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Sample records for creep-fatigue interaction testing

  1. Creep, fatigue and creep-fatigue interactions in modified 9% Chromium - 1% Molybdenum (P91) steels

    Science.gov (United States)

    Kalyanasundaram, Valliappa

    Grade P91 steel, from the class of advanced high-chrome ferritic steels, is one of the preferred materials for many elevated temperature structural components. Creep-fatigue (C-F) interactions, along with oxidation, can accelerate the kinetics of damage accumulation and consequently reduce such components' life. Hence, reliable C-F test data is required for meticulous consideration of C-F interactions and oxidation, which in turn is vital for sound design practices. It is also imperative to develop analytical constitutive models that can simulate and predict material response under various long-term in-service conditions using experimental data from short-term laboratory experiments. Consequently, the major objectives of the proposed research are to characterize the creep, fatigue and C-F behavior of grade P91 steels at 625 C and develop robust constitutive models for simulating/predicting their microstructural response under different loading conditions. This work will utilize experimental data from 16 laboratories worldwide that conducted tests (creep, fatigue and C-F) on grade P91 steel at 625°C in a round-robin (RR) program. Along with 7 creep deformation and rupture tests, 32 pure fatigue and 46 C-F tests from the RR are considered in this work. A phenomenological constitutive model formulated in this work needs just five fitting parameters to simulate/predict the monotonic, pure fatigue and C-F behavior of grade P91 at 625 C. A modified version of an existing constitutive model is also presented for particularly simulating its isothermal creep deformation and rupture behavior. Experimental results indicate that specimen C-F lives, as measured by the 2% load drop criterion, seem to decrease with increasing strain ranges and increasing hold times at 625°C. Metallographic assessment of the tested specimens shows that the damage mode in both pure fatigue and 600 seconds hold time cyclic tests is predominantly transgranular fatigue with some presence of

  2. A life evaluation under creep-fatigue-environment interaction of Ni-base wrought alloys

    International Nuclear Information System (INIS)

    Hattori, Hiroshi; Kitagawa, Masaki; Ohtomo, Akira; Itoh, Mitsuyoshi

    1986-01-01

    In order to determine a failure criteria under cyclic loading and affective environment for HTGR systems, a series of strain controlled low-cycle fatigue tests were carried out at HTGR maximum gas temperatures in air, in vacuum and in HTGR helium environments on two nickel-base wrought alloys, namely Inconel 617 and Hastelloy XR. This paper first describes the creep-fatigue-environment properties of these alloys followed by a proposal of an evaluation method of creep-fatigue-environment interaction based on the experimental data to define the more reasonable design criteria, which is a modification of the linear damage summation rule. Second, the creep-fatigue properties of Hastelloy XR at 900 deg C and the result evaluated by this proposed method are shown. This criterion is successfully applied to the life prediction at 900 deg C. In addition, the creep-fatigue properties of Hastelloy XR-II are discussed. (author)

  3. Standard test method for creep-fatigue testing

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers the determination of mechanical properties pertaining to creep-fatigue deformation or crack formation in nominally homogeneous materials, or both by the use of test specimens subjected to uniaxial forces under isothermal conditions. It concerns fatigue testing at strain rates or with cycles involving sufficiently long hold times to be responsible for the cyclic deformation response and cycles to crack formation to be affected by creep (and oxidation). It is intended as a test method for fatigue testing performed in support of such activities as materials research and development, mechanical design, process and quality control, product performance, and failure analysis. The cyclic conditions responsible for creep-fatigue deformation and cracking vary with material and with temperature for a given material. 1.2 The use of this test method is limited to specimens and does not cover testing of full-scale components, structures, or consumer products. 1.3 This test method is primarily ...

  4. Standard test method for creep-fatigue crack growth testing

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers the determination of creep-fatigue crack growth properties of nominally homogeneous materials by use of pre-cracked compact type, C(T), test specimens subjected to uniaxial cyclic forces. It concerns fatigue cycling with sufficiently long loading/unloading rates or hold-times, or both, to cause creep deformation at the crack tip and the creep deformation be responsible for enhanced crack growth per loading cycle. It is intended as a guide for creep-fatigue testing performed in support of such activities as materials research and development, mechanical design, process and quality control, product performance, and failure analysis. Therefore, this method requires testing of at least two specimens that yield overlapping crack growth rate data. The cyclic conditions responsible for creep-fatigue deformation and enhanced crack growth vary with material and with temperature for a given material. The effects of environment such as time-dependent oxidation in enhancing the crack growth ra...

