, D.

    2017-12-01

    Over the past few decades, advances in electronic dataloggers and in situ sensor technology have revolutionized our ability to monitor air, soil, and water to address questions in the environmental sciences. The increased spatial and temporal resolution of in situ data is alluring. However, an often overlooked aspect of these advances are the challenges data managers and technicians face in performing quality control on millions of data points collected every year. While there is general agreement that high quantities of data offer little value unless the data are of high quality, it is commonly understood that despite efforts toward quality assurance, environmental data collection occasionally goes wrong. After identifying erroneous data, data managers and technicians must determine whether to flag, delete, leave unaltered, or retroactively correct suspect data. While individual instrumentation networks often develop their own QA/QC procedures, there is a scarcity of consensus and literature regarding specific solutions and methods for correcting data. This may be because back correction efforts are time consuming, so suspect data are often simply abandoned. Correction techniques are also rarely reported in the literature, likely because corrections are often performed by technicians rather than the researchers who write the scientific papers. Details of correction procedures are often glossed over as a minor component of data collection and processing. To help address this disconnect, we present case studies of quality control challenges, solutions, and lessons learned from a large scale, multi-watershed environmental observatory in Northern Utah that monitors Gradients Along Mountain to Urban Transitions (GAMUT). The GAMUT network consists of over 40 individual climate, water quality, and storm drain monitoring stations that have collected more than 200 million unique data points in four years of operation. In all of our examples, we emphasize that scientists

  13. An early feeding regime and a high-density amino acid diet on growth performance of broilers under subclinical necrotic enteritis challenge

    Directory of Open Access Journals (Sweden)

    Chake Keerqin

    2017-03-01

    Full Text Available Broilers that have early access to feed have been shown to have enhanced immune system and gut development and heightened resilience against necrotic enteritis (NE. This study examined the effect of early feeding a high amino acid density diet on performance of broilers under a sub-clinical NE challenge model. Ross 308 broilers (n = 576 were assigned to a 2 × 2 × 2 factorial design with 2 feeding regimes (feed access either within 6 h post-hatch or after 48 h post-hatch, 2 diets (control diet or the control diet with an additional 10% digestible amino acids [HAA] and either presence or absence of NE challenge. Oral administrations of Eimeria species (d 9 and a field strain of Clostridium perfringens (d 14 were used to induce NE. Broiler performance was analysed at d 13, 23, 30 and 35. Intestinal lesion score and bacterial count were analysed on d 16. The NE challenge reduced overall bird performance and induced severe intestinal lesions, without causing notable mortality. At d 23 bird weight was significantly lower (P < 0.001 in the challenged birds compared with the unchallenged birds, but by d 30 the challenged birds had recovered and challenge no longer had an impact on bird performance. Birds fed the HAA diet had greater body weight by d 35 and heightened Lactobacillus content in the ileum at d 16 (P < 0.05. Birds that were fed the HAA diet after a period of fasting performed better in terms of feed conversion ratio (FCR under challenge. The findings from this study suggest there are beneficial effects of feeding high amino acid diets to birds in response to external stresses, such as post-hatch fasting and subclinical NE.

  14. Cavity Control and Cooling of Nanoparticles in High Vacuum

    Science.gov (United States)

    Millen, James

    2016-05-01

    Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres, and control the rotation of nanorods, with the potential to produce cold, aligned nanostructures. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.

  15. Challenges of Control in Functional Organization Structures: Example of Outsourcing Sector

    OpenAIRE

    Agnieszka Maciejczyk

    2016-01-01

    Effective control of an organization is strictly connected with its organization structure. When a company decides to outsource a part of its operations, a new structure is applied. Also, the system of control should be reviewed and adjusted to the new model of business in order to be effective. Usually, the outsourcing companies apply functional organization structure which is the most common way of grouping business activities. The goal of the paper was to point challenges and aspects which...

  16. High School Leadership: The Challenge of Managing Resources and Competencies

    Science.gov (United States)

    Alsaaty, Falih M.; Morris, Archie, III

    2015-01-01

    High schools play a vital role in achieving and reflecting American ideals and culture. They provide the foundation for the country's economic, social, and political systems as well as the impetus for its scientific progress and technological superiority. The purpose of this study was to explore the challenges facing high schools' leadership in…

  17. Potential Challenges of Controlling Leishmaniasis in Sri Lanka at a Disease Outbreak

    Directory of Open Access Journals (Sweden)

    Tharaka Wijerathna

    2017-01-01

    Full Text Available The present works reviewed the existing information on leishmaniasis in Sri Lanka and in other countries, focusing on challenges of controlling leishmaniasis in the country, in an outbreak. Evidence from recent studies suggests that there is a possibility of a leishmaniasis outbreak in Sri Lanka in the near future. Difficulty of early diagnosis due to lack of awareness and unavailability or inadequacy of sensitive tests are two of the main challenges for effective case management. Furthermore, the absence of a proper drug for treatment and lack of knowledge about vector biology, distribution, taxonomy and bionomics, and reservoir hosts make the problem serious. The evident potential for visceralization in the cutaneous variant of L. donovani in Sri Lanka may also complicate the issue. Lack of knowledge among local communities also reduces the effectiveness of vector and reservoir host control programs. Immediate actions need to be taken in order to increase scientific knowledge about the disease and a higher effectiveness of the patient management and control programs must be achieved through increased awareness about the disease among general public and active participation of local community in control activities.

  18. Constructibility Challenges for Perimeter Control Blasting and Slope Development in Shale and Other "Weak" Rocks

    Science.gov (United States)

    Scarpato, D. J.

    2016-02-01

    Slope construction in shale can present some interesting challenges for geotechnical design engineers and contractors alike. There are challenges that can be expected and designed for; however, all too frequently, such challenges manifest themselves as "surprises" in the field. Common constructibility challenges can include drill hole deviation during drilling for controlled blasting; and, excavation slope instability arising from inconsistent perimeter control drilling. Drill hole deviation results from the cumulative effects from both drilling mechanics and rock mass conditions. Once a hole has initiated the deviation trajectory, it is difficult to rectify drill steel position. Although such challenges are not necessarily unique to shale, they are often exacerbated by weak, weathered and transversely isotropic nature of bedrock conditions. All too often, the working assumption is that shale is "soft" and easily excavatable; however, this blanket assumption can prove to be costly. This paper is intended to provide design professionals and contractors with the practical considerations needed to avoid the "surprises" associated with drill hole deviation, and minimize the potential for costly claims.

  19. Process qualification and control in electron beams--requirements, methods, new concepts and challenges

    International Nuclear Information System (INIS)

    Mittendorfer, J.; Gratzl, F.; Hanis, D.

    2004-01-01

    In this paper the status of process qualification and control in electron beam irradiation is analyzed in terms of requirements, concepts, methods and challenges for a state-of-the-art process control concept for medical device sterilization. Aspects from process qualification to routine process control are described together with the associated process variables. As a case study the 10 MeV beams at Mediscan GmbH are considered. Process control concepts like statistical process control (SPC) and a new concept to determine process capability is briefly discussed

  20. Myth 15: High-Ability Students Don't Face Problems and Challenges

    Science.gov (United States)

    Moon, Sidney M.

    2009-01-01

    One rationale for failure to address the needs of high-ability students in schools is that high-ability students do not need special services because they do not face any special problems or challenges. A more extreme corollary of this attitude is the notion that high ability is so protective that students with high ability do not face problems or…

  1. Challenges in Slug Modeling and Control for Offshore Oil and Gas Productions

    DEFF Research Database (Denmark)

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

    2017-01-01

    The upstream offshore multi-phase well-pipeline-riser installations are facing huge challenges related to slugging flow: An unstable flow regime where the flow rates, pressures and temperatures oscillate in the multi-phase pipelines. One typical severe slug is induced by vertical wells or risers...... most models require specific facility and operating data which, unfortunately, often is not available from most offshore installations. Anti-slug control have been investigated for several decades in oil & gas industry, but many of these existing methods suffer the consequent risk of simultaneously...... reducing the oil & gas production. This paper concludes that slug is a well defined phenomenon, but even though it has been investigated for several decades the current anti-slug control methods still have problems related to robustness. It is predicted that slug-induced challenges will be even more severe...

  2. Validation of novel recipes for double-blind, placebo-controlled food challenges in children and adults

    NARCIS (Netherlands)

    Vlieg-Boerstra, B. J.; Herpertz, I.; Pasker, L.; van der Heide, S.; Kukler, J.; Jansink, C.; Vaessen, W.; Beusekamp, B. J.; Dubois, A. E. J.

    P>Background: In double-blind, placebo-controlled food challenges (DBPCFCs), the use of challenge materials in which blinding is validated is a prerequisite for obtaining true blinded conditions during the test procedure. Therefore, the aim of this study was to enlarge the available range of

  3. Operational challenges to feedwater/steam generator water level control

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, V.M.; Whaley, S.D.; Federico, P.A. [Westinghouse Electric Company, Cranberry Township, Pennsylvania (United States)

    2012-07-01

    Feedwater control and turbine control have historically been at the top of the list of contributors to unplanned outages and forced curtailments in the nuclear industry, and they remain so according to recent industry data. Much has been done and is available by way of measures to improve this area and, in spite of much progress, opportunities remain to extend implementation. Toward this end, this paper aims to focus upon feedwater control and provide background on associated characteristics and attributes as a context for identifying the issues which are key challenges that lie at the root of this concern. Primary groupings of these issues will be discussed in order to better define their nature and to establish a basis for a presentation of the range of solutions which have been implemented and remain available to address them. The need for a systems engineering approach, and the role of I&C and field-mounted equipment to application of these solutions will be discussed. (author)

  4. Validation of novel recipes for double-blind, placebo-controlled food challenges in children and adults

    NARCIS (Netherlands)

    Vlieg-Boerstra, B. J.; Herpertz, I.; Pasker, L.; van der Heide, S.; Kukler, J.; Jansink, C.; Vaessen, W.; Beusekamp, B. J.; Dubois, A. E. J.

    2011-01-01

    In double-blind, placebo-controlled food challenges (DBPCFCs), the use of challenge materials in which blinding is validated is a prerequisite for obtaining true blinded conditions during the test procedure. Therefore, the aim of this study was to enlarge the available range of validated recipes for

  5. Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges

    Directory of Open Access Journals (Sweden)

    Mahammad A. Hannan

    2014-12-01

    Full Text Available With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil’s mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning

  6. Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges

    Science.gov (United States)

    Hannan, Mahammad A.; Hussein, Hussein A.; Mutashar, Saad; Samad, Salina A.; Hussain, Aini

    2014-01-01

    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of

  7. High-Speed Non-Volatile Optical Memory: Achievements and Challenges

    Directory of Open Access Journals (Sweden)

    Vadym Zayets

    2017-01-01

    Full Text Available We have proposed, fabricated, and studied a new design of a high-speed optical non-volatile memory. The recoding mechanism of the proposed memory utilizes a magnetization reversal of a nanomagnet by a spin-polarized photocurrent. It was shown experimentally that the operational speed of this memory may be extremely fast above 1 TBit/s. The challenges to realize both a high-speed recording and a high-speed reading are discussed. The memory is compact, integratable, and compatible with present semiconductor technology. If realized, it will advance data processing and computing technology towards a faster operation speed.

  8. Electronics and triggering challenges for the CMS High Granularity Calorimeter

    Science.gov (United States)

    Lobanov, A.

    2018-02-01

    The High Granularity Calorimeter (HGCAL), presently being designed by the CMS collaboration to replace the CMS endcap calorimeters for the High Luminosity phase of LHC, will feature six million channels distributed over 52 longitudinal layers. The requirements for the front-end electronics are extremely challenging, including high dynamic range (0.2 fC-10 pC), low noise (~2000 e- to be able to calibrate on single minimum ionising particles throughout the detector lifetime) and low power consumption (~20 mW/channel), as well as the need to select and transmit trigger information with a high granularity. Exploiting the intrinsic precision-timing capabilities of silicon sensors also requires careful design of the front-end electronics as well as the whole system, particularly clock distribution. The harsh radiation environment and requirement to keep the whole detector as dense as possible will require novel solutions to the on-detector electronics layout. Processing the data from the HGCAL imposes equally large challenges on the off-detector electronics, both for the hardware and incorporated algorithms. We present an overview of the complete electronics architecture, as well as the performance of prototype components and algorithms.

  9. Memory controllers for high-performance and real-time MPSoCs : requirements, architectures, and future trends

    NARCIS (Netherlands)

    Akesson, K.B.; Huang, Po-Chun; Clermidy, F.; Dutoit, D.; Goossens, K.G.W.; Chang, Yuan-Hao; Kuo, Tei-Wei; Vivet, P.; Wingard, D.

    2011-01-01

    Designing memory controllers for complex real-time and high-performance multi-processor systems-on-chip is challenging, since sufficient capacity and (real-time) performance must be provided in a reliable manner at low cost and with low power consumption. This special session contains four

  10. Controller Placement Algorithms in Software Defined Network - A Review of Trends and Challenges

    Directory of Open Access Journals (Sweden)

    Yoon Si-Kee

    2017-01-01

    Full Text Available Traditional network architectures are complex to manage, comparatively static, rigid and difficult to make changes for new innovation. The proprietary devices in such architectures are based on manual configuration which are unwieldy and error-prone. Software Defined Network (SDN which is described as a new network paradigm that decouple the control plane from data plane are capable to solve today's network issues and improve the network performance. Nevertheless, among so many challenges and research opportunity in SDN, Controller Placement Problem (CPP is said to be the most important issues which can directly affect the overall network performance. Thus far, the issue regarding the CPP and its challenge has not been completely reviewed and discussed properly in any other papers. In this paper, we provide a comprehensive review on several optimized controller placement problem algorithms in SDN. This paper also highlights some limitations of the reviewed methods and also emphasizes on suitable approach to address the aforementioned problems.

  11. Invited review article: high-speed flexure-guided nanopositioning: mechanical design and control issues.

    Science.gov (United States)

    Yong, Y K; Moheimani, S O R; Kenton, B J; Leang, K K

    2012-12-01

    Recent interest in high-speed scanning probe microscopy for high-throughput applications including video-rate atomic force microscopy and probe-based nanofabrication has sparked attention on the development of high-bandwidth flexure-guided nanopositioning systems (nanopositioners). Such nanopositioners are designed to move samples with sub-nanometer resolution with positioning bandwidth in the kilohertz range. State-of-the-art designs incorporate uniquely designed flexure mechanisms driven by compact and stiff piezoelectric actuators. This paper surveys key advances in mechanical design and control of dynamic effects and nonlinearities, in the context of high-speed nanopositioning. Future challenges and research topics are also discussed.

  12. Challenges Regarding IP Core Functional Reliability

    Science.gov (United States)

    Berg, Melanie D.; LaBel, Kenneth A.

    2017-01-01

    For many years, intellectual property (IP) cores have been incorporated into field programmable gate array (FPGA) and application specific integrated circuit (ASIC) design flows. However, the usage of large complex IP cores were limited within products that required a high level of reliability. This is no longer the case. IP core insertion has become mainstream including their use in highly reliable products. Due to limited visibility and control, challenges exist when using IP cores and subsequently compromise product reliability. We discuss challenges and suggest potential solutions to critical application IP insertion.

  13. Challenges and opportunities in integration of design and control

    DEFF Research Database (Denmark)

    Huusom, Jakob Kjøbsted

    2015-01-01

    Process synthesis and design of plant operation are related topics but current industrial practice solves these problems sequentially. The implication of this sequential strategy may result in design of processing systems which are very hard to control. This paper presents a discussion on drivers...... for an integrated approach and outlines the challenges in formulation of such a multi-objective synthesis problem. This discussion is viewed in relation to some of the changing trends in the industry. Significant results have been published which in different ways seek to handle the integrated problem. Further...

  14. Influence of muscle fiber type composition on early fat accumulation under high-fat diet challenge.

    Science.gov (United States)

    Hua, Ning; Takahashi, Hirokazu; Yee, Grace M; Kitajima, Yoichiro; Katagiri, Sayaka; Kojima, Motoyasu; Anzai, Keizo; Eguchi, Yuichiro; Hamilton, James A

    2017-01-01

    To investigate whether differences in muscle fiber types affect early-stage fat accumulation, under high fat diet challenge in mice. Twelve healthy male C57BL/6 mice experienced with short-term (6 weeks) diet treatment for the evaluation of early pattern changes in muscular fat. The mice were randomly divided into two groups: high fat diet (n = 8) and normal control diet (n = 4). Extra- and intra-myocellular lipid (EMCL and IMCL) in lumbar muscles (type I fiber predominant) and tibialis anterior (TA) muscle (type II fiber predominant) were determined using magnetic resonance spectroscopy (MRS). Correlation of EMCL, IMCL and their ratio between TA and lumbar muscles was evaluated. EMCL increased greatly in both muscle types after high fat diet. IMCL in TA and lumbar muscles increased to a much lower extent, with a slightly greater increase in TA muscles. EMCLs in the 2 muscles were positively correlated (r = 0.84, p = 0.01), but IMCLs showed a negative relationship (r = -0.84, p = 0.01). In lumbar muscles, high fat diet significantly decreased type I fiber while it increased type II fiber (all p≤0.001). In TA muscle, there was no significant fiber type shifting (p>0.05). Under short-time high fat diet challenge, lipid tends to initially accumulate extra-cellularly. In addition, compared to type II dominant muscle, Type I dominant muscle was less susceptible to IMCL accumulation but more to fiber type shifting. These phenomena might reflect compensative responses of skeletal muscle to dietary lipid overload in order to regulate metabolic homeostasis.

  15. 77 FR 52105 - Announcement of the Innovation in Arms Control Challenge Under the America Competes...

    Science.gov (United States)

    2012-08-28

    ... Challenge: This Challenge seeks creative ideas from the general public to use the tools and devices commonly..., shall be incorporated in and maintaining a primary place of business in the United States, and in the... provision of the following: 1. A description of the proposed mechanism or idea to support arms control...

  16. Controlled nuclear fusion, a challenging task with a big payoff

    International Nuclear Information System (INIS)

    Noterdaeme, Jean-Marie

    2003-01-01

    Controlled thermonuclear fusion carries the promise of providing the world with a new source of energy, the same energy that powers the stars. Research in this area has progressed steadily for several decades now, and is ready to move into a new phase. The probability is high that a new international experimental machine (ITER) which will prove the scientific and technological feasibility of fusion energy, will be built. This paper introduces nuclear fusion for people familiar with the fission process. It starts from the basic principles common to fusion and fission. It moves on to point out the differences, explains the reasons for those differences and the consequences. Controlled thermonuclear fusion can be obtained in several ways, which have led to different research lines. One line, on which this talk focuses, is by confining the reacting particles with magnetic fields. Another, which is the subject of a different talk, relies on the inertia of the particles to create the conditions necessary for fusion. The progress of the magnetic confinement research is shown, with examples of major hurdles, which have occurred and have been overcome. Recent results, which make us optimistic that the next machine can prove the feasibility of fusion energy, are highlighted. The talk also addresses the challenges that remain before us, and suggests that the promise of fusion energy opens up new perspectives and opportunities for the development and the use of fission energy. (author)

  17. Identifying and evaluating high risk areas and challenges on marine drilling riser system in relation to deepwater problems

    OpenAIRE

    Iversen, Alexander

    2012-01-01

    Master's thesis in Offshore technology The main concerns during drilling operations are riser integrity and maintaining well control. This thesis has mainly been focusing on the problems and challenges faced with the marine riser system to illuminate high risk areas related to riser integrity. A marine riser system consists generally of four main elements; the upper marine riser package, riser joints, lower marine riser package, and the blowout preventer, each playing an important par...

  18. Prevention and control of high blood pressure: challenges and opportunities.

    OpenAIRE

    Campbell, N R; Chockalingam, A

    1995-01-01

    Cardiovascular disease is still the leading cause of death in developed countries and is becoming more common in the developing world. The reduction in incidence of many cardiovascular diseases in the last few decades may be attributed in part to extensive programs to reduce and manage risk factors such as hypertension. Nevertheless, untreated, uncontrolled and undiagnosed hypertension remains a significant concern. Many nations have adopted policies and programs for hypertension control. An ...

  19. Benefits and challenges of using the cohort multiple randomised controlled trial design for testing an intervention for depression.

    Science.gov (United States)

    Viksveen, Petter; Relton, Clare; Nicholl, Jon

    2017-07-06

    Trials which test the effectiveness of interventions compared with the status quo frequently encounter challenges. The cohort multiple randomised controlled trial (cmRCT) design is an innovative approach to the design and conduct of pragmatic trials which seeks to address some of these challenges. In this article, we report our experiences with the first completed randomised controlled trial (RCT) using the cmRCT design. This trial-the Depression in South Yorkshire (DEPSY) trial-involved comparison of treatment as usual (TAU) with TAU plus the offer of an intervention for people with self-reported long-term moderate to severe depression. In the trial, we used an existing large population-based cohort: the Yorkshire Health Study. We discuss our experiences with recruitment, attrition, crossover, data analysis, generalisability of results, and cost. The main challenges in using the cmRCT design were the high crossover to the control group and the lower questionnaire response rate among patients who refused the offer of treatment. However, the design did help facilitate efficient and complete recruitment of the trial population as well as analysable data that were generalisable to the population of interest. Attrition rates were also smaller than those reported in other depression trials. This first completed full trial using the cmRCT design testing an intervention for self-reported depression was associated with a number of important benefits. Further research is required to compare the acceptability and cost effectiveness of standard pragmatic RCT design with the cmRCT design. ISRCTN registry: ISRCTN02484593 . Registered on 7 Jan 2013.

  20. Signal processing and control challenges for smart vehicles

    Science.gov (United States)

    Zhang, Hui; Braun, Simon G.

    2017-03-01

    Smart phones have changed not only the mobile phone market but also our society during the past few years. Could the next potential intelligent device may be the vehicle? Judging by the visibility, in all media, of the numerous attempts to develop autonomous vehicles, this is certainly one of the logical outcomes. Smart vehicles would be equipped with an advanced operating system such that the vehicles could communicate with others, optimize the operation to reduce fuel consumption and emissions, enhance safety, or even become self-driving. These combined new features of vehicles require instrumentation and hardware developments, fast signal processing/fusion, decision making and online optimization. Meanwhile, the inevitable increasing system complexity would certainly challenges the control unit design.

  1. Cassini at Saturn Proximal Orbits - Attitude Control Challenges

    Science.gov (United States)

    Burk, Thomas A.

    2013-01-01

    The Cassini mission at Saturn will come to an end in the spring and summer of 2017 with a series of 22 orbits that will dip inside the rings of Saturn. These are called proximal orbits and will conclude with spacecraft disposal into the atmosphere of the ringed world on September 15, 2017. These unique orbits that cross the ring plane only a few thousand kilometers above the cloud tops of the planet present new attitude control challenges for the Cassini operations team. Crossing the ring plane so close to the inner edge of the rings means that the Cassini orientation during the crossing will be tailored to protect the sensitive electronics bus of the spacecraft. This orientation will put the sun sensors at some extra risk so this paper discusses how the team prepares for dust hazards. Periapsis is so close to the planet that spacecraft controllability with RCS thrusters needs to be evaluated because of the predicted atmospheric torque near closest approach to Saturn. Radiation during the ring plane crossings will likely trigger single event transients in some attitude control sensors. This paper discusses how the attitude control team deals with radiation hazards. The angular size and unique geometry of the rings and Saturn near periapsis means that star identification will be interrupted and this paper discusses how the safe mode attitude is selected to best deal with these large bright bodies during the proximal orbits.

  2. The challenge of controlling phosphorus in chronic kidney disease.

    Science.gov (United States)

    Cannata-Andía, Jorge B; Martin, Kevin J

    2016-04-01

    The pathogenesis and management of chronic kidney disease-mineral bone disorders (CKD-MBD) has experienced major changes, but the control of serum phosphorus at all stages of CKD still seems to be a key factor to improve clinical outcomes. High serum phosphorus is the most important uremia-related, non-traditional risk factor associated with vascular calcification in CKD patients and in the general population. Phosphorus may also be one of the key elements linking vascular calcification with low bone turnover. The main hormones and factors that contribute to the kidney regulation of phosphorus and calcium include parathyroid hormone, FGF-23, klotho and 1,25-dihydroxyvitamin D (1,25(OH)2D). Serum phosphorus did not start rising until CKD 3b in contrast with the earlier changes observed with fibroblast growth factor-23 (FGF-23), Klotho, calcitriol and parathyroid hormone (PTH). Despite FGF-23 and PTH having synergic effects regarding phosphorus removal, they have opposite effects on 1,25(OH)2D3. At the same stages of CKD in which phosphorus retention appears to occur, calcium retention also occurs. As phosphorus accumulation is associated with poor outcomes, an important question without a clear answer is at which level-range should serum phosphorus be maintained at different stages of CKD to improve clinical outcomes. There are four main strategies to manage phosphate homeostasis; phosphorus dietary intake, administration of phosphate binder agents, effective control of hyperparathyroidism and to ensure in the CKD 5D setting, an adequate scheme of dialysis. Despite all the available strategies, and the introduction of new phosphate binder agents in the market, controlling serum phosphorus remains challenging, and hyperphosphatemia continues to be extremely common in CKD 5 patients. Furthermore, despite phosphate binding agents having proved to be effective in reducing serum phosphorus, their ultimate effects on clinical outcomes remain controversial. Thus, we still

  3. Inspiring and Challenging Laboratory Exercise in Multivariable Control Theory – The Four-rotor Helicopter

    Directory of Open Access Journals (Sweden)

    Dag A. H. Samuelsen

    2012-12-01

    Full Text Available Engineering students in a module on multivariable control theory are given a laboratory exercise for developing their skills in practical implementation of control systems. This is done in an effort to create a more complete module that gives the students experiences in the practical sides of implementing control systems, while still being theoretically challenging and inspiring. Presenting students with this kind of real-life challenges like sub-optimal models, limited processing time and large degree of uncertainty, is a challenging task, partly due to the need of adapting the level of complexity to the student or group of students doing the exercise in order to keep them engaged throughout the exercise, and in part due to the university's need to reduce expenses related to the administration, supervision, and execution of laboratory exercises. The possibility of adapting the complexity of the exercise to each student's skill level is important, both through the design of the exercise and through the students choosing between different models. The eager student might be tempted by the better performing, but more complex models, while the struggling student can find satisfaction in stabilising the aircraft using the less complex models. The laboratory setup presented uses low-cost components, giving low investment and maintenance costs.

  4. Security, development and human rights: normative, legal and policy challenges for the international drug control system.

    Science.gov (United States)

    Barrett, Damon

    2010-03-01

    This commentary addresses some of the challenges posed by the broader normative, legal and policy framework of the United Nations for the international drug control system. The 'purposes and principles' of the United Nations are presented and set against the threat based rhetoric of the drug control system and the negative consequences of that system. Some of the challenges posed by human rights law and norms to the international drug control system are also described, and the need for an impact assessment of the current system alongside alternative policy options is highlighted as a necessary consequence of these analyses. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  5. [China faces a challenge of breast cancer prevention and control].

    Science.gov (United States)

    Zhang, B N; Chen, W Q; Zhang, X; Qiao, Y L

    2016-10-23

    The incidence and mortality of breast cancer is in an increasing trend. In contrast to the global breast cancer situation, the prevention and control is challenging in China. Some suggestions are presented to the project of breast cancer prevention and control in China. Combining the global screening experiences with the epidemiological features of Chinese female breast cancer, aims to improve the population screening and early detection rate. Standardizing clinical diagnosis and treatment practice, aims to increase the efficacy and decrease the mortality. Intervening lifestyle and dietary behaviors, and intends to reduce risk exposure and incidence. Building national breast cancer registry provides preventive strategies. Great efforts should be made to carry out large sample multicenter clinical trails and translational research on the prevention and cotrol of breast cancer coordiated by health care service and science and technology administrations. Breast cancer prevention and control has a long way to go in China.

  6. Public Health Responses to and Challenges for the Control of Dengue Transmission in High-Income Countries: Four Case Studies.

    Directory of Open Access Journals (Sweden)

    Elvina Viennet

    2016-09-01

    Full Text Available Dengue has a negative impact in low- and lower middle-income countries, but also affects upper middle- and high-income countries. Despite the efforts at controlling this disease, it is unclear why dengue remains an issue in affluent countries. A better understanding of dengue epidemiology and its burden, and those of chikungunya virus and Zika virus which share vectors with dengue, is required to prevent the emergence of these diseases in high-income countries in the future. The purpose of this review was to assess the relative burden of dengue in four high-income countries and to appraise the similarities and differences in dengue transmission. We searched PubMed, ISI Web of Science, and Google Scholar using specific keywords for articles published up to 05 May 2016. We found that outbreaks rarely occur where only Aedes albopictus is present. The main similarities between countries uncovered by our review are the proximity to dengue-endemic countries, the presence of a competent mosquito vector, a largely nonimmune population, and a lack of citizens' engagement in control of mosquito breeding. We identified important epidemiological and environmental issues including the increase of local transmission despite control efforts, population growth, difficulty locating larval sites, and increased human mobility from neighboring endemic countries. Budget cuts in health and lack of practical vaccines contribute to an increased risk. To be successful, dengue-control programs for high-income countries must consider the epidemiology of dengue in other countries and use this information to minimize virus importation, improve the control of the cryptic larval habitat, and engage the community in reducing vector breeding. Finally, the presence of a communicable disease center is critical for managing and reducing future disease risks.

  7. Public Health Responses to and Challenges for the Control of Dengue Transmission in High-Income Countries: Four Case Studies.

    Science.gov (United States)

    Viennet, Elvina; Ritchie, Scott A; Williams, Craig R; Faddy, Helen M; Harley, David

    2016-09-01

    Dengue has a negative impact in low- and lower middle-income countries, but also affects upper middle- and high-income countries. Despite the efforts at controlling this disease, it is unclear why dengue remains an issue in affluent countries. A better understanding of dengue epidemiology and its burden, and those of chikungunya virus and Zika virus which share vectors with dengue, is required to prevent the emergence of these diseases in high-income countries in the future. The purpose of this review was to assess the relative burden of dengue in four high-income countries and to appraise the similarities and differences in dengue transmission. We searched PubMed, ISI Web of Science, and Google Scholar using specific keywords for articles published up to 05 May 2016. We found that outbreaks rarely occur where only Aedes albopictus is present. The main similarities between countries uncovered by our review are the proximity to dengue-endemic countries, the presence of a competent mosquito vector, a largely nonimmune population, and a lack of citizens' engagement in control of mosquito breeding. We identified important epidemiological and environmental issues including the increase of local transmission despite control efforts, population growth, difficulty locating larval sites, and increased human mobility from neighboring endemic countries. Budget cuts in health and lack of practical vaccines contribute to an increased risk. To be successful, dengue-control programs for high-income countries must consider the epidemiology of dengue in other countries and use this information to minimize virus importation, improve the control of the cryptic larval habitat, and engage the community in reducing vector breeding. Finally, the presence of a communicable disease center is critical for managing and reducing future disease risks.

  8. Challenges and prospects for dengue and malaria control in Thailand, Southeast Asia.

    Science.gov (United States)

    Corbel, Vincent; Nosten, Francois; Thanispong, Kanutcharee; Luxemburger, Christine; Kongmee, Monthathip; Chareonviriyaphap, Theeraphap

    2013-12-01

    Despite significant advances in the search for potential dengue vaccines and new therapeutic schemes for malaria, the control of these diseases remains difficult. In Thailand, malaria incidence is falling whereas that of dengue is rising, with an increase in the proportion of reported severe cases. In the absence of antiviral therapeutic options for acute dengue, appropriate case management reduces mortality. However, the interruption of transmission still relies on vector control measures that are currently insufficient to curtail the cycle of epidemics. Drug resistance in malaria parasites is increasing, compromising malaria control and elimination. Deficiencies in our knowledge of vector biology and vectorial capacity also hinder public health efforts for vector control. Challenges to dengue and malaria control are discussed, and research priorities identified. Copyright © 2013. Published by Elsevier Ltd.

  9. Neuromechanical Control for Hexapedal Robot Walking on Challenging Surfaces and Surface Classification

    DEFF Research Database (Denmark)

    Xiong, Xiaofeng; Wörgötter, Florentin; Manoonpong, Poramate

    2014-01-01

    The neuromechanical control principles of animal locomotion provide good insights for the development of bio-inspired legged robots for walking on challenging surfaces. Based on such principles, we developed a neuromechanical controller consisting of a modular neural network (MNN) and of virtual...... agonist–antagonist muscle mechanisms (VAAMs). The controller allows for variable compliant leg motions of a hexapod robot, thereby leading to energy-efficient walking on different surfaces. Without any passive mechanisms or torque and position feedback at each joint, the variable compliant leg motions...... are achieved by only changing the stiffness parameters of the VAAMs. In addition, six surfaces can be also classified by observing the motor signals generated by the controller. The performance of the controller is tested on a physical hexapod robot. Experimental results show that it can effectively walk...

  10. Cold Plasmas for Biofilm Control: Opportunities and Challenges.

    Science.gov (United States)

    Gilmore, Brendan F; Flynn, Padrig B; O'Brien, Séamus; Hickok, Noreen; Freeman, Theresa; Bourke, Paula

    2018-06-01

    Bacterial biofilm infections account for a major proportion of chronic and medical device associated infections in humans, yet our ability to control them is compromised by their inherent tolerance to antimicrobial agents. Cold atmospheric plasma (CAP) represents a promising therapeutic option. CAP treatment of microbial biofilms represents the convergence of two complex phenomena: the production of a chemically diverse mixture of reactive species and intermediates, and their interaction with a heterogeneous 3D interface created by the biofilm extracellular polymeric matrix. Therefore, understanding these interactions and physiological responses to CAP exposure are central to effective management of infectious biofilms. We review the unique opportunities and challenges for translating CAP to the management of biofilms. Copyright © 2018. Published by Elsevier Ltd.

  11. Observer Based Traction/Braking Control Design for High Speed Trains Considering Adhesion Nonlinearity

    Directory of Open Access Journals (Sweden)

    Wenchuan Cai

    2014-01-01

    Full Text Available Train traction/braking control, one of the key enabling technologies for automatic train operation, literally takes its action through adhesion force. However, adhesion coefficient of high speed train (HST is uncertain in general because it varies with wheel-rail surface condition and running speed; thus, it is extremely difficult to be measured, which makes traction/braking control design and implementation of HSTs greatly challenging. In this work, force observers are applied to estimate the adhesion force or/and the resistance, based on which simple traction/braking control schemes are established under the consideration of actual wheel-rail adhesion condition. It is shown that the proposed controllers have simple structure and can be easily implemented from real applications. Numerical simulation also validates the effectiveness of the proposed control scheme.

  12. Security Challenges in Smart-Grid Metering and Control Systems

    Directory of Open Access Journals (Sweden)

    Xinxin Fan

    2013-07-01

    Full Text Available The smart grid is a next-generation power system that is increasingly attracting the attention of government, industry, and academia. It is an upgraded electricity network that depends on two-way digital communications between supplier and consumer that in turn give support to intelligent metering and monitoring systems. Considering that energy utilities play an increasingly important role in our daily life, smart-grid technology introduces new security challenges that must be addressed. Deploying a smart grid without adequate security might result in serious consequences such as grid instability, utility fraud, and loss of user information and energy-consumption data. Due to the heterogeneous communication architecture of smart grids, it is quite a challenge to design sophisticated and robust security mechanisms that can be easily deployed to protect communications among different layers of the smart grid-infrastructure. In this article, we focus on the communication-security aspect of a smart-grid metering and control system from the perspective of cryptographic techniques, and we discuss different mechanisms to enhance cybersecurity of the emerging smart grid. We aim to provide a comprehensive vulnerability analysis as well as novel insights on the cybersecurity of a smart grid.

  13. Remote maintenance of future fusion reactors - a challenge for rad-hard components and smart control strategies

    International Nuclear Information System (INIS)

    Decreton, M.; Geeter, J. De

    1996-01-01

    The future fusion reactor will need frequent maintenance turns, involving inspection, repair and parts replacement inside the vacuum vessel. These operations will require high payload manipulations in constrained space under very high gamma-radiation dose-rates and temperature. Present research is being undertaken to qualify the components of the handling machine under representative conditions, in the framework of the ITER international consortium. Simultaneously, challenging control strategies will be needed to achieve reliable tasking under very poor viewing conditions and elementary sensing help. The paper reviews the present state of the art on both issues and present results of the ongoing research themes among the partners of the ITER programme. In particular, SCK''centre-dot''CEN coordinates the ITER T252 task on Radiation Tolerance Assessment of Remote Handling Components. (UK)

  14. Design of High-Fidelity Testing Framework for Secure Electric Grid Control

    Energy Technology Data Exchange (ETDEWEB)

    Yoginath, Srikanth B [ORNL; Perumalla, Kalyan S [ORNL

    2014-01-01

    A solution methodology and implementation components are presented that can uncover unwanted, unintentional or unanticipated effects on electric grids from changes to actual electric grid control software. A new design is presented to leapfrog over the limitations of current modeling and testing techniques for cyber technologies in electric grids. We design a fully virtualized approach in which actual, unmodified operational software under test is enabled to interact with simulated surrogates of electric grids. It enables the software to influence the (simulated) grid operation and vice versa in a controlled, high fidelity environment. Challenges in achieving such capability include achieving low-overhead time control mechanisms in hypervisor schedulers, network capture and time-stamping, translation of network packets emanating from grid software into discrete events of virtual grid models, translation back from virtual sensors/actuators into data packets to control software, and transplanting the entire system onto an accurately and efficiently maintained virtual-time plane.

  15. High-throughput electrical characterization for robust overlay lithography control

    Science.gov (United States)

    Devender, Devender; Shen, Xumin; Duggan, Mark; Singh, Sunil; Rullan, Jonathan; Choo, Jae; Mehta, Sohan; Tang, Teck Jung; Reidy, Sean; Holt, Jonathan; Kim, Hyung Woo; Fox, Robert; Sohn, D. K.

    2017-03-01

    Realizing sensitive, high throughput and robust overlay measurement is a challenge in current 14nm and advanced upcoming nodes with transition to 300mm and upcoming 450mm semiconductor manufacturing, where slight deviation in overlay has significant impact on reliability and yield1). Exponentially increasing number of critical masks in multi-patterning lithoetch, litho-etch (LELE) and subsequent LELELE semiconductor processes require even tighter overlay specification2). Here, we discuss limitations of current image- and diffraction- based overlay measurement techniques to meet these stringent processing requirements due to sensitivity, throughput and low contrast3). We demonstrate a new electrical measurement based technique where resistance is measured for a macro with intentional misalignment between two layers. Overlay is quantified by a parabolic fitting model to resistance where minima and inflection points are extracted to characterize overlay control and process window, respectively. Analyses using transmission electron microscopy show good correlation between actual overlay performance and overlay obtained from fitting. Additionally, excellent correlation of overlay from electrical measurements to existing image- and diffraction- based techniques is found. We also discuss challenges of integrating electrical measurement based approach in semiconductor manufacturing from Back End of Line (BEOL) perspective. Our findings open up a new pathway for accessing simultaneous overlay as well as process window and margins from a robust, high throughput and electrical measurement approach.

  16. High performance leadership in unusually challenging educational circumstances

    Directory of Open Access Journals (Sweden)

    Andy Hargreaves

    2015-04-01

    Full Text Available This paper draws on findings from the results of a study of leadership in high performing organizations in three sectors. Organizations were sampled and included on the basis of high performance in relation to no performance, past performance, performance among similar peers and performance in the face of limited resources or challenging circumstances. The paper concentrates on leadership in four schools that met the sample criteria.  It draws connections to explanations of the high performance ofEstoniaon the OECD PISA tests of educational achievement. The article argues that leadership in these four schools that performed above expectations comprised more than a set of competencies. Instead, leadership took the form of a narrative or quest that pursued an inspiring dream with relentless determination; took improvement pathways that were more innovative than comparable peers; built collaboration and community including with competing schools; and connected short-term success to long-term sustainability.

  17. Attention switching after dietary brain 5-HT challenge in high impulsive subjects.

    Science.gov (United States)

    Markus, C Rob; Jonkman, Lisa M

    2007-09-01

    High levels of impulsivity have adverse effects on performance in cognitive tasks, particularLy in those tasks that require high attention investment. Furthermore, both animal and human research has indicated that reduced brain serotonin (5-HT) function is associated with increases in impulsive behaviour or decreased inhibition ability, but the effects of 5-HT challenge have not yet been investigated in subjects vulnerable to impulsivity. The present study aimed to investigate whether subjects with high trait impulsivity perform worse than low impulsive subjects in a task switching paradigm in which they have to rapidly shift their attention between two response rules, and to investigate the influence of a 5-HT enhancing diet. Healthy subjects with high ( n = 19) and low (n = 18) trait impulsivity scores participated in a double-blind placebo-controlled study. All subjects performed the attention switch task in the morning following breakfast containing either tryptophan-rich alpha-lactalbumin (4.8 g/100 g TRP) or placebo protein (1.4 g/100 g TRP). Whereas there were no baseline differences between high and low impulsive subjects in task switching abilities, high impulsive subjects made significantly more switch errors and responded slower after dietary 5-HT stimulation, whereas no dietary effects were found on task switching performance in low-impulsive subjects. The deterioration in task switching performance induced by the 5-HT enhancing diet in high impulsive subjects was suggested to be established by general arousal/attention-reducing effects of 5-HT, which might have a larger impact in high impulsive subjects due to either different brain circuitry involved in task switching in this group or lower baseline arousal levels.

  18. Qualitative Assessment of Challenges in Tuberculosis Control in West Gojjam Zone, Northwest Ethiopia: Health Workers’ and Tuberculosis Control Program Coordinators’ Perspectives

    Directory of Open Access Journals (Sweden)

    Senedu B. Gebreegziabher

    2016-01-01

    Full Text Available Background. Weak health systems pose many barriers to effective tuberculosis (TB control. This study aimed at exploring health worker’s and TB control program coordinator’s perspectives on health systems challenges facing TB control in West Gojjam Zone, Amhara Region, Ethiopia. Methods. This was a qualitative descriptive study. Eight in-depth interviews with TB control program coordinators and two focus group discussions among 16 health workers were conducted. Purposive sampling was used to recruit study participants. Thematic analysis was used to identify and analyse main themes. Results. We found that intermittent interruptions of laboratory reagents and anti-TB drugs supplies, absence of trained and motivated health workers, poor TB data documentation, lack of adherence to TB treatment guideline, and lack of access to TB diagnostic tools at peripheral health institutions were challenges facing the TB control program performance in the study zone. Conclusions. Ensuring uninterrupted supply of anti-TB drugs and laboratory reagents to all health institutions is essential. Continuous refresher training of health workers on standard TB care and data handling and developing and implementing a sound retention strategy to attract and motivate health professionals to work in rural areas are necessary interventions to improve the TB control program performance in the study zone.

  19. Challenges as enablers for high quality Linked Data: insights from the Semantic Publishing Challenge

    Directory of Open Access Journals (Sweden)

    Anastasia Dimou

    2017-01-01

    Full Text Available While most challenges organized so far in the Semantic Web domain are focused on comparing tools with respect to different criteria such as their features and competencies, or exploiting semantically enriched data, the Semantic Web Evaluation Challenges series, co-located with the ESWC Semantic Web Conference, aims to compare them based on their output, namely the produced dataset. The Semantic Publishing Challenge is one of these challenges. Its goal is to involve participants in extracting data from heterogeneous sources on scholarly publications, and producing Linked Data that can be exploited by the community itself. This paper reviews lessons learned from both (i the overall organization of the Semantic Publishing Challenge, regarding the definition of the tasks, building the input dataset and forming the evaluation, and (ii the results produced by the participants, regarding the proposed approaches, the used tools, the preferred vocabularies and the results produced in the three editions of 2014, 2015 and 2016. We compared these lessons to other Semantic Web Evaluation Challenges. In this paper, we (i distill best practices for organizing such challenges that could be applied to similar events, and (ii report observations on Linked Data publishing derived from the submitted solutions. We conclude that higher quality may be achieved when Linked Data is produced as a result of a challenge, because the competition becomes an incentive, while solutions become better with respect to Linked Data publishing best practices when they are evaluated against the rules of the  challenge.

  20. Challenges and Approaches to Statistical Design and Inference in High Dimensional Investigations

    Science.gov (United States)

    Garrett, Karen A.; Allison, David B.

    2015-01-01

    Summary Advances in modern technologies have facilitated high-dimensional experiments (HDEs) that generate tremendous amounts of genomic, proteomic, and other “omic” data. HDEs involving whole-genome sequences and polymorphisms, expression levels of genes, protein abundance measurements, and combinations thereof have become a vanguard for new analytic approaches to the analysis of HDE data. Such situations demand creative approaches to the processes of statistical inference, estimation, prediction, classification, and study design. The novel and challenging biological questions asked from HDE data have resulted in many specialized analytic techniques being developed. This chapter discusses some of the unique statistical challenges facing investigators studying high-dimensional biology, and describes some approaches being developed by statistical scientists. We have included some focus on the increasing interest in questions involving testing multiple propositions simultaneously, appropriate inferential indicators for the types of questions biologists are interested in, and the need for replication of results across independent studies, investigators, and settings. A key consideration inherent throughout is the challenge in providing methods that a statistician judges to be sound and a biologist finds informative. PMID:19588106

  1. Challenges and approaches to statistical design and inference in high-dimensional investigations.

    Science.gov (United States)

    Gadbury, Gary L; Garrett, Karen A; Allison, David B

    2009-01-01

    Advances in modern technologies have facilitated high-dimensional experiments (HDEs) that generate tremendous amounts of genomic, proteomic, and other "omic" data. HDEs involving whole-genome sequences and polymorphisms, expression levels of genes, protein abundance measurements, and combinations thereof have become a vanguard for new analytic approaches to the analysis of HDE data. Such situations demand creative approaches to the processes of statistical inference, estimation, prediction, classification, and study design. The novel and challenging biological questions asked from HDE data have resulted in many specialized analytic techniques being developed. This chapter discusses some of the unique statistical challenges facing investigators studying high-dimensional biology and describes some approaches being developed by statistical scientists. We have included some focus on the increasing interest in questions involving testing multiple propositions simultaneously, appropriate inferential indicators for the types of questions biologists are interested in, and the need for replication of results across independent studies, investigators, and settings. A key consideration inherent throughout is the challenge in providing methods that a statistician judges to be sound and a biologist finds informative.

  2. Challenges and Ideas from a Research Program on High Quality, Evidence-Based Practice in School Mental Health

    Science.gov (United States)

    Weist, Mark D.; Youngstrom, Eric A.; Stephan, Sharon; Lever, Nancy; Fowler, Johnathan; Taylor, Leslie; McDaniel, Heather; Chappelle, Lori; Paggeot, Samantha; Hoagwood, Kimberly

    2013-01-01

    Objective Reviews the progression of a research program designed to develop, implement and study the implementation of “achievable” evidence-based practices (EBPs) in schools. Reviews challenges encountered and ideas to overcome them to enhance this avenue of research. Method Presents two federally funded randomized controlled trials involving comparison of a four-component targeted intervention (Quality Assessment and Improvement, Family Engagement and Empowerment, Modular Evidence-Based Practice, Implementation Support) versus a comparison intervention focused on Personal Wellness. In both studies primary aims focused on changes in clinician attitudes and behavior, including the delivery of high quality, evidence-based practices and secondary aims focused on student level impacts. Results A number of challenges, many not reported in the literature are reviewed, and ideas for overcoming them are presented. Conclusions Given the reality that the majority of youth mental health services are delivered in schools and the potential of school mental health (SMH) services to provide a continuum of mental health care from promotion to intervention, it is critical that the field consider and address the logistical and methodological challenges associated with implementing and studying EBP implementation by clinicians. PMID:24063310

  3. Challenges and ideas from a research program on high-quality, evidence-based practice in school mental health.

    Science.gov (United States)

    Weist, Mark D; Youngstrom, Eric A; Stephan, Sharon; Lever, Nancy; Fowler, Johnathan; Taylor, Leslie; McDaniel, Heather; Chappelle, Lori; Paggeot, Samantha; Hoagwood, Kimberly

    2014-01-01

    This article reviews the progression of a research program designed to develop, implement, and study the implementation of "achievable" evidence-based practices (EBPs) in schools. We review challenges encountered and ideas to overcome them to enhance this avenue of research. The article presents two federally funded randomized controlled trials involving comparison of a four-component targeted intervention (Quality Assessment and Improvement, Family Engagement and Empowerment, Modular Evidence-Based Practice, Implementation Support) versus a comparison intervention focused on personal wellness. In both studies, primary aims focused on changes in clinician attitudes and behavior, including the delivery of high-quality EBPs and secondary aims focused on student-level impacts. A number of challenges, many not reported in the literature, are reviewed, and ideas for overcoming them are presented. Given the reality that the majority of youth mental health services are delivered in schools and the potential of school mental health services to provide a continuum of mental health care from promotion to intervention, it is critical that the field consider and address the logistical and methodological challenges associated with implementing and studying EBP implementation by clinicians.

  4. Smoking control: challenges and achievements.

    Science.gov (United States)

    Silva, Luiz Carlos Corrêa da; Araújo, Alberto José de; Queiroz, Ângela Maria Dias de; Sales, Maria da Penha Uchoa; Castellano, Maria Vera Cruz de Oliveira

    2016-01-01

    Smoking is the most preventable and controllable health risk. Therefore, all health care professionals should give their utmost attention to and be more focused on the problem of smoking. Tobacco is a highly profitable product, because of its large-scale production and great number of consumers. Smoking control policies and treatment resources for smoking cessation have advanced in recent years, showing highly satisfactory results, particularly in Brazil. However, there is yet a long way to go before smoking can be considered a controlled disease from a public health standpoint. We can already perceive that the behavior of our society regarding smoking is changing, albeit slowly. Therefore, pulmonologists have a very promising area in which to work with their patients and the general population. We must act with greater impetus in support of health care policies and social living standards that directly contribute to improving health and quality of life. In this respect, pulmonologists can play a greater role as they get more involved in treating smokers, strengthening anti-smoking laws, and demanding health care policies related to lung diseases. RESUMO O tabagismo é o fator de risco mais prevenível e controlável em saúde e, por isso, precisa ter a máxima atenção e ser muito mais enfocado por todos os profissionais da saúde. O tabaco é um produto de alta rentabilidade pela sua grande produção e pelo elevado número de consumidores. As políticas de controle e os recursos terapêuticos para o tabagismo avançaram muito nos últimos anos e têm mostrado resultados altamente satisfatórios, particularmente no Brasil. Entretanto, ainda resta um longo caminho a ser percorrido para que se possa considerar o tabagismo como uma doença controlada sob o ponto de vista da saúde pública. Já se observam modificações do comportamento da sociedade com relação ao tabagismo, mas ainda em escala muito lenta, de modo que os pneumologistas têm nesse setor um campo

  5. Ethical Overview of Placebo Control in Psychiatric Research - Concepts and Challenges.

    Science.gov (United States)

    Ćurković, Marko; Živković, Maja; Radić, Krešimir; Vilibić, Maja; Ćelić, Ivan; Bagarić, Dario

    2015-06-01

    Permissibility of placebo controls in psychiatric research is raising everlasting controversies. The main ethical issue remains: whether, when, under what conditions, and to what extent is it justifiable to disregard subject's present (best) interest for the presumably "greater" ones. In relation to this main ethical concern, two distinct arguments arose: proponents of placebo controls trials (placebo ortxodoxy) and proponents of active controls trials (active-control orthodoxy). More recently, in new ethical guidelines, Declaration of Helsinki and International Ethical Guidelines for Biomedical Research Involving Human Subjects, a "middle way" approach was formulated, acceptable to both sides of the argument, saying placebo controls can be justified under certain conditions: when and only when, they firstly present undisputed methodological reasoning, and secondly, fulfill certain ethical considerations - mainly regarding the permissibility of accompanied risks. These ethical evaluations are inevitably contextual and evoke the need for the principle of proportionality. In scope of recent findings of substantial and progressively increasing placebo response in psychiatric research, contextual factors are identified and both theoretical and practical challenges are discussed.

  6. Advancing the management and control of typhoid fever: a review of the historical role of human challenge studies.

    Science.gov (United States)

    Waddington, Claire S; Darton, Thomas C; Woodward, William E; Angus, Brian; Levine, Myron M; Pollard, Andrew J

    2014-05-01

    Typhoid infection causes considerable morbidity and mortality worldwide, particularly in settings where lack of clean water and inadequate sanitation facilitate disease spread through faecal-oral transmission. Improved understanding of the pathogenesis, immune control and microbiology of Salmonella Typhi infection can help accelerate the development of improved vaccines and diagnostic tests necessary for disease control. S. Typhi is a human-restricted pathogen; therefore animal models are limited in their relevance to human infection. During the latter half of the 20th century, induced human infection ("challenge") studies with S. Typhi were used effectively to assess quantitatively the human host response to challenge and to measure directly the efficacy of typhoid vaccines in preventing clinical illness. Here, the findings of these historic challenge studies are reviewed, highlighting the pivotal role that challenge studies have had in improving our understanding of the host-pathogen interaction, and illustrating issues relevant to modern typhoid challenge model design. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  7. Control switching in high performance and fault tolerant control

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2010-01-01

    The problem of reliability in high performance control and in fault tolerant control is considered in this paper. A feedback controller architecture for high performance and fault tolerance is considered. The architecture is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization. By usi...

  8. Residential High-Rise Clusters as a Contemporary Planning Challenge in Manama

    Directory of Open Access Journals (Sweden)

    Florian Wiedmann

    2015-08-01

    Full Text Available This paper analyzes the different roots of current residential high-rise clusters emerging in new city districts along the coast of Bahrain’s capital city Manama, and the resulting urban planning and design challenges. Since the local real-estate markets were liberalized in Bahrain in 2003, the population grew rapidly to more than one million inhabitants. Consequently, the housing demand increased rapidly due to extensive immigration. Many residential developments were however constructed for the upper spectrum of the real-estate market, due to speculative tendencies causing a raise in land value. The emerging high-rise clusters are developed along the various waterfronts of Manama on newly reclaimed land. This paper explores the spatial consequences of the recent boom in construction boom and the various challenges for architects and urban planners to enhance urban qualities.

