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Sample records for instrumented mechanical impact

  1. Impact Disdrometers Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomew, Mary Jane [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-03-01

    To improve the quantitative description of precipitation processes in climate models, the U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) Climate Research Facility has been collecting observations of the drop size spectra of rain events since early in 2006. Impact disdrometers were the initial choice due to their reliability, ease of maintenance, and relatively low cost. Each of the two units deployed was accompanied by a nearby tipping bucket. In 2010, the tipping buckets were replaced by weighing buckets rain gauges. Five video disdrometers were subsequently purchased and are described in ARM’s VDIS Handbook.1 As of April 2011, three of the weighing bucket instruments were deployed, one was to travel with the second ARM Mobile Facility, and the fifth was a spare. Two of the video disdrometers were deployed, a third was to be deployed later in the spring of 2011, one was to travel with the second ARM Mobile Facility, and the last was a spare. Detailed descriptions of impact disdrometers and their datastreams are provided in this document.

  2. Impact Mechanics

    Science.gov (United States)

    Stronge, W. J.

    2004-03-01

    Impact mechanics is concerned with the reaction forces that develop during a collision and the dynamic response of structures to these reaction forces. The subject has a wide range of engineering applications, from designing sports equipment to improving the crashworthiness of automobiles. This book develops several different methodologies for analysing collisions between structures. These range from rigid body theory for structures that are stiff and compact, to vibration and wave analyses for flexible structures. The emphasis is on low-speed impact where damage is local to the small region of contact between the colliding bodies. The analytical methods presented give results that are more robust or less sensitive to initial conditions than have been achieved hitherto. As a text, Impact Mechanics builds upon foundation courses in dynamics and strength of materials. It includes numerous industrially relevant examples and end-of-chapter homework problems drawn from industry and sports. Practising engineers will also find the methods presented in this book useful in calculating the response of a mechanical system to impact.

  3. SMAP Instrument Mechanical System Engineering

    Science.gov (United States)

    Slimko, Eric; French, Richard; Riggs, Benjamin

    2013-01-01

    The Soil Moisture Active Passive (SMAP) mission, scheduled for launch by the end of 2014, is being developed to measure the soil moisture and soil freeze/thaw state on a global scale over a three-year period. The accuracy, resolution, and global coverage of SMAP measurements are invaluable across many science and applications disciplines including hydrology, climate, carbon cycle, and the meteorological, environment, and ecology applications communities. The SMAP observatory is composed of a despun bus and a spinning instrument platform that includes both a deployable 6 meter aperture low structural frequency Astromesh reflector and a spin control system. The instrument section has engendered challenging mechanical system issues associated with the antenna deployment, flexible antenna pointing in the context of a multitude of disturbances, spun section mass properties, spin control system development, and overall integration with the flight system on both mechanical and control system levels. Moreover, the multitude of organizations involved, including two major vendors providing the spin subsystem and reflector boom assembly plus the flight system mechanical and guidance, navigation, and control teams, has led to several unique system engineering challenges. Capturing the key physics associated with the function of the flight system has been challenging due to the many different domains that are applicable. Key interfaces and operational concepts have led to complex negotiations because of the large number of organizations that integrate with the instrument mechanical system. Additionally, the verification and validation concerns associated with the mechanical system have had required far-reaching involvement from both the flight system and other subsystems. The SMAP instrument mechanical systems engineering issues and their solutions are described in this paper.

  4. Mechanical engineers' handbook, design, instrumentation, and controls

    CERN Document Server

    Kutz, Myer

    2015-01-01

    Full coverage of electronics, MEMS, and instrumentation andcontrol in mechanical engineering This second volume of Mechanical Engineers' Handbookcovers electronics, MEMS, and instrumentation and control, givingyou accessible and in-depth access to the topics you'll encounterin the discipline: computer-aided design, product design formanufacturing and assembly, design optimization, total qualitymanagement in mechanical system design, reliability in themechanical design process for sustainability, life-cycle design,design for remanufacturing processes, signal processing, dataacquisition and dis

  5. Introduction: The effectiveness of impact assessment instruments

    OpenAIRE

    Cashmore, M; Bond, A; Sadler, B

    2009-01-01

    The global application of impact assessment instruments to achieve a variety of policy integration goals (e.g. the mainstreaming of environmental, gender or economic efficiency concerns) continues to proliferate. These instruments represent important components of contemporary political governance and hence are an important locus for applied research. This special issue of Impact Assessment and Project Appraisal critically examines 'state-of-the-art' knowledge and understanding of the effecti...

  6. Evaluating the effectiveness of impact assessment instruments

    DEFF Research Database (Denmark)

    Cashmore, Matthew; Richardson, Tim; Hilding-Ryedvik, Tuija

    2010-01-01

    to sharpen effectiveness evaluation theory for impact assessment instruments this article critically examines the neglected issue of their political constitution. Analytical examples are used to concretely explore the nature and significance of the politicisation of impact assessment. It is argued......The central role of impact assessment instruments globally in policy integration initiatives has been cemented in recent years. Associated with this trend, but also reflecting political emphasis on greater accountability in certain policy sectors and a renewed focus on economic competitiveness...... that raising awareness about the political character of impact assessment instruments, in itself, is a vital step in advancing effectiveness evaluation theory. Broader theoretical lessons on the framing of evaluation research are also drawn from the political analysis. We conclude that, at least within...

  7. Invited Article: Deep Impact instrument calibration

    International Nuclear Information System (INIS)

    Klaasen, Kenneth P.; Mastrodemos, Nickolaos; A'Hearn, Michael F.; Farnham, Tony; Groussin, Olivier; Ipatov, Sergei; Li Jianyang; McLaughlin, Stephanie; Sunshine, Jessica; Wellnitz, Dennis; Baca, Michael; Delamere, Alan; Desnoyer, Mark; Thomas, Peter; Hampton, Donald; Lisse, Carey

    2008-01-01

    Calibration of NASA's Deep Impact spacecraft instruments allows reliable scientific interpretation of the images and spectra returned from comet Tempel 1. Calibrations of the four onboard remote sensing imaging instruments have been performed in the areas of geometric calibration, spatial resolution, spectral resolution, and radiometric response. Error sources such as noise (random, coherent, encoding, data compression), detector readout artifacts, scattered light, and radiation interactions have been quantified. The point spread functions (PSFs) of the medium resolution instrument and its twin impactor targeting sensor are near the theoretical minimum [∼1.7 pixels full width at half maximum (FWHM)]. However, the high resolution instrument camera was found to be out of focus with a PSF FWHM of ∼9 pixels. The charge coupled device (CCD) read noise is ∼1 DN. Electrical cross-talk between the CCD detector quadrants is correctable to <2 DN. The IR spectrometer response nonlinearity is correctable to ∼1%. Spectrometer read noise is ∼2 DN. The variation in zero-exposure signal level with time and spectrometer temperature is not fully characterized; currently corrections are good to ∼10 DN at best. Wavelength mapping onto the detector is known within 1 pixel; spectral lines have a FWHM of ∼2 pixels. About 1% of the IR detector pixels behave badly and remain uncalibrated. The spectrometer exhibits a faint ghost image from reflection off a beamsplitter. Instrument absolute radiometric calibration accuracies were determined generally to <10% using star imaging. Flat-field calibration reduces pixel-to-pixel response differences to ∼0.5% for the cameras and <2% for the spectrometer. A standard calibration image processing pipeline is used to produce archival image files for analysis by researchers.

  8. Invited Article: Deep Impact instrument calibration.

    Science.gov (United States)

    Klaasen, Kenneth P; A'Hearn, Michael F; Baca, Michael; Delamere, Alan; Desnoyer, Mark; Farnham, Tony; Groussin, Olivier; Hampton, Donald; Ipatov, Sergei; Li, Jianyang; Lisse, Carey; Mastrodemos, Nickolaos; McLaughlin, Stephanie; Sunshine, Jessica; Thomas, Peter; Wellnitz, Dennis

    2008-09-01

    Calibration of NASA's Deep Impact spacecraft instruments allows reliable scientific interpretation of the images and spectra returned from comet Tempel 1. Calibrations of the four onboard remote sensing imaging instruments have been performed in the areas of geometric calibration, spatial resolution, spectral resolution, and radiometric response. Error sources such as noise (random, coherent, encoding, data compression), detector readout artifacts, scattered light, and radiation interactions have been quantified. The point spread functions (PSFs) of the medium resolution instrument and its twin impactor targeting sensor are near the theoretical minimum [ approximately 1.7 pixels full width at half maximum (FWHM)]. However, the high resolution instrument camera was found to be out of focus with a PSF FWHM of approximately 9 pixels. The charge coupled device (CCD) read noise is approximately 1 DN. Electrical cross-talk between the CCD detector quadrants is correctable to <2 DN. The IR spectrometer response nonlinearity is correctable to approximately 1%. Spectrometer read noise is approximately 2 DN. The variation in zero-exposure signal level with time and spectrometer temperature is not fully characterized; currently corrections are good to approximately 10 DN at best. Wavelength mapping onto the detector is known within 1 pixel; spectral lines have a FWHM of approximately 2 pixels. About 1% of the IR detector pixels behave badly and remain uncalibrated. The spectrometer exhibits a faint ghost image from reflection off a beamsplitter. Instrument absolute radiometric calibration accuracies were determined generally to <10% using star imaging. Flat-field calibration reduces pixel-to-pixel response differences to approximately 0.5% for the cameras and <2% for the spectrometer. A standard calibration image processing pipeline is used to produce archival image files for analysis by researchers.

  9. Instrumented impact testing machine with reduced specimen oscillation effects

    International Nuclear Information System (INIS)

    Rintamaa, R.; Rahka, K.; Wallin, K.

    1984-07-01

    Owing to small and inexpensive specimens the Charpy impact test is widely used in quality control and alloy development. Limitations in power reactor survellance capsules it is also widely used for safety analysis purposes. Instrumenting the tup and computerizing data acquisition, makes dynamic fracture mechanics data measurement possible and convenient. However, the dynamic effects (inertia forces, specimen oscillations) in the impact test cause inaccuracies in the recorded load-time diagram and hence diminish the reliability of the calculated dynamic fracture mechanics parameters. To decrease inaccuracies a new pendulum type of instrumented impact test apparatus has been developed and constructed in the Metals Laboratory of the Technical Research Centre of Finland. This tester is based on a new principle involving inverted test geometry. The purpose of the geometry inversion is to reduce inertia load and specimen oscillation effects. Further, the new impact tester has some other novel features: e.g. the available initia impact energy is about double compared to the conventional standard (300 J) impact tester allowing the use of larger (10 x 20 x 110 mm) bend specimens than normal Charpy specimens. Also, the rotation asix in the three point bending is nearly stationary making COD-measurements possible. An experimental test series is described in which the inertia effects and specimen oscillations are compared in the conventional and new impact tester utilizing Charpy V-notch specimens. Comparison of the two test geometries is also made with the aid of an analytical model using finite element method (FEM) analysis. (author)

  10. Acoustic emission measurement during instrumented impact tests

    International Nuclear Information System (INIS)

    Crostack, H.A.; Engelhardt, A.H.

    1983-01-01

    Results of instrumented impact tests are discussed. On the one hand the development of the loading process at the hammer tup was recorded by means of a piezoelectric transducer. This instrumentation supplied a better representation of the load versus time than the conventional strain gauges. On the other hand the different types of acoustic emission occurring during a test could be separated. The acoustic emission released at the impact of the hammer onto the specimen is of lower frequency and its spectrum is strongly decreasing with increasing frequency. Plastic deformation also emits signals of lower frequency that are of quasi-continuous character. Both signal types can be discriminated by filtering. As a consequence typical burst signal were received afterwards that can be correlated with crack propagation. Their spectra exhibit considerable portions up to about 1.9 MHz. The development in time of the burst signals points to the kind of crack propagation resp. its sequence of appearance. However, definitive comparison between load and acoustic emission should become possible, only when the disadvantages of the common load measurement can be reduced, e.g. by determining the load directly at the specimen instead of the hammer tup

  11. Impact of instrument response variations on health physics measurements

    International Nuclear Information System (INIS)

    Armantrout, G.A.

    1984-10-01

    Uncertainties in estimating the potential health impact of a given radiation exposure include instrument measurement error in determining exposure and difficulty in relating this exposure to an effective dose value. Instrument error can be due to design or manufacturing deficiencies, limitations of the sensing element used, and calibration and maintenance of the instrument. This paper evaluates the errors which can be introduced by design deficiencies and limitations of the sensing element for a wide variety of commonly used survey instruments. The results indicate little difference among sensing element choice for general survey work, with variations among specific instrument designs being the major factor. Ion chamber instruments tend to be the best for all around use, while scintillator-based units should not be used where accurate measurements are required. The need to properly calibrate and maintain an instrument appears to be the most important factor in instrument accuracy. 8 references, 6 tables

  12. [Physician payment mechanisms. An instrument of health policy].

    Science.gov (United States)

    Nigenda, G

    1994-01-01

    Payment mechanisms for physicians have always been subject of debate. The profession tends to prefer fee-for-services, while health care institutions prefer to pay doctors by salary or capitation. The definition of the payment mechanism is not an administrative decision, it is frequently the output of an intense political negotiation. Recently an increase in salaried physicians has been observed, even in countries where the profession is powerful. In nations like Mexico, where the State is the dominant actor, salary or capitation can be used as an instrument to encourage quality of care and better geographic distribution. In this paper, several country cases are reviewed.

  13. Single specimen fracture toughness determination procedure using instrumented impact test

    International Nuclear Information System (INIS)

    Rintamaa, R.

    1993-04-01

    In the study a new single specimen test method and testing facility for evaluating dynamic fracture toughness has been developed. The method is based on the application of a new pendulum type instrumented impact tester equipped with and optical crack mouth opening displacement (COD) extensometer. The fracture toughness measurement technique uses the Double Displacement Ratio (DDR) method, which is based on the assumption that the specimen is deformed as two rigid arms that rotate around an apparent centre of rotation. This apparent moves as the crack grows, and the ratio of COD versus specimen displacement changes. As a consequence the onset ductile crack initiation can be detected on the load-displacement curve. Thus, an energy-based fracture toughness can be calculated. In addition the testing apparatus can use specimens with the Double ligament size as compared with the standard Charpy specimen which makes the impact testing more appropriate from the fracture mechanics point of view. The novel features of the testing facility and the feasibility of the new DDR method has been verified by performing an extensive experimental and analytical study. (99 refs., 91 figs., 27 tabs.)

  14. Mechanical Description of the Mars Climate Sounder Instrument

    Science.gov (United States)

    Jau, Bruno M.

    2008-01-01

    This paper introduces the Mars Climate Sounder (MCS) Instrument of the Mars Reconnaissance Orbiter (MRO) spacecraft. The instrument scans the Martian atmosphere almost continuously to systematically acquire weather and climate observations over time. Its primary components are an optical bench that houses dual telescopes with a total of nine channels for visible and infrared sensing, and a two axis gimbal that provides pointing capabilities. Both rotating joints consist of an integrated actuator with a hybrid planetary/harmonic transmission and a twist cap section that enables the electrical wiring to pass through the rotating joint. Micro stepping is used to reduce spacecraft disturbance torques to acceptable levels while driving the stepper motors. To ensure survivability over its four year life span, suitable mechanical components, lubrication, and an active temperature control system were incorporated. Some life test results and lessons learned are provided to serve as design guidelines for actuator parts and flex cables.

  15. Human-Robot Collaboration Dynamic Impact Testing and Calibration Instrument for Disposable Robot Safety Artifacts.

    Science.gov (United States)

    Dagalakis, Nicholas G; Yoo, Jae Myung; Oeste, Thomas

    2016-01-01

    The Dynamic Impact Testing and Calibration Instrument (DITCI) is a simple instrument with a significant data collection and analysis capability that is used for the testing and calibration of biosimulant human tissue artifacts. These artifacts may be used to measure the severity of injuries caused in the case of a robot impact with a human. In this paper we describe the DITCI adjustable impact and flexible foundation mechanism, which allows the selection of a variety of impact force levels and foundation stiffness. The instrument can accommodate arrays of a variety of sensors and impact tools, simulating both real manufacturing tools and the testing requirements of standards setting organizations. A computer data acquisition system may collect a variety of impact motion, force, and torque data, which are used to develop a variety of mathematical model representations of the artifacts. Finally, we describe the fabrication and testing of human abdomen soft tissue artifacts, used to display the magnitude of impact tissue deformation. Impact tests were performed at various maximum impact force and average pressure levels.

  16. Instrument air system - Aging impact on system availability

    International Nuclear Information System (INIS)

    Villaran, M.; Subudhi, M.

    1989-01-01

    As part of ongoing efforts to understand and manage the effects of aging in nuclear power plants, an aging assessment was performed for the Instrument Air (IA) system, a system that has been the subject of much scrutiny in recent years. Despite its non-safety classification, instrument air has been a factor in a number of potentially serious events. This report presents the results of the assessment and discusses the impact of instrument air system aging on system availability and plant safety. This work was performed for the US Nuclear Regulatory Commission (NRC) as part of the Nuclear Plant Aging Research (NPAR) program. To perform the complex task of analyzing an entire system, the Aging and Life Extension Assessment Program (ALEAP) System Level Plan was developed by Brookhaven National Laboratory and applied successfully in previous system aging studies. The work presented herein was performed using two parallel work paths, as described in the ALEAP plant. One path used deterministic techniques to assess the impact of aging on compressed air system performance, while the second path used probabilistic methods. Results from both paths then were used to characterize aging in the instrument air system. Some conclusions from this work are: compressors, air system valves, and air dryers were found to make up the majority of failures; the effectiveness and quantity of preventive maintenance devoted to a component significantly affected the amount of failures experienced; review of compressed air system designs and studies using a PRA-based system model revealed that the redundancy of key components (compressors, dryers, IA/SA crossconnect valve) was an important factor in system availability; total loss of air events are uncommon

  17. Validation of the force and frequency characteristics of the activator adjusting instrument: effectiveness as a mechanical impedance measurement tool.

    Science.gov (United States)

    Keller, T S; Colloca, C J; Fuhr, A W

    1999-02-01

    To determine the dynamic force-time and force-frequency characteristics of the Activator Adjusting Instrument and to validate its effectiveness as a mechanical impedance measurement device; in addition, to refine or optimize the force-frequency characteristics of the Activator Adjusting Instrument to provide enhanced dynamic structural measurement reliability and accuracy. An idealized test structure consisting of a rectangular steel beam with a static stiffness similar to that of the human thoracolumbar spine was used for validation of a method to determine the dynamic mechanical response of the spine. The Activator Adjusting Instrument equipped with a load cell and accelerometer was used to measure forces and accelerations during mechanical excitation of the steel beam. Driving point and transfer mechanical impedance and resonant frequency of the beam were determined by use of a frequency spectrum analysis for different force settings, stylus masses, and stylus tips. Results were compared with beam theory and transfer impedance measurements obtained by use of a commercial electronic PCB impact hammer. The Activator Adjusting Instrument imparted a very complex dynamic impact comprising an initial high force (116 to 140 N), short duration pulse (analysis of the Activator Adjusting Instrument impulse indicated that the Activator Adjusting Instrument has a variable force spectrum and delivers its peak energy at a frequency of 20 Hz. Added masses and different durometer stylus tips had very little influence on the Activator Adjusting Instrument force spectrum. The resonant frequency of the beam was accurately predicted by both the Activator Adjusting Instrument and electronic PCB impact hammer, but variations in the magnitude of the driving point impedance at the resonant frequency were high (67%) compared with the transfer impedance measurements obtained with the electronic PCB impact hammer, which had a more uniform force spectrum and was more repeatable (frequency

  18. Instrumented Impact Testing: Influence of Machine Variables and Specimen Position

    Energy Technology Data Exchange (ETDEWEB)

    Lucon, E.; McCowan, C. N.; Santoyo, R. A.

    2008-09-15

    An investigation has been conducted on the influence of impact machine variables and specimen positioning on characteristic forces and absorbed energies from instrumented Charpy tests. Brittle and ductile fracture behavior has been investigated by testing NIST reference samples of low, high and super-high energy levels. Test machine variables included tightness of foundation, anvil and striker bolts, and the position of the center of percussion with respect to the center of strike. For specimen positioning, we tested samples which had been moved away or sideways with respect to the anvils. In order to assess the influence of the various factors, we compared mean values in the reference (unaltered) and altered conditions; for machine variables, t-test analyses were also performed in order to evaluate the statistical significance of the observed differences. Our results indicate that the only circumstance which resulted in variations larger than 5 percent for both brittle and ductile specimens is when the sample is not in contact with the anvils. These findings should be taken into account in future revisions of instrumented Charpy test standards.

  19. Instrumented Impact Testing: Influence of Machine Variables and Specimen Position

    International Nuclear Information System (INIS)

    Lucon, E.; McCowan, C. N.; Santoyo, R. A.

    2008-01-01

    An investigation has been conducted on the influence of impact machine variables and specimen positioning on characteristic forces and absorbed energies from instrumented Charpy tests. Brittle and ductile fracture behavior has been investigated by testing NIST reference samples of low, high and super-high energy levels. Test machine variables included tightness of foundation, anvil and striker bolts, and the position of the center of percussion with respect to the center of strike. For specimen positioning, we tested samples which had been moved away or sideways with respect to the anvils. In order to assess the influence of the various factors, we compared mean values in the reference (unaltered) and altered conditions; for machine variables, t-test analyses were also performed in order to evaluate the statistical significance of the observed differences. Our results indicate that the only circumstance which resulted in variations larger than 5 percent for both brittle and ductile specimens is when the sample is not in contact with the anvils. These findings should be taken into account in future revisions of instrumented Charpy test standards.

  20. Instrumentation

    International Nuclear Information System (INIS)

    Prieur, G.; Nadi, M.; Hedjiedj, A.; Weber, S.

    1995-01-01

    This second chapter on instrumentation gives little general consideration on history and classification of instrumentation, and two specific states of the art. The first one concerns NMR (block diagram of instrumentation chain with details on the magnets, gradients, probes, reception unit). The first one concerns precision instrumentation (optical fiber gyro-meter and scanning electron microscope), and its data processing tools (programmability, VXI standard and its history). The chapter ends with future trends on smart sensors and Field Emission Displays. (D.L.). Refs., figs

  1. Instrumentation

    International Nuclear Information System (INIS)

    Decreton, M.

    2000-01-01

    SCK-CEN's research and development programme on instrumentation aims at evaluating the potentials of new instrumentation technologies under the severe constraints of a nuclear application. It focuses on the tolerance of sensors to high radiation doses, including optical fibre sensors, and on the related intelligent data processing needed to cope with the nuclear constraints. Main achievements in these domains in 1999 are summarised

  2. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2001-04-01

    SCK-CEN's research and development programme on instrumentation involves the assessment and the development of sensitive measurement systems used within a radiation environment. Particular emphasis is on the assessment of optical fibre components and their adaptability to radiation environments. The evaluation of ageing processes of instrumentation in fission plants, the development of specific data evaluation strategies to compensate for ageing induced degradation of sensors and cable performance form part of these activities. In 2000, particular emphasis was on in-core reactor instrumentation applied to fusion, accelerator driven and water-cooled fission reactors. This involved the development of high performance instrumentation for irradiation experiments in the BR2 reactor in support of new instrumentation needs for MYRRHA, and for diagnostic systems for the ITER reactor.

  3. Instrumentation

    International Nuclear Information System (INIS)

    Decreton, M.

    2001-01-01

    SCK-CEN's research and development programme on instrumentation involves the assessment and the development of sensitive measurement systems used within a radiation environment. Particular emphasis is on the assessment of optical fibre components and their adaptability to radiation environments. The evaluation of ageing processes of instrumentation in fission plants, the development of specific data evaluation strategies to compensate for ageing induced degradation of sensors and cable performance form part of these activities. In 2000, particular emphasis was on in-core reactor instrumentation applied to fusion, accelerator driven and water-cooled fission reactors. This involved the development of high performance instrumentation for irradiation experiments in the BR2 reactor in support of new instrumentation needs for MYRRHA, and for diagnostic systems for the ITER reactor

  4. Renewable heating: Perspectives and the impact of policy instruments

    International Nuclear Information System (INIS)

    Kranzl, Lukas; Hummel, Marcus; Müller, Andreas; Steinbach, Jan

    2013-01-01

    In the light of the EU directive for renewable energy (2009/28/EC) this paper deals with the question how various policy instruments could impact the development of renewable heating technologies. The paper applies the simulation model Invert/EE-Lab for the building related heat demand in selected European countries (Austria, Lithuania and United Kingdom). The resulting scenarios up to 2030 are compared to RES-Heat targets from literature, stakeholder consultation processes and the targets in the national renewable energy action plans submitted by EU Member States in 2010. The results demonstrate that use obligations for renewable heating can be effective in achieving RES-Heat market growth. However, in order to attain a balanced technology mix and more ambitious targets, policy packages are required combining use obligations with economic incentives and accompanying measures. Technology specific conclusions are derived. Moreover, conclusions indicate that the action plans are not always consistent with policy measures in place or under discussion. - Highlights: • Modeling of RES-Heat policies in the building sector. • Application of the model Invert/EE-Lab for the cases of AT, LT, UK. • RES-Heat use obligations are effective but should be integrated in policy packages. • The design of use obligations has substantial impact on the RES-H technology mix. • National renewable energy action plans are not always consistent with policies

  5. Instrumentation

    International Nuclear Information System (INIS)

    Decreton, M.

    2002-01-01

    SCK-CEN's R and D programme on instrumentation involves the development of advanced instrumentation systems for nuclear applications as well as the assessment of the performance of these instruments in a radiation environment. Particular emphasis is on the use of optical fibres as umbilincal links of a remote handling unit for use during maintanance of a fusion reacor, studies on the radiation hardening of plasma diagnostic systems; investigations on new instrumentation for the future MYRRHA accelerator driven system; space applications related to radiation-hardened lenses; the development of new approaches for dose, temperature and strain measurements; the assessment of radiation-hardened sensors and motors for remote handling tasks and studies of dose measurement systems including the use of optical fibres. Progress and achievements in these areas for 2001 are described

  6. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2002-04-01

    SCK-CEN's R and D programme on instrumentation involves the development of advanced instrumentation systems for nuclear applications as well as the assessment of the performance of these instruments in a radiation environment. Particular emphasis is on the use of optical fibres as umbilincal links of a remote handling unit for use during maintanance of a fusion reacor, studies on the radiation hardening of plasma diagnostic systems; investigations on new instrumentation for the future MYRRHA accelerator driven system; space applications related to radiation-hardened lenses; the development of new approaches for dose, temperature and strain measurements; the assessment of radiation-hardened sensors and motors for remote handling tasks and studies of dose measurement systems including the use of optical fibres. Progress and achievements in these areas for 2001 are described.

  7. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2000-07-01

    SCK-CEN's research and development programme on instrumentation aims at evaluating the potentials of new instrumentation technologies under the severe constraints of a nuclear application. It focuses on the tolerance of sensors to high radiation doses, including optical fibre sensors, and on the related intelligent data processing needed to cope with the nuclear constraints. Main achievements in these domains in 1999 are summarised.

  8. Laboratory comparison of the mechanical properties of TRUShape with several nickel-titanium rotary instruments.

    Science.gov (United States)

    Elnaghy, A M; Elsaka, S E

    2017-08-01

    To assess and compare the mechanical properties of TRUShape (TRS) with several nickel-titanium rotary instruments. Cyclic fatigue, torsional resistance, flexibility and surface microhardness of TRS (size 25, 0.06v taper), ProTaper Next X2 (PTN X2, size 25, 0.06 taper), ProTaper Gold (PTG F2; size 25, 0.08 taper) and ProTaper Universal (PTU F2; size 25, 0.08 taper) instruments were evaluated. The topographical structures of the fracture surfaces of instruments were assessed using a scanning electron microscope. The cyclic fatigue resistance, torsional resistance and microhardness data were analysed using one-way analysis of variance (anova) and Tukey's post hoc tests. The fragment length and bending resistance data were analysed statistically with the Kruskal-Wallis H-test and Mann-Whitney U-tests. The statistical significance level was set at P instruments revealed significantly higher resistance to cyclic fatigue than TRS and PTU instruments (P instruments revealed significantly higher torsional resistance compared with the other instruments (P instrument had significantly higher flexibility than the other tested brands (P instruments had lower resistance to cyclic fatigue and lower flexibility compared with PTG and PTN instruments. TRS, PTG and PTU instruments had lower resistance to torsional stress than PTN instruments. TRS and PTG instruments had comparable surface microhardness. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  9. Focal plane mechanical design of the NISP/Euclid instrument

    Science.gov (United States)

    Bonnefoi, Anne; Bon, William; Niclas, Mathieu; Solheim, Bjarte G. B.; Torvanger, Oyvind; Schistad, Robert; Foulon, Benjamin; Garcia, José; Vives, Sébastien

    2016-07-01

    Currently in phase C, the Euclid mission selected by ESA in the Cosmic Vision program is dedicated to understand dark energy and dark matter. NISP (standing for Near Infrared Spectro-Photometer) is one of the two instruments of the mission. NISP will combine a photometer and a spectrometer working in the near-IR (0.9-2 microns). Its detection subsystem (called NI-DS) is based on a mosaic of 16 IR detectors cooled down to 90K which are supported by a molybdenum plate. The front-end readout electronics (working at 130K) are supported by another structure in Aluminum. The NI-DS is mounted on the rest of the instrument thanks to a panel in Silicon Carbide (SiC). Finally an optical baffle in Titanium will prevent the rogue light to reach the detectors. On top of the complexity due to the wide range of temperatures and the various materials imposed at the interfaces; the NI-DS has also to incorporate an internal adjustment capability of the position of the focal plane in tip/tilt and focus. This article will present current status of the development of the detection system of NISP.

  10. Instrumentation

    International Nuclear Information System (INIS)

    Umminger, K.

    2008-01-01

    A proper measurement of the relevant single and two-phase flow parameters is the basis for the understanding of many complex thermal-hydraulic processes. Reliable instrumentation is therefore necessary for the interaction between analysis and experiment especially in the field of nuclear safety research where postulated accident scenarios have to be simulated in experimental facilities and predicted by complex computer code systems. The so-called conventional instrumentation for the measurement of e. g. pressures, temperatures, pressure differences and single phase flow velocities is still a solid basis for the investigation and interpretation of many phenomena and especially for the understanding of the overall system behavior. Measurement data from such instrumentation still serves in many cases as a database for thermal-hydraulic system codes. However some special instrumentation such as online concentration measurement for boric acid in the water phase or for non-condensibles in steam atmosphere as well as flow visualization techniques were further developed and successfully applied during the recent years. Concerning the modeling needs for advanced thermal-hydraulic codes, significant advances have been accomplished in the last few years in the local instrumentation technology for two-phase flow by the application of new sensor techniques, optical or beam methods and electronic technology. This paper will give insight into the current state of instrumentation technology for safety-related thermohydraulic experiments. Advantages and limitations of some measurement processes and systems will be indicated as well as trends and possibilities for further development. Aspects of instrumentation in operating reactors will also be mentioned.

  11. A mechanical impact of coatings on membranes

    DEFF Research Database (Denmark)

    Hansen, Michael Søren; Reus, Roger De; Eriksen, Gert Friis

    2001-01-01

    The mechanical impact of coatings containing residual stress on membranes is investigated. Closed-form formulas describing this impact are presented and verified using both finite element modeling and physical experiments. Theory and experiments are in good agreement. Thus, a simple tool for design...... of coated pressure sensors is provided....

  12. Instruments

    International Nuclear Information System (INIS)

    Buehrer, W.

    1996-01-01

    The present paper mediates a basic knowledge of the most commonly used experimental techniques. We discuss the principles and concepts necessary to understand what one is doing if one performs an experiment on a certain instrument. (author) 29 figs., 1 tab., refs

  13. Mechanical processes with repeated attenuated impacts

    CERN Document Server

    Nagaev, R F

    1999-01-01

    This book is devoted to considering in the general case - using typical concrete examples - the motion of machines and mechanisms of impact and vibro-impact action accompanied by a peculiar phenomenon called "impact collapse". This phenomenon is that after the initial collision, a sequence of repeated gradually quickening collisions of decreasing-to-zero intensity occurs, with the final establishment of protracted contact between the interacting bodies. The initiation conditions of the impact collapse are determined and calculation techniques for the quantitative characteristics of the corresp

  14. Mechanical and Metallurgical Properties of Various Nickel-Titanium Rotary Instruments

    Directory of Open Access Journals (Sweden)

    Kyu-Sang Shim

    2017-01-01

    Full Text Available The aim of this study was to investigate the effect of thermomechanical treatment on mechanical and metallurgical properties of nickel-titanium (NiTi rotary instruments. Eight kinds of NiTi rotary instruments with sizes of ISO #25 were selected: ProFile, K3, and One Shape for the conventional alloy; ProTaper NEXT, Reciproc, and WaveOne for the M-wire alloy; HyFlex CM for the controlled memory- (CM- wire; and TF for the R-phase alloy. Torsional fracture and cyclic fatigue fracture tests were performed. Products underwent a differential scanning calorimetry (DSC analysis. The CM-wire and R-phase groups had the lowest elastic modulus, followed by the M-wire group. The maximum torque of the M-wire instrument was comparable to that of a conventional instrument, while those of the CM-wire and R-phase instruments were lower. The angular displacement at failure (ADF for the CM-wire and R-phase instruments was higher than that of conventional instruments, and ADF of the M-wire instruments was lower. The cyclic fatigue resistance of the thermomechanically treated NiTi instruments was higher. DSC plots revealed that NiTi instruments made with the conventional alloy were primarily composed of austenite at room temperature; stable martensite and R-phase were found in thermomechanically treated instruments.

  15. The mechanical design and dynamic testing of the IBEX-H1 electrostatic analyzer spacecraft instrument

    Energy Technology Data Exchange (ETDEWEB)

    Bernardin, John D [Los Alamos National Laboratory; Baca, Allen G [SNL

    2009-01-01

    This paper presents the mechanical design, fabrication and dynamic testing of an electrostatic analyzer spacecraft instrument. The functional and environmental requirements combined with limited spacecraft accommodations, resulted in complex component geometries, unique material selections, and difficult fabrication processes. The challenging aspects of the mechanical design and several of the more difficult production processes are discussed. In addition, the successes, failures, and lessons learned from acoustic and random vibration testing of a full-scale prototype instrument are presented.

  16. EURATOM, the year 2000 and its impact on the reporting system and instrumentation

    International Nuclear Information System (INIS)

    Chare, P.J.

    1999-01-01

    Presentation includes the Y2K potential problem areas, its impact on the reporting system and instrumentation as well as achievements done so far. The potential problem areas are: reporting system, headquarters system, installed instrumentation and stand alone instrumentation. A complete list of EURATOM equipment is listed. Specific problem areas concerned include data acquisition programmes. Reporting system is Y2K compatible, headquarters systems will be after upgrading, problems concerning instrumentation are identified and will be upgraded in 1999

  17. Instrumentation

    International Nuclear Information System (INIS)

    Muehllehner, G.; Colsher, J.G.

    1982-01-01

    This chapter reviews the parameters which are important to positron-imaging instruments. It summarizes the options which various groups have explored in designing tomographs and the methods which have been developed to overcome some of the limitations inherent in the technique as well as in present instruments. The chapter is not presented as a defense of positron imaging versus single-photon or other imaging modality, neither does it contain a description of various existing instruments, but rather stresses their common properties and problems. Design parameters which are considered are resolution, sampling requirements, sensitivity, methods of eliminating scattered radiation, random coincidences and attenuation. The implementation of these parameters is considered, with special reference to sampling, choice of detector material, detector ring diameter and shielding and variations in point spread function. Quantitation problems discussed are normalization, and attenuation and random corrections. Present developments mentioned are noise reduction through time-of-flight-assisted tomography and signal to noise improvements through high intrinsic resolution. Extensive bibliography. (U.K.)

  18. Opto-mechanical design for transmission optics in cryogenic space instrumentation

    Science.gov (United States)

    Kroes, Gabby; Venema, Lars; Navarro, Ramón

    2017-11-01

    NOVA is involved in the development and realization of various optical astronomical instruments for groundbased as well as space telescopes, with a focus on nearand mid-infrared instrumentation. NOVA has developed a suite of scientific instruments with cryogenic optics for the ESO VLT and VLTI instruments: VISIR, MIDI, the SPIFFI 2Kcamera for SINFONI, X-shooter and MATISSE. Other projects include the cryogenic optics for MIRI for the James Webb Space Telescope and several E-ELT instruments. Mounting optics is always a compromise between firmly fixing the optics and preventing stresses within the optics. The fixing should ensure mechanical stability and thus accurate positioning in various gravity orientations, temperature ranges, during launch, transport or earthquake. On the other hand, the fixings can induce deformations and sometimes birefringence in the optics and thus cause optical errors. Even cracking or breaking of the optics is a risk, especially when using brittle infrared optical materials at the cryogenic temperatures required in instruments for infrared astronomy, where differential expansion of various materials amounts easily to several millimeters per meter. Special kinematic mounts are therefore needed to ensure both accurate positioning and low stress. This paper concentrates on the opto-mechanical design of optics mountings, especially for large transmission optics in cryogenic circumstances in space instruments. It describes the development of temperature-invariant ("a-thermal") kinematic designs, their implementation in ground based instrumentation and ways to make them suitable for space instruments.

  19. Impact of Smoke Exposure on Digital Instrumentation and Control

    International Nuclear Information System (INIS)

    Tanaka, Tina J.; Nowlen, Steven P.; Korsah, Kofi; Wood, Richard T.; Antonescu, Christina E.

    2003-01-01

    Smoke can cause interruptions and upsets in active electronics. Because nuclear power plants are replacing analog with digital instrumentation and control systems, qualification guidelines for new systems are being reviewed for severe environments such as smoke and electromagnetic interference. Active digital systems, individual components, and active circuits have been exposed to smoke in a program sponsored by the U.S. Nuclear Regulatory Commission. The circuits and systems were all monitored during the smoke exposure, indicating any immediate effects of the smoke. The results of previous smoke exposure studies have been reported in various publications. The major immediate effect of smoke has been to increase leakage currents and to cause momentary upsets and failures in digital systems. This paper presents new results from conformal coatings, memory chips, and hard drive tests.The best conformal coatings were found to be polyurethane, parylene, and acrylic (when applied by dipping). Conformal coatings can reduce smoke-induced leakage currents and protect against metal loss through corrosion. However conformal coatings are typically flammable, so they do increase material flammability. Some of the low-voltage biased memory chips failed during a combination of high smoke and high humidity. Typically, smoke along with heat and humidity is expected during fire, rather than smoke alone. Thus, due to high sensitivity of digital circuits to heat and humidity, it is hypothesized that the impact of smoke may be secondary.Low-voltage (3.3-V) static random-access memory (SRAMs) were found to be the most vulnerable to smoke. Higher bias voltages decrease the likelihood of failure. Erasable programmable read-only memory (EPROMs) and nonvolatile SRAMs were very smoke tolerant. Failures of the SRAMs occurred when two conditions were present: high density of smoke and high humidity. As the high humidity was present for only part of the test, the failures were intermittent. All

  20. Assessing learning outcomes in middle-division classical mechanics: The Colorado Classical Mechanics and Math Methods Instrument

    Science.gov (United States)

    Caballero, Marcos D.; Doughty, Leanne; Turnbull, Anna M.; Pepper, Rachel E.; Pollock, Steven J.

    2017-06-01

    Reliable and validated assessments of introductory physics have been instrumental in driving curricular and pedagogical reforms that lead to improved student learning. As part of an effort to systematically improve our sophomore-level classical mechanics and math methods course (CM 1) at CU Boulder, we have developed a tool to assess student learning of CM 1 concepts in the upper division. The Colorado Classical Mechanics and Math Methods Instrument (CCMI) builds on faculty consensus learning goals and systematic observations of student difficulties. The result is a 9-question open-ended post test that probes student learning in the first half of a two-semester classical mechanics and math methods sequence. In this paper, we describe the design and development of this instrument, its validation, and measurements made in classes at CU Boulder and elsewhere.

  1. Assessing learning outcomes in middle-division classical mechanics: The Colorado Classical Mechanics and Math Methods Instrument

    Directory of Open Access Journals (Sweden)

    Marcos D. Caballero

    2017-04-01

    Full Text Available Reliable and validated assessments of introductory physics have been instrumental in driving curricular and pedagogical reforms that lead to improved student learning. As part of an effort to systematically improve our sophomore-level classical mechanics and math methods course (CM 1 at CU Boulder, we have developed a tool to assess student learning of CM 1 concepts in the upper division. The Colorado Classical Mechanics and Math Methods Instrument (CCMI builds on faculty consensus learning goals and systematic observations of student difficulties. The result is a 9-question open-ended post test that probes student learning in the first half of a two-semester classical mechanics and math methods sequence. In this paper, we describe the design and development of this instrument, its validation, and measurements made in classes at CU Boulder and elsewhere.

  2. The mechanics of ship impacts against bridges

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    a glancing blow between the ship and the bridge structure. This model is based on rigid body mechanics and well suited for inclusion in a probabilistic analysis procedure. Finally, some empirical expressions are presented which relate the energy absorbed by crushing of ship structures to the maximum impact...

  3. In vitro comparative study of manual and mechanical rotary instrumentation of root canals using computed tomography.

    Science.gov (United States)

    Limongi, Orlando; de Albuquerque, Diana Santana; Baratto Filho, Flares; Vanni, José Roberto; de Oliveira, Elias P Motcy; Barletta, Fernando Branco

    2007-01-01

    This in vitro study compared, using computed tomography (CT), the amount of dentin removed from root canal walls by manual and mechanical rotary instrumentation techniques. Forty mandibular incisors with dental crown and a single canal were selected. The teeth were randomly assigned to two groups, according to the technique used for root canal preparation: Group I - manual instrumentation with stainless steel files; Group II - mechanical instrumentation with RaCe rotary nickel-titanium instruments. In each tooth, root dentin thickness of the buccal, lingual, mesial and distal surfaces in the apical, middle and cervical thirds of the canal was measured (in mm) using a multislice CT scanner (Siemens Emotion, Duo). Data were stored in the SPSS v. 11.5 and SigmaPlot 2001 v. 7.101 softwares. After crown opening, working length was determined, root canals were instrumented and new CT scans were taken for assessment of root dentin thickness. Pre- and post-instrumentation data were compared and analyzed statistically by ANOVA and Tukey's post-hoc test for significant differences (p=0.05). Based on the findings of this study, it may be concluded that regarding dentin removal from root canal walls during instrumentation, neither of the techniques can be considered more effective than the other.

  4. Global and Regional Impacts of the Clean Development Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shunli; De Groot, H.L.F.; Nijkamp, P.; Verhoef, E.T. [VU University, Amsterdam (Netherlands)

    2009-05-15

    Climate change is a serious concern worldwide. Policy research on climate change in the past decades has largely focused on applied modelling exercises. However, the implications of specific policy strategies such as the clean development mechanism (CDM) for global and regional economic and environmental developments has received relatively little attention. This is partly caused by the complexities of modelling an instrument like CDM. By using and modifying the GTAP-E modelling system (GTAP stands for Global Trade Analysis Project), this paper sets out to trace the combined economic and environmental impacts of CDM policies. Particular emphasis is placed on technology transfer induced by alternative CDM policies. Specific attention is devoted to the possible negative consequences of non-participation of the USA in the global coalition, and the associated distributional impacts world-wide.

  5. Global and Regional Impacts of the Clean Development Mechanism

    International Nuclear Information System (INIS)

    Wang, Shunli; De Groot, H.L.F.; Nijkamp, P.; Verhoef, E.T.

    2009-05-01

    Climate change is a serious concern worldwide. Policy research on climate change in the past decades has largely focused on applied modelling exercises. However, the implications of specific policy strategies such as the clean development mechanism (CDM) for global and regional economic and environmental developments has received relatively little attention. This is partly caused by the complexities of modelling an instrument like CDM. By using and modifying the GTAP-E modelling system (GTAP stands for Global Trade Analysis Project), this paper sets out to trace the combined economic and environmental impacts of CDM policies. Particular emphasis is placed on technology transfer induced by alternative CDM policies. Specific attention is devoted to the possible negative consequences of non-participation of the USA in the global coalition, and the associated distributional impacts world-wide.

  6. The Impact of Instrumental Music Learning on Attainment at Age 16: A Pilot Study

    Science.gov (United States)

    Hallam, Susan; Rogers, Kevin

    2016-01-01

    There is increasing international evidence that playing a musical instrument has a positive impact on attainment at school but little research has been undertaken in the UK. This study addresses this drawing on data on attainment at age 11 and 16 relating to 608 students, 115 of whom played a musical instrument. The fndings showed that the young…

  7. Psychometric Evaluation of an Adolescent and Young Adult Module of the Impact of Cancer Instrument

    NARCIS (Netherlands)

    Husson, O.; Zebrack, B.J.

    2017-01-01

    PURPOSE: To develop and evaluate a new instrument that measures unique aspects of long-term survivorship for people diagnosed with cancer as Adolescent and Young Adult (AYA), not measured by existing tools. METHODS: A new candidate instrument-the Impact of Cancer for Adolescent and Young Adult

  8. Investigation of irradiation embrittlement and annealing behaviour of JRQ pressure vessel steel by instrumented impact tests

    Energy Technology Data Exchange (ETDEWEB)

    Valo, M; Rintamaa, R; Nevalainen, M; Wallin, K; Torronen, K [Technical Research Centre of Finland, Espoo (Finland); Tipping, P [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1994-12-31

    Seven series of A533-B type pressure vessel steel specimens irradiated as well as irradiated - annealed - re-irradiated to different fast neutron fluences (up to 5.10{sup 19}/cm{sup 2}) have been tested with a new type of instrumented impact test machine. The radiation embrittlement and the effect of the intermediate annealing was assessed by using the ductile and cleavage fracture initiation toughness. Although the ductile fracture initiation toughness exhibited scatter, the transition temperature shift corresponding to the dynamic cleavage fracture initiation agreed well with the 41 J Charpy-V shift. The results indicate that annealing is beneficial in restoring mechanical properties in an irradiated nuclear pressure vessel steel. (authors). 8 refs., 11 figs., 1 tab.

  9. TRANSMISSION OF IMPACTS DURING MECHANICAL GRAPE HARVESTING AND TRANSPORTATION

    Directory of Open Access Journals (Sweden)

    Fabio Pezzi

    2008-09-01

    Full Text Available The aim of the research was to study vibrational stress on grapes during mechanical harvesting, transfer and delivery to the winery, in order to identify the most critical stages and the consequent effects on the winemaking. An instrumented sphere was used to evaluate and memorise the impacts in the grape harvester and means of transport. Three treatments, obtained by differing harvesting method (manual and mechanical and transport type (short and long distance, were compared. A correlation was sought between the transmitted stresses and characteristics of the harvested product. The effects on product quality were evaluated by chemical analyses of the musts and sensorial analysis of the end-product, vinified using the same procedure.

  10. The Friedrich-Lively Instrument to Assess the Impact of Schizophrenia on Siblings (FLIISS): Part I--instrument construction.

    Science.gov (United States)

    Friedrich, Rose Marie; Lively, Sonja; Rubenstein, Linda; Buckwalter, Kathleen

    2002-01-01

    Siblings of persons with schizophrenia may provide primary or secondary care for their sibling and support to parents who are primary care givers. These siblings experience stress and the accompanying sequelae of decreased quality of life, grief, chronic illness, and symptoms of depression and anxiety. Comprehensive measures of sibling stress have not been published. Before interventions to help siblings can be created, health professionals need such an assessment. The Friedrich-Lively Instrument to Assess the Impact of Schizophrenia on Siblings (FLIISS) has been developed to meet the needs of both health workers and siblings. The instrument has a strong conceptual basis adapted from Pearlin's model of stress in caregiving and was preceded by pilot work that evaluated both quantitative and qualitative data. In this article, (Part I), the development of the instrument and its relationships to the conceptual model are described. Health professionals can use the instrument for collecting information that will increase their ability to identify sources of stress faced by siblings of persons with schizophrenia, and from this assessment they may develop interventions for this underserved population.

  11. New instrument for tribocharge measurement due to single particle impacts

    International Nuclear Information System (INIS)

    Watanabe, Hideo; Ghadiri, Mojtaba; Matsuyama, Tatsushi; Ding Yulong; Pitt, Kendal G.

    2007-01-01

    During particulate solid processing, particle-particle and particle-wall collisions can generate electrostatic charges. This may lead to a variety of problems ranging from fire and explosion hazards to segregation, caking, and blocking. A fundamental understanding of the particle charging in such situations is therefore essential. For this purpose we have developed a new device that can measure charge transfer due to impact between a single particle and a metal plate. The device consists of an impact test system and two sets of Faraday cage and preamplifier for charge measurement. With current amplifiers, high-resolution measurements of particle charges of approximately 1 and 10 fC have been achieved before and after the impact, respectively. The device allows charge measurements of single particles with a size as small as ∼100 μm impacting on the target at different incident angles with a velocity up to about 80 m/s. Further analyses of the charge transfer as a function of particle initial charge define an equilibrium charge, i.e., an initial charge level prior to impact for which no net charge transfer would occur as a result of impact

  12. Nonbinding Legal Instruments in Governance for Global Health: Lessons from the Global AIDS Reporting Mechanism.

    Science.gov (United States)

    Taylor, Allyn; Alfvén, Tobias; Hougendobler, Daniel; Buse, Kent

    2014-01-01

    Recent debate over World Health Organization reform has included unprecedented attention to international lawmaking as a future priority function of the Organization. However, the debate is largely focused on the codification of new binding legal instruments. Drawing upon lessons from the success of the Global AIDS Reporting Mechanism, established pursuant to the United Nations' Declaration of Commitment on HIV/AIDS, we argue that effective global health governance requires consideration of a broad range of instruments, both binding and nonbinding. A detailed examination of the Global AIDS Reporting Mechanism reveals that the choice of the nonbinding format makes an important contribution to its effectiveness. For instance, the flexibility and adaptability of the nonbinding format have allowed the global community to: (1) undertake commitments in a timely manner; (2) adapt and experiment in the face of a dynamic pandemic; and (3) grant civil society an unparalleled role in monitoring and reporting on state implementation of global commitments. UNAIDS' institutional support has also played a vital role in ensuring the continuing effectiveness of the Global AIDS Reporting Mechanism. Overall, the experience of the Global AIDS Reporting Mechanism evidences that, at times, nimbler nonbinding instruments can offer benefits over slower, more rigid binding legal approaches to governance, but depend critically, like all instruments, on the perceived legitimacy thereof. © 2014 American Society of Law, Medicine & Ethics, Inc.

  13. A new device to test cutting efficiency of mechanical endodontic instruments

    Science.gov (United States)

    Rubini, Alessio Giansiracusa; Plotino, Gianluca; Al-Sudani, Dina; Grande, Nicola M.; Putorti, Ermanno; Sonnino, GianPaolo; Cotti, Elisabetta; Testarelli, Luca; Gambarini, Gianluca

    2014-01-01

    Background The purpose of the present study was to introduce a new device specifically designed to evaluate the cutting efficiency of mechanically driven endodontic instruments. Material/Methods Twenty new Reciproc R25 (VDW, Munich, Germany) files were used to be investigated in the new device developed to test the cutting ability of endodontic instruments. The device consists of a main frame to which a mobile plastic support for the hand-piece is connected and a stainless-steel block containing a Plexiglas block against which the cutting efficiency of the instruments was tested. The length of the block cut in 1 minute was measured in a computerized program with a precision of 0.1mm. The instruments were activated by using a torque-controlled motor (Silver Reciproc; VDW, Munich, Germany) in a reciprocating movement by the “Reciproc ALL” program (Group 1) and in counter-clockwise rotation at 300 rpm (Group 2). Mean and standard deviations of each group were calculated and data were statistically analyzed with a one-way ANOVA test (P0.05). Conclusions The cutting testing device evaluated in the present study was reliable and easy to use and may be effectively used to test cutting efficiency of both rotary and reciprocating mechanical endodontic instruments. PMID:24603777

  14. Development and validation of an achievement test in introductory quantum mechanics: The Quantum Mechanics Visualization Instrument (QMVI)

    Science.gov (United States)

    Cataloglu, Erdat

    The purpose of this study was to construct a valid and reliable multiple-choice achievement test to assess students' understanding of core concepts of introductory quantum mechanics. Development of the Quantum Mechanics Visualization Instrument (QMVI) occurred across four successive semesters in 1999--2001. During this time 213 undergraduate and graduate students attending the Pennsylvania State University (PSU) at University Park and Arizona State University (ASU) participated in this development and validation study. Participating students were enrolled in four distinct groups of courses: Modern Physics, Undergraduate Quantum Mechanics, Graduate Quantum Mechanics, and Chemistry Quantum Mechanics. Expert panels of professors of physics experienced in teaching quantum mechanics courses and graduate students in physics and science education established the core content and assisted in the validating of successive versions of the 24-question QMVI. Instrument development was guided by procedures outlined in the Standards for Educational and Psychological Testing (AERA-APA-NCME, 1999). Data gathered in this study provided information used in the development of successive versions of the QMVI. Data gathered in the final phase of administration of the QMVI also provided evidence that the intended score interpretation of the QMVI achievement test is valid and reliable. A moderate positive correlation coefficient of 0.49 was observed between the students' QMVI scores and their confidence levels. Analyses of variance indicated that students' scores in Graduate Quantum Mechanics and Undergraduate Quantum Mechanics courses were significantly higher than the mean scores of students in Modern Physics and Chemistry Quantum Mechanics courses (p important factor for students in acquiring a successful understanding of quantum mechanics.

  15. Mechanisms of Deformation and Fracture of Thin Coatings on Different Substrates in Instrumented Indentation

    Science.gov (United States)

    Eremina, G. M.; Smolin, A. Yu.; Psakhie, S. G.

    2018-04-01

    Mechanical properties of thin surface layers and coatings are commonly studied using instrumented indentation and scratch testing, where the mechanical response of the coating - substrate system essentially depends on the substrate material. It is quite difficult to distinguish this dependence and take it into account in the course of full-scale experiments due to a multivariative and nonlinear character of the influence. In this study the process of instrumented indentation of a hardening coating formed on different substrates is investigated numerically by the method of movable cellular automata. As a result of modeling, we identified the features of the substrate material influence on the derived mechanical characteristics of the coating - substrate systems and the processes of their deformation and fracture.

  16. A mathematical model for describing the mechanical behaviour of root canal instruments.

    Science.gov (United States)

    Zhang, E W; Cheung, G S P; Zheng, Y F

    2011-01-01

    The purpose of this study was to establish a general mathematical model for describing the mechanical behaviour of root canal instruments by combining a theoretical analytical approach with a numerical finite-element method. Mathematical formulas representing the longitudinal (taper, helical angle and pitch) and cross-sectional configurations and area, the bending and torsional inertia, the curvature of the boundary point and the (geometry of) loading condition were derived. Torsional and bending stresses and the resultant deformation were expressed mathematically as a function of these geometric parameters, modulus of elasticity of the material and the applied load. As illustrations, three brands of NiTi endodontic files of different cross-sectional configurations (ProTaper, Hero 642, and Mani NRT) were analysed under pure torsion and pure bending situation by entering the model into a finite-element analysis package (ANSYS). Numerical results confirmed that mathematical models were a feasible method to analyse the mechanical properties and predict the stress and deformation for root canal instruments during root canal preparation. Mathematical and numerical model can be a suitable way to examine mechanical behaviours as a criterion of the instrument design and to predict the stress and strain experienced by the endodontic instruments during root canal preparation. © 2010 International Endodontic Journal.

  17. Mechanical and Metallurgical Properties of Various Nickel-Titanium Rotary Instruments

    OpenAIRE

    Shim, Kyu-Sang; Oh, Soram; Kum, KeeYeon; Kim, Yu-Chan; Jee, Kwang-Koo; Chang, Seok Woo

    2017-01-01

    The aim of this study was to investigate the effect of thermomechanical treatment on mechanical and metallurgical properties of nickel-titanium (NiTi) rotary instruments. Eight kinds of NiTi rotary instruments with sizes of ISO #25 were selected: ProFile, K3, and One Shape for the conventional alloy; ProTaper NEXT, Reciproc, and WaveOne for the M-wire alloy; HyFlex CM for the controlled memory- (CM-) wire; and TF for the R-phase alloy. Torsional fracture and cyclic fatigue fracture tests were...

  18. Wind galleries: an instrument for environmental impact assessment

    International Nuclear Information System (INIS)

    Zunino, C.

    1998-01-01

    In the last decades wind galleries for non-aeronautic utilisation have proved to be a useful investigation tool in various fields, such as studies on environmental impact and risk assessment, associated with permanent or incidental release of harmful substances. In this framework the feasibility of a new installation has been evaluated in Italy, having as main target the reproduction of thermal stratification phenomena. The great deal of 'hazardous' industries, often in areas having a complex orography, as well as the high pollution levels in Italian cities, lead to the conclusion that a thermally stratified wind gallery might be an economically viable investment [it

  19. Development of Mechanical Sealing and Laser Welding Technology to Instrument Thermocouple for Nuclear Fuel Test Rod

    International Nuclear Information System (INIS)

    Joung, Chang-Young; Ahn, Sung-Ho; Hong, Jin-Tae; Kim, Ka-Hye; Huh, Sung-Ho

    2015-01-01

    Zircaloy-4 of the nuclear fuel test rod, AISI 316L of the mechanical sealing parts, and the MI (mineral insulated) cable at a thermocouple instrumentation are hetero-metals, and are difficult to weld to dissimilar materials. Therefore, a mechanical sealing method to instrument the thermocouple should be conducted using two kinds of sealing process as follows: One is a mechanical sealing process using Swagelok, which is composed of sealing components that consists of an end-cap, a seal tube, a compression ring and a Swagelok nut. The other is a laser welding process used to join a seal tube, and an MI cable, which are made of the same material. The mechanical sealing process should be sealed up with the mechanical contact compressed by the strength forced between a seal tube and an end-cap, and the laser welding process should be conducted to have no defects on the sealing area between a seal tube and an MI cable. Therefore, the mechanical sealing and laser welding techniques need to be developed to accurately measure the centerline temperature of the nuclear fuel test rod in an experimental reactor. The mechanical sealing and laser welding tests were conducted to develop the thermocouple instrumentation techniques for the nuclear fuel test rod. The optimum torque value of a Swagelok nut to seal the mechanical sealing part between the end-cap and seal tube was established through various torque tests using a torque wrench. The optimum laser welding conditions to seal the welding part between a seal tube and an MI cable were obtained through various welding tests using a laser welding system

  20. Development of Mechanical Sealing and Laser Welding Technology to Instrument Thermocouple for Nuclear Fuel Test Rod

    Energy Technology Data Exchange (ETDEWEB)

    Joung, Chang-Young; Ahn, Sung-Ho; Hong, Jin-Tae; Kim, Ka-Hye; Huh, Sung-Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Zircaloy-4 of the nuclear fuel test rod, AISI 316L of the mechanical sealing parts, and the MI (mineral insulated) cable at a thermocouple instrumentation are hetero-metals, and are difficult to weld to dissimilar materials. Therefore, a mechanical sealing method to instrument the thermocouple should be conducted using two kinds of sealing process as follows: One is a mechanical sealing process using Swagelok, which is composed of sealing components that consists of an end-cap, a seal tube, a compression ring and a Swagelok nut. The other is a laser welding process used to join a seal tube, and an MI cable, which are made of the same material. The mechanical sealing process should be sealed up with the mechanical contact compressed by the strength forced between a seal tube and an end-cap, and the laser welding process should be conducted to have no defects on the sealing area between a seal tube and an MI cable. Therefore, the mechanical sealing and laser welding techniques need to be developed to accurately measure the centerline temperature of the nuclear fuel test rod in an experimental reactor. The mechanical sealing and laser welding tests were conducted to develop the thermocouple instrumentation techniques for the nuclear fuel test rod. The optimum torque value of a Swagelok nut to seal the mechanical sealing part between the end-cap and seal tube was established through various torque tests using a torque wrench. The optimum laser welding conditions to seal the welding part between a seal tube and an MI cable were obtained through various welding tests using a laser welding system.

  1. Research on seamless development of surgical instruments based on biological mechanisms using CAD and 3D printer.

    Science.gov (United States)

    Yamamoto, Ikuo; Ota, Ren; Zhu, Rui; Lawn, Murray; Ishimatsu, Takakazu; Nagayasu, Takeshi; Yamasaki, Naoya; Takagi, Katsunori; Koji, Takehiko

    2015-01-01

    In the area of manufacturing surgical instruments, the ability to rapidly design, prototype and test surgical instruments is critical. This paper provides a simple case study of the rapid development of two bio-mechanism based surgical instruments which are ergonomic, aesthetic and were successfully designed, prototyped and conceptually tested in a very short period of time.

  2. Mechanical behavior of an instrumented shotcrete drifts definitive lining in a 500 m deep clay formation

    International Nuclear Information System (INIS)

    Zghondi, Jad; Armand, Gilles; Noiret, Aurelien

    2012-01-01

    Document available in extended abstract form only. At the Meuse/Haute Marne Underground Research Laboratory (URL), Andra has developed a technical and scientific program to test excavation methods in a 500 m deep Callovo Oxfordian clay-stone to demonstrate feasibility of nuclear waste disposal Different types of drift excavations and reinforcements methods has been and will be tested at the URL,in order to evaluate the impact on the surrounding rock behavior, especially the EDZ, and to optimize the design of the reinforcement. At the beginning soft support has been used to let drifts converge, and from time to time the stiffness of support has been increase up to emplace gasketed pre-cast concrete segmental rings just after an open face tunneling excavation end of 2013. In this previous experiment, the target was to apply and on a short time a stiff reinforcement that can have a similar behavior as a pre-cast concrete ring. This paper will present the experimental layout, the measurement tools as well as the first results. The instrumented drift section 'BPE' is 15 m long and 6,3 m diameter; it was excavated by a BRH machine. The excavation sequence was realized with a one meter excavation pass. After each pass, a 10 cm layer of wet mixed fiber reinforced shotcrete was applied on the vault, and 45 cm on the counter vault. The vault 45 cm thickness was reached after three other layers added respectively while proceeding with the three following pass of excavation. Different kinds of measurements were carried out before, during and after excavation, in a way to evaluate the loading of the shotcrete reinforcement as well as the hydro-mechanical behavior of the host rock. Before the excavation of the drift, three standard diameter boreholes have been drilled around the planned drift. They have been equipped with pressure and deformation measurements in a way to monitor the hydro-mechanical impact of the excavation on the surrounding rock. While excavating, the

  3. On the Use of the Instrumented Charpy-V Impact Signal for Assessment of RPVS Embrittlement

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, A; van Walle, E; Van de Velde, J; Chaouadi, R; Puzzolante, J L; Van Ransbeeck, Th; Verstrepen, A

    1994-04-01

    In the context of LWR pressure vessel surveillance, the significance of the Cv notch impact test, instrumented by strain gages, has been revisited. The load diagram - general yield, maximum, brittle fracture and arrest loads versus temperature - is the most fundamental feature of the test. It is directly correlated to the appearance (percentage shear) of the fracture surface, and also constitutes a straightforward expression of the davidenkov diagram, by which DBTT shifts are linked to damage mechanisms. In combination with static uniaxial tensile tests, it allows to quantify strain rate effects on the yielding and work hardening capability of the steel. By contrast, the bulk of the absorbed energy and lateral expansion stems from plastic deformation, associated to ductile stable crack growth under conditions unrepresentative of the constraints and stress-strain field near the tip of a sharp crack in a pressure vessel. It has been shown that the temperature at which a fixed energy is absorbed in the test (41 or 68 J) cannot always trace, to acceptable accuracy, the effect of steel service exposure on the ductile-brittle transition temperature DBTT and on cleavage fracture toughness. It is contented that this can be done more reliably by using characteristic temperatures of the load diagram. The engineering and regulatory implications of this physically- grounded dynamic fracture toughness indexation approach are reported. Some related findings relative to damage mechanisms and strain ageing effects are outlined.

  4. On the Use of the Instrumented Charpy-V Impact Signal for Assessment of RPVS Embrittlement

    International Nuclear Information System (INIS)

    Fabry, A.; van Walle, E.; Van de Velde, J.; Chaouadi, R.; Puzzolante, J.L.; Van Ransbeeck, Th.; Verstrepen, A.

    1994-04-01

    In the context of LWR pressure vessel surveillance, the significance of the Cv notch impact test, instrumented by strain gages, has been revisited. The load diagram - general yield, maximum, brittle fracture and arrest loads versus temperature - is the most fundamental feature of the test. It is directly correlated to the appearance (percentage shear) of the fracture surface, and also constitutes a straightforward expression of the davidenkov diagram, by which DBTT shifts are linked to damage mechanisms. In combination with static uniaxial tensile tests, it allows to quantify strain rate effects on the yielding and work hardening capability of the steel. By contrast, the bulk of the absorbed energy and lateral expansion stems from plastic deformation, associated to ductile stable crack growth under conditions unrepresentative of the constraints and stress-strain field near the tip of a sharp crack in a pressure vessel. It has been shown that the temperature at which a fixed energy is absorbed in the test (41 or 68 J) cannot always trace, to acceptable accuracy, the effect of steel service exposure on the ductile-brittle transition temperature DBTT and on cleavage fracture toughness. It is contented that this can be done more reliably by using characteristic temperatures of the load diagram. The engineering and regulatory implications of this physically- grounded dynamic fracture toughness indexation approach are reported. Some related findings relative to damage mechanisms and strain ageing effects are outlined

  5. The Impact of Crosstalk in the X-IFU Instrument on Athena Science Cases

    Science.gov (United States)

    Hartog, R. Den; Peille, P.; Dauser, T.; Jackson, B.; Bandler, S.; Barret, D.; Brand, T.; Herder, J-W Den; Kiviranta, M.; Kuur, J. Van Der; hide

    2016-01-01

    In this paper we present a first assessment of the impact of various forms of instrumental crosstalk on the science performance of the X-ray Integral Field Unit (X-IFU) on the Athena X-ray mission. This assessment is made using the SIXTE end-to-end simulator in the context of one of the more technically challenging science cases for the XIFU instrument. Crosstalk considerations may influence or drive various aspects of the design of the array of high-count-rate Transition Edge Sensor (TES) detectors and its Frequency Domain Multiplexed (FDM) readout architecture. The Athena X-ray mission was selected as the second L-class mission in ESA's Cosmic Vision 2015–25 plan, with alaunch foreseen in 2028, to address the theme ''Hot and Energetic Universe"1. One of the two instruments on boardAthena is the X-ray Integral Field Unit2 (X-IFU) which is based on an array of 3800 Transition Edge Sensors (TES's)operated at a temperature of 90 mK. The science cases pose an interesting challenge for this instrument, as they requirea combination of high energy resolution (2.5 eV FWHM or better), high spatial resolution (5 arcsec or better) and highcount rate capability (several tens of counts per second per detector for point sources as bright as 10 mCrab).The performance at the single sensor level has been demonstrated3, but the operation of such detectors in an array, usingmultiplexed readout, brings additional challenges, both for the design of the array in which the sensors are placed and forthe readout of the sensors. The readout of the detector array will be based on Frequency Domain Multiplexing (FDM)4.In this system of detectors and readout, crosstalk can arise through various mechanisms: on the TES array, neighboringsensors can couple through thermal crosstalk. Detectors adjacent in carrier frequency may suffer from electrical crosstalkdue to the finite width of the bandpass filters, and shared sources of impedance in their signal lines. The signals from theindividual

  6. Pavlovian-to-instrumental transfer: A new paradigm to assess pathological mechanisms with regard to the use of Internet applications.

    Science.gov (United States)

    Vogel, Verena; Kollei, Ines; Duka, Theodora; Snagowski, Jan; Brand, Matthias; Müller, Astrid; Loeber, Sabine

    2018-07-16

    At present, there is a considerable lack of human studies that investigated the impact of conditioned cues on instrumental responding although these processes are considered as core mechanisms contributing to the development and maintenance of addictive behaviours. No studies are available that assessed these processes with regard to Internet gaming or Internet shopping applications. We thus developed a Pavlovian-to-instrumental transfer (PIT)-Paradigm implementing appetitive stimuli related to Internet gaming and Internet shopping applications and investigated whether an outcome-specific PIT-Effect is observed. In addition, we assessed whether the problematic use of gaming or shopping applications, personality traits and stress would affect the acquisition of knowledge of the experimental contingencies during Pavlovian training and the impact of conditioned stimuli on instrumental responding. A PIT-Paradigm, screenings for Internet gaming disorder and Internet shopping disorder (s-IAT), and questionnaires on personality traits (NEO-FFI, BIS-15) and perceived stress (PSQ20) were administered to sixty-six participants. The PIT-Paradigm demonstrated the effects of stimuli conditioned to rewards related to Internet gaming and Internet shopping applications on instrumental responding to obtain such rewards. Findings also indicated that severity of problematic Internet gaming, but not Internet shopping, contributed to the acquisition of knowledge of the experimental contingencies. Stress, extraversion, neuroticism and gender emerged as further predictors. The strength of expectancy of the different reinforcers affected the 'gaming PIT'-Effect; however, none of the variables assessed in the present study showed any effect on the 'shopping PIT'-Effect. Future studies including participants with pathological use patterns that can be classified as internet use disorder are warranted to extend these findings. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Conceptual phase A design of a cryogenic shutter mechanism for the SAFARI flight instrument

    Science.gov (United States)

    Eigenmann, Max; Wehmeier, Udo J.; Vuilleumier, Aurèle; Messina, Gabriele; Meyer, Michael R.