  5. IFMIF - Design Study for in Situ Creep Fatigue Tests

    International Nuclear Information System (INIS)

    Gordeev, S.; Heinzel, V.; Simakov, St.; Stratmanns, E.; Vladimirov, P.; Moeslang, A.

    2006-01-01

    While the high flux volume (20-50 dpa/fpy) of the International Fusion Materials Irradiation Facility (IFMIF) is dedicated to the irradiation of ∼ 1100 qualified specimens that will be post irradiation examined after disassembling in dedicated Hot Cells, various in situ experiments are foreseen in the medium flux volume (1-20 dpa/fpy). Of specific importance for structural lifetime assessments of fusion power reactors are instrumented in situ creep-fatigue experiments, as they can simulate realistically a superposition of thermal fatigue or creep fatigue and irradiation with fusion relevant neutrons. Based on former experience with in situ fatigue tests under high energy light ion irradiation, a design study has been performed to evaluate the feasibility of in situ creep fatigue tests in the IFMIF medium flux position. The vertically arranged test module for such experiments consists basically of a frame similar to a universal testing machine, but equipped with three pulling rods, driven by independent step motors, instrumentation systems and specimen cooling systems. Therefore, three creep fatigue specimens may be tested at one time in this apparatus. Each specimen is a hollow tube with coolant flow in the specimen interior to maintain individual specimen temperatures. The recently established IFMIF global 3D geometry model was used together the latest McDeLicious code for the neutral and charged particle transport calculations. These comprehensive neutronics calculations have been performed with a fine special resolution of 0.25 cm 3 , showing among others that the specimens will be irradiated with a homogeneous damage rate of up to 13(∼ 9%) dpa/fpy and a fusion relevant damage to helium ratio of 10-12 appm He/dpa. In addition, damage and gas production rates as well as the heat deposition in structural parts of the test module have been calculated. Despite of the vertical gradients in the nuclear heating, CFD code calculations with STAR-CD revealed very

  6. Crack Growth Behaviour of P92 Steel Under Creep-fatigue Interaction Conditions

    Directory of Open Access Journals (Sweden)

    JING Hong-yang

    2017-05-01

    Full Text Available Creep-fatigue interaction tests of P92 steel at 630℃ under stress-controlled were carried out, and the crack propagation behaviour of P92 steel was studied. The fracture mechanism of crack growth under creep-fatigue interaction and the transition points in a-N curves were analyzed based on the fracture morphology. The results show that the fracture of P92 steel under creep-fatigue interaction is creep ductile fracture and the (Ctavg parameter is employed to demonstrate the crack growth behaviour; in addition, the fracture morphology shows that the crack growth for P92 steel under creep-fatigue interaction is mainly caused by the nucleation and growth of the creep voids and micro-cracks. Furthermore, the transition point of a-lg(Ni/Nf curve corresponds to the turning point of initial crack growth changed into steady crack growth while the transition point of (da/dN-N curve exhibits the turning point of steady creep crack growth changed into the accelerated crack growth.

  7. Experimental investigation on low cycle fatigue and creep-fatigue interaction of DZ125 in different dwell time at elevated temperatures

    International Nuclear Information System (INIS)

    Shi Duoqi; Liu Jinlong; Yang Xiaoguang; Qi Hongyu; Wang Jingke

    2010-01-01

    Research highlights: → This paper has researched creep-fatigue interaction of directionally solidified superalloy DZ125 with different dwell time at high temperature combined with micro-mechanism by experiment. → The results indicated that the life of creep-fatigue decreases as dwell time increases, but the life of this alloy was almost unchanged when dwell time exceeds a critical value at 850 deg. C. - Abstract: The low cycle fatigue (LCF) and creep-fatigue tests have been conducted with directionally solidified nickel-based superalloy DZ125 at 850 and 980 deg. C to study the creep-fatigue interaction behavior of alloy with different dwell time. On the average, the life of creep-fatigue tests are about 70% less than the life of LCF tests under the same strain range at 850 deg. C. The life of creep-fatigue decreases as dwell time increases, but the life of this alloy was almost unchanged when dwell time exceeds a critical value at 850 deg. C. Scanning electron microscope (SEM) analyses of the fracture revealed that the fracture modes were influenced by different way of loading. In case of LCF, the primary fracture mode was transgranular, while in case of creep-fatigue, the primary fracture mode was mixed with transgranular and intergranular. There were also obvious different morphologies of surface crack between LCF and creep-fatigue.