  9. Sensitivity of the appetite control system in obese subjects to nutritional and serotoninergic challenges.

    Science.gov (United States)

    Hill, A J; Blundell, J E

    1990-03-01

    The sensitivity of the appetite system of a group of obese individuals was assessed in response to two challenges known to reduce hunger and enhance satiety in lean people. The challenges were the presentation of a caloric (high protein) load and the activation of serotonin systems. Eight obese female adults (BMI = 38) received 2 X 15 mg d-fenfluramine or placebo daily for 3 days, the study conforming to a 2 X 2 factor (drug X lunch type), double blind, repeated measures design. Three hours after dosing on day 3 they ate either a high carbohydrate (63 percent of total energy) or high protein (54 percent) lunchtime meal (the caloric load). These fixed meal challenges were equal in energy (475 kcal), weight and fat content. Ratings of hunger motivation and food preferences were tracked over the course of lunch and for a further 3 hours, at which point subjects returned for a self-selection test meal. Intakes from this second open meal revealed significant main effects of both caloric load and drug on energy intake, with the high protein d-fenfluramine combination being the most potent anorectic pairing. These findings were supported by the profiles of hunger motivation. This study has confirmed that the appetite system of these subjects was responsive to these biologically relevant challenges. The results suggest that the combination of an appetite modulating drug with specific dietary intervention may represent an effective strategy for the management of hunger arising from caloric restriction.

  10. Leadership Challenges in ISS Operations: Lessons Learned from Junior and Senior Mission Control Personnel

    Science.gov (United States)

    Clement, James L.; Ritsher, Jennifer Boyd; Saylor, Stephanie A.; Kanas, Nick

    2006-01-01

    The International Space Station (ISS) is operated by a multi-national, multi-organizational team that is dispersed across multiple locations, time zones, and work schedules. At NASA, both junior and senior mission control personnel have had to find ways to address the leadership challenges inherent in such work, but neither have had systematic training in how to do so. The goals of this study were to examine the major leadership challenges faced by ISS mission control personnel and to highlight the approaches that they have found most effective to surmount them. We pay particular attention to the approaches successfully employed by the senior personnel and to the training needs identified by the junior personnel. We also evaluate the extent to which responses are consistent across the junior and senior samples. Further, we compare the issues identified by our interview survey to those identified by a standardized questionnaire survey of mission control personnel and a contrasting group of space station crewmembers. We studied a sample of 14 senior ISS flight controllers and a contrasting sample of 12 more junior ISS controllers. Data were collected using a semi-structured qualitative interview and content analyzed using an iterative process with multiple coders and consensus meetings to resolve discrepancies. To further explore the meaning of the interview findings, we also conducted new analyses of data from a previous questionnaire study of 13 American astronauts, 17 Russian cosmonauts, and 150 U.S. and 36 Russian mission control personnel supporting the ISS or Mir space stations. The interview data showed that the survey respondents had substantial consensus on several leadership challenges and on key strategies for dealing with them, and they offered a wide range of specific tactics for implementing these strategies. Interview data from the junior respondents will be presented for the first time at the meeting. The questionnaire data showed that the US mission

  11. Applied & Computational MathematicsChallenges for the Design and Control of Dynamic Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D L; Burns, J A; Collis, S; Grosh, J; Jacobson, C A; Johansen, H; Mezic, I; Narayanan, S; Wetter, M

    2011-03-10

    The Energy Independence and Security Act of 2007 (EISA) was passed with the goal 'to move the United States toward greater energy independence and security.' Energy security and independence cannot be achieved unless the United States addresses the issue of energy consumption in the building sector and significantly reduces energy consumption in buildings. Commercial and residential buildings account for approximately 40% of the U.S. energy consumption and emit 50% of CO{sub 2} emissions in the U.S. which is more than twice the total energy consumption of the entire U.S. automobile and light truck fleet. A 50%-80% improvement in building energy efficiency in both new construction and in retrofitting existing buildings could significantly reduce U.S. energy consumption and mitigate climate change. Reaching these aggressive building efficiency goals will not happen without significant Federal investments in areas of computational and mathematical sciences. Applied and computational mathematics are required to enable the development of algorithms and tools to design, control and optimize energy efficient buildings. The challenge has been issued by the U.S. Secretary of Energy, Dr. Steven Chu (emphasis added): 'We need to do more transformational research at DOE including computer design tools for commercial and residential buildings that enable reductions in energy consumption of up to 80 percent with investments that will pay for themselves in less than 10 years.' On July 8-9, 2010 a team of technical experts from industry, government and academia were assembled in Arlington, Virginia to identify the challenges associated with developing and deploying newcomputational methodologies and tools thatwill address building energy efficiency. These experts concluded that investments in fundamental applied and computational mathematics will be required to build enabling technology that can be used to realize the target of 80% reductions in energy

  12. The challenge of gun control for mental health advocates.

    Science.gov (United States)

    Pandya, Anand

    2013-09-01

    Mass shootings, such as the 2012 Newtown massacre, have repeatedly led to political discourse about limiting access to guns for individuals with serious mental illness. Although the political climate after such tragic events poses a considerable challenge to mental health advocates who wish to minimize unsympathetic portrayals of those with mental illness, such media attention may be a rare opportunity to focus attention on risks of victimization of those with serious mental illness and barriers to obtaining psychiatric care. Current federal gun control laws may discourage individuals from seeking psychiatric treatment and describe individuals with mental illness using anachronistic, imprecise, and gratuitously stigmatizing language. This article lays out potential talking points that may be useful after future gun violence.

  13. Micro controller application as x-ray machine's high voltage controller

    International Nuclear Information System (INIS)

    Wiranto Budi Santoso; Beny Syawaludin

    2010-01-01

    The micro controller application as x-ray machine's high voltage controller has been carried out. The purpose of this micro controller application is to give an accurate high voltage supply to the x-ray tube so that the x ray machine could produce the result as expected. The micro controller based X-ray machine's high voltage controller receives an input voltage from the keypad. This input value is displayed in the LCD (Liquid Crystal Display) screen. Then micro controller uses this input data to drive the stepper motor. The stepper motor adjusts the high voltage auto transformer's output according to the input value. The micro controller is programmed using BASCOM-B051 compiler. The test results show that the stepper motor could rotate according to an input value. (author)

  14. JACoW Challenges of the ALICE Detector Control System for the LHC RUN3

    CERN Document Server

    Chochula, Peter; Bond, Peter; Kurepin, Alexander; Lechman, Mateusz; Lang, John; Pinazza, Ombretta

    2018-01-01

    The ALICE Detector Control System (DCS) has provided its services to the experiment since 10 years. During this period it ensured uninterrupted operation of the experiment and guaranteed stable conditions for the data taking. The DCS has been designed to cope with the detector requirements compatible with the LHC operation during its RUN1 and RUN2 phases. The decision to extend the lifetime of the experiment beyond this horizon requires the redesign of the DCS data flow and represents a major challenge. The major challenges of the system upgrade are presented in this paper.

  15. The main challenges that remain in applying high-throughput sequencing to clinical diagnostics.

    Science.gov (United States)

    Loeffelholz, Michael; Fofanov, Yuriy

    2015-01-01

    Over the last 10 years, the quality, price and availability of high-throughput sequencing instruments have improved to the point that this technology may be close to becoming a routine tool in the diagnostic microbiology laboratory. Two groups of challenges, however, have to be resolved in order to move this powerful research technology into routine use in the clinical microbiology laboratory. The computational/bioinformatics challenges include data storage cost and privacy concerns, requiring analysis to be performed without access to cloud storage or expensive computational infrastructure. The logistical challenges include interpretation of complex results and acceptance and understanding of the advantages and limitations of this technology by the medical community. This article focuses on the approaches to address these challenges, such as file formats, algorithms, data collection, reporting and good laboratory practices.

  16. Optimising molecular diagnostic capacity for effective control of tuberculosis in high-burden settings.

    Science.gov (United States)

    Sabiiti, W; Mtafya, B; Kuchaka, D; Azam, K; Viegas, S; Mdolo, A; Farmer, E C W; Khonga, M; Evangelopoulos, D; Honeyborne, I; Rachow, A; Heinrich, N; Ntinginya, N E; Bhatt, N; Davies, G R; Jani, I V; McHugh, T D; Kibiki, G; Hoelscher, M; Gillespie, S H

    2016-08-01

    The World Health Organization's 2035 vision is to reduce tuberculosis (TB) associated mortality by 95%. While low-burden, well-equipped industrialised economies can expect to see this goal achieved, it is challenging in the low- and middle-income countries that bear the highest burden of TB. Inadequate diagnosis leads to inappropriate treatment and poor clinical outcomes. The roll-out of the Xpert(®) MTB/RIF assay has demonstrated that molecular diagnostics can produce rapid diagnosis and treatment initiation. Strong molecular services are still limited to regional or national centres. The delay in implementation is due partly to resources, and partly to the suggestion that such techniques are too challenging for widespread implementation. We have successfully implemented a molecular tool for rapid monitoring of patient treatment response to anti-tuberculosis treatment in three high TB burden countries in Africa. We discuss here the challenges facing TB diagnosis and treatment monitoring, and draw from our experience in establishing molecular treatment monitoring platforms to provide practical insights into successful optimisation of molecular diagnostic capacity in resource-constrained, high TB burden settings. We recommend a holistic health system-wide approach for molecular diagnostic capacity development, addressing human resource training, institutional capacity development, streamlined procurement systems, and engagement with the public, policy makers and implementers of TB control programmes.

  17. Control of energy and matter at nanoscales: challenges and opportunities for plasma nanoscience in a sustainability age

    International Nuclear Information System (INIS)

    Ostrikov, Kostya

    2011-01-01

    Plasma nanoscience is an emerging multidisciplinary research field at the cutting edge of a large number of disciplines including but not limited to physics and chemistry of plasmas and gas discharges, materials science, surface science, nanoscience and nanotechnology, solid-state physics, space physics and astrophysics, photonics, optics, plasmonics, spintronics, quantum information, physical chemistry, biomedical sciences and related engineering subjects. This paper examines the origin, progress and future perspectives of this research field driven by the global scientific and societal challenges. The future potential of plasma nanoscience to remain a highly topical area in the global research and technological agenda in the age of fundamental-level control for a sustainable future is assessed using a framework of the five Grand Challenges for Basic Energy Sciences recently mapped by the US Department of Energy. It is concluded that the ongoing research is very relevant and is expected to substantially expand to competitively contribute to the solution of all of these Grand Challenges. The approach to controlling energy and matter at nano- and subnanoscales is based on identifying the prevailing carriers and transfer mechanisms of the energy and matter at the spatial and temporal scales that are most relevant to any particular nanofabrication process. Strong accent is made on the competitive edge of the plasma-based nanotechnology in applications related to the major socio-economic issues (energy, food, water, health and environment) that are crucial for a sustainable development of humankind. Several important emerging topics, opportunities and multidisciplinary synergies for plasma nanoscience are highlighted. The main nanosafety issues are also discussed and the environment- and human health-friendly features of plasma-based nanotech are emphasized.

  18. Control of energy and matter at nanoscales: challenges and opportunities for plasma nanoscience in a sustainability age

    Science.gov (United States)

    (Ken Ostrikov, Kostya

    2011-05-01

    Plasma nanoscience is an emerging multidisciplinary research field at the cutting edge of a large number of disciplines including but not limited to physics and chemistry of plasmas and gas discharges, materials science, surface science, nanoscience and nanotechnology, solid-state physics, space physics and astrophysics, photonics, optics, plasmonics, spintronics, quantum information, physical chemistry, biomedical sciences and related engineering subjects. This paper examines the origin, progress and future perspectives of this research field driven by the global scientific and societal challenges. The future potential of plasma nanoscience to remain a highly topical area in the global research and technological agenda in the age of fundamental-level control for a sustainable future is assessed using a framework of the five Grand Challenges for Basic Energy Sciences recently mapped by the US Department of Energy. It is concluded that the ongoing research is very relevant and is expected to substantially expand to competitively contribute to the solution of all of these Grand Challenges. The approach to controlling energy and matter at nano- and subnanoscales is based on identifying the prevailing carriers and transfer mechanisms of the energy and matter at the spatial and temporal scales that are most relevant to any particular nanofabrication process. Strong accent is made on the competitive edge of the plasma-based nanotechnology in applications related to the major socio-economic issues (energy, food, water, health and environment) that are crucial for a sustainable development of humankind. Several important emerging topics, opportunities and multidisciplinary synergies for plasma nanoscience are highlighted. The main nanosafety issues are also discussed and the environment- and human health-friendly features of plasma-based nanotech are emphasized.

  19. Interface-controlled, high-mobility organic transistors

    NARCIS (Netherlands)

    Jurchescu, Oana D.; Popinciuc, Mihaita; van Wees, Bart J.; Palstra, Thomas T. M.

    2007-01-01

    The achievement of high mobilities in field-effect transistors (FETs) is one of the main challenges for the widespread application of organic conductors in devices. Good device performance of a single-crystal pentacene FET requires both removal of impurity molecules from the bulk and the

  20. Methodologies for nuclear material accounting and control: challenges and expectations

    International Nuclear Information System (INIS)

    Ramakumar, K.L.

    2007-01-01

    Nuclear Material Accounting and Control (NUMAC) represents one of the most important and indispensable responsibilities of any nuclear installation. The emphasis is to ensure that the nuclear material being handled in the nuclear installation is properly accounted for with the expected accuracy and confidence levels. A number of analytical methods based on both destructive and non-destructive assay techniques are available at the disposal of the nuclear analytical scientists for this purpose and they have been enumerated extensively in literature. Instead of recounting the analytical methodologies available, an attempt has been made in this paper to highlight some of the challenges. (author)

  1. Physics Challenges for ERL Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Lia Merminga

    2004-07-01

    We present an overview of the physics challenges encountered in the design and operation of Energy Recovering Linac (ERL) based light sources. These challenges include the generation and preservation of low emittance, high-average current beams, manipulating and preserving the transverse and longitudinal phase space, control of the multipass beam breakup instability, efficient extraction of higher order mode power and RF control and stability of the superconducting cavities. These key R&D issues drive the design and technology choices for proposed ERL light sources. Simulations and calculations of these processes will be presented and compared with experimental data obtained at the Jefferson Lab FEL Upgrade, a 10 mA ERL light source presently in commissioning, and during a 1 GeV demonstration of energy recovery at CEBAF.

  2. Perceptions of healthcare professionals regarding the main challenges and barriers to effective hospital infection control in Mongolia: a qualitative study

    Directory of Open Access Journals (Sweden)

    Ider Bat-Erdene

    2012-07-01

    Full Text Available Abstract Background It is not fully understood why healthcare decision-makers of developing countries often give low priority to infection control and why they are unable to implement international guidelines. This study aimed to identify the main perceived challenges and barriers that hinder the effective implementation of infection control programmes in Mongolia. Methods In 2008, qualitative research involving 4 group and 55 individual interviews was conducted in the capital city of Mongolia and two provincial centres. Results A total of 87 health professionals participated in the study, including policy and hospital-level managers, doctors, nurses and infection control practitioners. Thematic analysis revealed a large number of perceived challenges and barriers to the formulation and implementation of infection control policy. These challenges and barriers were complex in nature and related to poor funding, suboptimal knowledge and attitudes, and inadequate management. The study results suggest that the availability of infection control policy and guidelines, and the provision of specific recommendations for low-resource settings, do not assure effective implementation of infection control programmes. Conclusions The current infection control system in Mongolia is likely to remain ineffective unless the underlying barriers and challenges are adequately addressed. Multifaceted interventions with logistical, educational and management components that are specific to local circumstances need to be designed and implemented in Mongolia. The importance of international peer support is highlighted.

  3. Distributed control software of high-performance control-loop algorithm

    CERN Document Server

    Blanc, D

    1999-01-01

    The majority of industrial cooling and ventilation plants require the control of complex processes. All these processes are highly important for the operation of the machines. The stability and reliability of these processes are leading factors identifying the quality of the service provided. The control system architecture and software structure, as well, are required to have high dynamical performance and robust behaviour. The intelligent systems based on PID or RST controllers are used for their high level of stability and accuracy. The design and tuning of these complex controllers require the dynamic model of the plant to be known (generally obtained by identification) and the desired performance of the various control loops to be specified for achieving good performances. The concept of having a distributed control algorithm software provides full automation facilities with well-adapted functionality and good performances, giving methodology, means and tools to master the dynamic process optimization an...

  4. Business trends report 2006. High oil prices ensure high activity level; What are the challenges?

    International Nuclear Information System (INIS)

    2006-01-01

    The first in a series of annual business trends reports which The Norwegian Oil Industry Association (OLF) has decided to publish. The report highlights features in the development of the global economy and the energy markets, and presents an analysis of the level of activity on the Norwegian Shelf through to 2010. It also gives a status report and outlines the challenges that lie within three important areas for the oil industry: the relationship with the external environment, health, safety and working environment, and personnel and competence requirements within the industry. The main message contained in the report is summarised as follows: 'While prospects for the immediate future look good, we foresee a lack of new, important and technically challenging projects in the longer term. Discoveries made on the Norwegian Shelf during recent years have been small. Exploration activity must be intensified and its results must be improved. The most important and effective stimulus in this connection is new prospective exploration acreage. The Comprehensive Management Plan for Lofoten and the Barents Sea will be revised in 2010. By that time the knowledge gaps in the plan have to be filled so that the decision-making basis is as good as possible. Even though the level of activity looks as if it will continue to be high in the medium term, we have no time to lose.' Environmental status and challenges are briefly reviewed, as well as the industry's future recruitment challenges (author) (ml)

  5. New Challenges for Computing in High Energy Physics

    International Nuclear Information System (INIS)

    Santoro, Alberto

    2003-01-01

    In view of the new scientific programs established for the LHC (Large Hadron Collider) era, the way to face the technological challenges in computing was develop a new concept of GRID computing. We show some examples and, in particular, a proposal for high energy physicists in countries like Brazil. Due to the big amount of data and the need of close collaboration it will be impossible to work in research centers and universities very far from Fermilab or CERN unless a GRID architecture is built. An important effort is being made by the international community to up to date their computing infrastructure and networks

  6. ESSD: Real World Issues and Challenges of High-Quality Data Publication

    Science.gov (United States)

    Pfeiffenberger, Hans; Carlson, David

    2013-04-01

    The Copernicus data publication journal Earth System Science Data (ESSD) represents an important and unique (and by no means final!) step forward in the larger world of data publication. Working with authors, reviewers, editors and data centres, ESSD has successfully produced many high-quality data publications across a wide variety of scientific disciplines, for individual data sets, multiple data sets as the product of scientific consortia and in special issues coordinated with other science journals. The ESSD success also exposes issues and challenges for present and future data publication, particularly around the topic and implementation of persistent identifiers. • As ESSD encourages redundant data sets across multiple data centres for access and archive purposes, how will DOIs be employed to accurately point to those distributed or replicated data? How can authenticity and integrity be verified? • How can or should object identifiers be employed in pointing from raw to quality-controlled and finally derived data processing levels; how can we designate or distinguish among these, particularly as those terms vary substantially among, for example, geophysical and ecological communities? Likewise, how to distinguish an auto-generated data product (e.g a species identification from GBIF) from a high-effort expertly reviewed data product (e.g. an ESSD publication)? • For a growing number of ESSD data publications with expected annual or periodic revisions and updates, how should data journals' and the repositories' use of persistent identifiers best record the subsequent versions, extensions or corrections? • As published data sets become a valued part of high profile science, with attendant deadlines, announcements and publicity, do the various DOI policies and minting practices among cooperating publishers, data centres and journals represent a help or a hindrance? These questions evolve directly from increasing interest in and activity by ESSD and, as

  7. Protective effects of high-potency FMDV O1 Manisa monovalent vaccine in cattle challenged with FMDV O/SKR/2010 at 7 or 4 days post vaccination.

    Science.gov (United States)

    Horsington, Jacquelyn; Perez, Claudia Beascoechea; Maradei, Eduardo; Novo, Sabrina Galdo; Gonzales, Jose L; Singanallur, Nagendrakumar B; Bonastre, Paula; Vosloo, Wilna

    2017-09-12

    Serotype O foot-and-mouth disease (FMD) virus belonging to the SEA topotype continues to be a significant problem in the Eastern Asia region, with outbreaks in Japan and South Korea resulting in the culling of over 3.5 million cattle and pigs in recent years. High-potency O1 Manisa vaccine was previously shown to provide protection in cattle 21days post vaccination (dpv) following challenge with a representative virus, O/SKR/2010. This study tested the ability of the O1 Manisa vaccine to protect cattle from infection and disease with the O/SKR/2010 virus within just 4 or 7days post vaccination. The vaccine protected 50% of cattle from clinical disease when administered 7days prior to challenge, but was not protective with just 4days between vaccination and challenge. Viraemia was significantly reduced in animals challenged 7 dpv but not 4 dpv, compared to unvaccinated controls, however, there were no effects on the level of virus detected in nasal and oral secretions regardless of vaccination time. The level of neutralising antibodies detected in cattle challenged 7 dpv correlated with protection from clinical disease. All animals seroconverted to FMDV non-structural proteins, suggesting no sterile protection. An equal number of animals became persistently infected in both vaccine groups. The results indicated that high-potency O1 Manisa vaccine administered just 7days prior to challenge should provide partial protection of cattle if an outbreak of O/SKR/2010, or related viruses, occurs, and would be useful to limit spread of FMDV when used in conjunction with other control measures. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Technological challenges in thermal plasma production

    International Nuclear Information System (INIS)

    Ramakrishnan, S.

    1995-01-01

    Thermal plasmas, generated by electric arc discharges, are used in a variety of industrial applications. The electric arc is a constricted electrical discharge with a high temperature in the range 6000-25,000 K. These characteristics are useful in plasma cutting, spraying, welding and specific areas of material processing. The thermal plasma technology is an enabling process technology and its status in the market depends upon its advantages over competing technologies. A few technological challenges to enhance the status of plasma technology are to improve the utilisation of the unique characteristics of the electric arc and to provide enhanced control of the process. In particular, new solutions are required for increasing the plasma-material interaction, controlling the electrode roots and controlling the thermal power generated by the arcing process. In this paper, the advantages of plasma technology, its constraints and future challenges for technology developments are highlighted. 36 refs., 14 figs

  9. Exclusively breastfed infants at risk for false negative double blind placebo controlled milk challenge

    NARCIS (Netherlands)

    Petrus, N. C. M.; Kole, E. A.; Schoemaker, A. A.; van Aalderen, W. M. C.; Sprikkelman, A. B.

    2014-01-01

    The double blind placebo controlled food challenge (DBPCFC) is the gold standard for diagnosing cow's milk allergy (CMA). However, false-negative DBPCFC have been reported. We present 2 cases with a false negative DBPCFC in exclusively breastfed infants suspected of CMA. These cases highlight the

  10. Long-term intake of a high prebiotic fiber diet but not high protein reduces metabolic risk after a high fat challenge and uniquely alters gut microbiota and hepatic gene expression.

    Science.gov (United States)

    Saha, Dolan C; Reimer, Raylene A

    2014-09-01

    A mismatch between early developmental diet and adulthood may increase obesity risk. Our objective was to determine the effects of re-matching rats to their weaning diets high in protein or fiber after transient high-fat/high-sucrose challenge in adulthood. We hypothesize that a long-term high fiber diet will be associated with a gut microbiota and hepatic gene expression reflective of reduced adiposity. Wistar rat pups were fed a control (C), high prebiotic fiber (HF), or high protein (HP) diet from 3-15 weeks of age; a high-fat/high-sucrose diet from 15-21 weeks; their respective C, HF, or HP diets from 21-25 weeks. Gut microbiota of cecal contents and hepatic gene expression were measured when rats were terminated at 25 weeks of age. HF rats had higher total bacteria, bifidobacteria and Bacteroides/Prevotella spp than C and HP at 25 weeks (P diet attenuated the typical increase in Firmicutes:Bacteroidetes ratio associated with consumption of a high fat diet. Lower hepatic cholesterol with long-term HF diet intake may be related to alterations in gut microbiota and hepatic lipid metabolism. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Presidential Green Chemistry Challenge: 1999 Designing Greener Chemicals Award

    Science.gov (United States)

    Presidential Green Chemistry Challenge 1999 award winner, Dow AgroSciences, developed spinosad, a highly selective, low-toxicity, nonpersistant insecticide made by a soil microorganism. It controls many chewing insect pests.

  12. Materials control and accountability challenges associated with plutonium inventories

    International Nuclear Information System (INIS)

    Crawford, D.W.

    1996-01-01

    There are currently many initiatives underway within the Department of Energy (DOE) to safely and securely manage large plutonium inventories arising from weapons dismantlement, changing missions and facility operations. Plutonium inventory information is increasingly accessible to the public as a result of the secretary of energy's openness initiative. As a result, knowledge of these inventories and levels to which the department has accounted for and controlled these inventories, will be under increased scrutiny from a variety of interest groups. The quality of this accountability data and what this data means will greatly influence the public's perception of how the US is protecting its plutonium inventories. In addition, the department's safeguards program provides an essential basis for the application of International Atomic Energy Agency (IAEA) safeguards that, in addition to possibly other international control regimes, will be in place over a large portion of these future inventories. The capability and functionality of the department's nuclear safeguards program will be important contributors to the success of US programs for the responsible stewardship of these vast plutonium inventories. This paper discusses some of the challenges, in terms of specific issues relating to one part of the department's safeguards program--materials control and accountability (MC and A)--to meet the growing domestic and international requirements and expectations associated with these plutonium inventories

  13. Materials control and accountability challenges associated with plutonium inventories

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, D.W. [USDOE Office of Safeguards and Security, Washington, DC (United States)

    1996-07-01

    There are currently many initiatives underway within the Department of Energy (DOE) to safely and securely manage large plutonium inventories arising from weapons dismantlement, changing missions and facility operations. Plutonium inventory information is increasingly accessible to the public as a result of the secretary of energy`s openness initiative. As a result, knowledge of these inventories and levels to which the department has accounted for and controlled these inventories, will be under increased scrutiny from a variety of interest groups. The quality of this accountability data and what this data means will greatly influence the public`s perception of how the US is protecting its plutonium inventories. In addition, the department`s safeguards program provides an essential basis for the application of International Atomic Energy Agency (IAEA) safeguards that, in addition to possibly other international control regimes, will be in place over a large portion of these future inventories. The capability and functionality of the department`s nuclear safeguards program will be important contributors to the success of US programs for the responsible stewardship of these vast plutonium inventories. This paper discusses some of the challenges, in terms of specific issues relating to one part of the department`s safeguards program--materials control and accountability (MC and A)--to meet the growing domestic and international requirements and expectations associated with these plutonium inventories.

  14. High Luminosity LHC: challenges and plans

    Science.gov (United States)

    Arduini, G.; Barranco, J.; Bertarelli, A.; Biancacci, N.; Bruce, R.; Brüning, O.; Buffat, X.; Cai, Y.; Carver, L. R.; Fartoukh, S.; Giovannozzi, M.; Iadarola, G.; Li, K.; Lechner, A.; Medina Medrano, L.; Métral, E.; Nosochkov, Y.; Papaphilippou, Y.; Pellegrini, D.; Pieloni, T.; Qiang, J.; Redaelli, S.; Romano, A.; Rossi, L.; Rumolo, G.; Salvant, B.; Schenk, M.; Tambasco, C.; Tomás, R.; Valishev, S.; Van der Veken, F. F.

    2016-12-01

    The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up a new energy frontier for exploration in 2010, it has gathered a global user community working in fundamental particle physics and the physics of hadronic matter at extreme temperature and density. To sustain and extend its discovery potential, the LHC will undergo a major upgrade in the 2020s. This will increase its rate of collisions by a factor of five beyond the original design value and the integrated luminosity by a factor ten. The new configuration, known as High Luminosity LHC (HL-LHC), will rely on a number of key innovations that push accelerator technology beyond its present limits. Among these are cutting-edge 11-12 T superconducting magnets, including Nb3Sn-based magnets never used in accelerators before, compact superconducting cavities for longitudinal beam rotation, new technology and physical processes for beam collimation. The dynamics of the HL-LHC beams will be also particularly challenging and this aspect is the main focus of this paper.

  15. High Luminosity LHC: Challenges and plans

    International Nuclear Information System (INIS)

    Arduini, G.; Barranco, J.; Bertarelli, A.; Biancacci, N.; Bruce, R.

    2016-01-01

    The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up a new energy frontier for exploration in 2010, it has gathered a global user community working in fundamental particle physics and the physics of hadronic matter at extreme temperature and density. To sustain and extend its discovery potential, the LHC will undergo a major upgrade in the 2020s. This will increase its rate of collisions by a factor of five beyond the original design value and the integrated luminosity by a factor ten. The new configuration, known as High Luminosity LHC (HL-LHC), will rely on a number of key innovations that push accelerator technology beyond its present limits. Among these are cutting-edge 11–12 T superconducting magnets, including Nb 3 Sn-based magnets never used in accelerators before, compact superconducting cavities for longitudinal beam rotation, new technology and physical processes for beam collimation. As a result, the dynamics of the HL-LHC beams will be also particularly challenging and this aspect is the main focus of this paper.

  16. Band-selective shaped pulse for high fidelity quantum control in diamond

    International Nuclear Information System (INIS)

    Chang, Yan-Chun; Xing, Jian; Liu, Gang-Qin; Jiang, Qian-Qing; Li, Wu-Xia; Zhang, Fei-Hao; Gu, Chang-Zhi; Pan, Xin-Yu; Long, Gui-Lu

    2014-01-01

    High fidelity quantum control of qubits is crucially important for realistic quantum computing, and it becomes more challenging when there are inevitable interactions between qubits. We introduce a band-selective shaped pulse, refocusing BURP (REBURP) pulse, to cope with the problems. The electron spin of nitrogen-vacancy centers in diamond is flipped with high fidelity by the REBURP pulse. In contrast with traditional rectangular pulses, the shaped pulse has almost equal excitation effect in a sharply edged region (in frequency domain). So the three sublevels of host 14 N nuclear spin can be flipped accurately simultaneously, while unwanted excitations of other sublevels (e.g., of a nearby 13 C nuclear spin) is well suppressed. Our scheme can be used for various applications such as quantum metrology, quantum sensing, and quantum information process.

  17. Band-selective shaped pulse for high fidelity quantum control in diamond

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yan-Chun; Xing, Jian; Liu, Gang-Qin; Jiang, Qian-Qing; Li, Wu-Xia [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, Fei-Hao [Tsinghua National Laboratory for Information Science and Technology, Beijing 100084 (China); State Key Laboratory of Low-Dimensional Physics and Department of Physics, Tsinghua University, Beijing 100084 (China); Gu, Chang-Zhi; Pan, Xin-Yu, E-mail: xypan@aphy.iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China); Long, Gui-Lu [Tsinghua National Laboratory for Information Science and Technology, Beijing 100084 (China); State Key Laboratory of Low-Dimensional Physics and Department of Physics, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)

    2014-06-30

    High fidelity quantum control of qubits is crucially important for realistic quantum computing, and it becomes more challenging when there are inevitable interactions between qubits. We introduce a band-selective shaped pulse, refocusing BURP (REBURP) pulse, to cope with the problems. The electron spin of nitrogen-vacancy centers in diamond is flipped with high fidelity by the REBURP pulse. In contrast with traditional rectangular pulses, the shaped pulse has almost equal excitation effect in a sharply edged region (in frequency domain). So the three sublevels of host {sup 14}N nuclear spin can be flipped accurately simultaneously, while unwanted excitations of other sublevels (e.g., of a nearby {sup 13}C nuclear spin) is well suppressed. Our scheme can be used for various applications such as quantum metrology, quantum sensing, and quantum information process.

  18. Improved Hybrid Fireworks Algorithm-Based Parameter Optimization in High-Order Sliding Mode Control of Hypersonic Vehicles

    Directory of Open Access Journals (Sweden)

    Xiaomeng Yin

    2018-01-01

    Full Text Available With respect to the nonlinear hypersonic vehicle (HV dynamics, achieving a satisfactory tracking control performance under uncertainties is always a challenge. The high-order sliding mode control (HOSMC method with strong robustness has been applied to HVs. However, there are few methods for determining suitable HOSMC parameters for an efficacious control of HV, given that the uncertainties are randomly distributed. In this study, we introduce a hybrid fireworks algorithm- (FWA- based parameter optimization into HV control design to satisfy the design requirements with high probability. First, the complex relation between design parameters and the cost function that evaluates the likelihood of system instability and violation of design requirements is modeled via stochastic robustness analysis. Subsequently, we propose an efficient hybrid FWA to solve the complex optimization problem concerning the uncertainties. The efficiency of the proposed hybrid FWA-based optimization method is demonstrated in the search of the optimal HV controller, in which the proposed method exhibits a better performance when compared with other algorithms.

  19. Opportunities and Challenges of AC/DC Transmission Network Planning Considering High Proportion Renewable Energy

    Directory of Open Access Journals (Sweden)

    Arslan Habib

    2018-03-01

    Full Text Available The time and space distribution characteristics of future high proportion of renewable energy sources will bring unprecedented challenges to the electric power system’s processing and planning, the basic form of electric power system and operating characteristics will have fundamental changes. Based on the research status quo at home and abroad, this paper expounds the four scientific problems of the transmission network planning with high proportion of renewable energy. Respectively, from the network source collaborative planning, transmission network flexible planning. With the distribution network in conjunction with the transmission network planning, transmission planning program comprehensive evaluation and decision-making methods. This paper puts forward the research ideas and framework of transmission network planning considering the high proportion of renewable energy. At the end, the future high proportion of (renewable energy grid-connected transmission network’s opportunities and challenges are presented.

  20. Controlled Human Malaria Infection: Applications, Advances, and Challenges.

    Science.gov (United States)

    Stanisic, Danielle I; McCarthy, James S; Good, Michael F

    2018-01-01

    Controlled human malaria infection (CHMI) entails deliberate infection with malaria parasites either by mosquito bite or by direct injection of sporozoites or parasitized erythrocytes. When required, the resulting blood-stage infection is curtailed by the administration of antimalarial drugs. Inducing a malaria infection via inoculation with infected blood was first used as a treatment (malariotherapy) for neurosyphilis in Europe and the United States in the early 1900s. More recently, CHMI has been applied to the fields of malaria vaccine and drug development, where it is used to evaluate products in well-controlled early-phase proof-of-concept clinical studies, thus facilitating progression of only the most promising candidates for further evaluation in areas where malaria is endemic. Controlled infections have also been used to immunize against malaria infection. Historically, CHMI studies have been restricted by the need for access to insectaries housing infected mosquitoes or suitable malaria-infected individuals. Evaluation of vaccine and drug candidates has been constrained in these studies by the availability of a limited number of Plasmodium falciparum isolates. Recent advances have included cryopreservation of sporozoites, the manufacture of well-characterized and genetically distinct cultured malaria cell banks for blood-stage infection, and the availability of Plasmodium vivax -specific reagents. These advances will help to accelerate malaria vaccine and drug development by making the reagents for CHMI more widely accessible and also enabling a more rigorous evaluation with multiple parasite strains and species. Here we discuss the different applications of CHMI, recent advances in the use of CHMI, and ongoing challenges for consideration. Copyright © 2017 American Society for Microbiology.

  1. Nuclear export controls and the CTBT: Where we`ve been and challenges ahead -- Views of an engineer

    Energy Technology Data Exchange (ETDEWEB)

    Lundy, A.S.

    1998-09-01

    The paper discusses the following topics: the importance of export controls; the uniqueness of nuclear weapons and their export control requirements; ``dual-use`` controls; and recent developments in nonproliferation beyond export control. Also discussed are some non-obvious challenges which include computer modeling and visualization, and fissile material availability and instant nukes. The author concludes by asking the Nuclear Suppliers Group to consider whether there are ways to make its controls more effective.

  2. Nuclear export controls and the CTBT: Where we've been and challenges ahead - Views of an engineer

    International Nuclear Information System (INIS)

    Lundy, A.S.

    1998-01-01

    The paper discusses the following topics: the importance of export controls; the uniqueness of nuclear weapons and their export control requirements; ''dual-use'' controls; and recent developments in nonproliferation beyond export control. Also discussed are some non-obvious challenges which include computer modeling and visualization, and fissile material availability and instant nukes. The author concludes by asking the Nuclear Suppliers Group to consider whether there are ways to make its controls more effective

  3. TARGETING THE SEMEN DERIVED AMYLOIDS TO CONTROL HIV TRANSMISSION: PERSPECTIVES AND CHALLENGE

    Directory of Open Access Journals (Sweden)

    Shalini Gour

    2016-03-01

    Full Text Available Since the discovery of Acquired Immuno Deficiency Syndrome (AIDS in 1981 in United States, there have been tremendous efforts to reduce the rate of HIV transmission. Although, the epidemic is stabilized in most of the affected regions, its occurrence is reasonably evident in Eastern Europe and Central Asia due to high rate of new HIV infections. It is surprising to know that despite the high rate of infection, the virus is a weak pathogen. This paradox has been answered by a recent discovery stating that human semen contains a proteinaceous factor derived from prostatic acid phosphatase (PAP, which is commonly known as PAP248-286 peptide, plays an important role in enhancing the HIV infectivity. It forms well-defined amyloid structure, frequently referred as Semen-derived Enhancer of Viral Infection (SEVI and enhances HIV infection up to 1,00,000 fold. Serendipitous discovery of this semen derived amyloid has provided an opportunity to design an alternative approach to dismantle the mechanism of HIV infection. It is a need of the hour to search and design novel molecules and compounds that can help in destabilizing SEVI under natural conditions. In this direction, a number of molecules have been identified that have shown promising results under laboratory conditions. However, there are several critical issues that remain untouched and their addressal is highly recommended in order to develop an effective regime to control the HIV transmission via sexual route. This review is an effort to consolidate major challenges in developing a therapeutic strategy against semen derived amyloids to combat HIV transmission.

  4. Progress in nanoscale dry processes for fabrication of high-aspect-ratio features: How can we control critical dimension uniformity at the bottom?

    Science.gov (United States)

    Ishikawa, Kenji; Karahashi, Kazuhiro; Ishijima, Tatsuo; Cho, Sung Il; Elliott, Simon; Hausmann, Dennis; Mocuta, Dan; Wilson, Aaron; Kinoshita, Keizo

    2018-06-01

    In this review, we discuss the progress of emerging dry processes for nanoscale fabrication of high-aspect-ratio features, including emerging design technology for manufacturability. Experts in the fields of plasma processing have contributed to addressing the increasingly challenging demands of nanoscale deposition and etching technologies for high-aspect-ratio features. The discussion of our atomic-scale understanding of physicochemical reactions involving ion bombardment and neutral transport presents the major challenges shared across the plasma science and technology community. Focus is placed on advances in fabrication technology that control surface reactions on three-dimensional features, as well as state-of-the-art techniques used in semiconductor manufacturing with a brief summary of future challenges.

  5. Accelerator physics and technology challenges of very high energy hadron colliders

    Science.gov (United States)

    Shiltsev, Vladimir D.

    2015-08-01

    High energy hadron colliders have been in the forefront of particle physics for more than three decades. At present, international particle physics community considers several options for a 100 TeV proton-proton collider as a possible post-LHC energy frontier facility. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This paper briefly reviews the accelerator physics and technology challenges of the future very high energy colliders and outlines the areas of required research and development towards their technical and financial feasibility.

  6. Challenges for malaria elimination in Brazil.

    Science.gov (United States)

    Ferreira, Marcelo U; Castro, Marcia C

    2016-05-20

    Brazil currently contributes 42 % of all malaria cases reported in the Latin America and the Caribbean, a region where major progress towards malaria elimination has been achieved in recent years. In 2014, malaria burden in Brazil (143,910 microscopically confirmed cases and 41 malaria-related deaths) has reached its lowest levels in 35 years, Plasmodium falciparum is highly focal, and the geographic boundary of transmission has considerably shrunk. Transmission in Brazil remains entrenched in the Amazon Basin, which accounts for 99.5 % of the country's malaria burden. This paper reviews major lessons learned from past and current malaria control policies in Brazil. A comprehensive discussion of the scientific and logistic challenges that may impact malaria elimination efforts in the country is presented in light of the launching of the Plan for Elimination of Malaria in Brazil in November 2015. Challenges for malaria elimination addressed include the high prevalence of symptomless and submicroscopic infections, emerging anti-malarial drug resistance in P. falciparum and Plasmodium vivax and the lack of safe anti-relapse drugs, the largely neglected burden of malaria in pregnancy, the need for better vector control strategies where Anopheles mosquitoes present a highly variable biting behaviour, human movement, the need for effective surveillance and tools to identify foci of infection in areas with low transmission, and the effects of environmental changes and climatic variability in transmission. Control actions launched in Brazil and results to come are likely to influence control programs in other countries in the Americas.

  7. High-speed precision motion control

    CERN Document Server

    Yamaguchi, Takashi; Pang, Chee Khiang

    2011-01-01

    Written for researchers and postgraduate students in Control Engineering, as well as professionals in the Hard Disk Drive industry, this book discusses high-precision and fast servo controls in Hard Disk Drives (HDDs). The editors present a number of control algorithms that enable fast seeking and high precision positioning, and propose problems from commercial products, making the book valuable to researchers in HDDs. Each chapter is self contained, and progresses from concept to technique, present application examples that can be used within automotive, aerospace, aeronautical, and manufactu

  8. Responses to high-fat challenges varying in fat type in subjects with different metabolic risk phenotypes: a randomized trial.

    Directory of Open Access Journals (Sweden)

    Susan J van Dijk

    Full Text Available The ability of subjects to respond to nutritional challenges can reflect the flexibility of their biological system. Nutritional challenge tests could be used as an indicator of health status but more knowledge on metabolic and immune responses of different subjects to nutritional challenges is needed. The aim of this study was to compare the responses to high-fat challenges varying in fat type in subjects with different metabolic risk phenotypes.In a cross-over design 42 men (age 50-70 y consumed three high-fat shakes containing saturated fat (SFA, monounsaturated fat (MUFA or n-3 polyunsaturated (PUFA. Men were selected on BMI and health status (lean, obese or obese diabetic and phenotyped with MRI for adipose tissue distribution. Before and 2 and 4 h after shake consumption blood was drawn for measurement of expression of metabolic and inflammation-related genes in peripheral blood mononuclear cells (PBMCs, plasma triglycerides (TAG, glucose, insulin, cytokines and ex vivo PBMC immune response capacity. The MUFA and n-3 PUFA challenge, compared to the SFA challenge, induced higher changes in expression of inflammation genes MCP1 and IL1β in PBMCs. Obese and obese diabetic subjects had different PBMC gene expression and metabolic responses to high-fat challenges compared to lean subjects. The MUFA challenge induced the most pronounced TAG response, mainly in obese and obese diabetic subjects.The PBMC gene expression response and metabolic response to high-fat challenges were affected by fat type and metabolic risk phenotype. Based on our results we suggest using a MUFA challenge to reveal differences in response capacity of subjects.ClinicalTrials.gov NCT00977262.

  9. Bringing high-performance computing to the biologist's workbench: approaches, applications, and challenges

    International Nuclear Information System (INIS)

    Oehmen, C S; Cannon, W R

    2008-01-01

    Data-intensive and high-performance computing are poised to significantly impact the future of biological research which is increasingly driven by the prevalence of high-throughput experimental methodologies for genome sequencing, transcriptomics, proteomics, and other areas. Large centers such as NIH's National Center for Biotechnology Information, The Institute for Genomic Research, and the DOE's Joint Genome Institute) have made extensive use of multiprocessor architectures to deal with some of the challenges of processing, storing and curating exponentially growing genomic and proteomic datasets, thus enabling users to rapidly access a growing public data source, as well as use analysis tools transparently on high-performance computing resources. Applying this computational power to single-investigator analysis, however, often relies on users to provide their own computational resources, forcing them to endure the learning curve of porting, building, and running software on multiprocessor architectures. Solving the next generation of large-scale biology challenges using multiprocessor machines-from small clusters to emerging petascale machines-can most practically be realized if this learning curve can be minimized through a combination of workflow management, data management and resource allocation as well as intuitive interfaces and compatibility with existing common data formats

  10. Electronics and triggering challenges for the CMS High Granularity Calorimeter

    CERN Document Server

    Lobanov, Artur

    2017-01-01

    The High Granularity Calorimeter (HGCAL), presently being designed by the CMS collaboration to replace the CMS endcap calorimeters for the High Luminosity phase of LHC, will feature six million channels distributed over 52 longitudinal layers. The requirements for the front-end electronics are extremely challenging, including high dynamic range (0-10 pC), low noise (~2000e- to be able to calibrate on single minimum ionising particles throughout the detector lifetime) and low power consumption (~10mW/channel), as well as the need to select and transmit trigger information with a high granularity. Exploiting the intrinsic precision-timing capabilities of silicon sensors also requires careful design of the front-end electronics as well as the whole system, particularly clock distribution. The harsh radiation environment and requirement to keep the whole detector as dense as possible will require novel solutions to the on-detector electronics layout. Processing all the data from the HGCAL imposes equally large ch...

  11. Brain-heart interactions: challenges and opportunities with functional magnetic resonance imaging at ultra-high field.

    Science.gov (United States)

    Chang, Catie; Raven, Erika P; Duyn, Jeff H

    2016-05-13

    Magnetic resonance imaging (MRI) at ultra-high field (UHF) strengths (7 T and above) offers unique opportunities for studying the human brain with increased spatial resolution, contrast and sensitivity. However, its reliability can be compromised by factors such as head motion, image distortion and non-neural fluctuations of the functional MRI signal. The objective of this review is to provide a critical discussion of the advantages and trade-offs associated with UHF imaging, focusing on the application to studying brain-heart interactions. We describe how UHF MRI may provide contrast and resolution benefits for measuring neural activity of regions involved in the control and mediation of autonomic processes, and in delineating such regions based on anatomical MRI contrast. Limitations arising from confounding signals are discussed, including challenges with distinguishing non-neural physiological effects from the neural signals of interest that reflect cardiorespiratory function. We also consider how recently developed data analysis techniques may be applied to high-field imaging data to uncover novel information about brain-heart interactions. © 2016 The Author(s).

  12. The regulatory control of radiation sources in Australia -- The challenges of a federal system

    International Nuclear Information System (INIS)

    Loy, J.; Colgan, P.

    2001-01-01

    The report refers to the challenges that Australia is facing, as a federal nation having a Commonwealth Government and six States and two territories, in establishing appropriate regulatory control of radiation sources. Information on the national inventory of radiation sources and existing regulatory infrastructure, including the system of notification, registration, licensing, inspection and enforcement, is explained in the report. The national provisions for the management of disused sources; the planning, preparedness and response to abnormal events and emergencies; the recovery of control over orphan sources; and education and training; are specifically emphasized. (author)

  13. High-speed elevators controlled by inverters

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Yoshio; Takahashi, Hideaki; Nakamura, Kiyoshi; Kinoshita, Hiroshi

    1988-10-25

    The super-high-speed elevator with superiority to 300m/min of speed, requires both the large capacity power and wide range speed controls. Therefore, in order to materialize the smooth and quiet operation characteristics, by applying the inverter control, the low torque ripple control in the low frequency range and high frequency large capacity inverting for lowering the motor in noise are necessary with their being assured of reliability. To satisfy the above necessary items, together with the development of a sine wave pulse width and frequency modulation (PWM/PFM) control system, to more precisely enable the sine wave electric current control, and 3kHz switching power converter, using a 800A power transistor module, a supervoltage control circuit under the extraordinary condition was designed. As a result of commercializing a 360m/min super-high speed inverter elevator, the power source unit, due to the effect of high power factor, could be reduced by 30% in capacity and also the higher harmonic wave including ratio could be considerably lowered to the inferiority to 5%. 2 references, 7 figures, 1 table.

  14. Challenges in high temperature low cycle fatigue testing of metallic materials

    International Nuclear Information System (INIS)

    Sandhya, R.; Valsan, M.; Bhanu Sankara Rao, K.

    2007-01-01

    The evaluation of the high strain Low Cycle Fatigue properties of structural materials is an involved and complicated procedure requiring skill and diligence from the experimentalist. This presentation describes the various testing methods to evaluate the LCF properties of structural materials, the complexities involved and some solutions to exacting requirements, not covered by the testing procedure standards. The basic components of servo-hydraulic fatigue testing machines is described, as are the calibration and maintenance procedures. Results of LCF tests conducted at the authors' laboratory on AISI 316L(N) stainless steel and Mod.9Cr-1Mo ferritic steel are described. The complications in total strain controlled testing of weld joints is brought out and soft zone development in Mod. 9Cr-1Mo ferritic steel is described. The special requirements for testing in environmental chambers is a challenging task. In-house chambers, designed to carry out testing in dynamic sodium environment is highlighted. These chambers have provision to accommodate extensometers for strain measurements, and also house all the safety instrumentation needed to carry out to mechanical testing in dynamic sodium environment. The variation of LCF results as a function of specimen geometry is examined. The various failure criteria adopted by laboratories in different countries are also touched upon. (author)

  15. Malaria eradication: the economic, financial and institutional challenge.

    Science.gov (United States)

    Mills, Anne; Lubell, Yoel; Hanson, Kara

    2008-12-11

    Malaria eradication raises many economic, financial and institutional challenges. This paper reviews these challenges, drawing on evidence from previous efforts to eradicate malaria, with a special focus on resource-poor settings; summarizes more recent evidence on the challenges, drawing on the literature on the difficulties of scaling-up malaria control and strengthening health systems more broadly; and explores the implications of these bodies of evidence for the current call for elimination and intensified control. Economic analyses dating from the eradication era, and more recent analyses, suggest that, in general, the benefits of malaria control outweigh the costs, though few studies have looked at the relative returns to eradication versus long-term control. Estimates of financial costs are scanty and difficult to compare. In the 1960s, the consolidation phase appeared to cost less than $1 per capita and, in 1988, was estimated to be $2.31 per capita (both in 2006 prices). More recent estimates for high coverage of control measures suggest a per capita cost of several dollars. Institutional challenges faced by malaria eradication included limits to the rule of law (a major problem where malaria was concentrated in border areas with movement of people associated with illegal activities), the existence and performance of local implementing structures, and political sustainability at national and global levels. Recent analyses of the constraints to scaling-up malaria control, together with the historical evidence, are used to discuss the economic, financial and institutional challenges that face the renewed call for eradication and intensified control. The paper concludes by identifying a research agenda covering: issues of the allocative efficiency of malaria eradication, especially using macro-economic modelling to estimate the benefits and costs of malaria eradication and intensified control, and studies of the links between malaria control and economic

  16. Malaria eradication: the economic, financial and institutional challenge

    Directory of Open Access Journals (Sweden)

    Hanson Kara

    2008-12-01

    Full Text Available Abstract Malaria eradication raises many economic, financial and institutional challenges. This paper reviews these challenges, drawing on evidence from previous efforts to eradicate malaria, with a special focus on resource-poor settings; summarizes more recent evidence on the challenges, drawing on the literature on the difficulties of scaling-up malaria control and strengthening health systems more broadly; and explores the implications of these bodies of evidence for the current call for elimination and intensified control. Economic analyses dating from the eradication era, and more recent analyses, suggest that, in general, the benefits of malaria control outweigh the costs, though few studies have looked at the relative returns to eradication versus long-term control. Estimates of financial costs are scanty and difficult to compare. In the 1960s, the consolidation phase appeared to cost less than $1 per capita and, in 1988, was estimated to be $2.31 per capita (both in 2006 prices. More recent estimates for high coverage of control measures suggest a per capita cost of several dollars. Institutional challenges faced by malaria eradication included limits to the rule of law (a major problem where malaria was concentrated in border areas with movement of people associated with illegal activities, the existence and performance of local implementing structures, and political sustainability at national and global levels. Recent analyses of the constraints to scaling-up malaria control, together with the historical evidence, are used to discuss the economic, financial and institutional challenges that face the renewed call for eradication and intensified control. The paper concludes by identifying a research agenda covering: ∘ issues of the allocative efficiency of malaria eradication, especially using macro-economic modelling to estimate the benefits and costs of malaria eradication and intensified control, and studies of the links between

  17. US DOE Grand Challenge in Computational Accelerator Physics

    International Nuclear Information System (INIS)

    Ryne, R.; Habib, S.; Qiang, J.; Ko, K.; Li, Z.; McCandless, B.; Mi, W.; Ng, C.; Saparov, M.; Srinivas, V.; Sun, Y.; Zhan, X.; Decyk, V.; Golub, G.