    2012-09-01

    We present a conceptual design for a cryogenic optical mechanism for the SAFARI instrument. SAFARI is a long wavelength (34-210 micron) Imaging Fourier Transform Spectrometer (FTS) to fly as an ESA instrument on the JAXA SPICA mission projected to launch in 2021. SPICA is a large 3m class space telescope which will have an operating temperature of less than 7K. The SAFARI shutter is a single point of failure flight mechanism designed to operate in space at a temperature of 4K which meets redundancy and reliability requirements of this challenging mission. The conceptual design is part of a phase A study led by ETH Institute for Astronomy and conducted by RUAG Space AG.

  8. Instrumented mouthguard acceleration analyses for head impacts in amateur rugby union players over a season of matches.

    Science.gov (United States)

    King, Doug; Hume, Patria A; Brughelli, Matt; Gissane, Conor

    2015-03-01

    Direct impacts with the head (linear acceleration or pressure) and inertial loading of the head (rotational acceleration or strain) have been postulated as the 2 major mechanisms of head-related injuries such as concussion. Although data are accumulating for soccer and American football, there are no published data for nonhelmeted collision sports such as rugby union. To quantify head impacts via instrumented mouthguard acceleration analyses for rugby union players over a season of matches. Descriptive epidemiology study. Data on impact magnitude and frequency were collected with molded instrumented mouthguards worn by 38 premier amateur senior rugby players participating in the 2013 domestic season of matches. A total of 20,687 impacts >10g (range, 10.0-164.9g) were recorded over the duration of the study. The mean ± SD number of impacts per player over the duration of the season of matches was 564 ± 618, resulting in a mean ± SD of 95 ± 133 impacts to the head per player, per match over the duration of the season of matches. The impact magnitudes for linear accelerations were skewed to the lower values (Sp = 3.7 ± 0.02; P rugby union players over a season of matches, measured via instrumented mouthguard accelerations, were higher than for most sports previously reported. Mean linear acceleration measured over a season of matches was similar to the mean linear accelerations previously reported for youth, high school, and collegiate American football players but lower than that for female youth soccer players. Mean rotational acceleration measured over a season of matches was similar to mean rotational accelerations for youth, high school, and collegiate American football players but less than those for female youth soccer players, concussed American collegiate players, collegiate American football players, and professional American football players. © 2014 The Author(s).

  9. Mechanical properties of aluminium honeycomb impact limiters

    International Nuclear Information System (INIS)

    Maji, A.K.; Satpathi, D.; Donald, S.

    1992-01-01

    Aluminium honeycombs have been extensively used as impact limiters in nuclear waste transport casks. The mechanical behaviour of these shock absorbing materials was studied to develop an extensive experimental database. A series of tests were performed along various loading paths. Different densities of aluminium honeycombs were tested in different orientations. Static tests included uniaxial tension, uniaxial compression and torsion. Dynamic tests were conducted at different strain rates of up to 100 s -1 , to generate experimental data relevant to accident situations. Dynamic studies included the effects of specimen size and confinement. The purpose of using different loading paths was to generate an extensive experimental database which may also be used to develop constitutive models for these materials. Design charts were constructed which can be accessed by various cask designers to optimise and economise on cask development. (Author)

  10. Mechanical Design of NESSI: New Mexico Tech Extrasolar Spectroscopic Survey Instrument

    Science.gov (United States)

    Santoro, Fernando G.; Olivares, Andres M.; Salcido, Christopher D.; Jimenez, Stephen R.; Jurgenson, Colby A.; Hrynevych, Michael A.; Creech-Eakman, Michelle J.; Boston, Penny J.; Schmidt, Luke M.; Bloemhard, Heather; hide

    2011-01-01

    NESSI: the New Mexico Tech Extrasolar Spectroscopic Survey Instrument is a ground-based multi-object spectrograph that operates in the near-infrared. It will be installed on one of the Nasmyth ports of the Magdalena Ridge Observatory (MRO) 2.4-meter Telescope sited in the Magdalena Mountains, about 48 km west of Socorro-NM. NESSI operates stationary to the telescope fork so as not to produce differential flexure between internal opto-mechanical components during or between observations. An appropriate mechanical design allows the instrument alignment to be highly repeatable and stable for both short and long observation timescales, within a wide-range of temperature variation. NESSI is optically composed of a field lens, a field de-rotator, re-imaging optics, an auto-guider and a Dewar spectrograph that operates at LN2 temperature. In this paper we report on NESSI's detailed mechanical and opto-mechanical design, and the planning for mechanical construction, assembly, integration and verification.

  11. Interaction of the EU ETS and national climate policy instrumentsImpact on biomass use

    International Nuclear Information System (INIS)

    Kautto, N.; Arasto, A.; Sijm, J.; Peck, P.

    2012-01-01

    Policy-makers apply multiple policy instruments simultaneously in the climate and energy policy field at both EU and Member State levels. This creates interactions between instruments that can be complementary and synergistic but also conflicting. This article focuses on the interactions of climate policy instruments and their impact on biomass use. The objectives are to examine interactions of the EU Emissions Trading System (EU ETS) with the main national climate policy instruments and to identify the influence of these on biomass use. The work draws experiences from seven EU countries (Austria, Finland, Germany, the Netherlands, Poland, Sweden and the United Kingdom), with a special focus on Finland and Sweden. The analysis explores the effects of policy interactions and is based on an examination of literature, and interviews with biomass experts in research, industry and policy spheres. Results indicate that the combined effects of climate policy instruments have a tangible impact on biomass use, whereas the causal links to the EU ETS are difficult to assess separately. Policy impacts found include increased competition for biomass resources, changes in fuel mixes and a contribution to upward pressure on wood prices. Differences in these effects are linked to differing national policy mixes and energy-carrier portfolios – an example being the relative differences in the importance of peat to the energy mix in Finland and Sweden. Analysis and comparison of the effects in the selected countries can yield insight on how to improve the design of policy interventions that impact biomass use. This study confirms the importance of identifying interactions between policy instruments so as to recognise – and manage – synergies and conflicts. The development of more synergistic and coordinated policy instrument mixes would also be beneficial for the bioenergy field. -- Highlights: ► Combined effects of climate policy instruments have a tangible impact on biomass

  12. Evaluating the effectiveness of impact assessment instruments: Theorising the nature and implications of their political constitution

    International Nuclear Information System (INIS)

    Cashmore, Matthew; Richardson, Tim; Hilding-Ryedvik, Tuija; Emmelin, Lars

    2010-01-01

    The central role of impact assessment instruments globally in policy integration initiatives has been cemented in recent years. Associated with this trend, but also reflecting political emphasis on greater accountability in certain policy sectors and a renewed focus on economic competitiveness in Western countries, demand has increased for evidence that these instruments are effective (however defined). Resurgent interest in evaluation has not, however, been accompanied by the conceptual developments required to redress longstanding theoretical problems associated with such activities. In order to sharpen effectiveness evaluation theory for impact assessment instruments this article critically examines the neglected issue of their political constitution. Analytical examples are used to concretely explore the nature and significance of the politicisation of impact assessment. It is argued that raising awareness about the political character of impact assessment instruments, in itself, is a vital step in advancing effectiveness evaluation theory. Broader theoretical lessons on the framing of evaluation research are also drawn from the political analysis. We conclude that, at least within the contemporary research context, learning derived from analysing the meaning and implications of plural interpretations of effectiveness represents the most constructive strategy for advancing impact assessment and policy integration theory.

  13. Biomass power generation in competitive markets - The impact of instruments and regulations

    International Nuclear Information System (INIS)

    Ackermann, Thomas; Soeder, Lennart

    1999-01-01

    This paper presents and briefly evaluates the most important existing market instruments and market schemes which support the development of renewable energy generation as well as the impact of market regulations on the development of biomass power generation. The evaluation of the existing instruments focuses on the incentives provided by the various instruments to reduce production costs. The instruments and schemes are: Feed-in Tariffs, Net Metering, Bidding Process, Fixed Quotas, Green Certificate Trading, Green Power Exchange, Green Pricing. Feed-in tariffs and net metering are important instruments to get the different technologies 'off the ground', however, they can only be considered an interim solution as they do not necessarily lead to cost reduction. A bidding process is one way to achieve these cost reductions, but high transaction costs will support the development of large renewable energy projects, which is not always the desired effect. Fixed quotas combined with green certificate trading or a power exchange in combination with Green Pricing seem to lead to similar costs reduction, however, so far there is only limited experience with such instruments. The analysis of the impact of market regulations focuses on international electricity markets with a power exchange. Such markets exist, for example, in Scandinavia, England and Wales, Australia, New Zealand and California. The analysis showed that new distributed generation, for example based on biomass, faces significant market barriers. Furthermore, distributed generation is not treated equally within the market regulations compared to large-scale power generation

  14. Behavioral and neurobiological mechanisms of extinction in Pavlovian and instrumental learning.

    Science.gov (United States)

    Todd, Travis P; Vurbic, Drina; Bouton, Mark E

    2014-02-01

    This article reviews research on the behavioral and neural mechanisms of extinction as it is represented in both Pavlovian and instrumental learning. In Pavlovian extinction, repeated presentation of a signal without its reinforcer weakens behavior evoked by the signal; in instrumental extinction, repeated occurrence of a voluntary action without its reinforcer weakens the strength of the action. In either case, contemporary research at both the behavioral and neural levels of analysis has been guided by a set of extinction principles that were first generated by research conducted at the behavioral level. The review discusses these principles and illustrates how they have informed the study of both Pavlovian and instrumental extinction. It shows that behavioral and neurobiological research efforts have been tightly linked and that their results are readily integrated. Pavlovian and instrumental extinction are also controlled by compatible behavioral and neural processes. Since many behavioral effects observed in extinction can be multiply determined, we suggest that the current close connection between behavioral-level and neural-level analyses will need to continue. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Policy instruments to decrease the climate impact of housing, personal transport and food. Detailed instrument descriptions; Ohjauskeinoja asumisen, henkiloeliikenteen ja ruoan ilmastovaikutusten hillintaeaen. Yksityiskohtaiset ohjauskeinokuvaukset

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, E.; Perrels, A.; Nissinen, A.; Berghaell, E.; Liesimaa, V.; Mattinen, M. (eds.)

    2012-03-15

    Reducing consumption volumes or introducing climate conscious consumption patterns can be efficient ways to mitigate climate change. Twenty existing policy instruments affecting the greenhouse gas emissions of housing, passenger traffic and food are described in this report of the KUILU-project. The policy instruments and the possibilities to develop effective instrument packages were discussed in two expert workshops, the results of which are presented in annexes of this report. There are already several policy instruments that target on housing and passenger traffic. Their differences in estimated emission reductions are large, which can ease the prioritization and selection of the instruments for further development. So far, only one policy instrument exists that aims to reduce the climate impacts of food choices, namely a Council of State Decision of Principle on Promoting Sustainability in Public Purchasing. However, it includes several measures that can be used to influence private companies and citizens, and thus it opens the field of policy instrument for mitigation of climate impacts of food. According to the expert survey, the most effective policy instrument involved in the analysis was building regulations, and the four most effective instruments after this were the following: gradated procurement tax of cars based on emissions, gradation of car tax, taxation of transport fuels, energy taxes of housing, and the effect of ecodesign directive on appliances. The effectiveness of policy instruments related to food was assessed to be on average level. The five least effective instruments were: EU energy label, voluntary energy experts, the tax of beverage packing, energy certificates, and subsidies for energy efficiency reparation in buildings. However, the expert opinions on the effectiveness of the policy instruments varied significantly. After this report, the KUILU project continued with an analysis of the policy instrument packages and with suggestions

  16. Policy instruments to decrease the climate impact of housing, personal transport and food. Detailed instrument descriptions; Ohjauskeinoja asumisen, henkiloeliikenteen ja ruoan ilmastovaikutusten hillintaeaen. Yksityiskohtaiset ohjauskeinokuvaukset

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, E.; Perrels, A.; Nissinen, A.; Berghaell, E.; Liesmaa, V.; Mattinen, M. (eds.)

    2012-07-01

    Reducing consumption volumes or introducing climate conscious consumption patterns can be efficient ways to mitigate climate change. Twenty existing policy instruments affecting the greenhouse gas emissions of housing, passenger traffic and food are described in this report of the KUILU-project. The policy instruments and the possibilities to develop effective instrument packages were discussed in two expert workshops, the results of which are presented in annexes of this report. There are already several policy instruments that target on housing and passenger traffic. Their differences in estimated emission reductions are large, which can ease the prioritization and selection of the instruments for further development. So far, only one policy instrument exists that aims to reduce the climate impacts of food choices, namely a Council of State Decision of Principle on Promoting Sustainability in Public Purchasing. However, it includes several measures that can be used to influence private companies and citizens, and thus it opens the field of policy instrument for mitigation of climate impacts of food. According to the expert survey, the most effective policy instrument involved in the analysis was building regulations, and the four most effective instruments after this were the following: gradated procurement tax of cars based on emissions, gradation of car tax, taxation of transport fuels, energy taxes of housing, and the effect of ecodesign directive on appliances. The effectiveness of policy instruments related to food was assessed to be on average level. The five least effective instruments were: EU energy label, voluntary energy experts, the tax of beverage packing, energy certificates, and subsidies for energy efficiency reparation in buildings. However, the expert opinions on the effectiveness of the policy instruments varied significantly. After this report, the KUILU project continued with an analysis of the policy instrument packages and with suggestions

  17. Validation of an instrumented dummy to assess mechanical aspects of discomfort during load carriage.

    Directory of Open Access Journals (Sweden)

    Patrick D Wettenschwiler

    Full Text Available Due to the increasing load in backpacks and other load carriage systems over the last decades, load carriage system designs have to be adapted accordingly to minimize discomfort and to reduce the risk of injury. As subject studies are labor-intensive and include further challenges such as intra-subject and inter-subject variability, we aimed to validate an instrumented dummy as an objective laboratory tool to assess the mechanical aspects of discomfort. The validation of the instrumented dummy was conducted by comparison with a recent subject study. The mechanical parameters that characterize the static and dynamic interaction between backpack and body during different backpack settings were compared. The second aim was to investigate whether high predictive power (coefficient of determination R2>0.5 in assessing the discomfort of load carriage systems could be reached using the instrumented dummy. Measurements were conducted under static conditions, simulating upright standing, and dynamic conditions, simulating level walking. Twelve different configurations of a typical load carriage system, a commercially available backpack with a hip belt, were assessed. The mechanical parameters were measured in the shoulder and the hip region of the dummy and consisted of average pressure, peak pressure, strap force and relative motion between the system and the body. The twelve configurations consisted of three different weights (15kg, 20kg, and 25kg, combined with four different hip belt tensions (30N, 60N, 90N, and 120N. Through the significant (p<0.05 correlation of the mechanical parameters measured on the dummy with the corresponding values of the subject study, the dummy was validated for all static measurements and for dynamic measurements in the hip region to accurately simulate the interaction between the human body and the load carriage system. Multiple linear regressions with the mechanical parameters measured on the dummy as independent

  18. On the use of the instrumented Charpy-V impact signal for assessment of RPVS embrittlement

    Energy Technology Data Exchange (ETDEWEB)

    Fabry, A.; Van Walle, E.; Van de Velde, J.; Chauoadi, R.; Puzzolante, J.L.; Van Ransbeeck, Th.; Verstrepen, A.

    1995-12-01

    In the context of LWR pressure vessel surveillance, the significance of the Cv notch impact test instrumented by strain gages has been revised. The load diagram (general yield, maximum, brittle fracture and arrest loads versus temperature ) is the most fundamental feature of the test. It is directly correlated to the appearance (percentage shear) of the fracture surface and also constitutes a straightforward experimental expression of the Davidenkov diagram, by which ductile-brittle transition temperature shifts are linked to irradiation damage mechanisms. In combination with static uniaxial tensile tests, it allows quantification of strain rate effects on the yielding and work hardening capacity of the steel. By contrast, the bulk of the absorbed energy and lateral expansion stems from ductile stable crack growth associated with plastic deformation under conditions, unrepresentative of the constraints and stress-strain field near the tip of a sharp crack in a pressure vessel. It is shown that the temperature at which fixed energy is absorbed in the test (41 or 68 Joules) cannot always trace to acceptable accuracy the effect of steel service exposure on the ductile - brittle transition temperature and on cleavage fracture toughness. It is contented that this can be done more reliably by using characteristic temperatures of the load diagram. An attempt to determine the engineering and regulatory implications of this physically-grounded fracture toughness approach is made.

  19. On the use of the instrumented Charpy-V impact signal for assessment of RPVS embrittlement

    International Nuclear Information System (INIS)

    Fabry, A.; Van Walle, E.; Van de Velde, J.; Chauoadi, R.; Puzzolante, J.L.; Van Ransbeeck, Th.; Verstrepen, A.

    1995-12-01

    In the context of LWR pressure vessel surveillance, the significance of the Cv notch impact test instrumented by strain gages has been revised. The load diagram (general yield, maximum, brittle fracture and arrest loads versus temperature ) is the most fundamental feature of the test. It is directly correlated to the appearance (percentage shear) of the fracture surface and also constitutes a straightforward experimental expression of the Davidenkov diagram, by which ductile-brittle transition temperature shifts are linked to irradiation damage mechanisms. In combination with static uniaxial tensile tests, it allows quantification of strain rate effects on the yielding and work hardening capacity of the steel. By contrast, the bulk of the absorbed energy and lateral expansion stems from ductile stable crack growth associated with plastic deformation under conditions, unrepresentative of the constraints and stress-strain field near the tip of a sharp crack in a pressure vessel. It is shown that the temperature at which fixed energy is absorbed in the test (41 or 68 Joules) cannot always trace to acceptable accuracy the effect of steel service exposure on the ductile - brittle transition temperature and on cleavage fracture toughness. It is contented that this can be done more reliably by using characteristic temperatures of the load diagram. An attempt to determine the engineering and regulatory implications of this physically-grounded fracture toughness approach is made

  20. Low velocity instrumented impact testing of four new damage tolerant carbon/epoxy composite systems

    Science.gov (United States)

    Lance, D. G.; Nettles, A. T.

    1990-01-01

    Low velocity drop weight instrumented impact testing was utilized to examine the damage resistance of four recently developed carbon fiber/epoxy resin systems. A fifth material, T300/934, for which a large data base exists, was also tested for comparison purposes. A 16-ply quasi-isotropic lay-up configuration was used for all the specimens. Force/absorbed energy-time plots were generated for each impact test. The specimens were cross-sectionally analyzed to record the damage corresponding to each impact energy level. Maximum force of impact versus impact energy plots were constructed to compare the various systems for impact damage resistance. Results show that the four new damage tolerant fiber/resin systems far outclassed the T300/934 material. The most damage tolerant material tested was the IM7/1962 fiber/resin system.

  1. Beachrock occurrence, characteristics, formation mechanisms and impacts

    Science.gov (United States)

    Vousdoukas, M. I.; Velegrakis, A. F.; Plomaritis, T. A.

    2007-11-01

    Beachrocks are hard coastal sedimentary formations consisting of various beach sediments, lithified through the precipitation of carbonate cements. The objectives of this contribution are to (a) collate and review information on the reported occurrences, characteristics and formation mechanisms of beachrocks and (b) consider their impacts on the coastal zone. The analysis of the available information has shown that (a) beachrock formation is a global and diachronic phenomenon and (b) the great majority of beachrocks are found in tropical/subtropical and low temperate latitude, microtidal coasts. The cementing agents of beachrocks are composed predominantly of the metastable carbonate phases High Magnesian Calcite (HMC) and Aragonite (Ar), appearing in a diverse crystalline morphology. It has been suggested that cement precipitation in the coastal environment is controlled by: (i) the physicochemical conditions; (ii) the presence of organic compounds and microbes; (iii) the magnitude and distribution of the wave energy along the coast; and (iv) the textural characteristics of the constituent sediments. Various theories have been proposed to explain beachrock formation itself, linking the phenomenon to either physicochemical or biological processes. These theories, however, do not seem to be of universal validity and acceptance, as each is able to explain only some of the reported occurrences. The presence of beachrocks appears to affect beach morphodynamics by: (i) 'locking' the beach profile; (ii) modifying the nearshore hydrodynamics; (iii) changing the porous character of the beach and, thus, its response to wave forcing; and (iv) differential bed erosion at the margins of the beachrock outcrops that can alter significantly the long- and, particularly, the cross-shore sediment transport. Therefore, although relict submerged beachrock outcrops may provide some coastal protection by reducing the wave energy impinging onto the coastline, modern beachrocks may

  2. The impact of the long-term playing of musical instruments on the stomatognathic system - review.

    Science.gov (United States)

    Głowacka, Arleta; Matthews-Kozanecka, Maja; Kawala, Maciej; Kawala, Beata

    2014-01-01

    In this article, we have made a review of the influence of playing musical instruments on the formation of malocclusion and TMJ disorders in musicians. Primary attention was paid to the effects of wind and stringed instruments. The aim of the article was the presentation of research and opinions about this problem in the last 25 years. It is reported that long-term and repetitive playing of musical instruments, particularly stringed (violin and viola) and wind instruments can cause dysfunctions of the stomatognathic system. The impact of wind instruments was assessed in terms of the type of mouthpiece. We studied the possibility of repositioning the front teeth and reducing the width of the upper dental arch and overbite. There were also reports on the use of a specific instrument to improve the child's occlusion. Studies have also been performed on the usefulness of relaxation plates in order to improve, and even prevent, dysfunction caused by the constant stress on the same parts of the stomatognathic system. The experiments were mainly based on interviews, dental cast analyses and cephalometric analyses. Additional methods were dynamometer tests and muscle tension palpation.

  3. Development and Validation of Mechanical Engineering Trade Skills Assessment Instrument for Sustainable Job Security in Yobe State

    Science.gov (United States)

    Adamu, Gishua Garba; Dawha, Josphine Musa; Kamar, Tiamiyu Salihu

    2015-01-01

    Mechanical Engineering Trade Skills Assessment Instrument (METSAI) is aimed at determining the extent to which students have acquired practical skills before graduation that will enable them get employment for sustainable job security in Yobe state. The study employed instrumentation research design. The populations of the study were 23 mechanical…

  4. Measuring mechanisms for quality assurance in primary care systems in transition: test of a new instrument in Slovenia and Uzbekistan.

    NARCIS (Netherlands)

    Kringos, D.S.; Boerma, W.G.W.; Pellny, M.

    2009-01-01

    Aim: This WHO study, carried out by the authors, aimed to develop and field test an instrument to assess the availability of structures and mechanisms for managing quality in primary care in countries in transition. Methods: The instrument is based on a literature study, consensus meetings with

  5. Relationship of vibro-mechanical properties and microstructure of wood and varnish interface in string instruments

    Science.gov (United States)

    Sedighi Gilani, Marjan; Pflaum, Johanna; Hartmann, Stefan; Kaufmann, Rolf; Baumgartner, Michael; Schwarze, Francis Willis Mathew Robert

    2016-04-01

    Wood varnish coatings not only are aesthetically important, but also preserve the musical instrument from wear and fluctuations in the ambient humidity. Depending on the thickness, extent of penetration into the wood and the physical and mechanical properties after hardening, varnishes may change the mechanical and also vibro-acoustical properties of the coated wood. Contrary to studies on the chemistry of the varnish and primer used for old and contemporary musical instruments, the physical and mechanical properties of the varnished wood in relation to the geometry of their interface have been poorly studied. We implemented non-destructive test methods, i.e., vibration tests and X-ray tomography, to characterize the hardening-dependent change in the vibrational properties of master grade tone wood specimens after coating with four different varnishes. Two were manufactured in the laboratory, and two were supplied from master violin makers. For a controlled accelerated hardening of the varnish, a UV exposure method was used. It was demonstrated that varnishes increase wood damping, along and perpendicular to the grain directions. Varnishes reduce the sound radiation along the grain, but increase it in the perpendicular direction. Changes in the vibrational properties were discussed together with results of 3D images of wood and varnish microstructure, obtained from a customized tabletop X-ray microtomographic setup. For comparison, the microstructure of the interface of the varnished wood in the laboratory and of specimens from two old violins was analyzed with the same X-ray tomography setup. Laboratory varnishes with various compositions penetrated differently into the wood structure. One varnish of a master grade old violin had a higher density and was also thicker and penetrated weaker into the wood, which is more likely related to a more sophisticated primer and varnish application. The study demonstrates the importance of the vibro-mechanical properties of

  6. Impact of proof test interval and coverage on probability of failure of safety instrumented function

    International Nuclear Information System (INIS)

    Jin, Jianghong; Pang, Lei; Hu, Bin; Wang, Xiaodong

    2016-01-01

    Highlights: • Introduction of proof test coverage makes the calculation of the probability of failure for SIF more accurate. • The probability of failure undetected by proof test is independently defined as P TIF and calculated. • P TIF is quantified using reliability block diagram and simple formula of PFD avg . • Improving proof test coverage and adopting reasonable test period can reduce the probability of failure for SIF. - Abstract: Imperfection of proof test can result in the safety function failure of safety instrumented system (SIS) at any time in its life period. IEC61508 and other references ignored or only elementarily analyzed the imperfection of proof test. In order to further study the impact of the imperfection of proof test on the probability of failure for safety instrumented function (SIF), the necessity of proof test and influence of its imperfection on system performance was first analyzed theoretically. The probability of failure for safety instrumented function resulted from the imperfection of proof test was defined as probability of test independent failures (P TIF ), and P TIF was separately calculated by introducing proof test coverage and adopting reliability block diagram, with reference to the simplified calculation formula of average probability of failure on demand (PFD avg ). Research results show that: the shorter proof test period and the higher proof test coverage indicate the smaller probability of failure for safety instrumented function. The probability of failure for safety instrumented function which is calculated by introducing proof test coverage will be more accurate.

  7. The opto-mechanical design for GMOX: a next-generation instrument concept for Gemini

    Science.gov (United States)

    Smee, Stephen A.; Barkhouser, Robert; Robberto, Massimo; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy M.

    2016-08-01

    We present the opto-mechanical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph, a potential next-generation (Gen-4 #3) facility-class instrument for Gemini. GMOX is a wide-band, multi-object, spectrograph with spectral coverage spanning 350 nm to 2.4 um with a nominal resolving power of R 5000. Through the use of Digital Micromirror Device (DMD) technology, GMOX will be able to acquire spectra from hundreds of sources simultaneously, offering unparalleled flexibility in target selection. Utilizing this technology, GMOX can rapidly adapt individual slits to either seeing-limited or diffraction-limited conditions. The optical design splits the bandpass into three arms, blue, red, and near infrared, with the near-infrared arm being split into three channels covering the Y+J band, H band, and K band. A slit viewing camera in each arm provides imaging capability for target acquisition and fast-feedback for adaptive optics control with either ALTAIR (Gemini North) or GeMS (Gemini South). Mounted at the Cassegrain focus, GMOX is a large (1.3 m x 2.8 m x 2.0 m) complex instrument, with six dichroics, three DMDs (one per arm), five science cameras, and three acquisition cameras. Roughly half of these optics, including one DMD, operate at cryogenic temperature. To maximize stiffness and simplify assembly and alignment, the opto-mechanics are divided into three main sub-assemblies, including a near-infrared cryostat, each having sub-benches to facilitate ease of alignment and testing of the optics. In this paper we present the conceptual opto-mechanical design of GMOX, with an emphasis on the mounting strategy for the optics and the thermal design details related to the near-infrared cryostat.

  8. Mechanisms Fostering Social Entrepreneurship as Potential Instruments for Economic Development: The Eastern Partnership Perspective

    Directory of Open Access Journals (Sweden)

    Plotnieks Dāvis

    2014-10-01

    Full Text Available With its plan to assign 600 million euros through the European Neighbourhood Instrument for Eastern Partnership countries, the European Union intended to increase the efficiency of institutions, attenuate social problems, and create an environment that fosters economic growth and human well-being in Armenia, Azerbaijan, Belarus, Georgia, Moldova, and Ukraine. A few scholars have criticized the amount of funding and planned initiatives of the European Neighbourhood Instrument as insufficient and suggested that in order to foster cooperation and support reforms in its Eastern Partnership countries, more action should be taken. In times when European Commission budget is under constraints of consolidation and increase of aid for supporting European Neighbourhood countries is hardly possible, alternative solutions for tempering social problems need to be assessed. Various scientists, philanthropists and entrepreneurs see social entrepreneurship as a tool for solving social problems in a sustainable way where business thinking is being combined with non-profit philosophy. Contrary to government support and intervention for solving social problems, social entrepreneurship is already being used as tool that initially addresses joint needs--solve social problems and create revenue that provides much needed income for sustainable business initiatives. This paper analyzes the concept of social entrepreneurship, examples where social entrepreneurship is solving social problems, and mechanisms that can foster these phenomena. The aim of this paper is to examine different mechanisms of how governments can foster the creation and development of social entrepreneurship. Unique survey data derived from a project examining social entrepreneurship in Europe is used. It is concluded that by adopting mechanisms proven in various developed countries, the Eastern Partnership countries can stimulate social entrepreneurship, thus attenuating social problems and

  9. Head-impact mechanisms in men's and women's collegiate ice hockey.

    Science.gov (United States)

    Wilcox, Bethany J; Machan, Jason T; Beckwith, Jonathan G; Greenwald, Richard M; Burmeister, Emily; Crisco, Joseph J

    2014-01-01

    Concussion injury rates in men's and women's ice hockey are reported to be among the highest of all collegiate sports. Quantification of the frequency of head impacts and the magnitude of head acceleration as a function of the different impact mechanisms (eg, head contact with the ice) that occur in ice hockey could provide a better understanding of this high injury rate. To quantify and compare the per-game frequency and magnitude of head impacts associated with various impact mechanisms in men's and women's collegiate ice hockey players. Cohort study. Collegiate ice hockey rink. Twenty-three men and 31 women from 2 National Collegiate Athletic Association Division I ice hockey teams. We analyzed magnitude and frequency (per game) of head impacts per player among impact mechanisms and between sexes using generalized mixed linear models and generalized estimating equations to account for repeated measures within players. Participants wore helmets instrumented with accelerometers to allow us to collect biomechanical measures of head impacts sustained during play. Video footage from 53 games was synchronized with the biomechanical data. Head impacts were classified into 8 categories: contact with another player; the ice, boards or glass, stick, puck, or goal; indirect contact; and contact from celebrating. For men and women, contact with another player was the most frequent impact mechanism, and contact with the ice generated the greatest-magnitude head accelerations. The men had higher per-game frequencies of head impacts from contact with another player and contact with the boards than did the women (P < .001), and these impacts were greater in peak rotational acceleration (P = .027). Identifying the impact mechanisms in collegiate ice hockey that result in frequent and high-magnitude head impacts will provide us with data that may improve our understanding of the high rate of concussion in the sport and inform injury-prevention strategies.

  10. Mechanisms controlling the impact of multi-year drought on mountain hydrology.

    Science.gov (United States)

    Bales, Roger C; Goulden, Michael L; Hunsaker, Carolyn T; Conklin, Martha H; Hartsough, Peter C; O'Geen, Anthony T; Hopmans, Jan W; Safeeq, Mohammad

    2018-01-12

    Mountain runoff ultimately reflects the difference between precipitation (P) and evapotranspiration (ET), as modulated by biogeophysical mechanisms that intensify or alleviate drought impacts. These modulating mechanisms are seldom measured and not fully understood. The impact of the warm 2012-15 California drought on the heavily instrumented Kings River basin provides an extraordinary opportunity to enumerate four mechanisms that controlled the impact of drought on mountain hydrology. Two mechanisms intensified the impact: (i) evaporative processes have first access to local precipitation, which decreased the fractional allocation of P to runoff in 2012-15 and reduced P-ET by 30% relative to previous years, and (ii) 2012-15 was 1 °C warmer than the previous decade, which increased ET relative to previous years and reduced P-ET by 5%. The other two mechanisms alleviated the impact: (iii) spatial heterogeneity and the continuing supply of runoff from higher elevations increased 2012-15 P-ET by 10% relative to that expected for a homogenous basin, and iv) drought-associated dieback and wildfire thinned the forest and decreased ET, which increased 2016 P-ET by 15%. These mechanisms are all important and may offset each other; analyses that neglect one or more will over or underestimate the impact of drought and warming on mountain runoff.

  11. The effect of natural weathering on the mechanical, morphological and thermal properties of high impact polystyrene (HIPS)

    International Nuclear Information System (INIS)

    Sahin, Tuelin; Sinmazcelik, Tamer; Sahin, Senol

    2007-01-01

    The effect of natural weathering on the mechanical, morphological and thermal properties on the high impact polystyrene (HIPS) and cold drawn HIPS are investigated. After natural weathering period of 8760 h, under known meteorological parameters, the changes in mechanical properties are investigated by using tensile, instrumented impact and hardness tests. Thermo-mechanical properties are characterized by using thermomechanical analysis (TMA) and melt flow index (MFI). Fractured surfaces of the materials are investigated by scanning electron microscope (SEM). Natural weathering effects on fracture mechanisms are discussed by means of fractographical analysis. Remarkable morphological changes were observed especially at the surface of the material. This results in dramatic loss in mechanical properties

  12. On impact mechanics in ship collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship–ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

  13. On Impact Mechanics in Ship Collisions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Zhang, Shengming

    1998-01-01

    The purpose of this paper is to present analytical, closed-form expressions for the energy released for crushing and the impact impulse during ship collisions. Ship-ship collisions, ship collisions with rigid walls and ship collisions with flexible offshore structures are considered. The derived ...

  14. Protection of mechanized timberings on beds dangerous for mine impacts

    Energy Technology Data Exchange (ETDEWEB)

    Budirsky, S

    1982-01-01

    In some stoping faces on beds which are dangerous for mine impacts, mechanized timbering is successfully used which is not equipped with protection from the effect of these dynamic phenomena. This generated the idea that in the indicated conditions, mechanized timbering may not be equipped with protective devices against dynamic loads. Theoretical studies have shown that the effects of mine impacts depends on the total energy of the impact, distance of this stoping face from the epicenter of the impact, as well as the capacity of the rock massif to transmit and absorb energy of the mine impact. This means that the effect of the mine impact under different conditions is not the same, the mine impacts of lower energy under definite conditions can result in greater damages to the mechanized timbering than mine impact with higher energy. It is believed that the effect of absorption of energy of the mine impact depends on the method of control of the roofing in the stoping face, the presence of hydraulic fill quarantees absorption of up to 80% of its energy. The experience of working beds which are dangerous for mine impacts in the upper Silesia coal basin indicated that the designs of the mechanized timbering, especially shield, in which the stands are not rigidly connected to the roof timber, during operation on beds with thickness 2.5-4 m withstand mine impacts with energy 10/sup 7/ J without significant disorders (mine impacts with this energy occur very frequently . For energy of mine impact of 108 J (impacts with this energy are observed comparatively rarely), the mechanized timberings are considerably damaged.

  15. Mechanical properties of glasses impacted by debris or micrometeorites

    Science.gov (United States)

    Kinser, Donald L.; Wiedlocher, David E.

    1992-01-01

    Mechanical strength measurements on five glasses and one glass ceramic exposed on the Long Duration Exposure Facility (LDEF) have revealed no damage exceeding experimental limits of error after exposure. The measurement technique subjected less than 5 percent of the sample surface area to stresses above 90 percent of the failure strength. Seven micrometeorite or space debris impacts occurred at locations which were not in that portion of the sample subjected to greater than 90 percent of the applied stress. In consequence of this, the impact events on the sample were not detected in mechanical strength measurements. The physical form and structure of the impact sites was carefully examined to determine the influence of those events upon stress concentration associated with the impact and the resulting mechanical strength influence. The size of the impact site insofar as it determines flaw size for fracture purposes was examined. Surface topography of the impacts reveals that six of the seven sites display impact melting. The classical melt crater structure is surrounded by a zone of fractured glass. Residual stresses arising from shock compression and from cooling of the impact fused zone cannot be included in fracture mechanics analyses based on simple flaw size analyses. Strategies for refining estimates of mechanical strength degradation by impact events are presented.

  16. BADMINTON TRAINING MACHINE WITH IMPACT MECHANISM

    Directory of Open Access Journals (Sweden)

    B. F. YOUSIF

    2011-02-01

    Full Text Available In the current work, a newly machine was designed and fabricated for badminton training purpose. In the designing process, CATIA software was used to design and simulate the machine components. The design was based on direct impact method to launch the shuttle using spring as the source of the impact. Hook’s law was used theoretically to determine the initial and the maximum lengths of the springs. The main feature of the machine is that can move in two axes (up and down, left and right. For the control system, infra-red sensor and touch switch were adapted in microcontroller. The final product was locally fabricated and proved that the machine can operate properly.

  17. Impact of and correction for instrument sensitivity drift on nanoparticle size measurements by single-particle ICP-MS

    Science.gov (United States)

    El Hadri, Hind; Petersen, Elijah J.; Winchester, Michael R.

    2016-01-01

    The effect of ICP-MS instrument sensitivity drift on the accuracy of NP size measurements using single particle (sp)ICP-MS is investigated. Theoretical modeling and experimental measurements of the impact of instrument sensitivity drift are in agreement and indicate that drift can impact the measured size of spherical NPs by up to 25 %. Given this substantial bias in the measured size, a method was developed using an internal standard to correct for the impact of drift and was shown to accurately correct for a decrease in instrument sensitivity of up to 50 % for 30 nm and 60 nm gold nanoparticles. PMID:26894759

  18. Vitiligo impact scale: An instrument to assess the psychosocial burden of vitiligo

    Directory of Open Access Journals (Sweden)

    Gaurang S Krishna

    2013-01-01

    Full Text Available Background : Vitiligo is a disease that significantly impairs quality of life. Previous studies have shown that vitiligo has an impact that may not correlate with the size and extent of depigmentation, indicating a need for an independent measure of the psychosocial burden. Aims : To develop a rating scale to assess the psychosocial impact of vitiligo. Methods : The study was undertaken in three broad phases: item generation, pre- and pilot testing, and test administration. Items were generated largely from a qualitative study using semi-structured interviews of patients. Face and content validity were assessed through pre- and pilot testing in 80 patients and the final version was administered to 100 patients who also received the Dermatology Life Quality Index (DLQI and the Skindex-16. Each patient also underwent a physician global assessment (PGA of the impact of vitiligo. Test-retest reliability was assessed in 20 patients. Results: Of 72 items initially generated for the scale, 27 were retained in the final version. Subjects were able to comprehend the items and took about 5-7 min to complete the instrument. The scale was internally consistent (Cronbach′s α = 0.85. Scores on the scale correlated moderately well with the DLQI and the Skindex (Spearman rank correlation: 0.51 and 0.65, respectively. The scale was able to discriminate between patients having mild and those having moderate and severe impact as assessed by PGA. The test-retest reliability coefficient (Spearman rank correlation was 0.80. Conclusion: The Vitiligo Impact Scale appears to be a valid measure of the psychosocial impact of vitiligo and this instrument may be useful both in the clinic and in clinical trials.

  19. Dynamic Analysis of Hammer Mechanism "Twin Hammer" of Impact Wrench

    Science.gov (United States)

    Konečný, M.; Slavík, J.

    This paper describes function of the hammer mechanism "Twin hammer" the impact wrench, calculation of dynamic forces exerted on the mechanism and determining the contact pressures between the parts of the mechanism. The modelling of parts was performed in system Pro ENGINEER—standard. The simulation and finding dynamic forces was performed in advanced module Pro ENGINEER—mechanism design and finding contacts pressures in modul Pro ENGENEER—mechanica.

  20. Leveraging non-binding instruments for global health governance: reflections from the Global AIDS Reporting Mechanism for WHO reform.

    Science.gov (United States)

    Taylor, A L; Alfven, T; Hougendobler, D; Tanaka, S; Buse, K

    2014-02-01

    As countries contend with an increasingly complex global environment with direct implications for population health, the international community is seeking novel mechanisms to incentivize coordinated national and international action towards shared health goals. Binding legal instruments have garnered increasing attention since the World Health Organization adopted its first convention in 2003. This paper seeks to expand the discourse on future global health lawmaking by exploring the potential value of non-binding instruments in global health governance, drawing on the case of the 2001 United Nations General Assembly Special Session Declaration of Commitment on HIV/AIDS. In other realms of international concern ranging from the environment to human rights to arms control, non-binding instruments are increasingly used as effective instruments of international cooperation. The experience of the Global AIDS Reporting Mechanism, established pursuant to the Declaration, evidences that, at times, non-binding legal instruments can offer benefits over slower, more rigid binding legal approaches to governance. The global AIDS response has demonstrated that the use of a non-binding instrument can be remarkably effective in galvanizing increasingly deep commitments, action, reporting compliance and ultimately accountability for results. Based on this case, the authors argued that non-binding instruments deserve serious consideration by the international community for the future of global health governance, including in the context of WHO reform. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  1. Manual and Instrument Applied Cervical Manipulation for Mechanical Neck Pain: A Randomized Controlled Trial.

    Science.gov (United States)

    Gorrell, Lindsay M; Beath, Kenneth; Engel, Roger M

    2016-06-01

    The purpose of this study was to compare the effects of 2 different cervical manipulation techniques for mechanical neck pain (MNP). Participants with MNP of at least 1 month's duration (n = 65) were randomly allocated to 3 groups: (1) stretching (control), (2) stretching plus manually applied manipulation (MAM), and (3) stretching plus instrument-applied manipulation (IAM). MAM consisted of a single high-velocity, low-amplitude cervical chiropractic manipulation, whereas IAM involved the application of a single cervical manipulation using an (Activator IV) adjusting instrument. Preintervention and postintervention measurements were taken of all outcomes measures. Pain was the primary outcome and was measured using visual analogue scale and pressure pain thresholds. Secondary outcomes included cervical range of motion, hand grip-strength, and wrist blood pressure. Follow-up subjective pain scores were obtained via telephone text message 7 days postintervention. Subjective pain scores decreased at 7-day follow-up in the MAM group compared with control (P = .015). Cervical rotation bilaterally (ipsilateral: P = .002; contralateral: P = .015) and lateral flexion on the contralateral side to manipulation (P = .001) increased following MAM. Hand grip-strength on the contralateral side to manipulation (P = .013) increased following IAM. No moderate or severe adverse events were reported. Mild adverse events were reported on 6 occasions (control, 4; MAM, 1; IAM, 1). This study demonstrates that a single cervical manipulation is capable of producing immediate and short-term benefits for MNP. The study also demonstrates that not all manipulative techniques have the same effect and that the differences may be mediated by neurological or biomechanical factors inherent to each technique. Copyright © 2016. Published by Elsevier Inc.

  2. Opto-mechanical design of optical window for aero-optics effect simulation instruments

    Science.gov (United States)

    Wang, Guo-ming; Dong, Dengfeng; Zhou, Weihu; Ming, Xing; Zhang, Yan

    2016-10-01

    A complete theory is established for opto-mechanical systems design of the window in this paper, which can make the design more rigorous .There are three steps about the design. First, the universal model of aerodynamic environment is established based on the theory of Computational Fluid Dynamics, and the pneumatic pressure distribution and temperature data of optical window surface is obtained when aircraft flies in 5-30km altitude, 0.5-3Ma speed and 0-30°angle of attack. The temperature and pressure distribution values for the maximum constraint is selected as the initial value of external conditions on the optical window surface. Then, the optical window and mechanical structure are designed, which is also divided into two parts: First, mechanical structure which meet requirements of the security and tightness is designed. Finally, rigorous analysis and evaluation are given about the structure of optics and mechanics we have designed. There are two parts to be analyzed. First, the Fluid-Solid-Heat Coupled Model is given based on finite element analysis. And the deformation of the glass and structure can be obtained by the model, which can assess the feasibility of the designed optical windows and ancillary structure; Second, the new optical surface is fitted by Zernike polynomials according to the deformation of the surface of the optical window, which can evaluate imaging quality impact of spectral camera by the deformation of window.

  3. Positive Impact of Art as a Communication Instrument on Economical Productivity

    Directory of Open Access Journals (Sweden)

    Sedat Cereci

    2013-08-01

    Full Text Available There are many factors that affect economical productivity like climate, or like raw materials or like international relationships or like physchology of employers. Professional organisations or companies use different instruments to increase producticity on economy. Spiritual conditions of employers and employees are especially regarded for economical productivity recently. Though economy is mostly a concrete area, main component of economy is human and human need spiritual support and impacts in his life. It is known that spiritual support always feed human and provide him much energy. Employers or companies who are interested in art and who participate in artistic activities become more productive than others and attract people to their productions.

  4. The practical impact of differential item functioning analyses in a health-related quality of life instrument

    DEFF Research Database (Denmark)

    Scott, Neil W; Fayers, Peter M; Aaronson, Neil K

    2009-01-01

    Differential item functioning (DIF) analyses are commonly used to evaluate health-related quality of life (HRQoL) instruments. There is, however, a lack of consensus as to how to assess the practical impact of statistically significant DIF results.......Differential item functioning (DIF) analyses are commonly used to evaluate health-related quality of life (HRQoL) instruments. There is, however, a lack of consensus as to how to assess the practical impact of statistically significant DIF results....

  5. Multi-Instrument Investigation of Ionospheric Flow Channels and Their Impact on the Ionosphere and Thermosphere during Geomagnetic Storms

    Science.gov (United States)

    2017-12-29

    AFRL-AFOSR-JP-TR-2018-0009 Multi-instrument investigation of ionospheric flow channels and their impact on the ionosphere and thermosphere during...SUBTITLE Multi-instrument investigation of ionospheric flow channels and their impact on the ionosphere and thermosphere during geomagnetic storms 5a...Experiment) and GOCE (Gravity field and steady- state Ocean Circulation Explorer) satellite data. We also created a series of computer algorithms to

  6. Algorithm of choosing type of mechanical assembly production of instrument making enterprises of Industry 4.0

    Science.gov (United States)

    Zakoldaev, D. A.; Shukalov, A. V.; Zharinov, I. O.; Zharinov, O. O.

    2018-05-01

    The task of the algorithm of choosing the type of mechanical assembly production of instrument making enterprises of Industry 4.0 is being studied. There is a comparison of two project algorithms for Industry 3.0 and Industry 4.0. The algorithm of choosing the type of mechanical assembly production of instrument making enterprises of Industry 4.0 is based on the technological route analysis of the manufacturing process in a company equipped with cyber and physical systems. This algorithm may give some project solutions selected from the primary part or the auxiliary one of the production. The algorithm decisive rules are based on the optimal criterion.

  7. Mechanical and geometric features of endodontic instruments and its clinical effect

    Directory of Open Access Journals (Sweden)

    Hyeon-Cheol Kim

    2011-01-01

    Full Text Available Introduction The aim of this paper is to discuss the mechanical and geometric features of Nickel-titanium (NiTi rotary files and its clinical effects. NiTi rotary files have been introduced to the markets with their own geometries and claims that they have better ability for the root canal shaping than their competitors. The contents of this paper include the (possible interrelationship between the geometries of NiTi file (eg. tip, taper, helical angle, etc and clinical performance of the files as follows; - Fracture modes of NiTi rotary files - Non-cutting guiding tip and glide path - Taper and clinical effects - Cross-sectional area and clinical effects - Heat treatments and surface characteristics - Screw-in effect and preservation of root dentin integrity - Designs for reducing screw-in effect Conclusions Based on the reviewed contents, clinicians may have an advice to use various brands of NiTi rotary instruments regarding their advantages which would fit for clinical situation.

  8. Psychometric Evaluation of an Adolescent and Young Adult Module of the Impact of Cancer Instrument.

    Science.gov (United States)

    Husson, Olga; Zebrack, Bradley J

    2017-03-01

    To develop and evaluate a new instrument that measures unique aspects of long-term survivorship for people diagnosed with cancer as Adolescent and Young Adult (AYA), not measured by existing tools. A new candidate instrument-the Impact of Cancer for Adolescent and Young Adult (IOC-AYA) cancer survivors-was developed and administered to AYA cancer survivors aged 18-35 years who were 15-29 years old when diagnosed with cancer. Psychometric properties of newly derived scales were assessed. Factor analyses of items derived seven new and specific subscales: Social Life; Uncertainties, Worries and Wonders; Cognitive Function; Sense of Purpose/Life Goals; Identity; Health Behaviors; and Health Literacy. Two separate and conditional subscales were formed: Relationship Concerns (partnered/unpartnered) and Having Children (at least one child/no children). Internal consistency measurements for these subscales ranged from 0.70 to 0.90. Expected associations within and among IOC-AYA subscales and standardized measures of quality of life were observed. Psychometric analyses indicated that this initial version of the IOC-AYA measures distinct and relevant constructs for survivors diagnosed with cancer in adolescence and young adulthood. Future work is needed to confirm the responsiveness to change and further validate the instrument in multiple and representative samples. Use of the IOC-AYA instrument in research and clinical practice will inform the development of psychosocial and supportive care interventions that not only minimize or prevent long-term deleterious effects of cancer but also promote positive adaptation, resilience, and the achievement of age-specific developmental tasks.

  9. Impact of Financing Instruments and Strategies on the Wind Power Production Costs: A Case of Lithuania

    Science.gov (United States)

    Bobinaite, V.; Konstantinaviciute, I.

    2018-04-01

    The paper aims at demonstrating the relevance of financing instruments, their terms and financing strategies in relation to the cost of wind power production and the ability of wind power plant (PP) to participate in the electricity market in Lithuania. The extended approach to the Levelized Cost of Energy (LCOE) is applied. The feature of the extended approach lies in considering the lifetime cost and revenue received from the support measures. The research results have substantiated the relevance of financing instruments, their terms and strategies in relation to their impact on the LCOE and competitiveness of wind PP. It has been found that financing of wind PP through the traditional financing instruments (simple shares and bank loans) makes use of venture capital and bonds coming even in the absence of any support. It has been estimated that strategies consisting of different proportions of hard and soft loans, bonds, own and venture capital result in the average LCOE of 5.1-5.7 EURct/kWh (2000 kW), when the expected electricity selling price is 5.4 EURct/kWh. The financing strategies with higher shares of equity could impact by around 6 % higher LCOE compared to the strategies encompassing higher shares of debt. However, seeking to motivate venture capitalists, bond holders or other new financiers entering the wind power sector, support measures (feed-in tariff or investment subsidy) are relevant in case of 250 kW wind PP. It has been estimated that under the unsupported financing strategies, the average LCOE of 250 kW wind PP will be 7.8-8.8 EURct/kWh, but it will reduce by around 50 % if feed-in tariff or 50 % investment subsidy is applied.

  10. Mechanical properties of ProTaper Gold nickel-titanium rotary instruments.

    Science.gov (United States)

    Elnaghy, A M; Elsaka, S E

    2016-11-01

    To evaluate and compare the resistance to cyclic fatigue and torsional stress, flexibility and surface microhardness of ProTaper Gold (PTG; Dentsply, Tulsa Dental Specialties, Tulsa, OK, USA) system with ProTaper Universal (PTU; Dentsply Maillefer, Ballaigues, Switzerland). PTG and PTU instruments were rotated in simulated canals and the number of cycles to failure was recorded to assess their cyclic fatigue resistance. Torsional strength was measured using a torsiometer after fixing firmly the apical 3 mm of the instrument. A scanning electron microscope was used to characterize the topographic features of the fracture surfaces of the broken instruments. The instruments were tested for bending resistance using cantilever-bending test. Vickers microhardness was measured on the cross section of instruments with 300 g load and 15 s dwell time. Data were analysed statistically using independent t-tests. Statistical significance was set at P hand, PTU instruments were associated with higher resistance to torsional stress and microhardness than PTG instruments (P < 0.001). After torsional tests, the fractured cross-sectional surfaces revealed skewed dimples near the centre of the fracture surfaces and circular abrasion streaks. The PTG instrument had improved resistance to cyclic fatigue and flexibility compared with PTU. PTU instruments had improved resistance to torsional stress and microhardness compared with PTG. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  11. Impact mechanics of the Cretaceous-Tertiary extinction bolide

    Science.gov (United States)

    Okeefe, J. D.; Ahrens, T. J.

    1982-01-01

    An examination of the mechanics of asteroidal, cometary, and meteor swarm impact on the earth determined if the enrichment of projectile material in the K-T layer is consistent with melts and impact breccias on the earth and moon, the size of the impacters, the distribution of the kinetic energy, and the sequence of impacts that could give rise to observed extinction phenomena. Flows resulting from spherical projectile impacts onto layers of air, water, and silicates were modeled and Eulerian finite difference algorithms were employed to solve conservation equations and equations of state. A range of speeds and impacter densities were considered, along with sizes from 0.17 km, which would be consumed in the atmosphere, to a 10 km object, which would have had a diameter greater than a reference 7.1 km atmosphere depth. It is concluded that an impact of the K-T bolide could result in global biotic extinction and worldwide material deposition.

  12. Environmental impact assessment (EIA): an overlooked instrument for sustainable development in Pakistan.

    Science.gov (United States)

    Saeed, Rashid; Sattar, Ayesha; Iqbal, Zafar; Imran, Muhammad; Nadeem, Raziya

    2012-04-01

    Environmental impact assessment (EIA) is a policy tool used for evaluating a project proposal from physical and socioeconomic environmental perspectives. Its aim is to reduce the impact of development on environment, hence, ensuring environmental sustainability. It is mandatory to submit an Environmental Impact Statement before starting a mega project as required by Environmental Protection Act of 1997 and Environmental Policy of Pakistan. Public consultation plays a key role in an EIA system, identifying the likely aspects and impacts of a development activity. This aspect has been ignored in effective enactment of environmental legislation in Pakistan. Sufficient legislative instruments are there to support EIA system in the country but the agencies responsible for the enforcement of environmental regulations have failed to do so. The current research gives an insight into the actual status of EIA system in Pakistan along with the feedback of EIA specialists and university teachers of the concerned departments. A new index has been devised on the basis of questionnaire response to work out the overall performance of EIA system in Pakistan or any other country. The weaknesses and deficiencies of each EIA stage have been worked out for Pakistan and elaborated with the help of the controversial Zero point Interchange Project in the capital city of Pakistan.

  13. Study on Mechanical Properties of Barite Concrete under Impact Load

    Science.gov (United States)

    Chen, Z. F.; Cheng, K.; Wu, D.; Gan, Y. C.; Tao, Q. W.

    2018-03-01

    In order to research the mechanical properties of Barite concrete under impact load, a group of concrete compression tests was carried out under the impact load by using the drop test machine. A high-speed camera was used to record the failure process of the specimen during the impact process. The test results show that:with the increase of drop height, the loading rate, the peak load, the strain under peak load, the strain rate and the dynamic increase factor (DIF) all increase gradually. The ultimate tensile strain is close to each other, and the time of impact force decreases significantly, showing significant strain rate effect.

  14. Instrumented impact properties of zircaloy-oxygen and zircaloy-hydrogen alloys

    Energy Technology Data Exchange (ETDEWEB)

    Garde, A.M.; Kassner, T.F.

    1980-04-01

    Instrumented-impact tests were performed on subsize Charpy speciments of Zircaloy-2 and -4 with up to approx. 1.3 wt % oxygen and approx. 2500 wt ppM hydrogen at temperatures between 373 and 823/sup 0/K. Self-consistent criteria for the ductile-to-brittle transition, based upon a total absorbed energy of approx. 1.3 x 10/sup 4/ J/m/sup 2/, a dynamic fracture toughness of approx. 10 MPa.m/sup 1/2/, and a ductility index of approx. 0, were established relative to the temperature and oxygen concentration of the transformed BETA-phase material. The effect of hydrogen concentration and hydride morphology, produced by cooling Zircaloy-2 specimens through the temperature range of the BETA ..-->.. ..cap alpha..' = hydride phase transformation at approx. 0.3 and 3 K/s, on the impact properties was determined at temperatures between 373 and 673 K. On an atom fraction basis, oxygen has a greater effect than hydrogen on the impact properties of Zircaloy at temperatures between approx. 400 and 600 K. 34 figures.

  15. The impact of instrumental feeding on children's responses to taste exposure.

    Science.gov (United States)

    Añez, E; Remington, A; Wardle, J; Cooke, L

    2013-10-01

    In a recent study, we showed that nonfood incentives combined with taste exposure increase children's acceptance of vegetables. However, the impact of children's previous experience of receiving food rewards is unknown. The present study investigated whether the experience of food rewards affects responses to an exposure-plus-reward intervention. One hundred and thirty-seven parents of 4-6-year-old children taking part in an exposure-based intervention study completed an instrumental feeding (IF) questionnaire aiming to assess their use of food rewards. Based on these scores, children were categorised as frequently or rarely instrumentally-fed. Intervention groups were given 12 daily tastes of a target vegetable combined with no reward, a tangible reward, (sticker) or a verbal reward (praise). A no-treatment control group received no tastings. Liking and intake of a target vegetable were measured at baseline and post-intervention. Irrespective of experience of IF, children in all intervention groups increased liking compared to controls (all P exposure group, only children with a limited experience with food rewards increased consumption (P mere exposure'. However, exposure with nonfood rewards can increase the acceptance of vegetables, regardless of previous experience. © 2012 The Authors Journal of Human Nutrition and Dietetics © 2012 The British Dietetic Association Ltd.

  16. Novel instrument for characterizing comprehensive physical properties under multi-mechanical loads and multi-physical field coupling conditions

    Science.gov (United States)

    Liu, Changyi; Zhao, Hongwei; Ma, Zhichao; Qiao, Yuansen; Hong, Kun; Ren, Zhuang; Zhang, Jianhai; Pei, Yongmao; Ren, Luquan

    2018-02-01

    Functional materials represented by ferromagnetics and ferroelectrics are widely used in advanced sensor and precision actuation due to their special characterization under coupling interactions of complex loads and external physical fields. However, the conventional devices for material characterization can only provide a limited type of loads and physical fields and cannot simulate the actual service conditions of materials. A multi-field coupling instrument for characterization has been designed and implemented to overcome this barrier and measure the comprehensive physical properties under complex service conditions. The testing forms include tension, compression, bending, torsion, and fatigue in mechanical loads, as well as different external physical fields, including electric, magnetic, and thermal fields. In order to offer a variety of information to reveal mechanical damage or deformation forms, a series of measurement methods at the microscale are integrated with the instrument including an indentation unit and in situ microimaging module. Finally, several coupling experiments which cover all the loading and measurement functions of the instrument have been implemented. The results illustrate the functions and characteristics of the instrument and then reveal the variety in mechanical and electromagnetic properties of the piezoelectric transducer ceramic, TbDyFe alloy, and carbon fiber reinforced polymer under coupling conditions.

  17. Mechanical, electronic and instrumentation development for tracer tests at El Berrocal site

    International Nuclear Information System (INIS)

    Gutierrez, M.G.; Benitez, A.H.; Yllera de Llano, A.; Romero, P.R.; Aleixandre, J.; Bueno, J.; Gonzalez, O.; Tamarit, J.; Guimera, J.

    1997-01-01

    The international El Berrocal Project was an integrated exercise in geological, geochemical and hydrogeological characterization with the aim of understanding and modelling the past and present-day migration processes that control the behaviour and distribution of naturally occurring radionuclides in a fractured granitic environment. Information is presented concerning the design and manufacture of the instrumentation used for the large scale tracer tests performed at El Berrocal, and the instrumentation and data acquisition development is specified. (author)

  18. Woodfuel in Rwanda: Impact on Energy, Poverty, Environment and Policy Instruments analysis

    Directory of Open Access Journals (Sweden)

    Ernest Mazimpaka

    2014-02-01

    Full Text Available Rwanda’s geographical and socio-economic situations have shaped the energy situation and limited access to modern fuels. Woodfuel is the main source of energy for households and its trade a source of income and jobs in rural areas. Currently 85.2% of households’ land holding is less than 1 ha, insufficient to grow food and fuelwood for a household of the average size of 5.5 persons. Without well documented reports of the individual impact of each deforestation factor, woodfuels have been most blamed. This paper investigates how the current woodfuel industry impacts on energy, poverty and forests and analyses the woodfuel policy instruments. Considering woodfuel consumption under an only environmental or energy perspective has resulted in a search for a narrowly environmental or energy solution. Both failed to solve the problem of forest depletion. Current regulations limit the benefits traditionally derived from woodfuel commoditisation leading to a negative attitude towards policy instruments. The processes involved in producing charcoal and using it as a cooking fuel is inefficient and resource intensive. The barriers to large dissemination of improved cooking stoves include availability, relatively low cost of woodfuels, lack of improved stove diversity on the local market and weak government policy in regard to the woodfuel industry. Policies aiming to substitute or reduce woodfuel consumption, have not achieved the desired results and their implementations have not unarguably reduced deforestation. The paper recommends the community-based woodfuel production as sustainable management approaches to mobilise community support for sustainable forestry management and woodfuel production.

  19. Synchronization of impacting mechanical systems with a single constraint

    Science.gov (United States)

    Baumann, Michael; Biemond, J. J. Benjamin; Leine, Remco I.; van de Wouw, Nathan

    2018-01-01

    This paper addresses the synchronization problem of mechanical systems subjected to a single geometric unilateral constraint. The impacts of the individual systems, induced by the unilateral constraint, generally do not coincide even if the solutions are arbitrarily 'close' to each other. The mismatch in the impact time instants demands a careful choice of the distance function to allow for an intuitively correct comparison of the discontinuous solutions resulting from the impacts. We propose a distance function induced by the quotient metric, which is based on an equivalence relation using the impact map. The distance function obtained in this way is continuous in time when evaluated along jumping solutions. The property of maximal monotonicity, which is fulfilled by most commonly used impact laws, is used to significantly reduce the complexity of the distance function. Based on the simplified distance function, a Lyapunov function is constructed to investigate the synchronization problem for two identical one-dimensional mechanical systems. Sufficient conditions for the uncoupled individual systems are provided under which local synchronization is guaranteed. Furthermore, we present an interaction law which ensures global synchronization, also in the presence of grazing trajectories and accumulation points (Zeno behavior). The results are illustrated using numerical examples of a 1-DOF mechanical impact oscillator which serves as stepping stone in the direction of more general systems.

  20. On the validity of Ksub(Id)-measurements in instrumented impact tests

    International Nuclear Information System (INIS)

    Kalthoff, J.F.; Winkler, S.; Klemm, W.; Beinert, J.

    1979-01-01

    The influence of inertia effects in determining the dynamic fracture toughness Ksub(Id) by instrumented impact testing is investigated. Model experiments in the brittle fracture regime are carried out with precracked bend specimens machined from the epoxy resin Araldite B. As is usual in these tests, the loads at the tup of the impinging striker are recorded as a function of time during the impact process. For reference purposes, the dynamic fracture toughness value Ksub(Id)sup(m1) is derived from the measured maximum load utilizing static stress intensity factor formulas. In addition to this conventional procedure, the actual stress intensity factors are measured directly at the tip of the crack by means of the shadow optical method of caustics applied in combination with high speed photography. The critical value of these optically measured stress intensity factors (for onset of crack propagation), Ksub(Id)sup(opt), is the true dynamic fracture toughness. In the experiments, the specimen size and the impact velocity were varied. In accordance with expectations, it is found that the hammer load signal is not correlated with the actual crack tip stress intensity factor values by a simple proportionality. The conventionally determined Ksub(Id)sup(m1)-value overestimates the true dynamic fracture toughness Ksub(Id)sup(opt). This overestimation becomes larger for larger specimen sizes and larger impact velocities. The results demonstrate the dominating influence inertia effects can have on hammer load measurements and emphasize the importance of eliminating these effects in order to determine non-erroneous dynamic fracture toughness values. (orig.)

  1. The Project Based Mechanisms of the Kyoto Protocol. Credible Instruments or Challenges to the Integrity of the Kyoto Protocol?

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi Waldegren, Linn

    2006-03-15

    The project based mechanisms of the Kyoto Protocol are innovative instruments which allow projects to earn credits for reducing greenhouse gas (GHG) emissions. The credits can in turn be used by countries to reach their emissions targets according to the Kyoto Protocol. The Project based mechanisms are known as the Clean Development Mechanism (CDM) and the Joint Implementation (JI). If the project based mechanisms are to be effective policy instruments they must ensure the integrity of the Kyoto Protocol, and their ability to promote and prove real emission reductions is critical. The environmental credibility of the project based mechanisms will also ensure their ability to promote cost effectiveness. Key concepts in this context are environmental and project additionality, and their role and value for the project based mechanisms are analyzed. Environmental additionality is established by comparing a project's emissions to a baseline. The baseline's credibility is thus vital. The concept of project additionality is somewhat controversial, but is nonetheless of equal importance. The case studies of CDM approved methodologies (AMs) and proposed projects suggest that there are credibility issues that need to be addressed if the project based mechanisms are to promote real emissions reductions.

  2. CDM (Clean development mechanism) like instrument for sustainable development?; MDL (mecanismo de desenvolvimento limpo) como instrumento para o desenvolvimento sustentavel?

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Kamyla Borges da; Walter, Arnaldo Cesar Silva; Varella, Fabiana Karla de Oliveira; Streb, Cleci Schalemberger [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Fac. de Engenharia Mecanica. Curso de Pos-Graduaco em Planejamento de Sistemas Energeticos], e-mail: kamyla@fem.unicamp.br

    2004-07-01

    The intensification of the greenhouse effect, caused mainly by the anthropogenic activities, such as the intensive use of fossil fuels, reveals itself as a challenge to governments and international organizations. The institution of an international legal framework, resulted from the implementation of the United Nations Framework Convention on Climate Change and the Kyoto Protocol, is allowing the development of some mitigation instruments, such as the clean development mechanism (CDM). The article's purpose is to assess the social and economic aspects that are leading to the climate change process and to analyze the instruments foreseen in the international legal system to face this global concern, in special, the CDM as a tool to achieve sustainable development practices. In this way, the authors aims to demonstrate the connection and interdependence between those instruments and the sustainable development. (author)

  3. CDM (Clean development mechanism) like instrument for sustainable development?; MDL (mecanismo de desenvolvimento limpo) como instrumento para o desenvolvimento sustentavel?

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Kamyla Borges da; Walter, Arnaldo Cesar Silva; Varella, Fabiana Karla de Oliveira; Streb, Cleci Schalemberger [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Fac. de Engenharia Mecanica. Curso de Pos-Graduaco em Planejamento de Sistemas Energeticos], e-mail: kamyla@fem.unicamp.br

    2004-07-01

    The intensification of the greenhouse effect, caused mainly by the anthropogenic activities, such as the intensive use of fossil fuels, reveals itself as a challenge to governments and international organizations. The institution of an international legal framework, resulted from the implementation of the United Nations Framework Convention on Climate Change and the Kyoto Protocol, is allowing the development of some mitigation instruments, such as the clean development mechanism (CDM). The article's purpose is to assess the social and economic aspects that are leading to the climate change process and to analyze the instruments foreseen in the international legal system to face this global concern, in special, the CDM as a tool to achieve sustainable development practices. In this way, the authors aims to demonstrate the connection and interdependence between those instruments and the sustainable development. (author)

  4. Development and Preliminary Testing of a High Precision Long Stroke Slit Change Mechanism for the SPICE Instrument

    Science.gov (United States)

    Paciotti, Gabriel; Humphries, Martin; Rottmeier, Fabrice; Blecha, Luc

    2014-01-01

    In the frame of ESA's Solar Orbiter scientific mission, Almatech has been selected to design, develop and test the Slit Change Mechanism of the SPICE (SPectral Imaging of the Coronal Environment) instrument. In order to guaranty optical cleanliness level while fulfilling stringent positioning accuracies and repeatability requirements for slit positioning in the optical path of the instrument, a linear guiding system based on a double flexible blade arrangement has been selected. The four different slits to be used for the SPICE instrument resulted in a total stroke of 16.5 mm in this linear slit changer arrangement. The combination of long stroke and high precision positioning requirements has been identified as the main design challenge to be validated through breadboard models testing. This paper presents the development of SPICE's Slit Change Mechanism (SCM) and the two-step validation tests successfully performed on breadboard models of its flexible blade support system. The validation test results have demonstrated the full adequacy of the flexible blade guiding system implemented in SPICE's Slit Change Mechanism in a stand-alone configuration. Further breadboard test results, studying the influence of the compliant connection to the SCM linear actuator on an enhanced flexible guiding system design have shown significant enhancements in the positioning accuracy and repeatability of the selected flexible guiding system. Preliminary evaluation of the linear actuator design, including a detailed tolerance analyses, has shown the suitability of this satellite roller screw based mechanism for the actuation of the tested flexible guiding system and compliant connection. The presented development and preliminary testing of the high-precision long-stroke Slit Change Mechanism for the SPICE Instrument are considered fully successful such that future tests considering the full Slit Change Mechanism can be performed, with the gained confidence, directly on a

  5. 'Mechanical restraint-confounders, risk, alliance score': testing the clinical validity of a new risk assessment instrument.