  8. Creep-fatigue defect assessment test and analysis of high temperature structure

    International Nuclear Information System (INIS)

    Kim, Jong-Bum; Lee, H. Y.; Park, C. K.; Joo, Y. S.; Lee, J. H.

    2005-03-01

    The creep-fatigue damage evaluation and the defect assessment are the one of key parameters to ascertain the structural integrity of high temperature structures. In this study, the creep-fatigue test with geometrically nonlinear structure including through wall defects was performed to examine the structural integrity of the defect structure and to validate the inelastic analysis code NONSTA. The creep-fatigue damage was examined by a portable zoom microscope and the replication technics allowed to observe the structure surface. After 400 cycles of testing, no apparent creep-fatigue was observed except the defect front. At the defect front, creep-fatigue crack initiation was observed. The commercial finite element analysis softwares ANSYS and ABAQUS were used for the corresponding structural analysis. Both elastic analysis and inelastic analysis using NONSTA code were performed with collected temperature profile from the test and the strain results of analyses agree well with those from the test. The creep-fatigue damage was assessed per ASME-NH utilizing analysis results and the creep-fatigue crack initiation was assessed per RCC-MR A16. The results show good agreement between analysis and test

  9. Modeling Creep-Fatigue-Environment Interactions in Steam Turbine Rotor Materials for Advanced Ultra-supercritical Coal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Chen [General Electric Global Research, Niskayuna, NY (United States)

    2014-04-01

    The goal of this project is to model creep-fatigue-environment interactions in steam turbine rotor materials for advanced ultra-supercritical (A-USC) coal power Alloy 282 plants, to develop and demonstrate computational algorithms for alloy property predictions, and to determine and model key mechanisms that contribute to the damages caused by creep-fatigue-environment interactions.

  10. LCF life prediction for waspaloy in the creep-fatigue interaction regime

    International Nuclear Information System (INIS)

    Yeom, Jong Taek; Park, Nho Kwang

    2001-01-01

    This paper describes the empirical rule of strain rate modified linear accumulation of creep damage(SRM rule) for Low-Cycle Fatigue(LCF) life prediction of Waspaloy in the creep-fatigue interaction regime and Chaboche type unified viscoplastic model predicting the stress-strain response in various cyclic loading conditions. The comparison of the experimental data and the predictions for strain controlled LCF tests carried out for various strain ranges at 600 .deg. C and 650 .deg. C was made. Chaboche type unified viscoplastic model described efficiently the inelastic deformation behavior during LCF tests. Crack-initiation lifting method to predict the material life was investigated with Strain Rate Modification(SRM) rule. The application of SRM rule to LCF tests on Waspaloy indicated a good agreement between measured and predicted cycles to failure

  11. Microstructure evolution in a 2618 aluminium alloy during creep-fatigue tests

    Energy Technology Data Exchange (ETDEWEB)

    Novy, Frantisek; Hadzima, Branislav [Zilina Univ. (Slovakia). Dept. of Materials Engineering; Janecek, Milos; Kral, Robert [Charles Univ., Prague (Czech Republic). Dept. of Physics of Materials

    2012-06-15

    Microstructure changes in the 2 618 aluminium alloy during creep-fatigue tests were studied. These tests simulate the conditions of the application of this alloy in devices for the exhaustion of hot gasses generated during fire in closed or difficultly accessible areas. Creep-fatigue tests result in high dislocation density in subgrains and narrow subgrain boundaries, in contrast to creep tests reported in our previous work where large subgrains were observed with relatively wide subgrain boundaries and relatively low dislocation density in grains. Extensive precipitation occurred with denuded (precipitate-free) zones along grain boundaries. The coherent S-phase (Al{sub 2}CuMg) transformed into partially coherent needle-shaped S' precipitates. Superior stress amplitude caused reduced lifetime and wider denuded zones. A model of the formation of denuded zones along (sub)-grain boundaries was proposed. (orig.)