    1998-01-01

    Particle accelerators are playing an increasingly important role in basic and applied science, and are enabling new accelerator-driven technologies. But the design of next-generation accelerators, such as linear colliders and high intensity linacs, will require a major advance in numerical modeling capability due to extremely stringent beam control and beam loss requirements, and the presence of highly complex three-dimensional accelerator components. To address this situation, the U.S. Department of Energy has approved a ''Grand Challenge'' in Computational Accelerator Physics, whose primary goal is to develop a parallel modeling capability that will enable high performance, large scale simulations for the design, optimization, and numerical validation of next-generation accelerators. In this paper we report on the status of the Grand Challenge

  18. Control room conceptual design of nuclear power plant with multiple modular high temperature gas-cooled reactors

    International Nuclear Information System (INIS)

    Jia Qianqian; Qu Ronghong; Zhang Liangju

    2014-01-01

    A conceptual design of the control room layout for the nuclear power plant with multiple modular high temperature gas-cooled reactors has been developed. The modular high temperature gas-cooled reactors may need to be grouped to produce as much energy as a utility demands to realize the economic efficiency. There are many differences between the multi-modular plant and the current NPPs in the control room. These differences may include the staffing level, the human-machine interface design, the operation mode, etc. The potential challenges of the human factor engineering (HFE) in the control room of the multi-modular plant are analyzed, including the operation workload of the multi-modular tasks, how to help the crew to keep situation awareness of all modules, and how to support team work, the control of shared system between modules, etc. A concept design of control room for the multi-modular plant is presented based on the design aspect of HTR-PM (High temperature gas-cooled reactor pebble bed module). HFE issues are considered in the conceptual design of control room for the multi-modular plant and some design strategies are presented. As a novel conceptual design, verifications and validations are needed, and focus of further work is sketch out. (author)

  19. Experimental facility for development of high-temperature reactor technology: instrumentation needs and challenges

    Directory of Open Access Journals (Sweden)

    Sabharwall Piyush

    2015-01-01

    Full Text Available A high-temperature, multi-fluid, multi-loop test facility is under development at the Idaho National Laboratory for support of thermal hydraulic materials, and system integration research for high-temperature reactors. The experimental facility includes a high-temperature helium loop, a liquid salt loop, and a hot water/steam loop. The three loops will be thermally coupled through an intermediate heat exchanger (IHX and a secondary heat exchanger (SHX. Research topics to be addressed include the characterization and performance evaluation of candidate compact heat exchangers such as printed circuit heat exchangers (PCHEs at prototypical operating conditions. Each loop will also include an interchangeable high-temperature test section that can be customized to address specific research issues associated with each working fluid. This paper also discusses needs and challenges associated with advanced instrumentation for the multi-loop facility, which could be further applied to advanced high-temperature reactors. Based on its relevance to advanced reactor systems, the new facility has been named the Advanced Reactor Technology Integral System Test (ARTIST facility. A preliminary design configuration of the ARTIST facility will be presented with the required design and operating characteristics of the various components. The initial configuration will include a high-temperature (750 °C, high-pressure (7 MPa helium loop thermally integrated with a molten fluoride salt (KF-ZrF4 flow loop operating at low pressure (0.2 MPa, at a temperature of ∼450 °C. The salt loop will be thermally integrated with the steam/water loop operating at PWR conditions. Experiment design challenges include identifying suitable materials and components that will withstand the required loop operating conditions. The instrumentation needs to be highly accurate (negligible drift in measuring operational data for extended periods of times, as data collected will be

  20. Challenges and economic implications in the control of foot and mouth disease in sub-saharan Africa: lessons from the zambian experience.

    Science.gov (United States)

    Sinkala, Y; Simuunza, M; Pfeiffer, D U; Munang'andu, H M; Mulumba, M; Kasanga, C J; Muma, J B; Mweene, A S

    2014-01-01

    Foot and mouth disease is one of the world's most important livestock diseases for trade. FMD infections are complex in nature and there are many epidemiological factors needing clarification. Key questions relate to the control challenges and economic impact of the disease for resource-poor FMD endemic countries like Zambia. A review of the control challenges and economic impact of FMD outbreaks in Zambia was made. Information was collected from peer-reviewed journals articles, conference proceedings, unpublished scientific reports, and personal communication with scientists and personal field experiences. The challenges of controlling FMD using mainly vaccination and movement control are discussed. Impacts include losses in income of over US$ 1.6 billion from exports of beef and sable antelopes and an annual cost of over US$ 2.7 million on preventive measures. Further impacts included unquantified losses in production and low investment in agriculture resulting in slow economic growth. FMD persistence may be a result of inadequate epidemiological understanding of the disease and ineffectiveness of the control measures that are being applied. The identified gaps may be considered in the annual appraisal of the FMD national control strategy in order to advance on the progressive control pathway.

  1. High Resolution Nature Runs and the Big Data Challenge

    Science.gov (United States)

    Webster, W. Phillip; Duffy, Daniel Q.

    2015-01-01

    NASA's Global Modeling and Assimilation Office at Goddard Space Flight Center is undertaking a series of very computationally intensive Nature Runs and a downscaled reanalysis. The nature runs use the GEOS-5 as an Atmospheric General Circulation Model (AGCM) while the reanalysis uses the GEOS-5 in Data Assimilation mode. This paper will present computational challenges from three runs, two of which are AGCM and one is downscaled reanalysis using the full DAS. The nature runs will be completed at two surface grid resolutions, 7 and 3 kilometers and 72 vertical levels. The 7 km run spanned 2 years (2005-2006) and produced 4 PB of data while the 3 km run will span one year and generate 4 BP of data. The downscaled reanalysis (MERRA-II Modern-Era Reanalysis for Research and Applications) will cover 15 years and generate 1 PB of data. Our efforts to address the big data challenges of climate science, we are moving toward a notion of Climate Analytics-as-a-Service (CAaaS), a specialization of the concept of business process-as-a-service that is an evolving extension of IaaS, PaaS, and SaaS enabled by cloud computing. In this presentation, we will describe two projects that demonstrate this shift. MERRA Analytic Services (MERRA/AS) is an example of cloud-enabled CAaaS. MERRA/AS enables MapReduce analytics over MERRA reanalysis data collection by bringing together the high-performance computing, scalable data management, and a domain-specific climate data services API. NASA's High-Performance Science Cloud (HPSC) is an example of the type of compute-storage fabric required to support CAaaS. The HPSC comprises a high speed Infinib and network, high performance file systems and object storage, and a virtual system environments specific for data intensive, science applications. These technologies are providing a new tier in the data and analytic services stack that helps connect earthbound, enterprise-level data and computational resources to new customers and new mobility

  2. 78 FR 48683 - Announcement of Requirements and Registration for Million Hearts® Hypertension Control Challenge

    Science.gov (United States)

    2013-08-09

    ... and integrating team-based approaches to care, as well as community approaches, such as strengthening... control hypertension may be shared in documents or other communication products that describe generally... marketing. Winners are permitted to cite that they won this challenge. The names, cities, and states of...

  3. High-temperature brushless DC motor controller

    Science.gov (United States)

    Cieslewski, Crzegorz; Lindblom, Scott C.; Maldonado, Frank J.; Eckert, Michael Nathan

    2017-05-16

    A motor control system for deployment in high temperature environments includes a controller; a first half-bridge circuit that includes a first high-side switching element and a first low-side switching element; a second half-bridge circuit that includes a second high-side switching element and a second low-side switching element; and a third half-bridge circuit that includes a third high-side switching element and a third; low-side switching element. The motor controller is arranged to apply a pulse width modulation (PWM) scheme to switch the first half-bridge circuit, second half-bridge circuit, and third half-bridge circuit to power a motor.

  4. Big data challenges

    DEFF Research Database (Denmark)

    Bachlechner, Daniel; Leimbach, Timo

    2016-01-01

    Although reports on big data success stories have been accumulating in the media, most organizations dealing with high-volume, high-velocity and high-variety information assets still face challenges. Only a thorough understanding of these challenges puts organizations into a position in which...... they can make an informed decision for or against big data, and, if the decision is positive, overcome the challenges smoothly. The combination of a series of interviews with leading experts from enterprises, associations and research institutions, and focused literature reviews allowed not only...... framework are also relevant. For large enterprises and startups specialized in big data, it is typically easier to overcome the challenges than it is for other enterprises and public administration bodies....

  5. High-resolution wavefront control of high-power laser systems

    International Nuclear Information System (INIS)

    Brase, J.; Brown, C.; Carrano, C.; Kartz, M.; Olivier, S.; Pennington, D.; Silva, D.

    1999-01-01

    Nearly every new large-scale laser system application at LLNL has requirements for beam control which exceed the current level of available technology. For applications such as inertial confinement fusion, laser isotope separation, laser machining, and laser the ability to transport significant power to a target while maintaining good beam quality is critical. There are many ways that laser wavefront quality can be degraded. Thermal effects due to the interaction of high-power laser or pump light with the internal optical components or with the ambient gas are common causes of wavefront degradation. For many years, adaptive optics based on thing deformable glass mirrors with piezoelectric or electrostrictive actuators have be used to remove the low-order wavefront errors from high-power laser systems. These adaptive optics systems have successfully improved laser beam quality, but have also generally revealed additional high-spatial-frequency errors, both because the low-order errors have been reduced and because deformable mirrors have often introduced some high-spatial-frequency components due to manufacturing errors. Many current and emerging laser applications fall into the high-resolution category where there is an increased need for the correction of high spatial frequency aberrations which requires correctors with thousands of degrees of freedom. The largest Deformable Mirrors currently available have less than one thousand degrees of freedom at a cost of approximately $1M. A deformable mirror capable of meeting these high spatial resolution requirements would be cost prohibitive. Therefore a new approach using a different wavefront control technology is needed. One new wavefront control approach is the use of liquid-crystal (LC) spatial light modulator (SLM) technology for the controlling the phase of linearly polarized light. Current LC SLM technology provides high-spatial-resolution wavefront control, with hundreds of thousands of degrees of freedom, more

  6. Inventory development for perfluorooctane sulfonic acid (PFOS) in Turkey: challenges to control chemicals in articles and products.

    Science.gov (United States)

    Korucu, M Kemal; Gedik, Kadir; Weber, Roland; Karademir, Aykan; Kurt-Karakus, Perihan Binnur

    2015-10-01

    Perfluorooctane sulfonic acid (PFOS) and related substances have been listed as persistent organic pollutants (POPs) in the Stockholm Convention. Countries which have ratified the Convention need to take appropriate actions to control PFOS use and release. This study compiles and enhances the findings of the first inventory of PFOS and related substances use in Turkey conducted within the frame of the Stockholm Convention National Implementation Plan (NIP) update. The specific Harmonized Commodity Description and Coding System (Harmonized System (HS)) codes of imported and exported goods that possibly contain PFOS and 165 of Chemical Abstracts Service (CAS) numbers of PFOS-related substances were assessed for acquiring information from customs and other authorities. However, with the current approaches available, no useful information could be compiled since HS codes are not specific enough and CAS numbers are not used by customs. Furthermore, the cut-off volume in chemical databases in Turkey and the reporting limit in the HS system (0.1 %) are too high for controlling PFOS. The attempt of modeling imported volumes by a Monte Carlo simulation did not also result in a satisfactory estimate, giving an upper-bound estimate above the global production volumes. The replies to questionnaires were not satisfactory, highlighting that an elaborated approach is needed in the communication with potentially PFOS-using stakeholders. The experience of the challenges of gathering information on PFOS in articles and products revealed the gaps of controlling highly hazardous substances in products and articles and the need of improvements.

  7. Experimental facility for development of high-temperature reactor technology: instrumentation needs and challenges - 15066

    International Nuclear Information System (INIS)

    Sabharwall, P.; O'Brien, J.E.; Yoon, S.J.; Sun, X.

    2015-01-01

    A high-temperature, multi-fluid, multi-loop test facility is under development at the Idaho National Laboratory for support of thermal hydraulic, materials, and system integration research for high-temperature reactors. The experimental facility includes a high-temperature helium loop, a liquid salt loop, and a hot water/steam loop. The 3 loops will be thermally coupled through an intermediate heat exchanger (IHX) and a secondary heat exchanger (SHX). Research topics to be addressed include the characterization and performance evaluation of candidate compact heat exchangers such as printed circuits heat exchangers (PCHEs) at prototypical operating conditions. Each loop will also include an interchangeable high-temperature test section that can be customized to address specific research issues associated with each working fluid. This paper also discusses needs and challenges associated with advanced instrumentation for the multi-loop facility, which could be further applied to advanced high-temperature reactors. Based on its relevance to advanced reactor systems, the new facility has been named the Advanced Reactor Technology Integrated System Test (ARTIST) facility. A preliminary design configuration of the ARTIST facility will be presented with the required design and operating characteristics of the various components. The initial configuration will include a high-temperature (750 C. degrees), high-pressure (7 MPa) helium loop thermally integrated with a molten fluoride salt (KF-ZrF 4 ) flow loop operating at low pressure (0.2 MPa), at a temperature of ∼ 450 C. degrees. The salt loop will be thermally integrated with the steam/water loop operating at PWR conditions. Experiment design challenges include identifying suitable materials and components that will withstand the required loop operating conditions. The instrumentation needs to be highly accurate (negligible drift) in measuring operational data for extended periods of times, as data collected will be

  8. Controlling your high blood pressure

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000101.htm Controlling your high blood pressure To use the sharing features on this page, ... JavaScript. Hypertension is another term used to describe high blood pressure. High blood pressure can lead to: Stroke Heart ...

  9. Approaches of High School Instrumental Music Educators in Response to Student Challenges

    Science.gov (United States)

    Edgar, Scott N.

    2016-01-01

    The purpose of this multiple instrumental case study was to explore approaches of four high school instrumental music educators assuming the role of facilitative teacher in responding to challenges affecting the social and emotional well-being of their students. This study utilized the framework of social emotional learning as a lens to view the…

  10. The development of a control system for a small high speed steam microturbine generator system

    Science.gov (United States)

    Alford, A.; Nichol, P.; Saunders, M.; Frisby, B.

    2015-08-01

    Steam is a widely used energy source. In many situations steam is generated at high pressures and then reduced in pressure through control valves before reaching point of use. An opportunity was identified to convert some of the energy at the point of pressure reduction into electricity. To take advantage of a market identified for small scale systems, a microturbine generator was designed based on a small high speed turbo machine. This machine was packaged with the necessary control valves and systems to allow connection of the machine to the grid. Traditional machines vary the speed of the generator to match the grid frequency. This was not possible due to the high speed of this machine. The characteristics of the rotating unit had to be understood to allow a control that allowed export of energy at the right frequency to the grid under the widest possible range of steam conditions. A further goal of the control system was to maximise the efficiency of generation under all conditions. A further complication was to provide adequate protection for the rotating unit in the event of the loss of connection to the grid. The system to meet these challenges is outlined with the solutions employed and tested for this application.

  11. Necrotic enteritis challenge and high dietary sodium level affect odorant composition or emission from broilers.

    Science.gov (United States)

    Sharma, Nishchal K; Choct, Mingan; Wu, Shu-Biao; Swick, Robert A

    2018-01-01

    Necrotic enteritis (NE) challenge and high dietary sodium (from sodium chloride) level on odor flux from broiler litter was investigated using 160 day-old Ross 308 male chicks randomly assigned to 4 dietary treatments with 4 replicates of 10 birds each. A 2 × 2 factorial arrangement of treatments was employed. Factors were: presence or absence of NE challenge and normal (1.6 g/kg) or high (4.0 g/kg) dietary sodium (Na) level. On d 20, odorants were collected from litter headspace with a flux hood and measured using selected ion flow tube mass spectrometry (SIFT-MS). On d 33, while challenge did not lead to higher mortality, it reduced feed intake by 5.48% (P litter moisture and litter headspace concentrations of dimethyl sulfide (P litter moisture (P litter headspace concentration of sulfur compounds and phenol (P litter flux of some additional odorants, which included 2,3-butanedione (P broiler farms. © 2017 Poultry Science Association Inc.

  12. Challenges for females with high functioning autism in the workplace: a systematic review.

    Science.gov (United States)

    Hayward, Susan M; McVilly, Keith R; Stokes, Mark A

    2018-02-01

    Individuals with High Functioning Autism (HFA) experience high levels of underemployment and unemployment, resulting in negative economic, social, and health outcomes. Given what is known about labor market participation difficulties experienced by women generally, and the paucity of research concerning women with HFA, this systematic review synthesized what is known about the labor market experiences of women with HFA. A systematic review of the literature concerning adult females with HFA in relation to the workplace yielded 1947 results; 11 met inclusion criteria being based on original data, but not necessarily focusing solely on women. The total number participants with HFA across all studies was 731 (M = 66.45, SD = 95.44, Mdn = 18.00) aged between 18 and 70 years (M = 34.38, SD = 7.71); females represented 38% (n = 279) of those sampled. The principal challenges reported for individuals with HFA at work were communication, social interaction, and stress, together with negative mental and physical health. These results should be interpreted with caution. Of the studies found, 73% were qualitative and based on small samples. Only one paper differentiated female data in analyses. These factors combined suggest large-scale mixed method research focused on females with HFA is required to gain an accurate insight into the challenges faced in the workplace, to in turn inform intervention and support. However, implications for rehabilitation based on what is known are discussed. Implication for Rehabilitation Unemployment and underemployment of persons with High Functioning Autism (HFA) poses social, health and economic issues for both individuals and the wider community. Those with HFA have the intellectual capacity to make a substantial contribution to the workplace. Based on what is known, some of the challenges for females with HFA might be similar to those experienced by men with HFA, however it is possible that there are gender

  13. Challenges and Economic Implications in the Control of Foot and Mouth Disease in Sub-Saharan Africa: Lessons from the Zambian Experience

    Directory of Open Access Journals (Sweden)

    Y. Sinkala

    2014-01-01

    Full Text Available Foot and mouth disease is one of the world’s most important livestock diseases for trade. FMD infections are complex in nature and there are many epidemiological factors needing clarification. Key questions relate to the control challenges and economic impact of the disease for resource-poor FMD endemic countries like Zambia. A review of the control challenges and economic impact of FMD outbreaks in Zambia was made. Information was collected from peer-reviewed journals articles, conference proceedings, unpublished scientific reports, and personal communication with scientists and personal field experiences. The challenges of controlling FMD using mainly vaccination and movement control are discussed. Impacts include losses in income of over US$ 1.6 billion from exports of beef and sable antelopes and an annual cost of over US$ 2.7 million on preventive measures. Further impacts included unquantified losses in production and low investment in agriculture resulting in slow economic growth. FMD persistence may be a result of inadequate epidemiological understanding of the disease and ineffectiveness of the control measures that are being applied. The identified gaps may be considered in the annual appraisal of the FMD national control strategy in order to advance on the progressive control pathway.

  14. Overcoming Challenges of Renewable Energy on Future Smart Grid

    Directory of Open Access Journals (Sweden)

    Olawole Joseph Petinrin

    2012-06-01

    Full Text Available The increasing complexity of the conventional grid due to population growth, advancement in technology and infrastructures which contribute immensely to instability, insecurity, and inefficiency and environmental energy sustainability calls for the use of renewable energy for sustainability of power supply. Intermittency and fluctuation of the renewable energy is a great challenge on the smart grid. This paper reveal the potential challenges of renewable energy on the smart grid and proffer solution with the application of high voltage DC (HVDC and Flexible AC transmission system (FACTS devices. The functions and advantages of FACTS devices are presented in this paper. Voltage control and stability control with FACTS application are also discussed. This was achieved because FACTS has fast controllability and capability to exchange active and reactive power independently.

  15. The national system of nuclear material control development and challenges. Vol. 3

    International Nuclear Information System (INIS)

    Badawy, I.

    1996-01-01

    This paper presents the major factors which may affect the implementation of the National System of Nuclear Material Accounting and Safeguards in Egypt. Developments of this National System-being a division of the Nuclear Regulatory Body in the country-are discussed. Also, recent requirements of the International Atomic Energy Agency within the policy of strengthening its regime of international nuclear control are reviewed. The challenges facing the National System are indicated taking in consideration the anticipated growth in the nuclear field in Egypt by the year 2000 and after. 2 figs

  16. The national system of nuclear material control development and challenges. Vol. 3

    Energy Technology Data Exchange (ETDEWEB)

    Badawy, I [National Centre for Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    This paper presents the major factors which may affect the implementation of the National System of Nuclear Material Accounting and Safeguards in Egypt. Developments of this National System-being a division of the Nuclear Regulatory Body in the country-are discussed. Also, recent requirements of the International Atomic Energy Agency within the policy of strengthening its regime of international nuclear control are reviewed. The challenges facing the National System are indicated taking in consideration the anticipated growth in the nuclear field in Egypt by the year 2000 and after. 2 figs.

  17. Challenges of influenza A viruses in humans and animals and current animal vaccines as an effective control measure

    Science.gov (United States)

    2018-01-01

    Influenza A viruses (IAVs) are genetically diverse and variable pathogens that share various hosts including human, swine, and domestic poultry. Interspecies and intercontinental viral spreads make the ecology of IAV more complex. Beside endemic IAV infections, human has been exposed to pandemic and zoonotic threats from avian and swine influenza viruses. Animal health also has been threatened by high pathogenic avian influenza viruses (in domestic poultry) and reverse zoonosis (in swine). Considering its dynamic interplay between species, prevention and control against IAV should be conducted effectively in both humans and animal sectors. Vaccination is one of the most efficient tools against IAV. Numerous vaccines against animal IAVs have been developed by a variety of vaccine technologies and some of them are currently commercially available. We summarize several challenges in control of IAVs faced by human and animals and discuss IAV vaccines for animal use with those application in susceptible populations. PMID:29399575

  18. Challenges and Opportunities for Typhoid Fever Control: A Call for Coordinated Action.

    Science.gov (United States)

    Steele, A Duncan; Hay Burgess, Deborah C; Diaz, Zoey; Carey, Megan E; Zaidi, Anita K M

    2016-03-15

    The burden of enteric fever caused by Salmonella enterica serovars Typhi and Paratyphi is substantial and has high impact in toddlers and young children. This burden is relatively well documented in Asia, and this supplement provides new data on the substantial burden in several sub-Saharan African countries. Challenges in standardized surveillance and imperfect diagnostic tools have resulted in patchy local disease data, which are not well acknowledged or integrated into local country evidence and health awareness for decision making. There is a need to strengthen diagnostics for the generation of burden data in country. Furthermore, the guidelines and training for treatment of enteric fever cases in Africa are sorely needed to help mitigate the inappropriate use of antimicrobial treatment. Classic water safety and access to sanitation development remain powerful tools for the control of typhoid fever, yet the huge economic costs and long timelines are unlikely to provide a short- to middle-term solution. Emerging threats, including multidrug resistance and increasing urbanization in regions such as sub-Saharan Africa, warrant focused attention to shorter-term interventions including immunization, and must include vaccine strategies with the new typhoid conjugate vaccines. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

  19. Engine technology challenges for a 21st century high speed civil transport

    Science.gov (United States)

    Shaw, Robert J.

    1991-01-01

    Recent NASA funded studies by Boeing and Douglas suggest an opportunity exists for a 21st Century High Speed Civil Transport (HSCT) to become part of the international air transportation system. However, before this opportunity for high speed travel can be realized, certain environmental and and economic barrier issues must be overcome. These challenges are outlined. Research activities which NASA has planned to address these barrier issues and to provide a technology base to allow U.S. manufacturers to make an informed go/no go decision on developing the HSCT are discussed.

  20. Large-scale application of highly-diluted bacteria for Leptospirosis epidemic control.

    Science.gov (United States)

    Bracho, Gustavo; Varela, Enrique; Fernández, Rolando; Ordaz, Barbara; Marzoa, Natalia; Menéndez, Jorge; García, Luis; Gilling, Esperanza; Leyva, Richard; Rufín, Reynaldo; de la Torre, Rubén; Solis, Rosa L; Batista, Niurka; Borrero, Reinier; Campa, Concepción

    2010-07-01

    Leptospirosis is a zoonotic disease of major importance in the tropics where the incidence peaks in rainy seasons. Natural disasters represent a big challenge to Leptospirosis prevention strategies especially in endemic regions. Vaccination is an effective option but of reduced effectiveness in emergency situations. Homeoprophylactic interventions might help to control epidemics by using highly-diluted pathogens to induce protection in a short time scale. We report the results of a very large-scale homeoprophylaxis (HP) intervention against Leptospirosis in a dangerous epidemic situation in three provinces of Cuba in 2007. Forecast models were used to estimate possible trends of disease incidence. A homeoprophylactic formulation was prepared from dilutions of four circulating strains of Leptospirosis. This formulation was administered orally to 2.3 million persons at high risk in an epidemic in a region affected by natural disasters. The data from surveillance were used to measure the impact of the intervention by comparing with historical trends and non-intervention regions. After the homeoprophylactic intervention a significant decrease of the disease incidence was observed in the intervention regions. No such modifications were observed in non-intervention regions. In the intervention region the incidence of Leptospirosis fell below the historic median. This observation was independent of rainfall. The homeoprophylactic approach was associated with a large reduction of disease incidence and control of the epidemic. The results suggest the use of HP as a feasible tool for epidemic control, further research is warranted. 2010 Elsevier Ltd. All rights reserved.

  1. Cancer survivorship: a new challenge in comprehensive cancer control.

    Science.gov (United States)

    Pollack, Lori A; Greer, Greta E; Rowland, Julia H; Miller, Andy; Doneski, Donna; Coughlin, Steven S; Stovall, Ellen; Ulman, Doug

    2005-10-01

    Cancer survivors are a growing population in the United States because of earlier cancer diagnosis, the aging of society, and more effective risk reduction and treatment. Concerns about the long-term physical, psychosocial, and economic effects of cancer treatment on cancer survivors and their families are increasingly being recognized and addressed by public, private, and non-profit organizations. The purpose of this paper is to discuss how survivorship fits within the framework of comprehensive cancer control. We summarize three national reports on cancer survivorship and highlight how various organizations and programs are striving to address the needs of cancer survivors through public health planning, including the challenges these groups face and the gaps in knowledge and available services. As cancer survivorship issues are being recognized, many organizations have objectives and programs to address concerns of those diagnosed with cancer. However, better coordination and dissemination may decrease overlap and increase the reach of efforts and there is limited evidence for the effectiveness and impact of these efforts.

  2. Recombinant erythropoietin and analogues: a challenge for doping control.

    Science.gov (United States)

    Pascual, J A; Belalcazar, V; de Bolos, C; Gutiérrez, R; Llop, E; Segura, J

    2004-04-01

    Erythropoietin (EPO) increases the number of circulating erythrocytes and thus muscle oxygenation. The availability of the recombinant protein (rEPO) has increased the risk of its illegal use in sports, its detection being a difficult challenge. Five different hematopoietic parameters were initially chosen as indirect markers of rEPO abuse: concentration of serum EPO, concentration of serum-soluble transferrin receptors (sTFr), hematocrit, percentage of reticulocytes, and percentage of macrocytes. New models considering only hemoglobin, serum EPO concentration, and percentage of reticulocytes are simpler and seem to be more sensitive when low doses of rEPO are used. A more direct method of urine analysis (isoelectrofocusing, double blotting, and chemiluminescent detection) based on the charge differences between rEPO and endogenous EPO, related to their carbohydrate composition, provides proof of rEPO use. Furthermore, this approach permits the detection of darbepoetin, a direct analogue of EPO also known as NESP ("new erythropoiesis stimulating protein"). Recently a protein conjugate, "synthetic erythropoiesis protein" (SEP), containing precision-length, monodisperse, negatively charged polymers instead of oligosaccharides has been synthesized. Finally, EPO-mimetics are molecules capable of acting as EPO in dimerizing the EPO receptor. Two kinds of EPO-mimetics have been described: peptides and nonpeptides. The enhancement of oxygen availability to muscles by rEPO, analogues, and mimetics constitutes one of the main challenges to doping control. Major steps have already been developed for detection ofrEPO and some analogues. In the near future, the transfection to an athlete's body of genes that code for erythropoietin might be an emerging doping issue, and sports authorities have incorporated "gene doping" among the prohibited practices.

  3. Challenges posed to the European pharmaceutical regulatory system by highly personalized medicines.

    Science.gov (United States)

    Johnston, John D; Feldschreiber, Peter

    2014-03-01

    The European pharmaceutical regulatory system has not yet been challenged by issues related to highly personalized medicines such as those to be found with active substances that affect RNA biochemistry. We review the current status of RNA-based pharmacology and present three possible case histories. The implications for the European pharmaceutical regulatory system are discussed. © 2013 The British Pharmacological Society.

  4. Synthetic Control of Kinetic Reaction Pathway and Cationic Ordering in High-Ni Layered Oxide Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dawei [Sustainable Energy Technologies Department, Brookhaven National Laboratory, Upton NY 11973 USA; Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory Physical Chemistry Solid Surfaces, Department of Chemistry, Xiamen University, Xiamen Fujian 361005 China; Kou, Ronghui [X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL 60439 USA; Ren, Yang [X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL 60439 USA; Sun, Cheng-Jun [X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL 60439 USA; Zhao, Hu [Sustainable Energy Technologies Department, Brookhaven National Laboratory, Upton NY 11973 USA; Zhang, Ming-Jian [Sustainable Energy Technologies Department, Brookhaven National Laboratory, Upton NY 11973 USA; School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen Guangdong 518055 P. R. China; Li, Yan [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne IL 60439 USA; Huq, Ashifia [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge TN 37831 USA; Ko, J. Y. Peter [The Cornell High Energy Synchrotron Source, Cornell University, Ithaca NY 14853 USA; Pan, Feng [School of Advanced Materials, Peking University Shenzhen Graduate School, Shenzhen Guangdong 518055 P. R. China; Sun, Yang-Kook [Department of Energy Engineering, Hanyang University, Seoul 133-791 South Korea; Yang, Yong [Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory Physical Chemistry Solid Surfaces, Department of Chemistry, Xiamen University, Xiamen Fujian 361005 China; Amine, Khalil [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne IL 60439 USA; Bai, Jianming [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton NY 11973 USA; Chen, Zonghai [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne IL 60439 USA; Wang, Feng [Sustainable Energy Technologies Department, Brookhaven National Laboratory, Upton NY 11973 USA

    2017-08-25

    Nickel-rich layered transition metal oxides, LiNi1-x(MnCo)(x)O-2 (1-x >= 0.5), are appealing candidates for cathodes in next-generation lithium-ion batteries (LIBs) for electric vehicles and other large-scale applications, due to their high capacity and low cost. However, synthetic control of the structural ordering in such a complex quaternary system has been a great challenge, especially in the presence of high Ni content. Herein, synthesis reactions for preparing layered LiNi0.7Mn0.15Co0.15O2 (NMC71515) by solid-state methods are investigated through a combination of time-resolved in situ high-energy X-ray diffraction and absorption spectroscopy measurements. The real-time observation reveals a strong temperature dependence of the kinetics of cationic ordering in NMC71515 as a result of thermal-driven oxidation of transition metals and lithium/oxygen loss that concomitantly occur during heat treatment. Through synthetic control of the kinetic reaction pathway, a layered NMC71515 with low cationic disordering and a high reversible capacity is prepared in air. The findings may help to pave the way for designing high-Ni layered oxide cathodes for LIBs.

  5. Adaptive Fuzzy Control for Power-Frequency Characteristic Regulation in High-RES Power Systems

    Directory of Open Access Journals (Sweden)

    Evangelos Rikos

    2017-07-01

    Full Text Available Future power systems control will require large-scale activation of reserves at distribution level. Despite their high potential, distributed energy resources (DER used for frequency control pose challenges due to unpredictability, grid bottlenecks, etc. To deal with these issues, this study presents a novel strategy of power frequency characteristic dynamic adjustment based on the imbalance state. This way, the concerned operators become aware of the imbalance location but also a more accurate redistribution of responsibilities in terms of reserves activations is achieved. The proposed control is based on the concept of “cells” which are power systems with operating capabilities and responsibilities similar to control areas (CAs, but fostering the use of resources at all voltage levels, particularly distribution grids. Control autonomy of cells allows increased RES hosting. In this study, the power frequency characteristic of a cell is adjusted in real time by means of a fuzzy controller, which curtails part of the reserves, in order to avoid unnecessary deployment throughout a synchronous area, leading to a more localised activation and reducing losses, congestions and reserves exhaustion. Simulation tests in a four-cell reference power system prove that the controller significantly reduces the use of reserves without compromising the overall stability.

  6. Integrated plasma control for high performance tokamaks

    International Nuclear Information System (INIS)

    Humphreys, D.A.; Deranian, R.D.; Ferron, J.R.; Johnson, R.D.; LaHaye, R.J.; Leuer, J.A.; Penaflor, B.G.; Walker, M.L.; Welander, A.S.; Jayakumar, R.J.; Makowski, M.A.; Khayrutdinov, R.R.

    2005-01-01

    Sustaining high performance in a tokamak requires controlling many equilibrium shape and profile characteristics simultaneously with high accuracy and reliability, while suppressing a variety of MHD instabilities. Integrated plasma control, the process of designing high-performance tokamak controllers based on validated system response models and confirming their performance in detailed simulations, provides a systematic method for achieving and ensuring good control performance. For present-day devices, this approach can greatly reduce the need for machine time traditionally dedicated to control optimization, and can allow determination of high-reliability controllers prior to ever producing the target equilibrium experimentally. A full set of tools needed for this approach has recently been completed and applied to present-day devices including DIII-D, NSTX and MAST. This approach has proven essential in the design of several next-generation devices including KSTAR, EAST, JT-60SC, and ITER. We describe the method, results of design and simulation tool development, and recent research producing novel approaches to equilibrium and MHD control in DIII-D. (author)

  7. Recruiting and retaining youth and young adults: challenges and opportunities in survey research for tobacco control.

    Science.gov (United States)

    Cantrell, Jennifer; Hair, Elizabeth C; Smith, Alexandria; Bennett, Morgane; Rath, Jessica Miller; Thomas, Randall K; Fahimi, Mansour; Dennis, J Michael; Vallone, Donna

    2018-03-01

    Evaluation studies of population-based tobacco control interventions often rely on large-scale survey data from numerous respondents across many geographic areas to provide evidence of their effectiveness. Significant challenges for survey research have emerged with the evolving communications landscape, particularly for surveying hard-to-reach populations such as youth and young adults. This study combines the comprehensive coverage of an address-based sampling (ABS) frame with the timeliness of online data collection to develop a nationally representative longitudinal cohort of young people aged 15-21. We constructed an ABS frame, partially supplemented with auxiliary data, to recruit this hard-to-reach sample. Branded and tested mail-based recruitment materials were designed to bring respondents online for screening, consent and surveying. Once enrolled, respondents completed online surveys every 6 months via computer, tablet or smartphone. Numerous strategies were utilized to enhance retention and representativeness RESULTS: Results detail sample performance, representativeness and retention rates as well as device utilization trends for survey completion among youth and young adult respondents. Panel development efforts resulted in a large, nationally representative sample with high retention rates. This study is among the first to employ this hybrid ABS-to-online methodology to recruit and retain youth and young adults in a probability-based online cohort panel. The approach is particularly valuable for conducting research among younger populations as it capitalizes on their increasing access to and comfort with digital communication. We discuss challenges and opportunities of panel recruitment and retention methods in an effort to provide valuable information for tobacco control researchers seeking to obtain representative, population-based samples of youth and young adults in the U.S. as well as across the globe. © Article author(s) (or their employer

  8. Chemistry control challenges in a supercritical water-cooled reactor

    International Nuclear Information System (INIS)

    Guzonas, David; Tremaine, Peter; Jay-Gerin, Jean-Paul

    2009-01-01

    The long-term viability of a supercritical water-cooled reactor (SCWR) will depend on the ability of designers to predict and control water chemistry to minimize corrosion and the transport of corrosion products and radionuclides. Meeting this goal requires an enhanced understanding of water chemistry as the temperature and pressure are raised beyond the critical point. A key aspect of SCWR water chemistry control will be mitigation of the effects of water radiolysis; preliminary studies suggest markedly different behavior than that predicted from simple extrapolations from conventional water-cooled reactor behavior. The commonly used strategy of adding excess hydrogen at concentrations sufficient to suppress the net radiolytic production of primary oxidizing species may not be effective in an SCWR. The behavior of low concentrations of impurities such as transition metal corrosion products, chemistry control agents, anions introduced via make-up water or from ion-exchange resins, and radionuclides (e.g., 60 Co) needs to be understood. The formation of neutral complexes increases with temperature, and can become important under near-critical and supercritical conditions; the most important region is from 300-450 C, where the properties of water change dramatically, and solvent compressibility effects exert a huge influence on solvation. The potential for increased transport and deposition of corrosion products (active and inactive), leading to (a) increased deposition on fuel cladding surfaces, and (b) increased out-of-core radiation fields and worker dose, must be assessed. There are also significant challenges associated with chemistry sampling and monitoring in an SCWR. The typical methods used in current reactor designs (grab samples, on-line monitors at the end of a cooled, depressurized sample line) will be inadequate, and in-situ measurements of key parameters will be required. This paper describes current Canadian activities in SCWR chemistry and chemistry

  9. Malaria in Brazil, Colombia, Peru and Venezuela: current challenges in malaria control and elimination.

    Science.gov (United States)

    Recht, Judith; Siqueira, André M; Monteiro, Wuelton M; Herrera, Sonia M; Herrera, Sócrates; Lacerda, Marcus V G

    2017-07-04

    In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an important public health concern in the region. Most malaria cases in South America come from Amazon rain forest areas in northern countries, where more than half of malaria is caused by Plasmodium vivax, while Plasmodium falciparum malaria incidence has decreased in recent years. This review discusses current malaria data, policies and challenges in four South American Amazon countries: Brazil, Colombia, Peru and the Bolivarian Republic of Venezuela. Challenges to continuing efforts to further decrease malaria incidence in this region include: a significant increase in malaria cases in recent years in Venezuela, evidence of submicroscopic and asymptomatic infections, peri-urban malaria, gold mining-related malaria, malaria in pregnancy, glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine use, and possible under-detection of Plasmodium malariae. Some of these challenges underscore the need to implement appropriate tools and procedures in specific regions, such as a field-compatible molecular malaria test, a P. malariae-specific test, malaria diagnosis and appropriate treatment as part of regular antenatal care visits, G6PD test before primaquine administration for P. vivax cases (with weekly primaquine regimen for G6PD deficient individuals), single low dose of primaquine for P. falciparum malaria in Colombia, and national and regional efforts to contain malaria spread in Venezuela urgently needed especially in mining areas. Joint efforts and commitment towards malaria control and elimination should be strategized based on examples of successful regional malaria fighting initiatives, such as PAMAFRO and RAVREDA/AMI.

  10. High-risk medical devices, children and the FDA: regulatory challenges facing pediatric mechanical circulatory support devices.

    Science.gov (United States)

    Almond, Christopher S D; Chen, Eric A; Berman, Michael R; Less, Joanne R; Baldwin, J Timothy; Linde-Feucht, Sarah R; Hoke, Tracey R; Pearson, Gail D; Jenkins, Kathy; Duncan, Brian W; Zuckerman, Bram D

    2007-01-01

    Pediatric mechanical circulatory support is a critical unmet need in the United States. Infant- and child-sized ventricular assist devices are currently being developed largely through federal contracts and grants through the National Heart, Lung, and Blood Institute (NHLBI). Human testing and marketing of high-risk devices for children raises epidemiologic and regulatory issues that will need to be addressed. Leaders from the US Food and Drug Administration (FDA), NHLBI, academic pediatric community, and industry convened in January 2006 for the first FDA Workshop on the Regulatory Process for Pediatric Mechanical Circulatory Support Devices. The purpose was to provide the pediatric community with an overview of the federal regulatory process for high-risk medical devices and to review the challenges specific to the development and regulation of pediatric mechanical circulatory support devices. Pediatric mechanical circulatory support present significant epidemiologic, logistic, and financial challenges to industry, federal regulators, and the pediatric community. Early interactions with the FDA, shared appreciation of challenges, and careful planning will be critical to avoid unnecessary delays in making potentially life-saving devices available for children. Collaborative efforts to address these challenges are warranted.

  11. Mechanical-plowing-based high-speed patterning on hard material via advanced-control and ultrasonic probe vibration

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhihua; Zou, Qingze, E-mail: qzzou@rci.rutgers.edu [Mechanical and Aerospace Engineering Department, Rutgers, the State University of New Jersey, Piscataway, New Jersey 08854 (United States); Tan, Jun; Jiang, Wei [Electrical and Computer Engineering Department, Rutgers, the State University of New Jersey, Piscataway, New Jersey 08854 (United States)

    2013-11-15

    In this paper, we present a high-speed direct pattern fabrication on hard materials (e.g., a tungsten-coated quartz substrate) via mechanical plowing. Compared to other probe-based nanolithography techniques based on chemical- and/or physical-reactions (e.g., the Dip-pen technique), mechanical plowing is meritorious for its low cost, ease of process control, and capability of working with a wide variety of materials beyond conductive and/or soft materials. However, direct patterning on hard material faces two daunting challenges. First, the patterning throughput is ultimately hindered by the “writing” (plowing) speed, which, in turn, is limited by the adverse effects that can be excited/induced during high-speed, and/or large-range plowing, including the vibrational dynamics of the actuation system (the piezoelectric actuator, the cantilever, and the mechanical fixture connecting the cantilever to the actuator), the dynamic cross-axis coupling between different axes of motion, and the hysteresis and the drift effects related to the piezoelectric actuators. Secondly, it is very challenging to directly pattern on ultra-hard materials via plowing. Even with a diamond probe, the line depth of the pattern via continuous plowing on ultra-hard materials such as tungsten, is still rather small (<0.5 nm), particularly when the “writing” speed becomes high. To overcome these two challenges, we propose to utilize a novel iterative learning control technique to achieve precision tracking of the desired pattern during high-speed, large-range plowing, and introduce ultrasonic vibration of the probe in the normal (vertical) direction during the plowing process to enable direct patterning on ultra hard materials. The proposed approach was implemented to directly fabricate patterns on a mask with tungsten coating and quartz substrate. The experimental results demonstrated that a large-size pattern of four grooves (20 μm in length with 300 nm spacing between lines) can be

  12. Oral food challenges in children

    Directory of Open Access Journals (Sweden)

    Hye Yung Yum

    2011-01-01

    Full Text Available Many patients assume that allergic reactions against foods are responsible for triggering or worsening their allergic symptoms. Therefore, it is important to identify patients who would benefit from an elimination diet, while avoiding unnecessary dietary restrictions. The diagnosis of food allergy depends on the thorough review of the patients's medical history, results of supplemented trials of dietary elimination, and in vivo and in vitro tests for measuring specific IgE levels. However, in some cases the reliability of such procedures is suboptimal. Oral food challenges are procedures employed for making an accurate diagnosis of immediate and occasionally delayed adverse reactions to foods. The timing and type of the challenge, preparation of patients, foods to be tested, and dosing schedule should be determined on the basis of the patient's history, age, and experience. Although double-blind, placebo-controlled food challenges(DBPCFC are used to establish definitively if a food is the cause of adverse reactions, they are time-consuming, expensive and troublesome for physician and patients. In practice, An open challenge controlled by trained personnel is sufficient especially in infants and young children. The interpretation of the results and follow-up after a challenge are also important. Since theses challenges are relatively safe and informative, controlled oral food challenges could become the measure of choice in children.

  13. High performance computing in linear control

    International Nuclear Information System (INIS)

    Datta, B.N.

    1993-01-01

    Remarkable progress has been made in both theory and applications of all important areas of control. The theory is rich and very sophisticated. Some beautiful applications of control theory are presently being made in aerospace, biomedical engineering, industrial engineering, robotics, economics, power systems, etc. Unfortunately, the same assessment of progress does not hold in general for computations in control theory. Control Theory is lagging behind other areas of science and engineering in this respect. Nowadays there is a revolution going on in the world of high performance scientific computing. Many powerful computers with vector and parallel processing have been built and have been available in recent years. These supercomputers offer very high speed in computations. Highly efficient software, based on powerful algorithms, has been developed to use on these advanced computers, and has also contributed to increased performance. While workers in many areas of science and engineering have taken great advantage of these hardware and software developments, control scientists and engineers, unfortunately, have not been able to take much advantage of these developments

  14. Health Information System Role-Based Access Control Current Security Trends and Challenges.

    Science.gov (United States)

    de Carvalho Junior, Marcelo Antonio; Bandiera-Paiva, Paulo

    2018-01-01

    This article objective is to highlight implementation characteristics, concerns, or limitations over role-based access control (RBAC) use on health information system (HIS) using industry-focused literature review of current publishing for that purpose. Based on the findings, assessment for indication of RBAC is obsolete considering HIS authorization control needs. We have selected articles related to our investigation theme "RBAC trends and limitations" in 4 different sources related to health informatics or to the engineering technical field. To do so, we have applied the following search query string: "Role-Based Access Control" OR "RBAC" AND "Health information System" OR "EHR" AND "Trends" OR "Challenges" OR "Security" OR "Authorization" OR "Attacks" OR "Permission Assignment" OR "Permission Relation" OR "Permission Mapping" OR "Constraint". We followed PRISMA applicable flow and general methodology used on software engineering for systematic review. 20 articles were selected after applying inclusion and exclusion criteria resulting contributions from 10 different countries. 17 articles advocate RBAC adaptations. The main security trends and limitations mapped were related to emergency access, grant delegation, and interdomain access control. Several publishing proposed RBAC adaptations and enhancements in order to cope current HIS use characteristics. Most of the existent RBAC studies are not related to health informatics industry though. There is no clear indication of RBAC obsolescence for HIS use.

  15. The role of the dopaminergic system in mood, motivation and cognition in Parkinson's disease: a double blind randomized placebo-controlled experimental challenge with pramipexole and methylphenidate.

    Science.gov (United States)

    Drijgers, Rosa L; Verhey, Frans R J; Tissingh, Gerrit; van Domburg, Peter H M F; Aalten, Pauline; Leentjens, Albert F G

    2012-09-15

    In Parkinson's disease (PD) reduced dopaminergic activity in the mesocorticolimbic pathway is implied in the pathophysiology of several non-motor symptoms related to mood, motivation and cognition. Insight in the pathophysiology of these syndromes may pave the way for more rational treatments. In a double-blind, randomized, placebo controlled, crossover design with three arms, we studied the effects of a direct dopaminergic challenge with the dopamine 2 receptor agonist pramipexole, an indirect challenge with the dopamine reuptake inhibitor methylphenidate, and placebo on measures of mood, motivation and cognition in 23 agonist-naïve PD patients and 23 healthy controls. Acute challenge with pramipexole had a negative effect on mood and fatigue in both patients and controls. In addition, challenge with pramipexole led to increased anger, fatigue, vigor and tension in healthy control subjects, but not in PD patients. Challenge with methylphenidate had a positive effect on anhedonia and vigor in PD patients. Due to its side effects after a single administration, pramipexole is probably less suitable for acute challenge studies. The acute effects of a methylphenidate challenge on anhedonia and vigor in PD patients make this drug an interesting choice for further studies of the treatment of mood and motivational disorders in this population. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Effect of cognitive challenge on the postural control of patients with ACL reconstruction under visual and surface perturbations.

    Science.gov (United States)

    Lion, Alexis; Gette, Paul; Meyer, Christophe; Seil, Romain; Theisen, Daniel

    2018-02-01

    Our study aimed to evaluate the effect of cognitive challenge on double-leg postural control under visual and surface perturbations of patients with anterior cruciate ligament reconstruction (ACLR) cleared to return to sport. Double-leg stance postural control of 19 rehabilitated patients with ACLR (age: 24.8 ± 6.7 years, time since surgery: 9.2 ± 1.6 months) and 21 controls (age: 24.9 ± 3.7 years) was evaluated in eight randomized situations combining two cognitive (with and without silent backward counting in steps of seven), two visual (eyes open, eyes closed) and two surface (stable support, foam support) conditions. Sway area and sway path of the centre of foot pressure were measured during three 20-s recordings for each situation. Higher values indicated poorer postural control. Generally, postural control of patients with ACLR and controls was similar for sway area and sway path (p > 0.05). The lack of visual anchorage and the disturbance of the plantar input by the foam support increased sway area and sway path (p postural control during double-leg stance tests. The use of a dual task paradigm under increased task complexity modified postural control, but in a similar way in patients with ACLR than in healthy controls. Double-leg stance tests, even under challenging conditions, are not sensitive enough to reveal postural control differences between rehabilitated patients with ACLR and controls. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The progress and challenges of implementation of the Framework Convention on Tobacco Control (WHO FCTC) in Kyrgyz Republic

    OpenAIRE

    Chinara Bekbasarova

    2018-01-01

    Background and challenges to implementation The Kyrgyz Republic is Party of the WHO FCTC since August 23, 2006. This abstract analyzes progress and challenges during 10 years of implementation of WHO´s FCTC Intervention or response National Tobacco Control (TC) Law was adopted on August 21, 2006, entered into force on December 19, 2006 and was amended and supplemented during 10 years 2 times. TC measures were included, as one of main priorities, in the National Program on Heal...

  18. The implementation of the serial trial intervention for pain and challenging behaviour in advanced dementia patients (STA OP!: a clustered randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Francke Anneke L

    2011-03-01

    Full Text Available Abstract Background Pain (physical discomfort and challenging behaviour are highly prevalent in nursing home residents with dementia: at any given time 45-80% of nursing home residents are in pain and up to 80% have challenging behaviour. In the USA Christine Kovach developed the serial trial intervention (STI and established that this protocol leads to less discomfort and fewer behavioural symptoms in moderate to severe dementia patients. The present study will provide insight into the effects of implementation of the Dutch version of the STI-protocol (STA OP! in comparison with a control intervention, not only on behavioural symptoms, but also on pain, depression, and quality of life. This article outlines the study protocol. Methods/Design The study is a cluster randomized controlled trial in 168 older people (aged >65 years with mild or moderate dementia living in nursing homes. The clusters, Dutch nursing homes, are randomly assigned to either the intervention condition (training and implementation of the STA OP!-protocol or the control condition (general training focusing on challenging behaviour and pain, but without the step-wise approach. Measurements take place at baseline, after 3 months (end of the STA OP! training period and after 6 months. Primary outcome measures are symptoms of challenging behaviour (measured with the Cohen-Mansfield Agitation Inventory (CMAI and the Neuropsychiatric Inventory-Nursing Home version (NPI-NH, and pain (measure with the Dutch version of the Pain Assessment Checklist for Seniors (PACSLAC-D and the Minimum Data Set of the Resident Assessment Instrument (MDS-RAI pain scale. Secondary outcome measures include symptoms of depression (Cornell and MDS-RAI depression scale, Quality of Live (Qualidem, changes in prescriptions of analgesics and psychotropic drugs, and the use of non-pharmacological comfort interventions (e.g. snoezelen, reminiscence therapy. Discussion The transfer from the American design to

  19. Challenges with controlling varicella in prison settings: Experience of California, 2010–2011

    Science.gov (United States)

    Leung, Jessica; Lopez, Adriana S.; Tootell, Elena; Baumrind, Nikki; Mohle-Boetani, Janet; Leistikow, Bruce; Harriman, Kathleen H.; Preas, Christopher P.; Cosentino, Giorgio; Bialek, Stephanie R.; Marin, Mona

    2015-01-01

    We describe the epidemiology of varicella in one state prison in California during 2010–2011, control measures implemented, and associated costs. Eleven varicella cases were reported, 9 associated with 2 outbreaks. One outbreak consisted of 3 cases and the second consisted of 6 cases with 2 generations of spread. Among exposed inmates serologically tested, 98% (643/656) were VZV sero-positive. The outbreaks resulted in >1,000 inmates exposed, 444 staff exposures, and >$160,000 in costs. We documented the challenges and costs associated with controlling and managing varicella in a prison setting. A screening policy for evidence of varicella immunity for incoming inmates and staff and vaccination of susceptible persons has the potential to mitigate the impact of future outbreaks and reduce resources necessary for managing cases and outbreaks. PMID:25201912

  20. Design of auto-control high-voltage control system of pulsed neutron generator

    International Nuclear Information System (INIS)

    Lv Juntao

    2008-01-01

    It is difficult to produce multiple anode controlling time sequences under different logging mode for the high-voltage control system of the conventional pulsed neutron generator. It is also difficult realize sequential control among anode high-voltage, filament power supply and target voltage to make neutron yield stable. To these problems, an auto-control high-voltage system of neutron pulsed generator was designed. It not only can achieve anode high-voltage double blast time sequences, which can measure multiple neutron blast time sequences such as Σ, activated spectrum, etc. under inelastic scattering mode, but also can realize neutron generator real-time measurement of multi-state parameters and auto-control such as target voltage pulse width modulation (PWM), filament current, anode current, etc., there by it can produce stable neutron yield and realize stable and accurate measurement of the pulsed neutron full spectral loging tool. (authors)

  1. Effects of disease severity and medication state on postural control asymmetry during challenging postural tasks in individuals with Parkinson's disease.

    Science.gov (United States)

    Barbieri, Fabio A; Polastri, Paula F; Baptista, André M; Lirani-Silva, Ellen; Simieli, Lucas; Orcioli-Silva, Diego; Beretta, Victor S; Gobbi, Lilian T B

    2016-04-01

    The aim of this study was to investigate the effects of disease severity and medication state on postural control asymmetry during challenging tasks in individuals with Parkinson's disease (PD). Nineteen people with PD and 11 neurologically healthy individuals performed three standing task conditions: bipedal standing, tandem and unipedal adapted standing; the individuals with PD performed the tasks in ON and OFF medication state. The participants with PD were distributed into 2 groups according to disease severity: unilateral group (n=8) and bilateral group (n=11). The two PD groups performed the evaluations both under and without the medication. Two force plates were used to analyze the posture. The symmetric index was calculated for various of center of pressure. ANOVA one-way (groups) and two-way (PD groups×medication), with repeated measures for medication, were calculated. For main effects of group, the bilateral group was more asymmetric than CG. For main effects of medication, only unipedal adapted standing presented effects of PD medication. There was PD groups×medication interaction. Under the effects of medication, the unilateral group presented lower asymmetry of RMS in anterior-posterior direction and area than the bilateral group in unipedal adapted standing. In addition, the unilateral group presented lower asymmetry of mean velocity, RMS in anterior-posterior direction and area in unipedal standing and area in tandem adapted standing after a medication dose. Postural control asymmetry during challenging postural tasks was dependent on disease severity and medication state in people with PD. The bilateral group presented higher postural control asymmetry than the control and unilateral groups in challenging postural tasks. Finally, the medication dose was able to reduce postural control asymmetry in the unilateral group during challenging postural tasks. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. The importance and challenges of assessing cognition in Indigenous Australians.