    Science.gov (United States)

    Deichmann Nielsen, Lea; Bech, Per; Hounsgaard, Lise; Alkier Gildberg, Frederik

    2017-08-01

    Unstructured risk assessment, as well as confounders (underlying reasons for the patient's risk behaviour and alliance), risk behaviour, and parameters of alliance, have been identified as factors that prolong the duration of mechanical restraint among forensic mental health inpatients. To clinically validate a new, structured short-term risk assessment instrument called the Mechanical Restraint-Confounders, Risk, Alliance Score (MR-CRAS), with the intended purpose of supporting the clinicians' observation and assessment of the patient's readiness to be released from mechanical restraint. The content and layout of MR-CRAS and its user manual were evaluated using face validation by forensic mental health clinicians, content validation by an expert panel, and pilot testing within two, closed forensic mental health inpatient units. The three sub-scales (Confounders, Risk, and a parameter of Alliance) showed excellent content validity. The clinical validations also showed that MR-CRAS was perceived and experienced as a comprehensible, relevant, comprehensive, and useable risk assessment instrument. MR-CRAS contains 18 clinically valid items, and the instrument can be used to support the clinical decision-making regarding the possibility of releasing the patient from mechanical restraint. The present three studies have clinically validated a short MR-CRAS scale that is currently being psychometrically tested in a larger study.

  6. Chaotic mechanics in systems with impacts and friction

    CERN Document Server

    Blazejczyk-Okolewska, Barbara; Kapitaniak, Tomasz; Wojewoda, Jerzy

    1999-01-01

    This book is devoted to the theory of chaotic oscillations in mechanical systems. Detailed descriptions of the basic types of nonlinearity - impacts and dry friction - are presented. The properties of such behavior are discussed, and the numerical and experimental results obtained by the authors are presented.The dynamic properties of systems described here can be useful in the proper design and use of mechanics where such behavior still creates problems.This book will be very useful for anyone with a fundamental knowledge of nonlinear mechanics who is beginning research in the field.

  7. Should different impact assessment instruments be integrated? Evidence from English spatial planning

    International Nuclear Information System (INIS)

    Tajima, Ryo; Fischer, Thomas B.

    2013-01-01

    This paper aims at providing empirical evidence to the question as to whether integration of different instruments is achieving its aim in supporting sustainable decision making, focusing on SEA inclusive sustainability appraisal (SA) and other impact assessments (IAs) currently used in English spatial planning. Usage of IAs in addition to SA is established and an analysis of the integration approach (in terms of process, output, and assessor) as well as its effectiveness is conducted. It is found that while integration enhances effectiveness to some extent, too much integration, especially in terms of the procedural element, appears to diminish the overall effectiveness of each IA in influencing decisions as they become captured by the balancing function of SA. -- Highlights: ► The usage of different impact assessments in English spatial planning is clarified. ► The relationship between integration approach and effectiveness is analyzed. ► Results suggest that integration does not necessarily lead to more sustainable decisions. ► Careful consideration is recommended upon process integration

  8. Should different impact assessment instruments be integrated? Evidence from English spatial planning

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Ryo, E-mail: tajima.ryo@nies.go.jp [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259-G5-9 Nagatsuta-cho, Midori-ku, Yokoyama City, Kanagawa, 226-8502 (Japan); Fischer, Thomas B., E-mail: fischer@liverpool.ac.uk [Department of Geography and Planning, School of Environmental Sciences, University of Liverpool, 74 Bedford Street South, Liverpool L69 7ZQ (United Kingdom)

    2013-07-15

    This paper aims at providing empirical evidence to the question as to whether integration of different instruments is achieving its aim in supporting sustainable decision making, focusing on SEA inclusive sustainability appraisal (SA) and other impact assessments (IAs) currently used in English spatial planning. Usage of IAs in addition to SA is established and an analysis of the integration approach (in terms of process, output, and assessor) as well as its effectiveness is conducted. It is found that while integration enhances effectiveness to some extent, too much integration, especially in terms of the procedural element, appears to diminish the overall effectiveness of each IA in influencing decisions as they become captured by the balancing function of SA. -- Highlights: ► The usage of different impact assessments in English spatial planning is clarified. ► The relationship between integration approach and effectiveness is analyzed. ► Results suggest that integration does not necessarily lead to more sustainable decisions. ► Careful consideration is recommended upon process integration.

  9. A mechanical protocol to replicate impact in walking footwear.

    Science.gov (United States)

    Price, Carina; Cooper, Glen; Graham-Smith, Philip; Jones, Richard

    2014-01-01

    Impact testing is undertaken to quantify the shock absorption characteristics of footwear. The current widely reported mechanical testing method mimics the heel impact in running and therefore applies excessive energy to walking footwear. The purpose of this study was to modify the ASTM protocol F1614 (Procedure A) to better represent walking gait. This was achieved by collecting kinematic and kinetic data while participants walked in four different styles of walking footwear (trainer, oxford shoe, flip-flop and triple-density sandal). The quantified heel-velocity and effective mass at ground-impact were then replicated in a mechanical protocol. The kinematic data identified different impact characteristics in the footwear styles. Significantly faster heel velocity towards the floor was recorded walking in the toe-post sandals (flip-flop and triple-density sandal) compared with other conditions (e.g. flip-flop: 0.36±0.05 ms(-1) versus trainer: 0.18±0.06 ms(-1)). The mechanical protocol was adapted by altering the mass and drop height specific to the data captured for each shoe (e.g. flip-flop: drop height 7 mm, mass 16.2 kg). As expected, the adapted mechanical protocol produced significantly lower peak force and accelerometer values than the ASTM protocol (pfootwear style specific. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Mechanical design and vibro-acoustic testing of ultrathin carbon foils for a spacecraft instrument

    Energy Technology Data Exchange (ETDEWEB)

    Bernardin, John D [Los Alamos National Laboratory; Baca, Allen G [SNL

    2009-01-01

    IBEX-Hi is an electrostatic analyzer spacecraft instrument designed to measure the energy and flux distribution of energetic neutral atoms (ENAs) emanating from the interaction zone between the Earth's solar system and the Milky Way galaxy. A key element to this electro-optic instrument is an array of fourteen carbon foils that are used to ionize the ENAs. The foils are comprised of an ultrathin (50-100 {angstrom} thick) layer of carbon suspended across the surface of an electroformed Nickel wire screen, which in turn is held taught by a metal frame holder. The electro formed orthogonal screen has square wire elements, 12.7 {micro}m thick, with a pitch of 131.1 wires/cm. Each foil holder has an open aperture approximately 5 cm by 2.5 cm. Designing and implementing foil holders with such a large surface area has not been attempted for spaceflight in the past and has proven to be extremely challenging. The delicate carbon foils are subject to fatigue failure from the large acoustic and vibration loads that they will be exposed to during launch of the spacecraft. This paper describes the evolution of the foil holder design from previous space instrument applications to a flight-like IBEX-Hi prototype. Vibro-acoustic qualification tests of the IBEX-Hi prototype instrument and the resulting failure of several foils are summarized. This is followed by a discussion of iterative foil holder design modifications and laser vibrometer modal testing to support future fatigue failure analyses, along with additional acoustic testing of the IBEX-Hi prototype instrument. The results of these design and testing activities are merged and the resulting flight-like foil holder assembly is proposed.

  11. Impact of state-of-the-art instrumentation on safety-related experimental studies proposed in containment studies facility (CSF)

    International Nuclear Information System (INIS)

    Gole, N.V.; Markandeya, S.G.; Subramaniam, K.; Ghosh, A.K.

    2002-01-01

    Full text: Conducting an experimental program for safety related studies for nuclear power plants (NPPs) is an extremely laborious and time-consuming task due to several reasons. Requirement for frequent replacements, testing and recalibration of a large number of instruments is one of them. Off-line analysis leading to identification of errors is another. A particular test may have to be abandoned based on such analysis. Following the rapid advances in instrumentation, a larger number of options are now available, which make experimentation easy. CSF is one of the upcoming facilities wherein deployment of state-of-the art became inevitable. This paper discusses in detail the design intent of instrumentation, the state-of-the-art instrumentation provisions made to fulfill it the overall impact of this on successful experimentation

  12. Analysis of the degradation mechanisms in an impacted ceramic

    International Nuclear Information System (INIS)

    Denoual, C.; Cottenot, C. E.; Hild, F.

    1998-01-01

    To analyze the degradation mechanisms in a natural sintered SiC (SSiC) ceramic during impact, three edge-on impact configurations are considered. First, the ceramic is confined by aluminum to allow a post-mortem analysis. In the second configuration, a polished surface of the ceramic is observed each micro-second by a high-speed camera to follow the damage generation and evolution. The third configuration uses a high-speed Moire photography system to measure dynamic 2-D strain fields. Sequences of fringe patterns are analyzed

  13. Mechanism of an acoustic wave impact on steel during solidification

    Directory of Open Access Journals (Sweden)

    K. Nowacki

    2013-04-01

    Full Text Available Acoustic steel processing in an ingot mould may be the final stage in the process of quality improvement of a steel ingot. The impact of radiation and cavitation pressure as well as the phenomena related to the acoustic wave being emitted and delivered to liquid steel affect various aspects including the internal structure fragmentation, rigidity or density of steel. The article provides an analysis of the mechanism of impact of physical phenomena caused by an acoustic wave affecting the quality of a steel ingot.

  14. Evaluating the Impact of Radio Frequency Identification Retained Surgical Instruments Tracking on Patient Safety: Literature Review.

    Science.gov (United States)

    Schnock, Kumiko O; Biggs, Bonnie; Fladger, Anne; Bates, David W; Rozenblum, Ronen

    2017-02-22

    Retained surgical instruments (RSI) are one of the most serious preventable complications in operating room settings, potentially leading to profound adverse effects for patients, as well as costly legal and financial consequences for hospitals. Safety measures to eliminate RSIs have been widely adopted in the United States and abroad, but despite widespread efforts, medical errors with RSI have not been eliminated. Through a systematic review of recent studies, we aimed to identify the impact of radio frequency identification (RFID) technology on reducing RSI errors and improving patient safety. A literature search on the effects of RFID technology on RSI error reduction was conducted in PubMed and CINAHL (2000-2016). Relevant articles were selected and reviewed by 4 researchers. After the literature search, 385 articles were identified and the full texts of the 88 articles were assessed for eligibility. Of these, 5 articles were included to evaluate the benefits and drawbacks of using RFID for preventing RSI-related errors. The use of RFID resulted in rapid detection of RSI through body tissue with high accuracy rates, reducing risk of counting errors and improving workflow. Based on the existing literature, RFID technology seems to have the potential to substantially improve patient safety by reducing RSI errors, although the body of evidence is currently limited. Better designed research studies are needed to get a clear understanding of this domain and to find new opportunities to use this technology and improve patient safety.

  15. Neighborhood Poverty Impacts Children's Physical Health and Well-Being over Time: Evidence from the Early Development Instrument

    Science.gov (United States)

    Cushon, Jennifer A.; Vu, Lan T. H.; Janzen, Bonnie L.; Muhajarine, Nazeem

    2011-01-01

    Research Findings: The purpose of this study was to investigate how neighborhoods and neighborhood socioeconomic disadvantage impact school readiness over time. School readiness was measured using the Early Development Instrument (EDI) for 3 populations of kindergartners in 2001, 2003, and 2005 in Saskatoon, Saskatchewan, Canada. EDI results…

  16. Applications of Laminar Weak-Link Mechanisms for Ultraprecision Synchrotron Radiation Instruments

    International Nuclear Information System (INIS)

    Shu, D.; Toellner, T. S.; Alp, E. E.; Maser, J.; Ilavsky, J.; Shastri, S. D.; Lee, P. L.; Narayanan, S.; Long, G. G.

    2007-01-01

    Unlike traditional kinematic flexure mechanisms, laminar overconstrained weak-link mechanisms provide much higher structure stiffness and stability. Using a laminar structure configured and manufactured by chemical etching and lithography techniques, we are able to design and build linear and rotary weak-link mechanisms with ultrahigh positioning sensitivity and stability for synchrotron radiation applications. Applications of laminar rotary weak-link mechanism include: high-energy-resolution monochromators for inelastic x-ray scattering and x-ray analyzers for ultra-small-angle scattering and powder-diffraction experiments. Applications of laminar linear weak-link mechanism include high-stiffness piezo-driven stages with subnanometer resolution for an x-ray microscope. In this paper, we summarize the recent designs and applications of the laminar weak-link mechanisms at the Advanced Photon Source

  17. Mechanical properties and impact behavior of a microcellular structural foam

    Directory of Open Access Journals (Sweden)

    M. Avalle

    Full Text Available Structural foams are a relatively new class of materials with peculiar characteristics that make them very attractive in some energy absorption applications. They are currently used for packaging to protect goods from damage during transportation in the case of accidental impacts. Structural foams, in fact, have sufficient mechanical strength even with reduced weight: the balance between the two antagonist requirements demonstrates that these materials are profitable. Structural foams are generally made of microcellular materials, obtained by polymers where voids at the microscopic level are created. Although the processing technologies and some of the material properties, including mechanical, are well known, very little is established for what concerns dynamic impact properties, for the design of energy absorbing components made of microcellular foams. The paper reports a number of experimental results, in different loading conditions and loading speed, which will be a basis for the structural modeling.

  18. Characterization of Thermal and Mechanical Impact on Aluminum Honeycomb Structures

    Science.gov (United States)

    Robinson, Christen M.

    2013-01-01

    This study supports NASA Kennedy Space Center's research in the area of intelligent thermal management systems and multifunctional thermal systems. This project addresses the evaluation of the mechanical and thermal properties of metallic cellular solid (MCS) materials; those that are lightweight; high strength, tunable, multifunctional and affordable. A portion of the work includes understanding the mechanical properties of honeycomb structured cellular solids upon impact testing under ambient, water-immersed, liquid nitrogen-cooled, and liquid nitrogen-immersed conditions. Additionally, this study will address characterization techniques of the aluminum honeycomb's ability to resist multiple high-rate loadings or impacts in varying environmental conditions, using various techniques for the quantitative and qualitative determination for commercial applicability.

  19. The impact of twenty years of noise research on nuclear power plant design, instrumentation and control

    International Nuclear Information System (INIS)

    Kemeny, L.G.

    1975-01-01

    Early investigations demonstrated that time constants and the dynamic characteristics of low energy nuclear systems could be elegantly determined by correlation of spectral analysis of fluctuating signals from ion chambers and proportional counters. Analyses of the time series information and the multi-filtering operations in the frequency domain were time consuming and tedious projects due to the lack of suitable data processing equipment. During the last decade, the significant advances were the recognition of the advantages of the two-channel cross-correlation technique and the realisation that the dynamic behaviour of nuclear power plant at power could be monitored and studied in depth by the cross-correlation of mechanical, thermal and hydrodynamic signals with neutronic information. The former concept led to the development of theoretical models for spatial and energy-dependent noise fields within a nuclear system. The latter opened a floodgate of potential advances in nuclear power plant design optimization, control and safety instrumentation, and control and safety diagnostic systems. (U.K.)

  20. Advances in Field Deployable Instrumented Particles for the Study of Alluvial Transport Mechanisms

    Science.gov (United States)

    Dillon, B.; Strom, K.

    2017-12-01

    Advances in microelectromechanical systems (MEMs) in the past decade have lead to the development of various instrumented or "smart" particles for use in the study of alluvial transport. The goal of many of these devices is to collect data on the interaction between hydrodynamic turbulence and individual sediment particles. Studying this interaction provides a basis to better understand entrainment and deposition processes which leads to better predictive morphologic and transport models. In collecting data on these processes, researchers seek to capture the time history of the forces incident on the particle and the particle's reaction. Many methods have been employed to capture this data - miniaturized pressure traps, accelerometers, gyroscopes, MEMs pressure transducers, and cantilevered load cells. However no system to date has been able to capture the pressure forces incident on the particle and its reaction while remaining mobile and of a size and density comparable to most gravels. Advances in the development, deployment, and use of waterproofed laboratory instrumentation have led our research group to develop such a particle. This particle has been used in both laboratory settings and large-scale fluvial environments (coupled with a field-deployable PIV system) to capture data on turbulent erosion processes. This system advances the practice in several ways: 1) It is, at present, the smallest (⌀ 19mm) instrumented erodible particle reported in the literature. 2) It contains novel developments in pressure sensing technology which allow the inclusion of six pressure ports, a 3-axis accelerometer, and a 1-axis gyroscope - all of which can be recorded simultaneously. 3) It expands the researcher's abilities to gather data on phenomena that, previously, have mandated the use of a laboratory scale model. The use of this system has generated observations of the so-called very large scale motions (VLSMs) in a reach of the Virginia section of the New River. Their

  1. Evaluation of mechanical properties and low velocity impact characteristics of balsa wood and urethane foam applied to impact limiter of nuclear spent fuel shipping cask

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Junsung; Shin, Kwangbok [Hanbat Nat' l Univ., Daejeon (Korea, Republic of); Choi, Woosuk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-11-15

    The paper aims to evaluate the low velocity impact responses and mechanical properties of balsa wood and urethane foam core materials and their sandwich panels, which are applied as the impact limiter of a nuclear spent fuel shipping cask. For the urethane foam core, which is isotropic, tensile, compressive, and shear mechanical tests were conducted. For the balsa wood core, which is orthotropic and shows different material properties in different orthogonal directions, nine mechanical properties were determined. The impact test specimens for the core material and their sandwich panel were subjected to low velocity impact loads using an instrumented testing machine at impact energy levels of 1, 3, and 5J. The experimental results showed that both the urethane foam and the balsa wood core except in the growth direction (z-direction) had a similar impact response for the energy absorbing capacity, contact force, and indentation. Furthermore, it was found that the urethane foam core was suitable as an impact limiter material owing to its resistance to fire and low cost, and the balsa wood core could also be strongly considered as an impact limiter material for a lightweight nuclear spent fuel shipping cask.

  2. Fluid Mechanics Experiments as a Unifying Theme in the Physics Instrumentation Laboratory Course

    Science.gov (United States)

    Borrero-Echeverry, Daniel

    2017-11-01

    We discuss the transformation of a junior-level instrumentation laboratory course from a sequence of cookbook lab exercises to a semester-long, project-based course. In the original course, students conducted a series of activities covering the usual electronics topics (amplifiers, filters, oscillators, logic gates, etc.) and learned basic LabVIEW programming for data acquisition and analysis. Students complained that these topics seemed disconnected and not immediately applicable to ``real'' laboratory work. To provide a unifying theme, we restructured the course around the design, construction, instrumentation of a low-cost Taylor-Couette cell where fluid is sheared between rotating coaxial cylinders. The electronics labs were reworked to guide students from fundamental electronics through the design and construction of a stepper motor driver, which was used to actuate the cylinders. Some of the legacy labs were replaced with a module on computer-aided design (CAD) in which students designed parts for the apparatus, which they then built in the departmental machine shop. Signal processing topics like spectral analysis were introduced in the context of time-series analysis of video data acquired from flow visualization. The course culminated with a capstone project in which students conducted experiments of their own design on a variety of topics in rheology and nonlinear dynamics.

  3. Rubbish tips rehabilitation. Degradation mechanisms and impacts; Rehabilitation des decharges. Mecanismes de degradation et impacts

    Energy Technology Data Exchange (ETDEWEB)

    Chassagnac, Th. [CSZ AZUR, 69 - Lyon (France)

    2005-06-01

    Waste storage activity really started in the beginning of the industrial era when the consumption of goods has led to a production of wastes higher than the environment assimilation capacity. The waste storage and disposal activity has led to environmental impacts and risks which need to be evaluated and, if needed, processed. Waste storage remains the most common way of wastes elimination because of its simpleness and low cost. However, the closing down of sites is today strictly controlled by the law and the rehabilitation problems concerns mainly the ancient sites. The waste storage domain is at the crossroads of multiple scientific domains like: hydrogeology, rudology, biology, hydraulics and hydrology, water and gases processing, ecology, health sciences and risk assessments, and thus requires a multi-disciplinary approach. This article deals with the rehabilitation of rubbish tips and presents: 1 - the typology and regulatory evolution of waste storage centers; 2 - the main pollutants, their mechanisms and way of impact on the environment: typology of pollutants (origin and nature; mobility influencing factors; risk, hazard, exposure and impact notions); impacts on air (origin and mechanism of biogas generation, biogas composition, mass status of biogas production, risks linked with biogas); impact on waters (leachates; hydric status; impact on groundwaters; impact on surface waters; impact on soils and natural ecosystems; other harmful effects: aesthetics, noise, vermin; stability). (J.S.)

  4. Characteristic and Competency Measurement Instrument Development for Maintenance Staff of Mechanical Expertise with SECI Method: A Case of Manufacturing Company

    Science.gov (United States)

    Mahatmavidya, P. A.; Soesanto, R. P.; Kurniawati, A.; Andrawina, L.

    2018-03-01

    Human resource is an important factor for a company to gain competitiveness, therefore competencies of each individual in a company is a basic characteristic that is taken into account. The increasing employee’s competency will affect directly to the company's performance. The purpose of this research is to improve the quality of human resources of maintenance staff in manufacturing company by designing competency measurement instrument that aims to assess the competency of employees. The focus of this research is the mechanical expertise of maintenance staff. SECI method is used in this research for managing knowledge that is held by senior employees regarding employee competence of mechanical expertise. The SECI method converts the knowledge of a person's tacit knowledge into an explicit knowledge so that the knowledge can be used by others. The knowledge that is gathered from SECI method is converted into a list of competence and break down into the detailed competency. Based on the results of this research, it is known that 11 general competencies, 17 distinctive competencies, 20 indicators, and 20 item list for assessing the competencies are developed. From the result of competency breakdown, the five-level instrument of measurement is designed which can assist in assessing employee’s competency for mechanical expertise.

  5. CARMENES-NIR channel spectrograph cooling system AIV: thermo-mechanical performance of the instrument

    Science.gov (United States)

    Becerril, S.; Mirabet, E.; Lizon, J. L.; Abril, M.; Cárdenas, C.; Ferro, I.; Morales, R.; Pérez, D.; Ramón, A.; Sánchez-Carrasco, M. A.; Quirrenbach, A.; Amado, P.; Ribas, I.; Reiners, A.; Caballero, J. A.; Seifert, W.; Herranz, J.

    2016-07-01

    CARMENES is the new high-resolution high-stability spectrograph built for the 3.5m telescope at the Calar Alto Observatory (CAHA, Almería, Spain) by a consortium formed by German and Spanish institutions. This instrument is composed by two separated spectrographs: VIS channel (550-1050 nm) and NIR channel (950- 1700 nm). The NIR-channel spectrograph's responsible is the Instituto de Astrofísica de Andalucía (IAACSIC). It has been manufactured, assembled, integrated and verified in the last two years, delivered in fall 2015 and commissioned in December 2015. One of the most challenging systems in this cryogenic channel involves the Cooling System. Due to the highly demanding requirements applicable in terms of stability, this system arises as one of the core systems to provide outstanding stability to the channel. Really at the edge of the state-of-the-art, the Cooling System is able to provide to the cold mass ( 1 Ton) better thermal stability than few hundredths of degree within 24 hours (goal: 0.01K/day). The present paper describes the Assembly, Integration and Verification phase (AIV) of the CARMENES-NIR channel Cooling System implemented at IAA-CSIC and later installation at CAHA 3.5m Telescope, thus the most relevant highlights being shown in terms of thermal performance. The CARMENES NIR-channel Cooling System has been implemented by the IAA-CSIC through very fruitful collaboration and involvement of the ESO (European Southern Observatory) cryo-vacuum department with Jean-Louis Lizon as its head and main collaborator. The present work sets an important trend in terms of cryogenic systems for future E-ELT (European Extremely Large Telescope) large-dimensioned instrumentation in astrophysics.

  6. Variation in posture quality across musical instruments and its impact during performances.

    Science.gov (United States)

    Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez Vidal, Aurora

    2018-06-01

    Bad posture increases the risk that a musician may suffer from musculoskeletal disorders. This study compared posture quality required by different instruments or families of instruments. Using an ad-hoc postural observation instrument embracing 11 postural variables, four experts evaluated the postures of 100 students attending a Spanish higher conservatory of music. The agreement of the experts' evaluations was statistically confirmed by a Cohen's κ value between 0.855 and 1.000 and a Kendall value between 0.709 and 1.000 (p instrument families and seated posture with respect to pelvic attitude, dorsal curvature and head alignment in both sagittal and frontal planes. This analysis also showed an association between instrument families and standing posture with respect to the frontal plane of the axis of gravity, pelvic attitude, head alignment in the frontal plane, the sagittal plane of the shoulders and overall posture. While certain postural defects appear to be common to all families of instruments, others are more characteristic of some families than others. The instrument associated with the best posture quality was the bagpipe, followed by percussion and strings.

  7. Labour Standards and Trade: In Search of Impact and Alternative Instruments

    Directory of Open Access Journals (Sweden)

    Jan Orbie

    2017-12-01

    Full Text Available Labour standards have become an almost routine feature of trade agreements. However, we have little knowledge about whether this linkage is effective; both in absolute terms but also in comparison to other instruments that promote labour standards on a global level. Such alternative instruments include public-private agreements, value chain management and procurement policies. The articles in this thematic issue will provide insights that further the debate on the effectiveness of the connection between labour rights and international trade, looking at both ‘traditional’ trade agreements and ‘alternative’ instruments.

  8. A variable stiffness mechanism for steerable percutaneous instruments: integration in a needle.

    Science.gov (United States)

    De Falco, Iris; Culmone, Costanza; Menciassi, Arianna; Dankelman, Jenny; van den Dobbelsteen, John J

    2018-06-04

    Needles are advanced tools commonly used in minimally invasive medical procedures. The accurate manoeuvrability of flexible needles through soft tissues is strongly determined by variations in tissue stiffness, which affects the needle-tissue interaction and thus causes needle deflection. This work presents a variable stiffness mechanism for percutaneous needles capable of compensating for variations in tissue stiffness and undesirable trajectory changes. It is composed of compliant segments and rigid plates alternately connected in series and longitudinally crossed by four cables. The tensioning of the cables allows the omnidirectional steering of the tip and the stiffness tuning of the needle. The mechanism was tested separately under different working conditions, demonstrating a capability to exert up to 3.6 N. Afterwards, the mechanism was integrated into a needle, and the overall device was tested in gelatine phantoms simulating the stiffness of biological tissues. The needle demonstrated the capability to vary deflection (from 11.6 to 4.4 mm) and adapt to the inhomogeneity of the phantoms (from 21 to 80 kPa) depending on the activation of the variable stiffness mechanism. Graphical abstract ᅟ.

  9. The dynamics of technology diffusion and the impacts of climate policy instruments in the decarbonisation of the global electricity sector

    International Nuclear Information System (INIS)

    Mercure, J.-F.; Pollitt, H.; Chewpreecha, U.; Salas, P.; Foley, A.M.; Holden, P.B.; Edwards, N.R.

    2014-01-01

    This paper presents an analysis of climate policy instruments for the decarbonisation of the global electricity sector in a non-equilibrium economic and technology diffusion perspective. Energy markets are driven by innovation, path-dependent technology choices and diffusion. However, conventional optimisation models lack detail on these aspects and have limited ability to address the effectiveness of policy interventions because they do not represent decision-making. As a result, known effects of technology lock-ins are liable to be underestimated. In contrast, our approach places investor decision-making at the core of the analysis and investigates how it drives the diffusion of low-carbon technology in a highly disaggregated, hybrid, global macroeconometric model, FTT:Power-E3MG. Ten scenarios to 2050 of the electricity sector in 21 regions exploring combinations of electricity policy instruments are analysed, including their climate impacts. We show that in a diffusion and path-dependent perspective, the impact of combinations of policies does not correspond to the sum of impacts of individual instruments: synergies exist between policy tools. We argue that the carbon price required to break the current fossil technology lock-in can be much lower when combined with other policies, and that a 90% decarbonisation of the electricity sector by 2050 is affordable without early scrapping. - Highlights: • Policy scenarios for decarbonising of the global electricity sector by 90%. • Strong synergies exist between different energy policy instruments. • Carbon pricing not a sufficient policy instrument for large emissions reductions. • Improved agent behaviour assumptions for energy modelling beyond cost-optimisation

  10. The Impact of Technology on Hawaii's Automotive Mechanics: An Analysis with Recommendations. Technological Impact Study Series.

    Science.gov (United States)

    Allen, Robert

    Because of the increasing use of microelectronic componentry in automobiles, vocational educators must reexamine existing automotive mechanics curricula to ensure that they can continue to provide relevant job training. After examining recent trends in the impact of computers and electronics on automotive design and engineering, existing auto…

  11. Long-Term Forecast 2012 - An impact analysis of existing policy instruments in energy- and climate area; Laangsiktsprognos 2012 - En konsekvensanalys av gaellande styrmedel inom energi- och klimatomraadet

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-01

    The Energy Agency has a mandate that under 'Ordinance on climate reporting' (SFS 2005:626) out projections for the energy sector of the European Parliament and Council Decision No 280/2004/EC concerning a 'Mechanism for monitoring the emissions of the Community greenhouse gas'. This report contains a reference trajectory until 2030, and two sensitivity scenarios. The forecast is based on existing instruments, which means that results of the report should not be regarded as a proper projection of future energy, but as the impact of current policy instruments given different conditions such as economic growth and fuel prices. The Energy Authority's long-term forecasts are studied energy system's long-term development on the basis of policy instruments and several assumed conditions. The conditions for this long-term prognosis was established in January 2012 and has its basis in the policy instruments decided until the turn of 2011/2012. The work was partially done in conjunction with the Environmental Protection Agency assignments 'Assignment to provide input to a Swedish road map for Sweden without greenhouse gas emissions in 2050' as reported in December 2012. For a short-term development of the energy system the reader is referred to the Energy Authority's short-term forecasts that extend two to three years into the future and that are produced twice a year. Energy Agency's long-term projections are impact assessments with time horizon of 10-20 years which aims to describe the energy system's future development, provided a range of assumed conditions. If any of these conditions change it will also change forecast results. Economic development is an important assumption for the assessment of future energy.

  12. Incidence of microcracks in maxillary first premolars after instrumentation with three different mechanized file systems: a comparative ex vivo study.

    Science.gov (United States)

    Kfir, A; Elkes, D; Pawar, A; Weissman, A; Tsesis, I

    2017-01-01

    The objective of this study is to determine the potential for microcracks in the radicular dentin of first maxillary premolars using three different mechanized endodontic instrumentation systems. Eighty extracted maxillary first premolars with two root canals and no externally visible microcracks were selected. Root canal instrumentation was performed with either the ProTaper file system, the WaveOne primary file, or the self-adjusting file (SAF). Teeth with intact roots served as controls. The roots were cut into segments and examined with an intensive, small-diameter light source that was applied diagonally to the entire periphery of the root slice under ×20 magnification; the presence of microcracks and fractures was recorded. Pearson's chi-square method was used for statistical analysis, and significance was set at p systems, respectively, while no microcracks were present in the roots treated with the SAF (p = 0.008 and p = 0.035, respectively). Intact teeth presented with cracks in 5 % of the roots. The intensive, small-diameter light source revealed microcracks that could not be detected when using the microscope's light alone. Within the limitations of this study, it could be concluded that mechanized root canal instrumentation with the ProTaper and WaveOne systems in maxillary first premolars causes microcracks in the radicular dentin, while the use of the SAF file causes no such microcracks. Rotary and reciprocating files with large tapers may cause microcracks in the radicular dentin of maxillary first premolars. Less aggressive methods should be considered for these teeth.

  13. Curriculum Management Practices in Pedagogical Coordinations of Araucania Schools: Unveiling Technical/Instrumental Rationality, Control and Power Mechanisms Underlying

    Directory of Open Access Journals (Sweden)

    Juan Carlos Beltrán-Véliz

    2016-01-01

    Full Text Available This article consists of a case study regarding curriculum management practices of pedagogical coordinators in schools in Araucania area. The study aims to reveal technical/instrumental rationality, control and power mechanisms that underlie the curriculum management practices of such pedagogical coordinators of schools in Araucania region. A descriptive qualitative design based on the constructionist grounded theory and the constant comparative method is considered. Subjects studied included 12 technical leaders and 22 teachers from Araucania schools. Techniques for collecting information were semi-structured interview and texts for reading. Four categories rose from axial coding. Findings reveal that the teaching process is reduced to an instructional process. Furthermore, there is no uniformity of criteria regarding general functions that must be met. In the same extent, activity coordination is centered on bureaucratic administrative aspects, with main focus on task control. Regulations, programs and educational projects are used as control mechanisms. In addition, absence of spaces for professional discussion of pedagogical work and for constructive criticism is envisioned. This study concludes that pedagogical coordination practices are geared from an “instrumental rationality”, anchored in technical management set up in control and power.

  14. Mechanical and geometric features of endodontic instruments and its clinical effect

    OpenAIRE

    Hyeon-Cheol Kim

    2011-01-01

    Introduction The aim of this paper is to discuss the mechanical and geometric features of Nickel-titanium (NiTi) rotary files and its clinical effects. NiTi rotary files have been introduced to the markets with their own geometries and claims that they have better ability for the root canal shaping than their competitors. The contents of this paper include the (possible) interrelationship between the geometries of NiTi file (eg. tip, taper, helical angle, etc) and clinical performance ...

  15. Developing a new instrument to assess the impact of cancer in young adult survivors of childhood cancer.

    Science.gov (United States)

    Zebrack, Brad

    2009-09-01

    Thirty years of psychosocial oncology research have detailed issues having significant impact in both pediatric and adult populations; yet, few studies have captured the subtle and unique ways in which cancer impacts, disrupts and in some instances promotes the growth and development of adolescents and young adults with a cancer history. This paper reports the initiation of an effort to assess the impact of cancer in this young survivor population through the development of a new Impact of Cancer (IOC) instrument. 64 young adults aged 18-39 years and treated for a pediatric malignancy participated in face-to-face interviews and responded to questions prompting them to describe the impact of cancer on their physical, psychological, social and spiritual/existential well-being. Intent of analysis was to organize data into meaningful sub-categories from which to develop a set of candidate survey items that assess a range of problems, issues and changes that long-term survivors ascribe to their cancer experience. A total of 82 candidate survey items represented content across 11 topical domains including Body, Health and Body image, Treatment and Health Care, Having Children, Identity, Talking and Thinking About Cancer, Meaning of Cancer, Memory and Thinking, Finances, Family and Relationships, Socializing, and Life Goals. Assessing the instrument's psychometric properties in a large representative group of young cancer survivors is the next step for further development of such a measure. Once established, a valid and reliable Impact of Cancer instrument has the potential for identifying salient survivorship issues in a clinical setting.

  16. A method for three-dimensional analysis of the root canal system, before and after mechanical instrumentation, using X-ray Micro-computed tomography

    DEFF Research Database (Denmark)

    Markvart, Merete; Bjørndal, Lars; Larsen, Per

    . Extracted molar teeth were embedded in resin and kept moisturized. Each root canal was instrumented with NiTi instruments to #40. The teeth were scanned before and after instrumentation, using a microCT40 micro-tomography (SCANCO Medical AG, Bassersdorf, Switzerland). The reconstructed slices were imported......Clinical studies have shown a connection between the reduction of micro-organisms in the root canal and the degree of apical enlargement. The aim of this study was to create a non-invasive 3D model for monitoring the apical enlargement in molar teeth before and after mechanical instrumentation...

  17. Physical and mechanical properties of a thermomechanically treated NiTi wire used in the manufacture of rotary endodontic instruments.

    Science.gov (United States)

    Pereira, E S J; Peixoto, I F C; Viana, A C D; Oliveira, I I; Gonzalez, B M; Buono, V T L; Bahia, M G A

    2012-05-01

    To compare physical and mechanical properties of one conventional and one thermomechanically treated nickel-titanium (NiTi) wire used to manufacture rotary endodontic instruments. Two NiTi wires 1.0 mm in diameter were characterized; one of them, C-wire (CW), was processed in the conventional manner, and the other, termed M-Wire (MW), received an additional heat treatment according to the manufacturer. Chemical composition was determined by energy-dispersive X-ray spectroscopy, phase constitution by XRD and the transformation temperatures by DSC. Tensile loading/unloading tests and Vickers microhardness measurements were performed to assess the mechanical behaviour. Data were analysed using analysis of variance (α = 0.05). The two wires showed approximately the same chemical composition, close to the 1 : 1 atomic ratio, and the β-phase was the predominant phase present. B19' martensite and the R-phase were found in MW, in agreement with the higher transformation temperatures found in this wire compared with CW, whose transformation temperatures were below room temperature. Average Vickers microhardness values were similar for MW and CW (P = 0.91). The stress at the transformation plateau in the tensile load-unload curves was lower and more uniform in the M-Wire, which also showed the smallest stress hysteresis and apparent elastic modulus. The M-Wire had physical and mechanical properties that can render endodontic instruments more flexible and fatigue resistant than those made with conventionally processed NiTi wires. © 2011 International Endodontic Journal.

  18. Analysis of mechanical preparations in extracted teeth using ProTaper rotary instruments: value of the safety quotient.

    Science.gov (United States)

    Blum, J Y; Machtou, P; Ruddle, C; Micallef, J P

    2003-09-01

    The purpose of this study was to apply the Endographe to analyze the vertical forces and torque developed during mechanical preparations in extracted teeth. The data collected in this study may be used to calculate the safety quotient (SQ) as proposed by J.T. McSpadden. The SQ formula is defined as the torque required to break a file at D3 divided by the mean working torque required to cut dentin. The Endographe is a unique force-analyzer device equipped to measure, record, and generate graphs of the vertical forces and torque exerted during root canal preparation. All preparations were performed by endodontists in roots with narrow, more restrictive canals, larger, more open canals, or in roots sectioned in two halves. All canals, including the sectioned canals, were prepared with ProTaper files in accordance with the manufacturer's guidelines for use. For narrow canals, the mean values of the generated vertical forces (g) and torque (g.cm) varied from 80 (+/- 20) g (SX) to 232 (+/- 60) g (F2) and from 80 (+/- 24) g x cm (F1) to 150 (+/- 45) g x cm (S2), respectively. For large canals, the mean values of the generated vertical forces (g) and torque (g x cm) varied from 80 (+/- 20) g (SX) to 340 (+/- 20) g (F1) and from 31 (+/- 9) g x cm (S2) to 96 (+/- 35) g x cm (SX), respectively. The SQ varied from 0.93 to 7.95 for narrow canals and from 1.58 to 14.50 for large canals. The SQ is intended to provide values that can be analyzed to predict whether a rotary file will have a tendency to break or will work safely during clinical use. However, if the formula is going to provide useful information, it must index the "rotation to failure torque" with the "mean working torque" at a specific location along the cutting blades of a file. Additionally, this mathematical formula does not account for factors such as the concentration of forces, the way the instruments are used, or the wear of the instruments. A precise protocol for canal preparation should emphasize using

  19. Structural Composite Supercapacitors: Electrical and Mechanical Impact of Separators and Processing Conditions

    Science.gov (United States)

    2013-09-01

    Structural Composite Supercapacitors : Electrical and Mechanical Impact of Separators and Processing Conditions by Edwin B. Gienger, James F...Proving Ground, MD 21005-5066 ARL-TR-6624 September 2013 Structural Composite Supercapacitors : Electrical and Mechanical Impact of...2012 4. TITLE AND SUBTITLE Structural Composite Supercapacitors : Electrical and Mechanical Impact of Separators and Processing Conditions 5a

  20. Instrumented impact testing as a way to obtain further information on the behaviour of steel in welded constructions

    International Nuclear Information System (INIS)

    Nielsen, A.

    1976-05-01

    Based on experience gained from instrumented impact testing of ten different mild steels using test pieces of different geometrical shape (Charpy V-notch, Charpy knife-notch, DVM, Schnadt K 0 , Ksub(0.5), K 1 and K 2 ), some general features of the fracture process during impact testing are discussed. Steels can be divided into two main groups that are significantly different with respect to the behaviour during Charpy V-notch testing. The difference vanishes when a crack-like notch is used, and other properties of steel are revealed. It is evident that, even when modified impact testing bears little resemblance to what is happening in an actual steel construction. For the purpose of investigating the fracture conditions in welds, it seems more significant to relate the dynamic aspects to the speed of propagation of the crack when it starts to penetrate the volume considered at a certain stress level. (author)

  1. How the RRR neutronic characteristics impact on the mechanical design

    International Nuclear Information System (INIS)

    Villarino, E.; Coquibus, K.

    2005-01-01

    This paper describes how the neutronic characteristics of a very demanding research reactor facility impact on the mechanical design of the reactor core. The Replacement Research Reactor (RRR) for the Australian Nuclear Science and Technology Organization is described making emphasis in the mechanical solutions to improve the core performance. The compact core is located inside a chimney, surrounded by heavy water contained in the Reflector Vessel. The whole assembly is at the bottom of the Reactor Pool, which is full of de-mineralized light water acting as coolant and moderator and biological shielding. The core is an array of sixteen plate-type Fuel Assemblies (FAs) and five absorber plates, which are called Control Plates (CP). The coolant is light water, which flows upwards. The final design of the core layout and control guide boxes was adopted to minimize the flux and PPF perturbation during the normal operation. The four lateral control plates are used mainly to shutdown the reactor and to compensate large reactivity transients. The central and cruciform regulating plate is used to compensate the reactivity change during the cycle operation. The regulating plate does minimize perturbation on PPF and irradiation fluxes. The design of the reflector tank fulfills all the flux requirements for the irradiation facilities and also the flux perturbation between irradiation facilities. (authors)

  2. The impact of instrument-specific musical training on rhythm perception and production

    Directory of Open Access Journals (Sweden)

    Tomas Edward Matthews

    2016-02-01

    Full Text Available Various studies have shown that musical training can improve rhythmic perception and production. These findings tell us that music training can result in rhythm processing advantages but they do not tell us whether practicing a particular instrument could lead to specific effects on rhythm perception or production. The current study used a battery of four rhythm perception and production tasks that were designed to test both higher- and lower-level aspects of rhythm processing. Four groups of musicians (drummers, singers, pianists, string players and a control group of non-musicians were tested. Within-task differences in performance showed that factors such as meter, metrical complexity, tempo and beat phase significantly affected the ability to perceive and synchronize taps to a rhythm or beat. Musicians showed better performance on all rhythm tasks compared to non-musicians. Interestingly, our results revealed no significant differences between musician groups for the vast majority of task measures. This is despite the fact that all musicians were selected to have the majority of their training on the target instrument, had on average more than ten years of experience on their instrument, and were currently practicing. These results suggest that general musical experience is more important than specialized musical experience with regards to perception and production of rhythms.

  3. The Impact of Instrument-Specific Musical Training on Rhythm Perception and Production.

    Science.gov (United States)

    Matthews, Tomas E; Thibodeau, Joseph N L; Gunther, Brian P; Penhune, Virginia B

    2016-01-01

    Studies comparing musicians and non-musicians have shown that musical training can improve rhythmic perception and production. These findings tell us that training can result in rhythm processing advantages, but they do not tell us whether practicing a particular instrument could lead to specific effects on rhythm perception or production. The current study used a battery of four rhythm perception and production tasks that were designed to test both higher- and lower-level aspects of rhythm processing. Four groups of musicians (drummers, singers, pianists, string players) and a control group of non-musicians were tested. Within-task differences in performance showed that factors such as meter, metrical complexity, tempo, and beat phase significantly affected the ability to perceive and synchronize taps to a rhythm or beat. Musicians showed better performance on all rhythm tasks compared to non-musicians. Interestingly, our results revealed no significant differences between musician groups for the vast majority of task measures. This was despite the fact that all musicians were selected to have the majority of their training on the target instrument, had on average more than 10 years of experience on their instrument, and were currently practicing. These results suggest that general musical experience is more important than specialized musical experience with regards to perception and production of rhythms.

  4. Impact of instrumental response on observed ozonesonde profiles: First-order estimates and implications for measures of variability

    Science.gov (United States)

    Clifton, G. T.; Merrill, J. T.; Johnson, B. J.; Oltmans, S. J.

    2009-12-01

    Ozonesondes provide information on the ozone distribution up to the middle stratosphere. Ozone profiles often feature layers, with vertically discrete maxima and minima in the mixing ratio. Layers are especially common in the UT/LS regions and originate from wave breaking, shearing and other transport processes. ECC sondes, however, have a moderate response time to significant changes in ozone. A sonde can ascend over 350 meters before it responds fully to a step change in ozone. This results in an overestimate of the altitude assigned to layers and an underestimate of the underlying variability in the amount of ozone. An estimate of the response time is made for each instrument during the preparation for flight, but the profile data are typically not processed to account for the response. Here we present a method of categorizing the response time of ECC instruments and an analysis of a low-pass filter approximation to the effects on profile data. Exponential functions were fit to the step-up and step-down responses using laboratory data. The resulting response time estimates were consistent with results from standard procedures, with the up-step response time exceeding the down-step value somewhat. A single-pole Butterworth filter that approximates the instrumental effect was used with synthetic layered profiles to make first-order estimates of the impact of the finite response time. Using a layer analysis program previously applied to observed profiles we find that instrumental effects can attenuate ozone variability by 20-45% in individual layers, but that the vertical offset in layer altitudes is moderate, up to about 150 meters. We will present results obtained using this approach, coupled with data on the distribution of layer characteristics found using the layer analysis procedure on profiles from Narragansett, Rhode Island and other US sites to quantify the impact on overall variability estimates given ambient distributions of layer occurrence, thickness

  5. Instrumented Taylor anvil-on-rod impact tests for validating applicability of standard strength models to transient deformation states

    Science.gov (United States)

    Eakins, D. E.; Thadhani, N. N.

    2006-10-01

    Instrumented Taylor anvil-on-rod impact tests have been conducted on oxygen-free electronic copper to validate the accuracy of current strength models for predicting transient states during dynamic deformation events. The experiments coupled the use of high-speed digital photography to record the transient deformation states and laser interferometry to monitor the sample back (free surface) velocity as a measure of the elastic/plastic wave propagation through the sample length. Numerical continuum dynamics simulations of the impact and plastic wave propagation employing the Johnson-Cook [Proceedings of the Seventh International Symposium on Ballistics, 1983, The Netherlands (Am. Def. Prep. Assoc. (ADPA)), pp. 541-547], Zerilli-Armstrong [J. Appl. Phys. C1, 1816 (1987)], and Steinberg-Guinan [J. Appl. Phys. 51, 1498 (1980)] constitutive equations were used to generate transient deformation profiles and the free surface velocity traces. While these simulations showed good correlation with the measured free surface velocity traces and the final deformed sample shape, varying degrees of deviations were observed between the photographed and calculated specimen profiles at intermediate deformation states. The results illustrate the usefulness of the instrumented Taylor anvil-on-rod impact technique for validating constitutive equations that can describe the path-dependent deformation response and can therefore predict the transient and final deformation states.

  6. Instrumented anvil-on-rod impact experiments for validating constitutive strength model for simulating transient dynamic deformation response of metals

    International Nuclear Information System (INIS)

    Martin, M.; Shen, T.; Thadhani, N.N.

    2008-01-01

    Instrumented anvil-on-rod impact experiments were performed to access the applicability of this approach for validating a constitutive strength model for dynamic, transient-state deformation and elastic-plastic wave interactions in vanadium, 21-6-9 stainless steel, titanium, and Ti-6Al-4V. In addition to soft-catching the impacted rod-shaped samples, their transient deformation states were captured by high-speed imaging, and velocity interferometry was used to record the sample back (free) surface velocity and monitor elastic-plastic wave interactions. Simulations utilizing AUTODYN-2D hydrocode with Steinberg-Guinan constitutive equation were used to generate simulated free surface velocity traces and final/transient deformation profiles for comparisons with experiments. The simulations were observed to under-predict the radial strain for bcc vanadium and fcc steel, but over-predict the radial strain for hcp titanium and Ti-6Al-4V. The correlations illustrate the applicability of the instrumented anvil-on-rod impact test as a method for providing robust model validation based on the entire deformation event, and not just the final deformed state

  7. Mechanical behavior of M-Wire and conventional NiTi wire used to manufacture rotary endodontic instruments.

    Science.gov (United States)

    Pereira, Erika S J; Gomes, Renata O; Leroy, Agnès M F; Singh, Rupinderpal; Peters, Ove A; Bahia, Maria G A; Buono, Vicente T L

    2013-12-01

    Comparison of physical and mechanical properties of one conventional and a new NiTi wire, which had received an additional thermomechanical treatment. Specimens of both conventional (NiTi) and the new type of wire, called M-Wire (MW), were subjected to tensile and three-point bending tests, Vickers microhardness measurements, and to rotating-bending fatigue tests at a strain-controlled level of 6%. Fracture surfaces were observed by scanning electron microscopy and the non-deformed microstructures by transmission electron microscopy. The thermomechanical treatment applied to produce the M-Wire apparently increased the tensile strength and Vickers microhardness of the material, but its apparent Young modulus was smaller than that of conventionally treated NiTi. The three-point bending tests showed a higher flexibility for MW which also exhibited a significantly higher number of cycles to failure. M-Wire presented mechanical properties that can render endodontic instruments more flexible and fatigue resistant than those made with conventionally processed NiTi wires. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  8. The Impact of Scholastic Instrumental Music and Scholastic Chess Study on the Standardized Test Scores of Students in Grades Three, Four, and Five

    Science.gov (United States)

    Martinez, Edwin E.

    2012-01-01

    This study examines the impact of instrumental music study and group chess lessons on the standardized test scores of suburban elementary public school students (grades three through five) in Levittown, New York. The study divides the students into the following groups and compares the standardized test scores of each: a) instrumental music…

  9. Prediction of wood mechanical and chemical properties in the presence and absence of blue stain using two near infrared instruments

    Science.gov (United States)

    Brian K. Via; Chi-Leung So; Todd F. Shupe; Lori G. Eckhardt; Michael Stine; Leslie H. Groom

    2005-01-01

    The objective of this research was to (a) determine if blue stain in solid wood influenced calibration equations developed from a nonstained wood population, (b) assess the bias introduced when scanning was performed by the slave instrument without calibration transfer from the master instrument and (c) partition absorbance-based variation by instrument, stain and...

  10. In Their Voice: Lower Secondary School Students' Beliefs about Playing Musical Instruments, and the Impact of the Instrument Lesson upon Those Beliefs

    Science.gov (United States)

    Lowe, Geoffrey

    2010-01-01

    Many young West Australians learn musical instruments through school based elective programs. However, many students drop out from these programs, particularly in lower secondary school. This paper reports on a study I conducted into the motives of 48 lower secondary school students for playing a musical instrument, and the role of the instrument…

  11. Environmental impacts assessment: Instruments for environmental policy making and resource management

    International Nuclear Information System (INIS)

    Cavelli, C.M.; Sartori, S.

    1993-06-01

    This review of evaluation criteria for environmental impacts assessments in Italy covers the following aspects: the efficacy of current Italian normatives governing assessment methods, the current approach of regional public administrations, the necessity for the creation of a national regulating board, environmental impacts assessment for complex environmental systems, the application of impacts assessment recommendations to resource development modelling in the planning of integrated environmental-economic systems, the involvement of the general public in decision making, techniques to determine the monetary worth of environmental resources, the use of multi-criteria analysis techniques

  12. Impact of heat treatments on the fatigue resistance of different rotary nickel-titanium instruments.

    Science.gov (United States)

    Braga, Lígia Carolina Moreira; Faria Silva, Ana Cristina; Buono, Vicente Tadeu Lopes; de Azevedo Bahia, Maria Guiomar

    2014-09-01

    The aim of this study was to assess the influence of M-Wire (Dentsply Tulsa Dental Specialties, Tulsa, OK) and controlled memory technologies on the fatigue resistance of rotary nickel-titanium (NiTi) files by comparing files made using these 2 technologies with conventional NiTi files. Files with a similar cross-sectional design and diameter were chosen for the study: new 30/.06 files of the EndoWave (EW; J. Morita Corp, Osaka, Japan), HyFlex (HF; Coltene/Whaledent, Inc, Cuyahoga Falls, OH), ProFile Vortex (PV; Dentsply Tulsa Dental Specialties, Tulsa, OK), and Typhoon (TYP; Clinician's Choice Dental Products, New Milford, CT) systems together with ProTaper Universal F2 instruments (PTU F2; Dentsply Maillefer, Ballaigues, Switzerland). The compositions and transformation temperatures of the instruments were analyzed using x-ray energy-dispersive spectroscopy and differential scanning calorimetry, whereas the mean file diameter values at 3 mm from the tip (D3) were measured using image analysis software. The average number of cycles to failure was determined using a fatigue test device. X-ray energy-dispersive spectroscopy analysis showed that, on average, all the instruments exhibited the same chemical composition, namely, 51% Ni-49% Ti. The PV, TYP, and HF files exhibited increased transformation temperatures. The PTU F2, PV, and TYP files had similar D3 values, which were less than those of the EW and HF files. The average number of cycles to failure values were 150% higher for the TYP files compared with the PV files and 390% higher for the HF files compared with the EW files. M-Wire and controlled memory technologies increase the fatigue resistance of rotary NiTi files. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. Impact of sound production by wind instruments on the temporomandibular system of male instrumentalists.

    Science.gov (United States)

    Pampel, Michael; Jakstat, Holger A; Ahlers, Oliver M

    2014-01-01

    Playing a wind instrument can be either a reason for overuse or a protecting factor against certain diseases. Some individuals have many findings but low morbidity while others have few findings but high morbidity. This contradictory phenomenon should be researched. The temporomandibular system (TMS) is a functional unit which comprises the mandible, associated muscles and bilateral joints with the temporal bone. The TMS is responsible for the generation of sound when wind instruments are played. Over the long-term and with intensive usage, this causes changes in the musculature and in the temporomandibular joint (TMJ) of wind musicians, often resulting in temporomandibular disorders (TMD). The aim of this study is to examine evidence that TMD constitute an occupational disease in wind musicians. TMD patients and wind musicians were examined by dental clinical functional analysis. 102 male subjects were divided into three groups: "healthy" individuals, wind musicians, and patients with TMD. Dental Examination was carried out based on focused inclusion of the research diagnostic criteria - TMD [1,7]. Findings were evaluated for statistical significance by first transferring data into a digital database [2,15], then generating T-Test und Wilcoxon-Test when non-Gaussian distribution appears and applying the Mann-Whitney rank sum test using Sigmaplot Version 1.1 software (Systat Software Inc, Washington, USA). The evaluation revealed that wind instrument musicians show a high incidence of developing TMD as the researchers found almost 100% morbidity regarding parafunctional habits and preauricular muscle pain of each adult and highly active musician. The result is highly significant (pTMS.

  14. Impact of Passive Safety on FHR Instrumentation Systems Design and Classification

    International Nuclear Information System (INIS)

    Holcomb, David Eugene

    2015-01-01

    Fluoride salt-cooled high-temperature reactors (FHRs) will rely more extensively on passive safety than earlier reactor classes. 10CFR50 Appendix A, General Design Criteria for Nuclear Power Plants, establishes minimum design requirements to provide reasonable assurance of adequate safety. 10CFR50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Reactors, provides guidance on how the safety significance of systems, structures, and components (SSCs) should be reflected in their regulatory treatment. The Nuclear Energy Institute (NEI) has provided 10 CFR 50.69 SSC Categorization Guideline (NEI-00-04) that factors in probabilistic risk assessment (PRA) model insights, as well as deterministic insights, through an integrated decision-making panel. Employing the PRA to inform deterministic requirements enables an appropriately balanced, technically sound categorization to be established. No FHR currently has an adequate PRA or set of design basis accidents to enable establishing the safety classification of its SSCs. While all SSCs used to comply with the general design criteria (GDCs) will be safety related, the intent is to limit the instrumentation risk significance through effective design and reliance on inherent passive safety characteristics. For example, FHRs have no safety-significant temperature threshold phenomena, thus enabling the primary and reserve reactivity control systems required by GDC 26 to be passively, thermally triggered at temperatures well below those for which core or primary coolant boundary damage would occur. Moreover, the passive thermal triggering of the primary and reserve shutdown systems may relegate the control rod drive motors to the control system, substantially decreasing the amount of safety-significant wiring needed. Similarly, FHR decay heat removal systems are intended to be running continuously to minimize the amount of safety-significant instrumentation needed to initiate

  15. "Fibromyalgia and quality of life: mapping the revised fibromyalgia impact questionnaire to the preference-based instruments".

    Science.gov (United States)

    Collado-Mateo, Daniel; Chen, Gang; Garcia-Gordillo, Miguel A; Iezzi, Angelo; Adsuar, José C; Olivares, Pedro R; Gusi, Narcis

    2017-05-30

    The revised version of the Fibromyalgia Impact Questionnaire (FIQR) is one of the most widely used specific questionnaires in FM studies. However, this questionnaire does not allow calculation of QALYs as it is not a preference-based measure. The aim of this study was to develop mapping algorithm which enable FIQR scores to be transformed into utility scores that can be used in the cost utility analyses. A cross-sectional survey was conducted. One hundred and 92 Spanish women with Fibromyalgia were asked to complete four general quality of life questionnaires, i.e. EQ-5D-5 L, 15D, AQoL-8D and SF-12, and one specific disease instrument, the FIQR. A direct mapping approach was adopted to derive mapping algorithms between the FIQR and each of the four multi-attribute utility (MAU) instruments. Health state utility was treated as the dependent variable in the regression analysis, whilst the FIQR score and age were predictors. The mean utility scores ranged from 0.47 (AQoL-8D) to 0.69 (15D). All correlations between the FIQR total score and MAU instruments utility scores were highly significant (p fibromyalgia specific questionnaire.

  16. IMPACT OF POLICIES AND PUBLIC FINANCING INSTRUMENTS ON R&D INVESTMENTS

    Directory of Open Access Journals (Sweden)

    Steliana SANDU

    2007-06-01

    Full Text Available This paper is based on the Romania country review, produced as internal working papers for the research project “Monitoring and analysis of policies and public financing instruments conducive to higher levels of R&D investment”. The aim of the project is to serve as support for policy developments in Europe, notably in the framework of CREST activities. It is running by a consortium of 7 partners:· UNU-MERIT (The Netherlands, consortium leader·Technopolis (The Netherlands· PREST – University of Manchester (United Kingdom· ZEW (Germany· Joanneum Research (Austria· Wiseguys Ltd. (United Kingdom and INTRASOFT International (Luxembourg. Each country review provides expert’s view on the policy mix and its is to provide an exploratory analysis of the current policy mixes in place and detect the most important areas of interactions between instruments as well as new modes of policy governance that are particularly adapted (or detrimental for the building of policy mixes.

  17. Review: Wind impacts on plant growth, mechanics and damage.

    Science.gov (United States)

    Gardiner, Barry; Berry, Peter; Moulia, Bruno

    2016-04-01

    Land plants have adapted to survive under a range of wind climates and this involve changes in chemical composition, physical structure and morphology at all scales from the cell to the whole plant. Under strong winds plants can re-orientate themselves, reconfigure their canopies, or shed needles, leaves and branches in order to reduce the drag. If the wind is too strong the plants oscillate until the roots or stem fail. The mechanisms of root and stem failure are very similar in different plants although the exact details of the failure may be different. Cereals and other herbaceous crops can often recover after wind damage and even woody plants can partially recovery if there is sufficient access to water and nutrients. Wind damage can have major economic impacts on crops, forests and urban trees. This can be reduced by management that is sensitive to the local site and climatic conditions and accounts for the ability of plants to acclimate to their local wind climate. Wind is also a major disturbance in many plant ecosystems and can play a crucial role in plant regeneration and the change of successional stage. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Results and Insights on the Impact of Smoke on Digital Instrumentation and Control

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T. J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nowlen, S. P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2001-01-31

    Smoke can cause interruptions and upsets in active electronics. Because nuclear power plants are replacing analog with digital instrumentation and control systems, qualification guidelines for new systems are being reviewed for severe environments such as smoke and electromagnetic interference. Active digital systems, individual components, and active circuits have been exposed to smoke in a program sponsored by the U.S. Nuclear Regulatory Commission. The circuits and systems were all monitored during the smoke exposure, indicating any immediate effects of the smoke. The major effect of smoke has been to increase leakage currents (through circuit bridging across contacts and leads) and to cause momentary upsets and failures in digital systems. This report summarizes two previous reports and presents new results from conformal coating, memory chip, and hard drive tests. The report describes practices for mitigation of smoke damage through digital system design, fire barriers, ventilation, fire suppressants, and post fire procedures.

  19. The Sickness Impact Profile: Potential Use of a Health Status Instrument for Physician Training

    Science.gov (United States)

    Martin, Diane P.; And Others

    1976-01-01

    The Sickness Impact Profile (SIP) is designed to measure health status in terms of sickness-related changes in behavior. Its content incorporates the perspectives of clinicians, patients, and the apparently healthy, and consists of 235 items. Its reliability and validity were supported in a study with both experienced physicians and residents.…

  20. A visualization instrument to investigate the mechanical-electro properties of high temperature superconducting tapes under multi-fields

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wei; Zhang, Xingyi, E-mail: zhangxingyi@lzu.edu.cn; Liu, Cong; Zhang, Wentao; Zhou, Jun; Zhou, YouHe [Key Laboratory of Mechanics on Disaster and Environment in Western China Attached to the Ministry of Education of China, Lanzhou University, Lanzhou, Gansu 730000, People’s Republic of China and Department of Mechanics and Engineering Sciences, College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, Gansu 730000 (China)

    2016-07-15

    We construct a visible instrument to study the mechanical-electro behaviors of high temperature superconducting tape as a function of magnetic field, strain, and temperature. This apparatus is directly cooled by a commercial Gifford-McMahon cryocooler. The minimum temperature of sample can be 8.75 K. A proportion integration differentiation temperature control is used, which is capable of producing continuous variation of specimen temperature from 8.75 K to 300 K with an optional temperature sweep rate. We use an external loading device to stretch the superconducting tape quasi-statically with the maximum tension strain of 20%. A superconducting magnet manufactured by the NbTi strand is applied to provide magnetic field up to 5 T with a homogeneous range of 110 mm. The maximum fluctuation of the magnetic field is less than 1%. We design a kind of superconducting lead composed of YBa2Cu3O7-x coated conductor and beryllium copper alloy (BeCu) to transfer DC to the superconducting sample with the maximum value of 600 A. Most notably, this apparatus allows in situ observation of the electromagnetic property of superconducting tape using the classical magnetic-optical imaging.

  1. Binary logistic regression-Instrument for assessing museum indoor air impact on exhibits.

    Science.gov (United States)

    Bucur, Elena; Danet, Andrei Florin; Lehr, Carol Blaziu; Lehr, Elena; Nita-Lazar, Mihai

    2017-04-01

    This paper presents a new way to assess the environmental impact on historical artifacts using binary logistic regression. The prediction of the impact on the exhibits during certain pollution scenarios (environmental impact) was calculated by a mathematical model based on the binary logistic regression; it allows the identification of those environmental parameters from a multitude of possible parameters with a significant impact on exhibitions and ranks them according to their severity effect. Air quality (NO 2 , SO 2 , O 3 and PM 2.5 ) and microclimate parameters (temperature, humidity) monitoring data from a case study conducted within exhibition and storage spaces of the Romanian National Aviation Museum Bucharest have been used for developing and validating the binary logistic regression method and the mathematical model. The logistic regression analysis was used on 794 data combinations (715 to develop of the model and 79 to validate it) by a Statistical Package for Social Sciences (SPSS 20.0). The results from the binary logistic regression analysis demonstrated that from six parameters taken into consideration, four of them present a significant effect upon exhibits in the following order: O 3 >PM 2.5 >NO 2 >humidity followed at a significant distance by the effects of SO 2 and temperature. The mathematical model, developed in this study, correctly predicted 95.1 % of the cumulated effect of the environmental parameters upon the exhibits. Moreover, this model could also be used in the decisional process regarding the preventive preservation measures that should be implemented within the exhibition space. The paper presents a new way to assess the environmental impact on historical artifacts using binary logistic regression. The mathematical model developed on the environmental parameters analyzed by the binary logistic regression method could be useful in a decision-making process establishing the best measures for pollution reduction and preventive

  2. Mechanical reduction of the intracanal Enterococcus faecalis population by Hyflex CM, K3XF, ProTaper Next, and two manual instrument systems: an in vitro comparative study.

    Science.gov (United States)

    Tewari, Rajendra K; Ali, Sajid; Mishra, Surendra K; Kumar, Ashok; Andrabi, Syed Mukhtar-Un-Nisar; Zoya, Asma; Alam, Sharique

    2016-05-01

    In the present study, the effectiveness of three rotary and two manual nickel titanium instrument systems on mechanical reduction of the intracanal Enterococcus faecalis population was evaluated. Mandibular premolars with straight roots were selected. Teeth were decoronated and instrumented until 20 K file and irrigated with physiological saline. After sterilization by ethylene oxide gas, root canals were inoculated with Enterococcus faecalis. The specimens were randomly divided into five groups for canal instrumentation: Manual Nitiflex and Hero Shaper nickel titanium files, and rotary Hyflex CM, ProTaper Next, and K3XF nickel titanium files. Intracanal bacterial sampling was done before and after instrumentation. After serial dilution, samples were plated onto the Mitis Salivarius agar. The c.f.u. grown were counted, and log10 transformation was calculated. All instrumentation systems significantly reduced the intracanal bacterial population after root canal preparation. ProTaper Next was found to be significantly more effective than Hyflex CM and manual Nitiflex and Hero Shaper. However, ProTaper Next showed no significant difference with K3XF. Canal instrumentation by all the file systems significantly reduced the intracanal Enterococcus faecalis counts. ProTaper Next was found to be most effective in reducing the number of bacteria than other rotary or hand instruments. © 2014 Wiley Publishing Asia Pty Ltd.

  3. Impact of lysozyme on stability mechanism of nanozirconia aqueous suspension

    Energy Technology Data Exchange (ETDEWEB)

    Szewczuk-Karpisz, Katarzyna, E-mail: k.szewczuk-karpisz@wp.pl; Wiśniewska, Małgorzata

    2016-08-30

    Highlights: • Adsorption and stabilization-destabilization properties of lysozyme (LSZ) in the nanozirconia-biopolymer solution system were determined. • The stability measurements were performed using turbidimetric method. • Lysozyme macromolecules undergo adsorption on the ZrO{sub 2} surface under electrostatic adsorbent-adsorbate attraction, i.e. at pH 6 and 9. • The biopolymer adsorption impact on the zirconia stability varies at different pH values. - Abstract: The effect of lysozyme (LSZ) presence on the zirconium(IV) oxide (ZrO{sub 2}) aqueous suspension stability was examined. The applied zirconia contains mesopores (with a diameter about 30 nm) and its mean particle size is about 100 nm. To determine the stability mechanism of ZrO{sub 2} suspension in the biopolymer presence, the adsorption and electrokinetic (surface charge density and zeta potential) measurements were performed in the pH range 3–10. The lysozyme adsorption on the nanozirconia surface proceeds mainly through electrostatic forces. Under solid-polymer repulsion conditions, there is no adsorption of lysozyme (pH < 6, C{sub NaCl} 0.01 mol/dm{sup 3}). The increase of solution ionic strength to 0.2 mol/dm{sup 3} causes screening of unfavourable forces and biopolymer adsorption becomes possible. The LSZ addition to the ZrO{sub 2} suspension influences its stability. At pH 3, 4.6 and 7.6, slight improvement of the system stability was obtained. In turn, at pH 9 considerable destabilization of nanozirconia particles covered by polymeric layers occurs.

  4. Rotary science and its impact on instrument separation: A focused review

    Science.gov (United States)

    Khasnis, Sandhya Anand; Kar, Prem Prakash; Kamal, Apoorva; Patil, Jayaprakash D.

    2018-01-01

    Efficient endodontic treatment demands thorough debridement of the root canal system with minimal procedural errors. The inherent weakness of nickel–titanium alloys is their unexpected breakage. Modifications in the design, manufacturing, thermomechanical and surface treatment of alloys and advancements in movement kinetics have shown to improve the fatigue properties of the alloys, reducing the incidence of separation. This review enlightens the impact of these factors on fatigue properties of the alloy. PMID:29674810

  5. Impacts and environmental administration in development projects: instruments for the political fixation

    International Nuclear Information System (INIS)

    Angel Sanint, Enrique

    1999-01-01

    Inside the scheme of the necessary environmental administration to evaluate, to mitigate, to correct and to compensate the environmental impacts of a development project the acting diagram is presented, belonging to the multi-objective analysis, like an interesting tool that contributes to consider restrictions and to keep in mind the economic aspect inside the process of politics fixation for the interaction between the environmental authority and the developers of projects in the three basic instances contemplated by the legislation like interaction points

  6. Physicians' decision process for drug prescription and the impact of pharmaceutical marketing mix instruments.

    Science.gov (United States)

    Campo, Katia; De Staebel, Odette; Gijsbrechts, Els; van Waterschoot, Walter

    2005-01-01

    This paper provides an in-depth, qualitative analysis of the physicians' decision process for drug prescription. Drugs in the considered therapeutic classes are mainly prescribed by specialists, treating patients with obligatory medical insurance, for a prolonged period of time. The research approach is specifically designed to capture the full complexity and sensitive nature of the physician's choice behavior, which appears to be more hybrid and less rational in nature than is often assumed in quantitative, model-based analyses of prescription behavior. Several interesting findings emerge from the analysis: (i) non-compensatory decision rules seem to dominate the decision process, (ii) consideration sets are typically small and change-resistant, (iii) drug cost is not a major issue for most physicians, (iv) detailing remains one of the most powerful pharmaceutical marketing instruments and is highly appreciated as a valuable and quick source of information, and (v) certain types of non-medical marketing incentives (such as free conference participation) may in some situations also influence drug choices.