  12. Evaluation of Creep-Fatigue Integrity for High Temperature Pressure Vessel in a Sodium Test Loop

    International Nuclear Information System (INIS)

    Lee, Hyeong-Yeon; Lee, Dong-Won

    2014-01-01

    In this study, high temperature integrity evaluation on a pressure vessel of the expansion tank operating at elevated temperature of 510°C in the sodium test facility of the SEFLA(Sodium Thermal-hydraulic Experiment Loop for Finned-tube Sodium-to-Air heat exchanger) to be constructed at KAERI has been performed. Evaluations of creep fatigue damage based on a full 3D finite element analyses were conducted for the expansion tank according to the recent elevated temperature design codes of ASME Section III Subsection NH and French RCC-MRx. It was shown that the expansion tank maintains its integrity under the intended creep-fatigue loads. Quantitative code comparisons were conducted for the pressure vessel of austenitic stainless steel 316L

  13. Report on FY15 Alloy 617 SMT Creep-Fatigue Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanli [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jetter, Robert I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Baird, Seth T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pu, Chao [Univ. of Tennessee, Knoxville, TN (United States); Sham, Sam [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-06-22

    For the temperature range of 990-950C, Alloy 617 is a candidate IHX structural material for high temperature gas reactors (HTGRs) because of its high temperature creep properties. Also, its superior strength over a broad temperature range also offers advantages for certain component applications. In order for the designers to be able to use Alloy 617 for these high temperature components, Alloy 617 has to be approved for use in Section III (the nuclear section) of the ASME (American Society of Mechanical Engineers) Boiler and Pressure Vessel Code. A plan has been developed to propose a Code Case for use of Alloy 617 at elevated temperature in Section III of the ASME Code by September 2015. There has not been a new high temperature material approved for use in Section III for almost 20 years. The Alloy 617 Code Case effort would lead the way to establish a path for Code qualification of new high temperature materials of interest to other advanced SMRs. Creep-fatigue at elevated temperatures is the most damaging structural failure mode. In the past 40 years significant efforts have been devoted to the elevated temperature Code rule development in Section III, Subsection NH* of the ASME Boiler and Pressure Vessel Code, to ascertain conservative structural designs to prevent creep-fatigue failure. The current Subsection NH creep-fatigue procedure was established by the steps of (1) analytically obtaining a detailed stress-strain history, (2) comparing the stress and strain components to cyclic test results deconstructed into stress and strain quantities, and (3) recombining the results to obtain a damage function in the form of the so-called creep-fatigue damage-diagram. The deconstruction and recombination present difficulties in evaluation of test data and determination of cyclic damage in design. The uncertainties in these steps lead to the use of overly conservative design factors in the current creep-fatigue procedure. In addition, and of major significance to the

  14. Multi Resolution In-Situ Testing and Multiscale Simulation for Creep Fatigue Damage Analysis of Alloy 617

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yongming [Arizona State Univ., Tempe, AZ (United States). School for Engineering of Matter, Transport and Energy; Oskay, Caglar [Vanderbilt Univ., Nashville, TN (United States). Dept. of Civil and Environmental Engineering

    2017-04-30

    This report outlines the research activities that were carried out for the integrated experimental and simulation investigation of creep-fatigue damage mechanism and life prediction of Nickel-based alloy, Inconel 617 at high temperatures (950° and 850°). First, a novel experimental design using a hybrid control technique is proposed. The newly developed experimental technique can generate different combinations of creep and fatigue damage by changing the experimental design parameters. Next, detailed imaging analysis and statistical data analysis are performed to quantify the failure mechanisms of the creep fatigue of alloy 617 at high temperatures. It is observed that the creep damage is directly associated with the internal voids at the grain boundaries and the fatigue damage is directly related to the surface cracking. It is also observed that the classical time fraction approach does not has a good correlation with the experimental observed damage features. An effective time fraction parameter is seen to have an excellent correlation with the material microstructural damage. Thus, a new empirical damage interaction diagram is proposed based on the experimental observations. Following this, a macro level viscoplastic model coupled with damage is developed to simulate the stress/strain response under creep fatigue loadings. A damage rate function based on the hysteresis energy and creep energy is proposed to capture the softening behavior of the material and a good correlation with life prediction and material hysteresis behavior is observed. The simulation work is extended to include the microstructural heterogeneity. A crystal plasticity finite element model considering isothermal and large deformation conditions at the microstructural scale has been developed for fatigue, creep-fatigue as well as creep deformation and rupture at high temperature. The model considers collective dislocation glide and climb of the grains and progressive damage accumulation of

  15. Sequential creep-fatigue interaction in austenitic stainless steel type 316L-SPH

    International Nuclear Information System (INIS)

    Tavassoli, A.A.; Mottot, M.; Petrequin, P.