    Science.gov (United States)

    Dingwall, Kylie; Cairney, Sheree

    2009-08-01

    The aim of this paper was to investigate the importance and challenges involved in conducting serial cognitive assessments among healthy Indigenous adolescents. Cognitive assessments were conducted at fortnightly intervals for 2 months and again at 6 and 12 months among a group of Indigenous students from a boarding school in the Northern Territory. These students were to be the healthy control group in a long-term study of substance abuse. Recruitment and attrition rates were reviewed and related challenges for assessing participants were identified. From the recruited sample (n=49), 18% reported heavy or frequent use of alcohol, cannabis or petrol. Males were more likely to have used these substances compared to females. Attrition increased as the follow-up interval increased with 49 recruits reducing to 32 in the first 2 months and only 15 and 13 of the initial group remaining for the 6 and 12 month follow-ups respectively. Main challenges included (i) appropriateness of tests and assessment processes, (ii) high rates of substance abuse and other illness in the control group and (iii) high attrition rates. The importance of assessing cognition appropriately is highlighted by a lack of information regarding mental health issues in Indigenous populations.

  3. Challenges for maintaining the modernization of instrumentation and control systems; Desafios para el mantenimiento en la modernizacion de sistemas de instrumentacion y control

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, V.

    2014-04-01

    Instrumentation and control system upgrades in nuclear power plants come with some challenges for their maintenance staff. It is important to have a long term modernization plant that derives from specific studies for each system. Training, spares, configuration control and cybersecurity are critical topics to take into account from the beginning of these projects. New system maintenance plans can require a new approach in accordance with the technology. FPGAs (Field Programmable Gate Array) appear as the alternative for the future, mainly in safety systems. (Author)

  4. Why has the Ebola outbreak in West Africa been so challenging to control?

    Science.gov (United States)

    Semalulu, T; Wong, G; Kobinger, G; Huston, P

    2014-08-14

    West Africa is in the midst of the largest Ebola outbreak ever; there have been over 1000 deaths and many new cases are reported each day. The World Health Organization (WHO) declared it an outbreak in March 2014 and on August 6, 2014 the WHO declared the outbreak a public health emergency of international concern. Based on the number of deaths and total number of cases reported to the WHO as of August 11, 2014, the current outbreak has an overall mortality rate of 55%. Outbreak control measures against Ebola virus disease are effective. Why then, has this outbreak been so challenging to control? Ebola is transmitted through bodily fluids and immediately attacks the immune system, then progressively attacks the major organs and the lining of blood vessels. Sierra Leone, Guinea and Liberia are small countries that have limited resources to respond to prolonged outbreaks, especially in rural areas. This has been made more challenging by the fact that health care workers are at risk of contracting Ebola virus disease. Treatment to date has been supportive, not curative and outbreak control strategies have been met with distrust due to fear and misinformation. However, important progress is being made. The international response to Ebola is gaining momentum, communication strategies have been developed to address the fear and mistrust, and promising treatments are under development, including a combination of three monoclonal antibodies that has been administered to two American Ebola infected health care workers. The National Microbiology Laboratory of the Public Health Agency of Canada (PHAC) has been supporting laboratory diagnostic efforts in West Africa and PHAC has been working with the provinces and territories and key stakeholders to ensure Canada is prepared for a potential Ebola importation.

  5. Challenges of a community based pragmatic, randomised controlled trial of weight loss maintenance.

    Science.gov (United States)

    Randell, Elizabeth; McNamara, Rachel; Shaw, Christine; Espinasse, Aude; Simpson, Sharon Anne

    2015-12-18

    Randomised controlled trials (RCTs) have a reputation for being inherently difficult to deliver as planned and often face unforeseen challenges and delays, particularly in relation to organisational and governance difficulties, participant interest, constraints due to allocation of costs, local investigator interest and lengthy bureaucracy. Recruitment is often difficult and the challenges faced often impact on the cost and delivery of a successful trial within the funded period. This paper reflects upon the challenges faced in delivering a pragmatic RCT of weight loss maintenance in a community setting and suggests some potential solutions. The weight loss maintenance in adults trial aimed to evaluate the impact of a 12 month, individually tailored weight maintenance intervention on BMI 3 years from randomisation. Participants were recruited primarily from participant identification centres (PICs)-GP surgeries, exercise on referral schemes and slimming world. The intervention was delivered in community settings. A recruitment strategy implementation plan was drafted to address and monitor poor recruitment. Delays in opening and recruitment were experienced early on. Some were beyond the control of the study team such as; disagreement over allocation of national health service costs and PIC classification as well as difficulties in securing support from research networks. That the intervention was delivered in community settings was often at the root of these issues. Key items to address at the design stage of future trials include feasibility of eligibility criteria. The most effective element of the recruitment implementation plan was to refocus sources of recruitment and target only those who could fulfil the eligibility criteria immediately. Learnings from this trial should be kept in mind by those designing similar studies in the future. Considering potential governance, cost and research network support implications at the design stage of pragmatic trials of

  6. Eight challenges for network epidemic models

    Directory of Open Access Journals (Sweden)

    Lorenzo Pellis

    2015-03-01

    Full Text Available Networks offer a fertile framework for studying the spread of infection in human and animal populations. However, owing to the inherent high-dimensionality of networks themselves, modelling transmission through networks is mathematically and computationally challenging. Even the simplest network epidemic models present unanswered questions. Attempts to improve the practical usefulness of network models by including realistic features of contact networks and of host–pathogen biology (e.g. waning immunity have made some progress, but robust analytical results remain scarce. A more general theory is needed to understand the impact of network structure on the dynamics and control of infection. Here we identify a set of challenges that provide scope for active research in the field of network epidemic models.

  7. Communication, control and security challenges for the smart grid

    CERN Document Server

    Muyeen, SM

    2017-01-01

    The Smart Grid is a modern electricity grid allowing for distributed, renewable intermittent generation, partly owned by consumers. This requires advanced control and communication technologies in order to provide high quality power supply and secure generation, transmission and distribution. This book outlines these emerging technologies.

  8. An early feeding regime and a high-density amino acid diet on growth performance of broilers under subclinical necrotic enteritis challenge

    OpenAIRE

    Chake Keerqin; Shu-Biao Wu; Birger Svihus; Robert Swick; Natalie Morgan; Mingan Choct

    2017-01-01

    Broilers that have early access to feed have been shown to have enhanced immune system and gut development and heightened resilience against necrotic enteritis (NE). This study examined the effect of early feeding a high amino acid density diet on performance of broilers under a sub-clinical NE challenge model. Ross 308 broilers (n = 576) were assigned to a 2 × 2 × 2 factorial design with 2 feeding regimes (feed access either within 6 h post-hatch or after 48 h post-hatch), 2 diets (control d...

  9. Cancer prevention and control: alarming challenges in China.

    Science.gov (United States)

    Bode, Ann M; Dong, Zigang; Wang, Hongyang

    2016-03-01

    China is geographically the third largest country in the world and the most populated low-to-middle-income country. Cancer incidence and mortality rates for some cancers in the USA and European countries have steadily decreased over the last decades, whereas the incidence and mortality of certain cancers in China have been increasing at an alarming speed. Rapid industrialization and urbanization in China have been accompanied by incredible changes in lifestyle and environment combined with an aging population. Mortality caused by lung, colorectal and breast cancers has been steadily increasing, whereas cancer mortality from gastric, esophageal and cervical tumors has tended to decrease. Similar to what has occurred in the United States, unhealthy lifestyles in China, including heavy smoking and poor diet combined with pollution, have contributed to increased cancer risk. China is facing many challenges in cancer treatment and prevention for the general population. The major areas that need to be addressed in the control of cancer in China include cancers associated with environmental pollution, tobacco use, occupational carcinogens, infection, excessive alcohol consumption, dietary deficiencies and obesity. In this perspective, we review the problems in each area and suggest ideas for future directions in cancer research and strategies and actions to reduce the incidence of cancer in China.

  10. Mobile Device-Based Electronic Data Capture System Used in a Clinical Randomized Controlled Trial: Advantages and Challenges.

    Science.gov (United States)

    Zhang, Jing; Sun, Lei; Liu, Yu; Wang, Hongyi; Sun, Ningling; Zhang, Puhong

    2017-03-08

    Electronic data capture (EDC) systems have been widely used in clinical research, but mobile device-based electronic data capture (mEDC) system has not been well evaluated. The aim of our study was to evaluate the feasibility, advantages, and challenges of mEDC in data collection, project management, and telemonitoring in a randomized controlled trial (RCT). We developed an mEDC to support an RCT called "Telmisartan and Hydrochlorothiazide Antihypertensive Treatment (THAT)" study, which was a multicenter, double-blinded, RCT, with the purpose of comparing the efficacy of telmisartan and hydrochlorothiazide (HCTZ) monotherapy in high-sodium-intake patients with mild to moderate hypertension during a 60 days follow-up. Semistructured interviews were conducted during and after the trial to evaluate the feasibility, advantage, and challenge of mEDC. Nvivo version 9.0 (QSR International) was used to analyze records of interviews, and a thematic framework method was used to obtain outcomes. The mEDC was successfully used to support the data collection and project management in all the 14 study hospitals. A total of 1333 patients were recruited with support of mEDC, of whom 1037 successfully completed all 4 visits. Across all visits, the average time needed for 141 questions per patient was 53 min, which were acceptable to both doctors and patients. All the interviewees, including 24 doctors, 53 patients, 1 clinical research associate (CRA), 1 project manager (PM), and 1 data manager (DM), expressed their satisfaction to nearly all the functions of the innovative mEDC in randomization, data collection, project management, quality control, and remote monitoring in real time. The average satisfaction score was 9.2 (scale, 0-10). The biggest challenge came from the stability of the mobile or Wi-Fi signal although it was not a problem in THAT study. The innovative mEDC has many merits and is well acceptable in supporting data collection and project management in a timely

  11. Anaesthetic Challenges in a High Risk Parturient with Myasthenia ...

    African Journals Online (AJOL)

    The prevalence of myasthenia gravis is low. The management implications of this disease in pregnant women are very challenging for anaesthetists. The objective is to highlight some of the challenges, the management and the lessons learnt during the management of this patient. This is a case report of a 31-year old ...

  12. Interaction design challenges and solutions for ALMA operations monitoring and control

    Science.gov (United States)

    Pietriga, Emmanuel; Cubaud, Pierre; Schwarz, Joseph; Primet, Romain; Schilling, Marcus; Barkats, Denis; Barrios, Emilio; Vila Vilaro, Baltasar

    2012-09-01

    The ALMA radio-telescope, currently under construction in northern Chile, is a very advanced instrument that presents numerous challenges. From a software perspective, one critical issue is the design of graphical user interfaces for operations monitoring and control that scale to the complexity of the system and to the massive amounts of data users are faced with. Early experience operating the telescope with only a few antennas has shown that conventional user interface technologies are not adequate in this context. They consume too much screen real-estate, require many unnecessary interactions to access relevant information, and fail to provide operators and astronomers with a clear mental map of the instrument. They increase extraneous cognitive load, impeding tasks that call for quick diagnosis and action. To address this challenge, the ALMA software division adopted a user-centered design approach. For the last two years, astronomers, operators, software engineers and human-computer interaction researchers have been involved in participatory design workshops, with the aim of designing better user interfaces based on state-of-the-art visualization techniques. This paper describes the process that led to the development of those interface components and to a proposal for the science and operations console setup: brainstorming sessions, rapid prototyping, joint implementation work involving software engineers and human-computer interaction researchers, feedback collection from a broader range of users, further iterations and testing.

  13. Increased alertness, better than posture prioritization, explains dual-task performance in prosthesis users and controls under increasing postural and cognitive challenge.

    Science.gov (United States)

    Howard, Charla L; Perry, Bonnie; Chow, John W; Wallace, Chris; Stokic, Dobrivoje S

    2017-11-01

    Sensorimotor impairments after limb amputation impose a threat to stability. Commonly described strategies for maintaining stability are the posture first strategy (prioritization of balance) and posture second strategy (prioritization of concurrent tasks). The existence of these strategies was examined in 13 below-knee prosthesis users and 15 controls during dual-task standing under increasing postural and cognitive challenge by evaluating path length, 95% sway area, and anterior-posterior and medial-lateral amplitudes of the center of pressure. The subjects stood on two force platforms under usual (hard surface/eyes open) and difficult (soft surface/eyes closed) conditions, first alone and while performing a cognitive task without and then with instruction on cognitive prioritization. During standing alone, sway was not significantly different between groups. After adding the cognitive task without prioritization instruction, prosthesis users increased sway more under the dual-task than single-task standing (p ≤ 0.028) during both usual and difficult conditions, favoring the posture second strategy. Controls, however, reduced dual-task sway under a greater postural challenge (p ≤ 0.017), suggesting the posture first strategy. With prioritization of the cognitive task, sway was unchanged or reduced in prosthesis users, suggesting departure from the posture second strategy, whereas controls maintained the posture first strategy. Individual analysis of dual tasking revealed that greater postural demand in controls and greater cognitive challenge in prosthesis users led to both reduced sway and improved cognitive performance, suggesting cognitive-motor facilitation. Thus, activation of additional resources through increased alertness, rather than posture prioritization, may explain dual-task performance in both prosthesis users and controls under increasing postural and cognitive challenge.

  14. International network connectivity and performance -- The challenge from high energy physics

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, W.

    2000-03-20

    The requirements of the new generation of High Energy and Nuclear Physics (HENP) experiments such as the BaBar detector at the Stanford Linear Accelerator Center (SLAC), the Relativistic Heavy Ion Collider (RHIC) groups at the Brookhaven National Laboratory (BNL) and the LHC projects currently under development at the European Center for Particle Physics (CERN) are a huge challenge to networking. In order to increase understanding and to improve performance and connectivity by identifying bottlenecks and allocating resources, the HENP networking community has been actively monitoring the network for over five years.

  15. Engineering challenges of BioNEMS: the integration of microfluidics, micro- and nanodevices, models and external control for systems biology.

    Science.gov (United States)

    Wikswo, J P; Prokop, A; Baudenbacher, F; Cliffel, D; Csukas, B; Velkovsky, M

    2006-08-01

    Systems biology, i.e. quantitative, postgenomic, postproteomic, dynamic, multiscale physiology, addresses in an integrative, quantitative manner the shockwave of genetic and proteomic information using computer models that may eventually have 10(6) dynamic variables with non-linear interactions. Historically, single biological measurements are made over minutes, suggesting the challenge of specifying 10(6) model parameters. Except for fluorescence and micro-electrode recordings, most cellular measurements have inadequate bandwidth to discern the time course of critical intracellular biochemical events. Micro-array expression profiles of thousands of genes cannot determine quantitative dynamic cellular signalling and metabolic variables. Major gaps must be bridged between the computational vision and experimental reality. The analysis of cellular signalling dynamics and control requires, first, micro- and nano-instruments that measure simultaneously multiple extracellular and intracellular variables with sufficient bandwidth; secondly, the ability to open existing internal control and signalling loops; thirdly, external BioMEMS micro-actuators that provide high bandwidth feedback and externally addressable intracellular nano-actuators; and, fourthly, real-time, closed-loop, single-cell control algorithms. The unravelling of the nested and coupled nature of cellular control loops requires simultaneous recording of multiple single-cell signatures. Externally controlled nano-actuators, needed to effect changes in the biochemical, mechanical and electrical environment both outside and inside the cell, will provide a major impetus for nanoscience.

  16. Effectiveness of the 'Who's Challenging Who' support staff training intervention to improve attitudes and empathy towards adults with intellectual disability and challenging behaviours: study protocol for a cluster randomised controlled trial.

    Science.gov (United States)

    Randell, Elizabeth; Hastings, Richard P; McNamara, Rachel; Knight, Roseanna; Gillespie, David; Taylor, Zachary

    2017-10-05

    Findings suggest approximately one in six people with intellectual disability engage in 'challenging behaviours', which include aggression towards others/property and self-injurious actions. In residential settings, actions of staff members can make challenging behaviours more likely to occur, or make these behaviours worse. In particular, negative attitudes from members of staff and lack of understanding about the reasons for challenging behaviour are contributory factors. 'Who's Challenging Who?' (WCW) training is designed to emphasise the role of staff in residential settings as a challenge also to people with intellectual disability. The course is delivered jointly by a trainer with intellectual disability who has been labelled as having challenging behaviour, along with a trainer without intellectual disability. This is a cluster randomised two-arm trial of WCW training versus a waiting list control. Overall, 118 residential settings will be recruited and randomised on a 1:1 ratio. Within each setting, two members of staff will be invited to take part in the trial. Participants will complete assessments at baseline and at 6 and 20 weeks. WCW is a half day initial training course with some follow-on coaching to ensure implementation. The primary outcome is changes in staff empathy towards people with challenging behaviour. Secondary outcomes at the staff level include confidence, attitudes and work-related well-being. Secondary outcomes at the residential setting level include recorded incidents of aggressive challenging behaviour, and use of any restrictive practices. If the results of the cluster randomised trial are positive, we will disseminate the findings widely and make all training manuals and materials freely available for anyone in intellectual disability services (and beyond) to use. Our training approach may have wider implications in other areas of social care. It may also provide a generally applicable model for how to train people with

  17. Highly reliable electro-hydraulic control system

    International Nuclear Information System (INIS)

    Mande, Morima; Hiyama, Hiroshi; Takahashi, Makoto

    1984-01-01

    The unscheduled shutdown of nuclear power stations disturbs power system, and exerts large influence on power generation cost due to the lowering of capacity ratio; therefore, high reliability is required for the control system of nuclear power stations. Toshiba Corp. has exerted effort to improve the reliability of the control system of power stations, and in this report, the electro-hydraulic control system for the turbines of nuclear power stations is described. The main functions of the electro-hydraulic control system are the control of main steam pressure with steam regulation valves and turbine bypass valves, the control of turbine speed and load, the prevention of turbine overspeed, the protection of turbines and so on. The system is composed of pressure sensors and a speed sensor, the control board containing the electronic circuits for control computation and protective sequence, the oil cylinders, servo valves and opening detectors of the valves for control, a high pressure oil hydraulic machine and piping, the operating panel and so on. The main features are the adoption of tripling intermediate value selection method, the multiplying of protection sensors and the adoption of 2 out of 3 trip logic, the multiplying of power sources, the improvement of the reliability of electronic circuit hardware and oil hydraulic system. (Kako, I.)

  18. Challenges with controlling varicella in prison settings: experience of California, 2010 to 2011.

    Science.gov (United States)

    Leung, Jessica; Lopez, Adriana S; Tootell, Elena; Baumrind, Nikki; Mohle-Boetani, Janet; Leistikow, Bruce; Harriman, Kathleen H; Preas, Christopher P; Cosentino, Giorgio; Bialek, Stephanie R; Marin, Mona

    2014-10-01

    This article describes the epidemiology of varicella in one state prison in California during 2010 and 2011, control measures implemented, and associated costs. Eleven varicella cases were reported, of which nine were associated with two outbreaks. One outbreak consisted of three cases and the second consisted of six cases with two generations of spread. Among exposed inmates serologically tested, 98% (643/656) were varicella-zoster virus seropositive. The outbreaks resulted in > 1,000 inmates exposed, 444 staff exposures, and > $160,000 in costs. The authors documented the challenges and costs associated with controlling and managing varicella in a prison setting. A screening policy for evidence of varicella immunity for incoming inmates and staff and vaccination of susceptible persons has the potential to mitigate the impact of future outbreaks and reduce resources necessary to manage cases and outbreaks. © The Author(s) 2014.

  19. Aeronautical telecommunications network advances, challenges, and modeling

    CERN Document Server

    Musa, Sarhan M

    2015-01-01

    Addresses the Challenges of Modern-Day Air Traffic Air traffic control (ATC) directs aircraft in the sky and on the ground to safety, while the Aeronautical Telecommunications Network (ATN) comprises all systems and phases that assist in aircraft departure and landing. The Aeronautical Telecommunications Network: Advances, Challenges, and Modeling focuses on the development of ATN and examines the role of the various systems that link aircraft with the ground. The book places special emphasis on ATC-introducing the modern ATC system from the perspective of the user and the developer-and provides a thorough understanding of the operating mechanism of the ATC system. It discusses the evolution of ATC, explaining its structure and how it works; includes design examples; and describes all subsystems of the ATC system. In addition, the book covers relevant tools, techniques, protocols, and architectures in ATN, including MIPv6, air traffic control (ATC), security of air traffic management (ATM), very-high-frequenc...

  20. The control of nuclear proliferation: future challenges. Swedish Institute of International Affairs, Stockholm, 23 April 1998

    International Nuclear Information System (INIS)

    ElBaradei, M.

    1998-01-01

    The document reproduces the text of the conference given by the Director General of the IAEA at the Swedish Institute of International Affairs in Stockholm on 23 April 1998. After a short presentation of the Agency's current verification activities, particularly in Iraq and Democratic People's Republic of Korea, the Director General focuses on the present and future role of the IAEA in the control of nuclear proliferation through its strengthened safeguards system, in the prevention of nuclear terrorism, and future challenges of controlling nuclear proliferation from both political and technical point of view

  1. Infection control challenges in deployed US military treatment facilities.

    Science.gov (United States)

    Hospenthal, Duane R; Crouch, Helen K

    2009-04-01

    Personnel sustaining combat-related injuries in current overseas conflicts continue to have their care complicated by infections caused by multidrug-resistant organisms, including Acinetobacter, Klebsiella, and Pseudomonas. Although presumed to be due to multiple factors both within and outside of the combat theater, concern has been raised about the difficulties in establishing and maintaining standard infection control (IC) practices in deployed medical treatment facilities and in the evacuation of the injured back to the United States. Level III facilities (hospitals capable of holding patients >72 hours) in Iraq and Afghanistan and the evacuation system from Iraq to the continental US were reviewed by an expert IC-infectious disease team. All reviewed facilities had established IC programs, but these were staffed by personnel with limited IC experience, often without perceived adequate time dedicated to perform their duties, and without uniform levels of command emphasis or support. Proper hand hygiene between patients was not always ideal. Isolation and cohorting of patients to decrease multidrug-resistant organism colonization and infection varied among facilities. Review of standard operating procedures found variability among institutions and in quality of these documents. Application of US national and theater-specific guidelines and of antimicrobial control measures also varied among facilities. Effective IC practices are often difficult to maintain in modern US hospitals. In the deployed setting, with ever-changing personnel in a less than optimal practice environment, IC is even more challenging. Standardization of practice with emphasis on the basics of IC practice (e.g., hand hygiene and isolation procedures) needs to be emplaced and maintained in the deployed setting.

  2. Photonic integrated circuits: new challenges for lithography

    Science.gov (United States)

    Bolten, Jens; Wahlbrink, Thorsten; Prinzen, Andreas; Porschatis, Caroline; Lerch, Holger; Giesecke, Anna Lena

    2016-10-01

    In this work routes towards the fabrication of photonic integrated circuits (PICs) and the challenges their fabrication poses on lithography, such as large differences in feature dimension of adjacent device features, non-Manhattan-type features, high aspect ratios and significant topographic steps as well as tight lithographic requirements with respect to critical dimension control, line edge roughness and other key figures of merit not only for very small but also for relatively large features, are highlighted. Several ways those challenges are faced in today's low-volume fabrication of PICs, including the concept multi project wafer runs and mix and match approaches, are presented and possible paths towards a real market uptake of PICs are discussed.

  3. Attracted to power: challenge/threat and promotion/prevention focus differentially predict the attractiveness of group power

    Science.gov (United States)

    Scholl, Annika; Sassenrath, Claudia; Sassenberg, Kai

    2015-01-01

    Depending on their motivation, individuals prefer different group contexts for social interactions. The present research sought to provide more insight into this relationship. More specifically, we tested how challenge/threat and a promotion/prevention focus predict attraction to groups with high- or low-power. As such, we examined differential outcomes of threat and prevention focus as well as challenge and promotion focus that have often been regarded as closely related. According to regulatory focus, individuals should prefer groups that they expect to “feel right” for them to join: Low-power groups should be more attractive in a prevention (than a promotion) focus, as these groups suggest security-oriented strategies, which fit a prevention focus. High-power groups should be more attractive in a promotion (rather than a prevention) focus, as these groups are associated with promotion strategies fitting a promotion focus (Sassenberg et al., 2007). In contrast, under threat (vs. challenge), groups that allow individuals to restore their (perceived) lack of control should be preferred: Low-power groups should be less attractive under threat (than challenge) because they provide low resources which threatened individuals already perceive as insufficient and high-power groups might be more attractive under threat (than under challenge), because their high resources allow individuals to restore control. Two experiments (N = 140) supported these predictions. The attractiveness of a group often depends on the motivation to engage in what fits (i.e., prefer a group that feels right in the light of one’s regulatory focus). However, under threat the striving to restore control (i.e., prefer a group allowing them to change the status quo under threat vs. challenge) overrides the fit effect, which may in turn guide individuals’ behavior in social interactions. PMID:25904887

  4. Preparing Secondary Stem Teachers for High-Need Schools: Challenges of an Urban Residency Program

    Science.gov (United States)

    Garza, Rubén; Duchaine, Ellen L.; Reynosa, Raymond

    2013-01-01

    Teaching residency programs that blend coursework with clinical experiences have emerged nationwide to prepare aspiring teachers for the demanding reality of teaching in high-need urban schools. The Teaching Residency Program for Critical Shortage Areas was created to help urban school districts with the challenge of recruiting and retaining…

  5. Neutron Imaging Control Report: FY 2016

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, D. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-11-30

    During the 2016 fiscal year, work began on the supervision and control systems for the neutron source currently under construction in the B194 accelerator caves. This source relies on a deuteron beam colliding with a high-speed stream of deuterium gas to create neutrons, which poses significant technical challenges. To help overcome those challenges, an integrated, operator-focused control architecture is required to collect and assimilate disparate data from a variety of measurement points, as well as provide the means to remotely control the system hardware.

  6. Taking Action on Air Pollution Control in the Beijing-Tianjin-Hebei (BTH) Region: Progress, Challenges and Opportunities

    Science.gov (United States)

    Wang, Li; Zhang, Fengying; Pilot, Eva; Yu, Jie; Holdaway, Jennifer; Yang, Linsheng; Li, Yonghua; Wang, Wuyi; Vardoulakis, Sotiris; Krafft, Thomas

    2018-01-01

    Due to rapid urbanization, industrialization and motorization, a large number of Chinese cities are affected by heavy air pollution. In order to explore progress, remaining challenges, and sustainability of air pollution control in the Beijing-Tianjin-Hebei (BTH) region after 2013, a mixed method analysis was undertaken. The quantitative analysis comprised an overview of air quality management in the BTH region. Semi-structured expert interviews were conducted with 12 stakeholders from various levels of government and research institutions who played substantial roles either in decision-making or in research and advising on air pollution control in the BTH region. The results indicated that with the stringent air pollution control policies, the air quality in BTH meets the targets of the Air Pollution Prevention and Control Action Plan. However, improvements vary across the region and for different pollutants. Although implementation has been decisive and was at least in parts effectively enforced, significant challenges remained with regard to industrial and traffic emission control, and national air quality limits continued to be significantly exceeded and competing development interests remained mainly unsolved. There were also concerns about the sustainability of the current air pollution control measures especially for industries due to the top-down enforcement, and the associated large burden of social cost including unemployment and social inequity resulting industrial restructuring. Better mechanisms for ensuring cross-sectoral coordination and for improved central-local government communication were suggested. Further suggestions were provided to improve the conceptual design and effective implementation of respective air pollution control strategies in BTH. Our study highlights some of the major hurdles that need to be addressed to succeed with a comprehensive air pollution control management for the Chinese mega-urban agglomerations. PMID:29425189

  7. Taking Action on Air Pollution Control in the Beijing-Tianjin-Hebei (BTH) Region: Progress, Challenges and Opportunities.

    Science.gov (United States)

    Wang, Li; Zhang, Fengying; Pilot, Eva; Yu, Jie; Nie, Chengjing; Holdaway, Jennifer; Yang, Linsheng; Li, Yonghua; Wang, Wuyi; Vardoulakis, Sotiris; Krafft, Thomas

    2018-02-09

    Due to rapid urbanization, industrialization and motorization, a large number of Chinese cities are affected by heavy air pollution. In order to explore progress, remaining challenges, and sustainability of air pollution control in the Beijing-Tianjin-Hebei (BTH) region after 2013, a mixed method analysis was undertaken. The quantitative analysis comprised an overview of air quality management in the BTH region. Semi-structured expert interviews were conducted with 12 stakeholders from various levels of government and research institutions who played substantial roles either in decision-making or in research and advising on air pollution control in the BTH region. The results indicated that with the stringent air pollution control policies, the air quality in BTH meets the targets of the Air Pollution Prevention and Control Action Plan. However, improvements vary across the region and for different pollutants. Although implementation has been decisive and was at least in parts effectively enforced, significant challenges remained with regard to industrial and traffic emission control, and national air quality limits continued to be significantly exceeded and competing development interests remained mainly unsolved. There were also concerns about the sustainability of the current air pollution control measures especially for industries due to the top-down enforcement, and the associated large burden of social cost including unemployment and social inequity resulting industrial restructuring. Better mechanisms for ensuring cross-sectoral coordination and for improved central-local government communication were suggested. Further suggestions were provided to improve the conceptual design and effective implementation of respective air pollution control strategies in BTH. Our study highlights some of the major hurdles that need to be addressed to succeed with a comprehensive air pollution control management for the Chinese mega-urban agglomerations.

  8. Taking Action on Air Pollution Control in the Beijing-Tianjin-Hebei (BTH Region: Progress, Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Li Wang

    2018-02-01

    Full Text Available Due to rapid urbanization, industrialization and motorization, a large number of Chinese cities are affected by heavy air pollution. In order to explore progress, remaining challenges, and sustainability of air pollution control in the Beijing-Tianjin-Hebei (BTH region after 2013, a mixed method analysis was undertaken. The quantitative analysis comprised an overview of air quality management in the BTH region. Semi-structured expert interviews were conducted with 12 stakeholders from various levels of government and research institutions who played substantial roles either in decision-making or in research and advising on air pollution control in the BTH region. The results indicated that with the stringent air pollution control policies, the air quality in BTH meets the targets of the Air Pollution Prevention and Control Action Plan. However, improvements vary across the region and for different pollutants. Although implementation has been decisive and was at least in parts effectively enforced, significant challenges remained with regard to industrial and traffic emission control, and national air quality limits continued to be significantly exceeded and competing development interests remained mainly unsolved. There were also concerns about the sustainability of the current air pollution control measures especially for industries due to the top-down enforcement, and the associated large burden of social cost including unemployment and social inequity resulting industrial restructuring. Better mechanisms for ensuring cross-sectoral coordination and for improved central-local government communication were suggested. Further suggestions were provided to improve the conceptual design and effective implementation of respective air pollution control strategies in BTH. Our study highlights some of the major hurdles that need to be addressed to succeed with a comprehensive air pollution control management for the Chinese mega-urban agglomerations.

  9. Vibrotactile Feedback Alters Dynamics Of Static Postural Control In Persons With Parkinson's Disease But Not Older Adults At High Fall Risk.

    Science.gov (United States)

    High, Carleigh M; McHugh, Hannah F; Mills, Stephen C; Amano, Shinichi; Freund, Jane E; Vallabhajosula, Srikant

    2018-06-01

    Aging and Parkinson's disease are often associated with impaired postural control. Providing extrinsic feedback via vibrotactile sensation could supplement intrinsic feedback to maintain postural control. We investigated the postural control response to vibrotactile feedback provided at the trunk during challenging stance conditions in older adults at high fall risk and individuals with Parkinson's disease compared to healthy older adults. Nine older adults at high fall risk, 9 persons with Parkinson's disease and 10 healthy older adults performed 30s quiet standing on a force platform under five challenging stance conditions with eyes open/closed and standing on firm/foam surface with feet together, each with and without vibrotactile feedback. During vibrotactile feedback trials, feedback was provided when participants swayed >10% over the center of their base of support. Participants were instructed vibrations would be in response to their movement. Magnitude of postural sway was estimated using center of pressure path length, velocity, and sway area. Dynamics of individuals' postural control was evaluated using detrended fluctuation analysis. Results showed that vibrotactile feedback induced a change in postural control dynamics among persons with Parkinson's disease when standing with intact intrinsic visual input and altered intrinsic somatosensory input, but there was no change in sway magnitude. However, use of vibrotactile feedback did not significantly alter dynamics of postural control in older adults with high risk of falling or reduce the magnitude of sway. Considering the effects of vibrotactile feedback were dependent on the population and stance condition, designing an optimal therapeutic regimen for balance training should be carefully considered and be specific to a target population. Furthermore, our results suggest that explicit instructions on how to respond to the vibrotactile feedback could affect training outcome. Copyright © 2018 The

  10. Optical control system for high-voltage terminals

    International Nuclear Information System (INIS)

    Bicek, J.J.

    1978-01-01

    An optical control system for the control of devices in the terminal of an electrostatic accelerator includes a laser that is modulated by a series of preselected codes produced by an encoder. A photodiode receiver is placed in the laser beam at the high-voltage terminal of an electrostatic accelerator. A decoder connected to the photodiode decodes the signals to provide control impulses for a plurality of devices at the high voltage of the terminal

  11. Challenges and Strategies for Prevention of Multidrug-Resistant Organism Transmission in Nursing Homes.

    Science.gov (United States)

    Dumyati, Ghinwa; Stone, Nimalie D; Nace, David A; Crnich, Christopher J; Jump, Robin L P

    2017-04-01

    Nursing home residents are at high risk for colonization and infection with bacterial pathogens that are multidrug-resistant organisms (MDROs). We discuss challenges and potential solutions to support implementing effective infection prevention and control practices in nursing homes. Challenges include a paucity of evidence that addresses MDRO transmission during the care of nursing home residents, limited staff resources in nursing homes, insufficient infection prevention education in nursing homes, and perceptions by nursing home staff that isolation and contact precautions negatively influence the well being of their residents. A small number of studies provide evidence that specifically address these challenges. Their outcomes support a paradigm shift that moves infection prevention and control practices away from a pathogen-specific approach and toward one that focuses on resident risk factors.

  12. Identification of hazelnut major allergens in sensitive patients with positive double-blind, placebo-controlled food challenge results

    DEFF Research Database (Denmark)

    Pastorello, Elide A; Vieths, Stefan; Pravettoni, Valerio

    2002-01-01

    The hazelnut major allergens identified to date are an 18-kd protein homologous to Bet v 1 and a 14-kd allergen homologous to Bet v 2. No studies have reported hazelnut allergens recognized in patients with positive double-blind, placebo-controlled food challenge (DBPCFC) results or in patients...

  13. Validation of novel recipes for double-blind, placebo-controlled food challenges in children and adults.

    Science.gov (United States)

    Vlieg-Boerstra, B J; Herpertz, I; Pasker, L; van der Heide, S; Kukler, J; Jansink, C; Vaessen, W; Beusekamp, B J; Dubois, A E J

    2011-07-01

    In double-blind, placebo-controlled food challenges (DBPCFCs), the use of challenge materials in which blinding is validated is a prerequisite for obtaining true blinded conditions during the test procedure. Therefore, the aim of this study was to enlarge the available range of validated recipes for DBPCFCs to facilitate oral challenge tests in all age groups, including young children, while maximizing the top dose in an acceptable volume. Recipes were developed and subsequently validated by a panel recruited by a matching sensory test. The best 30% of candidates were selected to participate in sensory testing using the paired comparison test. For young children, three recipes with cow's milk and one recipe with peanut could be validated which may be utilized in DBPCFCs. For children older than 4 years and adults, one recipe with egg, two with peanut, one with hazelnut, and one with cashew nut were validated for use in DBPCFCs. All recipes contained larger amounts of allergenic foods than previously validated. These recipes increase the range of validated recipes for use in DBPCFCs in adults and children. © 2011 John Wiley & Sons A/S.

  14. Data Collaboration in New York City: The Challenges of Linking High School and Post-Secondary Data

    Science.gov (United States)

    Wilkes, Shani; Brohawn, Kathryn; Mevs, Pascale; Lee, Jaein

    2012-01-01

    Education leaders across the country confront a growing challenge: too many students are not college ready when they leave high school. Although indicators exist to identify students at risk of dropping out of high school, few indicators of students' college readiness are currently in place, and few districts have linked indicators to practices…

  15. High Risk Aortic Valve Replacement - The Challenges of Multiple Treatment Strategies with an Evolving Technology.

    Science.gov (United States)

    Booth, K; Beattie, R; McBride, M; Manoharan, G; Spence, M; Jones, J M

    2016-01-01

    Deciding on the optimal treatment strategy for high risk aortic valve replacement is challenging. Transcatheter Aortic Valve implantation (TAVI) has been available in our centre as an alternative treatment modality for patients since 2008. We present our early experience of TAVI and SAVR (surgical Aortic Valve Replacement) in high risk patients who required SAVR because TAVI could not be performed. The database for Surgical aortic valve and Transcatheter aortic valve replacement referrals was interrogated to identify relevant patients. Survival to hospital discharge was 95.5% in the forty five patients who had SAVR when TAVI was deemed technically unsuitable. One year survival was 86%. Defining who is appropriate for TAVI or high risk SAVR is challenging and multidisciplinary team discussion has never been more prudent in this field of evolving technology with ever decreasing risks of surgery. The introduction of TAVI at our institution has seen a rise in our surgical caseload by approximately by 25%. Overall, the option of aortic valve intervention is being offered to more patients in general which is a substantial benefit in the treatment of aortic valve disease.

  16. Operational scale entomological intervention for malaria control: strategies, achievements and challenges in Zambia

    Directory of Open Access Journals (Sweden)

    Chanda Emmanuel

    2013-01-01

    Full Text Available Abstract Background While consensus on malaria vector control policy and strategy has stimulated unprecedented political-will, backed by international funding organizations and donors, vector control interventions are expansively being implemented based on assumptions with unequaled successes. This manuscript reports on the strategies, achievements and challenges of the past and contemporary malaria vector control efforts in Zambia. Case description All available information and accessible archived documentary records on malaria vector control in Zambia were reviewed. Retrospective analysis of routine surveillance data from the Health Management Information System (HMIS, data from population-based household surveys and various operations research reports was conducted to assess the status in implementing policies and strategies. Discussion and evaluation Empirical evidence is critical for informing policy decisions and tailoring interventions to local settings. Thus, the World Health Organization (WHO encourages the adoption of the integrated vector management (IVM strategy which is a rational decision making process for optimal use of available resources. One of the key features of IVM is capacity building at the operational level to plan, implement, monitor and evaluate vector control and its epidemiological and entomological impact. In Zambia, great progress has been made in implementing WHO-recommended vector control policies and strategies within the context of the IVM Global Strategic framework with strong adherence to its five key attributes. Conclusions The country has solid, consistent and coordinated policies, strategies and guidelines for malaria vector control. The Zambian experience demonstrates the significance of a coordinated multi-pronged IVM approach effectively operationalized within the context of a national health system.

  17. The Challenging Experience Questionnaire: Characterization of challenging experiences with psilocybin mushrooms.

    Science.gov (United States)

    Barrett, Frederick S; Bradstreet, Matthew P; Leoutsakos, Jeannie-Marie S; Johnson, Matthew W; Griffiths, Roland R

    2016-12-01

    Acute adverse psychological reactions to classic hallucinogens ("bad trips" or "challenging experiences"), while usually benign with proper screening, preparation, and support in controlled settings, remain a safety concern in uncontrolled settings (such as illicit use contexts). Anecdotal and case reports suggest potential adverse acute symptoms including affective (panic, depressed mood), cognitive (confusion, feelings of losing sanity), and somatic (nausea, heart palpitation) symptoms. Responses to items from several hallucinogen-sensitive questionnaires (Hallucinogen Rating Scale, the States of Consciousness Questionnaire, and the Five-Dimensional Altered States of Consciousness questionnaire) in an Internet survey of challenging experiences with the classic hallucinogen psilocybin were used to construct and validate a Challenging Experience Questionnaire. The stand-alone Challenging Experience Questionnaire was then validated in a separate sample. Seven Challenging Experience Questionnaire factors (grief, fear, death, insanity, isolation, physical distress, and paranoia) provide a phenomenological profile of challenging aspects of experiences with psilocybin. Factor scores were associated with difficulty, meaningfulness, spiritual significance, and change in well-being attributed to the challenging experiences. The factor structure did not differ based on gender or prior struggle with anxiety or depression. The Challenging Experience Questionnaire provides a basis for future investigation of predictors and outcomes of challenging experiences with classic hallucinogens. © The Author(s) 2016.

  18. Photons, photosynthesis, and high-performance computing: challenges, progress, and promise of modeling metabolism in green algae

    International Nuclear Information System (INIS)

    Chang, C H; Graf, P; Alber, D M; Kim, K; Murray, G; Posewitz, M; Seibert, M

    2008-01-01

    The complexity associated with biological metabolism considered at a kinetic level presents a challenge to quantitative modeling. In particular, the relatively sparse knowledge of parameters for enzymes with known kinetic responses is problematic. The possible space of these parameters is of high-dimension, and sampling of such a space typifies a combinatorial explosion of possible dynamic states. However, with sufficient quantitative transcriptomics, proteomics, and metabolomics data at hand, these challenges could be met by high-performance software with sampling, fitting, and optimization capabilities. With this in mind, we present the High-Performance Systems Biology Toolkit HiPer SBTK, an evolving software package to simulate, fit, and optimize metabolite concentrations and fluxes within the space of rate and binding parameters associated with detailed enzyme kinetic models. We present our chosen modeling paradigm for the formulation of metabolic pathway models, the means to address the challenge of representing such models in a precise and persistent fashion using the standardized Systems Biology Markup Language, and our second-generation model of H2-associated Chlamydomonas metabolism. Processing of such models for hierarchically parallelized simulation and optimization, job specification by the user through a GUI interface, software capabilities and initial scaling data, and the mapping of the computation to biological questions is also discussed. Moreover, we present near-term future software and model development goals

  19. Designing a system for patients controlling providers' access to their electronic health records: organizational and technical challenges.

    Science.gov (United States)

    Leventhal, Jeremy C; Cummins, Jonathan A; Schwartz, Peter H; Martin, Douglas K; Tierney, William M

    2015-01-01

    Electronic health records (EHRs) are proliferating, and financial incentives encourage their use. Applying Fair Information Practice principles to EHRs necessitates balancing patients' rights to control their personal information with providers' data needs to deliver safe, high-quality care. We describe the technical and organizational challenges faced in capturing patients' preferences for patient-controlled EHR access and applying those preferences to an existing EHR. We established an online system for capturing patients' preferences for who could view their EHRs (listing all participating clinic providers individually and categorically-physicians, nurses, other staff) and what data to redact (none, all, or by specific categories of sensitive data or patient age). We then modified existing data-viewing software serving a state-wide health information exchange and a large urban health system and its primary care clinics to allow patients' preferences to guide data displays to providers. Patients could allow or restrict data displays to all clinicians and staff in a demonstration primary care clinic, categories of providers (physicians, nurses, others), or individual providers. They could also restrict access to all EHR data or any or all of five categories of sensitive data (mental and reproductive health, sexually transmitted diseases, HIV/AIDS, and substance abuse) and for specific patient ages. The EHR viewer displayed data via reports, data flowsheets, and coded and free text data displayed by Google-like searches. Unless patients recorded restrictions, by default all requested data were displayed to all providers. Data patients wanted restricted were not displayed, with no indication they were redacted. Technical barriers prevented redacting restricted information in free textnotes. The program allowed providers to hit a "Break the Glass" button to override patients' restrictions, recording the date, time, and next screen viewed. Establishing patient-control

  20. The physicochemical process of bacterial attachment to abiotic surfaces: Challenges for mechanistic studies, predictability and the development of control strategies.

    Science.gov (United States)

    Wang, Yi; Lee, Sui Mae; Dykes, Gary

    2015-01-01

    Bacterial attachment to abiotic surfaces can be explained as a physicochemical process. Mechanisms of the process have been widely studied but are not yet well understood due to their complexity. Physicochemical processes can be influenced by various interactions and factors in attachment systems, including, but not limited to, hydrophobic interactions, electrostatic interactions and substratum surface roughness. Mechanistic models and control strategies for bacterial attachment to abiotic surfaces have been established based on the current understanding of the attachment process and the interactions involved. Due to a lack of process control and standardization in the methodologies used to study the mechanisms of bacterial attachment, however, various challenges are apparent in the development of models and control strategies. In this review, the physicochemical mechanisms, interactions and factors affecting the process of bacterial attachment to abiotic surfaces are described. Mechanistic models established based on these parameters are discussed in terms of their limitations. Currently employed methods to study these parameters and bacterial attachment are critically compared. The roles of these parameters in the development of control strategies for bacterial attachment are reviewed, and the challenges that arise in developing mechanistic models and control strategies are assessed.

  1. High-Level Waste (HLW) Feed Process Control Strategy

    International Nuclear Information System (INIS)

    STAEHR, T.W.

    2000-01-01

    The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system

  2. Robust enhancement of high harmonic generation via attosecond control of ionization.

    Science.gov (United States)

    Bruner, Barry D; Krüger, Michael; Pedatzur, Oren; Orenstein, Gal; Azoury, Doron; Dudovich, Nirit

    2018-04-02

    High-harmonic generation (HHG) is a powerful tool to generate coherent attosecond light pulses in the extreme ultraviolet. However, the low conversion efficiency of HHG at the single atom level poses a significant practical limitation for many applications. Enhancing the efficiency of the process defines one of the primary challenges in the application of HHG as an advanced XUV source. In this work, we demonstrate a new mechanism, which in contrast to current methods, enhances the HHG conversion efficiency purely on a single particle level. We show that using a bichromatic driving field, sub-optical-cycle control and enhancement of the tunnelling ionization rate can be achieved, leading to enhancements in HHG efficiency by up to two orders of magnitude. Our method advances the perspectives of HHG spectroscopy, where isolating the single particle response is an essential component, and offers a simple route toward scalable, robust XUV sources.

  3. DuraChem trademark - challenges and solutions

    International Nuclear Information System (INIS)

    Howard, I.S.; Bowan, B.W.; Kirshe, M.H.

    1996-01-01

    Vitrification of low-level ion exchange resins represents numerous challenges never before successfully accomplished. These challenges include (1) Feed material preparation and transfer, (2) Melter temperature and volume control, (3) Glass composition, stabilization, and control, and (4) Off-gas treatment and particulate capture. The DuraChem trademark team of Chem-Nuclear Systems, Inc. and GTS Duratek, Inc. began its journey in 1994 and is in the process of starting-up the first centralized vitrification facility for commercial ion-exchange and filtration media. This paper addresses each of the challenges and provides an update of this unique volume-reduction and stabilization technology

  4. High quality flux control system for electron gun evaporation

    International Nuclear Information System (INIS)

    Appelbloom, A.M.; Hadley, P.; van der Marel, D.; Mooij, J.E.

    1991-01-01

    This paper reports on a high quality flux control system for electron gun evaporation developed and tested for the MBE growth of high temperature superconductors. The system can be applied to any electron gun without altering the electron gun itself. Essential elements of the system are a high bandwidth mass spectrometer, control electronics and a high voltage modulator to sweep the electron beam over the melt at high frequencies. the sweep amplitude of the electron beam is used to control the evaporation flux at high frequencies. The feedback loop of the system has a bandwidth of over 100 Hz, which makes it possible to grow superlattices and layered structures in a fast and precisely controlled manner

  5. Current vector control challenges in the fight against malaria.

    Science.gov (United States)

    Benelli, Giovanni; Beier, John C

    2017-10-01

    , presence of behavioral avoidance, high vector biodiversity, competitive and food web interactions, lack of insights on mosquito dispersal and mating behavior, and the impact of environmental changes on mosquito ecological traits. Overall, the trans-disciplinary cooperation among parasitologists and entomologists is crucial to ensure proper evaluation of the epidemiological impact triggered by novel mosquito vector control strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. 17th Workshop on MHD Stability Control: addressing the disruption challenge for ITER

    Science.gov (United States)

    Buttery, Richard

    2013-08-01

    This annual workshop on magnetohydrodynamic stability control was held on 5-7 November 2012 at Columbia University in the city of New York, in the aftermath of a violent hydrodynamic instability event termed 'Hurricane Sandy'. Despite these challenging circumstances, Columbia University managed an excellent meeting, enabling the full participation of the community. This Workshop has been held since 1996 to help in the development of understanding and control of magnetohydrodynamic (MHD) instabilities for future fusion reactors. It covers a wide range of stability topics—from disruptions, to tearing modes, error fields, edge-localized modes (ELMs), resistive wall modes (RWMs) and ideal MHD—spanning many device types (tokamaks, stellarators and reversed field pinches) to identify commonalities in the physics and a means of control. The theme for 2012 was 'addressing the disruption challenge for ITER', and thus the first day had a heavy focus on both the avoidance and mitigation of disruptions in ITER. Key elements included understanding how to apply 3D fields to maintain stability, as well as managing the disruption process itself through mitigating loads in the thermal quench and handling so called 'runaway electrons'. This culminated in a panel discussion on the disruption mitigation strategy for ITER, which noted that heat load asymmetries during the thermal quench appear to be an artifact of MHD processes, and that runaway electron generation may be inevitable, suggesting research should focus on control and dissipation of the runaway beam. The workshop was combined this year with the annual US-Japan MHD Workshop, with a special section looking more deeply at 'Fundamentals of 3D Perturbed Equilibrium Control', with interesting sessions on 3D equilibrium reconstruction, RWM physics, novel control concepts such as non-magnetic sensing, adaptive control, q operation, and the effects of flow. The final day turned to tearing mode interactions, exploring the state

  7. Physiological responses of growing pigs to high ambient temperature and/or inflammatory challenges

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Reis Furtado Campos

    Full Text Available ABSTRACT Global warming is one of the major environmental threats facing the world in the 21st century. This fact will have a significant impact on pig production due to its direct effects on welfare, health, and performance of pigs. Besides, the effects of high temperatures will presumably become more important over the next decades due to the development of pig production in developing countries mainly located in tropical and subtropical areas, where animals are often exposed to ambient temperatures above their thermal comfort zone. Furthermore, pigs reared in tropical areas are often confronted to sanitary challenges including poor hygiene conditions, lack of respect for sanitary rules, and pathogens. This results in the stimulation of the immune system and, as a consequence, in the production of pro-inflammatory cytokines and neuroendocrine adjustments that, in turn, usually have a negative impact on growth and feed efficiency. Although the effects of high ambient temperature and disease on pig physiology and performance have been well documented in literature, little is known about the associated effects of both factors. This understanding may contribute to a better quantification and comprehension of the physiological and metabolic disturbances occurring in practical conditions of pig production in tropical areas and, more generally, in many other geographic areas that will be influenced by the perspective of global warming. Therefore, the objective of this work is to provide an overview of recent research advances on the physiological responses of growing pigs during acclimation to high ambient temperature and on the potential effects of high ambient temperature on the ability of growing pigs to resist, cope with, or recover from an inflammatory challenge.

  8. Meeting the challenges in managing TMI-2 liquid waste and resolving disposal issues

    International Nuclear Information System (INIS)

    Schmitt, R.C.; Brown, G.R.; Ayers, A.L. Jr.

    1986-01-01

    This paper describes challenges of decontaminating water resulting from the accident at the Unit 2 of the Three Mile Island nuclear power station, disposing of highly contaminated prefilter liners as commercial low-level wastes, and controlling gas generation in highly loaded, disposable zeolite vessels. Disposal of EPICOR-II prefilter liners necessitated development of the first-of-a-kind, concrete high-integrity containers. Shipment of zeolite vessels for use in a research and development program required developing and testing a catalytic recombiner that controlled gases produced by radiolytic decomposition of interstitial water in the vessels

  9. A Reduced-Order Controller Considering High-Order Modal Information of High-Rise Buildings for AMD Control System with Time-Delay

    Directory of Open Access Journals (Sweden)

    Zuo-Hua Li

    2017-01-01

    Full Text Available Time-delays of control force calculation, data acquisition, and actuator response will degrade the performance of Active Mass Damper (AMD control systems. To reduce the influence, model reduction method is used to deal with the original controlled structure. However, during the procedure, the related hierarchy information of small eigenvalues will be directly discorded. As a result, the reduced-order model ignores the information of high-order mode, which will reduce the design accuracy of an AMD control system. In this paper, a new reduced-order controller based on the improved Balanced Truncation (BT method is designed to reduce the calculation time and to retain the abandoned high-order modal information. It includes high-order natural frequency, damping ratio, and vibration modal information of the original structure. Then, a control gain design method based on Guaranteed Cost Control (GCC algorithm is presented to eliminate the adverse effects of data acquisition and actuator response time-delays in the design process of the reduced-order controller. To verify its effectiveness, the proposed methodology is applied to a numerical example of a ten-storey frame and an experiment of a single-span four-storey steel frame. Both numerical and experimental results demonstrate that the reduced-order controller with GCC algorithm has an excellent control effect; meanwhile it can compensate time-delays effectively.

  10. Building a Grad Nation: Progress and Challenge in Ending the High School Dropout Epidemic. Annual Update 2015

    Science.gov (United States)

    DePaoli, Jennifer L.; Fox, Joanna Hornig; Ingram, Erin S.; Maushard, Mary; Bridgeland, John M.; Balfanz, Robert

    2015-01-01

    In 2013, the national high school graduation rate hit a record high of 81.4 percent, and for the third year in a row, the nation remained on pace to meet the 90 percent goal by the Class of 2020. This sixth annual update on America's high school dropout challenge shows that these gains have been made possible by raising graduation rates for…

  11. Sub-15 nm nano-pattern generation by spacer width control for high density precisely positioned self-assembled device nanomanufacturing

    KAUST Repository

    Rojas, Jhonathan Prieto; Hussain, Muhammad Mustafa

    2012-01-01

    We present a conventional micro-fabrication based thin film vertical sidewall (spacer) width controlled nano-gap fabrication process to create arrays of nanopatterns for high density precisely positioned self-assembled nanoelectronics device integration. We have used conventional optical lithography to create base structures and then silicon nitride (Si 3N4) based spacer formation via reactive ion etching. Control of Si3N4 thickness provides accurate control of vertical sidewall (spacer) besides the base structures. Nano-gaps are fabricated between two adjacent spacers whereas the width of the gap depends on the gap between two adjacent base structures minus width of adjacent spacers. We demonstrate the process using a 32 nm node complementary metal oxide semiconductor (CMOS) platform to show its compatibility for very large scale heterogeneous integration of top-down and bottom-up fabrication as well as conventional and selfassembled nanodevices. This process opens up clear opportunity to overcome the decade long challenge of high density integration of self-assembled devices with precise position control. © 2012 IEEE.