  7. Modeling the impact of scaffold architecture and mechanical loading on collagen turnover in engineered cardiovascular tissues

    NARCIS (Netherlands)

    Argento, G.; de Jonge, N.; Söntjens, S.H.M.; Oomens, C.W.J.; Bouten, C.V.C.; Baaijens, F.P.T.

    2015-01-01

    The anisotropic collagen architecture of an engineered cardiovascular tissue has a major impact on its in vivo mechanical performance. This evolving collagen architecture is determined by initial scaffold microstructure and mechanical loading. Here, we developed and validated a theoretical and

  8. Ex Vivo Evaluation of Cementless Acetabular Cup Stability Using Impact Analyses with a Hammer Instrumented with Strain Sensors.

    Science.gov (United States)

    Tijou, Antoine; Rosi, Giuseppe; Hernigou, Philippe; Flouzat-Lachaniette, Charles-Henri; Haïat, Guillaume

    2017-12-27

    The acetabular cup (AC) implant stability is determinant for the success of cementless hip arthroplasty. A method based on the analysis of the impact force applied during the press-fit insertion of the AC implant using a hammer instrumented with a force sensor was developed to assess the AC implant stability. The aim of the present study was to investigate the performance of a method using a hammer equipped with strain sensors to retrieve the AC implant stability. Different AC implants were inserted in five bovine samples with different stability conditions leading to 57 configurations. The AC implant was impacted 16 times by the two hammers consecutively. For each impact; an indicator I S (respectively I F ) determined by analyzing the time variation of the signal corresponding to the averaged strain (respectively force) obtained with the stress (respectively strain) hammer was calculated. The pull-out force F was measured for each configuration. F was significantly correlated with I S (R² = 0.79) and I F (R² = 0.80). The present method has the advantage of not modifying the shape of the hammer that can be sterilized easily. This study opens new paths towards the development of a decision support system to assess the AC implant stability.

  9. Impact of energy policy instruments on the estimated level of underlying energy efficiency in the EU residential sector

    International Nuclear Information System (INIS)

    Filippini, Massimo; Hunt, Lester C.; Zorić, Jelena

    2014-01-01

    The promotion of energy efficiency is seen as one of the top priorities of EU energy policy (EC, 2010). In order to design and implement effective energy policy instruments, it is necessary to have information on energy demand price and income elasticities in addition to sound indicators of energy efficiency. This research combines the approaches taken in energy demand modelling and frontier analysis in order to econometrically estimate the level of energy efficiency for the residential sector in the EU-27 member states for the period 1996 to 2009. The estimates for the energy efficiency confirm that the EU residential sector indeed holds a relatively high potential for energy savings from reduced inefficiency. Therefore, despite the common objective to decrease ‘wasteful’ energy consumption, considerable variation in energy efficiency between the EU member states is established. Furthermore, an attempt is made to evaluate the impact of energy-efficiency measures undertaken in the EU residential sector by introducing an additional set of variables into the model and the results suggest that financial incentives and energy performance standards play an important role in promoting energy efficiency improvements, whereas informative measures do not have a significant impact. - Highlights: • The level of energy efficiency of the EU residential sector is estimated. • Considerable potential for energy savings from reduced inefficiency is established. • The impact of introduced energy-efficiency policy measures is also evaluated. • Financial incentives are found to promote energy efficiency improvements. • Energy performance standards also play an important role

  10. The impact of instrumentation and control requirements on the design changes of the Westinghouse ''NSSS'' of Almaraz, Lemoniz and Asco

    International Nuclear Information System (INIS)

    Gerini, P.M.; Naredo, F.P.; Williams, D.W.

    1978-01-01

    For the nuclear power plants Almaraz, Lemoniz and Asco the NSSS set is supplied by Westinghouse. Purchasing contracts were signed in 1971 and projects design took into account the compliance with the regulatory requirements for licensing, issued and standing that time. Since 1971 licensing regulations have been subjected to a deep revision due to the issue of new standards and guides and revision of other affecting altogether the engineering design of nuclear power plants. This situation was reasonably reflected on several consecutive design revisions for the case of the Almaraz, Lemoniz and Asco Nuclear plants. This impact, from the viewpoint of the instrumentation and control context, and referred to the NSSS is analyzed in the report. In particular, attention is paid to the safeguards actuation logic, testing capability and physical separation criteria as contemplated into the regulatory requirements starting from 1971.(J.E.de C)

  11. The mechanics of large meteoroid impacts in the earth's oceans

    Science.gov (United States)

    Melosh, H. J.

    1982-01-01

    The sequence of events subsequent to the impact of a large meteoroid in an ocean differs in several respects from an impact on land. Even if the meteoroid is large enough to produce a crater on the sea floor (that is, larger than a few km in diameter), the presence of water affects the character of the early-time events. The principal difference between land and oceanic impacts is the expansion of shock-vaporized water following an oceanic impact. A steam explosion follows the meteoroid's deposition of energy in the target. Shocked water expands from an initial pressure of 3 to 6 Mbar for 20-30 km/second impacts, ejecting water vapor and dust from the vaporized meteoroid several hundred km into the atmosphere. The violent vapor plume thus formed may explain how dust with a dominantly meteoritic composition can be dispersed to form a world-wide dust layer, as required by the Alvarez hypothesis.

  12. Latest Observations of Interstellar Plasma Waves, Radio Emissions, and Dust Impacts from the Voyager 1 Plasma Wave Instrument

    Science.gov (United States)

    Gurnett, D. A.

    2017-12-01

    Voyager 1, which is now 140 AU (Astronomical Units) from the Sun, crossed the heliopause into interstellar space in 2012 at a heliospheric radial distance of 121 AU. Since crossing the heliopause the plasma wave instrument has on several occasions detected plasma oscillations and radio emissions at or near the electron plasma frequency. The most notable of these events occurred in Oct.-Nov. 2012, April-May 2013, Feb.-Nov. 2014, and Sept.-Nov. 2015. Most recently, a very weak emission has been observed at or near the electron plasma frequency through most of 2016. These emissions are all believed to be produced by shock waves propagating into the interstellar medium from energetic solar events. The oscillation frequency of the plasma indicates that the electron density in the interstellar plasma has gradually increased from about 0.06 cm-3 near the heliopause to about 0.12 cm-3 in the most recent data. The plasma wave instrument also continues to detect impacts of what are believed to be interstellar dust grains at an impact rate of a few per year. Comparisons with Ulysses observations of similar interstellar dust near 5 AU suggest that the dust grains have sizes in the range from about 0.1 to 1 micrometer. Although the statistics are poor due to the low count rate, the dust flux observed in the outer heliosphere appears to be as much as a factor of two greater than that observed in the interstellar medium. Since the dust particles are likely to be charged, this increase in the heliosphere suggests that there may be a significant electrodynamic interaction of the dust particles with the heliospheric magnetic field.

  13. Mechanisms controlling the impact of multi-year drought on mountain hydrology

    Science.gov (United States)

    Roger C. Bales; Michael L. Goulden; Carolyn T. Hunsaker; Martha H. Conklin; Peter C. Hartsough; Anthony T. O’Geen; Jan W. Hopmans; Mohammad Safeeq

    2018-01-01

    Mountain runoff ultimately reflects the difference between precipitation (P) and evapotranspiration (ET), as modulated by biogeophysical mechanisms that intensify or alleviate drought impacts. These modulating mechanisms are seldom measured and not fully understood. The impact of the warm 2012–15 California drought on the...

  14. A Novel Instrumented Human Head Surrogate for the Impact Evaluation of Helmets

    Directory of Open Access Journals (Sweden)

    Nicola Petrone

    2018-02-01

    Full Text Available A novel Human Head Surrogate was obtained from available MRI scans of a 50th percentile male human head. Addictive manufacturing was used to produce the skull, the brain and the skin. All original MRI geometries were partially smoothed and adjusted to provide the best biofidelity compatible with printing and molding technology. The skull was 3D-printed in ABS and ten pressure sensors were placed into it. The brain surrogate was cast from silicon rubber in the 3D-printed plastic molds. Nine tri-axial accelerometers (placed at the tops of the lobes, at the sides of the lobes, in the cerebellum and in the center of mass and a three-axis gyroscope (at the center of mass were inserted into the silicon brain during casting. The cranium, after assembly with brain, was filled with silicon oil mimicking the cerebral fluid. Silicon rubber was cast in additional 3D-printed molds to form the skin surrounding the cranium. The skull base was adapted to be compatible with the Hybrid-III neck and allow the exit of brain sensors cabling. Preliminary experiments were carried out proving the functionality of the surrogate. Results showed how multiple accelerometers and pressure sensors allowed a better comprehension of the head complex motion during impacts.

  15. Understanding human visual systems and its impact on our intelligent instruments

    Science.gov (United States)

    Strojnik Scholl, Marija; Páez, Gonzalo; Scholl, Michelle K.

    2013-09-01

    We review the evolution of machine vision and comment on the cross-fertilization from the neural sciences onto flourishing fields of neural processing, parallel processing, and associative memory in optical sciences and computing. Then we examine how the intensive efforts in mapping the human brain have been influenced by concepts in computer sciences, control theory, and electronic circuits. We discuss two neural paths that employ the input from the vision sense to determine the navigational options and object recognition. They are ventral temporal pathway for object recognition (what?) and dorsal parietal pathway for navigation (where?), respectively. We describe the reflexive and conscious decision centers in cerebral cortex involved with visual attention and gaze control. Interestingly, these require return path though the midbrain for ocular muscle control. We find that the cognitive psychologists currently study human brain employing low-spatial-resolution fMRI with temporal response on the order of a second. In recent years, the life scientists have concentrated on insect brains to study neural processes. We discuss how reflexive and conscious gaze-control decisions are made in the frontal eye field and inferior parietal lobe, constituting the fronto-parietal attention network. We note that ethical and experiential learnings impact our conscious decisions.

  16. Impact of polymer modification on mechanical and viscoelastic properties.

    Science.gov (United States)

    2015-10-01

    This study was initiated with the aim of evaluating the relative impact of different cross-linking agents : on the rheological and morphological properties of polymer modified asphalt binders (PMAs). To : complete this objective, two cross-linking ag...

  17. Mechanical response of nickel-titanium instruments with different cross-sectional designs during shaping of simulated curved canals.

    Science.gov (United States)

    Kim, H C; Kim, H J; Lee, C J; Kim, B M; Park, J K; Versluis, A

    2009-07-01

    To evaluate how different cross-sectional designs affect stress distribution in nickel-titanium (NiTi) instruments during bending, torsion and simulated shaping of a curved canal. Four NiTi rotary instruments with different cross-sectional geometries were selected: ProFile and HeroShaper systems with a common triangle-based cross section, Mtwo with an S-shaped rectangle-based design and NRT with a modified rectangle-based design. The geometries of the selected files were scanned in a micro-CT and three-dimensional finite-element models were created for each system. Stiffness characteristics for each file system were determined in a series of bending and torsional conditions. Canal shaping was simulated by inserting models of the rotating file into a 45 degrees curved canal model. Stress distribution in the instruments was recorded during simulated shaping. After the instruments were retracted from the canal, residual stresses and permanent bending of their tips due to plastic deformation were determined. The greatest bending and torsional stiffness occurred in the NRT file. During simulated shaping, the instruments with triangle-based cross-sectional geometry had more even stress distributions along their length and had lower stress concentrations than the instruments with rectangle-based cross sections. Higher residual stresses and plastic deformations were found in the Mtwo and NRT with rectangle-based cross-sectional geometries. Nickel-titanium instruments with rectangle-based cross-sectional designs created higher stress differentials during simulated canal shaping and may encounter higher residual stress and plastic deformation than instruments with triangle-based cross sections.

  18. Developing a theory-based instrument to assess the impact of continuing professional development activities on clinical practice: a study protocol

    Directory of Open Access Journals (Sweden)

    Rousseau Michel

    2011-03-01

    Full Text Available Abstract Background Continuing professional development (CPD is one of the principal means by which health professionals (i.e. primary care physicians and specialists maintain, improve, and broaden the knowledge and skills required for optimal patient care and safety. However, the lack of a widely accepted instrument to assess the impact of CPD activities on clinical practice thwarts researchers' comparisons of the effectiveness of CPD activities. Using an integrated model for the study of healthcare professionals' behaviour, our objective is to develop a theory-based, valid, reliable global instrument to assess the impact of accredited CPD activities on clinical practice. Methods Phase 1: We will analyze the instruments identified in a systematic review of factors influencing health professionals' behaviours using criteria that reflect the literature on measurement development and CPD decision makers' priorities. The outcome of this phase will be an inventory of instruments based on social cognitive theories. Phase 2: Working from this inventory, the most relevant instruments and their related items for assessing the concepts listed in the integrated model will be selected. Through an e-Delphi process, we will verify whether these instruments are acceptable, what aspects need revision, and whether important items are missing and should be added. The outcome of this phase will be a new global instrument integrating the most relevant tools to fit our integrated model of healthcare professionals' behaviour. Phase 3: Two data collections are planned: (1 a test-retest of the new instrument, including item analysis, to assess its reliability and (2 a study using the instrument before and after CPD activities with a randomly selected control group to explore the instrument's mere-measurement effect. Phase 4: We will conduct individual interviews and focus groups with key stakeholders to identify anticipated barriers and enablers for implementing the

  19. Deformation mechanisms in ferritic/martensitic steels and the impact on mechanical design

    International Nuclear Information System (INIS)

    Ghoniem, Nasr M.; Po, Giacomo; Sharafat, Shahram

    2013-01-01

    Structural steels for nuclear applications have undergone rapid development during the past few decades, thanks to a combination of trial-and-error, mechanism-based optimization, and multiscale modeling approaches. Deformation mechanisms are shown to be intimately related to mechanical design via dominant plastic deformation modes. Because mechanical design rules are mostly based on failure modes associated with plastic strain damage accumulation, we present here the fundamental deformation mechanisms for Ferritic/Martensitic (F/M) steels, and delineate their operational range of temperature and stress. The connection between deformation mechanisms, failure modes, and mechanical design is shown through application of design rules. A specific example is given for the alloy F82H utilized in the design of a Test Blanket Module (TBM) in the International Thermonuclear Experimental Reactor (ITER), where several constitutive equations are developed for design-related mechanical properties

  20. Deformation mechanisms in ferritic/martensitic steels and the impact on mechanical design

    Energy Technology Data Exchange (ETDEWEB)

    Ghoniem, Nasr M., E-mail: ghoniem@seas.ucla.edu; Po, Giacomo; Sharafat, Shahram

    2013-10-15

    Structural steels for nuclear applications have undergone rapid development during the past few decades, thanks to a combination of trial-and-error, mechanism-based optimization, and multiscale modeling approaches. Deformation mechanisms are shown to be intimately related to mechanical design via dominant plastic deformation modes. Because mechanical design rules are mostly based on failure modes associated with plastic strain damage accumulation, we present here the fundamental deformation mechanisms for Ferritic/Martensitic (F/M) steels, and delineate their operational range of temperature and stress. The connection between deformation mechanisms, failure modes, and mechanical design is shown through application of design rules. A specific example is given for the alloy F82H utilized in the design of a Test Blanket Module (TBM) in the International Thermonuclear Experimental Reactor (ITER), where several constitutive equations are developed for design-related mechanical properties.

  1. Simulation of Impacts of Changing in the International Standard of Financial Instruments (IFRS 9 in the Major Brazilian Banks

    Directory of Open Access Journals (Sweden)

    Samir Sayed

    2013-04-01

    Full Text Available This article aimed to verify the impact of changes in the net profit and their respective volatilities resulting from changes of the international standard of financial instruments, from IAS 39 to IFRS 9, in regard to aspects: (i the future change in the methodology of the impairment calculated e (ii the elimination of the category "available for sale" and their reclassification to the category "fair value through profit or loss". The study was based on simulations in profits expected to sixteen quarters, from 31/12/2010 to 31/12/2014, to the five largest financial institutions in Brazil. For such simulations it were projected interest rates that fluctuate according to the estimated model of the term structure of interest rates using the Monte Carlo method. According to the projected interest rates set new credit risk levels, which resulted changes in the impairment and fair value of financial assets previously classified as available for sale. The results showed an early impact in Q1, in view of their adaptation to the new standard. Subsequently, there was no significant change in the results and their respective volatilities.

  2. Friction Stir Weld Failure Mechanisms in Aluminum-Armor Structures Under Ballistic Impact Loading Conditions

    Science.gov (United States)

    2013-01-01

    REPORT Friction Stir Weld Failure Mechanisms in Aluminum-Armor Structures Under Ballistic Impact Loading Conditions 14. ABSTRACT 16. SECURITY...properties and of the attendant ballistic-impact failure mechanisms in prototypical friction stir welding (FSW) joints found in armor structures made of high...mechanisms, friction stir welding M. Grujicic, B. Pandurangan, A. Arakere, C-F. Yen, B. A. Cheeseman Clemson University Office of Sponsored Programs 300

  3. Formation Flying and Deformable Instruments

    International Nuclear Information System (INIS)

    Rio, Yvon

    2009-01-01

    Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and add, chopping and nodding). Formation flying disturbs this practice. It is neither possible to reduce the relative motion to very small amplitudes, nor to control it at will. Some impacts on Simbol-X instrument design, and operation are presented.

  4. Formation Flying and Deformable Instruments

    Science.gov (United States)

    Rio, Yvon

    2009-05-01

    Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and add, chopping and nodding). Formation flying disturbs this practice. It is neither possible to reduce the relative motion to very small amplitudes, nor to control it at will. Some impacts on Simbol-X instrument design, and operation are presented.

  5. Charpy impact test results on five materials and NIST verification specimens using instrumented 2-mm and 8-mm strikers

    International Nuclear Information System (INIS)

    Nanstad, R.K.; Sokolov, M.A.

    1995-01-01

    The Heavy-Section Steel Irradiation Program at Oak Ridge National Laboratory is involved in two cooperative projects, with international participants, both of which involve Charpy V-notch impact tests with instrumented strikers of 2mm and 8mm radii. Two heats of A 533 grade B class I pressure vessel steel and a low upper-shelf (LUS) submerged-arc (SA) weld were tested on the same Charpy machine, while one heat of a Russian Cr-Mo-V forging steel and a high upper-shelf (HUS) SA weld were tested on two different machines. The number of replicate tests at any one temperature ranged from 2 to 46 specimens. Prior to testing with each striker, verification specimens at the low, high, and super high energy levels from the National Institute of Standards and Technology (NIST) were tested. In the two series of verification tests, the tests with the 2mm striker met the requirements at the low and high energy levels but not at the super high energy. For one plate, the 2mm striker showed somewhat higher average absorbed energies than those for the 8-mm striker at all three test temperatures. For the second plate and the LUS weld, however, the 2mm striker showed somewhat lower energies at both test temperatures. For the Russian forging steel and the HUS weld, tests were conducted over a range of temperatures with tests at one laboratory using the 8mm striker and tests at a second laboratory using the 2mm striker. Lateral expansion was measured for all specimens and the results are compared with the absorbed energy results. The overall results showed generally good agreement (within one standard deviation) in energy measurements by the two strikers. Load-time traces from the instrumented strikers were also compared and used to estimate shear fracture percentage. Four different formulas from the European Structural Integrity Society draft standard for instrumented Charpy test are compared and a new formula is proposed for estimation of percent shear from the force-time trace

  6. Impact of Offshore Wind Energy Plants on the Soil Mechanical Behaviour of Sandy Seafloors

    Science.gov (United States)

    Stark, Nina; Lambers-Huesmann, Maria; Zeiler, Manfred; Zoellner, Christian; Kopf, Achim

    2010-05-01

    capacities (qsbc.) mainly ranging from 39 - 69 kPa (Nimrod: mass of ~ 13 kg, impact velocity of ~ 8 m/s). There was no evidence for layering in results of both in-situ instruments. After construction, most of the positions show changes in sediment strength ranging from 10 % up to 100 % compared to the results prior to windmill construction. Extreme changes (> 50 %) occur above all close to the foundations. Furthermore, patterns of relatively soft zones (qsbc.: 50 - 80 kPa) and hard zones (qsbc. > 100 kPa) were mapped during the high-resolution surveys close to the foundation. Beside that, a very soft sediment layer (0.03 - 0.05 m) drapes most of the soft zones. This may be recently eroded and re-deposited sediment, whereas the hard zones may indicate areas of sediment erosion where looser material has been carried away. Reasons for sediment remobilization and changes in geotechnical properties may be scouring as a consequence of the changed hydrodynamics in the vicinity of the windmills. Besides first developments of scour, the side scan sonar results show relicts of the wind turbine erection (e.g., footprints of jack-up-platforms). First multibeam-echosounder measurements confirm sediment re-deposition due to scour in the lee of the main current direction and show traces of wind turbine erection equipment in the same areas where also the penetrometer measurements took place. In summary, a local impact of the wind turbines on the soil mechanical properties of the seafloor is attested from this initial post-erection survey. Future cruises (every 6 months) will complement those data, which will eventually allow us a comparison to, or even refinement of long-term scouring models.

  7. Comparison of the mechanical properties of rotary instruments made of conventional nickel-titanium wire, M-wire, or nickel-titanium alloy in R-phase.

    Science.gov (United States)

    Lopes, Hélio P; Gambarra-Soares, Thaiane; Elias, Carlos N; Siqueira, José F; Inojosa, Inês F J; Lopes, Weber S P; Vieira, Victor T L

    2013-04-01

    This study compared the mechanical properties of endodontic instruments made of conventional nickel-titanium (NiTi) wire (K(3) and Revo-S SU), M-Wire (ProFile Vortex), or NiTi alloy in R-phase (K(3)XF). The test instruments were subjected to mechanical tests to evaluate resistance to bending (flexibility), cyclic fatigue, and torsional load in clockwise rotation. Data were statistically evaluated by the analysis of variance test and the Student-Newman-Keuls test for multiple comparisons. In the bending resistance test, flexibility decreased in the following order: K(3)XF > Revo-S SU > ProFile Vortex > K(3). The ranking in the fatigue resistance test was the following: K(3)XF > K(3) > ProFile Vortex > Revo-S SU. In the torsional assay, the angular deflection at failure decreased in the following order: K(3)XF > Revo-S SU > K(3) > ProFile Vortex. For the maximum torque values, the ranking was K(3) > K(3)XF > ProFile Vortex > Revo-S SU. The results showed that the K(3)XF instrument, which is made of NiTi alloy in R-phase, had the overall best performance in terms of flexibility, angular deflection at failure, and cyclic fatigue resistance. In addition to the alloy from which the instrument is manufactured, the design and dimensions are important determinants of the mechanical performance of endodontic instruments. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Mechanical Model for Dynamic Behavior of Concrete Under Impact Loading

    Science.gov (United States)

    Sun, Yuanxiang

    Concrete is a geo-material which is used substantively in the civil building and military safeguard. One coupled model of damage and plasticity to describe the complex behavior of concrete subjected to impact loading is proposed in this research work. The concrete is assumed as homogeneous continuum with pre-existing micro-cracks and micro-voids. Damage to concrete is caused due to micro-crack nucleation, growth and coalescence, and defined as the probability of fracture at a given crack density. It induces a decrease of strength and stiffness of concrete. Compaction of concrete is physically a collapse of the material voids. It produces the plastic strain in the concrete and, at the same time, an increase of the bulk modulus. In terms of crack growth model, micro-cracks are activated, and begin to propagate gradually. When crack density reaches a critical value, concrete takes place the smashing destroy. The model parameters for mortar are determined using plate impact experiment with uni-axial strain state. Comparison with the test results shows that the proposed model can give consistent prediction of the impact behavior of concrete. The proposed model may be used to design and analysis of concrete structures under impact and shock loading. This work is supported by State Key Laboratory of Explosion science and Technology, Beijing Institute of Technology (YBKT14-02).

  9. Impact mechanics of ship collisions and validations with experimental results

    DEFF Research Database (Denmark)

    Zhang, Shengming; Villavicencio, R.; Zhu, L.

    2017-01-01

    Closed-form analytical solutions for the energy released for deforming and crushing ofstructures and the impact impulse during ship collisions were developed and published inMarine Structures in 1998 [1]. The proposed mathematical models have been used bymany engineers and researchers although th...

  10. Molecular mechanism of crystallization impacting calcium phosphate cements

    Energy Technology Data Exchange (ETDEWEB)

    Giocondi, J L; El-Dasher, B S; Nancollas, G H; Orme, C A

    2009-05-31

    In summary, SPM data has shown that (1) Mg inhibits growth on all steps but relatively high Mg/Ca ratios are needed. Extracting the mechanism of interaction requires more modeling of the kinetic data, but step morphology is consistent with incorporation. (2) Citrate has several effects depending on the citrate/Ca ratio. At the lowest concentrations, citrate increases the step free energy without altering the step kinetics; at higher concentrations, the polar step is slowed. (3) Oxalate also slows the polar step but additionally stabilizes a new facet, with a [100]{sub Cc} step. (4) Etidronate has the greatest kinetic impact of the molecules studied. At 7{micro}M concentrations, the polar step slows by 60% and a new polar step appears. However, at the same time the [10-1]{sub Cc} increases by 67%. It should be noted that all of these molecules complex calcium and can effect kinetics by altering the solution supersaturation or the Ca to HPO{sub 4}{sup 2-} ratio. For the SPM data shown, this effect was corrected for to distinguish the effect of the molecule at the crystal surface from the effect of the molecule on the solution speciation. The goal of this paper is to draw connections between fundamental studies of atomic step motion and potential strategies for materials processing. It is not our intent to promote the utility of SPM for investigating processes in cement dynamics. The conditions are spectacularly different in many ways. The data shown in this paper are fairly close to equilibrium (S=1.6) whereas the nucleation of cements is initiated at supersaturation ratios in the thousands to millions. Of course, after the initial nucleation phase, the growth will occur at more modest supersaturations and as the cement evolves towards equilibrium certainly some of the growth will occur in regimes such as shown here. In addition to the difference in supersaturation, cements tend to have lower additive to calcium ratios. As an example, the additive to Ca ratio is

  11. IMPACT OF OIL ON THE MECHANICAL PROPERTIES OF SOIL SUBSIDENCE

    Directory of Open Access Journals (Sweden)

    Алексей Алексеевич Бурцев

    2016-08-01

    Full Text Available The paper studied the effect of oil content on the mechanical properties of soil subsidence - Ek modulus and compressibility factor m0, obtained in the laboratory with the help of artificial impregnation oil soil samples. A comparison of the above parameters with samples of the same soil in the natural and water-saturated conditions has been perfomed.

  12. Ozone impacts on cotton: towards an integrated mechanism

    International Nuclear Information System (INIS)

    Grantz, D.A.

    2003-01-01

    Vegetation removes tropospheric ozone (O 3 ) mainly through uptake by stomata. O 3 reduces growth, photosynthesis, and carbohydrate allocation. Effects on mesophyll photosynthesis, may reducing carbohydrate source strength and, indirectly, carbohydrate translocation. Alternatively direct translocation, itself, could explain all of these observations. O 3 -reduced root proliferation inhibits exploitation of soil resources and interferes with underground carbon sequestration. Simulations with cotton suggest O 3 -disrupted root development could indirectly reduce shoot photosynthesis. Strong evidence for O 3 impacts on both carbon assimilation and carbon translocation exists, but data determining the primacy of direct or indirect O 3 effects on either or both processes remain inconclusive. Pholoem loading may be particularly sensitive to O 3 . Further research on metabolic feedback control of carbon assimilation and phloem loading activity as affected by O 3 exposure is required. - Ozone impacts on Pima cotton are reviewed to evaluate the possibility that a direct effect on carbohydrate translocation could mediate the suite of symptoms observed

  13. Simple Tools for Surgeons : Design and Evaluation of mechanical alternatives for robotic instruments for Minimally Invasive Surgery

    NARCIS (Netherlands)

    Jaspers, J.E.N.

    2006-01-01

    Performing complex tasks in Minimally Invasive Surgery (MIS) is demanding due to a disturbed hand-eye co-ordination, the application of non-ergonomic instruments with limited number of degrees of freedom (DOFs) and the two-dimensional (2D) view controlled by the surgical assistance. Robotic camera

  14. CONTRIBUTION OF A CHOLINERGIC REFLEX MECHANISM TO ALLERGEN-INDUCED BRONCHIAL HYPERREACTIVITY IN PERMANENTLY INSTRUMENTED, UNRESTRAINED GUINEA-PIGS

    NARCIS (Netherlands)

    SANTING, RE; PASMAN, Y; OLYMULDER, CG; ROFFEL, AF; MEURS, H; ZAAGSMA, J

    1 In conscious, permanently instrumented, unrestrained, ovalbumin-sensitized guinea-pigs the development of allergen-induced bronchial hyperreactivity to histamine- and methacholine-inhalation was investigated after the early as well as after the late asthmatic response. 2 The allergen-induced

  15. Structural characterisation and mechanical FE analysis of conventional and M-Wire Ni-Ti alloys used in endodontic rotary instruments.

    Science.gov (United States)

    Montalvão, Diogo; Alçada, Francisca Sena; Braz Fernandes, Francisco Manuel; de Vilaverde-Correia, Sancho

    2014-01-01

    The purpose of this study is to understand how the M-Wire alloy conditions the mechanical flexibility of endodontic rotary files at body temperature.Two different rotary instruments, a Profile GT 20/.06 and a Profile GT Series X 20/.06, were selected due to their geometrical similarity and their different constituent alloy. GT series X files are made from M-Wire, a Ni-Ti alloy allegedly having higher flexibility at body temperature. Both files were analysed by X-Ray Diffraction and Differential Scanning Calorimetry to investigate phase transformations and the effects of working temperature on these different alloys. Mechanical behaviour was assessed by means of static bending and torsional Finite Element simulations, taking into account the nonlinear superelastic behaviour of Ni-Ti materials. It was found that GT files present austenitic phase at body temperature, whereas GT series X present R-phase at temperatures under 40 °C with a potential for larger flexibility. For the same load conditions, simulations showed that the slight geometrical differences between the two files do not introduce great disagreement in the instruments' mechanical response. It was confirmed that M-Wire increases the instrument's flexibility, mainly due to the presence of R-phase at body temperature.

  16. Reliability and construct validity of the Instrument to Measure the Impact of Valve Heart Disease on the Patient's Daily Life.

    Science.gov (United States)

    Anjos, Daniela Brianne Martins Dos; Rodrigues, Roberta Cunha Matheus; Padilha, Kátia Melissa; Pedrosa, Rafaela Batista Dos Santos; Gallani, Maria Cecília Bueno Jayme

    2016-12-19

    evaluate the practicality, acceptability and the floor and ceiling effects, estimate the reliability and verify the convergent construct's validity with the instrument called the Heart Valve Disease Impact on daily life (IDCV) of the valve disease in patients with mitral and or aortic heart valve disease. data was obtained from 86 heart valve disease patients through 3 phases: a face to face interview for a socio-demographic and clinic characterization and then other two done through phone calls of the interviewed patients for application of the instrument (test and repeat test). as for the practicality and acceptability, the instrument was applied with an average time of 9,9 minutes and with 110% of responses, respectively. Ceiling and floor effects observed for all domains, especially floor effect. Reliability was tested using the test - repeating pattern to give evidence of temporal stability of the measurement. Significant negative correlations with moderate to strong magnitude were found between the score of the generic question about the impact of the disease and the scores of IDCV, which points to the validity of the instrument convergent construct. the instrument to measure the impact of valve heart disease on the patient's daily life showed evidence of reliability and validity when applied to patients with heart valve disease. avaliar a praticabilidade, aceitabilidade e os efeitos teto e chão, estimar a confiabilidade e verificar a validade de construto convergente do Instrumento para Mensuração do Impacto da Doença no Cotidiano do Valvopata em pacientes com valvopatia mitral e/ou aórtica. dados foram obtidos junto a 86 pacientes valvopatas por meio de três etapas: uma entrevista presencial para caracterização sociodemográfica e clínica e as duas outras realizadas por meio de contato telefônico para as aplicações do instrumento (Teste e teste de repetição). quanto à praticabilidade e aceitabilidade, o instrumento foi aplicado com tempo m

  17. Mechanical Behaviour of Bolted Joints Under Impact Rates of Loading

    Science.gov (United States)

    2012-01-01

    M. (1995). Bearing Strength of Autoclave and oven cured kevlar / epoxy laminates under static and dynamic loading. Compostes, 451-456. Kretsis, G...Joints in Glass Fibre/ Epoxy Laminates. Composites, Volume 16. No 2. Kolsky, H. (1949). An Investigation of the Mechanical Properties of Materials at...elongating the pulse width. The responses are read by the strain gages bonded on the incident and transmission bar with Vishay AE-10 epoxy . The gages

  18. Cone-beam computed tomography analysis of curved root canals after mechanical preparation with three nickel-titanium rotary instruments

    Science.gov (United States)

    Elsherief, Samia M.; Zayet, Mohamed K.; Hamouda, Ibrahim M.

    2013-01-01

    Cone beam computed tomography is a 3-dimensional high resolution imaging method. The purpose of this study was to compare the effects of 3 different NiTi rotary instruments used to prepare curved root canals on the final shape of the curved canals and total amount of root canal transportation by using cone-beam computed tomography. A total of 81 mesial root canals from 42 extracted human mandibular molars, with a curvature ranging from 15 to 45 degrees, were selected. Canals were randomly divided into 3 groups of 27 each. After preparation with Protaper, Revo-S and Hero Shaper, the amount of transportation and centering ability that occurred were assessed by using cone beam computed tomography. Utilizing pre- and post-instrumentation radiographs, straightening of the canal curvatures was determined with a computer image analysis program. Canals were metrically assessed for changes (surface area, changes in curvature and transportation) during canal preparation by using software SimPlant; instrument failures were also recorded. Mean total widths and outer and inner width measurements were determined on each central canal path and differences were statistically analyzed. The results showed that all instruments maintained the original canal curvature well with no significant differences between the different files (P = 0.226). During preparation there was failure of only one file (the protaper group). In conclusion, under the conditions of this study, all instruments maintained the original canal curvature well and were safe to use. Areas of uninstrumented root canal wall were left in all regions using the various systems. PMID:23885273

  19. Mechanisms of elastic wave generation in solids by ion impact

    International Nuclear Information System (INIS)

    Deemer, B.; Murphy, J.; Claytor, T.

    1990-01-01

    This study is directed at understanding the mechanisms of acoustic signal generation by modulated beams of energetic ions as a function of ion energy. Interaction of ions with solids initiates a range of processes including sputtering, ion implantation, ionization, both internal and external, as well as thermal deposition in the solid. Accumulated internal stress also occurs by generation of dislocations resulting from, inelastic nuclear scattering of the incident ion beam. With respect to elastic wave generation, two potential mechanisms are thermoelastic induced stress and momentum transfer. The latter process includes contributions of momentum transfer from the incident beam and from ions ejected via sputtering. Other aspects of the generation process include the potential for shock wave generation since the mean particle velocity for a wide range of ion energies exceeds the velocity of sound in solids. This study seeks to distinguish the contribution of these mechanisms by studying the signature, angular distribution and energy dependence of the elastic wave response in the time domain and to use this information to understand technologically important processes such as implantation and sputtering

  20. Corino de Andrade disease: mechanisms and impact on reproduction

    Science.gov (United States)

    Lopes, Rita A; Coelho, Teresa; Barros, Alberto; Sousa, Mário

    2017-01-01

    Familial amyloid polyneuropathy was first described by Corino de Andrade in 1952 in Northern Portugal. It is a fatal autosomal dominant neurodegenerative disorder characterized by a progression of neurologic symptoms, beginning early in the reproductive life. The Transthyretin gene mutation originates a mutated protein that precipitates in the connective tissue as amyloid deposits. This disease is presently named Transthyretin-related hereditary amyloidosis. We performed an extensive review on this disease based on searches in Medical databases and in paper references. In this review, we briefly summarize the epidemiology and the mechanisms involved on amyloid deposition; we detailed how to evaluate the mechanisms implicated on the development of the major signs and symptoms associated with reproductive dysfunction; and we discuss the mechanisms involved in secondary sexual dysfunction after psychological treatments. Treatment of the disease is directed towards relieving specific symptoms in association with liver transplant, and molecular and genetic therapeutics. Although the current clinical trials indicate symptoms relief, no data on the reproductive function was reported. Thus, preimplantation genetic diagnosis is presently the only available technique that eradicates the disease as it avoids the birth of new patients. PMID:28609277

  1. The Mechanical Design of a Kinematic Mount for the Mid Infrared Instrument Focal Plane Module on the James Webb Space Telescope

    Science.gov (United States)

    Thelen, Michael P.; Moore, Donald M.

    2009-01-01

    The detector assembly for the Mid Infrared Instrument (MIRI) of the James Webb Space Telescope (JWST) is mechanically supported in the Focal Plane Module (FPM) Assembly with an efficient hexapod design. The kinematic mount design allows for precision adjustment of the detector boresight to assembly alignment fiducials and maintains optical alignment requirements during flight conditions of launch and cryogenic operations below 7 Kelvin. This kinematic mounting technique is able to be implemented in a variety of optical-mechanical designs and is capable of micron level adjustment control and stability over wide dynamic and temperature ranges.

  2. Study on the transplant impact on the elementary composition of Protousnea magellanica thallus by using instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Bubach, Debora; Guevara, Sergio Ribeiro; Arribere, Maria A.; Wiesztort, Andres; Calvelo, Susana

    1999-01-01

    As part of a study on the use of the furticose lichen Protousnea magellanica as a bio indicator of atmospheric pollution, it was studied the impact on the elemental composition of the thallus when this lichen is transplanted in the same area under similar environmental conditions. The lichens were collected and replanted in a pristine area in Puerto Blest, Nahuel Huapi National Park, Bariloche, Argentina. After one year, the transplanted thalli were collected and analyzed by using Instrumental Activation Analysis, complemented with Atomic Absorption Spectrophotometry for the Pb content determination. Crustal inputs were identified by computing enrichment factors. The transplanted thalli concentrations of most of the elements under study, Al, As, Ba, Ce, Co, Cr, Dy, Eu, Hg, Fe, La, Lu, Mn, Na, Pb, Sb, Sc, Sm, Sr, Tb, Ti, Th, V, Yb and Zn, showed no significant differences with respect to the control thalli. However, some biological elements, Ca, Cl, Br, K and Rb, showed significant variations with respect to the controls, more noticeable in the first two elements. (author)

  3. Design and Analysis of Blast Induced Traumatic Brain Injury Mechanism Using a Surrogate Headform: Instrumentation and Outcomes

    Science.gov (United States)

    2011-05-01

    www.allaboutcircuits.com) 46 [35]. This resistance change is measured using a Wheatstone bridge. A Wheatstone bridge consists of 4 resistors in two circuit...measuring the strains and the precision resistors incorporated in the measuring instrument for completing the circuit. A more symmetrical, balanced... Piezo -Electric” and defines a class of accelerometer with low impedance output and built-in electronics that works on a two-wire constant current

  4. The Role of Malware in Reported Cyber Espionage: A Review of the Impact and Mechanism

    OpenAIRE

    Gaute Wangen

    2015-01-01

    This is the journal's PDF originally published in Information, http://dx.doi.org/10.3390/info6020183 The recent emergence of the targeted use of malware in cyber espionage versus industry requires a systematic review for better understanding of its impact and mechanism. This paper proposes a basic taxonomy to document major cyber espionage incidents, describing and comparing their impacts (geographic or political targets, origins and motivations) and their mechanisms (dropper, propagation,...

  5. Defective DNA repair mechanisms in prostate cancer: impact of olaparib

    Directory of Open Access Journals (Sweden)

    De Felice F

    2017-03-01

    Full Text Available Francesca De Felice,1 Vincenzo Tombolini,1 Francesco Marampon,2 Angela Musella,3 Claudia Marchetti3 1Department of Radiotherapy, Policlinico Umberto I, “Sapienza” University of Rome, Rome, 2Department of Biotechnological and Applied Clinical Sciences, Laboratory of Radiobiology, University of L’Aquila, L’Aquila, 3Department of Gynecological and Obstetrical Sciences and Urological Sciences, “Sapienza” University of Rome, Rome, Italy Abstract: The field of prostate oncology has continued to change dramatically. It has truly become a field that is intensely linked to molecular genetic alterations, especially DNA-repair defects. Germline breast cancer 1 gene (BRCA1 and breast cancer 2 gene (BRCA2 mutations are implicated in the highest risk of prostate cancer (PC predisposition and aggressiveness. Poly adenosine diphosphate ribose polymerase (PARP proteins play a key role in DNA repair mechanisms and represent a valid target for new therapies. Olaparib is an oral PARP inhibitor that blocks DNA repair pathway and coupled with BRCA mutated-disease results in tumor cell death. In phase II clinical trials, including patients with advanced castration-resistant PC, olaparib seems to be efficacious and well tolerated. Waiting for randomized phase III trials, olaparib should be considered as a promising treatment option for PC. Keywords: prostate cancer, metastatic disease, castration resistant, BRCA, DNA-repair, PARP, olaparib

  6. Development of the Pulmonary Arterial Hypertension-Symptoms and Impact (PAH-SYMPACT®) questionnaire: a new patient-reported outcome instrument for PAH.

    Science.gov (United States)

    McCollister, Deborah; Shaffer, Shannon; Badesch, David B; Filusch, Arthur; Hunsche, Elke; Schüler, René; Wiklund, Ingela; Peacock, Andrew

    2016-06-14

    Regulators and clinical experts increasingly recognize the importance of incorporating patient-reported outcomes (PROs) in clinical studies of therapies for pulmonary arterial hypertension (PAH). No PAH-specific instruments have been developed to date in accordance with the 2009 FDA guidance for the development of PROs as endpoints in clinical trials. A qualitative research study was conducted to develop a new instrument assessing PAH symptoms and their impacts following the FDA PRO guidance. A cross-sectional study was conducted at 5 centers in the US in symptomatic PAH patients aged 18-80 years. Concept elicitation was based on 5 focus group discussions, after which saturation of emergent concepts was reached. A PRO instrument for PAH symptoms and their impacts was drafted. To assess the appropriateness of items, instructions, response options, and recall periods, 2 rounds of one-on-one cognitive interviews were conducted, with instrument revisions following each round. Additional interviews tested the usability of an electronic version (ePRO). PRO development considered input from an international Steering Committee, and translatability and lexibility assessments. Focus groups comprised 25 patients (5 per group); 20 additional patients participated in cognitive interviews (10 per round); and 10 participated in usability interviews. Participants had a mean ± SD age of 53.1 ± 15.8 years, were predominantly female (93 %), and were diverse in race/ethnicity, WHO functional class (FC I/II: 56 %, III/IV: 44 %), and PAH etiology (idiopathic: 56 %, familial: 2 %, associated: 42 %). The draft PRO instrument (PAH-SYMPACT®) was found to be clear, comprehensive, and relevant to PAH patients in cognitive interviews. Items were organized in a draft conceptual framework with 16 symptom items in 4 domains (respiratory symptoms, tiredness, cardiovascular symptoms, other symptoms) and 25 impact items in 5 domains (physical activities, daily activities, social

  7. THE IMPACT OF A MECHANICAL PRESS ON THE ACCURACY OF PRODUCTS IN COLD FORGING

    DEFF Research Database (Denmark)

    Krusic, V.; Arentoft, Mogens; Rodic, T.

    2005-01-01

    Cold extrusion is an economic production process for the production of elements of complex forms and accurate dimensions. The first part of the article explains the impact that a mechanical press has on the accuracy of products. It describes the mechanical press main characteristics and in additi...

  8. Mechanical anomaly impact on metal-oxide-semiconductor capacitors on flexible silicon fabric

    KAUST Repository

    Ghoneim, Mohamed T.; Kutbee, Arwa T.; Ghodsi Nasseri, Seyed Faizelldin; Bersuker, G.; Hussain, Muhammad Mustafa

    2014-01-01

    We report the impact of mechanical anomaly on high-κ/metal-oxide-semiconductor capacitors built on flexible silicon (100) fabric. The mechanical tests include studying the effect of bending radius up to 5 mm minimum bending radius with respect

  9. Electro-mechanical impact system excited by a source of limited power

    Czech Academy of Sciences Publication Activity Database

    Půst, Ladislav

    2008-01-01

    Roč. 15, č. 6 (2008), s. 1-10 ISSN 1802-1484 R&D Projects: GA ČR GA101/06/0063 Institutional research plan: CEZ:AV0Z20760514 Keywords : mechanical oscillations * impacts * limited power of exciter * electro-mechanical interaction Subject RIV: BI - Acoustics

  10. Impact initiation of explosives and propellants via statistical crack mechanics

    Science.gov (United States)

    Dienes, J. K.; Zuo, Q. H.; Kershner, J. D.

    2006-06-01

    A statistical approach has been developed for modeling the dynamic response of brittle materials by superimposing the effects of a myriad of microcracks, including opening, shear, growth and coalescence, taking as a starting point the well-established theory of penny-shaped cracks. This paper discusses the general approach, but in particular an application to the sensitivity of explosives and propellants, which often contain brittle constituents. We examine the hypothesis that the intense heating by frictional sliding between the faces of a closed crack during unstable growth can form a hot spot, causing localized melting, ignition, and fast burn of the reactive material adjacent to the crack. Opening and growth of a closed crack due to the pressure of burned gases inside the crack and interactions of adjacent cracks can lead to violent reaction, with detonation as a possible consequence. This approach was used to model a multiple-shock experiment by Mulford et al. [1993. Initiation of preshocked high explosives PBX-9404, PBX-9502, PBX-9501, monitored with in-material magnetic gauging. In: Proceedings of the 10th International Detonation Symposium, pp. 459-467] involving initiation and subsequent quenching of chemical reactions in a slab of PBX 9501 impacted by a two-material flyer plate. We examine the effects of crack orientation and temperature dependence of viscosity of the melt on the response. Numerical results confirm our theoretical finding [Zuo, Q.H., Dienes, J.K., 2005. On the stability of penny-shaped cracks with friction: the five types of brittle behavior. Int. J. Solids Struct. 42, 1309-1326] that crack orientation has a significant effect on brittle behavior, especially under compressive loading where interfacial friction plays an important role. With a reasonable choice of crack orientation and a temperature-dependent viscosity obtained from molecular dynamics calculations, the calculated particle velocities compare well with those measured using

  11. Observational Cosmology with the Planck satellite: extraction of the astrophysical signal from raw data of HFI instrument and study of the impact of cosmic rays

    International Nuclear Information System (INIS)

    Girard, D.

    2010-01-01

    Cosmology is a very old science. It's goal is to describe the Universe at large scales. The standard model of cosmology is an inflation-CDM Big-Bang model. It is based on General Relativity. The cosmic microwave background is one of the three pillars of this model, with the expansion of the Universe and the primordial nucleosynthesis. It is the oldest detectable radiation in the Universe. The study of its temperature and polarisation anisotropies allow us to access direct information about the content and the geometry of the primordial Universe. The Planck satellite, launched on May 14 of 2009, represents the third generation of satellite missions which study the cosmic microwave background. The exceptional sensitivity of its instruments, High Frequency Instrument and Low Frequency Instrument, will allow us to constrain very strongly the cosmological models describing the early Universe, particularly the inflationary period, and to measure the cosmological parameters which describe the evolution of the Universe with an accuracy down to the percent. To reach these ambitious scientific objectives, each systematic instrumental effect has to be severely controlled and corrected by the data analysis. The effect of cosmic rays interacting with the bolometers of HFI, which is one of the most important effects, and which differs significatively from predictions, is corrected during the time ordered data analysis. The detailed understanding of this phenomenon and its modeling are necessary to correct it and to reach an optimal effective sensitivity. They will permit to take this effect into account in the conception of the future instruments detectors. This thesis proposes a first part focused on cosmology, a second part describing the Planck satellite, the HFI instrument and particularly its detectors and a third part dedicated to the HFI instrument data analysis. I concentrate on time ordered data analysis and on the corrections of instrumental systematic effects. Then I

  12. IMPACT OF REFLEXOLOGY ON MECHANICAL LOW BACK PAIN

    Directory of Open Access Journals (Sweden)

    Salwa El-Gendy

    2015-10-01

    Full Text Available Background: Low-back pain (LBP is one of the highest common and costly musculoskeletal conditions in current society. Seventy to 85% of the populations will exhibits LBP at some time in their lives. There is little known about specific manual therapy techniques used to treat chronic LBP. Reflexology is a treatment that involves using gentle pressure to reflex points located on all of the outsides of the feet and hands. The aim of the study was to investigate the efficacy of reflexology technique in subjects with chronic low back pain (CLBP. Methods: Twenty patients with nonspecific chronic low back pain were included in the study and were assessed regarding range of motion via goniometer and pain threshold (via modified Oswestery scale and visual analogue scale, the 20 patients were allocated into two groups 10 patients in each group. Group A received reflexology sittings at rate of 3 days per week, and the duration of each sitting was 30 minutes. While group B were control. The study was continued for 3 weeks Results: According to VAS, the results revealed a non-significant variance between the study group and control group before intervention (p= 0.43. While after intervention, there was a significant decline of pain in the study group compared to that of the control group (p=0.000. Moreover, there was a very highly significant decrease in pain within the study group after treatment (p= 0.005. Conclusion: The present study indicated that the reflexology technique was effective and safe to be applied for cases of mechanical low back pain. It results in a significant decrease in pain within the study group after treatment.

  13. Mechanical anomaly impact on metal-oxide-semiconductor capacitors on flexible silicon fabric

    KAUST Repository

    Ghoneim, Mohamed T.

    2014-06-09

    We report the impact of mechanical anomaly on high-κ/metal-oxide-semiconductor capacitors built on flexible silicon (100) fabric. The mechanical tests include studying the effect of bending radius up to 5 mm minimum bending radius with respect to breakdown voltage and leakage current of the devices. We also report the effect of continuous mechanical stress on the breakdown voltage over extended periods of times.

  14. Computational contact and impact mechanics fundamentals of modeling interfacial phenomena in nonlinear finite element analysis

    CERN Document Server

    Laursen, Tod A

    2003-01-01

    This book comprehensively treats the formulation and finite element approximation of contact and impact problems in nonlinear mechanics. Intended for students, researchers and practitioners interested in numerical solid and structural analysis, as well as for engineers and scientists dealing with technologies in which tribological response must be characterized, the book includes an introductory but detailed overview of nonlinear finite element formulations before dealing with contact and impact specifically. Topics encompassed include the continuum mechanics, mathematical structure, variational framework, and finite element implementations associated with contact/impact interaction. Additionally, important and currently emerging research topics in computational contact mechanics are introduced, encompassing such topics as tribological complexity, conservative treatment of inelastic impact interaction, and novel spatial discretization strategies.

  15. Effect of processing conditions on the mechanical and thermal properties of high-impact polypropylene nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Furlan, L G [Federal Institute of Rio Grande do Sul, IFRS, Campus Restinga, Estrada Joao Antonio da Silveira, 351, Porto Alegre 91790-400 (Brazil); Ferreira, C I; Dal Castel, C; Santos, K S; Mello, A C.E. [Chemistry Institute, Federal University of Rio Grande do Sul, UFRGS, Av. Bento Goncalves, 9500, Porto Alegre 91501-970 (Brazil); Liberman, S A; Oviedo, M A.S. [Braskem S.A., III Polo Petroquimico, Via Oeste, Lote 5, Triunfo 95853-000 (Brazil); Mauler, R.S., E-mail: mauler@iq.ufrgs.br [Chemistry Institute, Federal University of Rio Grande do Sul, UFRGS, Av. Bento Goncalves, 9500, Porto Alegre 91501-970 (Brazil)

    2011-08-25

    Highlights: {yields} Polypropylene montmorillonite (PP-MMT) produced at different processing conditions. {yields} Polypropylene Nanocomposites with higher increase on impact resistance. {yields} Higher enhancement on mechanical properties. - Abstract: Polypropylene montmorillonite (PP-MMT) nanocomposites have been prepared by using a co-rotating twin screw extruder. The effects of processing conditions at fixed clay content (5 wt%) on polymer properties were investigated by means of transmission electron microscopy (TEM), flexural modulus, izod impact, dynamic mechanical analysis (DMA), and differential scanning calorimetry (DSC). It was noticed that the morphology and the mechanical properties of polypropylene nanocomposites were affected by different screw shear configuration. The results showed that the higher enhancement on mechanical properties was obtained by medium shear intensity profile instead of high configuration. An exceptional increase (maximum of 282%) on impact resistance was observed.

  16. Effect of processing conditions on the mechanical and thermal properties of high-impact polypropylene nanocomposites

    International Nuclear Information System (INIS)

    Furlan, L.G.; Ferreira, C.I.; Dal Castel, C.; Santos, K.S.; Mello, A.C.E.; Liberman, S.A.; Oviedo, M.A.S.; Mauler, R.S.

    2011-01-01

    Highlights: → Polypropylene montmorillonite (PP-MMT) produced at different processing conditions. → Polypropylene Nanocomposites with higher increase on impact resistance. → Higher enhancement on mechanical properties. - Abstract: Polypropylene montmorillonite (PP-MMT) nanocomposites have been prepared by using a co-rotating twin screw extruder. The effects of processing conditions at fixed clay content (5 wt%) on polymer properties were investigated by means of transmission electron microscopy (TEM), flexural modulus, izod impact, dynamic mechanical analysis (DMA), and differential scanning calorimetry (DSC). It was noticed that the morphology and the mechanical properties of polypropylene nanocomposites were affected by different screw shear configuration. The results showed that the higher enhancement on mechanical properties was obtained by medium shear intensity profile instead of high configuration. An exceptional increase (maximum of 282%) on impact resistance was observed.

  17. Problems with radiological surveillance instrumentation

    International Nuclear Information System (INIS)

    Swinth, K.L.; Tanner, J.E.; Fleming, D.M.

    1984-09-01

    Many radiological surveillance instruments are in use at DOE facilities throughout the country. These instruments are an essential part of all health physics programs, and poor instrument performance can increase program costs or compromise program effectiveness. Generic data from simple tests on newly purchased instruments shows that many instruments will not meet requirements due to manufacturing defects. In other cases, lack of consideration of instrument use has resulted in poor acceptance of instruments and poor reliability. The performance of instruments is highly variable for electronic and mechanical performance, radiation response, susceptibility to interferences and response to environmental factors. Poor instrument performance in these areas can lead to errors or poor accuracy in measurements

  18. Problems with radiological surveillance instrumentation

    International Nuclear Information System (INIS)

    Swinth, K.L.; Tanner, J.E.; Fleming, D.M.

    1985-01-01

    Many radiological surveillance instruments are in use at DOE facilities throughout the country. These instruments are an essential part of all health physics programs, and poor instrument performance can increase program costs or compromise program effectiveness. Generic data from simple tests on newly purchased instruments shows that many instruments will not meet requirements due to manufacturing defects. In other cases, lack of consideration of instrument use has resulted in poor acceptance of instruments and poor reliability. The performance of instruments is highly variable for electronic and mechanical performance, radiation response, susceptibility to interferences and response to environmental factors. Poor instrument performance in these areas can lead to errors or poor accuracy in measurements

  19. Papua New Guinea vision-specific quality of life questionnaire: a new patient-reported outcome instrument to assess the impact of impaired vision.

    Science.gov (United States)

    Paudel, Prakash; Khadka, Jyoti; Burnett, Anthea; Hani, Yvonne; Naduvilath, Thomas; Fricke, Tim R

    2015-04-01

    The aim of this study was to develop and validate a new vision-specific quality of life (VS QoL) instrument and to assess the impact of vision impairment and eye disease on the quality of life of adults in Papua New Guinea (PNG). This study was designed as community based cross-sectional. Six hundred fourteen adults aged 18 and above were included in this study. Focus groups and interviews guided development of a 41-item instrument. Two valid subscales of the instrument were obtained using pilot data after an iterative item reduction process guided by Rasch-based parameters. The person measures (in logits) of 614 participants were used to assess quality of life using univariate and multivariate regression analysis. Rasch logits. Rasch analysis confirmed a 17-item instrument containing an 8-item activity limitation subscale and a 9-item well-being subscale. Both subscales were unidimensional and demonstrated good fit statistics, measurement precisions and absence of significant differential item functioning. A consistent deterioration in vision-specific quality of life was independently and significantly associated with levels of vision. Severity of vision impairment and ocular morbidity were independently associated with activity limitation and emotional well-being. Participants with refractive error had lower quality of life score than those with no ocular abnormality but higher score than those with cataract and other eye diseases. The 17-item PNG-VS QoL instrument is a valid and reliable instrument for the assessment of impact of impaired vision on quality of life in PNG. Vision-specific quality of life was significantly worse among participants who were older and less-educated, had lower income and have had ocular morbidities. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

  20. Development of a simple 12-item theory-based instrument to assess the impact of continuing professional development on clinical behavioral intentions.

    Directory of Open Access Journals (Sweden)

    France Légaré

    Full Text Available Decision-makers in organizations providing continuing professional development (CPD have identified the need for routine assessment of its impact on practice. We sought to develop a theory-based instrument for evaluating the impact of CPD activities on health professionals' clinical behavioral intentions.Our multipronged study had four phases. 1 We systematically reviewed the literature for instruments that used socio-cognitive theories to assess healthcare professionals' clinically-oriented behavioral intentions and/or behaviors; we extracted items relating to the theoretical constructs of an integrated model of healthcare professionals' behaviors and removed duplicates. 2 A committee of researchers and CPD decision-makers selected a pool of items relevant to CPD. 3 An international group of experts (n = 70 reached consensus on the most relevant items using electronic Delphi surveys. 4 We created a preliminary instrument with the items found most relevant and assessed its factorial validity, internal consistency and reliability (weighted kappa over a two-week period among 138 physicians attending a CPD activity. Out of 72 potentially relevant instruments, 47 were analyzed. Of the 1218 items extracted from these, 16% were discarded as improperly phrased and 70% discarded as duplicates. Mapping the remaining items onto the constructs of the integrated model of healthcare professionals' behaviors yielded a minimum of 18 and a maximum of 275 items per construct. The partnership committee retained 61 items covering all seven constructs. Two iterations of the Delphi process produced consensus on a provisional 40-item questionnaire. Exploratory factorial analysis following test-retest resulted in a 12-item questionnaire. Cronbach's coefficients for the constructs varied from 0.77 to 0.85.A 12-item theory-based instrument for assessing the impact of CPD activities on health professionals' clinical behavioral intentions showed adequate validity and

  1. Precision mechanical structure of an ultra-high-resolution spectrometer for inelastic X-ray scattering instrument

    Science.gov (United States)

    Shu, Deming; Shvydko, Yuri; Stoupin, Stanislav A.; Khachatryan, Ruben; Goetze, Kurt A.; Roberts, Timothy

    2015-04-14

    A method and an ultrahigh-resolution spectrometer including a precision mechanical structure for positioning inelastic X-ray scattering optics are provided. The spectrometer includes an X-ray monochromator and an X-ray analyzer, each including X-ray optics of a collimating (C) crystal, a pair of dispersing (D) element crystals, anomalous transmission filter (F) and a wavelength (W) selector crystal. A respective precision mechanical structure is provided with the X-ray monochromator and the X-ray analyzer. The precision mechanical structure includes a base plate, such as an aluminum base plate; positioning stages for D-crystal alignment; positioning stages with an incline sensor for C/F/W-crystal alignment, and the positioning stages including flexure-based high-stiffness structure.

  2. Scanning electron microscopic evaluation of the influence of manual and mechanical glide path on the surface of nickel-titanium rotary instruments in moderately curved root canals: An in-vivo study

    Science.gov (United States)

    Patel, Dishant; Bashetty, Kusum; Srirekha, A.; Archana, S.; Savitha, B.; Vijay, R.

    2016-01-01

    Aim: The aim of this study was to evaluate the influence of manual versus mechanical glide path (GP) on the surface changes of two different nickel-titanium rotary instruments used during root canal therapy in a moderately curved root canal. Materials and Methods: Sixty systemically healthy controls were selected for the study. Controls were divided randomly into four groups: Group 1: Manual GP followed by RaCe rotary instruments, Group 2: Manual GP followed by HyFlex rotary instruments, Group 3: Mechanical GP followed by RaCe rotary instruments, Group 4: Mechanical GP followed by HyFlex rotary instruments. After access opening, GP was prepared and rotary instruments were used according to manufacturer's instructions. All instruments were evaluated for defects under standard error mean before their use and after a single use. The scorings for the files were given at apical and middle third. Statistical Analysis Used: Chi-squared test was used. Results: The results showed that there is no statistical difference between any of the groups. Irrespective of the GP and rotary files used, more defects were present in the apical third when compared to middle third of the rotary instrument. Conclusion: Within the limitations of this study, it can be concluded that there was no effect of manual or mechanical GP on surface defects of subsequent rotary file system used. PMID:27994317

  3. Vertical force and torque analysis during mechanical preparation of extracted teeth using hand ProTaper instruments.

    Science.gov (United States)

    Glavičić, Snježana; Anić, Ivica; Braut, Alen; Miletić, Ivana; Borčić, Josipa

    2011-08-01

    The purpose was to measure and analyse the vertical force and torque developed in the wider and narrower root canals during hand ProTaper instrumentation. Twenty human incisors were divided in two groups. Upper incisors were experimental model for the wide, while the lower incisors for the narrow root canals. Measurements of the force and torque were done by a device constructed for this purpose. Differences between the groups were statistically analysed by Mann-Whitney U-test with the significance level set to P<0.05. Vertical force in the upper incisors ranged 0.25-2.58 N, while in the lower incisors 0.38-6.94 N. Measured torque in the upper incisors ranged 0.53-12.03 Nmm, while in the lower incisor ranged 0.94-10.0 Nmm. Vertical force and torque were higher in the root canals of smaller diameter. The increase in the contact surface results in increase of the vertical force and torque as well in both narrower and wider root canals. © 2010 The Authors. Australian Endodontic Journal © 2010 Australian Society of Endodontology.

  4. Public Policy Instruments and Their Impact: From Analogue to Electronic Government in the Bus Services of São Paulo

    Directory of Open Access Journals (Sweden)

    Marcos Lopes Campos

    2018-04-01

    Full Text Available This article deals with the relations between public policy instruments and production practices of objects related to government action. It demonstrates that the materiality of the instruments built to make a public policy object legible to its operators has independent effects on the relations among private operators, bureaucrats, and the public sector. Based on the bus service provision policies in the city of São Paulo between the 1980s and the 2000s, it shows that transportation policies are structured around the dilemmas and conflicts associated with the production of reports and databases. This article suggests that everyday practices and instruments, especially those associated with the documentation of operational performance, are key dimensions to understand the limits and potential of both state capacities and the regulation of companies’ profits. Because of its materiality, documentation practices and document pathways, operate as devices and artifacts which structure opacities, asymmetries of information, and power struggles between the state bureaucrats and private companies in the construction of service legibility. This article concludes that the transition from the governance through analogue instruments to the governance through electronic instruments is characterized by more transparency and greater regulatory potential over the private sector.

  5. “Lock-in” effect of emission standard and its impact on the choice of market based instruments

    International Nuclear Information System (INIS)

    Haoqi, Qian; Libo, Wu; Weiqi, Tang

    2017-01-01

    A country's existing emission standard policy will lead to a “lock in” effect. When the country plans to adopt new market-based instruments to control greenhouse gas emissions, it must consider this effect as it chooses among instruments to avoid larger efficiency loss. In this paper, we find that the “lock in” effect will cause a kink point to occur on the marginal abatement cost (MAC) curve. This change of shape for the MAC curve reminds us to be cautious in choosing market-based instruments when applying Weitzman's rule. We also introduce this concept into a dynamic multi-regional computable general equilibrium (CGE) model for China and simulate MAC curves for all regions. After applying Weitzman's rule, we propose a timeline for introducing price instruments under different marginal benefit (MB) curve scenarios. - Highlights: • China's existing carbon intensity policy has a “lock-in” effect and leads to a “kink point” on MAC. • A dynamic inter-regional CGE model is developed to simulate the regional kinked MAC curves in China. • A timeline of introducing new market based instrument is proposed by combining different MB scenarios.

  6. On the Impact of Intraluminal Thrombus Mechanical Behavior in AAA Passive Mechanics.

    Science.gov (United States)

    Riveros, Fabián; Martufi, Giampaolo; Gasser, T Christian; Rodriguez-Matas, Jose F

    2015-09-01

    Intraluminal thrombus (ILT) is a pseudo-tissue that develops from coagulated blood, and is found in most abdominal aortic aneurysms (AAAs) of clinically relevant size. A number of studies have suggested that ILT mechanical characteristics may be related to AAA risk of rupture, even though there is still great controversy in this regard. ILT is isotropic and inhomogeneous and may appear as a soft (single-layered) or stiff (multilayered fibrotic) tissue. This paper aims to investigate how ILT constitution and topology influence the magnitude and location of peak wall stress (PWS). In total 21 patient-specific AAAs (diameter 4.2-5.4 cm) were reconstructed from computer tomography images and biomechanically analyzed using state-of-the-art modeling assumptions. Results indicated that PWS correlated stronger with ILT volume (ρ = 0.44, p = 0.05) and minimum thickness of ILT layer (ρ = 0.73, p = 0.001) than with maximum AAA diameter (ρ = 0.05, p = 0.82). On average PWS was 20% (SD 12%) higher for FE models that used soft instead of stiff ILT models (p AAA diameter and was independent from ILT stiffness. In addition, ILT heterogeneity, i.e., the spatial composition of soft and stiff thrombus tissue, can considerably influence stress in the AAA wall. The present study is limited to identification of influential biomechanical factors, and how its findings translate to an AAA rupture risk assessment remains to be explored by clinical studies.

  7. Disentangling the Impact of Control-Enhancing Mechanisms on Firm Performance

    DEFF Research Database (Denmark)

    Zattoni, Alessandro; Pedersen, Torben

    2011-01-01

    shareholders to expropriate minority shareholders. The aim of this article is to contribute to the current debate investigating the implications of these control-enhancing mechanisms on firm performance. To reach this purpose, we collected ownership data on the (100) largest listed companies per capitalization......Governance scholars and investors traditionally advocate against the use of control enhancing mechanisms, i.e. mechanisms aimed at separating voting and cash flow rights. These mechanisms may, in fact, determine a deviation from the proportionality principle and may encourage large and controlling...... in five European countries (i.e. France, Germany, Italy, Spain, and the UK). Then we tested the consequences of control-enhancing mechanisms for firm performance using 2SLS regression models. Our results show that (i) mechanisms that lock-in control do have a direct and negative impact on firm performance...

  8. Mechanisms and risk of cumulative impacts to coastal ecosystem services: An expert elicitation approach

    KAUST Repository

    Singh, Gerald G.

    2017-05-23

    approaches like this to understand mechanisms of impact, in order to develop strategies to manage them.

  9. Mechanisms and risk of cumulative impacts to coastal ecosystem services: An expert elicitation approach.

    Science.gov (United States)

    Singh, Gerald G; Sinner, Jim; Ellis, Joanne; Kandlikar, Milind; Halpern, Benjamin S; Satterfield, Terre; Chan, Kai M A

    2017-09-01

    like this to understand mechanisms of impact, in order to develop strategies to manage them. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Skeletal muscle contraction in protecting joints and bones by absorbing mechanical impacts

    Science.gov (United States)

    Rudenko, O. V.; Tsyuryupa, S.; Sarvazyan, A.

    2016-09-01

    We have previously hypothesized that the dissipation of mechanical energy of external impact is a fundamental function of skeletal muscle in addition to its primary function to convert chemical energy into mechanical energy. In this paper, a mathematical justification of this hypothesis is presented. First, a simple mechanical model, in which the muscle is considered as a simple Hookean spring, is considered. This analysis serves as an introduction to the consideration of a biomechanical model taking into account the molecular mechanism of muscle contraction, kinetics of myosin bridges, sarcomere dynamics, and tension of muscle fibers. It is shown that a muscle behaves like a nonlinear and adaptive spring tempering the force of impact and increasing the duration of the collision. The temporal profiles of muscle reaction to the impact as functions of the levels of muscle contraction, durations of the impact front, and the time constants of myosin bridges closing, are obtained. The absorption of mechanical shock energy is achieved due to the increased viscoelasticity of the contracting skeletal muscle. Controlling the contraction level allows for the optimization of the stiffness and viscosity of the muscle necessary for the protection of the joints and bones.