    1986-01-01

    Influence of a prior creep or fatigue exposure on subsequent fatigue or creep properties of stainless steel type 316 L SPH has been investigated. The results obtained are used to verify the validity of time and cycle fraction rule and to obtain information on the effect of very long intermittent hold times on low cycle fatigue properties, as well as on transitory loads occurring during normal service of some structural components of LMFBR reactors. Creep and fatigue tests have been carried out at 600 0 C and under conditions yielding equal or different fatigue saturation and creep stresses. Prior creep damage levels introduced range from primary to tertiary creep, whilst those of fatigue span from 20 to 70 percent of fatigue life. In both creep-fatigue and fatigue-creep sequences in the absence of a permanent prior damage (cavitation or cracking) the subsequent resistance of 316 L-SPH to fatigue or creep is unchanged, if not improved. Thin foils prepared from the specimens confirmed these observations and showed that the dislocation substructure developed during the first mode of testing is quickly replaced by that of the second mode. Grain boundary cavitation does not occur in 316 L-SPH during creep exposures to well beyond the apparent end of secondary stage and as a result prior creep exposures up to approximately 80% of rupture life do not affect fatigue properties. Conversely, significant surface cracks were found in the prior fatigue tested specimens after above about 50% life. In the presence of such cracks the subsequent creep damage was localized at the tip of the main crack and the remaining creep life was found to be usually proportional to the effective specimen cross section. Creep and fatigue sequential damage are not necessarily additive and this type of loadings are in general less severe than the repeated creep-fatigue cycling. 17 refs.

  16. A proposal of predictive methods of crack propagation life and remaining life of structural metal under creep-fatigue interacted conditions by use of X-ray profile analysis

    International Nuclear Information System (INIS)

    Ohnami, M.; Sakane, M.; Nishino, S.

    1987-01-01

    The following two series of studies are described: One is crack propagation life prediction in high-temperature low-cycle fatigue tests under triangular and trapezoidal strain or stress waves for austenitic stainless steel by X-ray fractography. Another is remaining life prediction of the steel under creep-fatigue interacted conditions by applying the concept of the remaining life diagram and X-ray profile analysis. Particle size and microstrain obtained by X-ray profile analysis were effective nondestructive parameters for estimating crack propagation life and remaining life in creep-fatigue interaction

  17. Evaluation of creep-fatigue/ environment interaction in Ni-base wrought alloys for HTGR application

    International Nuclear Information System (INIS)

    Hattori, Hiroshi; Kitagawa, Masaki; Ohtomo, Akira

    1986-01-01

    High Temperature Gas-cooled Reactor (HTGR) systems should be designed based on the high temperature structural strength design procedures. On the development of design code, the determination of failure criteria under cyclic loading and severe environments is one of the most important items. By using the previous experimental data for Ni-base wrought alloys, Inconel 617 and Hastelloy XR, several evaluation methods for creep-fatigue interaction were examined for their capability to predict their cyclic loading behavior for HTGR application. At first, the strainrange partitioning method, the frequency modified damage function and the linear damage summation rule were discussed. However, these methods were not satisfactory with the above experimental results. Thus, in this paper, a new fracture criterion, which is a modification of the linear damage summation rule, is proposed based on the experimental data. In this criterion, fracture is considered to occur when the sum of the fatigue damage, which is the function of the applied cyclic strain magnitude, and the modified creep damage, which is the function of the applied cyclic stress magnitude (determined as time devided by cyclic creep rupture time reflecting difference of creep damages by tensile creep and compressive creep), reaches a constant value. This criterion was successfully applied to the life prediction of materials at HTGR temperatures. (author)

  18. Creep-fatigue assessment of a thermina test specimen using the R5 procedure

    International Nuclear Information System (INIS)

    Booth, P.; Budden, P.J.; Bate, S.K.