  12. Sub-15 nm nano-pattern generation by spacer width control for high density precisely positioned self-assembled device nanomanufacturing

    KAUST Repository

    Rojas, Jhonathan Prieto

    2012-08-01

    We present a conventional micro-fabrication based thin film vertical sidewall (spacer) width controlled nano-gap fabrication process to create arrays of nanopatterns for high density precisely positioned self-assembled nanoelectronics device integration. We have used conventional optical lithography to create base structures and then silicon nitride (Si 3N4) based spacer formation via reactive ion etching. Control of Si3N4 thickness provides accurate control of vertical sidewall (spacer) besides the base structures. Nano-gaps are fabricated between two adjacent spacers whereas the width of the gap depends on the gap between two adjacent base structures minus width of adjacent spacers. We demonstrate the process using a 32 nm node complementary metal oxide semiconductor (CMOS) platform to show its compatibility for very large scale heterogeneous integration of top-down and bottom-up fabrication as well as conventional and selfassembled nanodevices. This process opens up clear opportunity to overcome the decade long challenge of high density integration of self-assembled devices with precise position control. © 2012 IEEE.

  13. Design and preliminary evaluation of the FINGER rehabilitation robot: controlling challenge and quantifying finger individuation during musical computer game play.

    Science.gov (United States)

    Taheri, Hossein; Rowe, Justin B; Gardner, David; Chan, Vicki; Gray, Kyle; Bower, Curtis; Reinkensmeyer, David J; Wolbrecht, Eric T

    2014-02-04

    This paper describes the design and preliminary testing of FINGER (Finger Individuating Grasp Exercise Robot), a device for assisting in finger rehabilitation after neurologic injury. We developed FINGER to assist stroke patients in moving their fingers individually in a naturalistic curling motion while playing a game similar to Guitar Hero. The goal was to make FINGER capable of assisting with motions where precise timing is important. FINGER consists of a pair of stacked single degree-of-freedom 8-bar mechanisms, one for the index and one for the middle finger. Each 8-bar mechanism was designed to control the angle and position of the proximal phalanx and the position of the middle phalanx. Target positions for the mechanism optimization were determined from trajectory data collected from 7 healthy subjects using color-based motion capture. The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths. For initial evaluation, we asked individuals with a stroke (n = 16) and without impairment (n = 4) to play a game similar to Guitar Hero while connected to FINGER. Precision design, low friction bearings, and separate high speed linear actuators allowed FINGER to individually actuate the fingers with a high bandwidth of control (-3 dB at approximately 8 Hz). During the tests, we were able to modulate the subject's success rate at the game by automatically adjusting the controller gains of FINGER. We also used FINGER to measure subjects' effort and finger individuation while playing the game. Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke.

  14. Machine Learning Control For Highly Reconfigurable High-Order Systems

    Science.gov (United States)

    2015-01-02

    calibration and applications,” Mechatronics and Embedded Systems and Applications (MESA), 2010 IEEE/ASME International Conference on, IEEE, 2010, pp. 38–43...AFRL-OSR-VA-TR-2015-0012 MACHINE LEARNING CONTROL FOR HIGHLY RECONFIGURABLE HIGH-ORDER SYSTEMS John Valasek TEXAS ENGINEERING EXPERIMENT STATION...DIMENSIONAL RECONFIGURABLE SYSTEMS FA9550-11-1-0302 Period of Performance 1 July 2011 – 29 September 2014 John Valasek Aerospace Engineering

  15. Challenges in graphene integration for high-frequency electronics

    Science.gov (United States)

    Giannazzo, F.; Fisichella, G.; Greco, G.; Roccaforte, F.

    2016-06-01

    This paper provides an overview of the state-of-the-art research on graphene (Gr) for high-frequency (RF) devices. After discussing current limitations of lateral Gr RF transistors, novel vertical devices concepts such as the Gr Base Hot Electron Transistor (GBHET) will be introduced and the main challenges in Gr integration within these architectures will be discussed. In particular, a GBHET device based on Gr/AlGaN/GaN heterostructure will be considered. An approach to the fabrication of this heterostructure by transfer of CVD grown Gr on copper to the AlGaN surface will be presented. The morphological and electrical properties of this system have been investigated at nanoscale by atomic force microscopy (AFM) and conductive atomic force microscopy (CAFM). In particular, local current-voltage measurements by the CAFM probe revealed the formation of a Schottky contact with low barrier height (˜0.41 eV) and excellent lateral uniformity between Gr and AlGaN. Basing on the electrical parameters extracted from this characterization, the theoretical performances of a GBHET formed by a metal/Al2O3/Gr/AlGaN/GaN stack have been evaluated.

  16. Alien vs. predator: bacterial challenge alters coral microbiomes unless controlled by Halobacteriovorax predators

    Directory of Open Access Journals (Sweden)

    Rory M. Welsh

    2017-05-01

    Full Text Available Coral microbiomes are known to play important roles in organismal health, response to environmental stress, and resistance to disease. The coral microbiome contains diverse assemblages of resident bacteria, ranging from defensive and metabolic symbionts to opportunistic bacteria that may turn harmful in compromised hosts. However, little is known about how these bacterial interactions influence the mechanism and controls of overall structure, stability, and function of the microbiome. We sought to test how coral microbiome dynamics were affected by interactions between two bacteria: Vibrio coralliilyticus, a known temperature-dependent pathogen of some corals, and Halobacteriovorax, a unique bacterial predator of Vibrio and other gram-negative bacteria. We challenged reef-building coral with V. coralliilyticus in the presence or absence of Halobacteriovorax predators, and monitored microbial community dynamics with 16S rRNA gene profiling time-series. Vibrio coralliilyticus inoculation increased the mean relative abundance of Vibrios by greater than 35% from the 4 to 8 hour time point, but not in the 24 & 32 hour time points. However, strong secondary effects of the Vibrio challenge were also observed for the rest of the microbiome such as increased richness (observed species, and reduced stability (increased beta-diversity. Moreover, after the transient increase in Vibrios, two lineages of bacteria (Rhodobacterales and Cytophagales increased in coral tissues, suggesting that V. coralliilyticus challenge opens niche space for these known opportunists. Rhodobacterales increased from 6.99% (±0.05 SEM to a maximum mean relative abundance of 48.75% (±0.14 SEM in the final time point and Cytophagales from <0.001% to 3.656%. Halobacteriovorax predators are commonly present at low-abundance on coral surfaces. Based on the keystone role of predators in many ecosystems, we hypothesized that Halobacteriovorax predators might help protect corals by

  17. Long-term dietary intervention trials: critical issues and challenges

    Directory of Open Access Journals (Sweden)

    Crichton Georgina E

    2012-07-01

    Full Text Available Abstract Background There are many challenges involved in running randomised controlled dietary intervention trials that investigate health outcomes. The aim of this paper was to evaluate the recruitment process, retention of participants and challenges faced in our dairy intervention trial, and to provide strategies to combat the difficulties of running long-term dietary intervention trials. Methods A 12-month, randomised, two-way crossover study was conducted in overweight adults with habitually low dairy food consumption to assess the effects of a high dairy intake (4 servings of reduced-fat dairy per day compared with a low dairy intake (1 serving of reduced-fat dairy per day on measures of cardiometabolic and cognitive health. On completion of the high dairy intake phase, each participant was interviewed about their experience in the trial and responses were used to evaluate the key issues for study participants. Results Although the recruitment target was achieved, high rates of attrition (49.3% and difficulties maintaining participant compliance (reported by 37.8% of participants were major threats to the viability of the study. Factors that contributed to the high attrition included inability to comply with the dietary requirements of the study protocol (27.0%, health problems or medication changes (24.3% and time commitment (10.8%. Conclusion Attrition and adherence to study requirements present challenges to trials requiring longer-term dietary change. Including a run-in period to further assess the motivation, commitment and availability of participants, maintaining regular contact with participants during control phases, minimising time commitment, providing flexibility with dietary requirements, facilitating positive experiences, and stringent monitoring of diet are some key recommendations for future dietary intervention trials. Trial registration Australia and New Zealand Clinical Trials Registry (ACTRN 12608000538347

  18. Challenges and solutions for high-volume testing of silicon photonics

    Science.gov (United States)

    Polster, Robert; Dai, Liang Yuan; Oikonomou, Michail; Cheng, Qixiang; Rumley, Sebastien; Bergman, Keren

    2018-02-01

    The first generation of silicon photonic products is now commercially available. While silicon photonics possesses key economic advantages over classical photonic platforms, it has yet to become a commercial success because these advantages can be fully realized only when high-volume testing of silicon photonic devices is made possible. We discuss the costs, challenges, and solutions of photonic chip testing as reported in the recent research literature. We define and propose three underlying paradigms that should be considered when creating photonic test structures: Design for Fast Coupling, Design for Minimal Taps, and Design for Parallel Testing. We underline that a coherent test methodology must be established prior to the design of test structures, and demonstrate how an optimized methodology dramatically reduces the burden when designing for test, by reducing the needed complexity of test structures.

  19. Is there a temperature? conceptual challenges at high energy, acceleration and complexity

    CERN Document Server

    Sándor Biró, Tamás

    2011-01-01

    Physical bodies can be hot or cold, moving or standing,simple or complex. In all such cases one assumes that their respective temperature is a well defined attribute.  What if, however, the ordinary measurement of temperature by direct body contact is not possible?  One conjectures its value, and yes, its very existence, by reasoning based on basic principles of thermodynamics. Is There a Temperature?  Conceptual Challenges at High Energy, Acceleration and Complexity, by Dr. Tamás Sándor Bíró, begins by asking the questions “Do we understand and can we explain in a unified framework the temperature of distant radiation sources, including event horizons, and that of the quark matter produced in high energy accelerator experiments? Or the astounding fluctuations on financial markets?” The book reviews the concept of temperature from its beginnings through the evolution of classical thermodynamics and atomic statistical physics through contemporary models of high energy particle matter.  Based on the...

  20. High levels of physical activity are associated with poorer asthma control in young females but not in males.

    Science.gov (United States)

    Lövström, Ludvig; Emtner, Margareta; Alving, Kjell; Nordvall, Lennart; Borres, Magnus P; Janson, Christer; Malinovschi, Andrei

    2016-01-01

    Earlier studies on the levels of physical activity in asthma patients compared with controls have yielded varying results. We have previously reported that high versus moderate levels of physical activity were associated with higher prevalence of wheezing, especially in females. Here we studied the levels of physical activity in young patients with asthma and healthy subjects and their effect on asthma control. Four hundred eight physician-diagnosed patients with asthma and 118 controls (10-34 years) answered questions concerning frequency and/or duration of physical activity and undertook the Asthma Control Test (ACT), spirometry, methacholine challenges and exhaled nitric oxide measurements. Asthma patients were more frequently physically active (P = 0.01) and for longer durations (P = 0.002) than controls. Highly versus moderately physically active patients with asthma had a higher prevalence of not well-controlled asthma (ACT < 20) when physical activity was assessed by frequency (40.6% vs 24.1%, P = 0.001) or duration (39.0% vs 21.7%, P < 0.001). This was only seen in females who had reduced ACT items (P < 0.05). Frequently versus moderately active females had an odds ratio of 4.81 (2.43, 9.51) to have ACT < 20, while no such effect was found in males (OR 1.18 (0.61, 2.30)) and this interaction was statistically significantly associated with gender (P = 0.003). No differences in fraction of exhaled nitric oxide or methacholine reactivity were found between moderately and highly physically active females with asthma. Young asthma patients were more active than controls. High levels of physical activity were associated with poor asthma control as judged by the ACT in females, but not in males, and this appears unrelated to airway inflammation or responsiveness. © 2015 Asian Pacific Society of Respirology.

  1. Computer controlled high voltage system

    Energy Technology Data Exchange (ETDEWEB)

    Kunov, B; Georgiev, G; Dimitrov, L [and others

    1996-12-31

    A multichannel computer controlled high-voltage power supply system is developed. The basic technical parameters of the system are: output voltage -100-3000 V, output current - 0-3 mA, maximum number of channels in one crate - 78. 3 refs.

  2. Active Control of High-Speed Free Jets Using High-Frequency Excitation

    Science.gov (United States)

    Upadhyay, Puja

    Control of aerodynamic noise generated by high-performance jet engines continues to remain a serious problem for the aviation community. Intense low frequency noise produced by large-scale coherent structures is known to dominate acoustic radiation in the aft angles. A tremendous amount of research effort has been dedicated towards the investigation of many passive and active flow control strategies to attenuate jet noise, while keeping performance penalties to a minimum. Unsteady excitation, an active control technique, seeks to modify acoustic sources in the jet by leveraging the naturally-occurring flow instabilities in the shear layer. While excitation at a lower range of frequencies that scale with the dynamics of large-scale structures, has been attempted by a number of studies, effects at higher excitation frequencies remain severely unexplored. One of the major limitations stems from the lack of appropriate flow control devices that have sufficient dynamic response and/or control authority to be useful in turbulent flows, especially at higher speeds. To this end, the current study seeks to fulfill two main objectives. First, the design and characterization of two high-frequency fluidic actuators (25 and 60 kHz) are undertaken, where the target frequencies are guided by the dynamics of high-speed free jets. Second, the influence of high-frequency forcing on the aeroacoustics of high-speed jets is explored in some detail by implementing the nominally 25 kHz actuator on a Mach 0.9 (Re D = 5 x 105) free jet flow field. Subsequently, these findings are directly compared to the results of steady microjet injection experiments performed in the same rig and to prior jet noise control studies, where available. Finally, limited acoustic measurements were also performed by implementing the nominally 25 kHz actuators on jets at higher Mach numbers, including shock containing jets, and elevated temperatures. Using lumped element modeling as an initial guide, the current

  3. Challenges of characterization of radioactive waste with High composition variability and their consequences measurement methodology

    International Nuclear Information System (INIS)

    Lexa, D.

    2014-01-01

    Radioactive waste characterization is a key step in every nuclear decommissioning project. It normally relies on a combination of facility operational history with results of destructive and non-destructive analysis. A particularly challenging situation arises when historical waste from a nuclear research facility is to be characterized, meaning little or no radiological information is available and the composition of the waste is highly variable. The nuclide vector concept is of limited utility, resulting in increased requirements placed on both the extent and performance of destructive and non-destructive analysis. Specific challenges are illustrated on an example of the decommissioning project underway at the Joint Research Center of the European Commission in Ispra. (author)

  4. Seven challenges for modelling indirect transmission: Vector-borne diseases, macroparasites and neglected tropical diseases

    Directory of Open Access Journals (Sweden)

    T. Déirdre Hollingsworth

    2015-03-01

    Full Text Available Many of the challenges which face modellers of directly transmitted pathogens also arise when modelling the epidemiology of pathogens with indirect transmission – whether through environmental stages, vectors, intermediate hosts or multiple hosts. In particular, understanding the roles of different hosts, how to measure contact and infection patterns, heterogeneities in contact rates, and the dynamics close to elimination are all relevant challenges, regardless of the mode of transmission. However, there remain a number of challenges that are specific and unique to modelling vector-borne diseases and macroparasites. Moreover, many of the neglected tropical diseases which are currently targeted for control and elimination are vector-borne, macroparasitic, or both, and so this article includes challenges which will assist in accelerating the control of these high-burden diseases. Here, we discuss the challenges of indirect measures of infection in humans, whether through vectors or transmission life stages and in estimating the contribution of different host groups to transmission. We also discuss the issues of “evolution-proof” interventions against vector-borne disease.

  5. Seven challenges for modelling indirect transmission: vector-borne diseases, macroparasites and neglected tropical diseases.

    Science.gov (United States)

    Hollingsworth, T Déirdre; Pulliam, Juliet R C; Funk, Sebastian; Truscott, James E; Isham, Valerie; Lloyd, Alun L

    2015-03-01

    Many of the challenges which face modellers of directly transmitted pathogens also arise when modelling the epidemiology of pathogens with indirect transmission--whether through environmental stages, vectors, intermediate hosts or multiple hosts. In particular, understanding the roles of different hosts, how to measure contact and infection patterns, heterogeneities in contact rates, and the dynamics close to elimination are all relevant challenges, regardless of the mode of transmission. However, there remain a number of challenges that are specific and unique to modelling vector-borne diseases and macroparasites. Moreover, many of the neglected tropical diseases which are currently targeted for control and elimination are vector-borne, macroparasitic, or both, and so this article includes challenges which will assist in accelerating the control of these high-burden diseases. Here, we discuss the challenges of indirect measures of infection in humans, whether through vectors or transmission life stages and in estimating the contribution of different host groups to transmission. We also discuss the issues of "evolution-proof" interventions against vector-borne disease. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Controllable Edge Oxidation and Bubbling Exfoliation Enable the Fabrication of High Quality Water Dispersible Graphene.

    Science.gov (United States)

    Tian, Suyun; Sun, Jing; Yang, Siwei; He, Peng; Wang, Gang; Di, Zengfeng; Ding, Guqiao; Xie, Xiaoming; Jiang, Mianheng

    2016-09-26

    Despite significant progresses made on mass production of chemically exfoliated graphene, the quality, cost and environmental friendliness remain major challenges for its market penetration. Here, we present a fast and green exfoliation strategy for large scale production of high quality water dispersible few layer graphene through a controllable edge oxidation and localized gas bubbling process. Mild edge oxidation guarantees that the pristine sp 2 lattice is largely intact and the edges are functionalized with hydrophilic groups, giving rise to high conductivity and good water dispersibility at the same time. The aqueous concentration can be as high as 5.0 mg mL -1 , which is an order of magnitude higher than previously reports. The water soluble graphene can be directly spray-coated on various substrates, and the back-gated field effect transistor give hole and electron mobility of ~496 and ~676 cm 2 V -1 s -1 , respectively. These results achieved are expected to expedite various applications of graphene.

  7. Controllable Edge Oxidation and Bubbling Exfoliation Enable the Fabrication of High Quality Water Dispersible Graphene

    Science.gov (United States)

    Tian, Suyun; Sun, Jing; Yang, Siwei; He, Peng; Wang, Gang; di, Zengfeng; Ding, Guqiao; Xie, Xiaoming; Jiang, Mianheng

    2016-09-01

    Despite significant progresses made on mass production of chemically exfoliated graphene, the quality, cost and environmental friendliness remain major challenges for its market penetration. Here, we present a fast and green exfoliation strategy for large scale production of high quality water dispersible few layer graphene through a controllable edge oxidation and localized gas bubbling process. Mild edge oxidation guarantees that the pristine sp2 lattice is largely intact and the edges are functionalized with hydrophilic groups, giving rise to high conductivity and good water dispersibility at the same time. The aqueous concentration can be as high as 5.0 mg mL-1, which is an order of magnitude higher than previously reports. The water soluble graphene can be directly spray-coated on various substrates, and the back-gated field effect transistor give hole and electron mobility of ~496 and ~676 cm2 V-1 s-1, respectively. These results achieved are expected to expedite various applications of graphene.

  8. Challenges to achievement of metal sustainability in our high-tech society.

    Science.gov (United States)

    Izatt, Reed M; Izatt, Steven R; Bruening, Ronald L; Izatt, Neil E; Moyer, Bruce A

    2014-04-21

    Achievement of sustainability in metal life cycles from mining of virgin ore to consumer and industrial devices to end-of-life products requires greatly increased recycling rates and improved processing of metals using conventional and green chemistry technologies. Electronic and other high-tech products containing precious, toxic, and specialty metals usually have short lifetimes and low recycling rates. Products containing these metals generally are incinerated, discarded as waste in landfills, or dismantled in informal recycling using crude and environmentally irresponsible procedures. Low recycling rates of metals coupled with increasing demand for high-tech products containing them necessitate increased mining with attendant environmental, health, energy, water, and carbon-footprint consequences. In this tutorial review, challenges to achieving metal sustainability, including projected use of urban mining, in present high-tech society are presented; health, environmental, and economic incentives for various government, industry, and public stakeholders to improve metal sustainability are discussed; a case for technical improvements, including use of molecular recognition, in selective metal separation technology, especially for metal recovery from dilute feed stocks is given; and global consequences of continuing on the present path are examined.

  9. Current challenges in tobacco control.

    Science.gov (United States)

    Slama, K

    2004-10-01

    Tobacco is the world's biggest preventable killer, but the circumstances of its history, the power and influence of its commerce and the nature of addiction make it a very difficult public health issue. Determinants of smoking are both individual and environmental. Genetics and environment influence to varying degrees all of the steps in a smoker's career. Persistence of use, degree of addiction to nicotine and difficulty in stopping are influenced by inherited traits and nicotine susceptibility, whereas the social environment and the individual's cognitions are the key factors in starting smoking and successfully stopping smoking. The tools available to tobacco control include influencing the social and cultural norms concerning tobacco; legislative and regulatory measures to protect the population and to limit tobacco industry marketing tactics, now encapsulated in the Framework Convention on Tobacco Control; and programmes to enhance the chance of not starting and successfully stopping. Strategies for tobacco control must work at both societal and individual levels, and directions are being taken that include genetic, pharmacological, behavioural, socio-cultural and international approaches.

  10. Six challenges in the eradication of infectious diseases

    Directory of Open Access Journals (Sweden)

    Petra Klepac

    2015-03-01

    Full Text Available Eradication and elimination are increasingly a part of the global health agenda. Once control measures have driven infection to low levels, the ecology of disease may change posing challenges for eradication efforts. These challenges vary from identifying pockets of susceptibles, improving monitoring during and after the endgame, to quantifying the economics of disease eradication versus sustained control, all of which are shaped and influenced by processes of loss of immunity, susceptible build-up, emergence of resistance, population heterogeneities and non-compliance with control measures. Here we discuss how modelling can be used to address these challenges.

  11. Baseline integrated behavioural and biological assessment among most at-risk populations in six high-prevalence states of India: design and implementation challenges.

    Science.gov (United States)

    Saidel, Tobi; Adhikary, Rajatashuvra; Mainkar, Mandar; Dale, Jayesh; Loo, Virginia; Rahman, Motiur; Ramesh, Banadakoppa M; Paranjape, Ramesh S

    2008-12-01

    This paper presents key methodological approaches and challenges in implementing and analysing the first round of the integrated biobehavioural assessment of most-at-risk populations, conducted in conjunction with evaluation of Avahan, the India AIDS initiative. The survey collected data on HIV risk behaviours, sexually transmitted infections and HIV prevalence in 29 districts in six high-prevalence states of India. Groups included female sex workers and clients, men who have sex with men, injecting drug users and truck drivers. Strategies for overcoming some challenges of the large-scale surveys among vulnerable populations, including sampling hidden populations, involvement of the communities targeted by the survey, laboratory and quality control in remote, non-clinic field settings, and data analysis and data use are presented. Satisfying the need for protocols, guidelines and tools that allowed for sufficient standardization, while being tailored enough to fit diverse local situations on such a large scale, with so many implementing partners, emerged as a major management challenge. A major lesson from the first round is the vital importance of investing upfront time in tailoring the sampling methods, data collection instruments, and analysis plan to match measurement objectives. Despite the challenges, the integrated biobehavioural assessment was a huge achievement, and was largely successful in providing previously unavailable information about the HIV situation among populations that are critical to the curtailment of HIV spread in India. Lessons from the first round will be used to evolve the second round into an exercise with increased evaluative capability for Avahan.

  12. Connecting to the Professor: Impact of the Student-Faculty Relationship in a Highly Challenging Course

    Science.gov (United States)

    Micari, Marina; Pazos, Pilar

    2012-01-01

    While many factors play into college student success, interaction with faculty has been identified as a key component. In highly challenging and anxiety-provoking courses, the student-faculty relationship may be all the more important. This study uses organic chemistry as a case example to investigate the role of the student-faculty relationship…

  13. High Precision Current Control for the LHC Main Power Converters

    CERN Document Server

    Thiesen, H; Hudson, G; King, Q; Montabonnet, V; Nisbet, D; Page, S

    2010-01-01

    Since restarting at the end of 2009, the LHC has reached a new energy record in March 2010 with the two 3.5 TeV beams. To achieve the performance required for the good functioning of the accelerator, the currents in the main circuits (Main Bends and Main Quadrupoles) must be controlled with a higher precision than ever previously requested for a particle accelerator at CERN: a few parts per million (ppm) of nominal current. This paper describes the different challenges that were overcome to achieve the required precision for the current control of the main circuits. Precision tests performed during the hardware commissioning of the LHC illustrate this paper.

  14. The Role of Challenge in Students' Engagement and Competence in High School Science Classrooms: Hispanic and Non-Hispanic Whites Compared

    Science.gov (United States)

    Schmidt, Jennifer A.; Kackar-Cam, Hayal Z.; Strati, Anna D.; Shumow, Lee

    2015-01-01

    This study explores the associations of ethnicity and perceived challenge with high-school students' academic engagement and perceived competence in science. Data were collected through a variant of the Experience Sampling Method in which participants reported on their levels of engagement, perceived competence, and challenge while in science…

  15. Effect of hookworm infection on wheat challenge in celiac disease--a randomised double-blinded placebo controlled trial.

    Directory of Open Access Journals (Sweden)

    A James Daveson

    Full Text Available BACKGROUND AND AIMS: The association between hygiene and prevalence of autoimmune disease has been attributed in part to enteric helminth infection. A pilot study of experimental infection with the hookworm Necator americanus was undertaken among a group of otherwise healthy people with celiac disease to test the potential of the helminth to suppress the immunopathology induced by gluten. METHODS: In a 21-week, double-blinded, placebo-controlled study, we explored the effects of N. americanus infection in 20 healthy, helminth-naïve adults with celiac disease well controlled by diet. Staged cutaneous inoculations with 10 and 5 infective 3(rd stage hookworm larvae or placebo were performed at week-0 and -12 respectively. At week-20, a five day oral wheat challenge equivalent to 16 grams of gluten per day was undertaken. Primary outcomes included duodenal Marsh score and quantification of the immunodominant α-gliadin peptide (QE65-specific systemic interferon-γ-producing cells by ELISpot pre- and post-wheat challenge. RESULTS: Enteric colonisation with hookworm established in all 10 cases, resulting in transiently painful enteritis in 5. Chronic infection was asymptomatic, with no effect on hemoglobin levels. Although some duodenal eosinophilia was apparent, hookworm-infected mucosa retained a healthy appearance. In both groups, wheat challenge caused deterioration in both primary and several secondary outcomes. CONCLUSIONS: Experimental N. americanus infection proved to be safe and enabled testing its effect on a range of measures of the human autoimmune response. Infection imposed no obvious benefit on pathology. TRIAL REGISTRATION: ClinicalTrials.gov NCT00671138.

  16. Challenges and Opportunities in Gen3 Embedded Cooling with High-Quality Microgap Flow

    Science.gov (United States)

    Bar-Cohen, Avram; Robinson, Franklin L.; Deisenroth, David C.

    2018-01-01

    Gen3, Embedded Cooling, promises to revolutionize thermal management of advanced microelectronic systems by eliminating the sequential conductive and interfacial thermal resistances which dominate the present 'remote cooling' paradigm. Single-phase interchip microfluidic flow with high thermal conductivity chips and substrates has been used successfully to cool single transistors dissipating more than 40kW/sq cm, but efficient heat removal from transistor arrays, larger chips, and chip stacks operating at these prodigious heat fluxes would require the use of high vapor fraction (quality), two-phase cooling in intra- and inter-chip microgap channels. The motivation, as well as the challenges and opportunities associated with evaporative embedded cooling in realistic form factors, is the focus of this paper. The paper will begin with a brief review of the history of thermal packaging, reflecting the 70-year 'inward migration' of cooling technology from the computer-room, to the rack, and then to the single chip and multichip module with 'remote' or attached air- and liquid-cooled coldplates. Discussion of the limitations of this approach and recent results from single-phase embedded cooling will follow. This will set the stage for discussion of the development challenges associated with application of this Gen3 thermal management paradigm to commercial semiconductor hardware, including dealing with the effects of channel length, orientation, and manifold-driven centrifugal acceleration on the governing behavior.

  17. Analysis of torque transmitting behavior and wheel slip prevention control during regenerative braking for high speed EMU trains

    Science.gov (United States)

    Xu, Kun; Xu, Guo-Qing; Zheng, Chun-Hua

    2016-04-01

    The wheel-rail adhesion control for regenerative braking systems of high speed electric multiple unit trains is crucial to maintaining the stability, improving the adhesion utilization, and achieving deep energy recovery. There remain technical challenges mainly because of the nonlinear, uncertain, and varying features of wheel-rail contact conditions. This research analyzes the torque transmitting behavior during regenerative braking, and proposes a novel methodology to detect the wheel-rail adhesion stability. Then, applications to the wheel slip prevention during braking are investigated, and the optimal slip ratio control scheme is proposed, which is based on a novel optimal reference generation of the slip ratio and a robust sliding mode control. The proposed methodology achieves the optimal braking performance without the wheel-rail contact information. Numerical simulation results for uncertain slippery rails verify the effectiveness of the proposed methodology.

  18. Newcastle disease virus-based H5 influenza vaccine protects chickens from lethal challenge with a highly pathogenic H5N2 avian influenza virus.

    Science.gov (United States)

    Ma, Jingjiao; Lee, Jinhwa; Liu, Haixia; Mena, Ignacio; Davis, A Sally; Sunwoo, Sun Young; Lang, Yuekun; Duff, Michael; Morozov, Igor; Li, Yuhao; Yang, Jianmei; García-Sastre, Adolfo; Richt, Juergen A; Ma, Wenjun

    2017-01-01

    Since December 2014, Eurasian-origin, highly pathogenic avian influenza H5 viruses including H5N1, H5N2, and H5N8 subtypes (called H5N x viruses), which belong to the H5 clade 2.3.4.4, have been detected in U.S. wild birds. Subsequently, highly pathogenic H5N2 and H5N8 viruses have caused outbreaks in U.S. domestic poultry. Vaccination is one of the most effective ways to control influenza outbreaks and protect animal and public health. Newcastle disease virus (NDV)-based influenza vaccines have been demonstrated to be efficacious and safe in poultry. Herein, we developed an NDV-based H5 vaccine (NDV-H5) that expresses a codon-optimized ectodomain of the hemagglutinin from the A/chicken/Iowa/04-20/2015 (H5N2) virus and evaluated its efficacy in chickens. Results showed that both live and inactivated NDV-H5 vaccines induced hemagglutinin inhibition antibody titers against the H5N2 virus in immunized chickens after prime and booster, and both NDV-H5 vaccines completely protected chickens from lethal challenge with the highly pathogenic H5N2 A/turkey/Minnesota/9845-4/2015 virus. No clinical signs and only minimal virus shedding was observed in both vaccinated groups. In contrast, all mock-vaccinated, H5N2-infected chickens shed virus and died within 5 days post challenge. Furthermore, one dose of the live NDV-H5 vaccine also provided protection of 90% chickens immunized by coarse spraying; after exposure to H5N2 challenge, sera from vaccinated surviving chickens neutralized both highly pathogenic H5N1 and H5N8 viruses. Taken together, our results suggest that the NDV-based H5 vaccine is able to protect chickens against intercontinental highly pathogenic H5N x viruses and can be used by mass application to protect the poultry industry.

  19. Urinary metabolites of histamine and leukotrienes before and after placebo-controlled challenge with ASA and food additives in chronic urticaria patients.

    Science.gov (United States)

    Di Lorenzo, G; Pacor, M L; Vignola, A M; Profita, M; Esposito-Pellitteri, M; Biasi, D; Corrocher, R; Caruso, C

    2002-12-01

    The recovery of mediator metabolites from urine has the potential to provide a rapid, safe, and easily available index of release of mediators. We aimed to determine urinary metabolites of both histamine and leukotrienes (LTs) in patients affected by chronic urticaria (CU). Twenty patients with CU were studied. They were selected on the basis of double-blind placebo-controlled challenge (DBPC) with acetyl salicylic acid (ASA) and food additives. Ten patients (group B) were negative to both challenges. Ten patients (group C) presented urticaria and/or the appearance of angioedema during or 24 h after challenge, with reactions to ASA (five patients) or food additives (five patients). We recruited 15 healthy volunteers as controls (group A). During a second challenge, groups B and C were challenged double-blind with a single dose of ASA, or a specific food additive, or placebo. The healthy group was challenged only with a placebo (talc capsule). Patients in groups B and C were challenged twice: with placebo (as groups B1 and C1) and with ASA (groups B2 and C2) or food additives (C2). Four samples of urine were collected; one during the night before the specific or sham challenge (baseline), and three at 2, 6 and 24 h after the challenge. Urinary methylhistamine (N-MH) and LTE4 were analyzed and normalized for urinary creatinine. For urinary N-MH at baseline, there was a significant difference only between group A and groups B1, B2, C1 and C2 (A vs. B1, P < 0.0001; A vs. B2, P < 0.0001; A vs. C1, P < 0.0001; A vs. C2, P < 0.0001). We detected a significant variation in urinary methylhistamine excretion only in group C2 after 2 h, 6 h and 24 h (P < 0.0001). However, no variations were observed in N-MH excretion rate in the other groups (A, B1, C1) after challenge with placebo, and in B2 after challenge with ASA 20 mg. For urinary LTE4 at baseline no differences were found between the mean values for the different groups. After specific challenge, only C2 patients showed

  20. Mesoporous silica nanoparticles for stimuli-responsive controlled drug delivery: advances, challenges, and outlook

    Directory of Open Access Journals (Sweden)

    Song Y

    2016-12-01

    Full Text Available Yuanhui Song, Yihong Li, Qien Xu, Zhe Liu Wenzhou Institute of Biomaterials and Engineering (WIBE, Wenzhou Medical University, Wenzhou, Zhejiang, People’s Republic of China Abstract: With the development of nanotechnology, the application of nanomaterials in the field of drug delivery has attracted much attention in the past decades. Mesoporous silica nanoparticles as promising drug nanocarriers have become a new area of interest in recent years due to their unique properties and capabilities to efficiently entrap cargo molecules. This review describes the latest advances on the application of mesoporous silica nanoparticles in drug delivery. In particular, we focus on the stimuli-responsive controlled release systems that are able to respond to intracellular environmental changes, such as pH, ATP, GSH, enzyme, glucose, and H2O2. Moreover, drug delivery induced by exogenous stimuli including temperature, light, magnetic field, ultrasound, and electricity is also summarized. These advanced technologies demonstrate current challenges, and provide a bright future for precision diagnosis and treatment. Keywords: mesoporous silica nanoparticle, drug delivery system, controlled release, stimuli-responsive, chemotherapy

  1. Linear Parameter Varying Control of Induction Motors

    DEFF Research Database (Denmark)

    Trangbæk, Klaus

    The subject of this thesis is the development of linear parameter varying (LPV) controllers and observers for control of induction motors. The induction motor is one of the most common machines in industrial applications. Being a highly nonlinear system, it poses challenging control problems...... for high performance applications. This thesis demonstrates how LPV control theory provides a systematic way to achieve good performance for these problems. The main contributions of this thesis are the application of the LPV control theory to induction motor control as well as various contributions...

  2. Computer applications: Automatic control system for high-voltage accelerator

    International Nuclear Information System (INIS)

    Bryukhanov, A.N.; Komissarov, P.Yu.; Lapin, V.V.; Latushkin, S.T.. Fomenko, D.E.; Yudin, L.I.

    1992-01-01

    An automatic control system for a high-voltage electrostatic accelerator with an accelerating potential of up to 500 kV is described. The electronic apparatus on the high-voltage platform is controlled and monitored by means of a fiber-optic data-exchange system. The system is based on CAMAC modules that are controlled by a microprocessor crate controller. Data on accelerator operation are represented and control instructions are issued by means of an alphanumeric terminal. 8 refs., 6 figs

  3. Extreme challenges on cardiovascular control during gravity transitions

    Science.gov (United States)

    Verheyden, B.; Beckers, F.; Aubert, A. E.

    Introduction. During parabolic flights transient periods of hypergravity and microgravity are created. These periods cause translocations of bodily fluids in the longitudinal axis of the body, leading to altered cardiac preload and afterload. These extreme orthostatic challenges provide a unique platform to study baroreflex-mediated responses of the cardiovascular autonomic control system. This might have important features for the development of a model of cardiovascular deconditioning that is observed in a variety of patient populations. Purpose. Until now, due to methodological restrictions, most studies have been concentrating on the analysis of cardiovascular variability in time domain. The purpose of this study is to evaluate heart rate variability (HRV) and blood pressure variability (BPV) simultaneously, using frequency domain analysis techniques (low frequency power (LF: 0.04-0.15 Hz); high frequency power (HF: 0.16-0.4 Hz)), providing additional information about cardiac and vasomotor sympathetic modulation during gravity transitions. Methods. 12 healthy non-medicated volunteers (age = 24 ± 2.5 yr) underwent continuous ECG and blood pressure (BP) recordings during the 32nd and 34th parabolic flight campaign organized by ESA. The subjects performed 15 parabolas in supine and 15 parabolas in standing position. 5 transient gravity phases were abstracted; phase 1 and 5: before and after the parabola (1G); phase 2 and 4: at the ascending and descending leg of the parabola (2G); phase 3: at the apex of the parabola (0g). Phase 2, 3 and 4 last 20 seconds. Results. No significant differences were found in HRV and BPV parameters in supine position between the different gravity phases. In standing position, mean RR- interval was higher during 0G (900 ± 103 ms) compared to 1G (700 ± 87 ms) and 2G (600 ± 94 ms). Mean arterial BP remained relatively constant during 0G but tended to decrease during 2G (102 ± 2 mmHg vs. 105 ± 3 mmHg). Positive correlations were

  4. Parallel optical control of spatiotemporal neuronal spike activity using high-frequency digital light processingtechnology

    Directory of Open Access Journals (Sweden)

    Jason eJerome

    2011-08-01

    Full Text Available Neurons in the mammalian neocortex receive inputs from and communicate back to thousands of other neurons, creating complex spatiotemporal activity patterns. The experimental investigation of these parallel dynamic interactions has been limited due to the technical challenges of monitoring or manipulating neuronal activity at that level of complexity. Here we describe a new massively parallel photostimulation system that can be used to control action potential firing in in vitro brain slices with high spatial and temporal resolution while performing extracellular or intracellular electrophysiological measurements. The system uses Digital-Light-Processing (DLP technology to generate 2-dimensional (2D stimulus patterns with >780,000 independently controlled photostimulation sites that operate at high spatial (5.4 µm and temporal (>13kHz resolution. Light is projected through the quartz-glass bottom of the perfusion chamber providing access to a large area (2.76 x 2.07 mm2 of the slice preparation. This system has the unique capability to induce temporally precise action potential firing in large groups of neurons distributed over a wide area covering several cortical columns. Parallel photostimulation opens up new opportunities for the in vitro experimental investigation of spatiotemporal neuronal interactions at a broad range of anatomical scales.

  5. Stabilization and trajectory tracking control for underactuated

    Indian Academy of Sciences (India)

    The control of quadrotor helicopter has been a great challenge for control engineers and researchers since quadrotor is an underactuated and a highly unstable nonlinear system. In this paper, the dynamic model of quadrotor has been derived and a so-called robust optimal backstepping control (ROBC) is designed to ...

  6. Perceived parental affectionless control is associated with high neuroticism

    Directory of Open Access Journals (Sweden)

    Takahashi N

    2017-04-01

    Full Text Available Nana Takahashi, Akihito Suzuki, Yoshihiko Matsumoto, Toshinori Shirata, Koichi Otani Department of Psychiatry, Yamagata University School of Medicine, Yamagata, Japan Objective: Depressed patients are prone to perceive that they were exposed to affectionless control by parents. Meanwhile, high neuroticism is a well-established risk factor for developing depression. Therefore, this study examined whether perceived parental affectionless control is associated with high neuroticism.Methods: The subjects were 664 healthy Japanese volunteers. Perceived parental care and protection were assessed by the Parental Bonding Instrument. Parental rearing was categorized into either optimal parenting (high care/low protection or three dysfunctional parenting styles including affectionless control (low care/high protection. Neuroticism was evaluated by the NEO Personality Inventory-Revised.Results: The subjects with paternal affectionless control had higher neuroticism scores than those with paternal optimal parenting. Similar tendency was observed in maternal rearing. Neuroticism scores increased in a stepwise manner with respect to the increase in the number of parents with affectionless control.Conclusion: The present study shows that perceived parental affectionless control is associated with high neuroticism, suggesting that this parental style increases neuroticism in recipients. Keywords: parenting, attachment, personality, vulnerability, depression, PBI, NEO PI-R

  7. Propulsion challenges for a 21st century economically viable, environmentally compatible High-Speed Civil Transport

    Science.gov (United States)

    Shaw, Robert J.

    1991-01-01

    Recent NASA funded studies suggest an opportunity exists for a 21st Century High Speed Civil Transport (HSCT) to become part of the international air transportation system. However, before this opportunity for high speed travel can be realized, certain environmental and economic barrier issues must be overcome. These challenges are outlined. Research activities which NASA has planned to address these barrier issues and provide a technology base to allow the U.S. manufacturers to make an informed go/no go decision on developing an HSCT are discussed.

  8. Challenges in obesity research.

    Science.gov (United States)

    Palou, Andreu; Bonet, M Luisa

    2013-09-01

    Obesity is the main nutritional problem and one of the most important health problems in developed societies. Central to the challenge of obesity prevention and management is a thoroughly understanding of its determinants. Multiple socio-cultural, socio-economic, behavioural and biological factors--often interrelated and many of them still unknown or poorly understood--can contribute to the establishment and perpetuation of obese phenotypes. Here, we address current research challenges regarding basic aspects of obesity and emerging science for its control, including brown adipose tissue thermogenesis and browning of white fat as possible therapeutic targets for obesity, the influence of the microbioma, and genetics, epigenetics, nutrigenomics and nutrigenetics of obesity. We also highlight hot topics in relation to food and lifestyle as determinants of obesity, including the brain mechanisms underlying environmental motivation to eat, the biological control of spontaneous physical activity, the possible role of concrete foods and food components, and the importance of early life nutrition and environment. Challenges regarding the connections of obesity with other alterations and pathologies are also briefly addressed, as well as social and economical challenges in relation to healthy food production and lifestyle for the prevention of obesity, and technological challenges in obesity research and management. The objective is to give a panoramic of advances accomplished and still ahead relevant to the different stakeholders engaged in understanding and combating obesity. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  9. Experimental and Field Results Regarding Immunity Induced by a Recombinant Turkey Herpesvirus H5 Vector Vaccine Against H5N1 and Other H5 Highly Pathogenic Avian Influenza Virus Challenges.

    Science.gov (United States)

    Gardin, Yannick; Palya, Vilmos; Dorsey, Kristi Moore; El-Attrache, John; Bonfante, Francesco; Wit, Sjaak de; Kapczynski, Darrell; Kilany, Walid Hamdy; Rauw, Fabienne; Steensels, Mieke; Soejoedono, Retno D

    2016-05-01

    Vaccination against H5N1 highly pathogenic avian influenza (AI) virus (HPAIV) is one of the possible complementary means available for affected countries to control AI when the disease has become, or with a high risk of becoming, endemic. Efficacy of the vaccination against AI relies essentially, but not exclusively, on the capacity of the vaccine to induce immunity against the targeted virus (which is prone to undergo antigenic variations), as well as its capacity to overcome interference with maternal immunity transmitted by immunized breeding hens to their progeny. This property of the vaccine is a prerequisite for its administration at the hatchery, which assures higher and more reliable vaccine coverage of the populations than vaccination at the farm. A recombinant vector vaccine (Vectormune® AI), based on turkey herpesvirus expressing the hemagglutinin gene of an H5N1 HPAIV as an insert, has been used in several experiments conducted in different research laboratories, as well as in controlled field trials. The results have demonstrated a high degree of homologous and cross protection against different genetic clades of the H5N1 HPAIV. Furthermore, vaccine-induced immunity was not impaired by the presence of passive immunity, but on the contrary, cumulated with it for improved early protection. The demonstrated levels of protection against the different challenge viruses exhibited variations in terms of postchallenge mortality, as well as challenge virus shedding. The data presented here highlight the advantages of this vaccine as a useful and reliable tool to complement biosecurity and sanitary policies for better controlling the disease due to HPAIV of H5 subtypes, when the vaccination is applied as a control measure.

  10. Challenge Study: A Project-Based Learning on a Wireless Communication System at Technical High School

    Science.gov (United States)

    Terasawa, Ikuo

    2016-01-01

    The challenge study is a project based learning curriculum at Technical High School aimed at the construction of a wireless communication system. The first period was engineering issues in the construction of an artificial satellite and the second period was a positional locating system based on the general purpose wire-less device--ZigBee device.…

  11. A Morphing Radiator for High-Turndown Thermal Control of Crewed Space Exploration Vehicles

    Science.gov (United States)

    Cognata, Thomas J.; Hardtl, Darren; Sheth, Rubik; Dinsmore, Craig

    2015-01-01

    Spacecraft designed for missions beyond low earth orbit (LEO) face a difficult thermal control challenge, particularly in the case of crewed vehicles where the thermal control system (TCS) must maintain a relatively constant internal environment temperature despite a vastly varying external thermal environment and despite heat rejection needs that are contrary to the potential of the environment. A thermal control system is in other words required to reject a higher heat load to warm environments and a lower heat load to cold environments, necessitating a quite high turndown ratio. A modern thermal control system is capable of a turndown ratio of on the order of 12:1, but for crew safety and environment compatibility these are massive multi-loop fluid systems. This paper discusses the analysis of a unique radiator design which employs the behavior of shape memory alloys (SMA) to vary the turndown of, and thus enable, a single-loop vehicle thermal control system for space exploration vehicles. This design, a morphing radiator, varies its shape in response to facesheet temperature to control view of space and primary surface emissivity. Because temperature dependence is inherent to SMA behavior, the design requires no accommodation for control, instrumentation, nor power supply in order to operate. Thermal and radiation modeling of the morphing radiator predict a turndown ranging from 11.9:1 to 35:1 independent of TCS configuration. Stress and deformation analyses predict the desired morphing behavior of the concept. A system level mass analysis shows that by enabling a single loop architecture this design could reduce the TCS mass by between 139 kg and 225 kg. The concept is demonstrated in proof-of-concept benchtop tests.

  12. High-frequency, three-phase current controller implementation in an FPGA

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, M.; Round, S. D.; Kolar, J. W.

    2008-07-01

    Three phase rectifiers with switching frequencies of 500 kHz or more require high speed current controllers. At such high switching frequencies analog controllers as well as high speed digital signal processing (DSP) systems have limited performance. In this paper, two high speed current controller implementations using two different field-programmable gate arrays (FPGA) - one for switching frequencies up to 1 MHz and one for switching frequencies beyond 1 MHz - are presented to overcome this performance limitation. Starting with the digital system design all the blocks of the signal chain, containing analog-to-digital (A/D) interface, digital controller implementation using HW-multipliers and implementation of a novel high speed, high resolution pulse width modulation (PWM) are discussed and compared. Final measurements verify the performance of the controllers. (author)

  13. The Challenging Experience Questionnaire: Characterization of challenging experiences with psilocybin mushrooms

    Science.gov (United States)

    Barrett, Frederick S.; Bradstreet, Matthew P.; Leoutsakos, Jeannie-Marie S.; Johnson, Matthew W.; Griffiths, Roland R.

    2017-01-01

    Acute adverse psychological reactions to classic hallucinogens (“bad trips”, or “challenging experiences”), while usually benign with proper screening, preparation, and support in controlled settings, remain a safety concern in uncontrolled settings (such as illicit use contexts). Anecdotal and case reports suggest potential adverse acute symptoms including affective (panic, depressed mood), cognitive (confusion, feelings of losing sanity), and somatic (nausea, heart palpitation) symptoms. Responses to items from several hallucinogen-sensitive questionnaires (Hallucinogen Rating Scale, the States of Consciousness Questionnaire, and the 5-Dimensional Altered States of Consciousness questionnaire) in an internet survey of challenging experiences with the classic hallucinogen psilocybin were used to construct and validate a Challenging Experience Questionnaire (CEQ). The stand-alone CEQ was then validated in a separate sample. Seven CEQ factors (grief, fear, death, insanity, isolation, physical distress, and paranoia) provide a phenomenological profile of challenging aspects of experiences with psilocybin. Factor scores were associated with the difficulty, meaningfulness, spiritual significance, and change in well-being attributed to the challenging experiences. The factor structure did not differ based on gender or prior struggle with anxiety or depression. The CEQ provides a basis for future investigation of predictors and outcomes of challenging experiences with psilocybin, and should be explored as a measure of challenging experiences with the broad class of classic hallucinogens. PMID:27856683

  14. Competitive pricing and the challenge of cost control in medicare.

    Science.gov (United States)

    Coulam, Robert F; Feldman, Roger D; Dowd, Bryan E

    2011-08-01

    The Medicare program faces a serious challenge: it must find ways to control costs but must do so through a system of congressional oversight that necessarily limits its choices. We look at one approach to prudent purchasing - competitive pricing - that Medicare has attempted many times and in various ways since the beginning of the program, and in all but one case unsuccessfully due to the politics of provider opposition working through Congress and the courts. We look at some related efforts to change Medicare pricing to explore when the program has been successful in making dramatic changes in how it pays for health care. A set of recommendations emerges for ways to respond to the impediments of law and politics that have obstructed change to more efficient payment methods. Except in unusual cases, competitive pricing threatens too many stakeholders in too many ways for key political actors to support it. But an unusual case may arise in the coming Medicare fiscal crisis, a crisis related in part to the prices Medicare pays. At that point, competitive pricing may look less like a problem and more like a solution coming at a time when the system badly needs one.

  15. Design and Simulation of a PID Controller for Motion Control Systems

    Science.gov (United States)

    Hassan Abdullahi, Zakariyya; Danzomo, Bashir Ahmed; Suleiman Abdullahi, Zainab

    2018-04-01

    Motion control system plays important role in many industrial applications among which are in robot system, missile launching, positioning systems etc. However, the performance requirement for these applications in terms of high accuracy, high speed, insignificant or no overshoot and robustness have generated continuous challenges in the field of motion control system design and implementation. To compensate this challenge, a PID controller was design using mathematical model of a DC motor based on classical root-locus approach. The reason for adopting root locus design is to remodel the closed-loop response by putting the closed-loop poles of the system at desired points. Adding poles and zeros to the initial open-loop transfer function through the controller provide a way to transform the root locus in order to place the closed-loop poles at the required points. This process can also be used for discrete-time models. The Advantages of root locus over other methods is that, it gives the better way of pinpointing the parameters and can easily predict the fulfilment of the whole system. The controller performance was simulated using MATLAB code and a reasonable degree of accuracy was obtained. Implementation of the proposed model was conducted using-Simulink and the result obtained shows that the PID controller met the transient performance specifications with both settling time and overshoot less than 0.1s and 5% respectively. In terms of steady state error, the PID controller gave good response for both step input and ramp.

  16. Metrology challenges for high-rate nanomanufacturing of polymer structures

    Science.gov (United States)

    Mead, Joey; Barry, Carol; Busnaina, Ahmed; Isaacs, Jacqueline

    2012-10-01

    The transfer of nanoscience accomplishments into commercial products is hindered by the lack of understanding of barriers to nanoscale manufacturing. We have developed a number of nanomanufacturing processes that leverage available high-rate plastics fabrication technologies. These processes include directed assembly of a variety of nanoelements, such as nanoparticles and nanotubes, which are then transferred onto a polymer substrate for the fabrication of conformal/flexible electronic materials, among other applications. These assembly processes utilize both electric fields and/or chemical functionalization. Conducting polymers and carbon nanotubes have been successfully transferred to a polymer substrate in times less than 5 minutes, which is commercially relevant and can be utilized in a continuous (reel to reel/roll to roll) process. Other processes include continuous high volume mixing of nanoelements (CNTs, etc) into polymers, multi-layer extrusion and 3D injection molding of polymer structures. These nanomanufacturing processes can be used for wide range of applications, including EMI shielding, flexible electronics, structural materials, and novel sensors (specifically for chem/bio detection). Current techniques to characterize the quality and efficacy of the processes are quite slow. Moreover, the instrumentation and metrology needs for these manufacturing processes are varied and challenging. Novel, rapid, in-line metrology to enable the commercialization of these processes is critically needed. This talk will explore the necessary measurement needs for polymer based nanomanufacturing processes for both step and continuous (reel to reel/roll to roll) processes.

  17. Stable Plastid Transformation for High-Level Recombinant Protein Expression: Promises and Challenges

    Directory of Open Access Journals (Sweden)

    Meili Gao

    2012-01-01

    Full Text Available Plants are a promising expression system for the production of recombinant proteins. However, low protein productivity remains a major obstacle that limits extensive commercialization of whole plant and plant cell bioproduction platform. Plastid genetic engineering offers several advantages, including high levels of transgenic expression, transgenic containment via maternal inheritance, and multigene expression in a single transformation event. In recent years, the development of optimized expression strategies has given a huge boost to the exploitation of plastids in molecular farming. The driving forces behind the high expression level of plastid bioreactors include codon optimization, promoters and UTRs, genotypic modifications, endogenous enhancer and regulatory elements, posttranslational modification, and proteolysis. Exciting progress of the high expression level has been made with the plastid-based production of two particularly important classes of pharmaceuticals: vaccine antigens, therapeutic proteins, and antibiotics and enzymes. Approaches to overcome and solve the associated challenges of this culture system that include low transformation frequencies, the formation of inclusion bodies, and purification of recombinant proteins will also be discussed.