  11. Analysing the interactions between renewable energy promotion and energy efficiency support schemes: The impact of different instruments and design elements

    International Nuclear Information System (INIS)

    Rio, Pablo del

    2010-01-01

    CO 2 emissions reduction, renewable energy deployment and energy efficiency are three main energy/environmental goals, particularly in Europe. Their relevance has led to the implementation of support schemes in these realms. Their coexistence may lead to overlaps, synergies and conflicts between them. The aim of this paper is to analyse the interactions between energy efficiency measures and renewable energy promotion, whereas previous analyses have focused on the interactions between emissions trading schemes (ETS) and energy efficiency measures and ETS and renewable energy promotion schemes. Furthermore, the analysis in this paper transcends the 'certificate' debate (i.e., tradable green and white certificates) and considers other instruments, particularly feed-in tariffs for renewable electricity. The goal is to identify positive and negative interactions between energy efficiency and renewable electricity promotion and to assess whether the choice of specific instruments and design elements within those instruments affects the results of the interactions.

  12. Analysing the interactions between renewable energy promotion and energy efficiency support schemes: The impact of different instruments and design elements

    Energy Technology Data Exchange (ETDEWEB)

    Rio, Pablo del, E-mail: pablo.delrio@cchs.csic.e [Instituto de Politicas y Bienes Publicos, Consejo Superior de Investigaciones Cientificas (CSIC), C/Albasanz 26-28, 28037 Madrid (Spain)

    2010-09-15

    CO{sub 2} emissions reduction, renewable energy deployment and energy efficiency are three main energy/environmental goals, particularly in Europe. Their relevance has led to the implementation of support schemes in these realms. Their coexistence may lead to overlaps, synergies and conflicts between them. The aim of this paper is to analyse the interactions between energy efficiency measures and renewable energy promotion, whereas previous analyses have focused on the interactions between emissions trading schemes (ETS) and energy efficiency measures and ETS and renewable energy promotion schemes. Furthermore, the analysis in this paper transcends the 'certificate' debate (i.e., tradable green and white certificates) and considers other instruments, particularly feed-in tariffs for renewable electricity. The goal is to identify positive and negative interactions between energy efficiency and renewable electricity promotion and to assess whether the choice of specific instruments and design elements within those instruments affects the results of the interactions.

  13. Analysing the interactions between renewable energy promotion and energy efficiency support schemes. The impact of different instruments and design elements

    Energy Technology Data Exchange (ETDEWEB)

    Del Rio, Pablo [Instituto de Politicas y Bienes Publicos, Consejo Superior de Investigaciones Cientificas (CSIC), C/Albasanz 26-28, 28037 Madrid (Spain)

    2010-09-15

    CO{sub 2} emissions reduction, renewable energy deployment and energy efficiency are three main energy/environmental goals, particularly in Europe. Their relevance has led to the implementation of support schemes in these realms. Their coexistence may lead to overlaps, synergies and conflicts between them. The aim of this paper is to analyse the interactions between energy efficiency measures and renewable energy promotion, whereas previous analyses have focused on the interactions between emissions trading schemes (ETS) and energy efficiency measures and ETS and renewable energy promotion schemes. Furthermore, the analysis in this paper transcends the certificate debate (i.e., tradable green and white certificates) and considers other instruments, particularly feed-in tariffs for renewable electricity. The goal is to identify positive and negative interactions between energy efficiency and renewable electricity promotion and to assess whether the choice of specific instruments and design elements within those instruments affects the results of the interactions. (author)

  14. Failure mechanism of monolayer graphene under hypervelocity impact of spherical projectile

    Science.gov (United States)

    Xia, Kang; Zhan, Haifei; Hu, De'An; Gu, Yuantong

    2016-09-01

    The excellent mechanical properties of graphene have enabled it as appealing candidate in the field of impact protection or protective shield. By considering a monolayer graphene membrane, in this work, we assessed its deformation mechanisms under hypervelocity impact (from 2 to 6 km/s), based on a serial of in silico studies. It is found that the cracks are formed preferentially in the zigzag directions which are consistent with that observed from tensile deformation. Specifically, the boundary condition is found to exert an obvious influence on the stress distribution and transmission during the impact process, which eventually influences the penetration energy and crack growth. For similar sample size, the circular shape graphene possesses the best impact resistance, followed by hexagonal graphene membrane. Moreover, it is found the failure shape of graphene membrane has a strong relationship with the initial kinetic energy of the projectile. The higher kinetic energy, the more number the cracks. This study provides a fundamental understanding of the deformation mechanisms of monolayer graphene under impact, which is crucial in order to facilitate their emerging future applications for impact protection, such as protective shield from orbital debris for spacecraft.

  15. Apical instrumentation in endodontic therapy

    Directory of Open Access Journals (Sweden)

    Kurniasri Darliana

    2007-07-01

    Full Text Available Cleaning and shaping of the root canal as the foundation for successful endodontic therapy. Cleaning of the root canal as the removal of all the contents of the root canal systems before and during shaping. Mechanical cleaning as the most important part of the root canal therapy. Instrumentation of the apical region has long been considered to be an essential component in the cleaning and shaping process. The apical area as the critical zone for instrumentation. The apical portion of the root canal system can retain microorganisms that could potentially cause periradicular inflammation. The nickel-titanium rotary instrumentation system to facilitate the cleaning and shaping process. Larger instrumentation sizes not only allow proper irrigation but also significantly decrease remaining bacteria in the canal system. How the larger apical sizes preparation must be achieved to clinical success. This paper will describe the major factors impacting the selection of final apical size, the factors are the anatomy of the apical constriction, root canal diameter, apical instrumentation, and bacteria in dentin tubuli.

  16. Radioisotope instruments

    CERN Document Server

    Cameron, J F; Silverleaf, D J

    1971-01-01

    International Series of Monographs in Nuclear Energy, Volume 107: Radioisotope Instruments, Part 1 focuses on the design and applications of instruments based on the radiation released by radioactive substances. The book first offers information on the physical basis of radioisotope instruments; technical and economic advantages of radioisotope instruments; and radiation hazard. The manuscript then discusses commercial radioisotope instruments, including radiation sources and detectors, computing and control units, and measuring heads. The text describes the applications of radioisotop

  17. Investigating the Impact of Formal Reflective Activities on Skill Adaptation in a Work-Related Instrumental Learning Setting

    Science.gov (United States)

    Roessger, Kevin M.

    2013-01-01

    In work-related, instrumental learning contexts the role of reflective activities is unclear. Kolb's (1985) experiential learning theory and Mezirow's transformative learning theory (2000) predict skill-adaptation as a possible outcome. This prediction was experimentally explored by manipulating reflective activities and assessing participants'…

  18. The Impact of Chronic Skin Disease on Daily Life (ISDL): a generic and dermatology-specific health instrument.

    NARCIS (Netherlands)

    Evers, A.W.M.; Duller, P.; Kerkhof, P.C.M. van de; Valk, P.G.M. van der; Jong, E.M.G.J. de; Gerritsen, M.J.P.; Otero, E.; Verhoeven, E.W.M.; Verhaak, C.M.; Kraaimaat, F.W.

    2008-01-01

    BACKGROUND: In dermatological research and clinical practice, there is a need for comprehensive self-report instruments that assess a broad spectrum of health implications of chronic skin diseases, including generic and skin-specific aspects of disease-related quality of life. The advantages of

  19. Impact of the Atlantic Multidecadal Oscillation (AMO) on deriving anthropogenic warming rates from the instrumental temperature record

    NARCIS (Netherlands)

    van der Werf, G.R.; Dolman, A.J.

    2014-01-01

    The instrumental surface air temperature record has been used in several statistical studies to assess the relative role of natural and anthropogenic drivers of climate change. The results of those studies varied considerably, with anthropogenic temperature trends over the past 25-30 years suggested

  20. Retrieval practice after multiple context changes, but not long retention intervals, reduces the impact of a final context change on instrumental behavior.

    Science.gov (United States)

    Trask, Sydney; Bouton, Mark E

    2018-06-01

    Recent evidence from this laboratory suggests that a context switch after operant learning consistently results in a decrement in responding. One way to reduce this decrement is to train the response in multiple contexts. One interpretation of this result, rooted in stimulus sampling theory, is that conditioning of a greater number of common stimulus elements arising from more contexts causes better generalization to new contexts. An alternative explanation is that each change of context causes more effortful retrieval, and practice involving effortful retrieval results in learning that is better able to transfer to new situations. The current experiments were designed to differentiate between these two explanations for the first time in an animal learning and memory task. Experiment 1 demonstrated that the detrimental impact of a context change on an instrumental nose-poking response can be reduced by training the response in multiple contexts. Experiment 2 then found that a training procedure which inserted extended retention intervals between successive training sessions did not reduce the detrimental impact of a final context change. This occurred even though the inserted retention intervals had a detrimental impact on responding (and, thus, presumably retrieval) similar to the effect that context switches had in Experiment 1. Together, the results suggest that effortful retrieval practice may not be sufficient to reduce the negative impact of a context change on instrumental behavior. A common elements explanation which supposes that physical and temporal contextual cues do not overlap may account for the findings more readily.

  1. Impact of a new condensed toluene mechanism on air quality model predictions in the US

    Directory of Open Access Journals (Sweden)

    G. Sarwar

    2011-03-01

    Full Text Available A new condensed toluene mechanism is incorporated into the Community Multiscale Air Quality Modeling system. Model simulations are performed using the CB05 chemical mechanism containing the existing (base and the new toluene mechanism for the western and eastern US for a summer month. With current estimates of tropospheric emission burden, the new toluene mechanism increases monthly mean daily maximum 8-h ozone by 1.0–3.0 ppbv in Los Angeles, Portland, Seattle, Chicago, Cleveland, northeastern US, and Detroit compared to that with the base toluene chemistry. It reduces model mean bias for ozone at elevated observed ozone concentrations. While the new mechanism increases predicted ozone, it does not enhance ozone production efficiency. A sensitivity study suggests that it can further enhance ozone if elevated toluene emissions are present. While it increases in-cloud secondary organic aerosol substantially, its impact on total fine particle mass concentration is small.

  2. EFFORTS TO IMPROVE THE ABILITY TO USE MEASURING INSTRUMENT STUDENT LEARNING THROUGH MEDIA MACROMEDIA FLASH IN CLASS X MECHANICAL MACHINING SMK 1 SEDAYU ACADEMIC YEAR 2012/2013

    Directory of Open Access Journals (Sweden)

    Puput Hananto

    2013-12-01

    Full Text Available This study aimed to describe the effect of instructional media makromedia flash in improving the students practical skill on subjects Measure Measuring Precision Mechanics class X Mechanical Engineering SMK 1 Sedayu Academic Year 2012/2013. This study included in Classroom Action Research (CAR. This study was conducted in two cycles, in 1 cycle has 3 times with the research subjects are class X students of SMK 1 Sedayu TPm totaling 32 students. The data were obtained from observations during learning activities by using observation sheets, tests, documents and photographs. Results obtained were analyzed with descriptive statistical analysis. The results showed that the ability of the students to practice using instructional media on subjects macromedia flash Measuring with Precision Mechanical Measuring Instrument has increased as follows: the initial capabilities obtained an average value of 65.9 after treatment in the first cycle the average value becomes 76.1. While the values obtained in the second cycle to 84.8 average. Based on the study results, the authors suggest that teachers improve the application of instructional media in learning macromedia flash so the ability to practice and student achievement will increase.

  3. Rebound mechanics of micrometre-scale, spherical particles in high-velocity impacts.

    Science.gov (United States)

    Yildirim, Baran; Yang, Hankang; Gouldstone, Andrew; Müftü, Sinan

    2017-08-01

    The impact mechanics of micrometre-scale metal particles with flat metal surfaces is investigated for high-velocity impacts ranging from 50 m s -1 to more than 1 km s -1 , where impact causes predominantly plastic deformation. A material model that includes high strain rate and temperature effects on the yield stress, heat generation due to plasticity, material damage due to excessive plastic strain and heat transfer is used in the numerical analysis. The coefficient of restitution e is predicted by the classical work using elastic-plastic deformation analysis with quasi-static impact mechanics to be proportional to [Formula: see text] and [Formula: see text] for the low and moderate impact velocities that span the ranges of 0-10 and 10-100 m s -1 , respectively. In the elastic-plastic and fully plastic deformation regimes the particle rebound is attributed to the elastic spring-back that initiates at the particle-substrate interface. At higher impact velocities (0.1-1 km s -1 ) e is shown to be proportional to approximately [Formula: see text]. In this deeply plastic deformation regime various deformation modes that depend on plastic flow of the material including the time lag between the rebound instances of the top and bottom points of particle and the lateral spreading of the particle are identified. In this deformation regime, the elastic spring-back initiates subsurface, in the substrate.

  4. Development of an instrument to assess the impact of an enhanced experiential model on pharmacy students' learning opportunities, skills and attitudes: A retrospective comparative-experimentalist study

    Directory of Open Access Journals (Sweden)

    Collins John B

    2008-04-01

    Full Text Available Abstract Background Pharmacy schools across North America have been charged to ensure their students are adequately skilled in the principles and practices of pharmaceutical care. Despite this mandate, a large percentage of students experience insufficient opportunities to practice the activities, tasks and processes essential to pharmaceutical care. The objective of this retrospective study of pharmacy students was to: (1 as "proof of concept", test the overall educational impact of an enhanced advanced pharmacy practice experiential (APPE model on student competencies; (2 develop an instrument to measure students' and preceptors' experiences; and (3 assess the psychometric properties of the instrument. Methods A comparative-experimental design, using student and preceptor surveys, was used to evaluate the impact of the enhanced community-based APPE over the traditional APPE model. The study was grounded in a 5-stage learning model: (1 an enhanced learning climate leads to (2 better utilization of learning opportunities, including (3 more frequent student/patient consultation, then to (4 improved skills acquisition, thence to (5 more favorable attitudes toward pharmaceutical care practice. The intervention included a one-day preceptor workshop, a comprehensive on-site student orientation and extending the experience from two four-week experiences in different pharmacies to one eight-week in one pharmacy. Results The 35 student and 38 preceptor survey results favored the enhanced model; with students conducting many more patient consultations and reporting greater skills improvement. In addition, the student self-assessment suggested changes in attitudes favoring pharmaceutical care principles. Psychometric testing showed the instrument to be sensitive, valid and reliable in ascertaining differences between the enhanced and traditional arms. Conclusion The enhanced experiential model positively affects learning opportunities and competency

  5. Impact of Different Ventilation Strategies on Driving Pressure, Mechanical Power, and Biological Markers During Open Abdominal Surgery in Rats

    NARCIS (Netherlands)

    Maia, Lígia de A.; Samary, Cynthia S.; Oliveira, Milena V.; Santos, Cintia L.; Huhle, Robert; Capelozzi, Vera L.; Morales, Marcelo M.; Schultz, Marcus J.; Abreu, Marcelo G.; Pelosi, Paolo; Silva, Pedro L.; Rocco, Patricia Rieken Macedo

    2017-01-01

    Intraoperative mechanical ventilation may yield lung injury. To date, there is no consensus regarding the best ventilator strategy for abdominal surgery. We aimed to investigate the impact of the mechanical ventilation strategies used in 2 recent trials (Intraoperative Protective Ventilation

  6. Instrumental interaction

    OpenAIRE

    Luciani , Annie

    2007-01-01

    International audience; The expression instrumental interaction as been introduced by Claude Cadoz to identify a human-object interaction during which a human manipulates a physical object - an instrument - in order to perform a manual task. Classical examples of instrumental interaction are all the professional manual tasks: playing violin, cutting fabrics by hand, moulding a paste, etc.... Instrumental interaction differs from other types of interaction (called symbolic or iconic interactio...

  7. Mechanical Characterization of the Human Lumbar Intervertebral Disc Subjected to Impact Loading Conditions

    Science.gov (United States)

    Jamison, David, IV

    Low back pain is a large and costly problem in the United States. Several working populations, such as miners, construction workers, forklift operators, and military personnel, have an increased risk and prevalence of low back pain compared to the general population. This is due to exposure to repeated, transient impact shocks, particularly while operating vehicles or other machinery. These shocks typically do not cause acute injury, but rather lead to pain and injury over time. The major focus in low back pain is often the intervertebral disc, due to its role as the major primary load-bearing component along the spinal column. The formation of a reliable standard for human lumbar disc exposure to repeated transient shock could potentially reduce injury risk for these working populations. The objective of this project, therefore, is to characterize the mechanical response of the lumbar intervertebral disc subjected to sub-traumatic impact loading conditions using both cadaveric and computational models, and to investigate the possible implications of this type of loading environment for low back pain. Axial, compressive impact loading events on Naval high speed boats were simulated in the laboratory and applied to human cadaveric specimen. Disc stiffness was higher and hysteresis was lower than quasi-static loading conditions. This indicates a shift in mechanical response when the disc is under impact loads and this behavior could be contributing to long-term back pain. Interstitial fluid loss and disc height changes were shown to affect disc impact mechanics in a creep study. Neutral zone increased, while energy dissipation and low-strain region stiffness decreased. This suggests that the disc has greater clinical instability during impact loading with progressive creep and fluid loss, indicating that time of day should be considered for working populations subjected to impact loads. A finite element model was developed and validated against cadaver specimen

  8. Cogongrass (Imperata cylindrica invasions in the US: Mechanisms, impacts, and threats to biodiversity

    Directory of Open Access Journals (Sweden)

    James A. Estrada

    2015-01-01

    Full Text Available Invasions of non-native species can suppress biodiversity and alter ecosystem functions, but for many of the most widespread invasive species the mechanisms underlying their invasive success and effects on native species are poorly understood. Here we evaluated the peer-reviewed literature on causes and impacts of invasion by cogongrass (Imperata cylindrica, one of the most problematic invasive plant species in the southeast US. We assess what is known about why cogongrass is particularly invasive and how it affects native communities and ecosystems, review patterns in research methods employed, and provide a roadmap for future research on cogongrass. Although many studies have focused on the basic biology and management of cogongrass, we found surprisingly few (30 studies that have directly tested mechanisms or impacts of cogongrass invasions. The most commonly tested mechanisms, disturbance and allelopathy, were evaluated 4 and 12 times, respectively, and studies on invasion impacts were limited to five studies total: native plant diversity (2 studies, nitrogen cycling (2, decomposition (1, and fine fuel loads (1. Excluding laboratory studies on allelopathy, 75% (6/8 of impact studies used observational methods, raising questions about cause and effect. Given the paucity of studies on the ecology of cogongrass invasions, and the need to protect conservation areas from invasions, we urge that research efforts focus on: (1 environmental correlates of distribution and performance, (2 the role of propagule pressure in invasion success, (3 enemy release and post-introduction evolution as mechanisms of invasion, and (4 experimental tests of community and ecosystem impacts of invasions.

  9. Impact of mechanical stretch on the cell behaviors of bone and surrounding tissues

    Directory of Open Access Journals (Sweden)

    Hye-Sun Yu

    2016-02-01

    Full Text Available Mechanical loading is recognized to play an important role in regulating the behaviors of cells in bone and surrounding tissues in vivo. Many in vitro studies have been conducted to determine the effects of mechanical loading on individual cell types of the tissues. In this review, we focus specifically on the use of the Flexercell system as a tool for studying cellular responses to mechanical stretch. We assess the literature describing the impact of mechanical stretch on different cell types from bone, muscle, tendon, ligament, and cartilage, describing individual cell phenotype responses. In addition, we review evidence regarding the mechanotransduction pathways that are activated to potentiate these phenotype responses in different cell populations.

  10. Impact of mechanical stretch on the cell behaviors of bone and surrounding tissues

    Science.gov (United States)

    Yu, Hye-Sun; Kim, Jung-Ju; Kim, Hae-Won; Lewis, Mark P; Wall, Ivan

    2016-01-01

    Mechanical loading is recognized to play an important role in regulating the behaviors of cells in bone and surrounding tissues in vivo. Many in vitro studies have been conducted to determine the effects of mechanical loading on individual cell types of the tissues. In this review, we focus specifically on the use of the Flexercell system as a tool for studying cellular responses to mechanical stretch. We assess the literature describing the impact of mechanical stretch on different cell types from bone, muscle, tendon, ligament, and cartilage, describing individual cell phenotype responses. In addition, we review evidence regarding the mechanotransduction pathways that are activated to potentiate these phenotype responses in different cell populations. PMID:26977284

  11. Selection mechanisms underlying high impact biomedical research--a qualitative analysis and causal model.

    Directory of Open Access Journals (Sweden)

    Hilary Zelko

    Full Text Available BACKGROUND: Although scientific innovation has been a long-standing topic of interest for historians, philosophers and cognitive scientists, few studies in biomedical research have examined from researchers' perspectives how high impact publications are developed and why they are consistently produced by a small group of researchers. Our objective was therefore to interview a group of researchers with a track record of high impact publications to explore what mechanism they believe contribute to the generation of high impact publications. METHODOLOGY/PRINCIPAL FINDINGS: Researchers were located in universities all over the globe and interviews were conducted by phone. All interviews were transcribed using standard qualitative methods. A Grounded Theory approach was used to code each transcript, later aggregating concept and categories into overarching explanation model. The model was then translated into a System Dynamics mathematical model to represent its structure and behavior. Five emerging themes were found in our study. First, researchers used heuristics or rules of thumb that came naturally to them. Second, these heuristics were reinforced by positive feedback from their peers and mentors. Third, good communication skills allowed researchers to provide feedback to their peers, thus closing a positive feedback loop. Fourth, researchers exhibited a number of psychological attributes such as curiosity or open-mindedness that constantly motivated them, even when faced with discouraging situations. Fifth, the system is dominated by randomness and serendipity and is far from a linear and predictable environment. Some researchers, however, took advantage of this randomness by incorporating mechanisms that would allow them to benefit from random findings. The aggregation of these themes into a policy model represented the overall expected behavior of publications and their impact achieved by high impact researchers. CONCLUSIONS: The proposed

  12. Mechanical resistance of UO{sub 2} pellet by means of free-fall-impact testing

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Tae-sik; Lee, Seung-jae; Kim, Jae-ik; Jo, Young-ho; Park, Bo-yong; Ko, Sang-ern [KEPCO NF, Daejeon (Korea, Republic of)

    2014-10-15

    A fuel rod failed during a power transient can be seen in Fig 1. and conjunction of a chipped pellet with a cladding crack has been observed in commercial reactors through the post-irradiation examinations. It revealed that missing-pellet-surface(MPS) was one of the reasons of the fuel failure. The mechanism of this failure mode that MPS induces the asymmetry of the pellet-cladding mechanical system mainly comprises a stress concentration at the inner surface resulting in non-classical PCI. The fracture toughness is largely close to material property. It is assumed that by optimizing surface design of UO{sub 2} pellet, the strength arises because theoretical strength is considerably affected by geometry as one of a parameter of factor 'f'. Pellet research for design optimization to achieve better resistance to external load should be accompanied with volumetric approach to the improvement of mechanical behavior of pellet being still ongoing. At this work, the resistance to external load is analyzed varying with the geometry of pellets and angles of impact on UO{sub 2} pellet surface by the free-fall-impact test method. The tested specimens were equivalently produced and sintered for having the same volumetric property such as sinter density and grain size expect the surface with different geometry design at the end face and shoulder which includes dish, chamfer and land in dimension and angle. Missing-pellet-surface(MPS) on UO{sub 2} pellet is inevitable behavior during manufacturing, handling and burning in reactor and brings about non-classical PCI behavior that could damage fuel rod integrity. For this reason, the free-fall-drop tester was developed by KEPCO NF Material Development laboratory in Daejeon for quantitatively investigating the mechanical behavior of UO{sub 2}. The free-fall-impact test is performed by dropping hammer on pellet shoulder with certain impact energy and at various angles. The result is quantitatively measured with weighing

  13. Relationship of mechanical impact magnitude to neurologic dysfunction severity in a rat traumatic brain injury model.

    Directory of Open Access Journals (Sweden)

    Tsung-Hsun Hsieh

    Full Text Available Traumatic brain injury (TBI is a major brain injury type commonly caused by traffic accidents, falls, violence, or sports injuries. To obtain mechanistic insights about TBI, experimental animal models such as weight-drop-induced TBI in rats have been developed to mimic closed-head injury in humans. However, the relationship between the mechanical impact level and neurological severity following weight-drop-induced TBI remains uncertain. In this study, we comprehensively investigated the relationship between physical impact and graded severity at various weight-drop heights.The acceleration, impact force, and displacement during the impact were accurately measured using an accelerometer, a pressure sensor, and a high-speed camera, respectively. In addition, the longitudinal changes in neurological deficits and balance function were investigated at 1, 4, and 7 days post TBI lesion. The inflammatory expression markers tested by Western blot analysis, including glial fibrillary acidic protein, beta-amyloid precursor protein, and bone marrow tyrosine kinase gene in chromosome X, in the frontal cortex, hippocampus, and corpus callosum were investigated at 1 and 7 days post-lesion.Gradations in impact pressure produced progressive degrees of injury severity in the neurological score and balance function. Western blot analysis demonstrated that all inflammatory expression markers were increased at 1 and 7 days post-impact injury when compared to the sham control rats. The severity of neurologic dysfunction and induction in inflammatory markers strongly correlated with the graded mechanical impact levels.We conclude that the weight-drop-induced TBI model can produce graded brain injury and induction of neurobehavioral deficits and may have translational relevance to developing therapeutic strategies for TBI.

  14. Impact of Injury Mechanisms on Patterns and Management of Facial Fractures.

    Science.gov (United States)

    Greathouse, S Travis; Adkinson, Joshua M; Garza, Ramon; Gilstrap, Jarom; Miller, Nathan F; Eid, Sherrine M; Murphy, Robert X

    2015-07-01

    Mechanisms causing facial fractures have evolved over time and may be predictive of the types of injuries sustained. The objective of this study is to examine the impact of mechanisms of injury on the type and management of facial fractures at our Level 1 Trauma Center. The authors performed an Institutional Review Board-approved review of our network's trauma registry from 2006 to 2010, documenting age, sex, mechanism, Injury Severity Score, Glasgow Coma Scale, facial fracture patterns (nasal, maxillary/malar, orbital, mandible), and reconstructions. Mechanism rates were compared using a Pearson χ2 test. The database identified 23,318 patients, including 1686 patients with facial fractures and a subset of 1505 patients sustaining 2094 fractures by motor vehicle collision (MVC), fall, or assault. Nasal fractures were the most common injuries sustained by all mechanisms. MVCs were most likely to cause nasal and malar/maxillary fractures (P management. Age and number of fractures sustained were associated with operative intervention. Although there is a statistically significant correlation between mechanism of injury and type of facial fracture sustained, none of the mechanisms evaluated herein are statistically associated with surgical intervention. Clinical Question/Level of Evidence: Therapeutic, III.

  15. Mechanical characteristics of plastic base Ports and impact on flushing efficacy.

    Science.gov (United States)

    Guiffant, Gérard; Flaud, Patrice; Royon, Laurent; Burnet, Espérie; Merckx, Jacques

    2017-01-01

    Three types of totally implantable venous access devices, Ports, are currently in use: titanium, plastic (polyoxymethylene, POM), and mixed (titanium base with a POM shell). Physics theory suggests that the interaction between a non-coring needle (NCN, made of stainless steel) and a plastic base would lead to the stronger material (steel) altering the more malleable material (plastic). To investigate whether needle impacts can alter a plastic base's surface, thus potentially reducing flushing efficacy. A Port made of POM was punctured 200 times with a 19-gauge NCN. Following the existing guidelines, the needle tip pricked the base with each puncture. The Port's base was then examined using a two-dimensional optical instrument, and a bi-dimensional numerical simulation using COMSOL ® was performed to investigate potential surface irregularities and their impact on fluid flow. Each needle impact created a hole (mean depth, 0.12 mm) with a small bump beside it (mean height, 0.02 mm) the Reynolds number Re k ≈10. A numerical simulation of the one hole/bump set showed that the flushing efficacy was 60% that of flushing along a flat surface. In clinical practice, the number of times a Port is punctured depends on patient and treatment characteristics, but each needle impact on the plastic base may increase the risk of decreased flushing effectiveness. Therefore, the more a plastic Port is accessed, the greater the risk of microorganisms, blood products, and medication accumulation. Multiple needle impacts created an irregular surface on the Port's base, which decreased flushing efficacy. Clinical investigation is needed to determine whether plastic base Ports are associated with an increased risk of Port infection and occlusion compared to titanium base Ports.

  16. The impact of the use of different types of gloves and bare hands for preparation of clean surgical instruments.

    Science.gov (United States)

    Bruna, Camila Quartim de Moraes; Souza, Rafael Queiroz de; Massaia, Irineu Francisco Silva; Cruz, Áurea Silveira; Graziano, Kazuko Uchikawa

    2016-10-10

    to determine if there are differences on the safety of the preparation of clean surgical instruments using different types of gloves and bare hands and evaluate the microbiological load of these preparations without gloves. laboratory procedure with a pragmatic approach, in which the samples were handled with different types of gloves and bare hands. In addition, cytotoxicity assays were carried out by means of the agar diffusion method. Further samples were subjected to microbiological analysis after being handled without gloves. none of the samples showed cytotoxic effect. All microbiological cultures showed growth of microorganisms, but no microorganism has been recovered after autoclaving. there were no differences in the cytotoxic responses regarding the use of different types of gloves and bare hands in the handling of clean surgical instruments, which could entail iatrogenic risk. It is noteworthy that the use of gloves involves increase in the costs of process and waste generation, and the potential allergenic risk to latex. determinar se existe diferenças na segurança do preparo de instrumentais cirúrgicos relacionada ao uso de distintos tipos de luvas e das mãos nuas no preparo, e avaliar a carga microbiológica destes preparados sem luvas. experimento laboratorial com abordagem pragmática, onde amostras foram manipuladas com diferentes tipos de luvas e com as mãos nuas, elaborado teste de citotoxicidade por meio da difusão em ágar. Outras Amostras sofreram análise microbiológica após serem manipuladas sem luvas. nenhuma das amostras apresentou efeito citotóxico. Todas as culturas microbiológicas apresentaram crescimento de microrganismos, embora nenhum microrganismo tenha sido recuperado após a autoclavação. não houve diferenças nas respostas citotóxicas relacionadas ao uso de diferentes tipos de luvas e das mãos nuas na manipulação do instrumental cirúrgico limpo que sinalizasse risco de iatrogenia. Ressalta-se que o uso de luvas

  17. The Impact of Halloysite on the Thermo-Mechanical Properties of Polymer Composites.

    Science.gov (United States)

    Gaaz, Tayser Sumer; Sulong, Abu Bakar; Kadhum, Abdul Amir H; Al-Amiery, Ahmed A; Nassir, Mohamed H; Jaaz, Ahed Hameed

    2017-05-20

    Nanotubular clay minerals, composed of aluminosilicate naturally structured in layers known as halloysite nanotubes (HNTs), have a significant reinforcing impact on polymer matrixes. HNTs have broad applications in biomedical applications, the medicine sector, implant alloys with corrosion protection and manipulated transportation of medicines. In polymer engineering, different research studies utilize HNTs that exhibit a beneficial enhancement in the properties of polymer-based nanocomposites. The dispersion of HNTs is improved as a result of pre-treating HNTs with acids. The HNTs' percentage additive up to 7% shows the highest improvement of tensile strength. The degradation of the polymer can be also significantly improved by doping a low percentage of HNTs. Both the mechanical and thermal properties of polymers were remarkably improved when mixed with HNTs. The effects of HNTs on the mechanical and thermal properties of polymers, such as ultimate strength, elastic modulus, impact strength and thermal stability, are emphasized in this study.

  18. Impact of mechanical stress induced in silica vacuum windows on laser-induced damage.

    Science.gov (United States)

    Gingreau, Clémence; Lanternier, Thomas; Lamaignère, Laurent; Donval, Thierry; Courchinoux, Roger; Leymarie, Christophe; Néauport, Jérôme

    2018-04-15

    At the interface between vacuum and air, optical windows must keep their optical properties, despite being subjected to mechanical stress. In this Letter, we investigate the impact of such stress on the laser-induced damage of fused silica windows at the wavelength of 351 nm in the nanosecond regime. Different stress values, from 1 to 30 MPa, both tensile and compressive, were applied. No effect of the stress on the laser-induced damage was evidenced.

  19. Impact of Interlayer Dwell Time on Microstructure and Mechanical Properties of Nickel and Titanium Alloys

    Science.gov (United States)

    Foster, B. K.; Beese, A. M.; Keist, J. S.; McHale, E. T.; Palmer, T. A.

    2017-09-01

    Path planning in additive manufacturing (AM) processes has an impact on the thermal histories experienced at discrete locations in simple and complex AM structures. One component of path planning in directed energy deposition is the time required for the laser or heat source to return to a given location to add another layer of material. As structures become larger and more complex, the length of this interlayer dwell time can significantly impact the resulting thermal histories. The impact of varying dwell times between 0 and 40 seconds on the microstructural and mechanical properties of Inconel® 625 and Ti-6Al-4V builds has been characterized. Even though these materials display different microstructures and solid-state phase transformations, the addition of an interlayer dwell generally led to a finer microstructure in both materials that impacted the resulting mechanical properties. With the addition of interlayer dwell times up to 40 seconds in the Inconel® 625 builds, finer secondary dendrite arm spacing values, produced by changes in the thermal history, correspond to increased yield and tensile strengths. These mechanical properties did not appear to change significantly, however, for dwell times greater than 20 seconds in the Inconel® 625 builds, indicating that longer dwell times have a minimal impact. The addition of interlayer dwell times in Ti-6Al-4V builds resulted in a slight decrease in the measured alpha lath widths and a much more noticeable decrease in the width of prior beta grains. In addition, the yield and tensile values continued to increase, nearly reaching the values observed in the rolled plate substrate material with dwell times up to 40 seconds.

  20. Permanent Magnet Brushless DC Motor and Mechanical Structure Design for the Electric Impact Wrench System

    Directory of Open Access Journals (Sweden)

    Chengyuan He

    2018-05-01

    Full Text Available This paper presents an analytical method to design an interior permanent magnet brushless DC electric motor (IPMBLDC motor for a kind of electric impact wrench used for loading and unloading car bolts. It takes into account magnet assembly gap, rotor saturation webs, and bridges. Assumed flux leakage coefficient and selected working point of a permanent magnet were used in the initial design. An advanced equivalent magnetic circuit was developed to verify the total flux leakage and the quiescent operating point based on initial design parameters. Key design method points are considered and analyzed. Thermal analysis is given to simulate the temperature rise of all parts of the motor. The new impact wrench mechanical structure is designed, and its working principle analyzed. An electromagnetic field analysis based on MATLAB and the MAXWELL 2D finite element method (FEM were used in the design to verify the equivalent magnetic circuit and optimize the IPMBLDC motor parameters. Experimental results are obtained to verify the design. The electrical and mechanical designs are combined and an analytical IPMBLDC motor design method is provided. We also show an innovative and reasonable mechanical dynamical calculation method for the impact wrench system, which can be used in whole system design of other functional electric tools.

  1. The Role of Malware in Reported Cyber Espionage: A Review of the Impact and Mechanism

    Directory of Open Access Journals (Sweden)

    Gaute Wangen

    2015-05-01

    Full Text Available The recent emergence of the targeted use of malware in cyber espionage versus industry requires a systematic review for better understanding of its impact and mechanism. This paper proposes a basic taxonomy to document major cyber espionage incidents, describing and comparing their impacts (geographic or political targets, origins and motivations and their mechanisms (dropper, propagation, types of operating systems and infection rates. This taxonomy provides information on recent cyber espionage attacks that can aid in defense against cyber espionage by providing both scholars and experts a solid foundation of knowledge about the topic. The classification also provides a systematic way to document known and future attacks to facilitate research activities. Geopolitical and international relations researchers can focus on the impacts, and malware and security experts can focus on the mechanisms. We identify several dominant patterns (e.g., the prevalent use of remote access Trojan and social engineering. This article concludes that the research and professional community should collaborate to build an open data set to facilitate the geopolitical and/or technical analysis and synthesis of the role of malware in cyber espionage.

  2. Poor cognitive ageing: Vulnerabilities, mechanisms and the impact of nutritional interventions.

    Science.gov (United States)

    Miquel, Sophie; Champ, Claire; Day, Jon; Aarts, Esther; Bahr, Ben A; Bakker, Martijntje; Bánáti, Diána; Calabrese, Vittorio; Cederholm, Tommy; Cryan, John; Dye, Louise; Farrimond, Jonathan A; Korosi, Aniko; Layé, Sophie; Maudsley, Stuart; Milenkovic, Dragan; Mohajeri, M Hasan; Sijben, John; Solomon, Alina; Spencer, Jeremy P E; Thuret, Sandrine; Vanden Berghe, Wim; Vauzour, David; Vellas, Bruno; Wesnes, Keith; Willatts, Peter; Wittenberg, Raphael; Geurts, Lucie

    2018-03-01

    Ageing is a highly complex process marked by a temporal cascade of events, which promote alterations in the normal functioning of an individual organism. The triggers of normal brain ageing are not well understood, even less so the factors which initiate and steer the neuronal degeneration, which underpin disorders such as dementia. A wealth of data on how nutrients and diets may support cognitive function and preserve brain health are available, yet the molecular mechanisms underlying their biological action in both normal ageing, age-related cognitive decline, and in the development of neurodegenerative disorders have not been clearly elucidated. This review aims to summarise the current state of knowledge of vulnerabilities that predispose towards dysfunctional brain ageing, highlight potential protective mechanisms, and discuss dietary interventions that may be used as therapies. A special focus of this paper is on the impact of nutrition on neuroprotection and the underlying molecular mechanisms, and this focus reflects the discussions held during the 2nd workshop 'Nutrition for the Ageing Brain: Functional Aspects and Mechanisms' in Copenhagen in June 2016. The present review is the most recent in a series produced by the Nutrition and Mental Performance Task Force under the auspice of the International Life Sciences Institute Europe (ILSI Europe). Coupling studies of cognitive ageing with studies investigating the effect of nutrition and dietary interventions as strategies targeting specific mechanisms, such as neurogenesis, protein clearance, inflammation, and non-coding and microRNAs is of high value. Future research on the impact of nutrition on cognitive ageing will need to adopt a longitudinal approach and multimodal nutritional interventions will likely need to be imposed in early-life to observe significant impact in older age. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Impact of Tracheostomy Placement on Anxiety in Mechanically Ventilated Adult ICU Patients

    Science.gov (United States)

    Breckenridge, Stephanie J.; Chlan, Linda; Savik, Kay

    2014-01-01

    OBJECTIVE To determine if self-reported anxiety levels decreased after tracheostomy placement in a sample of mechanically ventilated intensive care unit patients. BACKGROUND There is limited research regarding the impact of a tracheostomy on patients’ anxiety. Elevated anxiety delays healing and contributes to long-term mental health complications. METHODS This was a secondary analysis of data from a large clinical trial conducted in urban Minnesota. Fifty-one of 116 patients received a tracheostomy. Anxiety scores were obtained daily using the Visual Analog Scale-Anxiety. Mixed model analysis was used to compare anxiety ratings pre- and post-tracheostomy. RESULTS There was no significant decrease in anxiety following tracheostomy after controlling for time and gender (all p>.16). Age was the only variable to impact anxiety levels: anxiety scores increased as age increased (p=.02). CONCLUSIONS Prospective studies are needed to more accurately assess the impact of tracheostomy placement on patient anxiety and salient outcomes. PMID:24559754

  4. Mechanical performance of carbon-epoxy laminates. Part I: quasi-static and impact bending properties

    Directory of Open Access Journals (Sweden)

    José Ricardo Tarpani

    2006-06-01

    Full Text Available In Part I of this study, quasi-static and impact bending properties of four aeronautical grade carbon-epoxy laminates have been determined and compared. Materials tested were unidirectional cross-ply (tape and bidirectional woven textile (fabric carbon fiber lay-up architectures, impregnated with standard and rubber-toughened resins, respectively, giving rise to 1.5 mm-thick laminates. Quasi-static mechanical properties assessed in transversal mode loading were modulus of elasticity, flexural strength and tenacity at the maximum load, whereas the net absorbed energy was determined under translaminar impact conditions. Two-dimensional woven carbon fiber reinforcements embedded in a rubber-toughened matrix presented the best mechanical performance under static loading. Under dynamic loading conditions, woven fiber fabric pre-forms were favorably sensitive to increasing impact energies regardless the nature of the employed epoxy resin. However, it was concluded that great care should be taken with this material within the low energy impact regimen.

  5. Instrument performance evaluation

    International Nuclear Information System (INIS)

    Swinth, K.L.

    1993-03-01

    Deficiencies exist in both the performance and the quality of health physics instruments. Recognizing the implications of such deficiencies for the protection of workers and the public, in the early 1980s the DOE and the NRC encouraged the development of a performance standard and established a program to test a series of instruments against criteria in the standard. The purpose of the testing was to establish the practicality of the criteria in the standard, to determine the performance of a cross section of available instruments, and to establish a testing capability. Over 100 instruments were tested, resulting in a practical standard and an understanding of the deficiencies in available instruments. In parallel with the instrument testing, a value-impact study clearly established the benefits of implementing a formal testing program. An ad hoc committee also met several times to establish recommendations for the voluntary implementation of a testing program based on the studies and the performance standard. For several reasons, a formal program did not materialize. Ongoing tests and studies have supported the development of specific instruments and have helped specific clients understand the performance of their instruments. The purpose of this presentation is to trace the history of instrument testing to date and suggest the benefits of a centralized formal program

  6. Modeling the impact of scaffold architecture and mechanical loading on collagen turnover in engineered cardiovascular tissues.

    Science.gov (United States)

    Argento, G; de Jonge, N; Söntjens, S H M; Oomens, C W J; Bouten, C V C; Baaijens, F P T

    2015-06-01

    The anisotropic collagen architecture of an engineered cardiovascular tissue has a major impact on its in vivo mechanical performance. This evolving collagen architecture is determined by initial scaffold microstructure and mechanical loading. Here, we developed and validated a theoretical and computational microscale model to quantitatively understand the interplay between scaffold architecture and mechanical loading on collagen synthesis and degradation. Using input from experimental studies, we hypothesize that both the microstructure of the scaffold and the loading conditions influence collagen turnover. The evaluation of the mechanical and topological properties of in vitro engineered constructs reveals that the formation of extracellular matrix layers on top of the scaffold surface influences the mechanical anisotropy on the construct. Results show that the microscale model can successfully capture the collagen arrangement between the fibers of an electrospun scaffold under static and cyclic loading conditions. Contact guidance by the scaffold, and not applied load, dominates the collagen architecture. Therefore, when the collagen grows inside the pores of the scaffold, pronounced scaffold anisotropy guarantees the development of a construct that mimics the mechanical anisotropy of the native cardiovascular tissue.

  7. Impact of two chemistry mechanisms fully coupled with mesoscale model on the atmospheric pollutants distribution

    Science.gov (United States)

    Arteta, J.; Cautenet, S.; Taghavi, M.; Audiffren, N.

    Air quality models (AQM) consist of many modules (meteorology, emission, chemistry, deposition), and in some conditions such as: vicinity of clouds or aerosols plumes, complex local circulations (mountains, sea breezes), fully coupled models (online method) are necessary. In order to study the impact of lumped chemical mechanisms in AQM simulations, we examine the ability of both different chemical mechanisms: (i) simplified: Condensed Version of the MOdèle de Chimie Atmosphérique 2.2 (CV-MOCA2.2), and (ii) reference: Regional Atmospheric Chemistry Model (RACM), which are coupled online with the Regional Atmospheric Modeling Systems (RAMS) model, on the distribution of pollutants. During the ESCOMPTE experiment (Expérience sur Site pour COntraindre les Modèles de Pollution et de Transport d'Emissions) conducted over Southern France (including urban and industrial zones), Intensive observation periods (IOP) characterized by various meteorological and mixed chemical conditions are simulated. For both configurations of modeling, numerical results are compared with surface measurements (75 stations) for primary (NO x) and secondary (O 3) species. We point out the impact of the two different chemical mechanisms on the production of species involved in the oxidizing capacity such as ozone and radicals within urban and industrial areas. We highlight that both chemical mechanisms produce very similar results for the main pollutants (NO x and O 3) in three-dimensional (3D) distribution, despite large discrepancies in 0D modeling. For ozone concentration, we found sometimes small differences (5-10 ppb) between the mechanisms under study according to the cases (polluted or not). The relative difference between the two mechanisms over the whole domain is only -7% for ozone from CV-MOCA 2.2 versus RACM. When the order of magnitude is needed rather than an accurate estimate, a reduced mechanism is satisfactory. It has the advantage of running faster (four times less than CPU

  8. Similar head impact acceleration measured using instrumented ear patches in a junior rugby union team during matches in comparison with other sports.

    Science.gov (United States)

    King, Doug A; Hume, Patria A; Gissane, Conor; Clark, Trevor N

    2016-07-01

    OBJECTIVE Direct impact with the head and the inertial loading of the head have been postulated as major mechanisms of head-related injuries, such as concussion. METHODS This descriptive observational study was conducted to quantify the head impact acceleration characteristics in under-9-year-old junior rugby union players in New Zealand. The impact magnitude, frequency, and location were collected with a wireless head impact sensor that was worn by 14 junior rugby players who participated in 4 matches. RESULTS A total of 721 impacts > 10g were recorded. The median (interquartile range [IQR]) number of impacts per player was 46 (IQR 37-58), resulting in 10 (IQR 4-18) impacts to the head per player per match. The median impact magnitudes recorded were 15g (IQR 12g-21g) for linear acceleration and 2296 rad/sec(2) (IQR 1352-4152 rad/sec(2)) for rotational acceleration. CONCLUSIONS There were 121 impacts (16.8%) above the rotational injury risk limit and 1 (0.1%) impact above the linear injury risk limit. The acceleration magnitude and number of head impacts in junior rugby union players were higher than those previously reported in similar age-group sports participants. The median linear acceleration for the under-9-year-old rugby players were similar to 7- to 8-year-old American football players, but lower than 9- to 12-year-old youth American football players. The median rotational accelerations measured were higher than the median and 95th percentiles in youth, high school, and collegiate American football players.

  9. Development and validation of an instrument to measure the impact of genetic testing on self-concept in Lynch syndrome

    DEFF Research Database (Denmark)

    Esplen, M J; Stuckless, N; Gallinger, S

    2011-01-01

    with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale showed excellent reliability (Cronbach's α = 0.93), good convergent validity by a high correlation with impact of event scale (r(102) = 0.55, p Rosenberg self-esteem scale...

  10. Instrumentation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Provides instrumentation support for flight tests of prototype weapons systems using a vast array of airborne sensors, transducers, signal conditioning and encoding...

  11. Mechanisms of impact of greenhouse gases on the Earth's ozone layer in the Polar Regions

    Science.gov (United States)

    Zadorozhny, Alexander; Dyominov, Igor

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the atmosphere including aerosol physics is used to examine the impact of the greenhouse gases CO2, CH4, and N2O on the future long-term changes of the Earth's ozone layer, in particular on its expected recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circu-lation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the North to South Poles, as well as distribution of sulphate aerosol particles and polar strato-spheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abun-dance of the greenhouse gases on the long-term changes of the Earth's ozone layer in the Polar Regions, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2, essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weak-ness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification be-gins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard

  12. An evaluation of instruments for scoring physiological and behavioral cues of pain, non-pain related distress, and adequacy of analgesia and sedation in pediatric mechanically ventilated patients: A systematic review.

    Science.gov (United States)

    Dorfman, Tamara L; Sumamo Schellenberg, Elizabeth; Rempel, Gwen R; Scott, Shannon D; Hartling, Lisa

    2014-04-01

    Advancing technology allows for successful treatment of children with life-threatening illnesses. Effectively assessing and optimally treating a child's distress during their stay in the Pediatric Intensive Care Unit (PICU) is paramount. Objective measures of distress in mechanically ventilated pediatric patients are increasingly available but few have been evaluated. The objectives of this systematic review were to identify available instruments appropriate for measuring physiological and behavioral cues of pain, non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated pediatric patients, and evaluate these instruments in terms of their psychometric properties. A systematic review of original and validation reports of objective instruments to measure pain and non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated PICU patients was undertaken. A comprehensive search was conducted in 10 databases from January 1970 to June 2011. Reference lists of relevant articles were reviewed to identify additional articles. Studies were included in the review if they met pre-established eligibility criteria. Two independent reviewers reviewed studies for inclusion, assessed quality, and extracted data. Twenty-five articles were included, identifying 15 instruments. The instruments had different foci including: assessing pain, non-pain related distress, and sedation (n=2); assessing pain exclusively (n=4); assessing sedation exclusively (n=7), assessing sedation in mechanically ventilated muscle relaxed PICU patients (n=1); and assessing delirium in mechanically ventilated PICU patients (n=1). The Comfort Scale demonstrated the greatest clinical utility in the assessment of pain, non-pain related distress, and sedation in mechanically ventilated pediatric patients. Modified FLACC and the MAPS are more appropriate, however, for the assessment of procedural pain and other brief painful events. More work is

  13. Use of simple finite elements for mechanical systems impact analysis based on stereomechanics, stress wave propagation, and energy method approaches

    International Nuclear Information System (INIS)

    McCoy, Michael L.; Moradi, Rasoul; Lankarani, Hamid M.

    2011-01-01

    This paper examines the effectiveness of analyzing impact events in mechanical systems for design purposes using simple or low ordered finite elements. Traditional impact dynamics analyses of mechanical systems namely stereomechanics, energy method, stress-wave propagation and contact mechanics approaches are limited to very simplified geometries and provide basic analyses in making predictions and understanding the dominant features of the impact in a mechanical system. In engineering practice, impacted systems present a complexity of geometry, stiffness, mass distributions, contact areas and impact angles that are impossible to analyze and design with the traditional impact dynamics methods. In real cases, the effective tool is the finite element (FE) method. The high-end FEA codes though may be not available for typical engineer/designer. This paper provides information on whether impact events of mechanical systems can be successfully modeled using simple or low-order finite elements. FEA models using simple elements are benchmarked against theoretical impact problems and published experimental impact results. As a case study, an FE model using simple plastic beam elements is further tested to predict stresses and deflections in an experimental structural impact

  14. Impact of the ozone monitoring instrument row anomaly on the long-term record of aerosol products

    Science.gov (United States)

    Torres, Omar; Bhartia, Pawan K.; Jethva, Hiren; Ahn, Changwoo

    2018-05-01

    Since about three years after the launch the Ozone Monitoring Instrument (OMI) on the EOS-Aura satellite, the sensor's viewing capability has been affected by what is believed to be an internal obstruction that has reduced OMI's spatial coverage. It currently affects about half of the instrument's 60 viewing positions. In this work we carry out an analysis to assess the effect of the reduced spatial coverage on the monthly average values of retrieved aerosol optical depth (AOD), single scattering albedo (SSA) and the UV Aerosol Index (UVAI) using the 2005-2007 three-year period prior to the onset of the row anomaly. Regional monthly average values calculated using viewing positions 1 through 30 were compared to similarly obtained values using positions 31 through 60, with the expectation of finding close agreement between the two calculations. As expected, mean monthly values of AOD and SSA obtained with these two scattering-angle dependent subsets of OMI observations agreed over regions where carbonaceous or sulphate aerosol particles are the predominant aerosol type. However, over arid regions, where desert dust is the main aerosol type, significant differences between the two sets of calculated regional mean values of AOD were observed. As it turned out, the difference in retrieved desert dust AOD between the scattering-angle dependent observation subsets was due to the incorrect representation of desert dust scattering phase function. A sensitivity analysis using radiative transfer calculations demonstrated that the source of the observed AOD bias was the spherical shape assumption of desert dust particles. A similar analysis in terms of UVAI yielded large differences in the monthly mean values for the two sets of calculations over cloudy regions. On the contrary, in arid regions with minimum cloud presence, the resulting UVAI monthly average values for the two sets of observations were in very close agreement. The discrepancy under cloudy conditions was found

  15. Causal mechanisms of soil organic matter decomposition: Deconstructing salinity and flooding impacts in coastal wetlands

    Science.gov (United States)

    Stagg, Camille L.; Schoolmaster, Donald; Krauss, Ken W.; Cormier, Nicole; Conner, William H.

    2017-01-01

    Coastal wetlands significantly contribute to global carbon storage potential. Sea-level rise and other climate change-induced disturbances threaten coastal wetland sustainability and carbon storage capacity. It is critical that we understand the mechanisms controlling wetland carbon loss so that we can predict and manage these resources in anticipation of climate change. However, our current understanding of the mechanisms that control soil organic matter decomposition, in particular the impacts of elevated salinity, are limited, and literature reports are contradictory. In an attempt to improve our understanding of these complex processes, we measured root and rhizome decomposition and developed a causal model to identify and quantify the mechanisms that influence soil organic matter decomposition in coastal wetlands that are impacted by sea-level rise. We identified three causal pathways: 1) a direct pathway representing the effects of flooding on soil moisture, 2) a direct pathway representing the effects of salinity on decomposer microbial communities and soil biogeochemistry, and 3) an indirect pathway representing the effects of salinity on litter quality through changes in plant community composition over time. We used this model to test the effects of alternate scenarios on the response of tidal freshwater forested wetlands and oligohaline marshes to short- and long-term climate-induced disturbances of flooding and salinity. In tidal freshwater forested wetlands, the model predicted less decomposition in response to drought, hurricane salinity pulsing, and long-term sea-level rise. In contrast, in the oligohaline marsh, the model predicted no change in response to sea-level rise, and increased decomposition following a drought or a hurricane salinity pulse. Our results show that it is critical to consider the temporal scale of disturbance and the magnitude of exposure when assessing the effects of salinity intrusion on carbon mineralization in coastal

  16. Hastes instrumentadas para a mensuração da resistência mecânica do solo Instrumented shanks for soil mechanical resistance measurements

    Directory of Open Access Journals (Sweden)

    Viacheslav I. Adamchuk

    2006-04-01

    Full Text Available A presença de camada de solo compactada pode significar sérios problemas ao desenvolvimento do sistema radicular das culturas em geral. A correção pode ser feita por métodos biológicos ou mecânicos. Uma das formas de diagnóstico da sua presença é com o uso de penetrômetros que exigem tempo considerável para a obtenção de dados. Com o advento dos recursos de espacialização das informações na forma de mapas, a necessidade de amostragem passou a ser ainda maior. Este trabalho reporta a busca de uma solução alternativa ao uso do penetrômetro. Envolve a geração de mapas de resistência mecânica do solo ao deslocamento de uma haste em três profundidades, baseado em três hastes instrumentadas, um receptor de GPS e um sistema de aquisição de dados. O sistema é acoplado a uma barra porta-ferramenta montada no engate de três pontos do trator. A configuração mostrou ser mecanicamente bastante simples e confiável. Dados de um teste inicial em campo demonstraram que o sistema pode produzir mapas que denotam a variabilidade espacial da referida resistência nas áreas amostradas, com alta resolução, densidade de amostragem elevada e com capacidade operacional ainda mais elevada se comparada com levantamentos feitos com métodos convencionais.The presence of soil compaction may be considered a serious problem for the development of crop root systems. It can be alleviated by biological or mechanical methods (such as tillage. One of the most popular diagnostic methods is based on standardized cone penetrometer measurements, which requires a considerable amount of time to obtain the data. With the advent of site-specific field management, high-density measurements have become a necessity. This work reports on an alternative approach to use a cone penetromenter. It involves the generation of maps of soil mechanical resistance at three depths using three instrumented blades, a GPS receiver and a data logger. The system is attached

  17. Study on the transplant impact on the elementary composition of Protousnea magellanica thallus by using instrumental neutron activation analysis; Estudio del impacto del transplante en la composicion elemental de Protousnea magellanica utilizando analisis por activacion neutronica instrumental

    Energy Technology Data Exchange (ETDEWEB)

    Bubach, Debora; Guevara, Sergio Ribeiro; Arribere, Maria A.; Wiesztort, Andres [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche. Lab. de Analisis por Activacion Nautronica; Calvelo, Susana [Universidad Nacional del Comahue, Bariloche (Argentina). Centro Regional Universitario Bariloche

    1999-11-01

    As part of a study on the use of the furticose lichen Protousnea magellanica as a bio indicator of atmospheric pollution, it was studied the impact on the elemental composition of the thallus when this lichen is transplanted in the same area under similar environmental conditions. The lichens were collected and replanted in a pristine area in Puerto Blest, Nahuel Huapi National Park, Bariloche, Argentina. After one year, the transplanted thalli were collected and analyzed by using Instrumental Activation Analysis, complemented with Atomic Absorption Spectrophotometry for the Pb content determination. Crustal inputs were identified by computing enrichment factors. The transplanted thalli concentrations of most of the elements under study, Al, As, Ba, Ce, Co, Cr, Dy, Eu, Hg, Fe, La, Lu, Mn, Na, Pb, Sb, Sc, Sm, Sr, Tb, Ti, Th, V, Yb and Zn, showed no significant differences with respect to the control thalli. However, some biological elements, Ca, Cl, Br, K and Rb, showed significant variations with respect to the controls, more noticeable in the first two elements. (author) 18 refs., 1 fig., 2 tabs.

  18. Economic Instruments and the Pollution Impact of the 2006-2010 Vietnam Socio-Economic Development Plan

    OpenAIRE

    Jensen, Henning Tarp; Tarp, Finn; Hong, Vu Xuan Nguyet; Man Hai, Nguyen; Thanh, Le Ha

    2008-01-01

    The current study derives optimal growth paths for pollution emission charges, in order to control future water pollution emissions in the Vietnamese manufacturing sector. The study builds on a prior study, which estimated the manufacturing sector pollution impact of the 2006- 2010 SEDP development plan for Vietnam (Jensen et al.; 2008). The current study demonstratesthat effective implementation and moderate expansion of optimal emission charges, under certain conditions, could have been use...

  19. Development and validation of an instrument to measure the impact of genetic testing on self-concept in Lynch syndrome.

    Science.gov (United States)

    Esplen, M J; Stuckless, N; Gallinger, S; Aronson, M; Rothenmund, H; Semotiuk, K; Stokes, J; Way, C; Green, J; Butler, K; Petersen, H V; Wong, J

    2011-11-01

    A positive genetic test result may impact on a person's self-concept and affect quality of life. The purpose of the study was to develop a self-concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer Lynch syndrome (LS). Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors, which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers, Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. A 20-item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale showed excellent reliability (Cronbach's α = 0.93), good convergent validity by a high correlation with impact of event scale (r(102) = 0.55, p Rosenberg self-esteem scale (r(108) = -0.59, p scale's performance was stable across participant characteristics. This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies. © 2011 John Wiley & Sons A/S.

  20. Use of portable instrumentation/PC for loose-part monitor sensor validation, impact detection, and characterization

    International Nuclear Information System (INIS)

    Allen, J.W.

    1989-01-01

    Impact detection [loose-part monitoring (LPM)] is typically performed using acoustic sensors (accelerometers) permanently affixed to natural collection sites for possible loose parts. A typical nuclear facility will consist of 12 to 16 channels around the primary loop. Normal operation of these systems consists of continuously monitoring the conditioned sensor output and alert (or alarm) when signal levels exceed a certain threshold value. Technology for Energy Corporation (TEC) has utilized statistical methods to develop a system for monitoring LPM sensors that is capable of unambiguous channel operability validation, low-level impact (rattling) detection and trending, and impact characterization. The system consists of a software package resident on a personal computer (PC) for data storage, trending, and reporting. A small portable microprocessor box (meter) is used for data acquisition and analysis. The portable data box receives an analysis parameter set from the host PC, accepts amplified signals from the individual LPM sensors, and carries out spectral and probability density analyses. The results from the analyses are available for viewing at the meter and are locally stored for later uploading to the host computer. At the host, key parameters are trended from both the spectral and the amplitude probability function analyses. Alarm limits are preset to indicate if further analysis is warranted

  1. Failure mechanism of resistance-spot-welded specimens impacted on base material by bullets

    Directory of Open Access Journals (Sweden)

    Chunlei Fan

    2018-01-01

    Full Text Available The tests of bullet impact on the base material (BM of a simple specimen with a single resistance-spot-welded (RSW nugget of TRIP800 steel are performed to investigate the response of the RSW specimen to the ballistic debris impact on the RSW specimen. A one-stage gas gun is used to fire the bullets while a laser velocity interferometer system for any reflector (VISAR is used to measure the velocity histories of the free surfaces of the RSW specimen. The recovered RSW specimens are examined with the three-dimensional super depth digital microscope (SDDM and the scanning electro microscope (SEM. For the tests of small multiple-bullet impact, it is revealed that the wave train of the VISAR measured results and the detachment of the base material interfaces in the recovered RSW specimens are directly related to the reflection and refraction of the curved stress waves incoming to the interfaces and the free surfaces in the RSW specimens. The detachment of BM interfaces can lead to the impact failure of the RSW joints for the larger multiple-bullet impact at higher velocity, the mechanism of which is different from the case for normal incidence (spalling. For the tests of single large bullet impact, it is brought to light experimentally that the plastic strain concentration at the “notch tip” spurs either the crack near the RSW joint or the split of the nugget. The numerical simulation shows up the process of splitting the nugget: a crack initiates at the “notch tip”, propagates across the nugget interface and splits the nugget into two parts. It is indicated that the interaction between the stress waves and many interfaces/free surfaces in the RSW specimen under ballistic impact causes variable local stress triaxialities and stress Lode angles, which affects the deformation and fracture mechanism of the RSW specimen including stretching and shearing failure. It is shown that the impact failure of the RSW joints is a mixture of brittle

  2. Failure mechanism of resistance-spot-welded specimens impacted on base material by bullets

    Science.gov (United States)

    Fan, Chunlei; Ma, Bohan; Chen, Danian; Wang, Huanran; Ma, Dongfang

    2018-01-01

    The tests of bullet impact on the base material (BM) of a simple specimen with a single resistance-spot-welded (RSW) nugget of TRIP800 steel are performed to investigate the response of the RSW specimen to the ballistic debris impact on the RSW specimen. A one-stage gas gun is used to fire the bullets while a laser velocity interferometer system for any reflector (VISAR) is used to measure the velocity histories of the free surfaces of the RSW specimen. The recovered RSW specimens are examined with the three-dimensional super depth digital microscope (SDDM) and the scanning electro microscope (SEM). For the tests of small multiple-bullet impact, it is revealed that the wave train of the VISAR measured results and the detachment of the base material interfaces in the recovered RSW specimens are directly related to the reflection and refraction of the curved stress waves incoming to the interfaces and the free surfaces in the RSW specimens. The detachment of BM interfaces can lead to the impact failure of the RSW joints for the larger multiple-bullet impact at higher velocity, the mechanism of which is different from the case for normal incidence (spalling). For the tests of single large bullet impact, it is brought to light experimentally that the plastic strain concentration at the "notch tip" spurs either the crack near the RSW joint or the split of the nugget. The numerical simulation shows up the process of splitting the nugget: a crack initiates at the "notch tip", propagates across the nugget interface and splits the nugget into two parts. It is indicated that the interaction between the stress waves and many interfaces/free surfaces in the RSW specimen under ballistic impact causes variable local stress triaxialities and stress Lode angles, which affects the deformation and fracture mechanism of the RSW specimen including stretching and shearing failure. It is shown that the impact failure of the RSW joints is a mixture of brittle fracture and ductile

  3. Development of mechanisms and instruments of increasing economic safety with regard to the peculiarities of the present stage of the economy

    Directory of Open Access Journals (Sweden)

    Yu. M. Sokolinskaya

    2017-01-01

    Full Text Available The development of theoretical provisions of economic security, their mechanisms and instruments is determined by the laws of the economy that reveal the management of production, the market processes of distribution, exchange, consumption, taking into account the features of industries, regions, the level of globalization, etc. Each sphere, region or branch of the economy is characterized by peculiar economic processes justified by a specific approach to their disclosure. Economic security, its emergence, development and adaptation to changing market conditions, is based on the information economy or on the knowledge economy. Economic security is determined by the costs of information, its confidentiality, taking into account the interaction, on the one hand, and the competition of various enterprises, regions and countries, on the other. In the process of economic development, knowledge in general and any specialists are needed, but only those that are necessary in the economy. Communication and interaction of science, knowledge, information with production provides not only economic security, but also their successful development. To develop certain principles or laws for the interaction of technological and economic factors, their degree and level of interaction, a study of economic activity was conducted. In the present study, a civilizational approach was used that is based on the determining role of man in the economy and society and the importance of knowledge and information, when the important mechanisms remain: the development of technology and technology, the role of knowledge and information, and communication. The implementation of the civilized approach takes into account the new methodological level of increasing economic security, when the main factor in the development of the economy is the scientific and technological progress that justifies the information path of economic development.

  4. Clinical and microbiological effects of mechanical instrumentation and local antimicrobials during periodontal supportive therapy in aggressive periodontitis patients: smoker versus non-smoker patients.

    Science.gov (United States)

    Guarnelli, Maria Elena; Farina, Roberto; Cucchi, Alessandro; Trombelli, Leonardo

    2010-11-01

    To compare the clinical and microbiological effects of ultrasonic mechanical instrumentation (UMI) associated to home-care use of amine fluoride/stannous fluoride (AmF/SnF(2) )-containing mouthrinse and toothpaste in smoker and non-smoker patients affected by generalized aggressive periodontitis (G-AgP) during a recall session of supportive periodontal therapy (SPT). Thirteen smokers and 25 non-smokers G-AgP patients enrolled in an SPT programme received a single session of UMI associated with home-care use of AmF/SnF(2) -containing mouthrinse and toothpaste. Clinical and microbiological parameters were assessed pre-treatment, at 6 and 12 weeks post-treatment. In both groups, UMI plus AmF/SnF(2) -implemented oral hygiene use determined a significant decrease of total bacterial counts, with non-smokers exhibiting a lower count compared with smokers at 12 weeks. No significant differences were observed between smokers and non-smokers in the counts of total pathogens and red complex species at each observation interval. Clinically, a significant reduction of supragingival plaque, gingival inflammation and probing pocket depth was similarly observed in both groups. A combined mechanical/chemical plaque control approach based on UMI and the use of AmF/SnF(2) agents resulted in the reduction of supragingival plaque deposits, gingival inflammation and subgingival periodontal pathogens in G-AgP patients during SPT, with no substantial difference between smokers and non-smokers. © 2010 John Wiley & Sons A/S.

  5. Subnanogram proteomics: Impact of LC column selection, MS instrumentation and data analysis strategy on proteome coverage for trace samples

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Ying; Zhao, Rui; Piehowski, Paul D.; Moore, Ronald J.; Lim, Sujung; Orphan, Victoria J.; Paša-Tolić, Ljiljana; Qian, Wei-Jun; Smith, Richard D.; Kelly, Ryan T.

    2018-04-01

    One of the greatest challenges for mass spectrometry (MS)-based proteomics is the limited ability to analyze small samples. Here we investigate the relative contributions of liquid chromatography (LC), MS instrumentation and data analysis methods with the aim of improving proteome coverage for sample sizes ranging from 0.5 ng to 50 ng. We show that the LC separations utilizing 30-µm-i.d. columns increase signal intensity by >3-fold relative to those using 75-µm-i.d. columns, leading to 32% increase in peptide identifications. The Orbitrap Fusion Lumos mass spectrometer significantly boosted both sensitivity and sequencing speed relative to earlier generation Orbitraps (e.g., LTQ-Orbitrap), leading to a ~3× increase in peptide identifications and 1.7× increase in identified protein groups for 2 ng tryptic digests of bacterial lysate. The Match Between Runs algorithm of open-source MaxQuant software further increased proteome coverage by ~ 95% for 0.5 ng samples and by ~42% for 2 ng samples. The present platform is capable of identifying >3000 protein groups from tryptic digestion of cell lysates equivalent to 50 HeLa cells and 100 THP-1 cells (~10 ng total proteins), respectively, and >950 proteins from subnanogram bacterial and archaeal cell lysates. The present ultrasensitive LC-MS platform is expected to enable deep proteome coverage for subnanogram samples, including single mammalian cells.

  6. Adolescent Corticosterone and TrkB Pharmaco-Manipulations Sex-Dependently Impact Instrumental Reversal Learning Later in Life

    Directory of Open Access Journals (Sweden)

    Elizabeth T. Barfield

    2017-12-01

    Full Text Available Early-life trauma can increase the risk for, and severity of, several psychiatric illnesses. These include drug use disorders, and some correlations appear to be stronger in women. Understanding the long-term consequences of developmental stressor or stress hormone exposure and possible sex differences is critically important. So-called “reversal learning” tasks are commonly used in rodents to model cognitive deficits in stress- and addiction-related illnesses in humans. Here, we exposed mice to the primary stress hormone corticosterone (CORT during early adolescence (postnatal days 31–42, then tested behavioral flexibility in adulthood using an instrumental reversal learning task. CORT-exposed female, but not male, mice developed perseverative errors. Despite resilience to subchronic CORT exposure, males developed reversal performance impairments following exposure to physical stressors. Administration of a putative tyrosine kinase receptor B (trkB agonist, 7,8-dihydroxyflavone (7,8-DHF, during adolescence blocked CORT-induced errors in females and improved performance in males. Conversely, blockade of trkB by ANA-12 impaired performance. These data suggest that trkB-based interventions could have certain protective benefits in the context of early-life stressor exposure. We consider the implications of our findings in an extended “Discussion” section.