    1997-01-01

    A creep-fatigue life assessment of an axisymmetric 316 stainless steel test specimen under constant mechanical and cyclic thermal shock loading using the R5 Procedure is described in this paper. This test was carried out at CEA, France, and formed part of the 'Thermina' series. Stress analysis has been carried out using both full inelastic finite element analysis and also the simplified shakedown methods, based on elastic calculation, within R5. The estimates of strain range and the stress at the start of the creep dwell have then been used with R5 to estimate creep and fatigue damage per cycle and hence to make predictions of component life. The predicted lives are compared with the lives observed in the tests. The simplified R5 estimate of life, based on development of a crack of depth 200 microns, is 260 cycles using best-estimate material properties. Experimentally, cracks of depth at least 150 microns were observed in between 526 and 650 cycles, for two similar tests. The simplified R5 route therefore leads to an estimate of life which is conservative but not unduly so on this component. Detailed cyclic inelastic analysis using the ORNL constitutive model and the ABAQUS finite element code to estimate the strain range and dwell stress led to a best estimate of 618 cycles to crack initiation using R5. (author). 16 refs, 11 figs, 4 tabs

  19. Low cycle fatigue and creep fatigue behavior of alloy 617 at high temperature

    International Nuclear Information System (INIS)

    Cabet, Celine; Carroll, Laura; Wright, Richard

    2013-01-01

    Alloy 617 is the leading candidate material for an intermediate heat exchanger (IHX) application of the very high temperature nuclear reactor (VHTR), expected to have an outlet temperature as high as 950 C. Acceptance of Alloy 617 in Section III of the ASME Code for nuclear construction requires a detailed understanding of the creep-fatigue behavior. Initial creep-fatigue work on Alloy 617 suggests a more dominant role of environment with increasing temperature and/or hold times evidenced through changes in creep-fatigue crack growth mechanisms and failure life. Continuous cycle fatigue and creep-fatigue testing of Alloy 617 was conducted at 950 C and 0.3% and 0.6% total strain in air to simulate damage modes expected in a VHTR application. Continuous cycle fatigue specimens exhibited transgranular cracking. Intergranular cracking was observed in the creep-fatigue specimens and the addition of a hold time at peak tensile strain degraded the cycle life. This suggests that creep-fatigue interaction occurs and that the environment may be partially responsible for accelerating failure. (authors)

  20. Creep-fatigue damage assessment by subsequent fatigue straining

    International Nuclear Information System (INIS)

    Yaguchi, M.; Nakamura, T.; Ishikawa, A.; Asada, Y.

    1993-01-01

    A series of creep-fatigue tests has been conducted with Modified 9Cr-1Mo steel at 600 deg. C in a high vacuum environment of 0.1mPa to assess an accumulation of creep-fatigue damage. In these tests, each test specimen has been subjected to prior creep-fatigue loading followed by subsequent fatigue loading or prior fatigue loading followed by subsequent creep-fatigue loading. A linear summation of cumulative damage of fatigue and creep life fraction is smaller than unity for the former case, and larger than unity for the latter case. SEM observation was conducted and it was shown that in the case of prior creep-fatigue loading, crack mode transforms from transgranular to intergranular type with the increase of the number of cycles of prior creep-fatigue loading, while crack mode is generally intergranular in the case of prior fatigue loading. (author)

  1. Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel Part II: Plate bending test and proposal of a simplified evaluation method

    International Nuclear Information System (INIS)

    Ando, Masanori; Takaya, Shigeru

    2016-01-01

    Highlights: • Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel is proposed. • A simplified evaluation method is also proposed for the codification. • Both proposed evaluation method was validated by the plate bending test. • For codification, the local stress and strain behavior was analyzed. - Abstract: In the present study, to develop an evaluation procedure and design rules for Mod.9Cr-1Mo steel weld joints, a method for evaluating the creep-fatigue life of Mod.9Cr-1Mo steel weld joints was proposed based on finite element analysis (FEA) and a series of cyclic plate bending tests of longitudinal and horizontal seamed plates. The strain concentration and redistribution behaviors were evaluated and the failure cycles were estimated using FEA by considering the test conditions and metallurgical discontinuities in the weld joints. Inelastic FEA models consisting of the base metal, heat-affected zone and weld metal were employed to estimate the elastic follow-up behavior caused by the metallurgical discontinuities. The elastic follow-up factors determined by comparing the elastic and inelastic FEA results were determined to be less than 1.5. Based on the estimated elastic follow-up factors obtained via inelastic FEA, a simplified technique using elastic FEA was proposed for evaluating the creep-fatigue life in Mod.9Cr-1Mo steel weld joints. The creep-fatigue life obtained using the plate bending test was compared to those estimated from the results of inelastic FEA and by a simplified evaluation method.