  18. Rift Valley fever: current challenges and future prospects

    Directory of Open Access Journals (Sweden)

    Himeidan YE

    2016-03-01

    Full Text Available Yousif E Himeidan Vector Control Unit, Africa Technical Research Centre, Vector Health International, Arusha, Tanzania Abstract: Rift Valley fever (RVF is a zoonotic, mosquito-borne viral disease that affects human health and causes significant losses in the livestock industry. Recent outbreaks have led to severe human infections with high mortality rates. There are many challenges to applying effective preventive and control measures, including weak infrastructure of health facilities, lack of capacity and support systems for field logistics and communication, access to global expert organizations, and insufficient information on the epidemiological and reservoir status of the RVF virus. The health systems in East African countries are underdeveloped, with gaps in adaptability to new, more accurate and rapid techniques, and well-trained staff that affect their capacity to monitor and evaluate the disease. Surveillance and response systems are inadequate in providing accurate information in a timely manner for decision making to deal with the scope of interrupting the disease transmission by applying mass animal vaccination, and other preventive measures at the early stage of an outbreak. The historical vaccines are unsuitable for use in newborn and gestating livestock, and the recent ones require a booster and annual revaccination. Future live-attenuated RVF vaccines should possess lower safety concerns regardless of the physiologic state of the animal, and provide rapid and long-term immunity after a single dose of vaccination. In the absence of an effective vaccination program, prevention and control measures must be immediately undertaken after an alert is generated. These measures include enforcing and adapting standard protocols for animal trade and movement, extensive vector control, safe disposal of infected animals, and modification of human–animal contact behavior. Directing control efforts on farmers and workers who deal with

  19. High pressure common rail injection system modeling and control.

    Science.gov (United States)

    Wang, H P; Zheng, D; Tian, Y

    2016-07-01

    In this paper modeling and common-rail pressure control of high pressure common rail injection system (HPCRIS) is presented. The proposed mathematical model of high pressure common rail injection system which contains three sub-systems: high pressure pump sub-model, common rail sub-model and injector sub-model is a relative complicated nonlinear system. The mathematical model is validated by the software Matlab and a virtual detailed simulation environment. For the considered HPCRIS, an effective model free controller which is called Extended State Observer - based intelligent Proportional Integral (ESO-based iPI) controller is designed. And this proposed method is composed mainly of the referred ESO observer, and a time delay estimation based iPI controller. Finally, to demonstrate the performances of the proposed controller, the proposed ESO-based iPI controller is compared with a conventional PID controller and ADRC. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  20. Challenges and Opportunities of Very Light High-Performance Electric Drives for Aviation

    Directory of Open Access Journals (Sweden)

    Markus Henke

    2018-02-01

    Full Text Available The demand for alternative fueling methods to reduce the need for fossil fuels is not limited to the electrification of ground vehicles. More-electric and all-electric aircraft pose challenges, with extensive requirements in terms of power density, efficiency, safety, and environmental sustainability. This paper focuses on electrical machines and their components, especially for high-power applications like the main propulsion. The electrical machine is evaluated from different aspects, followed by a closer look at the components and materials to determine the suitability of the current standard materials and advanced technologies. Furthermore, the mechanical and thermal aspects are reviewed, including new and innovative concepts for the cooling of windings and for the use of additive manufacturing. Aircraft have special demands regarding weight and installation space. Following recent developments and looking ahead to the future, the need and the possibilities for light and efficient electrical machines are addressed. All of the approaches and developments presented lead to a better understanding of the challenges to be expected and highlight the upcoming opportunities in electrical machine design for the use of electric motors and generators in future aircraft. Several prototypes of electrical machines for smaller aircraft already exist, such as the electric drive of the Siemens powered Extra 330LE. The focus of this paper is to provide an overview of current technical possibilities and technical interrelations of high performance electric drives for aviation. A 1 MW drive is exemplified to present the possibilities for future drives for airplanes carrying a larger number of passengers. All presented techniques can also be applied to other drive power classes.

  1. Teaching Theory of Mind: A Curriculum for Children with High Functioning Autism, Asperger's Syndrome, and Related Social Challenges

    Science.gov (United States)

    Ordetx, Kirstina

    2012-01-01

    This book provides teachers and other professionals with a highly effective, easy-to-follow curriculum for teaching children with high-functioning autism, Asperger syndrome and related social challenges to relate to and interact with others successfully by developing a solid, basic foundation in Theory of Mind (ToM). Dr. Kirstina Ordetx provides…

  2. Multi-actuation and PI control: A simple recipe for high-speed and large-range atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Soltani Bozchalooi, I., E-mail: isoltani@mit.edu; Youcef-Toumi, K.

    2014-11-15

    High speed atomic force microscopy enables observation of dynamic nano-scale processes. However, maintaining a minimal interaction force between the sample and the probe is challenging at high speed specially when using conventional piezo-tubes. While rigid AFM scanners are operational at high speeds with the drawback of reduced tracking range, multi-actuation schemes have shown potential for high-speed and large-range imaging. Here we present a method to seamlessly incorporate additional actuators into conventional AFMs. The equivalent behavior of the resulting multi-actuated setup resembles that of a single high-speed and large-range actuator with maximally flat frequency response. To achieve this, the dynamics of the individual actuators and their couplings are treated through a simple control scheme. Upon the implementation of the proposed technique, commonly used PI controllers are able to meet the requirements of high-speed imaging. This forms an ideal platform for retroactive enhancement of existing AFMs with minimal cost and without compromise on the tracking range. A conventional AFM with tube scanner is retroactively enhanced through the proposed method and shows an order of magnitude improvement in closed loop bandwidth performance while maintaining large range. The effectiveness of the method is demonstrated on various types of samples imaged in contact and tapping modes, in air and in liquid. - Highlights: • We present a novel method to incorporate extra actuators into conventional AFMs. • A maximally flat frequency response is achieved for the out of plane piezo-motion. • Commonly used PI or PID control is enabled to handle high speed AFM imaging. • An order of magnitude improvement in closed loop bandwidth performance is obtained. • High speed imaging is achieved on a large range piezo-tube.

  3. Multi-actuation and PI control: A simple recipe for high-speed and large-range atomic force microscopy

    International Nuclear Information System (INIS)

    Soltani Bozchalooi, I.; Youcef-Toumi, K.

    2014-01-01

    High speed atomic force microscopy enables observation of dynamic nano-scale processes. However, maintaining a minimal interaction force between the sample and the probe is challenging at high speed specially when using conventional piezo-tubes. While rigid AFM scanners are operational at high speeds with the drawback of reduced tracking range, multi-actuation schemes have shown potential for high-speed and large-range imaging. Here we present a method to seamlessly incorporate additional actuators into conventional AFMs. The equivalent behavior of the resulting multi-actuated setup resembles that of a single high-speed and large-range actuator with maximally flat frequency response. To achieve this, the dynamics of the individual actuators and their couplings are treated through a simple control scheme. Upon the implementation of the proposed technique, commonly used PI controllers are able to meet the requirements of high-speed imaging. This forms an ideal platform for retroactive enhancement of existing AFMs with minimal cost and without compromise on the tracking range. A conventional AFM with tube scanner is retroactively enhanced through the proposed method and shows an order of magnitude improvement in closed loop bandwidth performance while maintaining large range. The effectiveness of the method is demonstrated on various types of samples imaged in contact and tapping modes, in air and in liquid. - Highlights: • We present a novel method to incorporate extra actuators into conventional AFMs. • A maximally flat frequency response is achieved for the out of plane piezo-motion. • Commonly used PI or PID control is enabled to handle high speed AFM imaging. • An order of magnitude improvement in closed loop bandwidth performance is obtained. • High speed imaging is achieved on a large range piezo-tube

  4. Microprocessor-controlled meter of high Q-values

    International Nuclear Information System (INIS)

    Bun'kov, S.N.; Konstantinov, V.I.; Masalov, V.L.; Sevrukova, L.M.; Tokarev, A.D.; Usiv, Yu.V.

    1990-01-01

    The paper describes the functional model of a high-precision microcomputer-controlled test facility for studying the electric and physical parameters of superconducting cavities. The basic unit of the test facility is high-stability retunable RF oscillator. It is designed following the scheme of the frequency phase tuning using standard equipment. The systematic error in measuring the loaded Q-value of reentrant cavities is not larger than 5%. A dedicated built-in microcomputer is used to control the measuring test facility and to make the commutations required. 2 refs.; 2 figs

  5. Sustained Malaria Control Over an 8-Year Period in Papua New Guinea: The Challenge of Low-Density Asymptomatic Plasmodium Infections.

    Science.gov (United States)

    Koepfli, Cristian; Ome-Kaius, Maria; Jally, Shadrach; Malau, Elisheba; Maripal, Samuel; Ginny, Jason; Timinao, Lincoln; Kattenberg, Johanna Helena; Obadia, Thomas; White, Michael; Rarau, Patricia; Senn, Nicolas; Barry, Alyssa E; Kazura, James W; Mueller, Ivo; Robinson, Leanne J

    2017-12-12

    The scale-up of effective malaria control in the last decade has resulted in a substantial decline in the incidence of clinical malaria in many countries. The effects on the proportions of asymptomatic and submicroscopic infections and on transmission potential are yet poorly understood. In Papua New Guinea, vector control has been intensified since 2008, and improved diagnosis and treatment was introduced in 2012. Cross-sectional surveys were conducted in Madang Province in 2006 (with 1280 survey participants), 2010 (with 2117 participants), and 2014 (with 2516 participants). Infections were quantified by highly sensitive quantitative polymerase chain reaction (PCR) analysis, and gametocytes were quantified by reverse-transcription qPCR analysis. Plasmodium falciparum prevalence determined by qPCR decreased from 42% in 2006 to 9% in 2014. The P. vivax prevalence decreased from 42% in 2006 to 13% in 2010 but then increased to 20% in 2014. Parasite densities decreased 5-fold from 2006 to 2010; 72% of P. falciparum and 87% of P. vivax infections were submicroscopic in 2014. Gametocyte density and positivity correlated closely with parasitemia, and population gametocyte prevalence decreased 3-fold for P. falciparum and 29% for P. vivax from 2010 to 2014. Sustained control has resulted in reduced malaria transmission potential, but an increasing proportion of gametocyte carriers are asymptomatic and submicroscopic and represent a challenge to malaria control. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  6. Managing Stress to Control High Blood Pressure

    Science.gov (United States)

    ... Aortic Aneurysm More Managing Stress to Control High Blood Pressure Updated:Jan 29,2018 The importance of stress ... This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  7. Building a Grad Nation: Progress and Challenge in Ending the High School Dropout Epidemic. Annual Update, 2010-2011

    Science.gov (United States)

    Balfanz, Robert; Bridgeland, John M.; Fox, Joanna Hornig; Moore, Laura A.

    2011-01-01

    America continues to make progress in meeting its high school dropout challenge. Leaders in education, government, nonprofits and business have awakened to the individual, social and economic costs of the dropout crisis and are working together to solve it. This year, all states, districts, and schools are required by law to calculate high school…

  8. Visceral leishmaniasis in large Brazilian cities: challenges for control

    Directory of Open Access Journals (Sweden)

    Claudia Di Lorenzo Oliveira

    2008-12-01

    Full Text Available The objectives of this article were to discuss the rapid spread of visceral leishmaniasis in urban areas of Brazil and to raise practical questions and perspectives related to control of the disease. Among the proposed methods, the elimination of seropositive dogs is the most controversial and least accepted by society. Its impact on incidence rates varies among studies (positive in some and relatively unimportant in others. Treatment of infected dogs, although widespread in veterinary practice, is based on studies with weak scientific evidence. Insecticide spraying of areas is more acceptable to the population, but is costly and operationally difficult. Intra and inter-urban factors have scarcely been studied and may affect control of the disease. Finally, the article discusses the use of deltamethrin-impregnated dog collars and vaccines, with high expectations for impact on disease transmission, although no product currently available on the market has been fully evaluated, so that further studies are required.

  9. External cues challenging the internal appetite control system-Overview and practical implications.

    Science.gov (United States)

    Bilman, Els; van Kleef, Ellen; van Trijp, Hans

    2017-09-02

    Inadequate regulation of food intake plays an important role in the development of overweight and obesity, and is under the influence of both the internal appetite control system and external environmental cues. Especially in environments where food is overly available, external cues seem to override and/or undermine internal signals, which put severe challenges on the accurate regulation of food intake. By structuring these external cues around five different phases in the food consumption process this paper aims to provide an overview of the wide range of external cues that potentially facilitate or hamper internal signals and with that influence food intake. For each of the five phases of the food consumption process, meal initiation, meal planning, consumption phase, end of eating episode and time till next meal, the most relevant internal signals are discussed and it is explained how specific external cues exert their influence.

  10. Challenges in process integration of catalytic DC plasma synthesis of vertically aligned carbon nanofibres

    International Nuclear Information System (INIS)

    Melechko, Anatoli V; Pearce, Ryan C; Hensley, Dale K; Simpson, Michael L; McKnight, Timothy E

    2011-01-01

    The ability to synthesize free-standing, individual carbon nanofibres (CNFs) aligned perpendicularly to a substrate has enabled fabrication of a large array of devices with nanoscale functional elements, including electron field emission sources, electrochemical probes, neural interface arrays, scanning probes, gene delivery arrays and many others. This was made possible by development of a catalytic plasma process, with DC bias directing the alignment of nanofibres. Successful implementation of prototypical devices has uncovered numerous challenges in the integration of this synthesis process as one of the steps in device fabrication. This paper is dedicated to these engineering and fundamental difficulties that hinder further device development. Relatively high temperature for catalytic synthesis, electrical conductivity of the substrate to maintain DC discharge and other difficulties place restrictions on substrate material. Balancing non-catalytic carbon film deposition and substrate etching, non-uniformity of plasma due to growth of the high aspect ratio structures, plasma instabilities and other factors lead to challenges in controlling the plasma. Ultimately, controlling the atomistic processes at the catalyst nanoparticle (NP) and the behaviour of the NP is the central challenge of plasma nanosynthesis of vertically aligned CNFs.

  11. Electronics and triggering challenges for the CMS High Granularity Calorimeter for HL-LHC

    CERN Document Server

    Borg, Johan

    2017-01-01

    The High Granularity Calorimeter (HGCAL) is presently being designedto replace the CMS endcap calorimeters for the HighLuminosity phase at LHC. It will feature six million silicon sensor channelsand 52 longitudinal layers. The requirements for the frontendelectronics include a 0.3 fC-10 pC dynamic range, low noise (2000 e-) and low power consumption (10 mW /channel).In addition, the HGCAL will perform 50 ps resolution time of arrivalmeasurements to combat the effect of the large number of interactions taking placeat each bunch crossing, and will transmit both triggered readoutfrom on-detector buffer memory and reduced resolution real-time trigger data.We present the challenges related to the frontend electronics, data transmissionand off-detector trigger preprocessing that must be overcome, and the designconcepts currently being pursued.

  12. The ILC global control system

    International Nuclear Information System (INIS)

    Carwardine, J.; Arnold, N.; Lenkszus, F.; Saunders, C.; Rehlich, K.; Simrock, S.; Banerjee, B.; Chase, B.; Gottschalk, E.; Joireman, P.; Kasley, P.; Lackey, S.; McBride, P.; Pavlicek, V.; Patrick, J.; Votava, M.; Wolbers, S.; Furukawa, K.; Michizono, S.; Larsen, R.S.; Downing, R.

    2008-01-01

    The scale and performance parameters of the ILC require new thinking in regards to control system design. This design work has begun quite early in comparison to most accelerator projects, with the goal of uniquely high overall accelerator availability. Among the design challenges are high control system availability, precision timing and rf phase reference distribution, standardizing of interfaces, operability, and maintainability. We present the current state of the design and take a prospective look at ongoing research and development projects.

  13. Design of embedded control system for high-power tetrode modulator

    International Nuclear Information System (INIS)

    Tu Rui; Yao Lieying; Xuan Weimin

    2010-01-01

    The design of embedded control system for the high-power tetrode modulator and its test results are given. This control system is a closed-loop feedback system based on the DSP and embedded into the high-voltage modulator. A new modified method of VF fiber transmission is used in the embedded control system. The new method improves the speed of the transmission of feedback system. The results of the experiment demonstrate that the embedded feedback control system greatly increases the response speed of the whole system and improves the performance of the high-power tetrode on the HL-2A tokamak. This embedded feedback control system greatly simplifies the complexity of the original centralized control system. The operation of the control system is reliable. (authors)

  14. Shape-controlled porous nanocarbons for high performance supercapacitors

    KAUST Repository

    Chén, Wěi

    2014-01-01

    Porous activated nanocarbons with well-controlled dimensionality and morphology (i.e. 0D activated carbon nanoparticles, 1D activated carbon nanotubes, and 2D activated carbon nanosheets) were derived successfully from different template-induced polyaniline nanostructures by facile carbonization and activation processes. The obtained nanocarbons show large specific surface areas (1332-2005 m2 g-1), good conductivities, and highly porous nanoscale architectures. The supercapacitors fabricated using the shape-controlled nanocarbons exhibit high specific capacitance, excellent rate capability, and superior long-term cycling stability in both aqueous and ionic liquid electrolytes. More importantly, a very high energy density of 50.5 W h kg-1 with a power density of 17.4 kW kg-1 can be obtained from the activated carbon nanotube based supercapacitors in an ionic liquid electrolyte (with a charge time of ∼10 s), making the shape-controlled nanocarbons promising candidates for high-performance energy storage devices. © 2014 the Partner Organisations.

  15. BigData and computing challenges in high energy and nuclear physics

    Science.gov (United States)

    Klimentov, A.; Grigorieva, M.; Kiryanov, A.; Zarochentsev, A.

    2017-06-01

    In this contribution we discuss the various aspects of the computing resource needs experiments in High Energy and Nuclear Physics, in particular at the Large Hadron Collider. This will evolve in the future when moving from LHC to HL-LHC in ten years from now, when the already exascale levels of data we are processing could increase by a further order of magnitude. The distributed computing environment has been a great success and the inclusion of new super-computing facilities, cloud computing and volunteering computing for the future is a big challenge, which we are successfully mastering with a considerable contribution from many super-computing centres around the world, academic and commercial cloud providers. We also discuss R&D computing projects started recently in National Research Center ``Kurchatov Institute''

  16. BigData and computing challenges in high energy and nuclear physics

    International Nuclear Information System (INIS)

    Klimentov, A.; Grigorieva, M.; Kiryanov, A.; Zarochentsev, A.

    2017-01-01

    In this contribution we discuss the various aspects of the computing resource needs experiments in High Energy and Nuclear Physics, in particular at the Large Hadron Collider. This will evolve in the future when moving from LHC to HL-LHC in ten years from now, when the already exascale levels of data we are processing could increase by a further order of magnitude. The distributed computing environment has been a great success and the inclusion of new super-computing facilities, cloud computing and volunteering computing for the future is a big challenge, which we are successfully mastering with a considerable contribution from many super-computing centres around the world, academic and commercial cloud providers. We also discuss R and D computing projects started recently in National Research Center ''Kurchatov Institute''

  17. Big Data Challenges of High-Dimensional Continuous-Time Mean-Variance Portfolio Selection and a Remedy.

    Science.gov (United States)

    Chiu, Mei Choi; Pun, Chi Seng; Wong, Hoi Ying

    2017-08-01

    Investors interested in the global financial market must analyze financial securities internationally. Making an optimal global investment decision involves processing a huge amount of data for a high-dimensional portfolio. This article investigates the big data challenges of two mean-variance optimal portfolios: continuous-time precommitment and constant-rebalancing strategies. We show that both optimized portfolios implemented with the traditional sample estimates converge to the worst performing portfolio when the portfolio size becomes large. The crux of the problem is the estimation error accumulated from the huge dimension of stock data. We then propose a linear programming optimal (LPO) portfolio framework, which applies a constrained ℓ 1 minimization to the theoretical optimal control to mitigate the risk associated with the dimensionality issue. The resulting portfolio becomes a sparse portfolio that selects stocks with a data-driven procedure and hence offers a stable mean-variance portfolio in practice. When the number of observations becomes large, the LPO portfolio converges to the oracle optimal portfolio, which is free of estimation error, even though the number of stocks grows faster than the number of observations. Our numerical and empirical studies demonstrate the superiority of the proposed approach. © 2017 Society for Risk Analysis.

  18. Nursing Education in High Blood Pressure Control. Report of the Task Force on the Role of Nursing in High Blood Pressure Control.

    Science.gov (United States)

    National Institutes of Health (DHEW), Bethesda, MD. High Blood Pressure Information Center.

    This curriculum guide on high blood pressure (hypertension) for nursing educators has five sections: (1) Introduction and Objectives provides information regarding the establishment and objectives of the National Task Force on the Role of Nursing in High Blood Pressure Control and briefly discusses nursing's role in hypertension control; (2) Goals…

  19. Controlling high-throughput manufacturing at the nano-scale

    Science.gov (United States)

    Cooper, Khershed P.

    2013-09-01

    Interest in nano-scale manufacturing research and development is growing. The reason is to accelerate the translation of discoveries and inventions of nanoscience and nanotechnology into products that would benefit industry, economy and society. Ongoing research in nanomanufacturing is focused primarily on developing novel nanofabrication techniques for a variety of applications—materials, energy, electronics, photonics, biomedical, etc. Our goal is to foster the development of high-throughput methods of fabricating nano-enabled products. Large-area parallel processing and highspeed continuous processing are high-throughput means for mass production. An example of large-area processing is step-and-repeat nanoimprinting, by which nanostructures are reproduced again and again over a large area, such as a 12 in wafer. Roll-to-roll processing is an example of continuous processing, by which it is possible to print and imprint multi-level nanostructures and nanodevices on a moving flexible substrate. The big pay-off is high-volume production and low unit cost. However, the anticipated cost benefits can only be realized if the increased production rate is accompanied by high yields of high quality products. To ensure product quality, we need to design and construct manufacturing systems such that the processes can be closely monitored and controlled. One approach is to bring cyber-physical systems (CPS) concepts to nanomanufacturing. CPS involves the control of a physical system such as manufacturing through modeling, computation, communication and control. Such a closely coupled system will involve in-situ metrology and closed-loop control of the physical processes guided by physics-based models and driven by appropriate instrumentation, sensing and actuation. This paper will discuss these ideas in the context of controlling high-throughput manufacturing at the nano-scale.

  20. PC-based control of a high-voltage injector

    International Nuclear Information System (INIS)

    Constantin, F.

    1998-01-01

    The stability of high voltage injectors is one of the major problems in any accelerator system. Most of the troubles encountered in the normal operation of an accelerator are connected with the ion source and associated high voltage platforms, regardless of the source or high voltage generator type. The quality of the ion beam injected in the accelerator strongly depends on the power supplies used in the injector and on the ability to control the non-electrical parameters (gas-flow, temperature, etc.). A wide used method in controlling is based on optical links between high-voltage platform and computer, the adjustments being more or less automated. Although the method mentioned above can be still useful in injector control, a different approach is presented in this work, i.e., the computer itself is placed inside the high-voltage terminal. Only one optical link is still necessary to connect this computer with an user-friendly host at ground potential. Requirements: - varying and monitoring the filament current; - gas flow control in the ion source; - reading the vacuum values; - current and voltage control for the anodic, magnet, extraction, suppression and lens' sources. Even in the high voltage terminal there are compartments with different voltages regardless the floating ground. In our injector the extraction voltage is applied on the top of the ion source including the filament and the anodic voltage. The extraction voltage is of maximum 30 kV. In this situation a second optical link is required to transfer the control for the anodic and magnet source power supply assuming the dedicated computer on the floating ground. One PC is placed inside the high voltage terminal and one PC outside the injector. The optical link (more precisely two optical wires) connects the serial ports. The inside computer is equipped with two multipurpose ADC/DAC and digital I/O card. They permit to read or output DC levels ranging between 0 to 10 volts or TTL signals. The filament

  1. Informal learning of temporary agency workers in low-skill jobs: The role of self-profiling, career control, and job challenge

    NARCIS (Netherlands)

    Preenen, P.; Verbiest, S.; van Vianen, A.; van Wijk, E.

    2015-01-01

    Purpose: The purpose of this paper is to develop and investigate the idea that self-profiling and career control by temporary agency workers (TAWs) in low-skill jobs are positively related to informal learning and that this relationship is mediated by job challenge. Design/methodology/approach: An

  2. Informal learning of temporary agency workers in low-skill jobs : the role of self-profiling, career control and job challenge

    NARCIS (Netherlands)

    Preenen, P.T.Y.; Verbiest, S.; Vianen, A. van; Wijk, E. van

    2015-01-01

    Purpose. The purpose of this paper is to develop and investigate the idea that self-profiling and career control by temporary agency workers (TAWs) in low-skill jobs are positively related to informal learning and that this relationship is mediated by job challenge. Design/methodology/approach. An

  3. Analysis of fatigue reliability for high temperature and high pressure multi-stage decompression control valve

    Science.gov (United States)

    Yu, Long; Xu, Juanjuan; Zhang, Lifang; Xu, Xiaogang

    2018-03-01

    Based on stress-strength interference theory to establish the reliability mathematical model for high temperature and high pressure multi-stage decompression control valve (HMDCV), and introduced to the temperature correction coefficient for revising material fatigue limit at high temperature. Reliability of key dangerous components and fatigue sensitivity curve of each component are calculated and analyzed by the means, which are analyzed the fatigue life of control valve and combined with reliability theory of control valve model. The impact proportion of each component on the control valve system fatigue failure was obtained. The results is shown that temperature correction factor makes the theoretical calculations of reliability more accurate, prediction life expectancy of main pressure parts accords with the technical requirements, and valve body and the sleeve have obvious influence on control system reliability, the stress concentration in key part of control valve can be reduced in the design process by improving structure.

  4. Export controls on high technology

    Energy Technology Data Exchange (ETDEWEB)

    Frank, N.K.

    1987-01-01

    A overview of the Export Administration Act of 1979 and subsequent regulations and amendments focuses on how licensing requirements and restrictions against boycott affect high technology exports. The purpose of these controls is to limit the export of technology with possible military applications, as well as to advance US foreign policy and protect the economy without imposing too great a restriction on the principles of free trade. Thus, the act encompasses political, economic, and security goals. Problems of predictability arise when embargoes or other controls are imposed for political or foreign policy reasons without regard to economic impacts. Amendments have attempted to streamline the exporting process, particularly in the area of computer and software licensing.

  5. High performance control strategy for single-phase three-level neutral-point-clamped traction four-quadrant converters

    DEFF Research Database (Denmark)

    Kejian, Song; Konstantinou, Georgios; Jing, Li

    2017-01-01

    Operational data from Chinese railways indicate a number of challenges for traction four-quadrant converter (4QC) control including low-order voltage and current harmonics and reference tracking. A control strategy for a single-phase three-level neutral-point-clamped 4QC employed in the electric...

  6. Very high gravity ethanol fermentation by flocculating yeast under redox potential-controlled conditions

    Directory of Open Access Journals (Sweden)

    Liu Chen-Guang

    2012-08-01

    Full Text Available Abstract Background Very high gravity (VHG fermentation using medium in excess of 250 g/L sugars for more than 15% (v ethanol can save energy consumption, not only for ethanol distillation, but also for distillage treatment; however, stuck fermentation with prolonged fermentation time and more sugars unfermented is the biggest challenge. Controlling redox potential (ORP during VHG fermentation benefits biomass accumulation and improvement of yeast cell viability that is affected by osmotic pressure and ethanol inhibition, enhancing ethanol productivity and yield, the most important techno-economic aspect of fuel ethanol production. Results Batch fermentation was performed under different ORP conditions using the flocculating yeast and media containing glucose of 201 ± 3.1, 252 ± 2.9 and 298 ± 3.8 g/L. Compared with ethanol fermentation by non-flocculating yeast, different ORP profiles were observed with the flocculating yeast due to the morphological change associated with the flocculation of yeast cells. When ORP was controlled at −100 mV, ethanol fermentation with the high gravity (HG media containing glucose of 201 ± 3.1 and 252 ± 2.9 g/L was completed at 32 and 56 h, respectively, producing 93.0 ± 1.3 and 120.0 ± 1.8 g/L ethanol, correspondingly. In contrast, there were 24.0 ± 0.4 and 17.0 ± 0.3 g/L glucose remained unfermented without ORP control. As high as 131.0 ± 1.8 g/L ethanol was produced at 72 h when ORP was controlled at −150 mV for the VHG fermentation with medium containing 298 ± 3.8 g/L glucose, since yeast cell viability was improved more significantly. Conclusions No lag phase was observed during ethanol fermentation with the flocculating yeast, and the implementation of ORP control improved ethanol productivity and yield. When ORP was controlled at −150 mV, more reducing power was available for yeast cells to survive, which in turn improved their viability and VHG

  7. Fault Detection and Load Distribution for the Wind Farm Challenge

    DEFF Research Database (Denmark)

    Borchersen, Anders Bech; Larsen, Jesper Abildgaard; Stoustrup, Jakob

    2014-01-01

    In this paper a fault detection system and a fault tolerant controller for a wind farm model is designed and tested. The wind farm model is taken from the wind farm challenge which is a public available challenge where a wind farm consisting of nine turbines is proposed. The goal of the challenge...... normal and faulty conditions. Thus a fault detection system and a fault tolerant controller has been designed and combined. The fault tolerant control system has then been tested and compared to the reference system and shows improvement on all measures....

  8. Control system for high power laser drilling workover and completion unit

    Science.gov (United States)

    Zediker, Mark S; Makki, Siamak; Faircloth, Brian O; DeWitt, Ronald A; Allen, Erik C; Underwood, Lance D

    2015-05-12

    A control and monitoring system controls and monitors a high power laser system for performing high power laser operations. The control and monitoring system is configured to perform high power laser operation on, and in, remote and difficult to access locations.

  9. Safety analysis - current and future regulatory challenges

    Energy Technology Data Exchange (ETDEWEB)

    Jamieson, T., E-mail: Terry.Jamieson@cnsc-ccsn.gc.ca [Canadian Nuclear Safety Commission, Ottawa, ON (Canada)

    2015-07-01

    'Full text:' The current and future regulatory challenges associated with deterministic safety analysis are reviewed, including: 1. The CNSC's and safety control areas. 2. Traditional safety analysis approach. 3. Experience gained and impact. 4. Current analysis and regulatory approaches. 5. Current status. 6. Complexity and challenges In particular, the technical, regulatory and strategic aspects of these challenges are discussed. (author)

  10. Safety analysis - current and future regulatory challenges

    International Nuclear Information System (INIS)

    Jamieson, T.

    2015-01-01

    'Full text:' The current and future regulatory challenges associated with deterministic safety analysis are reviewed, including: 1. The CNSC's and safety control areas. 2. Traditional safety analysis approach. 3. Experience gained and impact. 4. Current analysis and regulatory approaches. 5. Current status. 6. Complexity and challenges In particular, the technical, regulatory and strategic aspects of these challenges are discussed. (author)

  11. Modeling and control of greenhouse crop growth

    CERN Document Server

    Rodríguez, Francisco; Guzmán, José Luis; Ramírez-Arias, Armando

    2015-01-01

    A discussion of challenges related to the modeling and control of greenhouse crop growth, this book presents state-of-the-art answers to those challenges. The authors model the subsystems involved in successful greenhouse control using different techniques and show how the models obtained can be exploited for simulation or control design; they suggest ideas for the development of physical and/or black-box models for this purpose. Strategies for the control of climate- and irrigation-related variables are brought forward. The uses of PID control and feedforward compensators, both widely used in commercial tools, are summarized. The benefits of advanced control techniques—event-based, robust, and predictive control, for example—are used to improve on the performance of those basic methods. A hierarchical control architecture is developed governed by a high-level multiobjective optimization approach rather than traditional constrained optimization and artificial intelligence techniques.  Reference trajector...

  12. High body mass index is associated with impaired cognitive control.

    Science.gov (United States)

    Sellaro, Roberta; Colzato, Lorenza S

    2017-06-01

    The prevalence of weight problems is increasing worldwide. There is growing evidence that high body mass index (BMI) is associated with frontal lobe dysfunction and cognitive deficits concerning mental flexibility and inhibitory control efficiency. The present study aims at replicating and extending these observations. We compared cognitive control performance of normal weight (BMI task tapping either inhibitory control (Experiment 1) or interference control (Experiment 2). Experiment 1 replicated previous findings that found less efficient inhibitory control in overweight individuals. Experiment 2 complemented these findings by showing that cognitive control impairments associated with high BMI also extend to the ability to resolve stimulus-induced response conflict and to engage in conflict-driven control adaptation. The present results are consistent with and extend previous literature showing that high BMI in young, otherwise healthy individuals is associated with less efficient cognitive control functioning. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Supporting Control Room Operators in Highly Automated Future Power Networks

    DEFF Research Database (Denmark)

    Chen, Minjiang; Catterson, Victoria; Syed, Mazheruddin

    2017-01-01

    Operating power systems is an extremely challenging task, not least because power systems have become highly interconnected, as well as the range of network issues that can occur. It is therefore a necessity to develop decision support systems and visualisation that can effectively support the hu...... the human operators for decisionmaking in the complex and dynamic environment of future highly automated power system. This paper aims to investigate the decision support functions associated with frequency deviation events for the proposed Web of Cells concept....

  14. A Customizable Platform for High-availability Monitoring, Control and Data Distribution at CERN

    CERN Document Server

    Braeger, M; Lang, A; Suwalska, A

    2011-01-01

    In complex operational environments, monitoring and control systems are asked to satisfy ever more stringent requirements. In addition to reliability, the availability of the system has become crucial to accommodate for tight planning schedules and increased dependencies to other systems. In this context, adapting a monitoring system to changes in its environment and meeting requests for new functionalities are increasingly challenging. Combining maintainability and high-availability within a portable architecture is the focus of this work. To meet these increased requirements, we present a new modular system developed at CERN. Using the experience gained from previous implementations, the new platform uses a multiserver architecture to allow running patches and updates to the application without affecting its availability. The data acquisition can also be reconfigured without any downtime or potential data loss. The modular architecture builds on a core system that aims to be reusable for mu...

  15. Challenges and Characteristics of Intelligent Autonomy for Internet of Battle Things in Highly Adversarial Environments

    OpenAIRE

    Kott, Alexander

    2018-01-01

    Numerous, artificially intelligent, networked things will populate the battlefield of the future, operating in close collaboration with human warfighters, and fighting as teams in highly adversarial environments. This paper explores the characteristics, capabilities and intelligence required of such a network of intelligent things and humans - Internet of Battle Things (IOBT). It will experience unique challenges that are not yet well addressed by the current generation of AI and machine lear...

  16. Scientific Grand Challenges: Forefront Questions in Nuclear Science and the Role of High Performance Computing

    International Nuclear Information System (INIS)

    Khaleel, Mohammad A.

    2009-01-01

    This report is an account of the deliberations and conclusions of the workshop on 'Forefront Questions in Nuclear Science and the Role of High Performance Computing' held January 26-28, 2009, co-sponsored by the U.S. Department of Energy (DOE) Office of Nuclear Physics (ONP) and the DOE Office of Advanced Scientific Computing (ASCR). Representatives from the national and international nuclear physics communities, as well as from the high performance computing community, participated. The purpose of this workshop was to (1) identify forefront scientific challenges in nuclear physics and then determine which-if any-of these could be aided by high performance computing at the extreme scale; (2) establish how and why new high performance computing capabilities could address issues at the frontiers of nuclear science; (3) provide nuclear physicists the opportunity to influence the development of high performance computing; and (4) provide the nuclear physics community with plans for development of future high performance computing capability by DOE ASCR.

  17. Scientific Grand Challenges: Forefront Questions in Nuclear Science and the Role of High Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Khaleel, Mohammad A.

    2009-10-01

    This report is an account of the deliberations and conclusions of the workshop on "Forefront Questions in Nuclear Science and the Role of High Performance Computing" held January 26-28, 2009, co-sponsored by the U.S. Department of Energy (DOE) Office of Nuclear Physics (ONP) and the DOE Office of Advanced Scientific Computing (ASCR). Representatives from the national and international nuclear physics communities, as well as from the high performance computing community, participated. The purpose of this workshop was to 1) identify forefront scientific challenges in nuclear physics and then determine which-if any-of these could be aided by high performance computing at the extreme scale; 2) establish how and why new high performance computing capabilities could address issues at the frontiers of nuclear science; 3) provide nuclear physicists the opportunity to influence the development of high performance computing; and 4) provide the nuclear physics community with plans for development of future high performance computing capability by DOE ASCR.

  18. Control techniques of tilt rotor unmanned aerial vehicle systems: A review

    Directory of Open Access Journals (Sweden)

    Zhong Liu

    2017-02-01

    Full Text Available The tilt rotor unmanned aerial vehicle (TRUAV exhibits special application value due to its unique rotor structure. However, varying dynamics and aerodynamic interference caused by tiltable rotors are great technical challenges and key issues for TRUAV’s high-powered flight controls, which have attracted the attention of many researchers. This paper outlines the concept of TRUAV and some typical TRUAV platforms while focusing on control techniques. TRUAV structural features, dynamics modeling, and flight control methods are discussed, and major challenges and corresponding developmental tendencies associated with TRUAV flight control are summarized.

  19. Current status and bioanalytical challenges in the detection of unknown anabolic androgenic steroids in doping control analysis.

    Science.gov (United States)

    Pozo, Oscar J; De Brabanter, Nik; Fabregat, Andreu; Segura, Jordi; Ventura, Rosa; Van Eenoo, Peter; Deventer, Koen

    2013-11-01

    Androgenic anabolic steroids (AAS) are prohibited in sports due to their anabolic effects. Doping control laboratories usually face the screening of AAS misuse by target methods based on MS detection. Although these methods allow for the sensitive and specific detection of targeted compounds and metabolites, the rest remain undetectable. This fact opens a door for cheaters, since different AAS can be synthesized in order to evade doping control tests. This situation was evidenced in 2003 with the discovery of the designer steroid tetrahydrogestrinone. One decade after this discovery, the detection of unknown AAS still remains one of the main analytical challenges in the doping control field. In this manuscript, the current situation in the detection of unknown AAS is reviewed. Although important steps have been made in order to minimize this analytical problem and different analytical strategies have been proposed, there are still some drawbacks related to each approach.

  20. Advantages and Challenges to the Use of On-Line Feedback in CERN’s Accelerators Controls Configuration Management

    CERN Document Server

    Zaharieva, Z; Rolland Lopez De Coca, J; Romero Marin, A

    2014-01-01

    The Controls Configuration Service (CCS) provides the Configuration Management facilities for the Controls System for all CERN accelerators. It complies with Configuration Management standards, tracking the life of configuration items and their relationships by allowing identification and triggering change management processes. Data stored in the CCS is extracted and propagated to the controls hardware for remote configuration. The article will present the ability of the CCS to audit items and verify conformance to specification with the implementation of on-line feedback focusing on Front-End Computers (FEC) configurations. Long-standing problems existed in this area such as discrepancies between the actual state of the FEC and the configuration sent to it at reboot. This resulted in difficult-to-diagnose behaviour and disturbance for the Operations team. The article will discuss the solution architecture (tailored processes and tools), the development and implementation challenges, as well as the advantages...

  1. Multi-resolution Delta-plus-SPH with tensile instability control: Towards high Reynolds number flows

    Science.gov (United States)

    Sun, P. N.; Colagrossi, A.; Marrone, S.; Antuono, M.; Zhang, A. M.

    2018-03-01

    It is well known that the use of SPH models in simulating flow at high Reynolds numbers is limited because of the tensile instability inception in the fluid region characterized by high vorticity and negative pressure. In order to overcome this issue, the δ+-SPH scheme is modified by implementing a Tensile Instability Control (TIC). The latter consists of switching the momentum equation to a non-conservative formulation in the unstable flow regions. The loss of conservation properties is shown to induce small errors, provided that the particle distribution is regular. The latter condition can be ensured thanks to the implementation of a Particle Shifting Technique (PST). The novel variant of the δ+-SPH is proved to be effective in preventing the onset of tensile instability. Several challenging benchmark tests involving flows past bodies at large Reynolds numbers have been used. Within this a simulation characterized by a deforming foil that resembles a fish-like swimming body is used as a practical application of the δ+-SPH model in biological fluid mechanics.

  2. The development of control systems for high power steam turbines

    International Nuclear Information System (INIS)

    Mathey, M.

    1983-01-01

    The functional and technological aspects of developments in the field of control systems for steam turbines over the last twenty years are analyzed. These developments have now culminated in very sophisticated systems which closely link electronics to high pressure hydraulic technology. A detailed description of these systeme high-lighting the high technical level of the control methods and the flexibility and reliability in service of turbines controlled in this way is given [fr

  3. The Evolution of Chemical High-Throughput Experimentation To Address Challenging Problems in Pharmaceutical Synthesis.

    Science.gov (United States)

    Krska, Shane W; DiRocco, Daniel A; Dreher, Spencer D; Shevlin, Michael

    2017-12-19

    The structural complexity of pharmaceuticals presents a significant challenge to modern catalysis. Many published methods that work well on simple substrates often fail when attempts are made to apply them to complex drug intermediates. The use of high-throughput experimentation (HTE) techniques offers a means to overcome this fundamental challenge by facilitating the rational exploration of large arrays of catalysts and reaction conditions in a time- and material-efficient manner. Initial forays into the use of HTE in our laboratories for solving chemistry problems centered around screening of chiral precious-metal catalysts for homogeneous asymmetric hydrogenation. The success of these early efforts in developing efficient catalytic steps for late-stage development programs motivated the desire to increase the scope of this approach to encompass other high-value catalytic chemistries. Doing so, however, required significant advances in reactor and workflow design and automation to enable the effective assembly and agitation of arrays of heterogeneous reaction mixtures and retention of volatile solvents under a wide range of temperatures. Associated innovations in high-throughput analytical chemistry techniques greatly increased the efficiency and reliability of these methods. These evolved HTE techniques have been utilized extensively to develop highly innovative catalysis solutions to the most challenging problems in large-scale pharmaceutical synthesis. Starting with Pd- and Cu-catalyzed cross-coupling chemistry, subsequent efforts expanded to other valuable modern synthetic transformations such as chiral phase-transfer catalysis, photoredox catalysis, and C-H functionalization. As our experience and confidence in HTE techniques matured, we envisioned their application beyond problems in process chemistry to address the needs of medicinal chemists. Here the problem of reaction generality is felt most acutely, and HTE approaches should prove broadly enabling

  4. Laboratory-controlled Challenges of Nile Tilapia (Oreochromis niloticus) with Streptococcus agalactiae: Comparisons between Immersion, Oral, Intracoelomic and Intramuscular Routes of Infection.

    Science.gov (United States)

    Soto, E; Zayas, M; Tobar, J; Illanes, O; Yount, S; Francis, S; Dennis, M M

    2016-11-01

    Streptococcus agalactiae, the aetiological agent of streptococcosis in fish, is an important pathogen of cultured and wild fish worldwide. To gain a better understanding of the pathogenesis of streptococcosis in Nile tilapia (Oreochromis niloticus), and to identify the experimental route of infection that most closely mimics natural disease, fingerlings were challenged with S. agalactiae utilizing different delivery methods. Fingerlings were challenged via intracoelomic injection (ICinj), intramuscular injection (IMinj), orally or by immersion with serial dilutions of S. agalactiae. The dose lethal to 50% of test fish 15 days post challenge was 120 colony forming units (CFU)/fish after ICinj, and 10 5  CFU/fish after IMinj. Acute mortalities were present in both groups, but were higher in the fish challenged by ICinj. Very low mortalities were observed in the fish challenged via oral or immersion routes. Post-mortem evaluation of survivors revealed classical lesions associated with fish streptococcosis, including granulomatous or lymphohistiocytic epicarditis, splenitis, meningitis, myocarditis, choroiditis and exophthalmia. The information obtained improves our understanding of the pathogenesis of streptococcosis in fish, and provides useful information regarding controlled experimental infections in tilapia challenged with S. agalactiae. Results from this study suggest that IMinj challenge methods are not only suitable to induce streptococcosis in tilapia, but they may be the preferred method to study the pathogenesis of the naturally-occurring disease in this species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Very-high-level neutral-beam control system

    International Nuclear Information System (INIS)

    Elischer, V.; Jacobson, V.; Theil, E.

    1981-10-01

    As increasing numbers of neutral beams are added to fusion machines, their operation can consume a significant fraction of a facility's total resources. LBL has developed a very high level control system that allows a neutral beam injector to be treated as a black box with just 2 controls: one to set the beam power and one to set the pulse duration. This 2 knob view allows simple operation and provides a natural base for implementing even higher level controls such as automatic source conditioning

  6. The ILC control system

    International Nuclear Information System (INIS)

    Carwardine, J.; Saunders, C.; Arnold, N.; Lenkszus, F.; Rehlich, K.; Simrock, S.; Banerjee, b.; Chase, B.; Gottschalk, E.; Joireman, P.; Kasley, P.; Lackey, S.; McBride, P.; Pavlicek, V.; Patrick, J.; Votava, M.; Wolbers, S.; Furukawa, K.; Michizono, S.; Larson, R.S.; Downing, R.

    2007-01-01

    Since the last ICALEPCS, a small multi-region team has developed a reference design model for a control system for the International Linear Collider as part of the ILC Global Design Effort. The scale and performance parameters of the ILC accelerator require new thinking in regards to control system design. Technical challenges include the large number of accelerator systems to be controlled, the large scale of the accelerator facility, the high degree of automation needed during accelerator operations, and control system equipment requiring 'Five Nines' availability. The R and D path for high availability touches the control system hardware, software, and overall architecture, and extends beyond traditional interfaces into the technical systems. Software considerations for HA include fault detection through exhaustive out-of-band monitoring and automatic state migration to redundant systems, while the telecom industry's emerging ATCA standard - conceived, specified, and designed for High Availability - is being evaluated for suitability for ILC front-end electronics.

  7. A wide range and high speed automatic gain control

    International Nuclear Information System (INIS)

    Tacconi, E.; Christiansen, C.

    1993-05-01

    Automatic gain control (AGC) techniques have been largely used since the beginning of electronics, but in most of the applications the dynamic response is slow compared with the carrier frequency. The problem of developing an automatic gain control with high dynamic response and wide control range simultaneously is analyzed in this work. An ideal gain control law, with the property that the total loop gain remains constant independent of the carrier amplitude, is obtained. The resulting AGC behavior is compared by computer simulations with a linear multiplier AGC. The ideal gain control law can be approximated using a transconductance amplifier. A practical circuit that has been used at CERN in the radio frequency loops of the Booster Synchrotron is presented. The circuit has high speed and 80-dB gain control range

  8. High temperature electrical energy storage: advances, challenges, and frontiers.

    Science.gov (United States)

    Lin, Xinrong; Salari, Maryam; Arava, Leela Mohana Reddy; Ajayan, Pulickel M; Grinstaff, Mark W

    2016-10-24

    With the ongoing global effort to reduce greenhouse gas emission and dependence on oil, electrical energy storage (EES) devices such as Li-ion batteries and supercapacitors have become ubiquitous. Today, EES devices are entering the broader energy use arena and playing key roles in energy storage, transfer, and delivery within, for example, electric vehicles, large-scale grid storage, and sensors located in harsh environmental conditions, where performance at temperatures greater than 25 °C are required. The safety and high temperature durability are as critical or more so than other essential characteristics (e.g., capacity, energy and power density) for safe power output and long lifespan. Consequently, significant efforts are underway to design, fabricate, and evaluate EES devices along with characterization of device performance limitations such as thermal runaway and aging. Energy storage under extreme conditions is limited by the material properties of electrolytes, electrodes, and their synergetic interactions, and thus significant opportunities exist for chemical advancements and technological improvements. In this review, we present a comprehensive analysis of different applications associated with high temperature use (40-200 °C), recent advances in the development of reformulated or novel materials (including ionic liquids, solid polymer electrolytes, ceramics, and Si, LiFePO 4 , and LiMn 2 O 4 electrodes) with high thermal stability, and their demonstrative use in EES devices. Finally, we present a critical overview of the limitations of current high temperature systems and evaluate the future outlook of high temperature batteries with well-controlled safety, high energy/power density, and operation over a wide temperature range.

  9. Challenges of controlling sleeping sickness in areas of violent conflict: experience in the Democratic Republic of Congo.

    Science.gov (United States)

    Tong, Jacqueline; Valverde, Olaf; Mahoudeau, Claude; Yun, Oliver; Chappuis, François

    2011-05-26

    Human African trypanosomiasis (HAT), or sleeping sickness, is a fatal neglected tropical disease if left untreated. HAT primarily affects people living in rural sub-Saharan Africa, often in regions afflicted by violent conflict. Screening and treatment of HAT is complex and resource-intensive, and especially difficult in insecure, resource-constrained settings. The country with the highest endemicity of HAT is the Democratic Republic of Congo (DRC), which has a number of foci of high disease prevalence. We present here the challenges of carrying out HAT control programmes in general and in a conflict-affected region of DRC. We discuss the difficulties of measuring disease burden, medical care complexities, waning international support, and research and development barriers for HAT. In 2007, Médecins Sans Frontières (MSF) began screening for HAT in the Haut-Uélé and Bas-Uélé districts of Orientale Province in northeastern DRC, an area of high prevalence affected by armed conflict. Through early 2009, HAT prevalence rate of 3.4% was found, reaching 10% in some villages. More than 46,000 patients were screened and 1,570 treated for HAT during this time. In March 2009, two treatment centres were forced to close due to insecurity, disrupting patient treatment, follow-up, and transmission-control efforts. One project was reopened in December 2009 when the security situation improved, and another in late 2010 based on concerns that population displacement might reactivate historic foci. In all of 2010, 770 patients were treated at these sites, despite a limited geographical range of action for the mobile teams. In conflict settings where HAT is prevalent, targeted medical interventions are needed to provide care to the patients caught in these areas. Strategies of integrating care into existing health systems may be unfeasible since such infrastructure is often absent in resource-poor contexts. HAT care in conflict areas must balance logistical and medical capacity

  10. Challenges of controlling sleeping sickness in areas of violent conflict: experience in the Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Yun Oliver

    2011-05-01

    Full Text Available Abstract Background Human African trypanosomiasis (HAT, or sleeping sickness, is a fatal neglected tropical disease if left untreated. HAT primarily affects people living in rural sub-Saharan Africa, often in regions afflicted by violent conflict. Screening and treatment of HAT is complex and resource-intensive, and especially difficult in insecure, resource-constrained settings. The country with the highest endemicity of HAT is the Democratic Republic of Congo (DRC, which has a number of foci of high disease prevalence. We present here the challenges of carrying out HAT control programmes in general and in a conflict-affected region of DRC. We discuss the difficulties of measuring disease burden, medical care complexities, waning international support, and research and development barriers for HAT. Discussion In 2007, Médecins Sans Frontières (MSF began screening for HAT in the Haut-Uélé and Bas-Uélé districts of Orientale Province in northeastern DRC, an area of high prevalence affected by armed conflict. Through early 2009, HAT prevalence rate of 3.4% was found, reaching 10% in some villages. More than 46,000 patients were screened and 1,570 treated for HAT during this time. In March 2009, two treatment centres were forced to close due to insecurity, disrupting patient treatment, follow-up, and transmission-control efforts. One project was reopened in December 2009 when the security situation improved, and another in late 2010 based on concerns that population displacement might reactivate historic foci. In all of 2010, 770 patients were treated at these sites, despite a limited geographical range of action for the mobile teams. Summary In conflict settings where HAT is prevalent, targeted medical interventions are needed to provide care to the patients caught in these areas. Strategies of integrating care into existing health systems may be unfeasible since such infrastructure is often absent in resource-poor contexts. HAT care in

  11. Challenges in fingertip replantation.

    Science.gov (United States)

    Kim, Jin-Soo; Yang, Jae-Won; Lee, Dong-Chul; Ki, Sae-Hwi; Roh, Si-Young

    2013-11-01

    Fingertip amputation is a challenging injury to manage. Among various reconstructive procedures, replantation results in superior outcome, but is seldom considered in many institutions. From the identification of vessel ends to reanastomosis of the submillimeter vessels, fingertip's highly specialized anatomy requires technical excellence. By addressing these anatomic challenges, fingertip replantation can be a routine reconstructive option for microvascular surgeons.

  12. Challenges in Fingertip Replantation

    OpenAIRE

    Kim, Jin-Soo; Yang, Jae-Won; Lee, Dong-Chul; Ki, Sae-Hwi; Roh, Si-Young

    2013-01-01

    Fingertip amputation is a challenging injury to manage. Among various reconstructive procedures, replantation results in superior outcome, but is seldom considered in many institutions. From the identification of vessel ends to reanastomosis of the submillimeter vessels, fingertip's highly specialized anatomy requires technical excellence. By addressing these anatomic challenges, fingertip replantation can be a routine reconstructive option for microvascular surgeons.

  13. Integrated High-Speed Torque Control System for a Robotic Joint

    Science.gov (United States)

    Davis, Donald R. (Inventor); Radford, Nicolaus A. (Inventor); Permenter, Frank Noble (Inventor); Valvo, Michael C. (Inventor); Askew, R. Scott (Inventor)

    2013-01-01

    A control system for achieving high-speed torque for a joint of a robot includes a printed circuit board assembly (PCBA) having a collocated joint processor and high-speed communication bus. The PCBA may also include a power inverter module (PIM) and local sensor conditioning electronics (SCE) for processing sensor data from one or more motor position sensors. Torque control of a motor of the joint is provided via the PCBA as a high-speed torque loop. Each joint processor may be embedded within or collocated with the robotic joint being controlled. Collocation of the joint processor, PIM, and high-speed bus may increase noise immunity of the control system, and the localized processing of sensor data from the joint motor at the joint level may minimize bus cabling to and from each control node. The joint processor may include a field programmable gate array (FPGA).