  7. A strain-controlled RheoSANS instrument for the measurement of the microstructural, electrical, and mechanical properties of soft materials

    Science.gov (United States)

    Richards, Jeffrey J.; Wagner, Norman J.; Butler, Paul D.

    2017-10-01

    In situ measurements are an increasingly important tool to inform the complex relationship between nanoscale properties and macroscopic material measurements. Knowledge of these phenomena can be used to develop new materials to meet the performance demands of next generation technologies. Conductive complex fluids have emerged as an area of research where the electrical and mechanical properties are key design parameters. To study the relationship between microstructure, conductivity, and rheology, we have developed a small angle neutron scattering (SANS) compatible Couette rheological geometry capable of making impedance spectroscopy measurements under continuous shear. We have also mounted this geometry on a commercial strain controlled rheometer with a modified forced convection oven. In this manuscript, we introduce the simultaneous measurement of impedance spectroscopy, rheological properties and SANS data. We describe the validation of this dielectric RheoSANS instrument and demonstrate its operation using two systems—an ion gel comprising Pluronic® surfactant and ionic liquid, ethyl-ammonium nitrate, and poly(3-hexylthiophene) organogel prepared in a mixture of hexadecane and dichlorobenzene. In both systems, we use this new measurement capability to study the microstructural state of these materials under two different protocols. By monitoring their dielectric rheology at the same time as the SANS measurement, we demonstrate the capacity to directly probe structure-property relationships inherent to the macroscopic material response.

  8. Development of innovation complexes as a mechanism of technologies transfer and an instrument of social-economic policy in the region

    Directory of Open Access Journals (Sweden)

    A. F. Sukhovey

    2010-09-01

    Full Text Available In this article is developed a role of innovation complexes of a region at the base of analysis of foreign and domestic experience of organization science-technological complexes. Main reasons, braking innovation transformations in Russia are cleared. For example of Russia it is shown, that unsystematic forming objects of innovation infrastructure without interaction with needs of development region and state its science-technical and industrial potential do not taken to positive change at economy and do not help to activation of innovation processes. Peculiarity different innovation complexes as instrument of social-economic policy, its participation at decision, those actual problems as overcoming of decline traditional branches of industry, forming high-tech sector, rise of outlaying districts, rise of competitive ability of industry were cleared. It is given special attention to possibility of innovation complexes as effective mechanism passing of technologies, allowing to create favorable conditions to subjects of innovation activity and to speed up process “research — production”. Measures to foundation of effective innovation infrastructure as one conditions of acceleration innovation development in Russia are offered.

  9. Differential effects of MPEP and diazepam in tests of conditioned emotional response and Pavlovian-to-instrumental transfer suggests 'anxiolytic' effects are mediated by different mechanisms.

    Science.gov (United States)

    George, S A; Hutson, P H; Stephens, D N

    2009-06-01

    The selective mGluR5 antagonist 2-methyl-6-(phenylethynyl)-pyridine (MPEP) is reported to be anxiolytic in several animal models of anxiety, including the conditioned emotional response (CER) paradigm. Suppression of responding during conditioned stimulus (CS) presentation in CER may reflect behavioural competition between lever pressing and adopting a shock-avoidance posture, or it may alternatively reflect altered value of the food reward following its association with a footshock, thus reducing its ability to motivate responding. If this is the case, then drugs that reduce the CER may interfere with the mechanism by which CSs are able to motivate responding, rather than by reducing anxiety. The standard test of the ability of Pavlovian cues to motivate responding is the Pavlovian-to-instrumental transfer (PIT) paradigm and it has recently been suggested that CER may be 'negative PIT'. We compared the effect of MPEP (0, 3, 10 and 30 mg/kg) and diazepam (0, 1, 3 and 10 mg/kg) in CER and PIT. Both MPEP and diazepam significantly reduced conditioned suppression in the CER paradigm. MPEP, but not diazepam, significantly reduced PIT. The findings support the hypothesis that MPEP may reduce expression of anxiety in the CER paradigm by interfering with the way in which emotionally salient cues are able to affect behaviour, but do not support such an analysis of the effect of diazepam. Diazepam and MPEP may therefore achieve their effects in CER by influencing different psychological processes.

  10. Design of efficient loadcell for measurement of mechanical impact by piezoelectric PVDF film sensor

    Directory of Open Access Journals (Sweden)

    Priyanka Guin

    2016-09-01

    Full Text Available Conversion efficiency of mechanical impact into electrical voltage remains ever increasing demand for piezoelectric PVDF film sensor. For a given film sensor, the output voltage produced due to mechanical impact is highly dependent on the direction of stretching (or compressing and active area of the film sensor. More is the active area of the film; higher will be the output voltage. It is shown that the active area is significantly increased due to the ridge-like shape given at the inner surfaces of the plates of sandwich type loadcell and as a result of which higher conversion efficiency is obtained. The effectiveness of the ridge-like shape is confirmed statistically by conducting two factorial design of experiment in which shape and material of the loadcell are considered as the two factors with 2×4 matrix. In case of loadcell made of glass plates, more than 100% increase in the output voltage is observed for ridge-like shape in comparison to its plain counterpart. Both the bandwidth and frequency range of the output signal is found to be independent and dependent of the loadcell materials for indirect and direct impact with the loadcell respectively. The merits and demerits of the fabricated loadcells are discussed.

  11. Bone hyperalgesia after mechanical impact stimulation: a human experimental pain model.

    Science.gov (United States)

    Finocchietti, Sara; Graven-Nielsen, Thomas; Arendt-Nielsen, Lars

    2014-12-01

    Hyperalgesia in different musculoskeletal structures including bones is a major clinical problem. An experimental bone hyperalgesia model was developed in the present study. Hyperalgesia was induced by three different weights impacted on the shinbone in 16 healthy male and female subjects. The mechanical impact pain threshold (IPT) was measured as the height from which three weights (165, 330, and 660 g) should be dropped to elicit pain at the shinbone. Temporal summation of pain to repeated impact stimuli was assessed. All these stimuli caused bone hyperalgesia. The pressure pain threshold (PPT) was assessed by a computerized pressure algometer using two different probes (1.0 and 0.5 cm(2)). All parameters were recorded before (0), 24, 72, and 96 h after the initial stimulations. The IPTs were lowest 24 h after hyperalgesia induction for all three weights and the effect lasted up to 72 h (p pain and hyperalgesia model may provide the basis for studying this fundamental mechanism of bone-related hyperalgesia and be used for profiling compounds developed for this target.

  12. Antiretroviral therapy (ART) rationing and access mechanisms and their impact on youth ART utilization in Malawi.

    Science.gov (United States)

    Dixon, Jimmy-Gama; Gibson, Sarah; McPake, Barbara; Maleta, Ken

    2011-06-01

    The World Health Organization (WHO) staging is a commonly used rationing mechanism for highly active antiretroviral therapy (HAART) among various HIV infected populations including youths in most developing countries. Rationing is defined as any policy or practice that restricts consumption of or access to certain goods due to its limited supply. However, as HIV prevalence is rapidly increasing among youth, understanding the capacity of the staging approach to achieve HAART uptake in youth is of considerable importance. This study aimed to explore how HAART rationing and access mechanisms impact on youth's utilization of HAART in Malawi. The study used mixed methods with quantitative analysis of existing Ministry of Health Clinical HIV Unit data used to determine existing levels of youth HAART use. Qualitative methods employed in-depth interviews that interviewed nine ART providers, nine HIV positive youth on HAART and nine HIV positive youth not on HAART; and field observations to nine ART clinics were used to understand HAART rationing and access mechanisms and how such mechanisms impact youth uptake of HAART. The findings revealed that ART providers use both explicit rationing mechanisms like WHO clinical staging and implicit rationing mechanisms like use of waiting lists, queues and referral in ART provision. However, the WHO staging approach had some challenges in its implementation. It was also observed that factors like non-comprehensive approach to HAART provision, costs incurred to access HAART, negative beliefs and misconceptions about HAART and HIV were among the key factors that limit youth access to HAART. The study recommends that while WHO staging is successful as a rationing mechanism in Malawi, measures should be put in place to improve access to CD4 assessment for clients who may need it. ART providers also need to be made aware of the implicit rationing mechanisms that may affect HAART access. There is also need to improve monitoring of those HIV

  13. Economic Instruments and the Pollution Impact of the 2006-2010 Vietnam Socio-Economic Development Plan

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Tarp, Finn; Xuan, Hong Vu

    plan for Vietnam (Jensen et al.; 2008). The current study demonstratesthat effective implementation and moderate expansion of optimal emission charges, under certain conditions, could have been used, as part of the 2006-2010 SEDP development plan, to control pollution emissions at 2005 levels. Moreover...... plans, in order to control pollution emissions as development progresses in Vietnam.......The current study derives optimal growth paths for pollution emission charges, in order to control future water pollution emissions in the Vietnamese manufacturing sector. The study builds on a prior study, which estimated the manufacturing sector pollution impact of the 2006- 2010 SEDP development...

  14. Mechanical characteristics of plastic base Ports and impact on flushing efficacy

    Directory of Open Access Journals (Sweden)

    Guiffant G

    2017-01-01

    Full Text Available Gérard Guiffant,1 Patrice Flaud,1 Laurent Royon,1 Espérie Burnet,2 Jacques Merckx1–3 1University Paris Diderot, Biofluidic Group, UMR CNRS, 2Pulmonary Department and Adult Cystic Fibrosis Centre, Cochin Hospital, 3University Teaching Hospital, Necker-Enfants Malades, Paris, France Background: Three types of totally implantable venous access devices, Ports, are currently in use: titanium, plastic (polyoxymethylene, POM, and mixed (titanium base with a POM shell. Physics theory suggests that the interaction between a non-coring needle (NCN, made of stainless steel and a plastic base would lead to the stronger material (steel altering the more malleable material (plastic. Objectives: To investigate whether needle impacts can alter a plastic base’s surface, thus potentially reducing flushing efficacy. Study design and methods: A Port made of POM was punctured 200 times with a 19-gauge NCN. Following the existing guidelines, the needle tip pricked the base with each puncture. The Port’s base was then examined using a two-dimensional optical instrument, and a bi-dimensional numerical simulation using COMSOL® was performed to investigate potential surface irregularities and their impact on fluid flow. Results: Each needle impact created a hole (mean depth, 0.12 mm with a small bump beside it (mean height, 0.02 mm the Reynolds number Rek≈10. A numerical simulation of the one hole/bump set showed that the flushing efficacy was 60% that of flushing along a flat surface. Discussion: In clinical practice, the number of times a Port is punctured depends on patient and treatment characteristics, but each needle impact on the plastic base may increase the risk of decreased flushing effectiveness. Therefore, the more a plastic Port is accessed, the greater the risk of microorganisms, blood products, and medication accumulation. Conclusions: Multiple needle impacts created an irregular surface on the Port’s base, which decreased flushing efficacy

  15. High-Precision Locations and the Stress Field from Instrumental Seismicity, Moment Tensors, and Short-Period Mechanisms through the Mina Deflection, Central Walker Lane

    Science.gov (United States)

    Ruhl, C. J.; Smith, K. D.

    2012-12-01

    The Mina Deflection (MD) region of the central Walker Lane of eastern California and western Nevada, is a complex zone of northeast-trending normal, and primarily left-lateral strike-slip to oblique-slip faulting that separates the Southern Walker Lane (SWL) from a series of east-tilted normal fault blocks in the Central Walker Lane (CWL) (Faulds and Henry, 2008; Surpless, 2008). The MD accommodates the transfer of right-lateral strike-slip motion from northwest-striking faults in the SWL to a series of left-stepping northwest-striking right-lateral strike-slip faults in the CWL, east of the Wassuk Range near Hawthorne, NV. The ~50 km wide ~80 km long right-step is a distinct transition in regional physiography that has been attributed to strain accommodation through pre-Cenozoic lithospheric structures. Several slip transfer mechanisms have been proposed within the MD, from clockwise rotation of high-angle fault blocks (Wesnousky, 2005), to low-angle displacement within the Silver Peak-Lone Mountain complex (Oldow et al., 2001), and curved fault arrays associated with localized basins and tectonic depressions (Ferranti et al., 2009). The region has been a regular source of M4+ events, the most recent being an extended sequence that included twenty-seven M 3.5+ earthquakes (largest event M 4.6) south of Hawthorne in 2011. These earthquakes (Mina, NV, and the 1932 M 7.1 Cedar Mountains earthquake east of the Pilot Mountains. Another persistent feature in the seismicity is an ~40 km long arcuate distribution of activity extending from approximately Queen Valley, north of the White Mountains, to Mono Lake that appears to reflect a southwestern boundary to northeast-striking structures in the MD. Here we develop high-precision relocations of instrumental seismicity in the MD from 1984 through 2012, including relocations of the 2004 sequence, and account for the historical seismic record. MT solutions from published reports and computed from recent M 3.5+ earthquakes as

  16. Instrumentation development

    International Nuclear Information System (INIS)

    Ubbes, W.F.; Yow, J.L. Jr.

    1988-01-01

    Instrumentation is developed for the Civilian Radioactive Waste Management Program to meet several different (and sometimes conflicting) objectives. This paper addresses instrumentation development for data needs that are related either directly or indirectly to a repository site, but does not touch on instrumentation for work with waste forms or other materials. Consequently, this implies a relatively large scale for the measurements, and an in situ setting for instrument performance. In this context, instruments are needed for site characterization to define phenomena, develop models, and obtain parameter values, and for later design and performance confirmation testing in the constructed repository. The former set of applications is more immediate, and is driven by the needs of program design and performance assessment activities. A host of general technical and nontechnical issues have arisen to challenge instrumentation development. Instruments can be classed into geomechanical, geohydrologic, or other specialty categories, but these issues cut across artificial classifications. These issues are outlined. Despite this imposing list of issues, several case histories are cited to evaluate progress in the area

  17. Dynamic and impact contact mechanics of geologic materials: Grain-scale experiments and modeling

    International Nuclear Information System (INIS)

    Cole, David M.; Hopkins, Mark A.; Ketcham, Stephen A.

    2013-01-01

    High fidelity treatments of the generation and propagation of seismic waves in naturally occurring granular materials is becoming more practical given recent advancements in our ability to model complex particle shapes and their mechanical interaction. Of particular interest are the grain-scale processes that are activated by impact events and the characteristics of force transmission through grain contacts. To address this issue, we have developed a physics based approach that involves laboratory experiments to quantify the dynamic contact and impact behavior of granular materials and incorporation of the observed behavior indiscrete element models. The dynamic experiments do not involve particle damage and emphasis is placed on measured values of contact stiffness and frictional loss. The normal stiffness observed in dynamic contact experiments at low frequencies (e.g., 10 Hz) are shown to be in good agreement with quasistatic experiments on quartz sand. The results of impact experiments – which involve moderate to extensive levels of particle damage – are presented for several types of naturally occurring granular materials (several quartz sands, magnesite and calcium carbonate ooids). Implementation of the experimental findings in discrete element models is discussed and the results of impact simulations involving up to 5 × 105 grains are presented.

  18. Dynamic and impact contact mechanics of geologic materials: Grain-scale experiments and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Cole, David M.; Hopkins, Mark A.; Ketcham, Stephen A. [Engineer Research and Development Center - Cold Regions Research and Engineering Laboratory, 72 Lyme Rd., Hanover, NH 03755 (United States)

    2013-06-18

    High fidelity treatments of the generation and propagation of seismic waves in naturally occurring granular materials is becoming more practical given recent advancements in our ability to model complex particle shapes and their mechanical interaction. Of particular interest are the grain-scale processes that are activated by impact events and the characteristics of force transmission through grain contacts. To address this issue, we have developed a physics based approach that involves laboratory experiments to quantify the dynamic contact and impact behavior of granular materials and incorporation of the observed behavior indiscrete element models. The dynamic experiments do not involve particle damage and emphasis is placed on measured values of contact stiffness and frictional loss. The normal stiffness observed in dynamic contact experiments at low frequencies (e.g., 10 Hz) are shown to be in good agreement with quasistatic experiments on quartz sand. The results of impact experiments - which involve moderate to extensive levels of particle damage - are presented for several types of naturally occurring granular materials (several quartz sands, magnesite and calcium carbonate ooids). Implementation of the experimental findings in discrete element models is discussed and the results of impact simulations involving up to 5 Multiplication-Sign 105 grains are presented.

  19. Mechanical and fracture properties at impact loading of selected steels for nuclear power engineering

    International Nuclear Information System (INIS)

    Buchar, J.; Bilek, Z.

    1988-01-01

    The possibilities are briefly characterized of experimental research of mechanical and fracture properties of steels used in nuclear power engineering. Attention is paid to plastic deformation and the assessment of fracture formation during impact loading. The results are reported for steels 15Kh2MFA and 10GN2MFA. For steel 15Kh2MFA the effect was also studied of neutron radiation at different temperatures. From the theory developed for non-irradiated material 10GN2MFA, a prediction is made within the original model of the fracture stress value for steel 15Kh2MFA in both non-irradiated and irradiated states. The conclusion is arrived at that the existing methods of assessing steel properties at impact load allow obtaining knowledge of all significant effects during actual stress, this using only small specimens of the materials. (Z.M.). 4 figs., 8 refs

  20. Evaluation of environmental impacts during chemical mechanical polishing (CMP) for sustainable manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Seop; Park, Sun Joon; Jeong, Hae Do [Pusan National University, Busan (Korea, Republic of)

    2013-02-15

    Reducing energy consumption has become a critical issue in manufacturing. The semiconductor industry in particular is confronted with environmental regulations on pollution associated with electric energy, chemical, and ultrapure water (UPW) consumptions. This paper presents the results of an evaluation of the environmental impacts during chemical mechanical polishing (CMP), a key process for planarization of dielectrics and metal films in ultra-large-scale integrated circuits. The steps in the CMP process are idling, conditioning, wetting, wafer loading/unloading, head dropping, polishing, and rinsing. The electric energy, CMP slurry, and UPW consumptions associated with the process and their impacts on global warming are evaluated from an environmental standpoint. The estimates of electric energy, slurry, and UPW consumptions as well as the associated greenhouse gas emissions presented in this paper will provide a technical aid for reducing the environmental burden associated with electricity consumption during the CMP process.

  1. Design of instrumentation and software for precise laser machining

    Science.gov (United States)

    Wyszyński, D.; Grabowski, Marcin; Lipiec, Piotr

    2017-10-01

    The paper concerns the design of instrumentation and software for precise laser machining. Application of advanced laser beam manipulation instrumentation enables noticeable improvement of cut quality and material loss. This factors have significant impact on process efficiency and cutting edge quality by means of machined part size and shape accuracy, wall taper, material loss reduction (e.g. diamond) and time effectiveness. The goal can be reached by integration of laser drive, observation and optical measurement system, beam manipulation system and five axis mechanical instrumentation with use of advanced tailored software enabling full laser cutting process control and monitoring.

  2. Indirect mechanisms in electron-impact ionization of multiply charged ions

    International Nuclear Information System (INIS)

    Phaneuf, R.A.; Gregory, D.C.

    1986-09-01

    The important role of indirect-ionization mechanisms in electron-impact ionization of multiply charged ions has been emphasized by some recent experiments conducted with the ORNL-ECR multicharged ion source. Illustrative examples of investigations of the Mg-isoelectronic and Fe-isonuclear sequences are presented and compared with the results of detailed theoretical calculations. New experimental data is also presented concerning the role of resonance effects in the ionization of Li-like O 5+ and Na-like Fe 15+ ions

  3. Grid Faults Impact on the Mechanical Loads of Active Stall Wind Turbine

    DEFF Research Database (Denmark)

    Iov, Florin; Cutululis, Nicolaos A.; Hansen, Anca D.

    2008-01-01

    Emphasis in this paper is on the fault ride-through operation impact on the wind turbines structural loads. Grid faults are typically simulated in power system simulation tools using simplified drive train mechanical model, approach which doesn't allow a thorough investigation of structural loads...... as the electrical design of the wind turbine response during grid faults. The two-step simulation procedure is assessed by means of a simulation example. The effect of a grid fault on the structural part of a typical fixed speed wind turbine, equipped with an induction generator, is assessed....

  4. Research on Mechanical Behaviors of Micro-crystal Muscovite/UHMWPE Composites to Impact Loading

    Directory of Open Access Journals (Sweden)

    Hu Huarong

    2016-01-01

    Full Text Available UHMWPE composites were prepared by hot pressing process with micro-crystal muscovite as reinforced particulates. The mechanical behaviors of composites to impact loading was evaluated by split Hopkinson bar. The results demonstrated that dynamic yield stress and failure stress of UHMWPE composites were gradually increased when the filling amount was less than 20%; when the filling content of muscovite was around 15%, the energy absorption efficiency of the composite reaches maximum value. It was also found that when strain rate within 3200/s, the dynamic yield stress, failure stress and energy absorption efficiency of UHMWPE composites increased with the increase of strain rate and display strain rate enhancement effect.

  5. AMOC decadal variability in Earth system models: Mechanisms and climate impacts

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, Alexey [Yale Univ., New Haven, CT (United States)

    2017-09-06

    This is the final report for the project titled "AMOC decadal variability in Earth system models: Mechanisms and climate impacts". The central goal of this one-year research project was to understand the mechanisms of decadal and multi-decadal variability of the Atlantic Meridional Overturning Circulation (AMOC) within a hierarchy of climate models ranging from realistic ocean GCMs to Earth system models. The AMOC is a key element of ocean circulation responsible for oceanic transport of heat from low to high latitudes and controlling, to a large extent, climate variations in the North Atlantic. The questions of the AMOC stability, variability and predictability, directly relevant to the questions of climate predictability, were at the center of the research work.

  6. Investigation of sheet steel St 37.2 under mechanical impact

    International Nuclear Information System (INIS)

    Berg, H.P.; Brennecke, P.; Koester, R.; Friehmelt, V.

    1990-01-01

    Special waste originating, e.g. from chemical industry and radioactive wastes are emplaced in disposal mines. Slinger stowing is an approved technique to fill up residual voids in emplacement rooms. If it should be applied, possible mechanical loads on the integrity of sheet steel containers have to be considered. By theoretical calculations and by experiments under variation of different parameters using test specimen and backfill material from the Konrad mine using the container type V as an example it has been shown that sheet steel St 37.2 with a wall thickness of 3 mm will withstand mechanical impact imposed by backfill particles having a speed of 24 m/s. (orig.) [de

  7. IMPACT OF NANOMODIFIERS ON MECHANICAL AND PHYSICAL PROPERTIES OF GYPSUM BINDERS

    Directory of Open Access Journals (Sweden)

    DEREVIANKO V. N.

    2017-02-01

    Full Text Available Summary. Problem statement. In the next 10 years, more than 90% of materials will be replaced with new materials – nanocomposites [1]. The nanocomponents application will allow manufacture of high-strength materials with reduced production cost and will ensure demand for products [2]. Researches aimed to determination of carbon nanotube type nanomodifier concentration impact on the physical and mechanical properties of gypsum binders are important today and must result in creation of competitive strong nano-materials. Purpose. Research of carbon nanotube (CNT type nanomodifier concentration impact on the physical and mechanical properties of gypsum binders. Conclusion. Sample microstructure analysis revealed that the non-modified gypsum sample structure is dominated by prismatic and lamellar crystals randomly distributed throughout the matrix volume. In this case, loose structure with increased porosity is formed, which results in sample mechanical strength reduction. In the CNT-modified gypsum matrix, well-ordered and homogeneous structure is formed with larger needle-shaped crystals, which results in the phase-contacting area increase, porosity reduction and thus the physical and mechanical characteristics improvement. It is experimentally proved that at the identical nano-modifier content in the gypsum matrix (0.035 %, maximum compression strength gain is achieved with the use of CNT and makes 28- 30%. At the use of initial carbon nanotubes, increase in strength at the same nano-modifier content makes 13-15%. The Ca2+ ions interaction with the graphene-like carbon surface was investigated by the DFT method. Capability is demonstrated of the covalent calcium bonding with the hexagonal carbon surface cell as a result of overlap of Ca2+ valence 3p orbitals and carbon 2р orbitals.

  8. Aircraft Instrument, Fire Protection, Warning, Communication, Navigation and Cabin Atmosphere Control System (Course Outline), Aviation Mechanics 3 (Air Frame): 9067.04.

    Science.gov (United States)

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to familiarize the student with manipulative skills and theoretical knowledge concerning aircraft instrument systems like major flight and engine instruments; fire protection and fire fighting systems; warning systems and navigation systems; aircraft cabin control systems, such as…

  9. Impact of Carbon Quota Allocation Mechanism on Emissions Trading: An Agent-Based Simulation

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2016-08-01

    Full Text Available This paper establishes an agent-based simulation system of the carbon emissions trading in accordance with the complex feature of the trading process. This system analyzes the impact of the carbon quota allocation mechanism on emissions trading for three different aspects including the amount of emissions reduction, the economic effect on the emitters, and the emissions reduction cost. Based on the data of the carbon emissions of different industries in China, several simulations were made. The results indicate that the emissions trading policy can effectively reduce carbon emissions in a perfectly competitive market. Moreover, by comparing separate quota allocation mechanisms, we obtain the result that the scheme with a small extent quota decrease in a comprehensive allocation mechanism can minimize the unit carbon emission cost. Implementing this scheme can also achieve minimal effects of carbon emissions limitation on the economy on the basis that the environment is not destroyed. However, excessive quota decrease cannot promote the emitters to reduce emission. Taking into account that several developing countries have the dual task of limiting carbon emissions and developing the economy, it is necessary to adopt a comprehensive allocation mechanism of the carbon quota and increase the initial proportion of free allocation.

  10. Impact of radiation exposure on mechanical and superconducting properties of Bi-2212 superconductor ceramics

    International Nuclear Information System (INIS)

    Azlan Abdul Rahman; Nasri Abdul Hamid; Abdul Aziz Mohamed; Mohd Shahrul Nizam Abdullah; Samsul Isman; Hidayah Zainal

    2013-01-01

    Full-text: For practical applications of high-temperature superconductor ceramics, the compounds must be able to sustain extreme mechanical stress and external magnetic field. Bi-2212 superconductor is one of the existing superconductors that are commonly used in various applications. Improvement in the microstructure enhanced the connectivity of the adjacent grains within the superconducting grains, and as such improved the mechanical strength of the ceramics. The ability of the superconductor ceramics to sustain superconducting properties in external magnetic field is also required. The compounds must be able to maintain high transport critical current density (Jc) in magnetic field. Another potential application of superconductors is at the nuclear facilities. Thus, study on the impact of radiation exposure on the mechanical and superconducting properties is very important to gauge the viability of superconductor ceramics in such environment. In this study, the mechanical and superconducting properties between exposure and non-irradiated samples are compared. Characterization will be done by the temperature dependence on electrical resistance measurements, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and measurements of transport critical current (Jc) dependence on temperature in magnetic field. (author)

  11. 'Test Driving' a Financing Instrument for Climate Adaptation

    NARCIS (Netherlands)

    Root, Liz; Krabben, van der Erwin; Spit, Tejo

    2016-01-01

    Urban physical public infrastructure is a frontline defense mechanism to manage and mitigate climate-related impacts. Market instruments are often cited as possible means to spread risk and reduce financial burdens on the public sector. The authors argue that existing research tends to focus on the

  12. The Mechanics of Peak-Ring Impact Crater Formation from the IODP-ICDP Expedition 364

    Science.gov (United States)

    Melosh, H.; Collins, G. S.; Morgan, J. V.; Gulick, S. P. S.

    2017-12-01

    The Chicxulub impact crater is one of very few peak-ring impact craters on Earth. While small (less than 3 km on Earth) impact craters are typically bowl-shaped, larger craters exhibit central peaks, which in still larger (more than about 100 km on Earth) craters expand into mountainous rings with diameters close to half that of the crater rim. The origin of these peak rings has been contentious: Such craters are far too large to create in laboratory experiments and remote sensing of extraterrestrial examples has not clarified the mechanics of their formation. Two principal models of peak ring formation are currently in vogue, the "nested crater" model, in which the peak ring originates at shallow depths in the target, and the "dynamic collapse" model in which the peak ring is uplifted at the base of a collapsing, over-steepened central peak and its rocks originate at mid-crustal depths. IODP-ICDP Expedition 364 sought to elucidate, among other important goals, the mechanics of peak ring formation in the young (66 Myr), fresh, but completely buried Chicxulub impact crater. The cores from this borehole now show unambiguously that the rocks in the Chicxulub peak ring originated at mid-crustal depths, apparently ruling out the nested crater model. These rocks were shocked to pressures on the order of 10-35 GPa and were so shattered that their densities and seismic velocities now resemble those of sedimentary rocks. The morphology of the final crater, its structure as revealed in previous seismic imaging, and the results from the cores are completely consistent with modern numerical models of impact crater excavation and collapse that incorporate a model for post-impact weakening. Subsequent to the opening of a ca. 100 km diameter and 30 km deep transient crater, this enormous hole in the crust collapsed over a period of about 10 minutes. Collapse was enabled by movement of the underlying rocks, which briefly behaved in the manner of a high-viscosity fluid, a brittle

  13. Failure mechanism of coated biomaterials under high impact-sliding contact stresses

    Science.gov (United States)

    Chen, Ying

    This study uses a newly developed testing method--- inclined cyclic impact-sliding test to investigate the failure behaviors of different types of biomaterials, (SS316L, Ti6Al4V and CoCr) coated by different coatings (TiN, DLC and PEO), under extremely high dynamic contact stress conditions. This test method can simulate the combined impact and sliding/rolling loading conditions, which is very practical in many aspects of commercial usages. During the tests, fatigue cracking, chipping, peeling and material transferring were observed in damaged area. This research is mainly focused on the failure behaviors of load-bearing materials which cyclic impacting and sliding are always involved. This purpose was accomplished in the three stages: First, impact-sliding test was carried out on TiN coated unhardened M2. It was found that soft substrate can cause early failure of coating due to the considerable plastic deformation in the substrate. In this case, stronger substrate is required to support coating better when tested under high contact stresses. Second, PEO coated Ti-6Al-4V was tested under pure sliding and impact-sliding wear conditions. PEO coating was found not strong enough to afford the high contact pressure under cyclic impact-sliding wear test due to its porous surface structure. However, the wear performance of PEO coating was enhanced due to the sub-stoichiometric oxide. To sum up, for load-bearing biomedical implants involved in high impacting movement, PEO coating may not be a promising surface protection. Third, the dense, smooth PVD/CVD bio-inert coatings were reconsidered. DLC and TiN coatings, combined by different substrates together with different interface materials were tested under the cyclic impact-sliding test using a set of proper loading. The results show that to choose a proper combination of coating, interface and substrate based on their mechanical properties is of great importance under the test condition. Hard substrates provide support

  14. Instrumental analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Jae; Seo, Seong Gyu

    1995-03-15

    This textbook deals with instrumental analysis, which consists of nine chapters. It has Introduction of analysis chemistry, the process of analysis and types and form of the analysis, Electrochemistry on basic theory, potentiometry and conductometry, electromagnetic radiant rays and optical components on introduction and application, Ultraviolet rays and Visible spectrophotometry, Atomic absorption spectrophotometry on introduction, flame emission spectrometry and plasma emission spectrometry. The others like infrared spectrophotometry, X-rays spectrophotometry and mass spectrometry, chromatography and the other instrumental analysis like radiochemistry.

  15. Instrumental analysis

    International Nuclear Information System (INIS)

    Kim, Seung Jae; Seo, Seong Gyu

    1995-03-01

    This textbook deals with instrumental analysis, which consists of nine chapters. It has Introduction of analysis chemistry, the process of analysis and types and form of the analysis, Electrochemistry on basic theory, potentiometry and conductometry, electromagnetic radiant rays and optical components on introduction and application, Ultraviolet rays and Visible spectrophotometry, Atomic absorption spectrophotometry on introduction, flame emission spectrometry and plasma emission spectrometry. The others like infrared spectrophotometry, X-rays spectrophotometry and mass spectrometry, chromatography and the other instrumental analysis like radiochemistry.

  16. LOFT instrumentation

    International Nuclear Information System (INIS)

    Bixby, W.W.

    1979-01-01

    A description of instrumentation used in the Loss-of-Fluid Test (LOFT) large break Loss-of-Coolant Experiments is presented. Emphasis is placed on hydraulic and thermal measurements in the primary system piping and components, reactor vessel, and pressure suppression system. In addition, instrumentation which is being considered for measurement of phenomena during future small break testing is discussed. (orig.) 891 HP/orig. 892 BRE [de

  17. Astrogliosis has Different Dynamics after Cell Transplantation and Mechanical Impact in the Rodent Model of Parkinson‘s Disease

    Directory of Open Access Journals (Sweden)

    Nikola Tomov

    2018-03-01

    Full Text Available Background: Transplantation of fetal mesencephalic tissue is a well-established concept for functional reinnervation of the dopamine-depleted rat striatum. However, there is no extensive description of the glial response of the host brain following this procedure. Aims: The present study aimed to quantitatively and qualitatively analyse astrogliosis surrounding intrastriatal grafts and compare it to the reaction to mechanical injury with the transplantation instrument only. Study Design: Animal experimentation. Methods: The standard 6-hydroxydopamine-induced unilateral model of Parkinson's disease was used. The experimental animals received transplantation of a single-cell suspension of E14 ventral mesencephalic tissue. Control animals (sham-transplanted were subjected to injury by the transplantation cannula, without injection of a cell suspension. Histological analyses were carried out 7 and 28 days following the procedure by immunohistochemistry assays for tyrosine hydroxylase and glial fibrillary acidic protein. To evaluate astrogliosis, the cell density and immunopositive area were measured in distinct zones within and surrounding the grafts or the cannula tract. Results: Statistical analysis revealed that astrogliosis in the grafted striatum increased from day 7 to day 28, as shown by a significant change in both cell density and the immunopositive area. The cell density increased from 816.7±370.6 to 1403±272.1 cells/mm2 (p<0.0001 аnd from 523±245.9 to 1164±304.8 cells/mm2 (p<0.0001 in the two zones in the graft core, and from 1151±218.6 to 1485±210.6 cells/mm2 (p<0.05 for the zone in the striatum immediately adjacent to the graft. The glial fibrillary acidic protein-expressing area increased from 0.3109±0.1843 to 0.7949±0.1910 (p<0.0001 and from 0.1449±0.1240 to 0.702±0.2558 (p<0.0001 for the same zones in the graft core, and from 0.5277±0.1502 to 0.6969±0.1223 (p<0.0001 for the same area adjacent to the graft zone. However

  18. Astrogliosis has Different Dynamics after Cell Transplantation and Mechanical Impact in the Rodent Model of Parkinson‘s Disease

    Directory of Open Access Journals (Sweden)

    Nikola Tomov

    2018-03-01

    Full Text Available Background: Transplantation of fetal mesencephalic tissue is a well-established concept for functional reinnervation of the dopamine-depleted rat striatum. However, there is no extensive description of the glial response of the host brain following this procedure. Aims: The present study aimed to quantitatively and qualitatively analyse astrogliosis surrounding intrastriatal grafts and compare it to the reaction to mechanical injury with the transplantation instrument only. Study Design: Animal experimentation. Methods: The standard 6-hydroxydopamine-induced unilateral model of Parkinson’s disease was used. The experimental animals received transplantation of a single-cell suspension of E14 ventral mesencephalic tissue. Control animals (sham-transplanted were subjected to injury by the transplantation cannula, without injection of a cell suspension. Histological analyses were carried out 7 and 28 days following the procedure by immunohistochemistry assays for tyrosine hydroxylase and glial fibrillary acidic protein. To evaluate astrogliosis, the cell density and immunopositive area were measured in distinct zones within and surrounding the grafts or the cannula tract. Results: Statistical analysis revealed that astrogliosis in the grafted striatum increased from day 7 to day 28, as shown by a significant change in both cell density and the immunopositive area. The cell density increased from 816.7±370.6 to 1403±272.1 cells/mm2 (p<0.0001 аnd from 523±245.9 to 1164±304.8 cells/mm2 (p<0.0001 in the two zones in the graft core, and from 1151±218.6 to 1485±210.6 cells/mm2 (p<0.05 for the zone in the striatum immediately adjacent to the graft. The glial fibrillary acidic protein-expressing area increased from 0.3109±0.1843 to 0.7949±0.1910 (p<0.0001 and from 0.1449±0.1240 to 0.702±0.2558 (p<0.0001 for the same zones in the graft core, and from 0.5277±0.1502 to 0.6969±0.1223 (p<0.0001 for the same area adjacent to the graft zone. However

  19. A study of thermo-mechanical stress and its impact on through-silicon vias

    International Nuclear Information System (INIS)

    Ranganathan, N; Balasubramanian, N; Prasad, K; Pey, K L

    2008-01-01

    The BOSCH etch process, which is commonly used in microelectromechanical system fabrication, has been extensively investigated in this work for implementation in through-silicon via (TSV) technology for 3D-microsystems packaging. The present work focuses on thermo-mechanical stresses caused by thermal loading due to post-TSV processes and their impact on the electrical performance of through-silicon copper interconnects. A test vehicle with deep silicon copper-plated comb structure was designed to study and evaluate different deep silicon via etch processes and its effect on the electrical leakage characteristics under various electrical and thermal stress conditions. It has been shown that the leakage current between the comb interconnect structures increases with an increase in sidewall roughness and that it can be significantly lowered by smoothening the sidewalls. It was also shown that by tailoring a non-BOSCH etch process with the normal BOSCH process, a similar leakage current reduction can be achieved. It was also shown through thermo-mechanical simulation studies that there is a clear correlation between high leakage current behavior due to non-uniform Ta barrier deposition over the rough sidewalls and the thermo-mechanical stress induced by post-TSV processes

  20. Evolution of mechanical properties of silicate glasses: Impact of the chemical composition and effects of irradiation

    International Nuclear Information System (INIS)

    Barlet, Marina

    2014-01-01

    This thesis examines: (1) how the chemical composition changes the hardness, toughness, and stress corrosion cracking behavior in model pristine and (2) how external irradiation impact these properties. It is to be incorporated in the context of the storage of nuclear waste in borosilicate glass matrix, the structural integrity of which should be assessed. Eight simplified borosilicate glasses made of 3 oxides with modulated proportions (SiO 2 -B 2 O 3 -Na 2 O (SBN) have been selected and their hardness, toughness, and stress corrosion cracking behavior have been characterized prior and after irradiation. The comparative study of the non-irradiated SBN glasses provides the role played by the chemical composition. The sodium content is found to be the key parameter: As it increases, the glass plasticity increases, leading to changes in the mechanical response to strain. Hardness (Hv) and toughness (Kc) decrease since the flow under indenter increases. The analysis of the stress corrosion behavior evidences a clear shift of the SCC curves linked also to the glass plasticity. Four of the 8 simplified SBN glass systems highlight the influence of electron, light and heavy ions irradiations on the mechanical properties. Once again, the sodium content is a key parameter. It is found to inhibit the glass modification: Glasses with high sodium content are more stable. Ions irradiations highlight the predominant role of nuclear interaction in changing the glass properties. Finally, electronic interaction induced by helium and electron irradiation does not lead to the same structural/mechanical glasses variations. (author) [fr

  1. The Impact of opium consumption on blood glucose, serum lipids and blood pressure, and related mechanisms

    Directory of Open Access Journals (Sweden)

    Hamid Najafipour

    2016-10-01

    Full Text Available AbstractAim: Substance abuse has become a universal crisisin our modern age. Among illegal substances, opium and its derivatives have been ranked second in terms of usage after cannabis in the world. In many Asian regions, the use of opium enjoys a high social acceptance; hence, some common people and even medical practitioners believe that opium lowers blood glucose and pressure and treat dyslipidemia. How much this belief is scientifically justified? Method: The results of available studies on both humans and animals searched in different search engines up to mid-2016 were integrated (77 articles. Upon the findings we try to offer a more transparent picture of the effects of opium on the mentioned factors along with the probable underlying mechanisms of its action. Results: Taken together, a variety of evidences suggest that the consumption of opium has no scientific justification for amendment of these biochemical variables. The mechanisms proposed so far for the action of opium in the three above disorders are summarized at the end of the article. Short term effects seems to be mostly mediated through central nervous system (neural and hormonal mechanisms, but long term effects are often due to the structural and functional alterations in some body organs. Conclusion: Although opium may temporarily reduce blood pressure, but it increases blood glucose and most of blood lipids. Moreover its long term use has negative impacts and thus it aggravates diabetes, dyslipidemia and hypertension. Accordingly, it is necessary to inform societies about the potential disadvantages of unauthorized opium consumption.

  2. Mineralogical Plasticity Acts as a Compensatory Mechanism to the Impacts of Ocean Acidification.

    Science.gov (United States)

    Leung, Jonathan Y S; Russell, Bayden D; Connell, Sean D

    2017-03-07

    Calcifying organisms are considered particularly susceptible to the future impacts of ocean acidification (OA), but recent evidence suggests that they may be able to maintain calcification and overall fitness. The underlying mechanism remains unclear but may be attributed to mineralogical plasticity, which modifies the energetic cost of calcification. To test the hypothesis that mineralogical plasticity enables the maintenance of shell growth and functionality under OA conditions, we assessed the biological performance of a gastropod (respiration rate, feeding rate, somatic growth, and shell growth of Austrocochlea constricta) and analyzed its shell mechanical and geochemical properties (shell hardness, elastic modulus, amorphous calcium carbonate, calcite to aragonite ratio, and magnesium to calcium ratio). Despite minor metabolic depression and no increase in feeding rate, shell growth was faster under OA conditions, probably due to increased precipitation of calcite and trade-offs against inner shell density. In addition, the resulting shell was functionally suitable for increasingly "corrosive" oceans, i.e., harder and less soluble shells. We conclude that mineralogical plasticity may act as a compensatory mechanism to maintain overall performance of calcifying organisms under OA conditions and could be a cornerstone of calcifying organisms to acclimate to and maintain their ecological functions in acidifying oceans.

  3. Influence of mechanical, thermal and radiation impacts on structure and properties of poly-L-lactide

    International Nuclear Information System (INIS)

    Marchenko, L.A.; Butovskaya, G.V.; Tapal'skij, D.V.; Krul', L.P.

    2014-01-01

    Poly-L-lactide both in the form of granules and plates obtained by injection molding has been revealed using differential scanning calorimetry and dynamic mechanical (relaxation) spectroscopy to be in the amorphous-crystalline phase state, the crystal phase being in two forms which differ in a degree of ordering. The radiation dose increase has been shown to facilitate the transition of disordered crystal phase into ordered one. Two types of amorphous phase of poly-L-lactide, mobile and rigid, differing in temperatures of the relaxation transitions have been revealed. A symbate change of the mobile amorphous phase content and antibate change of that of the rigid one with the radiation dose has been found. High strength properties and low deformability of the polymer under mechanical stretching at room temperature as well as the resistance to mechanical impact at a temperature of liquid nitrogen has been pointed out. It has been shown that chain degradation of the poly-L-lactide under conditions of vapor sterilization and radiation are negligible, so these methods may be used for disinfecting of medical devices based on this polymer. (authors)

  4. The Impact of Opium Consumption on Blood Glucose, Serum Lipids and Blood Pressure, and Related Mechanisms

    Science.gov (United States)

    Najafipour, Hamid; Beik, Ahmad

    2016-01-01

    Aim: Substance abuse has become a universal crisis in our modern age. Among illegal substances, opium and its derivatives have been ranked second in terms of usage after cannabis in the world. In many Asian regions, the use of opium enjoys a high social acceptance; hence, some common people and even medical practitioners believe that opium lowers blood glucose and pressure and treat dyslipidemia. How much this belief is scientifically justified? Method: The results of available studies on both humans and animals searched in different search engines up to mid-2016 were integrated (78 articles). Upon the findings we try to offer a more transparent picture of the effects of opium on the mentioned factors along with the probable underlying mechanisms of its action. Results: Taken together, a variety of evidences suggest that the consumption of opium has no scientific justification for amendment of these biochemical variables. The mechanisms proposed so far for the action of opium in the three above disorders are summarized at the end of the article. Short term effects seems to be mostly mediated through central nervous system (neural and hormonal mechanisms), but long term effects are often due to the structural and functional alterations in some body organs. Conclusion: Although opium may temporarily reduce blood pressure, but it increases blood glucose and most of blood lipids. Moreover its long term use has negative impacts and thus it aggravates diabetes, dyslipidemia and hypertension. Accordingly, it is necessary to inform societies about the potential disadvantages of unauthorized opium consumption. PMID:27790151

  5. The Impact of Opium Consumption on Blood Glucose, Serum Lipids and Blood Pressure, and Related Mechanisms.

    Science.gov (United States)

    Najafipour, Hamid; Beik, Ahmad

    2016-01-01

    Aim: Substance abuse has become a universal crisis in our modern age. Among illegal substances, opium and its derivatives have been ranked second in terms of usage after cannabis in the world. In many Asian regions, the use of opium enjoys a high social acceptance; hence, some common people and even medical practitioners believe that opium lowers blood glucose and pressure and treat dyslipidemia. How much this belief is scientifically justified? Method: The results of available studies on both humans and animals searched in different search engines up to mid-2016 were integrated (78 articles). Upon the findings we try to offer a more transparent picture of the effects of opium on the mentioned factors along with the probable underlying mechanisms of its action. Results: Taken together, a variety of evidences suggest that the consumption of opium has no scientific justification for amendment of these biochemical variables. The mechanisms proposed so far for the action of opium in the three above disorders are summarized at the end of the article. Short term effects seems to be mostly mediated through central nervous system (neural and hormonal mechanisms), but long term effects are often due to the structural and functional alterations in some body organs. Conclusion: Although opium may temporarily reduce blood pressure, but it increases blood glucose and most of blood lipids. Moreover its long term use has negative impacts and thus it aggravates diabetes, dyslipidemia and hypertension. Accordingly, it is necessary to inform societies about the potential disadvantages of unauthorized opium consumption.

  6. Impact of Prosthesis-Patient Mismatch on Long-term Functional Capacity After Mechanical Aortic Valve Replacement

    NARCIS (Netherlands)

    Petit-Eisenmann, H.; Epailly, E.; Velten, M.; Radojevic, J.; Eisenmann, B.; Kremer, H.; Kindo, M.

    2016-01-01

    BACKGROUND: The impact of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) for aortic stenosis on exercise capacity remains controversial. The aim of this study was to analyze the long-term impact of PPM after mechanical AVR on maximal oxygen uptake (VO2max). METHODS: The study

  7. Using Financial Instruments to Transfer the Information Security Risks

    OpenAIRE

    Pankaj Pandey; Einar Snekkenes

    2016-01-01

    For many individuals and organizations, cyber-insurance is the most practical and only way of handling a major financial impact of an information security event. However, the cyber-insurance market suffers from the problem of information asymmetry, lack of product diversity, illiquidity, high transaction cost, and so on. On the other hand, in theory, capital market-based financial instruments can provide a risk transfer mechanism with the ability to absorb the adverse impact of an information...

  8. Mechanical property characterization and impact resistance of selected graphite/PEEK composite materials

    Science.gov (United States)

    Baker, Donald J.

    1994-01-01

    To use graphite polyetheretherketone (PEEK) material on highly curved surfaces requires that the material be drapable and easily conformable to the surface. This paper presents the mechanical property characterization and impact resistance results for laminates made from two types of graphite/PEEK materials that will conform to a curved surface. These laminates were made from two different material forms. These forms are: (1) a fabric where each yarn is a co-mingled Celion G30-500 3K graphite fiber and PEEK thermoplastic fiber; and (2) an interleaved material of Celion G30-500 3K graphite fabric interleaved with PEEK thermoplastic film. The experimental results from the fabric laminates are compared with results for laminates made from AS4/PEEK unidirectional tape. The results indicate that the tension and compression moduli for quasi-isotropic and orthotropic laminates made from fabric materials are at least 79 percent of the modulus of equivalent laminates made from tape material. The strength of fabric material laminates is at least 80 percent of laminates made from tape material. The evaluation of fabric material for shear stiffness indicates that a tape material laminate could be replaced by a fabric material laminate and still maintain 89 percent of the shear stiffness of the tape material laminate. The notched quasi-isotropic compression panel failure strength is 42 to 46 percent of the unnotched quasi-isotropic laminate strength. Damage area after impact with 20 ft-lbs of impact energy is larger for the co-mingled panels than for the interleaved panels. The inerleaved panels have less damage than panels made from tape material. Residual compression strength of quasi-isotropic panels after impact of 20 ft-lbs of energy varies between 33 percent of the undamaged quasi-isotropic material strength for the tape material and 38 percent of the undamaged quasi-isotropic material strength for the co-mingled fabric material.

  9. Pulpar temperature changes during mechanical reduction of equine cheek teeth: comparison of different motorised dental instruments, duration of treatments and use of water cooling.

    Science.gov (United States)

    O'Leary, J M; Barnett, T P; Parkin, T D H; Dixon, P M; Barakzai, S Z

    2013-05-01

    Although equine motorised dental instruments are widely used, there is limited information on their thermal effect on teeth. The recently described variation in subocclusal secondary dentine depth overlying individual pulp horns may affect heat transmission to the underlying pulps. This study compared the effect of 3 different equine motorised dental instruments on the pulpar temperature of equine cheek teeth with and without the use of water cooling. It also evaluated the effect of subocclusal secondary dentine thickness on pulpar temperature changes. A thermocouple probe was inserted into the pulp horns of 188 transversely sectioned maxillary cheek teeth with its tip lying subocclusally. Pulpar temperature changes were recorded during and following the continuous use of 3 different equine motorised dental instruments (A, B and C) for sequential time periods, with and without the use of water cooling. Using motorised dental instrument B compared with either A or C increased the likelihood that the critical temperature was reached in pulps by 8.6 times. Compared with rasping for 30 s, rasping for 45, 60 and 90 s increased the likelihood that the critical temperature would be reached in pulps by 7.3, 8.9 and 24.7 times, respectively. Thicker subocclusal secondary dentine (odds ratio [OR] = 0.75/mm) and water cooling (OR = 0.14) were both protective against the likelihood of the pulp reaching the critical temperature. Prolonged rasping with motorised dental instruments increased the likelihood that a pulp would be heated above the critical temperature. Increased dentinal thickness and water cooling had protective roles in reducing pulpar heating. Motorised dental instruments have the potential to seriously damage equine pulp if used inappropriately. Higher speed motorised dental instruments should be used for less time and teeth should be water cooled during or immediately after instrument use to reduce the risk of thermal pulpar damage. © 2012 EVJ Ltd.

  10. High Strain Rate Deformation Mechanisms of Body Centered Cubic Material Subjected to Impact Loading

    Science.gov (United States)

    Visser, William

    Low carbon steel is the most common grade of structural steel used; it has carbon content of 0.05% to 0.25% and very low content of alloying elements. It is produced in great quantities and provides material properties that are acceptable for many engineering applications, particularly in the construction industry in which low carbon steel is widely used as the strengthening phase in civil structures. The overall goal of this dissertation was to investigate the deformation response of A572 grade 50 steel when subjected to impact loading. This steel has a 0.23% by weight carbon content and has less than 2% additional alloying elements. The deformation mechanisms of this steel under shock loading conditions include both dislocation motion and twin formation. The goal of this work was achieved by performing experimental, analytical and numerical research in three integrated tasks. The first is to determine the relationship between the evolution of deformation twins and the impact pressure. Secondly, a stress criterion for twin nucleation during high strain rate loading was developed which can account for the strain history or initial dislocation density. Lastly, a method was applied for separating the effects of dislocations and twins generated by shock loading in order to determine their role in controlling the flow stress of the material. In this regard, the contents of this work have been categorically organized. First, the active mechanisms in body centered cubic (BCC) low carbon steel during shock loading have been determined as being a composed of the competing mechanisms of dislocations and deformation twins. This has been determined through a series of shock loading tests of the as-received steel. The shock loading tests were done by plate impact experiments at several impact pressures ranging from 2GPa up to 13GPa using a single stage light gas gun. A relationship between twin volume fraction and impact pressure was determined and an analytical model was

  11. The Impact of a Mechanical Press on the Accuracy of Products and the Reliability of Tools in Cold Forging

    DEFF Research Database (Denmark)

    Krusic, V.; Arentoft, Mogens; Rodic, T.

    2005-01-01

    Cold extrusion is an economic production process for the production of elements of complex forms and accurate dimensions. The first part of the article is about the impact that mechanical press has on the accuracy of products and reliability of tools. There is a description of the mechanical pres...

  12. Instrumental Capital

    Directory of Open Access Journals (Sweden)

    Gabriel Valerio

    2007-07-01

    Full Text Available During the history of human kind, since our first ancestors, tools have represented a mean to reach objectives which might otherwise seemed impossibles. In the called New Economy, where tangibles assets appear to be losing the role as the core element to produce value versus knowledge, tools have kept aside man in his dairy work. In this article, the author's objective is to describe, in a simple manner, the importance of managing the organization's group of tools or instruments (Instrumental Capital. The characteristic conditions of this New Economy, the way Knowledge Management deals with these new conditions and the sub-processes that provide support to the management of Instrumental Capital are described.

  13. Development of a Spring-Loaded Impact Device to Deliver Injurious Mechanical Impacts to the Articular Cartilage Surface

    Science.gov (United States)

    Alexander, Peter G.; Song, Yingjie; Taboas, Juan M.; Chen, Faye H.; Melvin, Gary M.; Manner, Paul A.

    2013-01-01

    Objective: Traumatic impacts on the articular joint surface in vitro are known to lead to degeneration of the cartilage. The main objective of this study was to develop a spring-loaded impact device that can be used to deliver traumatic impacts of consistent magnitude and rate and to find whether impacts cause catabolic activities in articular cartilage consistent with other previously reported impact models and correlated with the development of osteoarthritic lesions. In developing the spring-loaded impactor, the operating hypothesis is that a single supraphysiologic impact to articular cartilage in vitro can affect cartilage integrity, cell viability, sulfated glycosaminoglycan and inflammatory mediator release in a dose-dependent manner. Design: Impacts of increasing force are delivered to adult bovine articular cartilage explants in confined compression. Impact parameters are correlated with tissue damage, cell viability, matrix and inflammatory mediator release, and gene expression 24 hours postimpact. Results: Nitric oxide release is first detected after 7.7 MPa impacts, whereas cell death, glycosaminoglycan release, and prostaglandin E2 release are first detected at 17 MPa. Catabolic markers increase linearly to maximal levels after ≥36 MPa impacts. Conclusions: A single supraphysiologic impact negatively affects cartilage integrity, cell viability, and GAG release in a dose-dependent manner. Our findings showed that 7 to 17 MPa impacts can induce cell death and catabolism without compromising the articular surface, whereas a 17 MPa impact is sufficient to induce increases in most common catabolic markers of osteoarthritic degeneration. PMID:26069650

  14. Innovative instrumentation

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    At this year's particle physics conference at Brighton, a parallel session was given over to instrumentation and detector development. While this work is vital to the health of research and its continued progress, its share of prime international conference time is limited. Instrumentation can be innovative three times — first when a new idea is outlined, secondly when it is shown to be feasible, and finally when it becomes productive in a real experiment, amassing useful data rather than operational experience. Hyams' examples showed that it can take a long time for a new idea to filter through these successive stages, if it ever makes it at all

  15. Innovative instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1983-11-15

    At this year's particle physics conference at Brighton, a parallel session was given over to instrumentation and detector development. While this work is vital to the health of research and its continued progress, its share of prime international conference time is limited. Instrumentation can be innovative three times — first when a new idea is outlined, secondly when it is shown to be feasible, and finally when it becomes productive in a real experiment, amassing useful data rather than operational experience. Hyams' examples showed that it can take a long time for a new idea to filter through these successive stages, if it ever makes it at all.

  16. Instrumental aspects

    Directory of Open Access Journals (Sweden)

    Qureshi Navid

    2017-01-01

    Full Text Available Every neutron scattering experiment requires the choice of a suited neutron diffractometer (or spectrometer in the case of inelastic scattering with its optimal configuration in order to accomplish the experimental tasks in the most successful way. Most generally, the compromise between the incident neutron flux and the instrumental resolution has to be considered, which is depending on a number of optical devices which are positioned in the neutron beam path. In this chapter the basic instrumental principles of neutron diffraction will be explained. Examples of different types of experiments and their respective expectable results will be shown. Furthermore, the production and use of polarized neutrons will be stressed.

  17. Mechanical Properties of the Surface Material of Comet 67P/Churyumov-Gerasimenko Measured By the Casse Instrument Onboard the Philae Lander

    Science.gov (United States)

    Knapmeyer, M.; Fischer, H. H.; Seidensticker, K. J.; Arnold, W.; Faber, C.; Möhlmann, D.; Thiel, K.

    2014-12-01

    Satellite remote sensing of ocean color is a critical tool for assessing the productivity of marine ecosystems and monitoring changes resulting from climatic or environmental influences. Yet water-leaving radiance comprises less than 10% of the signal measured from space, making correction for absorption and scattering by the intervening atmosphere imperative. Traditional ocean color retrieval algorithms utilize a standard set of aerosol models and the assumption of negligible water-leaving radiance in the near-infrared. Modern improvements have been developed to handle absorbing aerosols such as urban particulates in coastal areas and transported desert dust over the open ocean, where ocean fertilization can impact biological productivity at the base of the marine food chain. Even so, imperfect knowledge of the absorbing aerosol optical properties or their height distribution results in well-documented sources of error. In the UV, the problem of UV-enhanced absorption and nonsphericity of certain aerosol types are amplified due to the increased Rayleigh and aerosol optical depth, especially at off-nadir view angles. Multi-angle spectro-polarimetric measurements have been advocated as an additional tool to better understand and retrieve the aerosol properties needed for atmospheric correction for ocean color retrievals. The central concern of the work to be described is the assessment of the effects of absorbing aerosol properties on water leaving radiance measurement uncertainty by neglecting UV-enhanced absorption of carbonaceous particles and by not accounting for dust nonsphericity. In addition, we evaluate the polarimetric sensitivity of absorbing aerosol properties in light of measurement uncertainties achievable for the next generation of multi-angle polarimetric imaging instruments, and demonstrate advantages and disadvantages of wavelength selection in the UV/VNIR range. The phase matrices for the spherical smoke particles were calculated using a standard

  18. How the Quantity of Agricultural Mechanics Training Received at the Secondary Level Impact Teacher Perceived Importance of Agricultural Mechanics Skills

    Science.gov (United States)

    Rasty, John; Anderson, Ryan G.; Paulsen, Thomas H.

    2017-01-01

    Preservice teacher candidates in agricultural education have expressed concerns with teaching agricultural mechanics content yet the number of required courses in agricultural mechanics has dwindled. To determine the root of current teachers' perceptions, it is important to look at the developmental experiences that have led to those perceptions.…

  19. Application of Instrumented Charpy Method in Characterisation of Materials

    Directory of Open Access Journals (Sweden)

    Željko Alar

    2015-07-01

    Full Text Available Testing of absorbed impact energy according to the Charpy method is carried out to determine the behaviour of a material under the impact load. Instrumented Charpy method allows getting the force displacement curve through the entire test, That curve can be related to force-displacement curve which is obtained by the static tensile test. The purpose of this study was to compare the results of forces obtained by the static tensile test with the forces obtained by the instrumented Charpy method. Experimental part of the work contains testing of the mechanical properties of S275J0 steel by the static tensile test and Impact test on instrumented Charpy pendulum.

  20. Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Eric [Building Science Corporation, Westford, MA (United States)

    2014-01-01

    Optimizing whole house mechanical ventilation as part of the Building Ameerica program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this report is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

  1. Impact of the fouling mechanism on enzymatic depolymerization of xylan in different configurations of membrane reactors

    DEFF Research Database (Denmark)

    Mohd Sueb, Mohd Shafiq Bin; Luo, Jianquan; Meyer, Anne S.

    2017-01-01

    In order to maximize enzymatic xylan depolymerization while simultaneously purifying the resulting monosaccharide (xylose), different ultrafiltration (UF) membrane reactor configurations were evaluated. Initial results showed that the two hydrolytic enzymes required for complete depolymerization...... which hindered enzymatic attack in addition to fouling. Reaction with both enzymes followed by UF was found to be the optimal configuration, providing at least 40% higher xylan hydrolysis than the cascade configuration (involving sequential reaction with each of the enzymes separately......) and the simultaneous reaction-filtration with both enzymes, respectively. This study thus confirmed that the reactor configuration has a crucial impact on the performance of both the reaction and the separation process of xylose during enzymatic xylan degradation, and that the type of fouling mechanism varies...

  2. Effect of steel structure and defects on reliability of parts of impact mechanisms

    Science.gov (United States)

    Popelyukh, AI; Repin, AA; Alekseev, SE

    2018-03-01

    The paper discusses selection of materials suitable for manufacturing critical parts of impact mechanisms. It is shown that in order to extend life of parts exposed to high dynamic loading, it is expedient to use medium- and high-carbon alloy-treated steels featuring low impurity with nonmetallic inclusions and high hardening characteristics. Application of thermally untreated parts is undesirable as steel having ferrite–pearlite structure possesses low fatigue strength. Aimed to ensure high reliability of parts with a hardness of 42–55 HRC, steel should be reinforced by thermal treatement with the formation of multicomponent martensite–bainite structure. High-quality production should include defectoscopy and incoming material control.

  3. Impact of Mechanical down Tilt and Height on the Pilot Coverage of UMTS Networks

    Directory of Open Access Journals (Sweden)

    N. Faruk

    2012-06-01

    Full Text Available The task of planning a network can be very challenging as it involves many careful studies with a lot of considerations and, at times, trial and error. In this paper, the impacts of antenna mechanical down tilt and antenna height on UMTS network performance are studied. First, we used ASSET3G simulation software to design 3G pilot coverage. Optimization techniques were deployed to study the performance of the network. Simulation results show about 2.6% increase in the coverage area when the antenna height was increased from 15 m to 25 m at the same tilt angle of 0 ° The coverage drops by 24% when transiting from 0° to 6° tilt angle was made for 15 m height antenna. The results also indicated that, pilot pollution could be reduced by choosing optimum down tilt angle.

  4. Mechanisms and impact of genetic recombination in the evolution of Streptococcus pneumoniae.

    Science.gov (United States)

    Chaguza, Chrispin; Cornick, Jennifer E; Everett, Dean B

    2015-01-01

    Streptococcus pneumoniae (the pneumococcus) is a highly recombinogenic bacterium responsible for a high burden of human disease globally. Genetic recombination, a process in which exogenous DNA is acquired and incorporated into its genome, is a key evolutionary mechanism employed by the pneumococcus to rapidly adapt to selective pressures. The rate at which the pneumococcus acquires genetic variation through recombination is much higher than the rate at which the organism acquires variation through spontaneous mutations. This higher rate of variation allows the pneumococcus to circumvent the host innate and adaptive immune responses, escape clinical interventions, including antibiotic therapy and vaccine introduction. The rapid influx of whole genome sequence (WGS) data and the advent of novel analysis methods and powerful computational tools for population genetics and evolution studies has transformed our understanding of how genetic recombination drives pneumococcal adaptation and evolution. Here we discuss how genetic recombination has impacted upon the evolution of the pneumococcus.

  5. Impact of whole-body rehabilitation in patients receiving chronic mechanical ventilation.

    Science.gov (United States)

    Martin, Ubaldo J; Hincapie, Luis; Nimchuk, Mark; Gaughan, John; Criner, Gerard J

    2005-10-01

    To evaluate the prevalence and magnitude of weakness in patients receiving chronic mechanical ventilation and the impact of providing aggressive whole-body rehabilitation on conventional weaning variables, muscle strength, and overall functional status. Retrospective analysis of 49 consecutive patients. Multidisciplinary ventilatory rehabilitation unit in an academic medical center. Forty-nine consecutive chronic ventilator-dependent patients referred to a tertiary care hospital ventilator rehabilitation unit. None. Patients were 58 +/- 7 yrs old with multiple etiologies for respiratory failure. On admission, all patients were bedridden and had severe weakness of upper and lower extremities measured by a 5-point muscle strength score and a 7-point Functional Independence Measurement. Postrehabilitation, patients had increases in upper and lower extremity strength (p respiratory muscle training with an improvement in strength, weaning outcome, and functional status. Whole-body rehabilitation should be considered a significant component of their therapy.

  6. The impact of rate of weight loss on body composition and compensatory mechanisms during weight reduction

    DEFF Research Database (Denmark)

    Coutinho, Sílvia Ribeiro; With, Emilie; Rehfeld, Jens F

    2018-01-01

    BACKGROUND & AIMS: Rapid weight loss (WL) has been associated with a larger loss of fat free mass and a disproportional reduction in resting metabolic rate (RMR), but the evidence is inconclusive. We aimed to evaluate the impact of WL rate on body composition and compensatory mechanisms activated...... with WL (reduced RMR, increased exercise efficiency (ExEff) and appetite), both during negative and neutral energy balance (EB). METHODS: Thirty-five participants with obesity were randomized to lose a similar weight rapidly (4 weeks) or gradually (8 weeks), and afterwards to maintain it (4 weeks). Body...... weight and composition, RMR, ExEff (10, 25 and 50 W), appetite feelings and appetite-regulating hormones (active ghrelin, cholecystokinin, total peptide YY (PYY), active glucagon-like peptide-1 and insulin), in fasting and every 30 min up to 2.5 h, were measured at baseline and after each phase. RESULTS...

  7. Causes and Mechanisms of Intrauterine Hypoxia and Its Impact on the Fetal Cardiovascular System: A Review

    Directory of Open Access Journals (Sweden)

    Damian Hutter

    2010-01-01

    Full Text Available Until today the role of oxygen in the development of the fetus remains controversially discussed. It is still believed that lack of oxygen in utero might be responsible for some of the known congenital cardiovascular malformations. Over the last two decades detailed research has given us new insights and a better understanding of embryogenesis and fetal growth. But most importantly it has repeatedly demonstrated that oxygen only plays a minor role in the early intrauterine development. After organogenesis has taken place hypoxia becomes more important during the second and third trimester of pregnancy when fetal growth occurs. This review will briefly adress causes and mechanisms leading to intrauterine hypoxia and their impact on the fetal cardiovascular system.

  8. Surgical Instrument

    NARCIS (Netherlands)

    Dankelman, J.; Horeman, T.

    2009-01-01

    The present invention relates to a surgical instrument for minimall-invasive surgery, comprising a handle, a shaft and an actuating part, characterised by a gastight cover surrounding the shaft, wherein the cover is provided with a coupler that has a feed- through opening with a loskable seal,

  9. Weather Instruments.

    Science.gov (United States)

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities to measure various weather phenomena. Directions for constructing a weather station are included. Instruments including rain gauges, thermometers, wind vanes, wind speed devices, humidity devices, barometers, atmospheric observations, a dustfall jar, sticky-tape can, detection of gases in the air, and pH of…

  10. Mechanisms regulating amphipod population density within macroalgal communities with low predator impact

    Directory of Open Access Journals (Sweden)

    Hartvig Christie

    2004-04-01

    Full Text Available In eight mesocosms (land based basins macroalgae communities with associated fauna were transplanted from the sea and established during two years. Then, different doses of nutrients (N and P were added to the basins throughout the following three years. During the period of nutrient addition, macroinvertebrate grazers showed seasonal fluctuations with densities usually between 500,000 and 1 million individuals per mesocosm during summer and to a level of about 100,000 during winter. The macroinvertebrate grazers mainly consisted of about 10 species of amphipods and isopods, among which the amphipod Gammarus locusta dominated strongly by biomass. Although the number of predators was very low, the grazer populations never reached a density where considerable grazing impact could be found on the macroalgae. No increase in grazer density was found in the basins with improved nutrient conditions. Thus food quality may be insufficient for further population growth, or density dependant regulation mechanisms may have prevented the grazers from flourishing and overgrazing the system. In aquarium experiments we showed that G. locusta could grow and reproduce on Fucus serratus, Ulva lactuca, periphyton and detritus, and that cannibalism by adult G. locusta on juveniles may have great impact on the population growth. The basins were run with a water flow through system. Nets were placed in front of the inflow and outflow tubes to measure immigration and emigration. Only few individuals (and no Gammarus sp. were recorded in the inflowing water, while high numbers of both amphipods and isopods were found in the outflowing water. Emigration reached peak values during night-time, and it was then two to three times as high as during day-time. Emigration of mobile grazers from the basins amounted to 1-2% of the standing stock daily. These mechanisms that regulate grazers do contribute to maintenance of the seaweed dominance and thus the stability of the seaweed

  11. Impact of silver metallization and electron irradiation on the mechanical deformation of polyimide films

    Science.gov (United States)

    Muradov, A. D.; Mukashev, K. M.; Yar-Mukhamedova, G. Sh.; Korobova, N. E.