  14. [Challenge and strategy of prevention and control of important parasitic diseases under the Belt and Road Initiative].

    Science.gov (United States)

    Chun-Li, Cao; Jia-Gang, Guo

    2018-04-17

    China was once a country with the heaviest burden of parasitic diseases. Under the leadership of the Communist Party and national authority, after more than 60 years' efforts of prevention and control, the remarkable results have been achieved in China. However, affected by the social and economic development and environmental changes, the prevention and control of parasitic diseases, especially imported parasitic diseases, are facing new challenges, and the parasitic diseases, such as malaria, schistosomiasis, leishmaniasis, filariasis and trypanosomiasis, appear increasingly. With the development of the Belt and Road Initiative, the transmission risks of these diseases are more increased. The purpose of this paper is to describe the experience and results of parasitic disease prevention and control in China, understand the present parasitic disease epidemic situation of the Belt and Road Initiative related countries, analyze the transmission risks of important parasitic diseases, and present some relevant suggestions, so as to provide the evidence for the health administrative department formulating the prevention and control strategies of such parasitic diseases timely and effectively.

  15. Mosquito and Fly Surveillance and Control Research at the USDA-ARS Center for Medical, Agricultural and Veterinary Entomology: Solving Operational Challenges

    Science.gov (United States)

    The Mosquito and Fly Research Unit of the USDA-ARS Center for Medical, Agricultural and Veterinary Entomology located in Gainesville Florida is the largest Federal laboratory devoted to specifically solving operational mosquito and fly surveillance and control challenges in the U.S. and internationa...

  16. Benefits and Challenges of Technology in High Schools: A Voice from Educational Leaders with a Freire Echo

    Science.gov (United States)

    Preston, Jane P.; Wiebe, Sean; Gabriel, Martha; McAuley, Alexander; Campbell, Barbara; MacDonald, Ron

    2015-01-01

    The purpose of this study is to document the perceptions of school leaders pertaining to the benefits and challenges of technology in high schools located on Prince Edward Island (PEI) (Canada). For this qualitative study, we interviewed 11 educational leaders representing the PEI Department of Education, principals, vice-principals, and…

  17. Exploring Temporal Sequences of Regulatory Phases and Associated Interactions in Low- and High-Challenge Collaborative Learning Sessions

    Science.gov (United States)

    Sobocinski, Márta; Malmberg, Jonna; Järvelä, Sanna

    2017-01-01

    Investigating the temporal order of regulatory processes can explain in more detail the mechanisms behind success or lack of success during collaborative learning. The aim of this study is to explore the differences between high- and low-challenge collaborative learning sessions. This is achieved through examining how the three phases of…

  18. The implementation of the serial trial intervention for pain and challenging behaviour in advanced dementia patients (STA OP!): a clustered randomized controlled trial.

    NARCIS (Netherlands)

    Pieper, M.J.C.; Achterberg, W.P.; Francke, A.L.; Steen, J.T. van der; Scherder, E.J.A.; Kovach, C.R.

    2011-01-01

    BACKGROUND: Pain (physical discomfort) and challenging behaviour are highly prevalent in nursing home residents with dementia: at any given time 45-80% of nursing home residents are in pain and up to 80% have challenging behaviour. In the USA Christine Kovach developed the serial trial intervention

  19. The discovery and development of HIV therapy: the new challenges

    Directory of Open Access Journals (Sweden)

    Carlo Federico Perno

    2011-01-01

    Full Text Available The therapy of HIV infection has been dramatically improved over the years, and allowed the achievement of unexpected results. The availability of many drugs, and the knowledge of HIV related pathogenesis, helped in selecting highly effective antiviral therapies, yet today a major challenge stands, that is the selection of the best regimen(s in clinical practice. In this frame, evidence-based medicine remains a cornerstone of modern medicine, but its structure needs to be adapted to the new challenges, made by an excess of information (not always fully reliable, by highly sophisticated statistical systems that may overlook the clinical practice despite their ability to define the statistical significance, and the limited number of independent controlled studies. The revision of the criteria of evidence-based medicine, and their adaptation to the new tools available, may allow a better contribution to the definition of the best therapy for each single patient.

  20. Challenges to Providing a Successful Central Configuration Service to Support CERN’s New Controls Diagnostics and Monitoring System

    CERN Document Server

    Makonnen, Z; Zaharieva, Z

    2014-01-01

    The Controls Diagnostic and Monitoring service (DIAMON) provides monitoring and diagnostics tools to the operators in the CERN Control Centre. A recent reengineering presented the opportunity to restructure its data management and to integrate it with the central Controls Configuration Service (CCS). The CCS provides the Configuration Management for the Controls System for all accelerators at CERN. The new facility had to cater for the configuration management of all agents monitored by DIAMON, (>3000 computers of different types), provide deployment information, relations between metrics, and historical information. In addition, it had to be integrated into the operational CCS, while ensuring stability and data coherency. An important design decision was to largely reuse the existing infrastructure in the CCS and adapt the DIAMON data management to it e.g. by using the device/property model through a Virtual Devices framework to model the DIAMON agents. This article will show how these challenging requiremen...

  1. Teaching fluid mechanics to high schoolers: methods, challenges, and outcome

    Science.gov (United States)

    Manikantan, Harishankar

    2017-11-01

    This talk will summarize the goals, methods, and both short- and long-term feedback from two high-school-level courses in fluid mechanics involving 43 students and cumulatively spanning over 100 hours of instruction. The goals of these courses were twofold: (a) to spark an interest in science and engineering and attract a more diverse demographic into college-level STEM programs; and (b) to train students in a `college-like' method of approaching the physics of common phenomena, with fluid mechanics as the context. The methods of instruction included classes revolving around the idea of dispelling misconceptions, group activities, `challenge' rounds and mock design projects to use fluid mechanics phenomena to achieve a specified goal, and simple hands-on experiments. The feedback during instruction was overwhelmingly positive, particularly in terms of a changing and favorable attitude towards math and engineering. Long after the program, a visible impact lies in a diverse group of students acknowledging that the course had a positive effect in their decision to choose an engineering or science major in a four-year college.

  2. Control of high frequency microactuators using active structures

    International Nuclear Information System (INIS)

    Kreth, P A; Alvi, F S; Reese, B M; Oates, W S

    2015-01-01

    A fluidically driven microactuator that generates supersonic, pulsed microjets has been implemented with smart materials to actively and precisely control the frequency of the microjets in a closed-loop manner. Since this actuator relies on a number of microscale flow and acoustic phenomena to produce the pulsed microjets, its resonant frequency is determined by its geometry and other flow parameters. The design discussed in this paper integrates piezoelectric stacks by connecting them to movable sidewalls within the actuator such that the microactuator's internal geometry can be controlled by varying the voltage across the piezo-stacks. An open-loop control scheme demonstrates the frequency modulation capabilities that are enabled with this design: very large frequency deviations (up to ±500 Hz) around the actuator design frequency are attained at very high rates (up to 1 kHz). Closed-loop control of the microactuator's frequency was also demonstrated, and the results indicate that (combined with appropriate sensors) this actuator could be used effectively for active, feedback control in high-speed, resonance-dominated flowfields. This proof of concept study clearly illustrates the ability of this robust and compact actuator to produce perturbations that can be modulated and controlled based on the desired control objective. (paper)

  3. A high performance architecture for accelerator controls

    International Nuclear Information System (INIS)

    Allen, M.; Hunt, S.M; Lue, H.; Saltmarsh, C.G.; Parker, C.R.C.B.

    1991-01-01

    The demands placed on the Superconducting Super Collider (SSC) control system due to large distances, high bandwidth and fast response time required for operation will require a fresh approach to the data communications architecture of the accelerator. The prototype design effort aims at providing deterministic communication across the accelerator complex with a response time of < 100 ms and total bandwidth of 2 Gbits/sec. It will offer a consistent interface for a large number of equipment types, from vacuum pumps to beam position monitors, providing appropriate communications performance for each equipment type. It will consist of highly parallel links to all equipment: those with computing resources, non-intelligent direct control interfaces, and data concentrators. This system will give each piece of equipment a dedicated link of fixed bandwidth to the control system. Application programs will have access to all accelerator devices which will be memory mapped into a global virtual addressing scheme. Links to devices in the same geographical area will be multiplexed using commercial Time Division Multiplexing equipment. Low-level access will use reflective memory techniques, eliminating processing overhead and complexity of traditional data communication protocols. The use of commercial standards and equipment will enable a high performance system to be built at low cost

  4. A high performance architecture for accelerator controls

    International Nuclear Information System (INIS)

    Allen, M.; Hunt, S.M.; Lue, H.; Saltmarsh, C.G.; Parker, C.R.C.B.

    1991-03-01

    The demands placed on the Superconducting Super Collider (SSC) control system due to large distances, high bandwidth and fast response time required for operation will require a fresh approach to the data communications architecture of the accelerator. The prototype design effort aims at providing deterministic communication across the accelerator complex with a response time of <100 ms and total bandwidth of 2 Gbits/sec. It will offer a consistent interface for a large number of equipment types, from vacuum pumps to beam position monitors, providing appropriate communications performance for each equipment type. It will consist of highly parallel links to all equipments: those with computing resources, non-intelligent direct control interfaces, and data concentrators. This system will give each piece of equipment a dedicated link of fixed bandwidth to the control system. Application programs will have access to all accelerator devices which will be memory mapped into a global virtual addressing scheme. Links to devices in the same geographical area will be multiplexed using commercial Time Division Multiplexing equipment. Low-level access will use reflective memory techniques, eliminating processing overhead and complexity of traditional data communication protocols. The use of commercial standards and equipment will enable a high performance system to be built at low cost. 1 fig

  5. Reprogrammable Controller Design From High-Level Specification

    Directory of Open Access Journals (Sweden)

    M. Benmohammed

    2003-10-01

    Full Text Available Existing techniques in high-level synthesis mostly assume a simple controller architecture model in the form of a single FSM. However, in reality more complex controller architectures are often used. On the other hand, in the case of programmable processors, the controller architecture is largely defined by the available control-flow instructions in the instruction set. With the wider acceptance of behavioral synthesis, the application of these methods for the design of programmable controllers is of fundamental importance in embedded system technology. This paper describes an important extension of an existing architectural synthesis system targeting the generation of ASIP reprogrammable architectures. The designer can then generate both style of architecture, hardwired and programmable, using the same synthesis system and can quickly evaluate the trade-offs of hardware decisions.

  6. Simple Motor Control Concept Results High Efficiency at High Velocities

    Science.gov (United States)

    Starin, Scott; Engel, Chris

    2013-09-01

    The need for high velocity motors in space applications for reaction wheels and detectors has stressed the limits of Brushless Permanent Magnet Motors (BPMM). Due to inherent hysteresis core losses, conventional BPMMs try to balance the need for torque verses hysteresis losses. Cong-less motors have significantly less hysteresis losses but suffer from lower efficiencies. Additionally, the inherent low inductance in cog-less motors result in high ripple currents or high switching frequencies, which lowers overall efficiency and increases performance demands on the control electronics.However, using a somewhat forgotten but fully qualified technology of Isotropic Magnet Motors (IMM), extremely high velocities may be achieved at low power input using conventional drive electronics. This paper will discuss the trade study efforts and empirical test data on a 34,000 RPM IMM.

  7. The diesel challenge

    International Nuclear Information System (INIS)

    Tobin, Geoff

    1997-01-01

    This article is focused on the challenges being faced by the diesel producer and these include a number of interesting developments which illustrate the highly competitive world of the European refiner. These include: The tightening quality requirements being legislated coupled with the availability of the ''city diesel'' from Scandinavia and elsewhere which is already being sold into the market. For a time there will be a clear means of product differentiation. One of the key questions is whether the consumer will value the quality difference; a growing demand for diesel which is outstripping the growth in gasoline demand and causing refiners headaches when it comes to balancing their supply/demand barrels; the emergence of alternative fuels which are challenging the traditional markets of the refiner and in particular, the niche markets for the higher quality diesel fuels. All of this at a time of poor margins and over-capacity in the industry with further major challenges ahead such as fuel oil disposal, tighter environmental standards and the likelihood of heavier, higher sulphur crude oils in the future. Clearly, in such a difficult and highly-competitive business environment it will be important to find low-cost solutions to the challenges of the diesel quality changes. An innovative approach will be required to identify the cheapest and best route to enable the manufacture of the new quality diesel. (Author)

  8. Multiple Property Cross Direction Control of Paper Machines

    Directory of Open Access Journals (Sweden)

    Markku Ohenoja

    2011-07-01

    Full Text Available Cross direction (CD control in sheet-forming process forms a challenging problem with high dimensions. Accounting the interactions between different properties and actuators, the dimensionality increases further and also computational issues arise. We present a multiple property controller feasible to be used especially with imaging measurements that provide high sampling frequency and therefore enable short control interval. The simulation results state the benefits of multiple property CD control over single property control and single property control using full feedforward compensation. The controller presented may also be tuned in automated manner and the results demonstrate the effect of tuning on input saturation.

  9. Embedded control system for high power RF amplifiers

    International Nuclear Information System (INIS)

    Sharma, Deepak Kumar; Gupta, Alok Kumar; Jain, Akhilesh; Hannurkar, P.R.

    2011-01-01

    RF power devices are usually very sensitive to overheat and reflected RF power; hence a protective interlock system is required to be embedded with high power solid state RF amplifiers. The solid state RF amplifiers have salient features of graceful degradation and very low mean time to repair (MTTR). In order to exploit these features in favour of lowest system downtime, a real-time control system is embedded with high power RF amplifiers. The control system is developed with the features of monitoring, measurement and network publishing of various parameters, historical data logging, alarm generation, displaying data to the operator and tripping the system in case of any interlock failure. This paper discusses the design philosophy, features, functions and implementation details of the embedded control system. (author)

  10. anaesthetic challenges in a high risk parturient with myasthenia

    African Journals Online (AJOL)

    2013-10-10

    Oct 10, 2013 ... Intraoperative myasthenia crisis was managed with neostigmine infusion. She was managed in ... but world-wide, it is twice as common in women as in men and frequently .... could be a challenge when they present for surgery. The ideal anaesthetic ... intravenous opioids, neuromuscular blocking drugs,.

  11. [High-grade pressure sores in frail older high-risk persons. A retrospective postmortem case-control-study].

    Science.gov (United States)

    Von Renteln-Kruse, W; Krause, T; Anders, J; Kühl, M; Heinemann, A; Püschel, K

    2004-04-01

    Some old persons at risk do develop, but others, at comparable risk, do not develop high-grade pressure sores. To evaluate potentially different risk factors, we performed a post mortem case-control study in old persons who developed high-grade pressure sores within six months until 14 days before death. Consecutive cases with pressure sores grade >/=3 and potential controls at comparably high risk for pressure sores were examined before cremation. After written informed consent had been obtained by the next relatives, all available nursing and medical records of the deceased were thoroughly evaluated. Cases and controls were matched according to age, gender, immobility, and cachexia.A total of 100 cases with 71 pressure sores grade 3 and 29 pressure sores grade 4 were compared to 100 controls with 27 pressure sores grade pressure sores in frail older high-risk persons. Sedative drug effects and impaired patient compliance with preventive and therapeutic measures may also be associated with the development of high-grade pressure sores in old persons at high risk.

  12. Oligomeric recombinant H5 HA1 vaccine produced in bacteria protects ferrets from homologous and heterologous wild-type H5N1 influenza challenge and controls viral loads better than subunit H5N1 vaccine by eliciting high-affinity antibodies.

    Science.gov (United States)

    Verma, Swati; Dimitrova, Milena; Munjal, Ashok; Fontana, Juan; Crevar, Corey J; Carter, Donald M; Ross, Ted M; Khurana, Surender; Golding, Hana

    2012-11-01

    Recombinant hemagglutinin from influenza viruses with pandemic potential can be produced rapidly in various cell substrates. In this study, we compared the functionality and immunogenicity of bacterially produced oligomeric or monomeric HA1 proteins from H5N1 (A/Vietnam/1203/04) with those of the egg-based licensed subunit H5N1 (SU-H5N1) vaccine in ferrets challenged with homologous or heterologous H5N1 highly pathogenic influenza strains. Ferrets were vaccinated twice with the oligomeric or monomeric rHA1 or with SU-H5N1 (Sanofi Pasteur) emulsified with Titermax adjuvant and were challenged with wild-type homologous (A/Vietnam/1203/04; clade 1) or heterologous (A/Whooperswan/Mongolia/244/2005; clade 2.2) virus. Only the oligomeric rHA1 (not the monomeric rHA1) immunogen and the SU-H5N1 vaccine provided protection against the lethality and morbidity of homologous and heterologous highly pathogenic H5N1. Oligomeric rHA1 generated more cross-neutralizing antibodies and higher levels of serum antibody binding to HA1, with stronger avidity and a better IgG/IgM ratio, than monomeric HA1 and SU-H5N1 vaccines, as determined by surface plasmon resonance (SPR). Importantly, viral loads after heterologous H5N1 challenge were more efficiently controlled in ferrets vaccinated with the oligomeric rHA1 immunogen than in SU-H5N1-vaccinated ferrets. The reduction of viral loads in the nasal washes correlated strongly with higher-avidity antibodies to oligomeric rHA1 derived from H5N1 clade 1 and clade 2.2 viruses, as measured by SPR. This is the first study to show the role of antibody avidity for the HA1 globular head domain in reduction of viral loads in the upper respiratory tract, which could significantly reduce viral transmission.

  13. Towards high performance processing in modern Java-based control systems

    International Nuclear Information System (INIS)

    Misiowiec, M.; Buczak, W.; Buttner, M.

    2012-01-01

    CERN controls software is often developed on Java foundation. Some systems carry out a combination of data, network and processor intensive tasks within strict time limits. Hence, there is a demand for high performing, quasi real time solutions. The system must handle dozens of thousands of data samples every second, along its three tiers, applying complex computations throughout. To accomplish the goal, a deep understanding of multi-threading, memory management and inter process communication was required. There are unexpected traps hidden behind an excessive use of 64 bit memory or severe impact on the processing flow of modern garbage collectors. Tuning JVM configuration significantly affects the execution of the code. Even more important is the amount of threads and the data structures used between them. Accurately dividing work into independent tasks might boost system performance. Thorough profiling with dedicated tools helped understand the bottlenecks and choose algorithmically optimal solutions. Different virtual machines were tested, in a variety of setups and garbage collection options. The overall work provided for discovering actual hard limits of the whole setup. We present this process of designing a challenging system in view of the characteristics and limitations of the contemporary Java run-time environment. (authors)

  14. High speed reaction wheels for satellite attitude control and energy storage

    Science.gov (United States)

    Studer, P.; Rodriguez, E.

    1985-01-01

    The combination of spacecraft attitude control and energy storage (ACES) functions in common hardware, to synergistically maintain three-axis attitude control while supplying electrical power during earth orbital eclipses, allows the generation of control torques by high rotating speed wheels that react against the spacecraft structure via a high efficiency bidirectional energy conversion motor/generator. An ACES system encompasses a minimum of four wheels, controlling power and the three torque vectors. Attention is given to the realization of such a system with composite flywheel rotors that yield high energy density, magnetic suspension technology yielding low losses at high rotational speeds, and an ironless armature permanent magnet motor/generator yielding high energy conversion efficiency.

  15. Improvement of Control Infrastructure and High Level Application for KOMAC LINAC

    Energy Technology Data Exchange (ETDEWEB)

    Song, Young-Gi; Kim, Jae-Ha; Ahn, Tae-Sung; Kwon, Hyeok-Jung; Cho, Yong-Sub [Korea Atomic Energy Research Institute, Gyeongju (Korea, Republic of)

    2015-10-15

    The Korea multi-purpose accelerator complex (KOMAC) has two beam extraction points at 20 and 100 MeV for proton beam utilization. There are about 70 control systems for controlling the KOMAC subsystems, such as the ion source, the radio frequency, the diagnostic devices, the magnet power supply, and the cooling system. The infrastructure which includes network system, local controllers, and control system environment was required to be changed to process increasing process variables without fail. Experimental Physics and Industrial Control System (EPICS) based high level control environment which includes alarm, data archiving was changed to support the improved infrastructure of KOMAC control system. In this paper, we will describe the improvement of infrastructures for the KOMAC control system and EPICS based high level application. We improved the control network environment and EPCIS based high level application for enhancement of the KOMAC control system.

  16. Protein Biomarkers for Early Detection of Pancreatic Ductal Adenocarcinoma: Progress and Challenges.

    Science.gov (United States)

    Root, Alex; Allen, Peter; Tempst, Paul; Yu, Kenneth

    2018-03-07

    Approximately 75% of patients with pancreatic ductal adenocarcinoma are diagnosed with advanced cancer, which cannot be safely resected. The most commonly used biomarker CA19-9 has inadequate sensitivity and specificity for early detection, which we define as Stage I/II cancers. Therefore, progress in next-generation biomarkers is greatly needed. Recent reports have validated a number of biomarkers, including combination assays of proteins and DNA mutations; however, the history of translating promising biomarkers to clinical utility suggests that several major hurdles require careful consideration by the medical community. The first set of challenges involves nominating and verifying biomarkers. Candidate biomarkers need to discriminate disease from benign controls with high sensitivity and specificity for an intended use, which we describe as a two-tiered strategy of identifying and screening high-risk patients. Community-wide efforts to share samples, data, and analysis methods have been beneficial and progress meeting this challenge has been achieved. The second set of challenges is assay optimization and validating biomarkers. After initial candidate validation, assays need to be refined into accurate, cost-effective, highly reproducible, and multiplexed targeted panels and then validated in large cohorts. To move the most promising candidates forward, ideally, biomarker panels, head-to-head comparisons, meta-analysis, and assessment in independent data sets might mitigate risk of failure. Much more investment is needed to overcome these challenges. The third challenge is achieving clinical translation. To moonshot an early detection test to the clinic requires a large clinical trial and organizational, regulatory, and entrepreneurial know-how. Additional factors, such as imaging technologies, will likely need to improve concomitant with molecular biomarker development. The magnitude of the clinical translational challenge is uncertain, but interdisciplinary

  17. Protein Biomarkers for Early Detection of Pancreatic Ductal Adenocarcinoma: Progress and Challenges

    Directory of Open Access Journals (Sweden)

    Alex Root

    2018-03-01

    Full Text Available Approximately 75% of patients with pancreatic ductal adenocarcinoma are diagnosed with advanced cancer, which cannot be safely resected. The most commonly used biomarker CA19-9 has inadequate sensitivity and specificity for early detection, which we define as Stage I/II cancers. Therefore, progress in next-generation biomarkers is greatly needed. Recent reports have validated a number of biomarkers, including combination assays of proteins and DNA mutations; however, the history of translating promising biomarkers to clinical utility suggests that several major hurdles require careful consideration by the medical community. The first set of challenges involves nominating and verifying biomarkers. Candidate biomarkers need to discriminate disease from benign controls with high sensitivity and specificity for an intended use, which we describe as a two-tiered strategy of identifying and screening high-risk patients. Community-wide efforts to share samples, data, and analysis methods have been beneficial and progress meeting this challenge has been achieved. The second set of challenges is assay optimization and validating biomarkers. After initial candidate validation, assays need to be refined into accurate, cost-effective, highly reproducible, and multiplexed targeted panels and then validated in large cohorts. To move the most promising candidates forward, ideally, biomarker panels, head-to-head comparisons, meta-analysis, and assessment in independent data sets might mitigate risk of failure. Much more investment is needed to overcome these challenges. The third challenge is achieving clinical translation. To moonshot an early detection test to the clinic requires a large clinical trial and organizational, regulatory, and entrepreneurial know-how. Additional factors, such as imaging technologies, will likely need to improve concomitant with molecular biomarker development. The magnitude of the clinical translational challenge is uncertain, but

  18. Implementing an Alcohol and Other Drug Use Prevention Program Using University-High School Partnerships: Challenges and Lessons Learned

    Science.gov (United States)

    Milroy, Jeffrey J.; Orsini, Muhsin Michael; Wyrick, David L.; Fearnow-Kenney, Melodie; Wagoner, Kimberly G.; Caldwell, Rebecca

    2015-01-01

    Background: School-based alcohol and other drug use prevention remains an important national strategy. Collaborative partnerships between universities and high schools have the potential to enhance prevention programming; however, there are challenges to sustaining such partnerships. Purpose: The purpose of this commentary is to underscore…

  19. Off The Beaten Lane: AI Challenges In MOBAs Beyond Player Control

    OpenAIRE

    Cook, Michael; Summerville, Adam; Colton, Simon

    2017-01-01

    MOBAs represent a huge segment of online gaming and are growing as both an eSport and a casual genre. The natural starting point for AI researchers interested in MOBAs is to develop an AI to play the game better than a human - but MOBAs have many more challenges besides adversarial AI. In this paper we introduce the reader to the wider context of MOBA culture, propose a range of challenges faced by the community today, and posit concrete AI projects that can be undertaken to begin solving them.

  20. System for high-voltage control detectors with large number photomultipliers

    International Nuclear Information System (INIS)

    Donskov, S.V.; Kachanov, V.A.; Mikhajlov, Yu.V.

    1985-01-01

    A simple and inexpensive on-line system for hihg-voltage control which is designed for detectors with a large number of photomultipliers is developed and manufactured. It has been developed for the GAMC type hodoscopic electromagnetic calorimeters, comprising up to 4 thousand photomultipliers. High voltage variation is performed by a high-speed potentiometer which is rotated by a microengine. Block-diagrams of computer control electronics are presented. The high-voltage control system has been used for five years in the IHEP and CERN accelerator experiments. The operation experience has shown that it is quite simple and convenient in operation. In case of about 6 thousand controlled channels in both experiments no potentiometer and microengines failures were observed

  1. Infection control practice in countries with limited resources

    Directory of Open Access Journals (Sweden)

    Alp Emine

    2011-10-01

    Full Text Available Abstract Nosocomial infections and their control are a world-wide challenge. The prevalence of nosocomial infections is generally higher in developing countries with limited resources than industrialized countries. In this paper we aimed to further explain the differences with regard to infection control challenges between Turkey, a country with "limited" resources, and the Netherlands, a country with "reasonable" resources. Infrastructure of hospitals, low compliance of hand hygiene, understaffing, overcrowding, heavy workload, misuse of personal protective equipments, late establishment of infection control programme are major problems in limited-resources countries. These problems cause high infection rates and spread of multi-drug resistant pathogens. To improve the control and prevention of infections in countries with limited resources, a multi-facet approach is needed.

  2. Computer-aided control of high-quality cast iron

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2008-04-01

    Full Text Available The study discusses the possibility of control of the high-quality grey cast iron and ductile iron using the author’s genuine computer programs. The programs have been developed with the help of algorithms based on statistical relationships that are said to exist between the characteristic parameters of DTA curves and properties, like Rp0,2, Rm, A5 and HB. It has been proved that the spheroidisation and inoculation treatment of cast iron changes in an important way the characteristic parameters of DTA curves, thus enabling a control of these operations as regards their correctness and effectiveness, along with the related changes in microstructure and mechanical properties of cast iron. Moreover, some examples of statistical relationships existing between the typical properties of ductile iron and its control process were given for cases of the melts consistent and inconsistent with the adopted technology.A test stand for control of the high-quality cast iron and respective melts has been schematically depicted.

  3. High-volume manufacturing device overlay process control

    Science.gov (United States)

    Lee, Honggoo; Han, Sangjun; Woo, Jaeson; Lee, DongYoung; Song, ChangRock; Heo, Hoyoung; Brinster, Irina; Choi, DongSub; Robinson, John C.

    2017-03-01

    Overlay control based on DI metrology of optical targets has been the primary basis for run-to-run process control for many years. In previous work we described a scenario where optical overlay metrology is performed on metrology targets on a high frequency basis including every lot (or most lots) at DI. SEM based FI metrology is performed ondevice in-die as-etched on an infrequent basis. Hybrid control schemes of this type have been in use for many process nodes. What is new is the relative size of the NZO as compared to the overlay spec, and the need to find more comprehensive solutions to characterize and control the size and variability of NZO at the 1x nm node: sampling, modeling, temporal frequency and control aspects, as well as trade-offs between SEM throughput and accuracy.

  4. HIGH RESOLUTION ANALOG / DIGITAL POWER SUPPLY CONTROLLER

    International Nuclear Information System (INIS)

    Medvedko, Evgeny A

    2003-01-01

    Corrector magnets for the SPEAR-3 synchrotron radiation source require precision, high-speed control for use with beam-based orbit feedback. A new Controller Analog/Digital Interface card (CANDI) has been developed for these purposes. The CANDI has a 24-bit DAC for current control and three 24-bit Δ-Σ ADCs to monitor current and voltages. The ADCs can be read and the DAC updated at the 4 kHz rate needed for feedback control. A precision 16-bit DAC provides on-board calibration. Programmable multiplexers control internal signal routing for calibration, testing, and measurement. Feedback can be closed internally on current setpoint, externally on supply current, or beam position. Prototype and production tests are reported in this paper. Noise is better than 17 effective bits in a 10 mHz to 2 kHz bandwidth. Linearity and temperature stability are excellent

  5. Advanced Issues of Wind Turbine Modelling and Control

    International Nuclear Information System (INIS)

    Simani, Silvio

    2015-01-01

    The motivation for this paper comes from a real need to have an overview about the challenges of modelling and control for very demanding systems, such as wind turbine systems, which require reliability, availability, maintainability, and safety over power conversion efficiency. These issues have begun to stimulate research and development in the wide control community particularly for these installations that need a high degree of “sustainability”. Note that this topic represents a key point mainly for offshore wind turbines with very large rotors, since they are characterised by challenging modelling and control problems, as well as expensive and safety critical maintenance works. In this case, a clear conflict exists between ensuring a high degree of availability and reducing maintenance times, which affect the final energy cost. On the other hand, wind turbines have highly nonlinear dynamics, with a stochastic and uncontrollable driving force as input in the form of wind speed, thus representing an interesting challenge also from the modelling point of view. Suitable control methods can provide a sustainable optimisation of the energy conversion efficiency over wider than normally expected working conditions. Moreover, a proper mathematical description of the wind turbine system should be able to capture the complete behaviour of the process under monitoring, thus providing an important impact on the control design itself. In this way, the control scheme could guarantee prescribed performance, whilst also giving a degree of “tolerance” to possible deviation of characteristic properties or system parameters from standard conditions, if properly included in the wind turbine model itself. The most important developments in advanced controllers for wind turbines are addressed, and open problems in the areas of modelling of wind turbines are also outlined. (paper)

  6. How Potassium Can Help Control High Blood Pressure

    Science.gov (United States)

    ... Aneurysm More How Potassium Can Help Control High Blood Pressure Updated:Jan 29,2018 Understanding the heart-healthy ... This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  7. Challenges in Unmanned Aerial Vehicle Photogrammetry for Archaeological Mapping at High Elevations

    Science.gov (United States)

    Adams, J. A.; Wernke, S.

    2015-12-01

    Unmanned Aerial Vehicles (UAVs), especially multi-rotor vehicles, are becoming ubiquitous and their appeal for generating photogrammetry-based maps has grown. The options are many and costs have plummeted in last five years; however, many challenges persist with their deployment. We mapped the archaeological site Maw­chu Llacta, a settlement in the southern highlands of Peru (Figure 1). Mawchu Llacta is a planned colonial town built over a major Inka-era center in the high-elevation grasslands at ~4,000m asl. The "general resettlement of Indians" was a massive forced resettlement program, for which very little local-level documentation exists. Mawachu Llacta's excellently preserved architecture includes >500 buildings and hundreds of walls spread across ~13h posed significant mapping challenges. Many environmental factors impact UAV deployment. The air pressure at 4,100 m asl is dramatically lower than at sea level. The dry season diurnal temperature differentials can vary from 7°C to 22°C daily. High and hot conditions frequently occur from late morning to early afternoon. Reaching Mawchu Llacta requires hiking 4km with 400m of vertical gain over steep and rocky terrain. There is also no on-site power or secure storage. Thus, the UAV must be packable. FAA regulations govern US UAV deployments, but regulations were less stringent in Peru. However, ITAR exemptions and Peruvian customs requirements were required. The Peruvian government has established an importation and approval process that entails leaving the UAV at customs, while obtaining the necessary government approvals, both of which can be problematic. We have deployed the Aurora Flight Sciences Skate fixed wing ßUAV, an in-house fixed wing UAV based on the Skywalker X-5 flying wing, and a tethered 9 m3 capacity latex meteorological weather balloon. Development of an autonomous blimp/balloon has been ruled-out. A 3DR Solo is being assessed for excavation mapping.

  8. Perceived parental affectionless control is associated with high neuroticism

    OpenAIRE

    Takahashi,Nana; Suzuki,Akihito; Matsumoto,Yoshihiko; Shirata,Toshinori; Otani,Koichi

    2017-01-01

    Nana Takahashi, Akihito Suzuki, Yoshihiko Matsumoto, Toshinori Shirata, Koichi Otani Department of Psychiatry, Yamagata University School of Medicine, Yamagata, Japan Objective: Depressed patients are prone to perceive that they were exposed to affectionless control by parents. Meanwhile, high neuroticism is a well-established risk factor for developing depression. Therefore, this study examined whether perceived parental affectionless control is associated with high neuroticism.Methods: Th...

  9. Nuclear weapons, scientists, and the post-Cold War challenge selected papers on arms control

    CERN Document Server

    Drell, Sidney D

    2007-01-01

    This volume includes a representative selection of Sidney Drell's recent writings and speeches (circa 1993 to the present) on public policy issues with substantial scientific components. Most of the writings deal with national security, nuclear weapons, and arms control and reflect the author's personal involvement in such issues dating back to 1960. Fifteen years after the demise of the Soviet Union, the gravest danger presented by nuclear weapons is the spread of advanced technology that may result in the proliferation of nuclear weapons. Of most concern would be their acquisition by hostile governments and terrorists who are unconstrained by accepted norms of civilized behavior. The current challenges are to prevent this from happening and, at the same time, to pursue aggressively the opportunity to escape from an outdated nuclear deterrence trap.

  10. Risks and challenges associated with the design and construction of a nuclear power plant; Control de riesgos y retos asociados al diseno y construccion de una central nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Liebana Martinez, B.; Armas Garcia, A.; Martinez Gozalo, I.

    2011-07-01

    The construction of a nuclear power plant project, considering the period prior to the operation of the plant, requires a very strict risk control to ensure compliance with a series of challenges. The present paper identifying the most important challenges facing the construct ability and license requirements of the process, identifying the interfaces and proposing a methodology of construction to meet the challenge of a construction process in 5 years.

  11. Development and characterization of high-frequency resonance-enhanced microjet actuators for control of high-speed jets

    Science.gov (United States)

    Upadhyay, Puja; Gustavsson, Jonas P. R.; Alvi, Farrukh S.

    2016-05-01

    For flow control applications requiring high-frequency excitation, very few actuators have sufficient dynamic response and/or control authority to be useful in high-speed flows. Due to this reason, experiments involving high-frequency excitation, attempted in the past, have been limited to either low-frequency actuation with reasonable control authority or moderate-frequency actuation with limited control authority. The current work expands on the previous development of the resonance-enhanced microactuators to design actuators that are capable of producing high-amplitude pulses at much higher frequencies [{O} (10 kHz)]. Using lumped element modeling, two actuators have been designed with nominal frequencies of 20 and 50 kHz. Extensive benchtop characterization using acoustic measurements as well as optical diagnostics using a high-resolution micro-schlieren setup is employed to characterize the dynamic response of these actuators. The actuators performed at a range of frequencies, 20.3-27.8 and 54.8-78.2 kHz, respectively. In addition to providing information on the actuator flow physics and performance at various operating conditions, this study serves to develop easy-to-integrate high-frequency actuators for active control of high-speed jets. Preliminary testing of these actuators is performed by implementing the 20-kHz actuator on a Mach 0.9 free jet flow field for noise reduction. Acoustic measurements in the jet near field demonstrate attenuation of radiated noise at all observation angles.

  12. High level model predictive control for plug-and-play process control with stability guaranty

    DEFF Research Database (Denmark)

    Michelsen, Axel Gottlieb; Stoustrup, Jakob

    2010-01-01

    In this paper a method for designing a stabilizing high level model predictive controller for a hierarchical plug- and-play process is presented. This is achieved by abstracting the lower layers of the controller structure as low order models with uncertainty and by using a robust model predictive...... controller for generating the references for these. A simulation example, in which the actuators in a process control system are changed, is reported to show the potential of this approach for plug and play process control....

  13. Challenges for utilization of the new synchrotron facilities

    International Nuclear Information System (INIS)

    Attwood, D.

    1989-08-01

    The emergence of third generation synchrotron radiation facilities provides new scientific opportunities and challenges. Optimized for small phase space electron beams, long periodic magnet structures, and dedicated scientific user access -- these new machines promise significant increases in spectral brightness, as well as enhanced spatial and temporal coherence properties, which translates to new opportunities for combining high spatial and spectral resolution. The challenges to the machine builders are well known: designing and maintaining the small phase space beams, constructing long magnet structures with minimal errors, stabilizing the beam to long and short term fluctuations, and multiple undulator tuning, to name a few. The challenges in beamline optics, spectroscopic and focusing systems are also quite clear. The issue of optical stability quickly comes to the forefront as we attempt to focus and image to ever finer spatial scales, with minimal loss of photon flux. Surface figure and polish are of greater importance, as is minimization of aberrations, as we strive to maintain these small phase space photon beams. The higher intensities and power loading mandate cooled, or cleverly controlled optics, to avoid thermal distortion. Spectroscopic efficiency, with minimal wavefront distortion to the near diffraction limited radiation, becomes more important, as do order and harmonic suppression resolution are called for -- with both diffractive and reflective optics. Two of our major issues will be efficient time sharing of these valuable resources, relegating time consuming setup procedures to branch lines while others take data, and controlling the cost of these ever more complex beamline engineering systems. 12 refs., 6 figs., 8 tabs

  14. Psychiatric comorbidities in asperger syndrome and high functioning autism: diagnostic challenges

    Directory of Open Access Journals (Sweden)

    Mazzone Luigi

    2012-06-01

    Full Text Available Abstract Several psychiatric conditions, both internalizing and externalizing, have been documented in comorbidity with Asperger Syndrome (AS and High Functioning Autism (HFA. In this review we examine the interplay between psychiatric comorbidities and AS/HFA. In particular, we will focus our attention on three main issues. First, we examine which psychiatric disorders are more frequently associated with AS/HFA. Second, we review which diagnostic tools are currently available for clinicians to investigate and diagnose the associated psychiatric disorders in individuals with AS/HFA. Third, we discuss the challenges that clinicians and researchers face in trying to determine whether the psychiatric symptoms are phenotypic manifestations of AS/HFA or rather they are the expression of a distinct, though comorbid, disorder. We will also consider the role played by the environment in the manifestation and interpretation of these symptoms. Finally, we will propose some strategies to try to address these issues, and we will discuss therapeutic implications.

  15. Psychiatric comorbidities in asperger syndrome and high functioning autism: diagnostic challenges

    Science.gov (United States)

    2012-01-01

    Several psychiatric conditions, both internalizing and externalizing, have been documented in comorbidity with Asperger Syndrome (AS) and High Functioning Autism (HFA). In this review we examine the interplay between psychiatric comorbidities and AS/HFA. In particular, we will focus our attention on three main issues. First, we examine which psychiatric disorders are more frequently associated with AS/HFA. Second, we review which diagnostic tools are currently available for clinicians to investigate and diagnose the associated psychiatric disorders in individuals with AS/HFA. Third, we discuss the challenges that clinicians and researchers face in trying to determine whether the psychiatric symptoms are phenotypic manifestations of AS/HFA or rather they are the expression of a distinct, though comorbid, disorder. We will also consider the role played by the environment in the manifestation and interpretation of these symptoms. Finally, we will propose some strategies to try to address these issues, and we will discuss therapeutic implications. PMID:22731684

  16. Notification: FY 2017 Update of Proposed Key Management Challenges and Internal Control Weaknesses Confronting the U.S. Chemical Safety and Hazard Investigation Board

    Science.gov (United States)

    Jan 5, 2017. The EPA OIG is beginning work to update for fiscal year 2017 its list of proposed key management challenges and internal control weaknesses confronting the U.S. Chemical Safety and Hazard Investigation Board (CSB).

  17. Formal verification of industrial control systems

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Verification of critical software is a high priority but a challenging task for industrial control systems. For many kinds of problems, testing is not an efficient method. Formal methods, such as model checking appears to be an appropriate complementary method. However, it is not common to use model checking in industry yet, as this method needs typically formal methods expertise and huge computing power. In the EN-ICE-PLC section, we are working on a [methodology][1] and a tool ([PLCverif][2]) to overcome these challenges and to integrate formal verification in the development process of our PLC-based control systems. [1]: http://cern.ch/project-plc-formalmethods [2]: http://cern.ch/plcverif

  18. Opportunity by Design: New High School Models for Student Success. Carnegie Challenge

    Science.gov (United States)

    Hamilton, Leah; Mackinnon, Anne

    2013-01-01

    The goal of Carnegie "Challenge" papers is to lift up ideas and issues in a way that elevates them to the nation's agenda. This paper is a "Challenge" paper, and serves as a call to realize the full power of the Common Core by redesigning and reshaping schools to support teachers and maximize key resources, rather than…

  19. Challenges in Mentoring Software Development Projects in the High School: Analysis According to Shulman's Teacher Knowledge Base Model

    Science.gov (United States)

    Meerbaum-Salant, Orni; Hazzan, Orit

    2009-01-01

    This paper focuses on challenges in mentoring software development projects in the high school and analyzes difficulties encountered by Computer Science teachers in the mentoring process according to Shulman's Teacher Knowledge Base Model. The main difficulties that emerged from the data analysis belong to the following knowledge sources of…

  20. Flight Control of the High Altitude Wind Power System

    NARCIS (Netherlands)

    Podgaets, A.R.; Ockels, W.J.

    2007-01-01

    Closed loop Laddermill flight control problem is considered in this paper. Laddermill is a high altitude kites system for energy production. The kites have been simulated as rigid bodies and the cable as a thin elastic line. Euler angles and cable speed are controls. Flight control is written as a

  1. Nonlinear Multivariate Spline-Based Control Allocation for High-Performance Aircraft

    OpenAIRE

    Tol, H.J.; De Visser, C.C.; Van Kampen, E.; Chu, Q.P.

    2014-01-01

    High performance flight control systems based on the nonlinear dynamic inversion (NDI) principle require highly accurate models of aircraft aerodynamics. In general, the accuracy of the internal model determines to what degree the system nonlinearities can be canceled; the more accurate the model, the better the cancellation, and with that, the higher the performance of the controller. In this paper a new control system is presented that combines NDI with multivariate simplex spline based con...

  2. Driver Response Times when Resuming Manual Control from Highly Automated Driving in Truck Platooning Scenarios.

    NARCIS (Netherlands)

    Zhang, Bo; Wilschut, Ellen; Willemsen, D.; Martens, Marieke

    2017-01-01

    Automated platooning of trucks is getting increasing interest for its potentially beneficial effects on fuel consumption, driver workload, traffic flow efficiency and safety. Nevertheless, one major challenge lies in the safe and comfortable transitions of control from the automated system back to

  3. Histamine and tryptase in nasal lavage fluid after allergen challenge

    DEFF Research Database (Denmark)

    Jacobi, H H; Skov, P S; Poulsen, L K

    1999-01-01

    BACKGROUND: Antihistamines (H1-receptor antagonists) act by competitive antagonism of histamine at H1-receptors. In addition, high concentrations of some antihistamines inhibit allergen-induced histamine release from mast cells in vitro. OBJECTIVE: The purpose of this study was to determine...... the effect of intranasal azelastine or systemic cetirizine (both potent antihistamines) on the allergen-induced release of mast-cell mediators from the human nasal mucosa in vivo. METHODS: Patients allergic to birch pollen (n = 11) and control subjects not allergic to birch pollen (n = 5) were included......, nasal allergen challenges were performed, and the number of sneezes were counted. In addition, nasal lavage fluid was collected, and the levels of mast-cell mediators (histamine and tryptase) were measured. RESULTS: The allergen challenge of patients allergic to pollen produced sneezing...

  4. Classical swine fever (CSF) marker vaccine - Trial I. Challenge studies in weaner pigs

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Le Potier, M.F.; Romero, L.

    2001-01-01

    , -10 or -7, and subsequently challenged at day 0. The challenge virus was CSFV 277, originating from a recent outbreak of classical swine fever (CSF) in Germany. In all groups, only 5 out of 10 pigs were challenged; the remaining 5 pigs served as vaccinated contact controls. Also, three control groups...

  5. Development of high-reliability control system for nuclear power plants

    International Nuclear Information System (INIS)

    Asami, K.; Yanai, K.; Hirose, H.; Ito, T.

    1983-01-01

    In Japan, many nuclear power generating plants are in operation and under construction. There is a general awareness of the problems in connection with nuclear power generation and strong emphasis is put on achieving highly reliable operation of nuclear power plants. Hitachi has developed a new high-reliability control system. NURECS-3000 (NUclear Power Plant High-REliability Control System), which is applied to the main control systems, such as the reactor feedwater control system, the reactor recirculation control system and the main turbine control system. The NURECS-3000 system was designed taking into account the fact that there will be failures, but the aim is for the system to continue to function correctly; it is therefore a fault-tolerant system. It has redundant components which can be completely isolated from each other in order to prevent fault propagation. The system has a hierarchical configuration, with a main controller, consisting of a triplex microcomputer system, and sub-loop controllers. Special care was taken to ensure the independence of these subsystems. Since most of the redundant system failures are caused by common-mode failures and the reliability of redundant systems depends on the reliability of the common-mode parts, the aim was to minimize these parts. (author)

  6. Reasoning about Control Situations in Power Systems

    DEFF Research Database (Denmark)

    Saleem, Arshad; Lind, Morten

    2009-01-01

    Introduction of distributed generation, deregulation and distribution of control has brought new challenges for electric power system operation, control and automation. Traditional power system models used in reasoning tasks such as intelligent control are highly dependent on the task purpose. Thus......, a model for intelligent control must represent system features, so that information from measurements can be related to possible system states and to control actions. These general modeling requirements are well understood, but it is, in general, difficult to translate them into a model because...

  7. Memory B cells and CD8⁺ lymphocytes do not control seasonal influenza A virus replication after homologous re-challenge of rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Timothy D Carroll

    Full Text Available This study sought to define the role of memory lymphocytes in the protection from homologous influenza A virus re-challenge in rhesus macaques. Depleting monoclonal antibodies (mAb were administered to the animals prior to their second experimental inoculation with a human seasonal influenza A virus strain. Treatment with either anti-CD8α or anti-CD20 mAbs prior to re-challenge had minimal effect on influenza A virus replication. Thus, in non-human primates with pre-existing anti-influenza A antibodies, memory B cells and CD8α⁺ T cells do not contribute to the control of virus replication after re-challenge with a homologous strain of influenza A virus.

  8. A microcontroller application as X-ray machine's high voltage controller

    International Nuclear Information System (INIS)

    Wiranto Budi Santoso; Beny Syawaludin

    2010-01-01

    A micro controller application as x-ray machine's high voltage controller has been carried out. The purpose of this micro controller application is to give an accurate high voltage supply to the x-ray tube so that the x-ray machine could produce the result as expected. The micro controller based X-ray machine's high voltage controller receives an input voltage from the keypad. This input value is displayed in the LCD (Liquid Crystal Display) screen. Then micro controller uses this input data to drive a stepper motor. The stepper motor adjusts the high voltage auto transformer's output according to the input value. The micro controller is programmed using BASCOM-8051 compiler. The test results show that the stepper motor could rotate according to an input value (author)

  9. Towards eliminating malaria in high endemic countries: the roles of community health workers and related cadres and their challenges in integrated community case management for malaria: a systematic review.

    Science.gov (United States)

    Sunguya, Bruno F; Mlunde, Linda B; Ayer, Rakesh; Jimba, Masamine

    2017-01-03

    Human resource for health crisis has impaired global efforts against malaria in highly endemic countries. To address this, the World Health Organization (WHO) recommended scaling-up of community health workers (CHWs) and related cadres owing to their documented success in malaria and other disease prevention and management. Evidence is inconsistent on the roles and challenges they encounter in malaria interventions. This systematic review aims to summarize evidence on roles and challenges of CHWs and related cadres in integrated community case management for malaria (iCCM). This systematic review retrieved evidence from PubMed, CINAHL, ISI Web of Knowledge, and WHO regional databases. Terms extracted from the Boolean phrase used for PubMed were also used in other databases. The review included studies with Randomized Control Trial, Quasi-experimental, Pre-post interventional, Longitudinal and cohort, Cross-sectional, Case study, and Secondary data analysis. Because of heterogeneity, only narrative synthesis was conducted for this review. A total of 66 articles were eligible for analysis out of 1380 studies retrieved. CHWs and related cadre roles in malaria interventions included: malaria case management, prevention including health surveillance and health promotion specific to malaria. Despite their documented success, CHWs and related cadres succumb to health system challenges. These are poor and unsustainable finance for iCCM, workforce related challenges, lack of and unsustainable supply of medicines and diagnostics, lack of information and research, service delivery and leadership challenges. Community health workers and related cadres had important preventive, case management and promotive roles in malaria interventions. To enable their effective integration into the health systems, the identified challenges should be addressed. They include: introducing sustainable financing on iCCM programmes, tailoring their training to address the identified gaps

  10. Challenge for lowering concentration polarization in solid oxide fuel cells

    Science.gov (United States)

    Shimada, Hiroyuki; Suzuki, Toshio; Yamaguchi, Toshiaki; Sumi, Hirofumi; Hamamoto, Koichi; Fujishiro, Yoshinobu

    2016-01-01

    In the scope of electrochemical phenomena, concentration polarization at electrodes is theoretically inevitable, and lowering the concentration overpotential to improve the performance of electrochemical cells has been a continuing challenge. Electrodes with highly controlled microstructure, i.e., high porosity and uniform large pores are therefore essential to achieve high performance electrochemical cells. In this study, state-of-the-art technology for controlling the microstructure of electrodes has been developed for realizing high performance support electrodes of solid oxide fuel cells (SOFCs). The key is controlling the porosity and pore size distribution to improve gas diffusion, while maintaining the integrity of the electrolyte and the structural strength of actual sized electrode supports needed for the target application. Planar anode-supported SOFCs developed in this study realize 5 μm thick dense electrolyte (yttria-stabilized zirconia: YSZ) and the anode substrate (Ni-YSZ) of 53.6 vol.% porosity with a large median pore diameter of 0.911 μm. Electrochemical measurements reveal that the performance of the anode-supported SOFCs improves with increasing anode porosity. This Ni-YSZ anode minimizes the concentration polarization, resulting in a maximum power density of 3.09 W cm-2 at 800 °C using humidified hydrogen fuel without any electrode functional layers.

  11. A Challenge-Based Approach to Body Weight-Supported Treadmill Training Poststroke: Protocol for a Randomized Controlled Trial.

    Science.gov (United States)

    Naidu, Avantika; Brown, David; Roth, Elliot

    2018-05-03

    Body weight support treadmill training protocols in conjunction with other modalities are commonly used to improve poststroke balance and walking function. However, typical body weight support paradigms tend to use consistently stable balance conditions, often with handrail support and or manual assistance. In this paper, we describe our study protocol, which involved 2 unique body weight support treadmill training paradigms of similar training intensity that integrated dynamic balance challenges to help improve ambulatory function post stroke. The first paradigm emphasized walking without any handrails or manual assistance, that is, hands-free walking, and served as the control group, whereas the second paradigm incorporated practicing 9 essential challenging mobility skills, akin to environmental barriers encountered during community ambulation along with hands-free walking (ie hands-free + challenge walking). We recruited individuals with chronic poststroke hemiparesis and randomized them to either group. Participants trained for 6 weeks on a self-driven, robotic treadmill interface that provided body weight support and a safe gait-training environment. We assessed participants at pre-, mid- and post 6 weeks of intervention-training, with a 6-month follow-up. We hypothesized greater walking improvements in the hands-free + challenge walking group following training because of increased practice opportunity of essential mobility skills along with hands-free walking. We assessed 77 individuals with chronic hemiparesis, and enrolled and randomized 30 individuals poststroke for our study (hands-free group=19 and hands-free + challenge walking group=20) from June 2012 to January 2015. Data collection along with 6-month follow-up continued until January 2016. Our primary outcome measure is change in comfortable walking speed from pre to post intervention for each group. We will also assess feasibility, adherence, postintervention efficacy, and changes in various

  12. Insight into Alternative Approaches for Control of Avian Influenza in Poultry, with Emphasis on Highly Pathogenic H5N1

    Directory of Open Access Journals (Sweden)

    Hafez M. Hafez

    2012-11-01

    Full Text Available Highly pathogenic avian influenza virus (HPAIV of subtype H5N1 causes a devastating disease in poultry but when it accidentally infects humans it can cause death. Therefore, decrease the incidence of H5N1 in humans needs to focus on prevention and control of poultry infections. Conventional control strategies in poultry based on surveillance, stamping out, movement restriction and enforcement of biosecurity measures did not prevent the virus spreading, particularly in developing countries. Several challenges limit efficiency of the vaccines to prevent outbreaks of HPAIV H5N1 in endemic countries. Alternative and complementary approaches to reduce the current burden of H5N1 epidemics in poultry should be encouraged. The use of antiviral chemotherapy and natural compounds, avian-cytokines, RNA interference, genetic breeding and/or development of transgenic poultry warrant further evaluation as integrated intervention strategies for control of HPAIV H5N1 in poultry.

  13. Key regulatory challenges for future nuclear power plants

    International Nuclear Information System (INIS)

    Todreas, Neil E.

    2001-01-01

    Key regulatory challenges for future nuclear power plants are concerned with fuel and cladding materials taken to higher burnup and operated at higher temperatures. Particular challenges are related to reduction in waste toxicity, understanding and control of coolant corrosion, qualification of fuel particles, new maintenance practices

  14. Concepts for Distributed Engine Control

    Science.gov (United States)

    Culley, Dennis E.; Thomas, Randy; Saus, Joseph

    2007-01-01

    Gas turbine engines for aero-propulsion systems are found to be highly optimized machines after over 70 years of development. Still, additional performance improvements are sought while reduction in the overall cost is increasingly a driving factor. Control systems play a vitally important part in these metrics but are severely constrained by the operating environment and the consequences of system failure. The considerable challenges facing future engine control system design have been investigated. A preliminary analysis has been conducted of the potential benefits of distributed control architecture when applied to aero-engines. In particular, reductions in size, weight, and cost of the control system are possible. NASA is conducting research to further explore these benefits, with emphasis on the particular benefits enabled by high temperature electronics and an open-systems approach to standardized communications interfaces.

  15. Transactive control: a framework for operating power systems characterized by high penetration of distributed energy resources

    DEFF Research Database (Denmark)

    Hu, Junjie; Yang, Guangya; Kok, Koen

    2016-01-01

    The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution network level, as well as increasing balancing needs at the whole system level......, followed by a literature review and demonstration projects that apply to transactive control. Cases are then presented to illustrate the transactive control framework. At the end, discussions and research directions are presented, for applying transactive control to operating power systems, characterized...

  16. On Challenges for Hypersonic Turbulent Simulations

    International Nuclear Information System (INIS)

    Yee, H.C.; Sjogreen, B.

    2009-01-01

    This short note discusses some of the challenges for design of suitable spatial numerical schemes for hypersonic turbulent flows, including combustion, and thermal and chemical nonequilibrium flows. Often, hypersonic turbulent flows in re-entry space vehicles and space physics involve mixed steady strong shocks and turbulence with unsteady shocklets. Material mixing in combustion poses additional computational challenges. Proper control of numerical dissipation in numerical methods beyond the standard shock-capturing dissipation at discontinuities is an essential element for accurate and stable simulations of the subject physics. On one hand, the physics of strong steady shocks and unsteady turbulence/shocklet interactions under the nonequilibrium environment is not well understood. On the other hand, standard and newly developed high order accurate (fourth-order or higher) schemes were developed for homogeneous hyperbolic conservation laws and mixed hyperbolic and parabolic partial differential equations (PDEs) (without source terms). The majority of finite rate chemistry and thermal nonequilibrium simulations employ methods for homogeneous time-dependent PDEs with a pointwise evaluation of the source terms. The pointwise evaluation of the source term might not be the best choice for stability, accuracy and minimization of spurious numerics for the overall scheme

  17. Design and Control of Integrated Systems for Hydrogen Production and Power Generation

    Science.gov (United States)

    Georgis, Dimitrios

    Growing concerns on CO2 emissions have led to the development of highly efficient power plants. Options for increased energy efficiencies include alternative energy conversion pathways, energy integration and process intensification. Solid oxide fuel cells (SOFC) constitute a promising alternative for power generation since they convert the chemical energy electrochemically directly to electricity. Their high operating temperature shows potential for energy integration with energy intensive units (e.g. steam reforming reactors). Although energy integration is an essential tool for increased efficiencies, it leads to highly complex process schemes with rich dynamic behavior, which are challenging to control. Furthermore, the use of process intensification for increased energy efficiency imposes an additional control challenge. This dissertation identifies and proposes solutions on design, operational and control challenges of integrated systems for hydrogen production and power generation. Initially, a study on energy integrated SOFC systems is presented. Design alternatives are identified, control strategies are proposed for each alternative and their validity is evaluated under different operational scenarios. The operational range of the proposed control strategies is also analyzed. Next, thermal management of water gas shift membrane reactors, which are a typical application of process intensification, is considered. Design and operational objectives are identified and a control strategy is proposed employing advanced control algorithms. The performance of the proposed control strategy is evaluated and compared with classical control strategies. Finally SOFC systems for combined heat and power applications are considered. Multiple recycle loops are placed to increase design flexibility. Different operational objectives are identified and a nonlinear optimization problem is formulated. Optimal designs are obtained and their features are discussed and compared

  18. Opportunities and challenges in green house gases reduction using high pressure direct injection of natural gas

    International Nuclear Information System (INIS)

    Ouellette, P.

    2001-01-01

    In an effort to reduce Greenhouse Gases, Westport Innovations is developing a high pressure direct injection (HPDI) technology for gaseous fuels. This technology adapts the diesel cycle for gaseous fuels, since the diesel cycle provides high efficiency, high low-speed torque, fast transient capabilities and reliability. Because of their high efficiency, diesels are very favorable from a Greenhouse Gas (GHG) point of view, however they remain challenged by high nitrogen oxides (NOx) and particulate matter (PM) emissions. When directly injecting natural gas, NOx and PM emissions can be reduced by approximately 50% while maintaining the performance of the diesel engine. This allows the use of abundant and historically cheaper natural gas. Because of its lower carbon content per unit energy, natural gas also offers further GHG reduction over the diesel if the efficiency is preserved and if methane emissions are low. This paper discusses development efforts at Westport for several applications including on-highway trucks, light-duty delivery trucks and power generation

  19. Mathematical models for lymphatic filariasis transmission and control: Challenges and prospects

    Directory of Open Access Journals (Sweden)

    Kaliannagounder Krishnamoorthy

    2008-02-01

    Full Text Available Abstract Background Mathematical models developed for describing the dynamics of transmission, infection, disease and control of lymphatic filariasis (LF gained momentum following the 1997 World Health Assembly resolution and the launching of the Global Programme to Eliminate Lymphatic Filariasis (GPELF in 2000. Model applications could provide valuable inputs for making decisions while implementing large scale programmes. However these models need to be evaluated at different epidemiological settings for optimization and fine-tuning with new knowledge and understanding on infection/disease dynamics. Discussion EPIFIL and LYMFASIM are the two mathematical simulation models currently available for lymphatic filariasis transmission and control. Both models have been used for prediction and evaluation of control programmes under research settings. Their widespread application in evaluating large-scale elimination programmes warrants validation of assumptions governing the dynamics of infection and disease in different epidemiological settings. Furthermore, the predictive power of the models for decision support can be enhanced by generating knowledge on some important issues that pose challenges and incorporating such knowledge into the models. We highlight factors related to the efficacy of the drugs of choice, their mode of action, and the possibility that drug resistance may develop; the role of vector-parasite combinations; the magnitude of transmission thresholds; host-parasite interactions and their effects on the dynamics of infection and immunity; parasite biology, and progression to LF-associated disease. Summary The two mathematical models developed offer potential decision making tools for transmission and control of LF. In view of the goals of the GPELF, the predictive power of these models needs to be enhanced for their wide-spread application in large scale programmes. Assimilation and translation of new information into the models is

  20. Methane emissions from a high arctic valley: findings and challenges

    DEFF Research Database (Denmark)

    Mastepanov, Mikhail; Sigsgaard, Charlotte; Ström, Lena

    2008-01-01

    Wet tundra ecosystems are well-known to be a significant source of atmospheric methane. With the predicted stronger effect of global climate change on arctic terrestrial ecosystems compared to lower-latitudes, there is a special obligation to study the natural diversity and the range of possible...... feedback effects on global climate that could arise from Arctic tundra ecosystems. One of the prime candidates for such a feedback mechanism is a potential change in the emissions of methane. Long-term datasets on methane emissions from high arctic sites are almost non-existing but badly needed...... for analyses of controls on interannual and seasonal variations in emissions. To help fill this gap we initiated a measurement program in a productive high arctic fen in the Zackenberg valley, NE Greenland. Methane flux measurements have been carried out at the same location since 1997. Compared...

  1. Challenges for development and provision of metrological quality control tools in nuclear safeguards, nuclear forensics and nuclear security

    International Nuclear Information System (INIS)

    Aregbe, Y.; Richter, S.; Jakopic, R.; Bauwens, J.; Truyens, J.; Sturm, M.; Bujak, R.; Eykens, R.; Kehoe, F.; Kuehn, H.; Hennessy, C.

    2013-01-01

    Joint advancements in quality control tools and measurement sciences of international reference and safeguards laboratories include: -) successful integration of the Modified Total Evaporation technique (MTE) as a new tool for routine thermal ionization mass spectrometry in nuclear safeguards and security, -) research and feasibility studies for the development of new materials standard, particularly for nuclear forensics (Certified Reference Materials - CRMs for age-dating), -) quality control tools to support the additional protocol and nuclear security (particle CRMs, NUSIMEP (inter-laboratory comparisons for U particle analysis), and -) scientific/technical advice, training and knowledge transfer. The European Safeguards Research and Development Association (ESARDA), the Institute of Nuclear Materials Management (INMM) and the CETAMA Commission from the French Commission of Atomic Energy and Alternative Energies (CEA/CETAMA) and the International Atomic Energy Agency (IAEA) Technical Meetings are the platforms to exchange views on the needs and challenges for new Quality Control tools for nuclear safeguards and security. The paper is followed by the slides of the presentation

  2. Technology Requirements and Development for Affordable High-Temperature Distributed Engine Controls

    Science.gov (United States)

    2012-06-04

    long lasting, high temperature modules is to use high temperature electronics on ceramic modules. The electronic components are “ brazed ” onto the...Copyright © 2012 by ISA Technology Requirements and Development for Affordable High - Temperature Distributed Engine Controls Alireza Behbahani 1...with regards to high temperature capability. The Government and Industry Distributed Engine Controls Working Group (DECWG) [5] has been established

  3. Addressing professional resource challenges facing modern utilities with technological solutions

    Energy Technology Data Exchange (ETDEWEB)

    Goldie, T. [Hydro One Networks Inc., Toronto, ON (Canada); Hodder, S. [GE Digital Energy, Toronto, ON (Canada)

    2008-07-01

    The challenges facing electric utilities regarding a shortage of highly qualified labour to maintain, refurbish and expand electrical infrastructure can be attributed to a wave of retirements in skilled employees, a shortage of entry-level workers and a rapidly increasing workload caused by investment in electricity infrastructure. Two solutions were presented for finding and sustaining an adequate personnel base. The first involved developing local talent, both entry-level and mid-career staff to ensure that work continuity and workplace safety are maintained. The second involved the implementation of technological solutions to help optimize the use of existing and future labour resources. This paper presented the human resource programs developed by Hydro One, the largest electrical transmission and distribution utility in the province of Ontario. Their initiatives include raising the profile of the utility work environment through strategic partnerships with educational institutions and developing in house offerings to supplement existing academic programs. This paper also presented a technical solution to address the resources challenges specifically associated with power system protection and control. The solution targets professional and skilled trades involved in the design, installation and maintenance of automated substations and protection and control systems. It is based on the premise that resource optimization can be achieved by reducing inconsistent design and construction practices and replacing these designs with highly standardized materials with digital communications using IEC 61850. This new technology should attract young professionals to the power engineering field while still maintaining a high comfort level with the established professional workforce. 5 refs., 4 figs.

  4. Transport of Spent Nuclear Fuels, High and Intermediate Level Wastes: A Continuous Challenge

    International Nuclear Information System (INIS)

    Otton, C.; Blachet, L.

    2009-01-01

    For more than 45 years TN International has been involved in the radioactive materials transportation field. Since the beginning the used nuclear fuel transportation has been its core business. During all these years TN International, now part of AREVA, has been able to anticipate and fulfil the needs for new transport or storage casks design to fit the nuclear industry evolutions. A whole fleet of casks able to transport all the materials of the nuclear fuel cycle has been developed. In this presentation we will focus on the casks for the spent fuel, high level waste and intermediate level waste transportation. Answering to the constant evolution of the nuclear industry transport needs is a challenge that TN International faces routinely. Concerning the spent nuclear fuel transportation, TN International has developed in the early 80's a fleet of TN12 type casks fitted with several types of baskets able to safely transport all the spent fuel from the nuclear power plant or the research laboratories to AREVA La Hague plant. The current challenge is the design of a new transport cask generation taking into account the needs of the industry for the next 30 years. The replacement of the TN12 cask generation is to be scheduled as the regulations have changed and the fuel characteristics have evolved. The new generation of casks will take into account all the technical evolutions made during the TN12 thirty years of use. MOX spent fuel has now its dedicated cask: the TN112 which certificate of approval has been obtained in July 2008. This cask is able to transport 12 MOX spent fuel elements with a short cooling time. The first loading of the cask has been performed in 2008 in the EDF nuclear power plant of Saint-Laurent-des-Eaux. Concerning the high level waste such as the La Hague vitrified residues a whole fleet of casks has been developed such as the TN 28 VT dedicated to transport, the TN81 and TN85 dedicated to transport and storage. These casks have permitted the

  5. Intestinal infection following aerosol challenge of calves with Mycobacterium avium subspecies paratuberculosis

    Directory of Open Access Journals (Sweden)

    Eisenberg Susanne WF

    2011-12-01

    Full Text Available Abstract A challenge experiment was performed to investigate whether administration of Mycobacterium avium subsp. paratuberculosis (MAP via the respiratory route leads to MAP infection in calves. Eighteen calves from test negative dams were randomly allocated to four groups. Six calves were challenged with MAP nasally and six calves were challenged by transtracheal injection; three orally challenged calves served as positive controls, and three non challenged calves as negative controls. The challenge was performed as a nine-fold trickle dose, 107 CFU in total. Blood and faecal samples were collected frequently. Calves were euthanized three months post-challenge and extensively sampled. Blood samples were tested for the presence of antibodies and interferon gamma producing cells by ELISA. Faecal and tissue samples were cultured in a liquid culture system and the presence of MAP was confirmed by IS900 realtime PCR. Fourteen out of fifteen calves had no MAP antibody response. The negative controls remained negative; all positive controls became infected. Two nasally challenged calves showed a Purified Protein Derivative Avian (PPDA specific interferon gamma response. In all nasally challenged calves, MAP positive intestinal samples were detected. In three calves of the nasal group MAP positive retropharyngeal lymph nodes or tonsils were detected. In all calves of the transtracheal group MAP positive intestinal tissues were detected as well and three had a MAP positive tracheobronchial lymph node. These findings indicate that inhalation of MAP aerosols can result in infection. These experimental results may be relevant for transmission under field conditions since viable MAP has been detected in dust on commercial dairy farms.

  6. High-powered CO2 -lasers and noise control

    Science.gov (United States)

    Honkasalo, Antero; Kuronen, Juhani

    High-power CO2 -lasers are being more and more widely used for welding, drilling and cutting in machine shops. In the near future, different kinds of surface treatments will also become routine practice with laser units. The industries benefitting most from high power lasers will be: the automotive industry, shipbuilding, the offshore industry, the aerospace industry, the nuclear and the chemical processing industries. Metal processing lasers are interesting from the point of view of noise control because the working tool is a laser beam. It is reasonable to suppose that the use of such laser beams will lead to lower noise levels than those connected with traditional metal processing methods and equipment. In the following presentation, the noise levels and possible noise-control problems attached to the use of high-powered CO2 -lasers are studied.

  7. Improving tuberculosis case detection in underdeveloped multi-ethnic regions with high disease burden: a case study of integrated control program in China.

    Science.gov (United States)

    Li, Jun; Liu, Xiao-Qiu; Jiang, Shi-Wen; Li, Xue; Yu, Fei; Wang, Yan; Peng, Yong; Gu, Xiao-Ming; Sun, Yan-Ni; Zhang, Hui; Wang, Li-Xia

    2017-11-29

    In the underdeveloped multi-ethnic regions of China, high tuberculosis (TB) burden and regional inequity in access to healthcare service increase the challenge of achieving the End TB goals. Among all the provinces, the highest TB burden is reported in Xinjiang, where ethnic minorities and older people have suffered most. However, current case-finding strategy is inadequate given the complex social determinants and suboptimal case detection rates. Thus, we developed an integrated TB control program to improve case detection and conducted a pilot in Xinjiang from 2014 to 2015. In this case study, we summarized the activities and key findings. We also shared the experiences and challenges of implementing interventions and provided recommendations to inform the TB control program in the future. The pilot interventions were implemented in one selected town in Yining based on local TB control programs. By applying tailor-made educational materials, outreach TB educational activities were conducted in diverse ways. In 22 Masjids, the trained imams promoted TB education to the Muslims, covering 20,440 person-times in 88 delivered preaching sessions. In seven schools, 1944 students were educated by the teachers and contributed to educating 6929 family members. In the village communities, 13,073 residents participated in household education and screening. Among them, 12,292 people aged under 65 years were investigated for suspicious pulmonary TB symptoms, where six TB patients were diagnosed out of 89 TB suspects; 781 older people were mobilized for screening directly by chest X-ray, where 10 patients were diagnosed out of 692 participants. Supportive healthcare system, multi-sectoral cooperation and multi-channel financing mechanism were the successful experiences of implementation. The interventions were proved to be more effective than the previous performance: the number of TB suspects consulting doctors and patients detected increased by 50% and 26%, respectively

  8. High performance current controller for particle accelerator magnets supply

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Bidoggia, Benoit; Munk-Nielsen, Stig

    2013-01-01

    The electromagnets in modern particle accelerators require high performance power supply whose output is required to track the current reference with a very high accuracy (down to 50 ppm). This demands very high bandwidth controller design. A converter based on buck converter topology is used...

  9. High resolution weather data for urban hydrological modelling and impact assessment, ICT requirements and future challenges

    Science.gov (United States)

    ten Veldhuis, Marie-claire; van Riemsdijk, Birna

    2013-04-01

    presentation will highlight ICT-related requirements and limitations in high resolution urban hydrological modelling and analysis. Further ICT challenges arise in provision of high resolution radar data for diverging information needs as well as in combination with other data sources in the urban environment. Different types of information are required for such diverse activities as operational flood protection, traffic management, large event organisation, business planning in shopping districts and restaurants, timing of family activities. These different information needs may require different configurations and data processing for radars and other data sources. An ICT challenge is to develop techniques for deciding how to automatically respond to these diverging information needs (e.g., through (semi-)automated negotiation). Diverse activities also provide a wide variety of information resources that can supplement traditional networks of weather sensors, such as rain sensors on cars and social media. Another ICT challenge is how to combine data from these different sources for answering a particular information need. Examples will be presented of solutions are currently being explored.

  10. New Challenges in Contamination Control: The Leadership Role ofIEST in Shaping Future Research and Practices.

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Tengfang; Eudy, Jane; Berndt, Charles

    2007-01-01

    A leading industrial standards writing organization since 1953, IEST has established seven tracks of Recommended Practices (RP) in the Standards and Practices (S&P) portion of the Contamination Control (CC) program, including the most recent program in Nanoscience and Nanotechnology. In addition, there are other parallel activities in IEST's Design, Test, and Evaluation and Product Reliability division. Within each of these programs, scientists, engineers, and contamination control professionals from all over the world interact closely in working group meetings, seminars, and tutorials. Together they have developed, published, and disseminated technical information and industrial standards, including RPs, Reference Documents (RDs), and ISO Standards to address ever evolving challenges in contamination control and sustainable development of the industries served by IEST. The series of Standards, RPs, and RDs are developed through years of discussion, deliberation and review thus providing peer-reviewed best practices, standardized procedures and test methods to furnish guidance and address problems in contamination control. In general, IEST's procedures for the development of Standards, RPs, or RDs are in accordance with its status as an ANSI-accredited Standards Developer Organization (SDO). Specifically, RPs and RDs are formulated by IEST Working Groups (WGs) through a cooperative exchange of knowledge, experience and ideas that culminate in useful and timely information invaluable to all that avail themselves of this knowledge. These documents are reviewed every three years so that new knowledge, information, and methods may be integrated into them in a timely manner. All WG member contributions are provided by professionals on a volunteer basis. There are increasing challenges associated with keeping up with new knowledge requirements. However, IEST has successfully relied on ever-evolving leadership and concerted efforts by numerous volunteers to

  11. Big data challenges: Impact, potential responses and research needs

    OpenAIRE

    Bachlechner, Daniel; Leimbach, Timo

    2016-01-01

    Although reports on big data success stories have been accumulating in the media, most organizations dealing with high-volume, high-velocity and high-variety information assets still face challenges. Only a thorough understanding of these challenges puts organizations into a position in which they can make an informed decision for or against big data, and, if the decision is positive, overcome the challenges smoothly. The combination of a series of interviews with leading experts from enterpr...

  12. Fractional high-harmonic combs by attosecond-precision split-spectrum pulse control

    Directory of Open Access Journals (Sweden)

    Laux Martin

    2013-03-01

    Full Text Available Few-cycle laser fields enable pulse-shaping control of high-order harmonic generation by time delaying variable broadband spectral sections. We report the experimental generation of fractional (noninteger high-harmonic combs by the controlled interference of two attosecond pulse trains. Additionally the energy of the high harmonics is strongly tuned with the relative time delay. We quantify the tuning to directly result from the controlled variation of the instantaneous laser frequency at the shaped driver pulse intensity maximum.

  13. People with chronic low back pain have poorer balance than controls in challenging tasks.

    Science.gov (United States)

    da Silva, Rubens A; Vieira, Edgar R; Fernandes, Karen B P; Andraus, Rodrigo A; Oliveira, Marcio R; Sturion, Leandro A; Calderon, Mariane G

    2018-06-01

    To compare the balance of individuals with and without chronic low back pain during five tasks. The participants were 20 volunteers, 10 with and 10 without nonspecific chronic low back pain, mean age 34 years, 50% females. The participants completed the following balance tasks on a force platform in random order: (1) two-legged stance with eyes open, (2) two-legged stance with eyes closed, (3) semi-tandem with eyes open, (4) semi-tandem with eyes closed and (5) one-legged stance with eyes open. The participants completed three 60-s trials of tasks 1-4, and three 30-s trials of task 5 with 30-s rests between trials. The center of pressure area, velocity and frequency in the antero-posterior and medio-lateral directions were computed during each task, and compared between groups and tasks. Participants with chronic low back pain presented significantly larger center of pressure area and higher velocity than the healthy controls (p chronic low back pain group than two-legged stance tasks 1 and 2 (effect size >1.37 vs. effect size chronic low back pain presented poorer postural control using center of pressure measurements than the healthy controls, mainly during more challenging balance tasks such as semi-tandem and one-legged stance conditions. Implications for Rehabilitation People with chronic low back had poorer balance than those without it. Balance tasks need to be sensitive to capture impairments. Balance assessments during semi-tandem and one-legged stance were the most sensitive tasks to determine postural control deficit in people with chronic low back. Balance assessment should be included during rehabilitation programs for individuals with chronic low back pain for better clinical decision making related to balance re-training as necessary.

  14. Architecting Web Sites for High Performance

    Directory of Open Access Journals (Sweden)

    Arun Iyengar

    2002-01-01

    Full Text Available Web site applications are some of the most challenging high-performance applications currently being developed and deployed. The challenges emerge from the specific combination of high variability in workload characteristics and of high performance demands regarding the service level, scalability, availability, and costs. In recent years, a large body of research has addressed the Web site application domain, and a host of innovative software and hardware solutions have been proposed and deployed. This paper is an overview of recent solutions concerning the architectures and the software infrastructures used in building Web site applications. The presentation emphasizes three of the main functions in a complex Web site: the processing of client requests, the control of service levels, and the interaction with remote network caches.

  15. Analysis of pastoralists' perception on challenges and opportunities for sheep and goat production in Northern Kenya.

    Science.gov (United States)

    Abdilatif, Mohamed Haji; Onono, Joshua Orungo; Mutua, Florence Kanini

    2018-05-16

    Small ruminants' production contributes to livelihood of pastoral communities, but this faces myriad constraints. This study aimed at identifying challenges facing producers of small ruminants, prioritizing diseases and their control measures and documenting opportunities for improvement. Sixteen focus group discussions with livestock owners and 13 key informant interviews were done in selected areas in Mandera County, Northern Kenya, and both quantitative and qualitative data collected using a questionnaire guide. Occurrences of diseases (27.4%) and drought (25%) were consistently ranked high in all groups. Other production challenges included increased predation of livestock, inadequate delivery of veterinary services, and increased livestock mortalities. Peste des Petit ruminants was ranked high with a median rank of 21.5%, while contagious caprine pleuropneumonia and sheep and goat pox were ranked second and third, respectively. Other diseases included tick-borne diseases, helminthosis, and pneumonia. Vaccination was ranked as the most effective control strategy for infectious diseases. Other control measures included recitation of Quran and cauterization. However, several opportunities exist for support of small ruminants' production: increased budgetary allocation for disease control by government, initiation of projects that enhance livestock production in the region by government and its development partners. These findings are useful for policy makers for disease control and organizations that are working on projects that focuses on enhancement of pastoralists' resilience, while future research could also identify appropriate technologies that reduces these impacts.

  16. Identification of Chinese Herbal Medicines with Electronic Nose Technology: Applications and Challenges.

    Science.gov (United States)

    Zhou, Huaying; Luo, Dehan; GholamHosseini, Hamid; Li, Zhong; He, Jiafeng

    2017-05-09

    This paper provides a review of the most recent works in machine olfaction as applied to the identification of Chinese Herbal Medicines (CHMs). Due to the wide variety of CHMs, the complexity of growing sources and the diverse specifications of herb components, the quality control of CHMs is a challenging issue. Much research has demonstrated that an electronic nose (E-nose) as an advanced machine olfaction system, can overcome this challenge through identification of the complex odors of CHMs. E-nose technology, with better usability, high sensitivity, real-time detection and non-destructive features has shown better performance in comparison with other analytical techniques such as gas chromatography-mass spectrometry (GC-MS). Although there has been immense development of E-nose techniques in other applications, there are limited reports on the application of E-noses for the quality control of CHMs. The aim of current study is to review practical implementation and advantages of E-noses for robust and effective odor identification of CHMs. It covers the use of E-nose technology to study the effects of growing regions, identification methods, production procedures and storage time on CHMs. Moreover, the challenges and applications of E-nose for CHM identification are investigated. Based on the advancement in E-nose technology, odor may become a new quantitative index for quality control of CHMs and drug discovery. It was also found that more research could be done in the area of odor standardization and odor reproduction for remote sensing.

  17. Heart rate responses to autonomic challenges in obstructive sleep apnea.

    Directory of Open Access Journals (Sweden)

    Paul M Macey

    Full Text Available Obstructive sleep apnea (OSA is accompanied by structural alterations and dysfunction in central autonomic regulatory regions, which may impair dynamic and static cardiovascular regulation, and contribute to other syndrome pathologies. Characterizing cardiovascular responses to autonomic challenges may provide insights into central nervous system impairments, including contributions by sex, since structural alterations are enhanced in OSA females over males. The objective was to assess heart rate responses in OSA versus healthy control subjects to autonomic challenges, and, separately, characterize female and male patterns. We studied 94 subjects, including 37 newly-diagnosed, untreated OSA patients (6 female, age mean ± std: 52.1 ± 8.1 years; 31 male aged 54.3 ± 8.4 years, and 57 healthy control subjects (20 female, 50.5 ± 8.1 years; 37 male, 45.6 ± 9.2 years. We measured instantaneous heart rate with pulse oximetry during cold pressor, hand grip, and Valsalva maneuver challenges. All challenges elicited significant heart rate differences between OSA and control groups during and after challenges (repeated measures ANOVA, p<0.05. In post-hoc analyses, OSA females showed greater impairments than OSA males, which included: for cold pressor, lower initial increase (OSA vs. control: 9.5 vs. 7.3 bpm in females, 7.6 vs. 3.7 bpm in males, OSA delay to initial peak (2.5 s females/0.9 s males, slower mid-challenge rate-of-increase (OSA vs. control: -0.11 vs. 0.09 bpm/s in females, 0.03 vs. 0.06 bpm/s in males; for hand grip, lower initial peak (OSA vs. control: 2.6 vs. 4.6 bpm in females, 5.3 vs. 6.0 bpm in males; for Valsalva maneuver, lower Valsalva ratio (OSA vs. control: 1.14 vs. 1.30 in females, 1.29 vs. 1.34 in males, and OSA delay during phase II (0.68 s females/1.31 s males. Heart rate responses showed lower amplitude, delayed onset, and slower rate changes in OSA patients over healthy controls, and impairments may be more pronounced in

  18. Control room philosophy: Principles of control room design and control room work

    International Nuclear Information System (INIS)

    Skriver, Jan; Ramberg, Jasmine; Allwin, Pernilla

    2006-01-01

    In order to provide insights for improvement of work in control rooms several factors have to be considered. Knowledge of principles including control room philosophies will guide the recommended improvements. In addition to knowledge about specific principles an advantage for an organization can be an understanding of similarities and policies used in other high risk industry. The report has been developed on the basis of a document analysis of international standards and other guiding documents. (NUREG 0711, ISO 11064, ISO 6385, IEC 60964). In addition to the document analysis which has strived to compare the documents to see similarities in important principals, experience from working with control room design, modifications and evaluations in other high risk industries has pervaded the report. Important principles have been identified which are recommended to be included in a control room philosophy. Many of these are similar to the principles identified in the international standards. An additional principal which is regarded as important is the utilization of Key Performance Indicators (KPI) which can be used as a measure to target preventative means. Further more it is critical that the control room philosophy is easy to access and comprehend for all users. One of the challenges that remain after having developed a control room philosophy is how to utilize it in the daily work situation. It is vital that the document remains as a living document, guiding the continual improvement of the control room in the various life cycle stages

  19. IBM-PC based high voltage controller [Paper No.: L7

    International Nuclear Information System (INIS)

    Mondal, N.K.; Kalmani, S.D.

    1993-01-01

    A simple IBM-PC/XT based high voltage controller is designed for C.A.E.N. high voltage supply unit, which is being used for testing the prototype detector for future accelerator experiment. The high voltage output of the supply unit can be remotely programmed. The V-set Lemo connectors at the rear panel provides the remote control facility. Similarly V-mon and I-mon can be used for remotely monitoring the voltage set and the current drawn from the supply unit. The controller described here sets the high voltage through V-set and monitors the voltage set, through V-mon at a pre-determined time interval. The monitoring is a background job and is done as an interrupt service routine of IRQ3. A simple menu driven software package used is written in Q-Basic and MASM. (author). 1 fig

  20. Circulating MicroRNAs in Serum from Cattle Challenged with Bovine Viral Diarrhea Virus‡

    Directory of Open Access Journals (Sweden)

    Tasia M. Taxis

    2017-06-01

    Full Text Available Bovine viral diarrhea virus (BVDV is an RNA virus that is often associated with respiratory disease in cattle. MicroRNAs have been proposed as indicators of exposure to respiratory pathogens. The objective of this study was to identify microRNAs in cattle that had been challenged with a non-cytopathic field strain of BVDV. Five colostrum deprived neonate Holstein calves were inoculated with BVDV (challenged and 4 were mock challenged (control. Serum from all calves was collected at four different times: prior to challenge (day 0 and at 4, 9, and 16 days post-challenge. RNA was extracted from sera, and expression, via read counts, of small non-coding RNAs were obtained using next-generation sequencing. A total of 905,861 sequences identified 427 microRNAs. Sixty-two microRNAs had >1,000 total reads across all samples. Bta-miR-339a, bta-miR-185, bta-miR-486, Bta-miR-92a, bta-miR-30e-5p, bta-let-7c, and bta-miR-2284x were significantly different (P < 0.05 across time regardless of challenge status. Bta-miR-423-5p (P = 0.008 and bta-miR-151-3p (P = 0.005 were significantly different between challenged and control animals across time. In challenged animals, bta-miR-423-5p peaked in number of reads by day 4 and steadily declined from day 4 to day 16. In control animals, bta-miR-423-5p declined from day 0 to day 9 and increased in number by day 16. By day 16, both challenged and control animals had similar levels of bta-miR-423-5p, and these levels were similar to day 0 levels. Bta-miR-151-3p peaked at day 9 in challenged animals, while control animals decreased across time. By day 16, the number of reads of bta-miR-151-3p were similar between challenged and control animals. The level in challenged animals had returned to day 0 levels by day 16, whereas the levels for control animals was significantly lower (P = 0.006 than day 0. Further studies are needed to establish if bta-miR-423-5p or bta-miR-151-3p could be used as a biomarker for exposure to

  1. Rapid prefrontal cortex activation towards aversively paired faces and enhanced contingency detection are observed in highly trait-anxious women under challenging conditions

    Science.gov (United States)

    Rehbein, Maimu Alissa; Wessing, Ida; Zwitserlood, Pienie; Steinberg, Christian; Eden, Annuschka Salima; Dobel, Christian; Junghöfer, Markus

    2015-01-01

    Relative to healthy controls, anxiety-disorder patients show anomalies in classical conditioning that may either result from, or provide a risk factor for, clinically relevant anxiety. Here, we investigated whether healthy participants with enhanced anxiety vulnerability show abnormalities in a challenging affective-conditioning paradigm, in which many stimulus-reinforcer associations had to be acquired with only few learning trials. Forty-seven high and low trait-anxious females underwent MultiCS conditioning, in which 52 different neutral faces (CS+) were paired with an aversive noise (US), while further 52 faces (CS−) remained unpaired. Emotional learning was assessed by evaluative (rating), behavioral (dot-probe, contingency report), and neurophysiological (magnetoencephalography) measures before, during, and after learning. High and low trait-anxious groups did not differ in evaluative ratings or response priming before or after conditioning. High trait-anxious women, however, were better than low trait-anxious women at reporting CS+/US contingencies after conditioning, and showed an enhanced prefrontal cortex (PFC) activation towards CS+ in the M1 (i.e., 80–117 ms) and M170 time intervals (i.e., 140–160 ms) during acquisition. These effects in MultiCS conditioning observed in individuals with elevated trait anxiety are consistent with theories of enhanced conditionability in anxiety vulnerability. Furthermore, they point towards increased threat monitoring and detection in highly trait-anxious females, possibly mediated by alterations in visual working memory. PMID:26113814

  2. Rapid prefrontal cortex activation towards aversively paired faces and enhanced contingency detection are observed in highly trait-anxious women under challenging conditions

    Directory of Open Access Journals (Sweden)

    Maimu Alissa Rehbein

    2015-06-01

    Full Text Available Relative to healthy controls, anxiety-disorder patients show anomalies in classical conditioning that may either result from, or provide a risk factor for, clinically relevant anxiety. Here, we investigated whether healthy participants with enhanced anxiety vulnerability show abnormalities in a challenging affective-conditioning paradigm, in which many stimulus-reinforcer associations had to be acquired with only few learning trials. Forty-seven high and low trait-anxious females underwent MultiCS conditioning, in which 52 different neutral faces (CS+ were paired with an aversive noise (US, while further 52 faces (CS- remained unpaired. Emotional learning was assessed by evaluative (rating, behavioral (dot-probe, contingency report, and neurophysiological (magnetoencephalography measures before, during, and after learning. High and low trait-anxious groups did not differ in evaluative ratings or response priming before or after conditioning. High trait-anxious women, however, were better than low trait-anxious women at reporting CS+/US contingencies after conditioning, and showed an enhanced prefrontal cortex activation towards CS+ in the M1 (i.e., 80 to 117 ms and M170 time intervals (i.e., 140 to 160 ms during acquisition. These effects in MultiCS conditioning observed in individuals with elevated trait anxiety are consistent with theories of enhanced conditionability in anxiety vulnerability. Furthermore, they point towards increased threat monitoring and detection in highly trait-anxious females, possibly mediated by alterations in visual working memory.

  3. Participation of Flexible Loads in Load Frequency Control to Support High Wind Penetration

    DEFF Research Database (Denmark)

    Uslu, Umur; Zhang, Boyang; Pillai, Jayakrishnan Radhakrishna

    2016-01-01

    The increasing amount of fluctuating wind power penetration in power systems presents many challenges to its operation and control. The new wind power plants are replacing many of the conventional large power plants that ensure power balancing and ancillary services for stable and reliable...... operation of the grid. Therefore, new solutions for power balancing reserves have to be explored and utilized by the grid utilities. To meet these challenges, large sizable loads like alkaline electrolysers, heat pumps and electric vehicles which are gaining popularity can provide system support to the grid...... through their inherent flexibility and energy storage characteristics. This paper investigates the possibilities and potential of such flexible loads to participate in power system frequency regulation in a wind dominated power system. The results show that these consumption units provide better...

  4. High-temperature controlled atmosphere for post-harvest control of Indian meal moth (Lepidoptera: Pyralidae) on preserved flowers.

    Science.gov (United States)

    Sauer, Jodi A; Shelton, Mark D

    2002-10-01

    High carbon dioxide atmospheres combined with high temperature were effective for controlling Indian meal moth, Plodia interpunctella (Hübner) pupae. Pupae were exposed to atmospheres of 60, 80, or 98% carbon dioxide (CO2) in nitrogen (N2), or 60 or 80% CO2 in air at temperatures of 26.7 degrees C or 32.2 degrees C and 60% RH. Controlled atmosphere treatments at 32.2 degrees C controlled pupae faster than the same treatments at the lower temperature. At both temperatures high CO2 concentration treatments combined with nitrogen killed pupae faster than high CO2 concentration treatments combined with air. Exposure to 80% carbon dioxide mixed with nitrogen was the most effective treatment causing 100% mortality in 12 h at 32.2 degrees C and 93.3% mortality in 18 h at 26.6 degrees C. High-temperature controlled atmosphere treatments had no adverse effects on quality of two preserved floral products, Limonium sinuatum (L.) and Gypsophila elegans (Bieb.), tested for 12, 18, and 24 h according to industry standards.

  5. Cassini Attitude and Articulation Control Subsystem Fault Protection Challenges During Saturn Proximal Orbits

    Science.gov (United States)

    Bates, David M.

    2015-01-01

    NASA's Cassini Spacecraft, launched on October 15th, 1997 arrived at Saturn on June 30th, 2004, is the largest and most ambitious interplanetary spacecraft in history. As the first spacecraft to achieve orbit at Saturn, Cassini has collected science data throughout its four-year prime mission (2004-08), and has since been approved for a first and second extended mission through 2017. As part of the final extended mission, Cassini will begin an aggressive and exciting campaign of high inclination low altitude flybys within the inner most rings of Saturn, skimming Saturn's outer atmosphere, until the spacecraft is finally disposed of via planned impact with the planet. This final campaign, known as the proximal orbits, presents unique fault protection related challenges, the details of which are discussed in this paper.

  6. Highly accurate prediction of food challenge outcome using routinely available clinical data.

    Science.gov (United States)

    DunnGalvin, Audrey; Daly, Deirdre; Cullinane, Claire; Stenke, Emily; Keeton, Diane; Erlewyn-Lajeunesse, Mich; Roberts, Graham C; Lucas, Jane; Hourihane, Jonathan O'B

    2011-03-01

    Serum specific IgE or skin prick tests are less useful at levels below accepted decision points. We sought to develop and validate a model to predict food challenge outcome by using routinely collected data in a diverse sample of children considered suitable for food challenge. The proto-algorithm was generated by using a limited data set from 1 service (phase 1). We retrospectively applied, evaluated, and modified the initial model by using an extended data set in another center (phase 2). Finally, we prospectively validated the model in a blind study in a further group of children undergoing food challenge for peanut, milk, or egg in the second center (phase 3). Allergen-specific models were developed for peanut, egg, and milk. Phase 1 (N = 429) identified 5 clinical factors associated with diagnosis of food allergy by food challenge. In phase 2 (N = 289), we examined the predictive ability of 6 clinical factors: skin prick test, serum specific IgE, total IgE minus serum specific IgE, symptoms, sex, and age. In phase 3 (N = 70), 97% of cases were accurately predicted as positive and 94% as negative. Our model showed an advantage in clinical prediction compared with serum specific IgE only, skin prick test only, and serum specific IgE and skin prick test (92% accuracy vs 57%, and 81%, respectively). Our findings have implications for the improved delivery of food allergy-related health care, enhanced food allergy-related quality of life, and economized use of health service resources by decreasing the number of food challenges performed. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  7. Reactivity control system of the high temperature engineering test reactor

    International Nuclear Information System (INIS)

    Tachibana, Yukio; Sawahata, Hiroaki; Iyoku, Tatsuo; Nakazawa, Toshio

    2004-01-01

    The reactivity control system of the high temperature engineering test reactor (HTTR) consists of a control rod system and a reserve shutdown system. During normal operation, reactivity is controlled by the control rod system, which consists of 32 control rods (16 pairs) and 16 control rod drive mechanisms except for the case when the center control rods are removed to perform an irradiation test. In an unlikely event that the control rods fail to be inserted, reserve shutdown system is provided to insert pellets of neutron-absorbing material into the core. Alloy 800H is chosen for the metallic parts of the control rods. Because the maximum temperature of the control rods reaches about 900 deg. C at reactor scrams, structural design guideline and design material data on Alloy 800H are needed for the high temperature design. The design guideline for the HTTR control rod is based on ASME Code Case N-47-21. Design material data is also determined and shown in this paper. Observing the guideline, temperature and stress analysis were conducted; it can be confirmed that the target life of the control rods of 5 years can be achieved. Various tests conducted for the control rod system and the reserve shutdown system are also described

  8. CLARAty: Challenges and Steps Toward Reusable Robotic Software

    Directory of Open Access Journals (Sweden)

    Richard Madison

    2008-11-01

    Full Text Available We present in detail some of the challenges in developing reusable robotic software. We base that on our experience in developing the CLARAty robotics software, which is a generic object-oriented framework used for the integration of new algorithms in the areas of motion control, vision, manipulation, locomotion, navigation, localization, planning and execution. CLARAty was adapted to a number of heterogeneous robots with different mechanisms and hardware control architectures. In this paper, we also describe how we addressed some of these challenges in the development of the CLARAty software.

  9. CLARAty: Challenges and Steps toward Reusable Robotic Software

    Directory of Open Access Journals (Sweden)

    Issa A.D. Nesnas

    2006-03-01

    Full Text Available We present in detail some of the challenges in developing reusable robotic software. We base that on our experience in developing the CLARAty robotics software, which is a generic object-oriented framework used for the integration of new algorithms in the areas of motion control, vision, manipulation, locomotion, navigation, localization, planning and execution. CLARAty was adapted to a number of heterogeneous robots with different mechanisms and hardware control architectures. In this paper, we also describe how we addressed some of these challenges in the development of the CLARAty software.

  10. High Resolution Sensing and Control of Urban Water Networks

    Science.gov (United States)

    Bartos, M. D.; Wong, B. P.; Kerkez, B.

    2016-12-01

    We present a framework to enable high-resolution sensing, modeling, and control of urban watersheds using (i) a distributed sensor network based on low-cost cellular-enabled motes, (ii) hydraulic models powered by a cloud computing infrastructure, and (iii) automated actuation valves that allow infrastructure to be controlled in real time. This platform initiates two major advances. First, we achieve a high density of measurements in urban environments, with an anticipated 40+ sensors over each urban area of interest. In addition to new measurements, we also illustrate the design and evaluation of a "smart" control system for real-world hydraulic networks. This control system improves water quality and mitigates flooding by using real-time hydraulic models to adaptively control releases from retention basins. We evaluate the potential of this platform through two ongoing deployments: (i) a flood monitoring network in the Dallas-Fort Worth metropolitan area that detects and anticipates floods at the level of individual roadways, and (ii) a real-time hydraulic control system in the city of Ann Arbor, MI—soon to be one of the most densely instrumented urban watersheds in the United States. Through these applications, we demonstrate that distributed sensing and control of water infrastructure can improve flash flood predictions, emergency response, and stormwater contaminant mitigation.

  11. High-Stakes Testing in the Warm Heart of Africa:The Challenges and Successes of the Malawi National Examinations Board

    Directory of Open Access Journals (Sweden)

    Elias Chakwera

    2004-06-01

    Full Text Available In the United States, tests are held to high standards of quality. In developing countries such as Malawi, psychometricians must deal with these same high standards as well as several additional pressures such as widespread cheating, test administration difficulties due to challenging landscapes and poor resources, difficulties in reliably scoring performance assessments, and extreme scrutiny from political parties and the popular press. The purposes of this paper are to (a familiarize the measurement community in the US about Malawi’s assessment programs, (b discuss some of the unique challenges inherent in such a program, (c compare testing conditions and test administration formats between Malawi and the US, and (d provide suggestions for improving large-scale testing in countries such as the US and Malawi. By learning how a small country instituted and supports its current testing programs, a broader perspective on resolving current measurement problems throughout the world will emerge.

  12. Control Law Design for Twin Rotor MIMO System with Nonlinear Control Strategy

    Directory of Open Access Journals (Sweden)

    M. Ilyas

    2016-01-01

    Full Text Available Modeling of complex air vehicles is a challenging task due to high nonlinear behavior and significant coupling effect between rotors. Twin rotor multi-input multioutput system (TRMS is a laboratory setup designed for control experiments, which resembles a helicopter with unstable, nonlinear, and coupled dynamics. This paper focuses on the design and analysis of sliding mode control (SMC and backstepping controller for pitch and yaw angle control of main and tail rotor of the TRMS under parametric uncertainty. The proposed control strategy with SMC and backstepping achieves all mentioned limitations of TRMS. Result analysis of SMC and backstepping control schemes elucidates that backstepping provides efficient behavior with the parametric uncertainty for twin rotor system. Chattering and oscillating behaviors of SMC are removed with the backstepping control scheme considering the pitch and yaw angle for TRMS.

  13. Automated blood glucose control in type 1 diabetes: A review of progress and challenges.

    Science.gov (United States)

    Bertachi, Arthur; Ramkissoon, Charrise M; Bondia, Jorge; Vehí, Josep

    2018-03-01

    Since the 2000s, research teams worldwide have been working to develop closed-loop (CL) systems able to automatically control blood glucose (BG) levels in patients with type 1 diabetes. This emerging technology is known as artificial pancreas (AP), and its first commercial version just arrived in the market. The main objective of this paper is to present an extensive review of the clinical trials conducted since 2011, which tested various implementations of the AP for different durations under varying conditions. A comprehensive table that contains key information from the selected publications is provided, and the main challenges in AP development and the mitigation strategies used are discussed. The development timelines for different AP systems are also included, highlighting the main evolutions over the clinical trials for each system. Copyright © 2017 SEEN y SED. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Statistical Challenges in Modeling Big Brain Signals

    KAUST Repository

    Yu, Zhaoxia; Pluta, Dustin; Shen, Tong; Chen, Chuansheng; Xue, Gui; Ombao, Hernando

    2017-01-01

    Brain signal data are inherently big: massive in amount, complex in structure, and high in dimensions. These characteristics impose great challenges for statistical inference and learning. Here we review several key challenges, discuss possible

  15. Vaccination with Plasmodium knowlesi AMA1 formulated in the novel adjuvant co-vaccine HT™ protects against blood-stage challenge in rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Muzamil Mahdi Abdel Hamid

    Full Text Available Plasmodium falciparum apical membrane antigen 1 (PfAMA1 is a leading blood stage vaccine candidate. Plasmodium knowlesi AMA1 (PkAMA1 was produced and purified using similar methodology as for clinical grade PfAMA1 yielding a pure, conformational intact protein. Combined with the adjuvant CoVaccine HT™, PkAMA1 was found to be highly immunogenic in rabbits and the efficacy of the PkAMA1 was subsequently tested in a rhesus macaque blood-stage challenge model. Six rhesus monkeys were vaccinated with PkAMA1 and a control group of 6 were vaccinated with PfAMA1. A total of 50 µg AMA1 was administered intramuscularly three times at 4 week intervals. One of six rhesus monkeys vaccinated with PkAMA1 was able to control parasitaemia, upon blood stage challenge with P. knowlesi H-strain. Four out of the remaining five showed a delay in parasite onset that correlated with functional antibody titres. In the PfAMA1 vaccinated control group, five out of six animals had to be treated with antimalarials 8 days after challenge; one animal did not become patent during the challenge period. Following a rest period, animals were boosted and challenged again. Four of the six rhesus monkeys vaccinated with PkAMA1 were able to control the parasitaemia, one had a delayed onset of parasitaemia and one animal was not protected, while all control animals required treatment. To confirm that the control of parasitaemia was AMA1-related, animals were allowed to recover, boosted and re-challenged with P. knowlesi Nuri strain. All control animals had to be treated with antimalarials by day 8, while five out of six PkAMA1 vaccinated animals were able to control parasitaemia. This study shows that: i Yeast-expressed PkAMA1 can protect against blood stage challenge; ii Functional antibody levels as measured by GIA correlated inversely with the day of onset and iii GIA IC(50 values correlated with estimated in vivo growth rates.

  16. Higgs Machine Learning Challenge 2014

    CERN Document Server

    Olivier, A-P; Bourdarios, C ; LAL / Orsay; Goldfarb, S ; University of Michigan

    2014-01-01

    High Energy Physics (HEP) has been using Machine Learning (ML) techniques such as boosted decision trees (paper) and neural nets since the 90s. These techniques are now routinely used for difficult tasks such as the Higgs boson search. Nevertheless, formal connections between the two research fields are rather scarce, with some exceptions such as the AppStat group at LAL, founded in 2006. In collaboration with INRIA, AppStat promotes interdisciplinary research on machine learning, computational statistics, and high-energy particle and astroparticle physics. We are now exploring new ways to improve the cross-fertilization of the two fields by setting up a data challenge, following the footsteps of, among others, the astrophysics community (dark matter and galaxy zoo challenges) and neurobiology (connectomics and decoding the human brain). The organization committee consists of ATLAS physicists and machine learning researchers. The Challenge will run from Monday 12th to September 2014.

  17. TB control programmes: the challenges for Africa.

    Science.gov (United States)

    Harries, T

    1996-11-01

    Governmental neglect of tuberculosis (TB), inadequately managed and inaccurately designed TB control programs, population growth, and the HIV epidemic account for the resurgence of TB in sub-Saharan Africa. The World Health Organization and the International Union against TB and Lung Disease have developed a TB control strategy that aims to reduce mortality, morbidity, and transmission of TB. It aims for an 85% cure rate among detected new cases of smear-positive TB and a 70% rate of detecting existing smear-positive TB cases. The strategy involves the provision of short-course chemotherapy (SCC) to all identified smear-positive TB cases through directly observed treatment (DOTS). SCC treatment regimens for smear-positive pulmonary TB recommended for sub-Saharan African countries are: initial phase = daily administration over 2 months of streptomycin, rifampicin, isoniazid, and pyrazinamide; continuation phase = 3 doses over 4 months of isoniazid and rifampicin or daily administration of thiacetazone and isoniazid or of ethambutol and isoniazid. A TB control policy must be implemented to bring about effective TB control. The essential elements of this policy include political commitment, case detection through passive case-finding, SCC, a regular supply of essential drugs, and a monitoring and evaluation system. Political commitment involves establishing a National TB Control Program to be integrated into the existing health structure. Increased awareness of TB in the community and among health workers and a reference laboratory are needed to make case finding successful. A distribution and logistics system is needed to ensure uninterrupted intake of drugs throughout treatment. These regimens have been very successful and cost-effective but pose several disadvantages (e.g., heavy workload of recommended 3 sputum smear tests). A simplified approach involves 1 initial sputum smear for 6 months; 6-months, intermittent rifampicin-based therapy, 100% DOTS throughout

  18. Characterizing challenged Minnesota ballots

    Science.gov (United States)

    Nagy, George; Lopresti, Daniel; Barney Smith, Elisa H.; Wu, Ziyan

    2011-01-01

    Photocopies of the ballots challenged in the 2008 Minnesota elections, which constitute a public record, were scanned on a high-speed scanner and made available on a public radio website. The PDF files were downloaded, converted to TIF images, and posted on the PERFECT website. Based on a review of relevant image-processing aspects of paper-based election machinery and on additional statistics and observations on the posted sample data, robust tools were developed for determining the underlying grid of the targets on these ballots regardless of skew, clipping, and other degradations caused by high-speed copying and digitization. The accuracy and robustness of a method based on both index-marks and oval targets are demonstrated on 13,435 challenged ballot page images.

  19. Dissociated control as a signature of typological variability in high hypnotic suggestibility.

    Science.gov (United States)

    Terhune, Devin Blair; Cardeña, Etzel; Lindgren, Magnus

    2011-09-01

    This study tested the prediction that dissociative tendencies modulate the impact of a hypnotic induction on cognitive control in different subtypes of highly suggestible individuals. Low suggestible (LS), low dissociative highly suggestible (LDHS), and high dissociative highly suggestible (HDHS) participants completed the Stroop color-naming task in control and hypnosis conditions. The magnitude of conflict adaptation (faster response times on incongruent trials preceded by an incongruent trial than those preceded by a congruent trial) was used as a measure of cognitive control. LS and LDHS participants displayed marginally superior up-regulation of cognitive control following a hypnotic induction, whereas HDHS participants' performance declined. These findings indicate that dissociative tendencies modulate the influence of a hypnotic induction on cognitive control in high hypnotic suggestibility and suggest that HS individuals are comprised of distinct subtypes with dissimilar cognitive profiles. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Impact of short-term high-fat feeding and insulin-stimulated FGF21 levels in subjects with low birth weight and controls

    DEFF Research Database (Denmark)

    Vienberg, Sara Gry; Brøns, Charlotte; Nilsson, Emma

    2012-01-01

    of type 2 diabetes and 26 control (normal birth weight (NBW)) young men were subjected to 5 days of high-fat (HF) overfeeding (+50%). Basal and clamp insulin-stimulated serum FGF21 levels were examined before and after the diet, and FGF21 mRNA expression was measured in muscle and fat biopsies......OBJECTIVE: Fibroblast growth factor 21 (FGF21) is a metabolic factor involved in glucose and lipid metabolism. However, little is known about the physiological role of FGF21 during a dietary challenge in humans. RESEARCH DESIGN AND METHODS: Twenty healthy low birth weight (LBW) with known risk...