    2017-11-01

    The impact of silver metallization and electron irradiation on the physical and mechanical properties of polyimide films has been studied. The metal that impregnated the structure of the polyimide substrate was 1-5 μm. The surface coatings contained 80-97% of the relative silver mirror in the visible and infrared regions. Irradiation was performed at the ELU-6 linear accelerator with an average beam electron energy of 2 MeV, an integral current of up to 1000 μA, a pulse repetition rate of 200 Hz, and a pulse duration of 5 μs. The absorbed dose in the samples was 10, 20, 30, and 40 MGy. The samples were deformed at room temperature under uniaxial tension on an Instron 5982 universal testing system. The structural changes in the composite materials that result from the impact of the physical factors were studied using an X-ray diffractometer DRON-2M in air at 293 K using Cu K α radiation (λαCu = 1.5418 Å). A substantial growth of mechanical characteristics resulting from the film metallization, as compared to the pure film, was observed. The growth of the ultimate strength by Δσ = 105 MPa and the plasticity by Δɛ = 75% is connected with the characteristics of the change of structure of the metallized films and the chemical etching conditions. The electron irradiation of the metallized polyimide film worsens its elastic and strength characteristics due to the formation of new phases in the form of silver oxide in the coating. The concentration of these phases increased with increasing dose, which was also the result of the violation of the ordered material structure, namely, the rupture of polyimide macromolecule bonds and the formation of new phases of silver in the coating. A mathematical model was obtained that predicts the elastic properties of silver metallized polyimide films. This model agrees with the experimental data.

  12. Agricultural Intensification as a Mechanism of Adaptation to Climate Change Impacts

    Science.gov (United States)

    Kyle, P.; Calvin, K. V.; le Page, Y.; Patel, P.; West, T. O.; Wise, M. A.

    2015-12-01

    The research, policy, and NGO communities have devoted significant attention to the potential for agricultural intensification, or closure of "yield gaps," to alleviate future global hunger, poverty, climate change impacts, and other threats. However, because the research to this point has focused on biophysically attainable yields—assuming optimal choices under ideal conditions—the presently available work has not yet addressed the likely responses of the agricultural sector to real-world conditions in the future. This study investigates endogenous agricultural intensification in response to global climate change impacts—that is, intensification independent of policies or other exogenous interventions to promote yield gap closure. The framework for the analysis is a set of scenarios to 2100 in the GCAM global integrated assessment model, enhanced to include endogenous irrigation, fertilizer application, and yields, in each of 283 land use regions, with maximum yields based on the 95th percentile of attainable yields in a recent global assessment. We assess three levels of agricultural climate impacts, using recent global gridded crop model datasets: none, low (LPJmL), and high (Pegasus). Applying formulations for decomposition of climate change impacts response developed in prior AgMIP work, we find that at the global level, availability of high-yielding technologies mitigates price shocks and shifts the agricultural sector's climate response modestly towards intensification, away from cropland expansion and reduced production. At the regional level, the behavior is more complex; nevertheless, availability of high-yielding production technologies enhances the inter-regional shifts in agricultural production that are induced by climate change, complemented by commensurate changes in trade patterns. The results highlight the importance of policies to facilitate yield gap closure and inter-regional trade as mechanisms for adapting to climate change

  13. Interfacing to accelerator instrumentation

    International Nuclear Information System (INIS)

    Shea, T.J.

    1995-01-01

    As the sensory system for an accelerator, the beam instrumentation provides a tremendous amount of diagnostic information. Access to this information can vary from periodic spot checks by operators to high bandwidth data acquisition during studies. In this paper, example applications will illustrate the requirements on interfaces between the control system and the instrumentation hardware. A survey of the major accelerator facilities will identify the most popular interface standards. The impact of developments such as isochronous protocols and embedded digital signal processing will also be discussed

  14. Numerical analysis of thermal impact on hydro-mechanical properties of clay

    Directory of Open Access Journals (Sweden)

    Xuerui Wang

    2014-10-01

    Full Text Available As is known, high-level radioactive waste (HLW is commonly heat-emitting. Heat output from HLW will dissipate through the surrounding rocks and induce complex thermo-hydro-mechanical-chemical (THMC processes. In highly consolidated clayey rocks, thermal effects are particularly significant because of their very low permeability and water-saturated state. Thermal impact on the integrity of the geological barriers is of most importance with regard to the long-term safety of repositories. This study focuses on numerical analysis of thermal effects on hydro-mechanical properties of clayey rock using a coupled thermo-mechanical multiphase flow (TH2M model which is implemented in the finite element programme OpenGeoSys (OGS. The material properties of the numerical model are characterised by a transversal isotropic elastic model based on Hooke's law, a non-isothermal multiphase flow model based on van Genuchten function and Darcy's law, and a transversal isotropic heat transport model based on Fourier's law. In the numerical approaches, special attention has been paid to the thermal expansion of three different phases: gas, fluid and solid, which could induce changes in pore pressure and porosity. Furthermore, the strong swelling and shrinkage behaviours of clayey material are also considered in the present model. The model has been applied to simulate a laboratory heating experiment on claystone. The numerical model gives a satisfactory representation of the observed material behaviour in the laboratory experiment. The comparison of the calculated results with the laboratory findings verifies that the simulation with the present numerical model could provide a deeper understanding of the observed effects.

  15. Impact of Gastric Acid Induced Surface Changes on Mechanical Behavior and Optical Characteristics of Dental Ceramics.

    Science.gov (United States)

    Kulkarni, Aditi; Rothrock, James; Thompson, Jeffery

    2018-01-14

    To test the impact of exposure to artificial gastric acid combined with toothbrush abrasion on the properties of dental ceramics. Earlier research has indicated that immersion in artificial gastric acid has caused increased surface roughness of dental ceramics; however, the combined effects of acid immersion and toothbrush abrasion and the impact of increased surface roughness on mechanical strength and optical properties have not been studied. Three commercially available ceramics were chosen for this study: feldspathic porcelain, lithium disilicate glass-ceramic, and monolithic zirconium oxide. The specimens (10 × 1 mm discs) were cut, thermally treated as required, and polished. Each material was divided into four groups (n = 8 per group): control (no exposure), acid only, brush only, acid + brush. The specimens were immersed in artificial gastric acid (50 ml of 0.2% [w/v] sodium chloride in 0.7% [v/v] hydrochloric acid mixed with 0.16 g of pepsin powder, pH = 2) for 2 minutes and rinsed with deionized water for 2 minutes. The procedure was repeated 6 times/day × 9 days, and specimens were stored in deionized water at 37°C. Toothbrush abrasion was performed using an ISO/ADA design brushing machine for 100 cycles/day × 9 days. The acid + brush group received both treatments. Specimens were examined under SEM and an optical microscope for morphological changes. Color and translucency were measured using spectrophotometer CIELAB coordinates (L*, a*, b*). Surface gloss was measured using a gloss meter. Surface roughness was measured using a stylus profilometer. Biaxial flexural strength was measured using a mechanical testing machine. The data were analyzed by one-way ANOVA followed by Tukey's HSD post hoc test (p gloss, and surface roughness for porcelain and e.max specimens. No statistically significant changes were found for any properties of zirconia specimens. The acid treatment affected the surface roughness, color, and gloss of porcelain and e

  16. An Instrumental Variable Probit (IVP Analysis on Depressed Mood in Korea: The Impact of Gender Differences and Other Socio-Economic Factors

    Directory of Open Access Journals (Sweden)

    Lara Gitto

    2015-08-01

    Full Text Available Background Depression is a mental health state whose frequency has been increasing in modern societies. It imposes a great burden, because of the strong impact on people’s quality of life and happiness. Depression can be reliably diagnosed and treated in primary care: if more people could get effective treatments earlier, the costs related to depression would be reversed. The aim of this study was to examine the influence of socio-economic factors and gender on depressed mood, focusing on Korea. In fact, in spite of the great amount of empirical studies carried out for other countries, few epidemiological studies have examined the socio-economic determinants of depression in Korea and they were either limited to samples of employed women or did not control for individual health status. Moreover, as the likely data endogeneity (i.e. the possibility of correlation between the dependent variable and the error term as a result of autocorrelation or simultaneity, such as, in this case, the depressed mood due to health factors that, in turn might be caused by depression, might bias the results, the present study proposes an empirical approach, based on instrumental variables, to deal with this problem. Methods Data for the year 2008 from the Korea National Health and Nutrition Examination Survey (KNHANES were employed. About seven thousands of people (N= 6,751, of which 43% were males and 57% females, aged from 19 to 75 years old, were included in the sample considered in the analysis. In order to take into account the possible endogeneity of some explanatory variables, two Instrumental Variables Probit (IVP regressions were estimated; the variables for which instrumental equations were estimated were related to the participation of women to the workforce and to good health, as reported by people in the sample. Explanatory variables were related to age, gender, family factors (such as the number of family members and marital status and socio

  17. An Instrumental Variable Probit (IVP) analysis on depressed mood in Korea: the impact of gender differences and other socio-economic factors.

    Science.gov (United States)

    Gitto, Lara; Noh, Yong-Hwan; Andrés, Antonio Rodríguez

    2015-04-16

    Depression is a mental health state whose frequency has been increasing in modern societies. It imposes a great burden, because of the strong impact on people's quality of life and happiness. Depression can be reliably diagnosed and treated in primary care: if more people could get effective treatments earlier, the costs related to depression would be reversed. The aim of this study was to examine the influence of socio-economic factors and gender on depressed mood, focusing on Korea. In fact, in spite of the great amount of empirical studies carried out for other countries, few epidemiological studies have examined the socio-economic determinants of depression in Korea and they were either limited to samples of employed women or did not control for individual health status. Moreover, as the likely data endogeneity (i.e. the possibility of correlation between the dependent variable and the error term as a result of autocorrelation or simultaneity, such as, in this case, the depressed mood due to health factors that, in turn might be caused by depression), might bias the results, the present study proposes an empirical approach, based on instrumental variables, to deal with this problem. Data for the year 2008 from the Korea National Health and Nutrition Examination Survey (KNHANES) were employed. About seven thousands of people (N= 6,751, of which 43% were males and 57% females), aged from 19 to 75 years old, were included in the sample considered in the analysis. In order to take into account the possible endogeneity of some explanatory variables, two Instrumental Variables Probit (IVP) regressions were estimated; the variables for which instrumental equations were estimated were related to the participation of women to the workforce and to good health, as reported by people in the sample. Explanatory variables were related to age, gender, family factors (such as the number of family members and marital status) and socio-economic factors (such as education

  18. The impact of instrument field of view on measurements of cloudy-sky spectral radiances from space: application to IRIS and IMG

    Energy Technology Data Exchange (ETDEWEB)

    Brindley, H.E. E-mail: h.brindley@ic.ac.uk; Harries, J.E

    2003-05-15

    Spatially resolved images from the MODerate Resolution Imaging Spectrometer (MODIS) instrument are used to investigate the impact of a change in spatial field of view, from that typical of the Nimbus 4 Infrared Interferometer Spectrometer (IRIS) to that of the Interferometric Monitor for Greenhouse Gases (IMG), upon the spectral outgoing longwave radiation (OLR). Considering all-sky conditions it is found that for a typical tropical scene, approximately 150 paired measurements are required to obtain agreement to within {+-}2 K in the average brightness temperature (T{sub B}), in the most transparent window channels. At mid-latitudes, the reduced scene variability means that fewer observations are required to meet the same criterion. For clear- and cloudy-sky separation a simple threshold technique based on the window T{sub B} and underlying sea-surface temperature tends to result in a systematic underestimate of the average cloudy T{sub B} by the larger field of view. A better estimate can be obtained by applying a double threshold to discriminate against the most mixed scenes.

  19. Mechanics

    CERN Document Server

    Hartog, J P Den

    1961-01-01

    First published over 40 years ago, this work has achieved the status of a classic among introductory texts on mechanics. Den Hartog is known for his lively, discursive and often witty presentations of all the fundamental material of both statics and dynamics (and considerable more advanced material) in new, original ways that provide students with insights into mechanical relationships that other books do not always succeed in conveying. On the other hand, the work is so replete with engineering applications and actual design problems that it is as valuable as a reference to the practicing e

  20. An MJO-Mediated Mechanism to Explain ENSO and IOD Impacts on East African Short Rains

    Science.gov (United States)

    Zaitchik, B. F.; Berhane, F.; Gnanadesikan, A.

    2015-12-01

    Previous studies have found that the El Nino Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) have significant impacts on rainfall over East Africa (EA) during the short rains (Oct-Dec). However, not all ENSO and IOD events are associated with significant precipitation anomalies over EA. Our analysis shows that the IOD and ENSO influence EA rainfall by modifying the MJO. Composite analysis of rainfall and outgoing longwave radiation data show that the MJO over the Indian Ocean (phases 2 and 3 of the Wheeler and Hendon index) is associated with significant increase in precipitation over EA during El Niño. In La Niña and non-ENSO years, the MJO over the Indian Ocean has very weak impacts on EA convection and precipitation. Although previous studies have found that El Niño / La Niña events are associated with anomalous wetness/dryness over EA, the associations are not evident in the absence of the MJO. Similarly, the IOD exhibits strong associations with EA precipitation when there is MJO activity over the Indian Ocean. During the positive phase of the IOD, the MJO over the Indian Ocean has impacts that extend to EA. In the absence of the MJO, however, the IOD shows weak associations with EA precipitation. Furthermore, there are more MJO days in the Indian Ocean during El Niño and positive IOD events, which implies stronger impacts on EA. During La Niña events more MJO days are observed in the Pacific Ocean, favoring subsidence over the western Indian Ocean and dry anomalies over EA. These observations suggest two critical MJO-related questions that must be addressed in order to explain EA short rain variability typically attributed to ENSO or IOD: first, how do ENSO and IOD modify background conditions in a way that causes Indian Ocean MJO activity to be more strongly connected to EA under El Niño and IOD positive conditions, and second, why is it that El Niño and IOD positive states slow MJO propagation over the Indian Ocean and speed it over

  1. Nuclear instrumentation

    International Nuclear Information System (INIS)

    Weill, Jacky; Fabre, Rene.

    1981-01-01

    This article sums up the Research and Development effort at present being carried out in the five following fields of applications: Health physics and Radioprospection, Control of nuclear reactors, Plant control (preparation and reprocessing of the fuel, testing of nuclear substances, etc.), Research laboratory instrumentation, Detectors. It also sets the place of French industrial activities by means of an estimate of the French market, production and flow of trading with other countries [fr

  2. Divided Instruments

    Science.gov (United States)

    Chapman, A.; Murdin, P.

    2000-11-01

    Although the division of the zodiac into 360° probably derives from Egypt or Assyria around 2000 BC, there is no surviving evidence of Mesopotamian cultures embodying this division into a mathematical instrument. Almost certainly, however, it was from Babylonia that the Greek geometers learned of the 360° circle, and by c. 80 BC they had incorporated it into that remarkably elaborate device gener...

  3. Instrumentation development

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Areas being investigated for instrumentation improvement during low-level pollution monitoring include laser opto-acoustic spectroscopy, x-ray fluorescence spectroscopy, optical fluorescence spectroscopy, liquid crystal gas detectors, advanced forms of atomic absorption spectroscopy, electro-analytical chemistry, and mass spectroscopy. Emphasis is also directed toward development of physical methods, as opposed to conventional chemical analysis techniques for monitoring these trace amounts of pollution related to energy development and utilization

  4. Instrumentation maintenance

    International Nuclear Information System (INIS)

    Mack, D.A.

    1976-09-01

    It is essential to any research activity that accurate and efficient measurements be made for the experimental parameters under consideration for each individual experiment or test. Satisfactory measurements in turn depend upon having the necessary instruments and the capability of ensuring that they are performing within their intended specifications. This latter requirement can only be achieved by providing an adequate maintenance facility, staffed with personnel competent to understand the problems associated with instrument adjustment and repair. The Instrument Repair Shop at the Lawrence Berkeley Laboratory is designed to achieve this end. The organization, staffing and operation of this system is discussed. Maintenance policy should be based on studies of (1) preventive vs. catastrophic maintenance, (2) records indicating when equipment should be replaced rather than repaired and (3) priorities established to indicate the order in which equipment should be repaired. Upon establishing a workable maintenance policy, the staff should be instructed so that they may provide appropriate scheduled preventive maintenance, calibration and corrective procedures, and emergency repairs. The education, training and experience of the maintenance staff is discussed along with the organization for an efficient operation. The layout of the various repair shops is described in the light of laboratory space and financial constraints

  5. The IKARUS instrument

    International Nuclear Information System (INIS)

    Gerster, H.J.; Stein, G.

    1994-01-01

    When the Federal Government decided on a 25% reduction of CO 2 emissions till 2005 in 1990 the necessity resulted that an instrument has to be developed for the analysis and assessment of the ecological, economic and energetic impact of different reduction strategies. The development task was awarded by the BMFT to the Research Centre Juelich in cooperation with well-known institutions of energy system research. The total instrument is scheduled to be finished by the end of 1994. For the decentral use of the instrument by a wide specialist public the developed models and data banks which are equipped with a user-friendly surface are suited for larger PCs (486, 16 MB RAM/500-1000 MB ROM). (orig.) [de

  6. Information technology impact on nuclear power plant documentation. Report prepared within the framework of the International Working Group on Nuclear Power Plant Control and Instrumentation

    International Nuclear Information System (INIS)

    2002-04-01

    related Advisory Group meeting on Information Technology Impact on NPP Design Process and Plant Documentation was held in Vienna, Austria in April 2000. This report is intended mainly for the use of plant managers, project managers, Instrumentation and Control (I and C) system designers, system engineers, operations managers, operators, and other plant information users

  7. Information technology impact on nuclear power plant documentation. Report prepared within the framework of the International Working Group on Nuclear Power Plant Control and Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    related Advisory Group meeting on Information Technology Impact on NPP Design Process and Plant Documentation was held in Vienna, Austria in April 2000. This report is intended mainly for the use of plant managers, project managers, Instrumentation and Control (I and C) system designers, system engineers, operations managers, operators, and other plant information users.

  8. Interannual Variation in Offshore Advection of Amazon-Orinoco Plume Waters: Observations, Forcing Mechanisms, and Impacts

    Science.gov (United States)

    Fournier, S.; Vandemark, D. C.; Gaultier, L.; Lee, T.; Jonsson, B. F.; Gierach, M. M.

    2017-12-01

    Sea surface salinity (SSS) and sea surface temperature (SST) variations in the tropical Atlantic east of the Lesser Antilles, a region impacted by freshwater advection from the Amazon and Orinoco Rivers have potential implications to late-summer tropical cyclones (TCs). This study examines these variations during late summer and their forcing mechanisms using observations. During the period 2010-2014, the largest difference in plume-affected area, defined as the extent covered by SSS lower than 35.5 pss, is found between 2011 and 2014. Plume waters covered 92% (60%) of the study region in 2011 (2014) with the averaged SSS in the study region being 2-pss lower in 2011. Lagrangian particle tracking based on satellite-derived ocean currents is used to diagnose the impacts of the river plumes on SSS and SST during 2010-2014. Northward freshwater flux in the summer of 2014 is significantly weaker than those in 2010-2013. This is not due to interannual discharge variability, but significant changes in eddy-driven transport and cross-shore winds. In particular, the stronger cross-shore wind in May 2014 restricted offshore freshwater flow, leading to a smaller extent of the plume-affected area. Persistent SST gradients are often found near the plume edge, which may have implication to ocean-atmosphere coupling associated with TC-related convection. SST in the study region is 1°C higher in 2010 than in other years, and is related to basin-scale ocean-atmosphere processes. Interannual variation in Amazon advective pathways and the associated SSS changes are also influenced by changes in the ITCZ position between 2011 and 2014.

  9. Leaving the labour market later in life: how does it impact on mechanisms for health?

    Science.gov (United States)

    Whitley, Elise; Popham, Frank

    2017-12-01

    Negative associations between non-employment and health among older people are well established and are potentially important for successful ageing. However, opportunities to improve health through re-employment or extending working lives are limited as later-life exits from employment are often unwanted and permanent. We aim to establish a greater understanding of the psychosocial mechanisms underlying non-employment and health associations in older people to identify modifiable pathways through which the negative impact of non-employment can be ameliorated. Using multilevel analysis of four waves of repeated panel data from a representative sample of 1551 older men and women reaching state retirement age in the West of Scotland from 1987/1988 to 2000/2004, we explored respondents' strength of agreement with 20 statements relating to their self-defined employment status, covering themes of functioning, social engagement, self-esteem, mental engagement, stress, and control and autonomy. Compared with those in employment, respondents who were retired, unemployed, sick/disabled and home makers were more likely to agree that this resulted in poor social engagement, low self-esteem and, with the possible exception of retirees, reduced mental engagement. Associations were particularly marked among unemployed and sick/disabled respondents who also agreed that their status was a source of worry and prevented them from feeling in control. Older people who are not in employment are at higher risk of poor physical and mental health. Interventions targeting psychosocial mechanisms such as social and mental engagement and self-esteem offer potentially valuable opportunities to improve health outcomes and promote successful ageing. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. Evolution of fuel rod support under irradiation impact on the mechanical behaviour of fuel assemblies

    International Nuclear Information System (INIS)

    Billerey, Antoine; Waeckel, Nicolas

    2005-01-01

    New fuel management targets imply to increase fuel assembly discharge burnup. Therefore, the prediction of the mechanical behaviour of the irradiated fuel assembly is essential such as excessive fuel assembly distortion induce incomplete Rod Cluster Control Assembly insertion problems (safety issue) or fuel rod vibration induced wear leading to leaking rods (plant operation problems). Within this framework, one of the most important parameter is the knowledge of the fuel rod support in the grid cell because it directly governs the mechanical behaviour of the fuel assembly and consequently allows to predict the behaviour of irradiated structures in terms of (1) axial and lateral deformation (global behaviour of the assembly) and (2) rod vibration induced wear (local behaviour of the rod). Generally, fuel rod support is provided by a spring-dimple system fixed to the grid. During irradiation, the spring force decreases and a gap between the rod and the spring may occur. This phenomenon is due to (1) stress relieving in the spring and in the dimples, (2) grid growth and (3) reduction of the rod diameter. Two models have been developed to predict the behaviour of the rod in the cell. The first model is dedicated to the evaluation of the spring force relaxation during irradiation. The second one can assess the rotation characteristic of the fuel rod in the cell, function of the spring force. The main input parameters are (1) the creep laws of the grid materials, (2) the growth law of the grid, (3) the evolution of rod diameter and (4) the design of the fuel rod support. The aim of this paper is to: (1) evaluate the consequences of grid support design modifications on the rod vibration sensitivity in terms of predicted rod to grid maximum gap during irradiation and time in operation with an open rod to grid gap, (2) evaluate, using a linear or non-linear Finite Element assembly model, the impact of the evolution of grid support under irradiation on the overall mechanical

  11. Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-01-01

    The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

  12. Impact of Cyclic Loading on Chloride Diffusivity and Mechanical Performance of RC Beams under Seawater Corrosion

    Directory of Open Access Journals (Sweden)

    Sen Pang

    2017-01-01

    Full Text Available An experimental study was conducted to investigate the impact of cyclic loading on the mechanical performance and chloride diffusivity of RC beams exposed to seawater wet-dry cycles. To induce initial damage to RC beam specimen, cyclic loading controlled by max load and cycles was applied. Then beam specimens underwent 240 wet-dry cycles of seawater. Results show that the chloride content increased as max load and cycle increased. The chloride content at steel surface increased approximatively linearly as average crack width increased. Moreover, the max load had more influence on chloride content at steel surface than cycle. The difference of average chloride diffusion coefficient between tension and compression concrete was little at uncracked position. Average chloride diffusion coefficient increased as crack width increased when crack width was less than 0.11 mm whereas the increasing tendency was weak when crack width exceeded 0.11 mm. The residual yield load and ultimate load of RC beams decreased as max load and cycle increased. Based on univariate analysis of variance, the max load had more adverse effect on yield load and ultimate load than cycle.

  13. Quenching of exciton luminescence due to impact ionization and mechanisms of electron relaxation in cadmium sulphide

    International Nuclear Information System (INIS)

    Kagan, V.D.; Karpenko, S.L.; Katilyus, R.

    1989-01-01

    Quenching of exciton luminescence in the constant electric field in cadmium sulfide at 1.8K, caused by impact ionization of free and delocalization of bound excitons by hot electrons is observed. When the field is increase up to 1 kW/cm continuous transfer from the Taundsen-Shockley law to the Davydov-Wolf one takes place. Among the samples studied pure samples are distinguished by the exciton spectrum, where, as it is shown in the work, the high-energy electrons lose quasipulse, radiating spontaneously piezophonons; in other samples scattering on impurities prevails. Theoretical processing of data on the bound exciton radiation line quenching in the moderate field region presents about 10 -4 values in pure and about 5x10 -6 cm ones in other samples for the 4 MeV energy electron free flight length. So, the optical methods used allowed one to determine high-energy electron relaxation mechanisms, prevailing in CdS at low temperature

  14. PROTECTIVE COATINGS OF FIBER BRAGG GRATING FOR MINIMIZING OF MECHANICAL IMPACT ON ITS WAVELENGTH CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    A. S. Munko

    2015-03-01

    Full Text Available The paper deals with the scheme for the study of the Bragg wavelength shift dependence on the applied tensile force. Samples of fiber Bragg gratings with different coatings have been studied: the restored acrylate coating, the heatshrinkable fusion splice protection sleeve without metal rod, the heat-shrinkable fusion splice protection sleeve with a metal rod, the metal capillary, polyvinylchloride tube. For different coatings of diffractive structure, dependences of wavelength shift for the Bragg grating resonance have been obtained on the tensile strength applied to the ends of an optical fiber. It was determined that the studied FBG coatings give the possibility to reduce the mechanical impact on the Bragg wavelength shift for 1.1-15 times as compared to an uncoated waveguide. The most effective version of coated fiber Bragg grating is the heatshrinkable fusion splice protection sleeve with a metal rod. When the force (equal to 6 N is applied to the 100 mm optical fiber area with the inscribed diffractive structure, the Bragg wavelength shift is 7.5 nm for the unprotected sample and 0.5 nm for the one coated with the heat-shrinkable fusion splice protection sleeve.

  15. Fire risk analysis, fire simulation, fire spreading and impact of smoke and heat on instrumentation electronics - State-of-the-Art Report

    International Nuclear Information System (INIS)

    Roewekamp, M.; Bertrand, R.; Bonneval, F.; Hamblen, D.; Siu, N.; Aulamo, H.; Martila, J.; Sandberg, J.; Virolainen, R.

    2000-01-01

    Numerous fire PSAs (probabilistic safety assessments) have shown that fire can be a major contributor to nuclear power plant risk. However, there are considerable uncertainties in the results of these assessments, due to significant gaps in current abilities to perform realistic assessments. These gaps involve multiple aspects of fire PSA, including the estimation of the probability of important fire scenarios, the modeling of fire growth and suppression, the prediction of fire-induced damage to equipment (including the effects of smoke), and the treatment of plant and operator responses to the fire. In response to recommendations of /VIR 93/, CSNI/PWG5 established a Task Group to review the present status and maturity of current methods used in fire risk assessments for operating nuclear power plants. The Task Group issued a questionnaire in May 1997 to all nuclear power generating OECD countries. The prime focus of the questionnaire (see Appendix A) was on a number of important issues in fire PSA: Fire PSA methodology and applications; Fire simulation codes; Ignition and damageability data; Modeling of fire spread on cables or other equipment; Modeling of smoke production and spread; Impact of smoke and heat on instrumentation, electronics, or other electrical equipment; Impact of actual cable fires on safety systems. The questionnaire requested specific information on these topics (e.g., computer codes used in fire PSAs, the physical parameters used to model ignition). Responses to the questionnaire were provided by Finland, France, Germany, Hungary, Japan, Spain, Switzerland, United Kingdom, and the USA. This report summarizes the questionnaire responses and thereby: a) provides a perspective on the current fire PSA state of the art (SOAR) with respect to the issues listed above, and b) provides numerous references for more detailed information regarding these issues. The main responsibility for writing different chapters of this report was divided between some

  16. Liquid impact erosion mechanism and theoretical impact stress analysis in TiN-coated steam turbine blade materials

    International Nuclear Information System (INIS)

    Lee, M.K.; Kim, W.W.; Rhee, C.K.; Lee, W.J.

    1999-01-01

    Coating of TiN film was done by reactive magnetron sputter ion plating to improve the liquid impact erosion resistance of steam turbine blade materials, 12Cr steel and Stellite 6B, for nuclear power plant application. TiN-coated blade materials were initially deformed with depressions due to plastic deformation of the ductile substrate. The increase in the curvature in the depressions induced stress concentration with increasing number of impacts, followed by circumferential fracture of the TiN coating due to the circular propagation of cracks. The liquid impact erosion resistance of the blade materials was greatly improved by TiN coating done with the optimum ion plating condition. Damage decreased with increasing TiN coating thickness. According to the theoretical analysis of stresses generated by liquid impact, TiN coating alleviated the impact stress of 12Cr steel and Stellite 6B due to stress attenuation and stress wave reactions such as reflection and transmission at the coating-substrate interface

  17. Effect of impact energy on damage resistance and mechanical property of C/SiC composites under low velocity impact

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Hui, E-mail: phdhuimei@yahoo.com; Yu, Changkui; Xu, Yawei; Han, Daoyang; Cheng, Laifei

    2017-02-27

    The present study investigated the damage resistance of two dimensional carbon fiber reinforced silicon carbide (C/SiCs) composites subjected to low velocity impact (LVI). Damage microstructures of specimens under different impact energies (E{sub i}) were characterized by infrared thermography, X-ray computed tomography and scanning electron microscopy. The real damage radii of specimens were found to change slightly with E{sub i}, whereas apparent damage radii where much larger. Overall, the fabricated 2D C/SiC composites exhibited good damage resistance to LVI with nominal post-impact tensile strengths remaining at 89.4%, 83.35%, 76.97%, and 74.84% of their pre-impacted counterpart of 158 MPa, for impact energies of 3, 4, 5, and 6 J, respectively. Compared with the as-received one, after LVI real tensile strengths of the C/SiC composite specimens increased by 5.84% for the E{sub i} of 3 J, 9.27% for 4 J, −1.83% for 5 J, −3.16% for 6 J.

  18. Microstructural response and grain refinement mechanism of commercially pure titanium subjected to multiple laser shock peening impacts

    International Nuclear Information System (INIS)

    Lu, J.Z.; Wu, L.J.; Sun, G.F.; Luo, K.Y.; Zhang, Y.K.; Cai, J.; Cui, C.Y.; Luo, X.M.

    2017-01-01

    The microstructural response and grain subdivision process in commercially pure (CP) titanium subjected to multiple laser shock peening (LSP) impacts were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations. The micro-hardness curves as a function of the impact time were also determined. The deformation-induced grain refinement mechanism of the close-packed hexagonal (hcp) material by laser shock wave was subsequently analyzed. Experimental results showed that uniform equiaxed grains with an average size of less than 50 nm were generated due to the ultra-high plastic strain induced by multiple LSP impacts. Special attention was paid to four types of novel deformation-induced microstructural features, including a layered slip band in the tension deformation zone, and inverse-transformation martensite, micro-twin grating and micro-twin collision in the compression deformation zone. Furthermore, the grain refinement mechanism in the near-surface layer of CP titanium subjected to multiple LSP impacts contains two types of simultaneous subdivision modes: multi-directional mechanical twin (MT)-MT intersections at (sub)micrometer scale, and the intersection between longitudinal secondary MTs and transverse dislocation walls at nanometer scale. In addition, both grain refinement (nanocrystallization) and the existence of a small amount of inverse-transformation martensite induced by multiple LSP impacts contribute to an increase in the micro-hardness of the near-surface layer.

  19. Temporal Changes in Left Ventricular Mechanics: Impact of Bed Rest and Exercise

    Science.gov (United States)

    Scott, Jessica M.; Matz, Timothy; Caine, Timothy; Martin, David S.; Downs, Meghan; Ploutz-Snyder, Lori

    2014-01-01

    BACKGROUND Current techniques used to assess cardiac function following spaceflight or head-down tilt bed rest (HDTBR) involve invasive and time consuming procedures such as Swan-Ganz catheterization or cardiac magnetic resonance imaging. An alternative approach, echocardiography, can monitor cardiac morphology and function via sequential measurements of left ventricular (LV) mass and ejection fraction (EF). However, LV mass and EF are insensitive measures of early (subclinical) cardiac deconditioning, and a decrease in LV mass and EF become evident only once significant deconditioning has already occurred. The use of more sensitive and specific echocardiographic techniques such as speckle tracking imaging may address the current limitations of conventional cardiac imaging techniques to provide insight into the magnitude and time course of cardiac deconditioning. METHODS Speckle tracking assessment of longitudinal, radial, and circumferential strain and twist was used to evaluate the impact of 70 days of HDTBR (n=7) and HDTBR + exercise (n=11) on temporal changes in LV mechanics. Echocardiograms were performed pre (BR-2), during (BR31, 70), and following (BR+4hr) HDTBR. Multi-level modeling was used to evaluate the effect of HDTBR condition (Control, Exercise) on cardiac variables. RESULTS Compared to BR-2, longitudinal (BR-2: - 19.0 +/- 1.8%; BR31: -15.9 +/- 2.4%; BR70: -14.9 +/- 2.4%; BR+4hr: -16.0 +/- 2.1%) and radial (BR-2: 15.0 +/- 1.9%; BR31: 12.3 +/- 2.4%; BR70: 11.3 +/- 2.2%; BR+4hr: 13.5 +/- 2.5% ) strains were significantly impaired during and following bed rest (pmechanics for longitudinal strain (BR-2: -19.1 +/- 1.5%; BR 31: -19.0 +/- 2.4%; BR70: -19.1 +/- 2.7%; BR+4hr: -17.8 +/- 2.1%), radial strain (BR-2: 13.8 +/- 2.4; BR31: 14.7 +/- 2.4; BR70: 14.4 +/- 1.6; BR+4hr: 14.4 +/- 2.4), and twist (BR-2: 17.8 +/- 3.6deg; BR31: 18.0 +/- 3.6deg; BR70: 18.2 +/- 5.9deg; BR+4hr: 18.3 +/- 4.2deg). CONCLUSIONS Speckle-tracking echocardiography provides important

  20. Assessing the Organisational Impact of External Quality Assurance: Hypothesising Key Dimensions and Mechanisms

    Science.gov (United States)

    Stensaker, Bjørn; Leiber, Theodor

    2015-01-01

    The aim of the article is to provide a framework in which the organisational impact of external quality assurance (EQA) can be assessed. Based on existing studies of the impact of EQA in universities and colleges it is suggested that greater systematisation of how impact is measured is needed for a better understanding of how EQA can be used as a…

  1. Instrumentation for tomograph positioning

    International Nuclear Information System (INIS)

    Frenkel, A.D.B.; Castello Branco, L.M.; Reznik, D.S.; Santos, C.A.C.; Borges, J.C.

    1986-01-01

    The COPPE's Nuclear Instrumentation Lab. has been developing researches directed towards the implementation of a Computer-Based Tomography System. Basically, the system reported in this paper can be divided into three major parts: the mechanical part, responsible for the physical movement (Stepper-Motors, table, etc.); the electronic part, which controls the mechanical part and handles the data-acquisition process (microcomputer, interfaces, etc.); and finally, the support of a software-oriented system, including control programs and information processing routines. (Author) [pt

  2. Impact of mechanism vibration characteristics by joint clearance and optimization design of its multi-objective robustness

    Science.gov (United States)

    Zeng, Baoping; Wang, Chao; Zhang, Yu; Gong, Yajun; Hu, Sanbao

    2017-12-01

    Joint clearances and friction characteristics significantly influence the mechanism vibration characteristics; for example: as for joint clearances, the shaft and bearing of its clearance joint collide to bring about the dynamic normal contact force and tangential coulomb friction force while the mechanism works; thus, the whole system may vibrate; moreover, the mechanism is under contact-impact with impact force constraint from free movement under action of the above dynamic forces; in addition, the mechanism topology structure also changes. The constraint relationship between joints may be established by a repeated complex nonlinear dynamic process (idle stroke - contact-impact - elastic compression - rebound - impact relief - idle stroke movement - contact-impact). Analysis of vibration characteristics of joint parts is still a challenging open task by far. The dynamic equations for any mechanism with clearance is often a set of strong coupling, high-dimensional and complex time-varying nonlinear differential equations which are solved very difficultly. Moreover, complicated chaotic motions very sensitive to initial values in impact and vibration due to clearance let high-precision simulation and prediction of their dynamic behaviors be more difficult; on the other hand, their subsequent wearing necessarily leads to some certain fluctuation of structure clearance parameters, which acts as one primary factor for vibration of the mechanical system. A dynamic model was established to the device for opening the deepwater robot cabin door with joint clearance by utilizing the finite element method and analysis was carried out to its vibration characteristics in this study. Moreover, its response model was carried out by utilizing the DOE method and then the robust optimization design was performed to sizes of the joint clearance and the friction coefficient change range so that the optimization design results may be regarded as reference data for selecting bearings

  3. Mechanics

    CERN Document Server

    Chester, W

    1979-01-01

    When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

  4. Impact of the Clean Development Mechanism on wind energy investments in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Tunc, Murat; Pak, Ruhan [Yeditepe Univ., Istanbul (Turkey). Systems Engineering Dept.

    2012-12-01

    As carbon trading continues to be implemented on both a national and an international scale, it is becoming an important factor in renewable energy investment decisions. Turkey, with continuous growth of carbon dioxide emission and energy consumption since 2001, ratified the Kyoto Protocol in 2009 and began registration of projects with greenhouse gas reductions in 2010. In light of these developments, wind energy resources with a potential of 48,000 MW are among the most efficient and effective solutions for clean and sustainable energy in Turkey. The aim of our study is to reveal the importance of the Clean Development Mechanism (CDM) of the Kyoto Protocol on wind energy investment decisions. A broad review of wind energy in Turkey is given, and then, a comprehensive feasibility study of a wind energy firm with a valuation model including Certified Emission Reduction (CER) prices is applied to a case study, the Mega Metallurgy Power. With a holistic and interdisciplinary system engineering approach, results are obtained using comprehensive analysis of technology, emission, and power generation of a wind energy firm linked to a valuation model. This comprehensive model sets the investment decision-making criteria, the enterprise value comparison with total financing. Finally, a sensitivity analysis is run to show that the enterprise value is positively correlated with CER prices. Based on these results, it is concluded that if the world's largest carbon offsetting program, the CDM, prevails after 2012, CER prices will have a positive impact on wind energy firm valuations and related investment decisions. (orig.)

  5. Exercise impacts brain-derived neurotrophic factor plasticity by engaging mechanisms of epigenetic regulation.

    Science.gov (United States)

    Gomez-Pinilla, F; Zhuang, Y; Feng, J; Ying, Z; Fan, G

    2011-02-01

    We have evaluated the possibility that the action of voluntary exercise on the regulation of brain-derived neurotrophic factor (BDNF), a molecule important for rat hippocampal learning, could involve mechanisms of epigenetic regulation. We focused the studies on the Bdnf promoter IV, as this region is highly responsive to neuronal activity. We have found that exercise stimulates DNA demethylation in Bdnf promoter IV, and elevates levels of activated methyl-CpG-binding protein 2, as well as BDNF mRNA and protein in the rat hippocampus. Chromatin immunoprecipitation assay showed that exercise increases acetylation of histone H3, and protein assessment showed that exercise elevates the ratio of acetylated :total for histone H3 but had no effects on histone H4 levels. Exercise also reduces levels of the histone deacetylase 5 mRNA and protein implicated in the regulation of the Bdnf gene [N.M. Tsankova et al. (2006)Nat. Neurosci., 9, 519-525], but did not affect histone deacetylase 9. Exercise elevated the phosphorylated forms of calcium/calmodulin-dependent protein kinase II and cAMP response element binding protein, implicated in the pathways by which neural activity influences the epigenetic regulation of gene transcription, i.e. Bdnf. These results showing the influence of exercise on the remodeling of chromatin containing the Bdnf gene emphasize the importance of exercise on the control of gene transcription in the context of brain function and plasticity. Reported information about the impact of a behavior, inherently involved in the daily human routine, on the epigenome opens exciting new directions and therapeutic opportunities in the war against neurological and psychiatric disorders. © 2010 The Authors. European Journal of Neuroscience © 2010 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  6. Pancreatitis Quality of Life Instrument: Development of a new instrument

    Directory of Open Access Journals (Sweden)

    Wahid Wassef

    2014-02-01

    Full Text Available Objectives: The goal of this project was to develop the first disease-specific instrument for the evaluation of quality of life in chronic pancreatitis. Methods: Focus groups and interview sessions were conducted, with chronic pancreatitis patients, to identify items felt to impact quality of life which were subsequently formatted into a paper-and-pencil instrument. This instrument was used to conduct an online survey by an expert panel of pancreatologists to evaluate its content validity. Finally, the modified instrument was presented to patients during precognitive testing interviews to evaluate its clarity and appropriateness. Results: In total, 10 patients were enrolled in the focus groups and interview sessions where they identified 50 items. Once redundant items were removed, the 40 remaining items were made into a paper-and-pencil instrument referred to as the Pancreatitis Quality of Life Instrument. Through the processes of content validation and precognitive testing, the number of items in the instrument was reduced to 24. Conclusions: This marks the development of the first disease-specific instrument to evaluate quality of life in chronic pancreatitis. It includes unique features not found in generic instruments (economic factors, stigma, and spiritual factors. Although this marks a giant step forward, psychometric evaluation is still needed prior to its clinical use.

  7. Aversive pavlovian responses affect human instrumental motor performance.

    Science.gov (United States)

    Rigoli, Francesco; Pavone, Enea Francesco; Pezzulo, Giovanni

    2012-01-01

    IN NEUROSCIENCE AND PSYCHOLOGY, AN INFLUENTIAL PERSPECTIVE DISTINGUISHES BETWEEN TWO KINDS OF BEHAVIORAL CONTROL: instrumental (habitual and goal-directed) and Pavlovian. Understanding the instrumental-Pavlovian interaction is fundamental for the comprehension of decision-making. Animal studies (as those using the negative auto-maintenance paradigm), have demonstrated that Pavlovian mechanisms can have maladaptive effects on instrumental performance. However, evidence for a similar effect in humans is scarce. In addition, the mechanisms modulating the impact of Pavlovian responses on instrumental performance are largely unknown, both in human and non-human animals. The present paper describes a behavioral experiment investigating the effects of Pavlovian conditioned responses on performance in humans, focusing on the aversive domain. Results showed that Pavlovian responses influenced human performance, and, similar to animal studies, could have maladaptive effects. In particular, Pavlovian responses either impaired or increased performance depending on modulator variables such as threat distance, task controllability, punishment history, amount of training, and explicit punishment expectancy. Overall, these findings help elucidating the computational mechanisms underlying the instrumental-Pavlovian interaction, which might be at the base of apparently irrational phenomena in economics, social behavior, and psychopathology.

  8. Aversive Pavlovian responses affect human instrumental motor performance

    Directory of Open Access Journals (Sweden)

    Francesco eRigoli

    2012-10-01

    Full Text Available In neuroscience and psychology, an influential perspective distinguishes between two kinds of behavioural control: instrumental (habitual and goal-directed and Pavlovian. Understanding the instrumental-Pavlovian interaction is fundamental for the comprehension of decision-making. Animal studies (as those using the negative auto-maintenance paradigm, have demonstrated that Pavlovian mechanisms can have maladaptive effects on instrumental performance. However, evidence for a similar effect in humans is scarce. In addition, the mechanisms modulating the impact of Pavlovian responses on instrumental performance are largely unknown, both in human and non-human animals. The present paper describes a behavioural experiment investigating the effects of Pavlovian conditioned responses on performance in humans, focusing on the aversive domain. Results showed that Pavlovian responses influenced human performance, and, similar to animal studies, could have maladaptive effects. In particular, Pavlovian responses either impaired or increased performance depending on modulator variables such as threat distance, task controllability, punishment history, amount of training, and explicit punishment expectancy. Overall, these findings help elucidating the computational mechanisms underlying the instrumental-Pavlovian interaction, which might be at the base of apparently irrational phenomena in economics, social behaviour, and psychopathology.

  9. Seismic instrumentation

    International Nuclear Information System (INIS)

    1984-06-01

    RFS or Regles Fondamentales de Surete (Basic Safety Rules) applicable to certain types of nuclear facilities lay down requirements with which compliance, for the type of facilities and within the scope of application covered by the RFS, is considered to be equivalent to compliance with technical French regulatory practice. The object of the RFS is to take advantage of standardization in the field of safety, while allowing for technical progress in that field. They are designed to enable the operating utility and contractors to know the rules pertaining to various subjects which are considered to be acceptable by the Service Central de Surete des Installations Nucleaires, or the SCSIN (Central Department for the Safety of Nuclear Facilities). These RFS should make safety analysis easier and lead to better understanding between experts and individuals concerned with the problems of nuclear safety. The SCSIN reserves the right to modify, when considered necessary, any RFS and specify, if need be, the terms under which a modification is deemed retroactive. The aim of this RFS is to define the type, location and operating conditions for seismic instrumentation needed to determine promptly the seismic response of nuclear power plants features important to safety to permit comparison of such response with that used as the design basis

  10. Meteorological instrumentation

    International Nuclear Information System (INIS)

    1982-06-01

    RFS or ''Regles Fondamentales de Surete'' (Basic Safety Rules) applicable to certain types of nuclear facilities lay down requirements with which compliance, for the type of facilities and within the scope of application covered by the RFS, is considered to be equivalent to compliance with technical French regulatory practice. The object of the RFS is to take advantage of standardization in the field of safety , while allowing for technical progress in that field. They are designed to enable the operating utility and contractors to know the rules pertaining to various subjects which are considered to be acceptable by the ''Service Central de Surete des Installations Nucleaires'' or the SCSIN (Central Department for the Safety of Nuclear Facilities). These RFS should make safety analysis easier and lead to better understanding between experts and individuals concerned with the problems of nuclear safety. The SCSIN reserves the right to modify, when considered necessary any RFS and specify, if need be, the terms under which a modification is deemed retroactive. The purpose of this RFS is to specify the meteorological instrumentation required at the site of each nuclear power plant equipped with at least one pressurized water reactor

  11. Power station instrumentation

    International Nuclear Information System (INIS)

    Jervis, M.W.

    1993-01-01

    Power stations are characterized by a wide variety of mechanical and electrical plant operating with structures, liquids and gases working at high pressures and temperatures and with large mass flows. The voltages and currents are also the highest that occur in most industries. In order to achieve maximum economy, the plant is operated with relatively small margins from conditions that can cause rapid plant damage, safety implications, and very high financial penalties. In common with other process industries, power stations depend heavily on control and instrumentation. These systems have become particularly significant, in the cost-conscious privatized environment, for providing the means to implement the automation implicit in maintaining safety standards, improving generation efficiency and reducing operating manpower costs. This book is for professional instrumentation engineers who need to known about their use in power stations and power station engineers requiring information about the principles and choice of instrumentation available. There are 8 chapters; chapter 4 on instrumentation for nuclear steam supply systems is indexed separately. (Author)

  12. A METHOD TO SET-UP CALIBRATION CURVE FOR INSTRUMENTED SPHERE IS100 TO CONTROL MECHANICAL DAMAGE DURING POST-HARVESTING AND HANDLING OF ORANGES

    Directory of Open Access Journals (Sweden)

    Giovanni Carlo Di Renzo

    2009-12-01

    Full Text Available Oranges quality is strictly dependent on their variety, pre-harvest and post-harvest practices. Especially post harvest management is responsible for fruits damages, causing quality deterioration and commercial losses, as underlined by many authors, which studied the influence of individual post harvest operations on the fruit quality. In this article Authors, using an instrumented sphere (IS 100 similar for shape and size to a true orange, showed a method for the control of orange damages along the processing line. Results allow a fundamental knowledge about the critical damage curve, which defines the incidence of the damages during the oranges processing and packaging. Data show that the fruit discharge (bins or boxes discharge and the packaging step are the most critical operations in order to reduce or eliminate the fruits collisions and the consequent damages

  13. Effect of organoclays content and modify the impact on mechanical properties of of bionanocomposites poly (lactic acid ) - PLA

    International Nuclear Information System (INIS)

    Cavalcanti, Shirley N.; Alves, Amanda M.; Agrawal, Pankaj; Silva, Moacy P. da; Araujo, Aylanna P.M.; Araujo, Edcleide M.; Melo, Tomas J.A.

    2015-01-01

    Until recently, it has become important to develop more durable plastic materials to meet the needs of the market, which have wide range of applications. But these materials are from non-renewable sources cause environmental impact due to the large amount of waste they produce. In order to evaluate the effect of organoclay (Brasgel PA and vermiculite) and impact modifier (EMA-GMA) were developed PLA bionanocomposites / Clays through the merge process by melting and rated the content (1, 3 and 5pcr) the mechanical properties of these clays. The clays were organophilizated using a percentage of surfactant based on the capacity of cation exchange. The bionanocomposites were prepared by extrusion followed the injection molding step of the specimens. The clays were characterized by X-ray diffraction (XRD).The bionanocomposites were characterized by the mechanical properties of impact and traction. The techniques of X-ray diffraction showed that organophilization process used was efficient. The mechanical properties were changed, and the impact strength showed considerable gain when the PLA was blended with the copolymer and the organoclay. (author)

  14. Aberrant right subclavian artery- suggested mechanism for esophageal foreign body impaction: Case report

    Directory of Open Access Journals (Sweden)

    Best Lael A

    2011-04-01

    Full Text Available Abstract Aberrant right subclavian artery (ARSA is asymptomatic in most cases. This variant anatomy can cause dysphagia in elderly patients. Impaction of foreign body in the esophagus is rarely the presenting symptom of ARSA. We present an eighty four years old patient who first presented with esophageal foreign body impaction and was diagnosed with an aberrant right subclavian artery compressing the esophagus just below the site of impaction. We assume that the exact place of impaction was not incidental and that a relative narrowing of the esophagus caused by the vascular anomaly is responsible for this specific presentation.

  15. Impact of Particle Size of Ceramic Granule Blends on Mechanical Strength and Porosity of 3D Printed Scaffolds

    Directory of Open Access Journals (Sweden)

    Sebastian Spath

    2015-07-01

    Full Text Available 3D printing is a promising method for the fabrication of scaffolds in the field of bone tissue engineering. To date, the mechanical strength of 3D printed ceramic scaffolds is not sufficient for a variety of applications in the reconstructive surgery. Mechanical strength is directly in relation with the porosity of the 3D printed scaffolds. The porosity is directly influenced by particle size and particle-size distribution of the raw material. To investigate this impact, a hydroxyapatite granule blend with a wide particle size distribution was fractioned by sieving. The specific fractions and bimodal mixtures of the sieved granule blend were used to 3D print specimens. It has been shown that an optimized arrangement of fractions with large and small particles can provide 3D printed specimens with good mechanical strength due to a higher packing density. An increase of mechanical strength can possibly expand the application area of 3D printed hydroxyapatite scaffolds.

  16. The Squiggle: A Digital Musical Instrument

    OpenAIRE

    Sheehan, Brian

    2004-01-01

    This paper discusses some of the issues pertaining to thedesign of digital musical instruments that are to effectively fillthe role of traditional instruments (i.e. those based on physicalsound production mechanisms). The design andimplementation of a musical instrument that addresses some ofthese issues, using scanned synthesis coupled to a "smart"physical system, is described.

  17. Radiological instrument

    International Nuclear Information System (INIS)

    Kronenberg, S.; McLaughlin, W.L.; Seibentritt, C.R. Jr.

    1986-01-01

    An instrument is described for measuring radiation, particularly nuclear radiation, comprising: a radiation sensitive structure pivoted toward one end and including a pair of elongated solid members contiguously joined together along their length dimensions and having a common planar interface therebetween. One of the pairs of members is comprised of radiochromic material whose index of refraction changes due to anomolous dispersion as a result of being exposed to nuclear radiation. The pair of members further has mutually different indices of refraction with the member having the larger index of refraction further being transparent for the passage of light and of energy therethrough; means located toward the other end of the structure for varying the angle of longitudinal elevation of the pair of members; means for generating and projecting a beam of light into one end of the member having the larger index of refraction. The beam of light is projected toward the planar interface where it is reflected out of the other end of the same member as a first output beam; means projecting a portion of the beam of light into one end of the member having the larger index of refraction where it traverses therethrough without reflection and out of the other end of the same member as a second output beam; and means adjacent the structure for receiving the first and second output beams, whereby a calibrated change in the angle of elevation of the structure between positions of equal intensity of the first and second output beams prior to and following exposure provides a measure of the radiation sensed due to a change of refraction of the radiochromic material

  18. Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

    NARCIS (Netherlands)

    Ageron, M.; Kooijman, P.

    2007-01-01

    A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion

  19. Instrumented Moles for Planetary Subsurface Regolith Studies

    Science.gov (United States)

    Richter, L. O.; Coste, P. A.; Grzesik, A.; Knollenberg, J.; Magnani, P.; Nadalini, R.; Re, E.; Romstedt, J.; Sohl, F.; Spohn, T.

    2006-12-01

    Soil-like materials, or regolith, on solar system objects provide a record of physical and/or chemical weathering processes on the object in question and as such possess significant scientific relevance for study by landed planetary missions. In the case of Mars, a complex interplay has been at work between impact gardening, aeolian as well as possibly fluvial processes. This resulted in regolith that is texturally as well as compositionally layered as hinted at by results from the Mars Exploration Rover (MER) missions which are capable of accessing shallow subsurface soils by wheel trenching. Significant subsurface soil access on Mars, i.e. to depths of a meter or more, remains to be accomplished on future missions. This has been one of the objectives of the unsuccessful Beagle 2 landed element of the ESA Mars Express mission having been equipped with the Planetary Underground Tool (PLUTO) subsurface soil sampling Mole system capable of self-penetration into regolith due to an internal electro-mechanical hammering mechanism. This lightweight device of less than 900 g mass was designed to repeatedly obtain and deliver to the lander regolith samples from depths down to 2 m which would have been analysed for organic matter and, specifically, organic carbon from potential extinct microbial activity. With funding from the ESA technology programme, an evolved Mole system - the Instrumented Mole System (IMS) - has now been developed to a readiness level of TRL 6. The IMS is to serve as a carrier for in situ instruments for measurements in planetary subsurface soils. This could complement or even eliminate the need to recover samples to the surface. The Engineering Model hardware having been developed within this effort is designed for accommodating a geophysical instrument package (Heat Flow and Physical Properties Package, HP3) that would be capable of measuring regolith physical properties and planetary heat flow. The chosen design encompasses a two-body Mole

  20. An Investigation of the Impact of Corporate Governance Mechanisms on Level of Corporate Risk Disclosure: Evidence from Kuwait

    Directory of Open Access Journals (Sweden)

    Bader Al-Shammari

    2014-06-01

    Full Text Available This study investigated the association between corporate governance mechanisms and corporate risk disclosure (CRD in the annual reports for a sample of 109 Kuwaiti listed non-financial companies in 2012. The study used a manual content analysis to measure risk disclosure by counting the number of risk-related sentences in annual reports. A multiple regression analysis was used to test the impact of board size, non-executive directors, percentage of family members on board, role duality, and audit committee on CRD. The quantity of risk disclosures in the Kuwaiti companies' annual reports was very limited. The results showed that the larger board size has a positive impact on CRD. However, the findings also indicated the existence of role duality lead to lower risk disclosure. Other corporate governance mechanisms did not explain variation in CRD.

  1. the impacts of auto-mechanic workshops on the environment of ...

    African Journals Online (AJOL)

    Aladesida

    The extents of groundwater and soil pollution arising from auto-mechanic ..... Conductivity is the ability of a solution to pass electric .... processes used at an auto-mechanic workshop, which ... Levels of Heavy Metals in Top Soils of Motor. Parks ...

  2. Impact of occupational mechanical exposures on risk of lateral and medial inguinal hernia requiring surgical repair

    DEFF Research Database (Denmark)

    Vad, Marie Vestergaard; Frost, Poul; Bay-Nielsen, Morten

    2012-01-01

    We undertook a register-based cohort study to evaluate exposure-response relations between cumulative occupational mechanical exposures, and risk of lateral and medial inguinal hernia repair.......We undertook a register-based cohort study to evaluate exposure-response relations between cumulative occupational mechanical exposures, and risk of lateral and medial inguinal hernia repair....

  3. Optical and mechanical excitation thermography for impact response in basalt-carbon hybrid fiber-reinforced composite laminates

    OpenAIRE

    Zhang, Hai; Sfarra, Stefano; Sarasini, Fabrizio; Ibarra-Castanedo, Clemente; Perilli, Stefano; Fernandes, Henrique; Duan, Yuxia; Peeters, Jeroen; Avelidis, Nicholas P; Maldague, Xavier

    2017-01-01

    Abstract: In this paper, optical and mechanical excitation thermography were used to investigate basalt fiber reinforced polymer (BFRP), carbon fiber reinforced polymer (CFRP) and basalt-carbon fiber hybrid specimens subjected to impact loading. Interestingly, two different hybrid structures including sandwich-like and intercalated stacking sequence were used. Pulsed phase thermography (PPT), principal component thermography (PCT) and partial least squares thermography (PLST) were used to pro...

  4. Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ageron, M. [CPPM-Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (France); Aguilar, J.A. [IFIC-Instituto de Fisica Corpuscular, Edificios Investigacion de Paterna, CSIC-Universitat de Valencia, Apdo. de Correos 22085, 46071 Valencia (Spain); Albert, A. [GRPHE-Groupe de Recherche en Physique des Hautes Energies, Universite de Haute Alsace, 61 Rue Albert Camus, 68093 Mulhouse Cedex (France); Ameli, F. [Dipartimento di Fisica dell' Universita ' La Sapienza' e Sezione INFN, P.le Aldo Moro 2, 00185 Roma (Italy); Anghinolfi, M. [Dipartimento di Fisica dell' Universita e Sezione INFN, Via Dodecaneso 33, 16146 Genova (Italy); Anton, G. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Anvar, S.; Ardellier-Desages, F. [DSM/DAPNIA-Direction des Sciences de la Matiere, Laboratoire de Recherche sur les lois Fondamentales de l' Univers, CEA Saclay, 91191 Gif-sur-Yvette Cedex (France); Aslanides, E.; Aubert, J.-J. [CPPM-Centre de Physique des Particules de Marseille, CNRS/IN2P3 et Universite de la Mediterranee, 163 Avenue de Luminy, Case 902, 13288 Marseille Cedex 9 (France); Auer, R. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany); Barbarito, E. [Dipartimento Interateneo di Fisica e Sezione INFN, Via E. Orabona 4, 70126 Bari (Italy); Basa, S. [LAM-Laboratoire d' Astrophysique de Marseille, CNRS/INSU et Universite de Provence, Traverse du Siphon-Les Trois Lucs, BP 8, 13012 Marseille Cedex 12 (France); Battaglieri, M. [Dipartimento di Fisica dell' Universita e Sezione INFN, Via Dodecaneso 33, 16146 Genova (Italy); Bazzotti, M.; Becherini, Y. [Dipartimento di Fisica dell' Universita e Sezione INFN, Viale Berti Pichat 6/2, 40127 Bologna (Italy)] (and others)

    2007-11-01

    A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented.

  5. Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

    International Nuclear Information System (INIS)

    Ageron, M.; Aguilar, J.A.; Albert, A.; Ameli, F.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardellier-Desages, F.; Aslanides, E.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Basa, S.; Battaglieri, M.; Bazzotti, M.; Becherini, Y.

    2007-01-01

    A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented

  6. Impact of mechanical bowel preparation in elective colorectal surgery: A meta-analysis.

    Science.gov (United States)

    Rollins, Katie E; Javanmard-Emamghissi, Hannah; Lobo, Dileep N

    2018-01-28

    To analyse the effect of mechanical bowel preparation vs no mechanical bowel preparation on outcome in patients undergoing elective colorectal surgery. Meta-analysis of randomised controlled trials and observational studies comparing adult patients receiving mechanical bowel preparation with those receiving no mechanical bowel preparation, subdivided into those receiving a single rectal enema and those who received no preparation at all prior to elective colorectal surgery. A total of 36 studies (23 randomised controlled trials and 13 observational studies) including 21568 patients undergoing elective colorectal surgery were included. When all studies were considered, mechanical bowel preparation was not associated with any significant difference in anastomotic leak rates (OR = 0.90, 95%CI: 0.74 to 1.10, P = 0.32), surgical site infection (OR = 0.99, 95%CI: 0.80 to 1.24, P = 0.96), intra-abdominal collection (OR = 0.86, 95%CI: 0.63 to 1.17, P = 0.34), mortality (OR = 0.85, 95%CI: 0.57 to 1.27, P = 0.43), reoperation (OR = 0.91, 95%CI: 0.75 to 1.12, P = 0.38) or hospital length of stay (overall mean difference 0.11 d, 95%CI: -0.51 to 0.73, P = 0.72), when compared with no mechanical bowel preparation, nor when evidence from just randomized controlled trials was analysed. A sub-analysis of mechanical bowel preparation vs absolutely no preparation or a single rectal enema similarly revealed no differences in clinical outcome measures. In the most comprehensive meta-analysis of mechanical bowel preparation in elective colorectal surgery to date, this study has suggested that the use of mechanical bowel preparation does not affect the incidence of postoperative complications when compared with no preparation. Hence, mechanical bowel preparation should not be administered routinely prior to elective colorectal surgery.

  7. Study to determine the reliability and validity of a needs-assessment instrument used within the mechanical maintenance field of the nuclear electrical-generating industry

    International Nuclear Information System (INIS)

    Russell, L.O.

    1982-01-01

    This study was to determine if task parameter ratings provided by nuclear power plant maintenance mechanics assessed the true task frequency, criticality, and difficulty. This was to measure the data's usefulness as a training needs assessment indicator. A questionnaire entitled Job Task Questionnaire for Maintenance Mechanics was developed and used to collect data from job incumbents. Development was based on plant visits and incumbent interviews. Duties, tasks, parameters, and scales were then compiled to form the questionnaire. The questionnaire was then pilot tested. A random sample was selected from the national population of nuclear power plant maintenance mechanics. This resulted in a sample which was stratified across the job title and random within the job title. The descriptive analysis did not tend to indicate that the mean value of each task parameter provided a true or valid value. The overall conclusion drawn from the data analysis was that the ratings did not provide a substantially valid or reliable indication on which to base task training needs

  8. Impact 2.0 : New Mechanisms for Linking Research and Policy ...

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

    At the same time, interactive web-based services and applications, including wikis and social networking sites are ... had a significant impact on people's social lives and political action, as well as industries like advertising and the media.

  9. Impact of mechanical- and maintenance-induced failures of main reactor coolant pump seals on plant safety

    International Nuclear Information System (INIS)

    Azarm, M.A.; Boccio, J.L.; Mitra, S.

    1985-12-01

    This document presents an investigation of the safety impact resulting from mechanical- and maintenance-induced reactor coolant pump (RCP) seal failures in nuclear power plants. A data survey of the pump seal failures for existing nuclear power plants in the US from several available sources was performed. The annual frequency of pump seal failures in a nuclear power plant was estimated based on the concept of hazard rate and dependency evaluation. The conditional probability of various sizes of leak rates given seal failures was then evaluated. The safety impact of RCP seal failures, in terms of contribution to plant core-melt frequency, was also evaluated for three nuclear power plants. For leak rates below the normal makeup capacity and the impact of plant safety were discussed qualitatively, whereas for leak rates beyond the normal make up capacity, formal PRA methodologies were applied. 22 refs., 17 figs., 19 tabs

  10. Numerical simulations of mechanical and ignition-deflagration responses for PBXs under low-to-medium-level velocity impact loading.

    Science.gov (United States)

    Yang, Kun; Wu, Yanqing; Huang, Fenglei; Li, Ming

    2017-09-05

    An effective computational model is required to accurately predict the dynamic responses in accidental initiations of explosives. The present work uses a series of two-dimensional mechanical-chemical simulations performed via a hydrodynamic-code, DREXH-2D, to efficiently describe the mechanical and ignition-deflagration responses of cased cylindrical polymer-bonded explosives (PBXs) undergoing a low-to-medium-level impact (70-350m/s) in longitudinal direction. The ignition response was predicted based on an ignition criterion of effective plastic work. Slow burning and its growth to deflagration were described through a pressure-dependent reaction rate equation. The extreme value of effective plastic work was found to be useful to determine the ignition threshold velocity for PBXs. For low-level velocity impact, the incident stress wave reflection from lateral surfaces contributed to the formation of ignition regions. After the ignition, the deflagration was induced in the medium-level impact, and its violence was related to the shock strength. However, the low-strength stress wave only induced reaction at local regions, and sequent burning was no longer sensitive to the strength of incident wave. The predicted pressure and temperature results of PBXs were consistent with the medium-level impact tests performed by China Academy of Engineering Physics. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Effect of mechanical alloying atmosphere on the microstructure and Charpy impact properties of an ODS ferritic steel

    International Nuclear Information System (INIS)

    Oksiuta, Z.; Baluc, N.

    2009-01-01

    Two types of oxide dispersion strengthened (ODS) ferritic steels, with the composition of Fe-14Cr-2W-0.3Ti-0.3Y 2 O 3 (in weight percent), have been produced by mechanically alloying elemental powders of Fe, Cr, W, and Ti with Y 2 O 3 particles either in argon atmosphere or in hydrogen atmosphere, degassing at various temperatures, and compacting the mechanically alloyed powders by hot isostatic pressing. It was found in particular that mechanical alloying in hydrogen yields a significant reduction in oxygen content in the materials, a lower dislocation density, and a strong improvement in the fast fracture properties of the ODS ferritic steels, as measured by Charpy impact tests.

  12. AN INVESTIGATION OF THE IMPACT OF IMPURITIES ON THE MECHANICAL PROPERTIES OF RECYCLED PVC EXTRUSION PIPES

    OpenAIRE

    Adamu Alhaji Umar; Raji Olalere Fatai

    2007-01-01

    This work studied the effect of using recycled scraps in the production of rigid PVC extrusion pipe. Different formulations with varied percentages of scraps were extruded and various tests carried out on the sample specimen to determine their corresponding mechanical properties. It was finally discovered that among the two sources of scraps, the in-house scraps contained less impurities and blending about 10% of it with virgin PVC material in the production gave improved mechanical propertie...

  13. Introduction to instrumentation and measurements

    CERN Document Server

    Northrop, Robert B

    2014-01-01

    Weighing in on the growth of innovative technologies, the adoption of new standards, and the lack of educational development as it relates to current and emerging applications, the third edition of Introduction to Instrumentation and Measurements uses the authors' 40 years of teaching experience to expound on the theory, science, and art of modern instrumentation and measurements (I&M). What's New in This Edition: This edition includes material on modern integrated circuit (IC) and photonic sensors, micro-electro-mechanical (MEM) and nano-electro-mechanical (NEM) sensors, chemical and radiation sensors, signal conditioning, noise, data interfaces, and basic digital signal processing (DSP), and upgrades every chapter with the latest advancements. It contains new material on the designs of micro-electro-mechanical (MEMS) sensors, adds two new chapters on wireless instrumentation and microsensors, and incorporates extensive biomedical examples and problems. Containing 13 chapters, this third edition: Describ...

  14. Beam Instrumentation and Diagnostics

    CERN Document Server

    Strehl, Peter

    2006-01-01

    This treatise covers all aspects of the design and the daily operations of a beam diagnostic system for a large particle accelerator. A very interdisciplinary field, it involves contributions from physicists, electrical and mechanical engineers and computer experts alike so as to satisfy the ever-increasing demands for beam parameter variability for a vast range of operation modi and particles. The author draws upon 40 years of research and work, most of them spent as the head of the beam diagnostics group at GSI. He has illustrated the more theoretical aspects with many real-life examples that will provide beam instrumentation designers with ideas and tools for their work.

  15. Liquid Impact Erosion Mechanism and Theoretical Stress Analysis in TiN-Coated Turbine Blade

    International Nuclear Information System (INIS)

    Lee, M. K.; Kim, W. W.; Kim, S. J.; Rhee, C. K.; Kim, Y. S.

    2000-01-01

    Coating of TiN film was done by reactive magnetron sputter ion plating to improve the liquid impact erosion resistance of steam turbine blade materials, 12Cr steel and Stellite 6B, for nuclear power plant application. TiN coated blade materials were initially deformed with depressions due to plastic deformation of the ductile substrate. The increase in the curvature in the depressions induced stress concentration with increasing number of impacts, followed by circumferential fracture of the TiN coating due to the circular propagation of cracks. The liquid impact erosion resistance of the blade materials was greatly improved by TiN coating done with the optimum ion plating condition. Damage decreased with increasing TiN coating thickness. According to the theoretical analysis of stresses generated by liquid impact, TiN coating alleviated the impact stress of 12Cr steel and Stellite 6B due to stress attenuation and stress wave reactions such as reflection and transmission at the coating substrate interface

  16. The instrumental resolution of a moire extensometer in light of its recent automatisation

    Czech Academy of Sciences Publication Activity Database

    Rowberry, Matthew David; Kriegner, D.; Holý, V.; Frontera, C.; Llull, M.; Olejník, Kamil; Martí, Xavier

    2016-01-01

    Roč. 91, SEP (2016), s. 258-265 ISSN 0263-2241 R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985891 ; RVO:68378271 Keywords : geological discontinuity monitoring * mechanical extensometer * moire patterns * instrumental resolution Subject RIV: JB - Sensors, Measurment, Regulation; BM - Solid Matter Physics ; Magnetism (FZU-D) Impact factor: 2.359, year: 2016

  17. High impact polystyrene (HIPS). Predicting its molecular, morphological and mechanical properties

    International Nuclear Information System (INIS)

    Luciani, C; Estenoz, D; Morales, G; Meira, G

    2004-01-01

    A mathematical model that is able to predict the molecular and morphological structure of high impact polystyrene (HIPS) and the Fluidity Index (MFI) is presented. The model is divided into two parts: a) the estimation of the material's molecular and morphological properties, simulating the polymerization process in discontinuous mass based on the recipe and the conditions of synthesis; and b) the prediction of rheological variables (viscosity at low deformation speeds and relaxation time), and of the MFI, based on average molecular and morphological variables. The model also combines with empirical correlations proposed in the literature [1] in order to estimate impact strength (IS). The predictions for a), b) and impact strength were co-validated by independent data and resulted in a good fit (CW)

  18. Geological history and its impact on the rock mechanics properties of the Olkiluoto site

    International Nuclear Information System (INIS)

    Hudson, J.A.; Cosgrove, J.W.

    2006-03-01

    This report is one of three documents with background information for supporting the development of Posiva's future rock mechanics programme. The other two reports are a summary of all the rock mechanics work completed for Posiva before 2005 (Posiva Working Report) and a technical audit of the numerical modeling work that has been conducted previously for Posiva (REC Memo). The purpose of this report is to establish the extent to which the mechanical properties of the rocks at the Olkiluoto site can be estimated from a knowledge of the geological environment. The main information required for rock mechanics studies of the site is a knowledge of the prevailing stress state, the properties of the intact rock, and the properties of the fractures at all scales - from sizes that could form blocks in the tunnel roof up to the major brittle deformation zones that could be influence the location of the ONKALO and the subsequent repository. Thus, the summary of the geological history in Chapter 2 concentrates on these features and we summarise the ductile and brittle deformational tectonic history of the site, with emphasis on the inferred stress states causing the deformations. Then, in Chapter 3, the rock stress, the hierarchy of brittle fracturing, the fracture properties and the mechanical properties of the rock mass are considered in the light of the geological environment. These features provide the baseline knowledge of the host rock from which the logic of the future rock mechanics programme can be developed, based on: the bedrock model; the site investigation results; the requirements for generating the site descriptive model; the prediction-outcome ONKALO studies; and numerically modeling the effects of excavation for design and safety analysis. The implications of this study for the future rock mechanics work are outlined in Chapter 4 with emphasis on the key features for modeling. (orig.)

  19. Quantum optics and nano-optics teaching laboratory for the undergraduate curriculum: teaching quantum mechanics and nano-physics with photon counting instrumentation

    Science.gov (United States)

    Lukishova, Svetlana G.

    2017-08-01

    At the Institute of Optics, University of Rochester (UR), we have adapted to the main challenge (the lack of space in the curriculum) by developing a series of modular 3-hour experiments and 20-min-demonstrations based on technical elective, 4-credit-hour laboratory course "Quantum Optics and Nano-Optics Laboratory" (OPT 253/OPT453/PHY434), that were incorporated into a number of required courses ranging from freshman to senior level. Rochester Monroe Community College (MCC) students also benefited from this facility that was supported by four NSF grants. MCC students carried out two 3-hour labs on photon quantum mechanics at the UR. Since 2006, total 566 students passed through the labs with lab reports submission (including 144 MCC students) and more than 250 students through lab demonstrations. In basic class OPT 253, four teaching labs were prepared on generation and characterization of entangled and single (antibunched) photons demonstrating the laws of quantum mechanics: (1) entanglement and Bell's inequalities, (2) single-photon interference (Young's double slit experiment and Mach-Zehnder interferometer), (3) confocal microscope imaging of single-emitter (colloidal nanocrystal quantum dots and NV-center nanodiamonds) fluorescence within photonic (liquid crystal photonic bandgap microcavities) or plasmonic (gold bowtie nanoantennas) nanostructures, (4) Hanbury Brown and Twiss setup. Fluorescence antibunching from nanoemitters. Students also carried out measurements of nanodiamond topography using atomic force microscopy and prepared photonic bandgap materials from cholesteric liquid crystals. Manuals, student reports, presentations, lecture materials and quizzes, as well as some NSF grants' reports are placed on a website http://www.optics.rochester.edu/workgroups/lukishova/QuantumOpticsLab/ . In 2011 UR hosted 6 professors from different US universities in three-days training of these experiments participating in the Immersion Program of the Advanced

  20. An investigation into the impact of cryogenic environment on mechanical stresses in FRP composites

    Science.gov (United States)

    Fifo, O.; Basu, B.

    2015-07-01

    Fibre reinforced polymer (FRP) composites are fast becoming a highly utilised engineering material for high performance applications due to their light weight and high strength. Carbon fibre and other high strength fibres are commonly used in design of aerospace structures, wind turbine blades, etc. and potentially for propellant tanks of launch vehicles. For the aforementioned fields of application, stability of the material is essential over a wide range of temperature particularly for structures in hostile environments. Many studies have been conducted, experimentally, over the last decade to investigate the mechanical behaviour of FRP materials at varying subzero temperature. Likewise, tests on aging and cycling effect (room to low temperature) on the mechanical response of FRP have been reported. However, a relatively lesser focused area has been the mechanical behaviour of FRP composites under cryogenic environment. This article reports a finite element method of investigating the changes in the mechanical characteristics of an FRP material when temperature based analysis falls below zero. The simulated tests are carried out using a finite element package with close material properties used in the cited literatures. Tensile test was conducted and the results indicate that the mechanical responses agree with those reported in the literature sited.

  1. Impact of mechanical heterogeneity on joint density in a welded ignimbrite

    Science.gov (United States)

    Soden, A. M.; Lunn, R. J.; Shipton, Z. K.

    2016-08-01

    Joints are conduits for groundwater, hydrocarbons and hydrothermal fluids. Robust fluid flow models rely on accurate characterisation of joint networks, in particular joint density. It is generally assumed that the predominant factor controlling joint density in layered stratigraphy is the thickness of the mechanical layer where the joints occur. Mechanical heterogeneity within the layer is considered a lesser influence on joint formation. We analysed the frequency and distribution of joints within a single 12-m thick ignimbrite layer to identify the controls on joint geometry and distribution. The observed joint distribution is not related to the thickness of the ignimbrite layer. Rather, joint initiation, propagation and termination are controlled by the shape, spatial distribution and mechanical properties of fiamme, which are present within the ignimbrite. The observations and analysis presented here demonstrate that models of joint distribution, particularly in thicker layers, that do not fully account for mechanical heterogeneity are likely to underestimate joint density, the spatial variability of joint distribution and the complex joint geometries that result. Consequently, we recommend that characterisation of a layer's compositional and material properties improves predictions of subsurface joint density in rock layers that are mechanically heterogeneous.

  2. Acclimation of mechanical and hydraulic functions in trees:Impact of the thigmomorphogenetic process

    Directory of Open Access Journals (Sweden)

    Eric eBadel

    2015-04-01

    Full Text Available The secondary xylem (wood of trees mediates several functions including water transport and storage, mechanical support and storage of photosynthates. The optimal structures for each of these functions will most likely differ. The complex structure and function of xylem could lead to trade-offs between conductive efficiency, resistance to embolism and mechanical strength needed to count for mechanical loading due to gravity and wind. This has been referred to as the trade-off triangle, with the different optimal solutions to the structure/function problems depending on the environmental constraints as well as taxonomic histories. Thus, the optimisation of each function will lead to drastically different anatomical structures. Trees are able to acclimate the internal structure of their trunk and branches according to the stress they experience. These acclimations lead to specific structures that favour the efficiency or the safety of one function but can be antagonistic with other functions. Currently, there are no means to predict the way a tree will acclimate or optimize its internal structure in support of its various functions under differing environmental conditions. In this review, we will focus on the acclimation of xylem anatomy and its resulting mechanical and hydraulic functions to recurrent mechanical strain that usually result from wind-induced thigmomorphogenesis with a special focus on the construction cost and the possible trade-off between wood functions.

  3. Analysis of institutional mechanisms that support community response to impacts of floods in the middle-zambezi river basin, Zimbabwe

    Science.gov (United States)

    Muhonda, P.; Mabiza, C.; Makurira, H.; Kujinga, K.; Nhapi, I.; Goldin, J.; Mashauri, D. A.

    In recent years, the frequency of occurrence of floods has increased in Southern Africa. An increase in the frequency of extreme events is partly attributed to climate change. Floods negatively impact on livelihoods, especially those classified as poor, mainly by reducing livelihood options and also contributing to reduced crop yields. In response to these climatic events, governments within Southern Africa have formulated policies which try to mitigate the impacts of floods. Floods can be deadly, often occurring at short notice, lasting for short periods, and causing widespread damage to infrastructure. This study analysed institutional mechanisms in Mbire District of Zimbabwe which aim at mitigating the impact of floods. The study used both quantitative (i.e. questionnaires) and qualitative (i.e. key informant interviews, focus group discussions and observations) data collection methods. Secondary data such as policy and legislation documents and operational manuals of organisations that support communities affected by disasters were reviewed. Qualitative data was analysed using the thematic approach and social network analysis using UCINET 6. Quantitative data were analysed using SPSS 19.0. The study found out that there exists institutional framework that has been developed at the national and local level to support communities in the study area in response to the impacts of floods. This is supported by various pieces of legislation that are housed in different government departments. However, the existing institutional framework does not effectively strengthen disaster management mechanisms at the local level. Lack of financial resources and appropriate training and skills to undertake flood management activities reduce the capacity of communities and disaster management organisations to effectively mitigate the impacts of floods. The study also found that there are inadequate hydro-meteorological stations to enable accurate forecasts. Even in those cases

  4. Flow-induced solidification of high-impact polypropylene copolymer compositions : morphological and mechanical effects

    NARCIS (Netherlands)

    Drongelen, van M.; Gahleitner, M.; Spoelstra, A.B.; Govaert, L.E.; Peters, G.W.M.

    2015-01-01

    Polypropylene-based impact copolymers are a complex composition of matrix material, a dispersed phase and many optional modifiers. The final heterophasic morphology of such systems is influenced significantly by the processing step, adding an additional level of complexity to understanding the

  5. Impact of supersonic and subsonic aircraft on ozone: Including heterogeneous chemical reaction mechanisms

    International Nuclear Information System (INIS)

    Kinnison, D.E.; Wuebbles, D.J.

    1992-01-01

    Preliminary calculations suggest that heterogeneous reactions are important in calculating the impact on ozone from emissions of trace gases from aircraft fleets. In this study, three heterogeneous chemical processes that occur on background sulfuric acid aerosols are included and their effects on O 3 , NO x , Cl x , HCl, N 2 O 5 , ClONO 2 are calculated

  6. GIANT IMPACT: AN EFFICIENT MECHANISM FOR THE DEVOLATILIZATION OF SUPER-EARTHS

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shang-Fei [Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064 (United States); Hori, Yasunori; Lin, D. N. C. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Asphaug, Erik, E-mail: sliu26@ucsc.edu, E-mail: yahori@ucsc.edu, E-mail: lin@ucolick.org, E-mail: easphaug@asu.edu [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States)

    2015-10-20

    Mini-Neptunes and volatile-poor super-Earths coexist on adjacent orbits in proximity to host stars such as Kepler-36 and Kepler-11. Several post-formation processes have been proposed for explaining the origin of the compositional diversity between neighboring planets: mass loss via stellar XUV irradiation, degassing of accreted material, and in situ accumulation of the disk gas. Close-in planets are also likely to experience giant impacts during the advanced stage of planet formation. This study examines the possibility of transforming volatile-rich super-Earths/mini-Neptunes into volatile-depleted super-Earths through giant impacts. We present the results of three-dimensional hydrodynamic simulations of giant impacts in the accretionary and disruptive regimes. Target planets are modeled with a three-layered structure composed of an iron core, silicate mantle, and hydrogen/helium envelope. In the disruptive case, the giant impact can remove most of the H/He atmosphere immediately and homogenize the refractory material in the planetary interior. In the accretionary case, the planet is able to retain more than half of the original gaseous envelope, while a compositional gradient suppresses efficient heat transfer as the planetary interior undergoes double-diffusive convection. After the giant impact, a hot and inflated planet cools and contracts slowly. The extended atmosphere enhances the mass loss via both a Parker wind induced by thermal pressure and hydrodynamic escape driven by the stellar XUV irradiation. As a result, the entire gaseous envelope is expected to be lost due to the combination of those processes in both cases. Based on our results, we propose that Kepler-36b may have been significantly devolatilized by giant impacts, while a substantial fraction of Kepler-36c’s atmosphere may remain intact. Furthermore, the stochastic nature of giant impacts may account for the observed large dispersion in the mass–radius relationship of close-in super

  7. Facts and Fiction: The Impact of Hypothermia on Molecular Mechanisms following Major Challenge

    Directory of Open Access Journals (Sweden)

    Michael Frink

    2012-01-01

    Full Text Available Numerous multiple trauma and surgical patients suffer from accidental hypothermia. While induced hypothermia is commonly used in elective cardiac surgery due to its protective effects, accidental hypothermia is associated with increased posttraumatic complications and even mortality in severely injured patients. This paper focuses on protective molecular mechanisms of hypothermia on apoptosis and the posttraumatic immune response. Although information regarding severe trauma is limited, there is evidence that induced hypothermia may have beneficial effects on the posttraumatic immune response as well as apoptosis in animal studies and certain clinical situations. However, more profound knowledge of mechanisms is necessary before randomized clinical trials in trauma patients can be initiated.

  8. Effects of curing type, silica fume fineness, and fiber length on the mechanical properties and impact resistance of UHPFRC

    Directory of Open Access Journals (Sweden)

    Hasan Şahan Arel

    Full Text Available The effects of silica fume fineness and fiber aspect ratio on the compressive strength and impact resistance of ultra high-performance fiber-reinforced concrete (UHPFRC are investigated experimentally. To this end, UHPFRC mixtures are manufactured by combining silica fumes with different fineness (specific surface areas: 17,200, 20,000, and 27,600 m2/kg and hooked-end steel fibers with various aspect ratios (lengths: 8, 13, and 16 mm. The samples are subjected to standard curing, steam curing, and hot-water curing. Compressive strength tests are conducted after 7-, 28-, 56-, and 90-day curing periods, and an impact resistance experiment is performed after the 90th day. A steam-cured mixture of silica fumes with a specific surface area of 27,600 m2/kg and 16-mm-long fibers produce better results than the other mixtures in terms of mechanical properties. Moreover, impact resistance increases with the fiber aspect ratio. Keywords: Curing, Fineness, UHPFRC, Mechanical properties, Fiber

  9. Dan PERJU (1935 – 2016 Professor Emeritus Ph.D. Engineer, Corresponding member of the Academy of Technical Sciences in Romania Representative of the Timişoara School of Mechanisms, Fine Mechanics and Measuring Instruments

    Directory of Open Access Journals (Sweden)

    Erwin-Christian Lovasz

    2017-12-01

    Full Text Available Professor Dan Perju was born on 15 December 1935 in Chişinău - Republic of Moldova, as the son of a family of teachers. He graduated from the Faculty of Mechanical Engineering of the Polytechnic Institute "Traian Vuia" in Timişoara, section Hydraulic Machines (1957-1962, being Head of Promotion. After the graduation of the faculty and until the eternity, Professor Dan Perju has gone through all stages of an exceptional academic career, gaining a national and international academic recognition. His entire teaching and scientific activity was done faithfully within the Department of Machine Design and Mechanisms (OMM of the Mechanical Engineering Faculty of the Politehnica University of Timişoara (UPT, now the Department of Mechatronics.

  10. Impact of mechanized logging operations on wet and dry soils of ...

    African Journals Online (AJOL)

    Mechanization of timber harvesting operations in Tanzania involves use of machinery such as feller bunchers, skidders and tractors which are generally heavy in weight ranging from 12 to 16 tones in unloaded state. The movements of these machines induce soil compaction owing to the exerted normal pressure, vibrations ...

  11. Impact of Conflict Management Strategies on the Generation Mechanism of Miners' Unsafe Behavior Tendency

    Science.gov (United States)

    Li, Ji-Zu; Zhang, Ya-Ping; Liu, Xiao-Guang; Liu, Yao-Long; Wang, Tian-Ri

    2017-01-01

    In this paper, we examine the relationship between the generation mechanism of miners' unsafe behavior tendency and conflict management strategies, including cooperative conflict management strategy, competitive conflict management strategy and avoidant conflict management strategy. Miners from 3 collieries in Shanxi province completed a…

  12. Environmental effects of large impacts on the earth; relation to extinction mechanisms

    Science.gov (United States)

    Okeefe, John D.; Ahrens, Thomas J.; Koschny, Detlef

    1988-01-01

    Since Alvarez et al., discovered a worldwide approx. cm-thick layer of fine sediments laden with platinum group elements in approximately chondritic proportions exactly at the Cretaceous-Tertiary (C-T) boundary, and proposed bolide-impact as triggering mass extinctions, many have studied this hypothesis and the layer itself with its associated spherules and shocked quartz. At issue is whether the mass extinctions, and this horizon has an impact versus volcanic origin. A critical feature of the Alvarez hypothesis is the suggestion that the bolide or possibly a shower of objects delivered to the earth approx. 0.6 x 10 to the 18th power g of material which resulted in aerosol-sized ejecta such that global insolation was drastically reduced for significant periods. Such an event would lower temperatures on continents and halt photosynthesis in the upper 200 m of th eocean. The latter would strangle the marine food chain and thus produce the major marine faunal extinctions which mark the C-T boundary. Crucial issues examined include: What are the dynamics of atmospheric flow occurring upon impact of a large bolide with the earth; What is the size distributions of the very fine impact ejecta and how do these compare to the models of ejecta which are used to model the earth's radiative thermal balance. The flow field due to passage of a 10 km diameter bolide through an exponential atmosphere and the interaction of the gas flow and bolide with the solid ear was calculated. The CO2 released upon impact onto shallow marine carbonate sections was modeled and found that the mass of CO2 released exceeds the present 10 to the 18th power g CO2 budget of the earth's atmosphere by several times. Using the calculations of Kasting and Toon it was found that to compute the temperature rise of the earth's surface as a function of CO2 content, it was found that sudden and prolonged global increases are induced from impact of 20 to 50 km radius projectiles and propose that sudden

  13. Assessing the Impact of Mechanical Damage on Full-Thickness Porcine and Human Skin Using an In Vitro Approach

    Directory of Open Access Journals (Sweden)

    Hinda Dabboue

    2015-01-01

    Full Text Available For most xenobiotics, the rates of percutaneous absorption are limited by diffusion through the horny layer of skin. However, percutaneous absorption of chemicals may seriously increase when the skin is damaged. The aim of this work was to develop an in vitro representative model of mechanically damaged skins. The epidermal barrier was examined following exposure to a razor, a rotating brush, and a microneedle system in comparison to tape-stripping which acted as a reference. Excised full-thickness skins were mounted on a diffusion chamber in order to evaluate the effect of injuries and to mimic physiological conditions. The transepidermal water loss (TEWL was greatly increased when the barrier function was compromised. Measurements were made for all the damaged biopsies and observed histologically by microscopy. On human and porcine skins, the tape-stripping application (0 to 40 times showed a proportional increase in TEWL which highlights the destruction of the stratum corneum. Similar results were obtained for all cosmetic instruments. This is reflected in our study by the nonsignificant difference of the mean TEWL scores between 30 strips and mechanical damage. For a specific appreciation, damaged skins were then selected to qualitatively evaluate the absorption of a chlorogenic acid solution using fluorescence microscopy.

  14. Multiaxial mechanical response and constitutive modeling of esophageal tissues: Impact on esophageal tissue engineering.

    Science.gov (United States)

    Sommer, Gerhard; Schriefl, Andreas; Zeindlinger, Georg; Katzensteiner, Andreas; Ainödhofer, Herwig; Saxena, Amulya; Holzapfel, Gerhard A

    2013-12-01

    Congenital defects of the esophagus are relatively frequent, with 1 out of 2500 babies suffering from such a defect. A new method of treatment by implanting tissue engineered esophagi into newborns is currently being developed and tested using ovine esophagi. For the reconstruction of the biological function of native tissues with engineered esophagi, their cellular structure as well as their mechanical properties must be considered. Since very limited mechanical and structural data for the esophagus are available, the aim of this study was to investigate the multiaxial mechanical behavior of the ovine esophagus and the underlying microstructure. Therefore, uniaxial tensile, biaxial tensile and extension-inflation tests on esophagi were performed. The underlying microstructure was examined in stained histological sections through standard optical microscopy techniques. Moreover, the uniaxial ultimate tensile strength and residual deformations of the tissue were determined. Both the mucosa-submucosa and the muscle layers showed nonlinear and anisotropic mechanical behavior during uniaxial, biaxial and inflation testing. Cyclical inflation of the intact esophageal tube caused marked softening of the passive esophagi in the circumferential direction. The rupture strength of the mucosa-submucosa layer was much higher than that of the muscle layer. Overall, the ovine esophagus showed a heterogeneous and anisotropic behavior with different mechanical properties for the individual layers. The intact and layer-specific multiaxial properties were characterized using a well-known three-dimensional microstructurally based strain-energy function. This novel and complete set of data serves the basis for a better understanding of tissue remodeling in diseased esophagi and can be used to perform computer simulations of surgical interventions or medical-device applications. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Comparison of quasistatic to impact mechanical properties of multiwall carbon nanotube/polycarbonate composites

    Energy Technology Data Exchange (ETDEWEB)

    Brühwiler, Paul A.; Barbezat, Michel; Necola, Adly; Kohls, Doug J.; Bunk, Oliver; Schaefer, Dale W.; Pötschke, Petra (PSI); (EMMPA); (UCIN); (Leibniz)

    2010-10-22

    We report the quasistatic tensile and impact penetration properties (falling dart test) of injection-molded polycarbonate samples, as a function of multiwall carbon nanotube (MWNT) concentration (0.0-2.5%). The MWNT were incorporated by dilution of a commercial MWNT/polycarbonate masterbatch. The stiffness and quasistatic yield strength of the composites increased approximately linearly with MWNT concentration in all measurements. The energy absorbed in fracture was, however, a negative function of the MWNT concentration, and exhibited different dependencies in quasistatic and impact tests. Small-angle x-ray scattering (SAXS) showed that the dispersion of the MWNT was similar at all concentrations. The negative effects on energy absorption are attributed to agglomerates remaining in the samples, which were observed in optical microscopy and SAXS. Overall, there was a good correspondence between static and dynamic energy absorption.

  16. The Physics of Protoplanetesimal Dust Agglomerates. IX. Mechanical Properties of Dust Aggregates Probed by a Solid-projectile Impact

    Science.gov (United States)

    Katsuragi, Hiroaki; Blum, Jürgen

    2017-12-01

    Dynamic characterization of mechanical properties of dust aggregates has been one of the most important problems to quantitatively discuss the dust growth in protoplanetary disks. We experimentally investigate the dynamic properties of dust aggregates by low-speed (≤slant 3.2 m s-1) impacts of solid projectiles. Spherical impactors made of glass, steel, or lead are dropped onto a dust aggregate with a packing fraction of ϕ = 0.35 under vacuum conditions. The impact results in cratering or fragmentation of the dust aggregate, depending on the impact energy. The crater shape can be approximated by a spherical segment and no ejecta are observed. To understand the underlying physics of impacts into dust aggregates, the motion of the solid projectile is acquired by a high-speed camera. Using the obtained position data of the impactor, we analyze the drag-force law and dynamic pressure induced by the impact. We find that there are two characteristic strengths. One is defined by the ratio between impact energy and crater volume and is ≃120 kPa. The other strength indicates the fragmentation threshold of dynamic pressure and is ≃10 kPa. The former characterizes the apparent plastic deformation and is consistent with the drag force responsible for impactor deceleration. The latter corresponds to the dynamic tensile strength to create cracks. Using these results, a simple model for the compaction and fragmentation threshold of dust aggregates is proposed. In addition, the comparison of drag-force laws for dust aggregates and loose granular matter reveals the similarities and differences between the two materials.

  17. Exploring the mechanisms of vehicle front-end shape on pedestrian head injuries caused by ground impact.

    Science.gov (United States)

    Yin, Sha; Li, Jiani; Xu, Jun

    2017-09-01

    In pedestrian-vehicle accidents, pedestrians typically suffer from secondary impact with the ground after the primary contact with vehicles. However, information about the fundamental mechanism of pedestrian head injury from ground impact remains minimal, thereby hindering further improvement in pedestrian safety. This study addresses this issue by using multi-body modeling and computation to investigate the influence of vehicle front-end shape on pedestrian safety. Accordingly, a simulation matrix is constructed to vary bonnet leading-edge height, bonnet length, bonnet angle, and windshield angle. Subsequently, a set of 315 pedestrian-vehicle crash simulations are conducted using the multi-body simulation software MADYMO. Three vehicle velocities, i.e., 20, 30, and 40km/h, are set as the scenarios. Results show that the top governing factor is bonnet leading-edge height. The posture and head injury at the instant of head ground impact vary dramatically with increasing height because of the significant rise of the body bending point and the movement of the collision point. The bonnet angle is the second dominant factor that affects head-ground injury, followed by bonnet length and windshield angle. The results may elucidate one of the critical barriers to understanding head injury caused by ground impact and provide a solid theoretical guideline for considering pedestrian safety in vehicle design. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Corporate Governance in Banks and its Impact on Risk and Performance: Review of Literature on the Selected Governance Mechanisms

    Directory of Open Access Journals (Sweden)

    Himaj Shkendije

    2014-09-01

    Full Text Available Corporate governance is viewed as an important, essential, and most significant factor for well-functioning of firms. Recent academic work and policy analyses have given insight into the governance problems in banks exposed to the financial crisis and suggest possible solutions. This paper begins by explaining the importance of corporate governance and its impact on risk taking and bank performance based on the theoretical background relevant to the corporate governance of banks. I combine the literature that looks at three areas of governance: ownership structure; board structure; and risk management, with the literature on risk-taking and performance effects in order to better assess the weight of the impact that these governance mechanisms have on both performance and risk. The paper concludes by highlighting the areas where further research is needed.

  19. Enhanced mechanical behaviors of gradient nano-grained austenite stainless steel by means of ultrasonic impact treatment

    Directory of Open Access Journals (Sweden)

    Xinjun Yang

    Full Text Available The gradient nano-grained (GNG structure was formed on the top layer of AISI 304 in the presence of coarse grains (CG by means of ultrasonic impact treatment (UIT. The impact velocity was 5 m/s and the coverage changed from 3000% to 9000% in order to obtain the microstructure GNG/CG materials. The tensile test and small punch test (SPT were further carried out in order to investigate the mechanical behaviors of the GNG/CG 304 at the different stress states. The results indicated that the yield strength of GNG/CG 304 obtained by tensile test and SPT increased at the small expense of ductility. The stress triaxiality T played an important role in the deformation behavior of GNG/CG 304. An increased T-value in the region of biaxial stretching of small punch specimen (T = 2/3 led to an improved ductility compared with that noted in the case of uniaxial tensile specimen. The strain rate sensitivity m of GNG/CG 304 was 0.0468 that was estimated to be 25-fold greater than the coarse material. The yield strength of GNG/CG 304 at 400 °C was 1.6-fold greater than the coarse material at ambient temperature due to the thermal stability of the GNG layer. Thus, the GNG structure could improve the comprehensive mechanical performances of AISI 304 with a balance of strength and ductility. Keywords: GNG structure, Mechanical behaviors, Small punch test, Ultrasonic impact treatment, Austenite stainless steel

  20. Impact of Desalination on Physical and Mechanical Properties of Lanzhou Loess

    Science.gov (United States)

    Bing, Hui; Zhang, Ying; Ma, Min

    2017-12-01

    Soluble salt in soil has a significant influence on the physical and mechanical properties of the soil. We performed desalination experiments on Lanzhou loess, a typical sulfate saline soil, to study the effects of salt on the physical and mechanical properties of the loess and compare variations in the soil properties after desalination. The Atterberg limits of the soil increased after desalination as a result of changes in the soil particle composition and grain refinement. The shear and uniaxial compressive strength of the soil increased as a result of decreased calcitic cementation and other changes to the soil structure. Scanning electron microstructure (SEM) and mercury intrusion porosimetry (MIP) procedures revealed changes to the microstructure and pore-size distribution of the Lanzhou loess after desalination.

  1. The impacts of balanced and exhaust mechanical ventilation on indoor radon

    International Nuclear Information System (INIS)

    Fisk, W.J.; Mowris, R.J.

    1987-02-01

    Models for estimating radon entry rates, indoor radon concentrations, and ventilation rates in houses with a basement or a vented crawl-space and ventilated by natural infiltration, mechanical exhaust ventilation, or balanced mechanical ventilation are described. Simulations are performed for a range of soil and housing characteristics using hourly weather data for the heating season in Spokane, WA. For a house with a basement, we show that any ventilation technique should be acceptable when the soil permeability is less than approximately 10 -12 m 2 . However, exhaust ventilation leads to substantially higher indoor radon concentrations than infiltration or balanced ventilation with the same average air exchange rate when the soil permeability is 10 -10 m 2 or greater. For houses with a crawl-space, indoor radon concentrations are lowest with balanced ventilation, intermediate with exhaust ventilation, and highest with infiltration

  2. Corrosion mechanism of a Ni-based alloy in supercritical water: Impact of surface plastic deformation

    International Nuclear Information System (INIS)

    Payet, Mickaël; Marchetti, Loïc; Tabarant, Michel; Chevalier, Jean-Pierre

    2015-01-01

    Highlights: • The dissolution of Ni and Fe cations occurs during corrosion of Ni-based alloys in SCW. • The nature of the oxide layer depends locally on the alloy microstructure. • The corrosion mechanism changes when cold-work increases leading to internal oxidation. - Abstract: Ni–Fe–Cr alloys are expected to be a candidate material for the generation IV nuclear reactors that use supercritical water at temperatures up to 600 °C and pressures of 25 MPa. The corrosion resistance of Alloy 690 in these extreme conditions was studied considering the surface finish of the alloy. The oxide scale could suffer from dissolution or from internal oxidation. The presence of a work-hardened zone reveals the competition between the selective oxidation of chromium with respect to the oxidation of nickel and iron. Finally, corrosion mechanisms for Ni based alloys are proposed considering the effects of plastically deformed surfaces and the dissolution.

  3. Dislocation density and mechanical threshold stress in OFHC copper subjected to SHPB loading and plate impact

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Qiushi [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, 621900 (China); Zhao, Feng, E-mail: ifpzfeng@163.com [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, 621900 (China); Fu, Hua; Li, Kewu [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, 621900 (China); Liu, Fusheng [Key Laboratory of Advanced Technologies of Materials, Southwest Jiaotong University, Chengdu, Sichuan, 610031 (China)

    2017-05-17

    The dislocation density and mechanical threshold stress (MTS) of oxygen-free high-thermal-conductivity (OFHC) copper loaded at strain rates in the range of 10{sup 2} to 10{sup 6} s{sup −1} were measured. Moderate-strain-rate (10{sup 2} to 10{sup 4} s{sup −1}) experiments were performed using a Split Hopkinson Pressure Bar (SHPB). A steel collar was placed around each specimen to control the maximum loading strain. High-strain-rate (10{sup 5} to 10{sup 6} s{sup −1}) experiments were carried out using a 57-mm-bore single-stage gas gun. The radial release effect was eliminated using the momentum trapping technique. The loaded samples were recovered, and the dislocation characteristics and dislocation density were determined by X-ray diffraction profile analysis. The fraction of the screw dislocation was found to decrease with increasing loading strain and strain rate. The dislocation density was found to lie between 1.8×10{sup 14} and 2.2×10{sup 15} m{sup −2}. Quasi-static reload compression tests were performed on the recovered samples at room temperature. The mechanical threshold stress (or the flow stress at 0 K) was obtained by fitting the reload stress–strain data to the MTS model. The results of analysis of the equivalent strain, mechanical threshold stress, and dislocation density measurements suggest that the relation between the mechanical threshold stress and the dislocation density can be described well by the Taylor relationship.

  4. Impact of nutrition on canine behaviour: current status and possible mechanisms

    OpenAIRE

    Bosch, G.; Beerda, B.; Hendriks, W.H.; Poel, van der, A.F.B.; Verstegen, M.W.A.

    2007-01-01

    Each year, millions of dogs worldwide are abandoned by their owners, relinquished to animal shelters, and euthanised because of behaviour problems. Nutrition is rarely considered as one of the possible contributing factors of problem behaviour. This contribution presents an overview of current knowledge on the influence of nutrition on canine behaviour and explores the underlying mechanisms by which diet may affect behaviour in animals. Behaviour is regulated by neurotransmitters and hormones...

  5. Cyanobacterial defense mechanisms against foreign DNA transfer and their impact on genetic engineering

    Directory of Open Access Journals (Sweden)

    Karina Stucken

    2013-01-01

    Full Text Available Cyanobacteria display a large diversity of cellular forms ranging from unicellular to complex multicellular filaments or aggregates. Species in the group present a wide range of metabolic characteristics including the fixation of atmospheric nitrogen, resistance to extreme environments, production of hydrogen, secondary metabolites and exopolysaccharides. These characteristics led to the growing interest in cyanobacteria across the fields of ecology, evolution, cell biology and biotechnology. The number of available cyanobacterial genome sequences has increased considerably in recent years, with more than 140 fully sequenced genomes to date. Genetic engineering of cyanobacteria is widely applied to the model unicellular strains Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942. However the establishment of transformation protocols in many other cyanobacterial strains is challenging. One obstacle to the development of these novel model organisms is that many species have doubling times of 48 h or more, much longer than the bacterial models E. coli or B. subtilis. Furthermore, cyanobacterial defense mechanisms against foreign DNA pose a physical and biochemical barrier to DNA insertion in most strains. Here we review the various barriers to DNA uptake in the context of lateral gene transfer among microbes and the various mechanisms for DNA acquisition within the prokaryotic domain. Understanding the cyanobacterial defense mechanisms is expected to assist in the development and establishment of novel transformation protocols that are specifically suitable for this group.

  6. Towards mechanism-based simulation of impact damage using exascale computing

    Science.gov (United States)

    Shterenlikht, Anton; Margetts, Lee; McDonald, Samuel; Bourne, Neil K.

    2017-01-01

    Over the past 60 years, the finite element method has been very successful in modelling deformation in engineering structures. However the method requires the definition of constitutive models that represent the response of the material to applied loads. There are two issues. Firstly, the models are often difficult to define. Secondly, there is often no physical connection between the models and the mechanisms that accommodate deformation. In this paper, we present a potentially disruptive two-level strategy which couples the finite element method at the macroscale with cellular automata at the mesoscale. The cellular automata are used to simulate mechanisms, such as crack propagation. The stress-strain relationship emerges as a continuum mechanics scale interpretation of changes at the micro- and meso-scales. Iterative two-way updating between the cellular automata and finite elements drives the simulation forward as the material undergoes progressive damage at high strain rates. The strategy is particularly attractive on large-scale computing platforms as both methods scale well on tens of thousands of CPUs.

  7. Investigation of the impact of mechanical stress on the properties of silicon strip sensors

    CERN Document Server

    Affolder, Tony; The ATLAS collaboration

    2017-01-01

    The new ATLAS tracker for phase II will be composed of silicon pixel and strip sensor modules. The strip sensor module consists of silicon sensors, boards and readout chips. Adhesives are used to connect the modular components thermally and mechanically. It was shown that the silicon sensor is exposed to mechanical stress, due to temperature difference between construction and operation. Mechanical stress can damage the sensor and can change the electrical properties. The thermal induced tensile stress near to the surface of a silicon sensor in a module was simulated and the results are compared to a cooled module. A four point bending setup was used to measure the maximum tensile stress of silicon detectors and to verify the piezoresistive effects on two recent development sensor types used in ATLAS (ATLAS07 and ATLAS12). Changes in the interstrip, bulk and bias resistance and capacitance as well as the coupling capacitance and the implant resistance were measured. The Leakage current was observed to decreas...

  8. Evaluating musical instruments

    International Nuclear Information System (INIS)

    Campbell, D. Murray

    2014-01-01

    Scientific measurements of sound generation and radiation by musical instruments are surprisingly hard to correlate with the subtle and complex judgments of instrumental quality made by expert musicians

  9. The impact of static stress change, dynamic stress change, and the background stress on aftershock focal mechanisms

    Science.gov (United States)

    Hardebeck, Jeanne L.

    2014-01-01

    The focal mechanisms of earthquakes in Southern California before and after four M ≥ 6.7 main shocks provide insight into how fault systems respond to stress and changes in stress. The main shock static stress changes have two observed impacts on the seismicity: changing the focal mechanisms in a given location to favor those aligned with the static stress change and changing the spatial distribution of seismicity to favor locations where the static stress change aligns with the background stress. The aftershock focal mechanisms are significantly aligned with the static stress changes for absolute stress changes of ≥ 0.02 MPa, for up to ~20 years following the main shock. The dynamic stress changes have similar, although smaller, effects on the local focal mechanisms and the spatial seismicity distribution. Dynamic stress effects are best observed at long periods (30–60 s) and for metrics based on repeated stress cycling in the same direction. This implies that dynamic triggering operates, at least in part, through cyclic shear stress loading in the direction of fault slip. The background stress also strongly controls both the preshock and aftershock mechanisms. While most aftershock mechanisms are well oriented in the background stress field, 10% of aftershocks are identified as poorly oriented outliers, which may indicate limited heterogeneity in the postmain shock stress field. The fault plane orientations of the outliers are well oriented in the background stress, while their slip directions are not, implying that the background stress restricts the distribution of available fault planes.

  10. The mechanically induced structural disorder in barium hexaferrite, BaFe12O19, and its impact on magnetism

    CERN Document Server

    Šepelák, V; Witte, R; Röder, J; Menzel, D; Schuster, R H; Hahn, H; Heitjans, P; Becker, K-D

    2014-01-01

    The response of the structure of the M-type barium hexaferrite (BaFe12O19) to mechanical action through high-energy milling and its impact on the magnetic behaviour of the ferrite are investigated. Due to the ability of the Fe-57 Mossbauer spectroscopic technique to probe the environment of the Fe nuclei, a valuable insight on a local atomic scale into the mechanically induced changes in the hexagonal structure of the material is obtained. It is revealed that the milling of BaFe12O19 results in the deformation of its constituent polyhedra (FeO6 octahedra, FeO4 tetrahedra and FeO5 triangular bi-pyramids) as well as in the mechanically triggered transition of the Fe3+ cations from the regular 12k octahedral sites into the interstitial positions provided by the magnetoplumbite structure. The response of the hexaferrite to the mechanical treatment is found to be accompanied by the formation of a non-uniform nanostructure consisting of an ordered crystallite surrounded/separated by a structurally disordered surfac...

  11. A Musical instrument in MEMS

    NARCIS (Netherlands)

    Engelen, Johannes Bernardus Charles; de Boer, Hans L.; de Boer, H.; Beekman, J.G.; Been, A.J.; Folkertsma, Gerrit Adriaan; Folkertsma, G.A.; Fortgens, L.; de Graaf, D.; Vocke, S.; Woldering, L.A.; Abelmann, Leon; Elwenspoek, Michael Curt

    In this work we describe a MEMS instrument that resonates at audible frequencies, and with which music can be made. The sounds are generated by mechanical resonators and capacitive displacement sensors. Damping by air scales unfavourably for generating audible frequencies with small devices.

  12. Evaluation of an Incremental Ventilation Energy Model for Estimating Impacts of Air Sealing and Mechanical Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Turner, Willliam JN [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-07-01

    Changing the rate of airflow through a home affects the annual thermal conditioning energy. Large-scale changes to airflow rates of the housing stock can significantly alter the energy consumption of the residential energy sector. However, the complexity of existing residential energy models hampers the ability to estimate the impact of policy changes on a state or nationwide level. The Incremental Ventilation Energy (IVE) model developed in this study was designed to combine the output of simple airflow models and a limited set of home characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modelers to use existing databases of home characteristics to determine the impact of policy on ventilation at a population scale. In this report, we describe the IVE model and demonstrate that its estimates of energy change are comparable to the estimates of a wellvalidated, complex residential energy model when applied to homes with limited parameterization. Homes with extensive parameterization would be more accurately characterized by complex residential energy models. The demonstration included a range of home types, climates, and ventilation systems that cover a large fraction of the residential housing sector.

  13. Building hospital capacity planning mechanisms in Poland: The impact of 2016/2017 regulatory changes.

    Science.gov (United States)

    Dubas-Jakóbczyk, Katarzyna; Sowada, Christoph; Domagała, Alicja; Więckowska, Barbara

    2018-02-07

    Capacity planning is a crucial component of modern health care governance. The aim of this paper is to analyze the requirements that need to be met to build effective hospital capacity planning mechanisms in Poland. In this context, the recent regulatory changes strongly influencing hospital sector functioning, including introduction of health care needs maps, capital investment assessment, and hospital network regulations, are analyzed. Some possible ways forward, based on review of international experiences in hospital capacity planning, are discussed. Applied methods include literature review and analysis of statistical data as well as desk analysis of key national regulations related to hospital sector. Results indicate that at the system level, the process of capacity planning involves 4 elements: capital investment in facilities, equipment, and technology; service delivery; allocation of staff; and financial resources. For hospital capacity planning to be effective, the strategic decision at the macrolevel must be complemented by appropriate management of individual hospitals. The major challenge of building hospital capacity planning mechanism in Poland is imbedding it into the overall health system strategy. Because of the lack of such a strategy, the practical implementation of the ad hoc changes, which have been introduced, shows some inconsistencies. The regulations implemented between 2016 and 2017 provided a basis for hospital capacity planning, yet still need evaluation and adjustments. Also, including a mechanism for human resources planning is of crucial importance. The regulations should provide incentives for reducing oversized hospital infrastructure with simultaneous development of the long-term and coordinated care models. Copyright © 2018 John Wiley & Sons, Ltd.

  14. Next Steps Toward Understanding Human Habitation of Space: Environmental Impacts and Mechanisms

    Science.gov (United States)

    Globus, Ruth

    2016-01-01

    Entry into low earth orbit and beyond causes profound shifts in environmental conditions that have the potential to influence human productivity, long term health, and even survival. We now have evidence that microgravity, radiation and/or confinement in space can lead to demonstrably detrimental changes in the cardiovascular (e.g. vessel function, orthostatic intolerance), musculoskeletal (muscle atrophy, bone loss) and nervous (eye, neurovestibular) systems of astronauts. Because of both the limited number of astronauts who have flown (especially females) and the high degree of individual variability in the human population, important unanswered questions about responses to the space environment remain: What are the sex differences with respect to specific physiological systems? Are the responses age-dependent and/or reversible after return to Earth? Do observed detrimental changes that resemble accelerated aging progress continuously over time or plateau? What are the mechanisms of the biological responses? Answering these important questions certainly demands a multi-pronged approach, and the study of multicellular model organisms (such as rodents and flies) already has provided opportunities for exploring those questions in some detail. Recent long duration spaceflight experiments with rodents show that mice in space provide a mammalian model that uniquely combines the influence of reduced gravitational loading with increased physical activity. In addition, multiple investigators have shown that ground-based models that simulate aspects of spaceflight (including rodent hind limb unloading to mimic weightlessness and exposure to ionizing radiation), cause various transient and persistent detrimental consequences in multiple physiological systems. In general, we have found that adverse skeletal effects of simulated weightlessness and space radiation when combined, can be quantitatively, if not qualitatively, different from the influence of each environmental

  15. A microsurgical anterior cervical approach and the immediate impact of mechanical retractors: A case control study

    Directory of Open Access Journals (Sweden)

    Rodrigo Ramos-Zúñiga

    2015-01-01

    Full Text Available Introduction: A microsurgical anterior cervical approach with discectomy and fusion (MACDF is one of the most widely used procedures for treating radicular disorders. This approach is highly successful; however, it is not free from complications. These can be associated with soft tissue injuries. Aim of the Study: The recognition of the risks for these complications should be identified for timely prevention and safe treatment. Materials and Methods: Study Design: Retrospective case control study. This study includes a retrospective case series of 37 patients, paying special attention to immediate complications related to the use of mechanical retraction of soft tissue (dysphagia, dysphonia, esophageal lesions and local hematoma; and a comparative analysis of the outcomes after changes in the retraction method. Results: All selected cases had a positive neurological symptom response in relation to neuropathic pain. Dysphagia and dysphonia were found during the first 72 h in 94.1% of the cases in which automatic mechanical retraction was used for more than one hour during the surgical procedure. A radical change was noted in the reduction of the symptoms after the use of only manual protective blades without automatic mechanical retraction: 5.1% dysphagia and 0% dysphonia in the immediate post-operative period, P = 0.001. Conclusions: Soft tissue damage due to the use of automatic retractors in MACDF is not minor and leads to general discomfort in the patient in spite of good neurological results. These problems most often occur when automatic retractors are used continuously for more than 1 hour, as well as when they are used in multiple levels. Dysphagia, dysphonia and local pain decreased with the use of transient manual blades for retraction, and with intermittent release following minimally invasive principles.

  16. Sustained Water Quality Impacts in Marine Environments Due to Mechanical Milling of Volcanic Deposits

    Science.gov (United States)

    Genareau, K. D.; Cronin, S. J.; Stewart, C.; Back, E.

    2015-12-01

    Explosive volcanic eruptions are known to be a significant geohazard, but post- or inter-eruptive processes (such as lahars, landslides, and debris avalanches) can be equally damaging to local and regional areas by remobilizing deposits. Numerous studies have found that soluble salts bound to ash grain surfaces may be quickly released into exposed waters, often lowering pH and adding trace metals with both beneficial and deleterious effects on marine flora and fauna (e.g., Fe influx initiating blooms of marine phytoplankton). Most of the cation content of pyroclastic deposits is released slowly into the environment through weathering and alteration processes. However, other pathways exist through the physical comminution of pyroclasts in fluvial and marine settings. In this case, mechanical fracturing of pyroclasts during progressive stages of disaggregation will lead to exposure of reactive particle surfaces. This study evaluates the potential, ongoing effects on water quality by experimental, mechanical milling of pyroclasts and the evaluation of released metals into exposed waters using the pyroclastic density current deposits of both the 2010 eruption of Merapi and the 2014 eruption of Kelud (Java, Indonesia), which have a bulk basaltic andesite/andesite composition (60-65 wt% SiO2). The electrical conductivity (EC) of water samples positively correlates with Ca and Sr concentrations in the case of bulk ash, whole, and crushed lapilli, but correlates with Na for the milled samples. Compared to other stages of pyroclast disaggregation, milled lapilli have the greatest effect on the concentration of alkali elements and produce a significant increase in Ca, Na, K, and Si. Mechanical milling of pyroclasts grinds down minerals and glass, resulting in an increased EC, pH, and Na concentration of exposed waters. Similar experiments are currently being conducted using basalt (50 wt% SiO2) and rhyolite (70 wt% SiO2) deposits, and these results will be presented

  17. Impact of Aggregates Size and Fibers on basic Mechanical Properties of Asphalt Emulsion—Cement Concrete

    Science.gov (United States)

    Fu, Jun; Liu, Zhihong; Liu, Jie

    2018-01-01

    Asphalt Emulsion—Cement Concrete (AECC) is currently considered as a typical semi-flexibility material. One of the disadvantages of this material is brittle fracture and lacking ductility. This study aims at accelerating the basic mechanical properties of AECC using fibers and different aggregates size. The mix of AECC was introduced and the different content of fibers and aggregates size were studied. The results showed that the smaller aggregates size could improve the young’s modulus and compressive strength as well as fiber. The modulus-compressive strength ratio of fiber reinforced AECC is always below 500.

  18. Concept of Conflict within New Economy Environment and Its Impact on the Market Mechanism

    Directory of Open Access Journals (Sweden)

    Umit Hacioglu

    2016-01-01

    Full Text Available The success of economic transition for countries mainly requires economic and politic stability. However the conflict paradigm affects the nature of economic transition. In this process, innovations have changed product technologies which have been required by economic growth. Presently, automation in standardized production industry is used as if it will take over the wage labor. Crises brought uniformities into agenda. Computer integrated manufacturing appeared in the midst of 1990s. However, production still tended to move to other countries with cheaper labor. The study focuses on interaction between the conflict and market mechanism in the light of the knowledge-based economic development.

  19. Mitigation of climate change impacts on raptors by behavioural adaptation: ecological buffering mechanisms

    Science.gov (United States)

    Wichmann, Matthias C.; Groeneveld, Jürgen; Jeltsch, Florian; Grimm, Volker

    2005-07-01

    The predicted climate change causes deep concerns on the effects of increasing temperatures and changing precipitation patterns on species viability and, in turn, on biodiversity. Models of Population Viability Analysis (PVA) provide a powerful tool to assess the risk of species extinction. However, most PVA models do not take into account the potential effects of behavioural adaptations. Organisms might adapt to new environmental situations and thereby mitigate negative effects of climate change. To demonstrate such mitigation effects, we use an existing PVA model describing a population of the tawny eagle ( Aquila rapax) in the southern Kalahari. This model does not include behavioural adaptations. We develop a new model by assuming that the birds enlarge their average territory size to compensate for lower amounts of precipitation. Here, we found the predicted increase in risk of extinction due to climate change to be much lower than in the original model. However, this "buffering" of climate change by behavioural adaptation is not very effective in coping with increasing interannual variances. We refer to further examples of ecological "buffering mechanisms" from the literature and argue that possible buffering mechanisms should be given due consideration when the effects of climate change on biodiversity are to be predicted.

  20. The impact of electricity market design upon investment under uncertainty: The effectiveness of capacity mechanisms

    International Nuclear Information System (INIS)

    Vries, Laurens de; Heijnen, Petra

    2008-01-01

    This paper presents an analysis of different market designs under uncertainty about the future growth rate of demand. Markets for electricity generation appear to be prone to an investment cycle due to their capital-intensiveness and the long lead time of new generation facilities. We tested the stability of different capacity mechanisms in the presence of uncertainty regarding the demand growth rate with a stochastic dynamic model. Investment decisions were assumed to maximize profit, based on an assumed growth rate of demand that was equal to the rolling average of the previous five years. All capacity mechanisms proved effective in reducing the tendency towards an investment cycle, but to different degrees. Interestingly, an oligopoly that is able to raise average prices by 10% would also be able to substantially reduce price volatility and decrease the risk of shortages by increasing the reserve margin. Benefits of such a strategy for the generating companies could be that it would deter new market entrants and stave off the political attention that shortages and price spikes would bring about. However, the benefits to consumers are compromised by the lack of economic efficiency and distributional effects of an oligopoly, while the stability of such an oligopolistic strategy can be questioned. The most attractive solution is a system of reliability contracts, which can be used to stabilize both investment and prices, while reducing market power and providing more efficient operational incentives to generating companies. (author)

  1. Impacts of Hydrate Distribution on the Hydro-Thermo-Mechanical Properties of Hydrate-Bearing Sediments

    Science.gov (United States)

    Dai, S.; Seol, Y.

    2015-12-01

    In general, hydrate makes the sediments hydraulically less conductive, thermally more conductive, and mechanically stronger; yet the dependency of these physical properties on hydrate saturation varies with hydrate distribution and morphology. Hydrate distribution in sediments may cause the bulk physical properties of their host sediments varying several orders of magnitude even with the same amount of hydrate. In natural sediments, hydrate morphology is inherently governed by the burial depth and the grain size of the host sediments. Compare with patchy hydrate, uniformly distributed hydrate is more destructive to fluid flow, yet leads to higher gas and water permeability during hydrate dissociation due to the easiness of forming percolation paths. Water and hydrate have similar thermal conductivity values; the bulk thermal conductivity of hydrate-bearing sediments depends critically on gas-phase saturation. 60% of gas saturation may result in evident thermal conductivity drop and hinder further gas production. Sediments with patchy hydrate yield lower stiffness than that with cementing hydrate but higher stiffness than that with pore filling and loading bearing hydrate. Besides hydrate distribution, the stress state and loading history also play an important role in the mechanical behavior of hydrate-bearing sediments.

  2. Mechanical and chemical responses of low-velocity impacted RDX and HMX explosive powders

    Science.gov (United States)

    Wu, Yanqing; Guo, Hongfu; Huang, Fenglei; Bao, Xiaowei; Explosion; damage Team

    2017-06-01

    The experimental analyses of mechanical and chemical responses of RDX and HMX particles were performed based on the optimized drop-weight experimental system equipped with the High-Speed Camera (HSC). It has been found that Jetting phenomenon observed by HSC is the result of the energy released by gaseous products, which push the pulverized or melted explosives to splash radially. Jetting is the only and the most obvious difference between reactive and inert particles prior to combustion so that jetting can be regarded as the sign of ignition. Area expansion velocity, jetting velocity, and flame propagation velocity have been estimated via image processing, making it possible to characterize mechanical deformation and violence of reaction of each stage. Hot-spots coalescence promotes flame propagation whose velocity reflects the violence of deflagration reaction. Jetting appearance time can be used to determine time-to-ignition more accurately than other ways. For RDX, molten phase plays an important role to the formation of the hot-spots. Multiple particles experienced more severe burning reactions than an individual particle. China National Nature Science Foundation (11572045), ``Science Challenging Program'' (JCKY2016212A501),opening fund from Safety ammunition research and Development Center (RMC2015B03).

  3. The impact of climate and composition on playa surface roughness: Investigation of atmospheric mineral dust emission mechanisms

    Science.gov (United States)

    Tollerud, H. J.; Fantle, M. S.

    2011-12-01

    Atmospheric mineral dust has a wide range of impacts, including the transport of elements in geochemical cycles, health hazards from small particles, and climate forcing via the reflection of sunlight from dust particles. In particular, the mineral dust component of climate forcing is one of the most uncertain elements in the IPCC climate forcing summary. Mineral dust is also an important component of geochemical cycles. For instance, dust inputs to the ocean potentially affect the iron cycle by stimulating natural iron fertilization, which could then modify climate via the biological pump. Also dust can transport nutrients over long distances and fertilize nutrient-poor regions, such as island ecosystems or the Amazon rain forest. However, there are still many uncertainties in quantifying dust emissions from source regions. One factor that influences dust emission is surface roughness and texture, since a weak, unconsolidated surface texture is more easily ablated by wind than a strong, hard crust. We are investigating the impact of processes such as precipitation, groundwater evaporation, and wind on surface roughness in a playa dust source region. We find that water has a significant influence on surface roughness. We utilize ESA's Advanced Synthetic Aperture Radar (ASAR) instrument to measure roughness in the playa. A map of roughness indicates where the playa surface is smooth (on the scale of centimeters) and potentially very strong, and where it is rough and might be more sensitive to disturbance. We have analyzed approximately 40 ASAR observations of the Black Rock Desert from 2007-2011. In general, the playa is smoother and more variable over time relative to nearby areas. There is also considerable variation within the playa. While the playa roughness maps changed significantly between summers and between observations during the winters, over the course of each summer, the playa surface maintained essentially the same roughness pattern. This suggests that

  4. The Impact of Parbaking on the Crumb Firming Mechanism of Fully Baked Tin Wheat Bread.

    Science.gov (United States)

    Nivelle, Mieke A; Bosmans, Geertrui M; Delcour, Jan A

    2017-11-22

    The impact of parbaking on the quality and shelf life of large tin bread baked from 270 g of wheat flour was investigated using a proton nuclear magnetic resonance method combined with techniques that measure at different length scales. With increasing partial baking time, the resilience of fresh partially baked crumb increased because of its more extended amylose and gluten networks. During subsequent storage, the crumb became more firm due to an increased extent of amylopectin retrogradation and moisture redistribution. Although only amylopectin retrogradation was reversed during final baking, a fresh fully baked (FB) bread with reversed crumb softness was obtained. Furthermore, the rate of crumb firming during final storage of FB bread was not higher than that of conventionally baked bread. This was attributed to the high crumb to crust ratio of large tin bread which caused the crumb moisture content to remain sufficiently high despite nonreversible moisture redistribution during intermediate storage.

  5. Changes in parents' spanking and reading as mechanisms for Head Start impacts on children.

    Science.gov (United States)

    Gershoff, Elizabeth T; Ansari, Arya; Purtell, Kelly M; Sexton, Holly R

    2016-06-01

    This study examined whether Head Start, the nation's main two-generation program for low-income families, benefits children in part through positive changes in parents' use of spanking and reading to children. Data were drawn from the 3-year-old cohort of the national evaluation of the Head Start program known as the Head Start Impact Study (N = 2,063). Results indicated that Head Start had small, indirect effects on children's spelling ability at Age 4 and their aggression at Age 4 through an increase in parents' reading to their children. Taken together, the results suggest that parents play a role in sustaining positive benefits of the Head Start program for children's behavior and literacy skills, one that could be enhanced with a greater emphasis on parent involvement and education. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  6. How mechanics shaped the modern world

    CERN Document Server

    Allen, David H

    2013-01-01

    Presents an offbeat, nontechnical chronology of the history of mechanics, from the Big Bang to present day Lays out a complicated scientific subject in a rapid-fire narrative that is both interesting and informative for the non-specialist reader Covers subjects ranging from Egyptian civilization, music and musical instruments, art, and climate dynamics and demonstrates how their evolution both impacted and was impacted by humankind's understanding of mechanicsThoughtfully examines the current state of mechanics and possibilities for future research and innovation

  7. Determining the climate impact of the German government's Integrated Energy and Climate Programme (IEKP) and proposing a plan to continuously monitor its climate impact. Work package 1. Qualitative assessment of the instruments in an Integrated Energy and Climate Programme (IEKP); Ermittlung der Klimaschutzwirkung des Integrierten Energie- und Klimaschutzprogramms der Bundesregierung IEKP und Vorschlag fuer ein Konzept zur kontinuierlichen Ueberpruefung der Klimaschutzwirkung des IEKP. Arbeitspaket 1. Qualitative Einschaetzung der Instrumente im Integrierten Energie- und Klimaschutzprogramm (IEKP)

    Energy Technology Data Exchange (ETDEWEB)

    Doll, Claus; Eichhammer, Wolfgang; Fleiter, Tobias [Fraunhofer-Institut fuer System- und Innovationsforschung, Karlsruhe (DE)] (and others)

    2012-02-15

    In August 2007, the key elements for an integrated energy and climate program (IECP) were adopted within the Meseberg resolutions. The implementation of the Meseberg resolutions were performed in three packages primarily including amending laws as well as support measures. The authors of the contribution under consideration compare the climate protection instruments realized by IECP with the presentations in the IECP. This comparison is based on an analysis of documents and research projects in the periphery of the IECP and on a survey of target groups and other relevant actors on the effectiveness of the IECP mechanisms. The result of this comparison is summarized in form of 27 measures.

  8. Instrument to collect fogwater for chemical analysis

    OpenAIRE

    Jacob, Daniel J.; Waldman, Jed M.; Haghi, Mehrdad; Hoffmann, Michael R.; Flagan, Richard C.

    1985-01-01

    An instrument is presented which collects large samples of ambient fogwater by impaction of droplets on a screen. The collection efficiency of the instrument is determined as a function of droplet size, and it is shown that fog droplets in the range 3–100-µm diameter are efficiently collected. No significant evaporation or condensation occurs at any stage of the collection process. Field testing indicates that samples collected are representative of the ambient fogwater. The instrument may ea...

  9. Mechanisms of ilmenite reduction and their impact on the design of effective reactor systems

    Science.gov (United States)

    Briggs, R. A.; Sacco, A.

    1991-01-01

    One of the first activities at a lunar base could be oxygen recovery from ilmenite (FeTiO3). Oxygen produced from lunar soils could be used to fuel transportation vehicles operating in near-earth space. The first step in developing a suitable reactor system for lunar operation is to determine the mechanisms and rates of oxygen removal from ilmenite. In-situ gravimetric measurements and microscopic examinations were used to determine the hydrogen reduction mechanisms of synthetic ilmenite discs between 823 to 1353 K. A shrinking core reaction model, modified to account for the growth of an iron film on the surface of discs, was capable of predicting experimentally observed conversion-time relationships. The observed reduction mechanism, kinetic rates, and associated activation energy established a base line from which comparisons could be made to improve oxygen yield and removal rates. One proposed technique to improve the rate and extent of oxygen removal was to preoxidize ilmenite. Preoxidation is commonly used during the reduction of ilmenite ores in the iron industry and has been employed for many years to lower operating temperatures and increase reduction rates. This technology could prove beneficial for oxygen production facilities on the Moon as less massive reactor vessels and/or less energy could be associated with a process including preoxidation. X ray diffraction and energy dispersive spectroscopy were utilized to follow the progression of ilmenite oxidation at 1123 and 1140 K and the reduction of pseudobrookite (Fe2TiO5) at 873 and 973 K. Structures formed during the progress of oxidation were related to the system's phase diagrams. Results indicated that after initially producing ilmenite-hematite solutions and rutile (TiO2), pseudobrookite was the end product of oxidation at all temperatures examined (1049 to 1273 K). Initial results from the reduction of pseudobrookite indicate a series of phases are produced including ferropseudobrookite (FeTi2O5

  10. IOT Overview: IR Instruments

    Science.gov (United States)

    Mason, E.

    In this instrument review chapter the calibration plans of ESO IR instruments are presented and briefly reviewed focusing, in particular, on the case of ISAAC, which has been the first IR instrument at VLT and whose calibration plan served as prototype for the coming instruments.

  11. Structural and mechanical study of concrete made from cementitious materials of low environmental impact

    Science.gov (United States)

    González, A. K.; Montaño, A. M.; González, C. P.; Santos, A.

    2017-12-01

    This work shows the results obtained by replacing Type I Portland®, by cementitious geopolymers materials, derived from minerals, in concrete mixtures. Synthesis of both geopolymers through alkaline activation of two alluminosilicates: Bentonite and Pumice with sodium silicate (Na2SiO3). XRD, SEM and XRDE are used to structural study of new geopolymers. Concrete mixtures with replacement of Portland have 10% and 30% of geopolymer. Finally, concrete mortars formed were mechanically analysed according to ICONTEC 220 at 7, 14, 28, 41, 90 and 120 days of cure. Results shows that compressive strength of concrete from Bentonite and Pumice are almost the same for the standard concrete at 28 days of cure. At 90 days of cure, compression resistance of concrete from Pumice at 10% is even higher than those that standard concrete shows.

  12. Tensile Deformation Temperature Impact on Microstructure and Mechanical Properties of AISI 316LN Austenitic Stainless Steel

    Science.gov (United States)

    Xiong, Yi; He, Tiantian; Lu, Yan; Ren, Fengzhang; Volinsky, Alex A.; Cao, Wei

    2018-03-01

    Uniaxial tensile tests were conducted on AISI 316LN austenitic stainless steel from - 40 to 300 °C at a rate of 0.5 mm/min. Microstructure and mechanical properties of the deformed steel were investigated by optical, scanning and transmission electron microscopies, x-ray diffraction, and microhardness testing. The yield strength, ultimate tensile strength, elongation, and microhardness increase with the decrease in the test temperature. The tensile fracture morphology has the dimple rupture feature after low-temperature deformations and turns to a mixture of transgranular fracture and dimple fracture after high-temperature ones. The dominating deformation microstructure evolves from dislocation tangle/slip bands to large deformation twins/slip bands with temperature decrease. The deformation-induced martensite transformation can only be realized at low temperature, and its quantity increases with the decrease in the temperature.

  13. Elevated venous thromboembolism risk in preeclampsia: molecular mechanisms and clinical impact.

    Science.gov (United States)

    Egan, Karl; Kevane, Barry; Ní Áinle, Fionnuala

    2015-08-01

    Venous thromboembolism (VTE) remains a leading cause of maternal death and morbidity in the developed world. Strategies for prevention of VTE in pregnancy have been the subject of recent guidelines and consensus statements. These guidelines recommend thrombosis prevention in women who have risk factors associated with an elevated VTE risk. Preeclampsia is characterized by maternal hypertension and proteinuria developing after 20 weeks gestation, complicating up to 7% of pregnancies and is associated with a massive annual morbidity and mortality burden. Women with preeclampsia have been shown to be at increased risk of VTE with studies to date suggesting that this risk may be up to 5-fold greater than the risk of pregnancy-associated VTE in the general population. Despite the fact that preeclampsia is so common and potentially devastating, our understanding of its pathogenesis and potential therapeutic strategies remain poor. In addition, the mechanisms underlying the prothrombotic phenotype in preeclampsia are also poorly characterized although a number of potential mechanisms have been postulated. Derangements of platelet and endothelial activation and impairment of endogenous anti-coagulant pathways have been reported and may contribute to the observed VTE risk. Recently, evidence for the role of neutrophil extracellular traps (NETs) and cell-free DNA in the pathogenesis of VTE has emerged and some evidence exists to suggest that this may be of relevance in preeclampsia. Future studies aimed at understanding the diagnostic and potential therapeutic relevance of this procoagulant state are likely to be of enormous clinical benefit for pregnant women affected with this potentially devastating condition. © 2015 Authors; published by Portland Press Limited.

  14. Health physics instrument manual

    International Nuclear Information System (INIS)

    Gupton, E.D.

    1978-08-01

    The purpose of this manual is to provide apprentice health physics surveyors and other operating groups not directly concerned with radiation detection instruments a working knowledge of the radiation detection and measuring instruments in use at the Laboratory. The characteristics and applications of the instruments are given. Portable instruments, stationary instruments, personnel monitoring instruments, sample counters, and miscellaneous instruments are described. Also, information sheets on calibration sources, procedures, and devices are included. Gamma sources, beta sources, alpha sources, neutron sources, special sources, a gamma calibration device for badge dosimeters, and a calibration device for ionization chambers are described

  15. Astronomical Instruments in India

    Science.gov (United States)

    Sarma, Sreeramula Rajeswara

    The earliest astronomical instruments used in India were the gnomon and the water clock. In the early seventh century, Brahmagupta described ten types of instruments, which were adopted by all subsequent writers with minor modifications. Contact with Islamic astronomy in the second millennium AD led to a radical change. Sanskrit texts began to lay emphasis on the importance of observational instruments. Exclusive texts on instruments were composed. Islamic instruments like the astrolabe were adopted and some new types of instruments were developed. Production and use of these traditional instruments continued, along with the cultivation of traditional astronomy, up to the end of the nineteenth century.

  16. Thermal-mechanical-chemical responses of polymer-bonded explosives using a mesoscopic reactive model under impact loading.

    Science.gov (United States)

    Wang, XinJie; Wu, YanQing; Huang, FengLei

    2017-01-05

    A mesoscopic framework is developed to quantify the thermal-mechanical-chemical responses of polymer-bonded explosive (PBX) samples under impact loading. A mesoscopic reactive model is developed for the cyclotetramethylenetetranitramine (HMX) crystal, which incorporates nonlinear elasticity, crystal plasticity, and temperature-dependent chemical reaction. The proposed model was implemented in the finite element code ABAQUS by the user subroutine VUMAT. A series of three-dimensional mesoscale models were constructed and calculated under low-strength impact loading scenarios from 100m/s to 600m/s where only the first wave transit is studied. Crystal anisotropy and microstructural heterogeneity are responsible for the nonuniform stress field and fluctuations of the stress wave front. At a critical impact velocity (≥300m/s), a chemical reaction is triggered because the temperature contributed by the volumetric and plastic works is sufficiently high. Physical quantities, including stress, temperature, and extent of reaction, are homogenized from those across the microstructure at the mesoscale to compare with macroscale measurements, which will advance the continuum-level models. The framework presented in this study has important implications in understanding hot spot ignition processes and improving predictive capabilities in energetic materials. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Quantifying potential health impacts of cadmium in cigarettes on smoker risk of lung cancer: a portfolio-of-mechanisms approach.

    Science.gov (United States)

    Cox, Louis Anthony Tony

    2006-12-01

    This article introduces an approach to estimating the uncertain potential effects on lung cancer risk of removing a particular constituent, cadmium (Cd), from cigarette smoke, given the useful but incomplete scientific information available about its modes of action. The approach considers normal cell proliferation; DNA repair inhibition in normal cells affected by initiating events; proliferation, promotion, and progression of initiated cells; and death or sparing of initiated and malignant cells as they are further transformed to become fully tumorigenic. Rather than estimating unmeasured model parameters by curve fitting to epidemiological or animal experimental tumor data, we attempt rough estimates of parameters based on their biological interpretations and comparison to corresponding genetic polymorphism data. The resulting parameter estimates are admittedly uncertain and approximate, but they suggest a portfolio approach to estimating impacts of removing Cd that gives usefully robust conclusions. This approach views Cd as creating a portfolio of uncertain health impacts that can be expressed as biologically independent relative risk factors having clear mechanistic interpretations. Because Cd can act through many distinct biological mechanisms, it appears likely (subjective probability greater than 40%) that removing Cd from cigarette smoke would reduce smoker risks of lung cancer by at least 10%, although it is possible (consistent with what is known) that the true effect could be much larger or smaller. Conservative