  2. Collect Available Creep-Fatigue Data and Study Existing Creep-Fatigue Evaluation Procedures for Grade 91 and Hastelloy XR

    International Nuclear Information System (INIS)

    Asayama, Tai; Tachibana, Yukio

    2007-01-01

    This report describes the results of investigation on Task 5 of DOE/ASME Materials Project based on a contract between ASME Standards Technology, LLC (ASME ST-LLC) and Japan Atomic Energy Agency (JAEA). Task 5 is to collect available creep-fatigue data and study existing creep-fatigue evaluation procedures for Grade 91 steel and Hastelloy XR. Part I of this report is devoted to Grade 91 steel. Existing creep-fatigue data were collected (Appendix A) and analyzed from the viewpoints of establishing a creep-fatigue procedure for VHTR design. A fair amount of creep-fatigue data has been obtained and creep-fatigue phenomena have been clarified to develop design standards mainly for fast breeder reactors. Following this, existing creep-fatigue procedures were studied and it was clarified that the creep-fatigue evaluation procedure of the ASME-NH has a lot of conservatisms and they were analyzed in detail from the viewpoints of the evaluation of creep damage of material. Based on the above studies, suggestions to improve the ASME-NH procedure along with necessary research and development items were presented. Part II of this report is devoted to Hastelloy XR. Existing creep-fatigue data used for development of the high temperature structural design guideline for High Temperature Gas-cooled Reactor (HTGR) were collected. Creep-fatigue evaluation procedure in the design guideline and its application to design of the intermediate heat exchanger (IHX) for High Temperature Engineering Test Reactor (HTTR) was described. Finally, some necessary research and development items in relation to creep-fatigue evaluation for Gen IV and VHTR reactors were presented.

  3. Collect Available Creep-Fatigue Data and Study Existing Creep-Fatigue Evaluation Procedures for Grade 91 and Hastelloy XR

    Energy Technology Data Exchange (ETDEWEB)

    Tai Asayama; Yukio Tachibana

    2007-09-30

    This report describes the results of investigation on Task 5 of DOE/ASME Materials Project based on a contract between ASME Standards Technology, LLC (ASME ST-LLC) and Japan Atomic Energy Agency (JAEA). Task 5 is to collect available creep-fatigue data and study existing creep-fatigue evaluation procedures for Grade 91 steel and Hastelloy XR. Part I of this report is devoted to Grade 91 steel. Existing creep-fatigue data were collected (Appendix A) and analyzed from the viewpoints of establishing a creep-fatigue procedure for VHTR design. A fair amount of creep-fatigue data has been obtained and creep-fatigue phenomena have been clarified to develop design standards mainly for fast breeder reactors. Following this, existing creep-fatigue procedures were studied and it was clarified that the creep-fatigue evaluation procedure of the ASME-NH has a lot of conservatisms and they were analyzed in detail from the viewpoints of the evaluation of creep damage of material. Based on the above studies, suggestions to improve the ASME-NH procedure along with necessary research and development items were presented. Part II of this report is devoted to Hastelloy XR. Existing creep-fatigue data used for development of the high temperature structural design guideline for High Temperature Gas-cooled Reactor (HTGR) were collected. Creep-fatigue evaluation procedure in the design guideline and its application to design of the intermediate heat exchanger (IHX) for High Temperature Engineering Test Reactor (HTTR) was described. Finally, some necessary research and development items in relation to creep-fatigue evaluation for Gen IV and VHTR reactors were presented.

  4. Fatigue and creep-fatigue damage assessment in Ti-6AL-4V titanium alloy using IR-thermography

    International Nuclear Information System (INIS)

    Kumar, Jalaj; Kumar, Vikas; Sundara Raman, S. Ganesh

    2015-01-01

    Titanium alloys such as Ti-6Al-4V are susceptible for fatigue and creep-fatigue interaction induced damage both at ambient and high temperature conditions. These alloys are extensively used for various structural applications such as aero-engine components etc. Reliable operation of such components depends on effective damage assessment during service. For offline damage assessment, excellent NDT techniques such as eddy current, ultrasonics, radiography etc. are available. But for online damage assessment, IR-thermography is one of the most popular techniques worldwide due to its non-intrusive and non-contact nature. Hence in the present investigation, for online damage assessment of creep-fatigue and fatigue damage, IR-thermography has been used. By holding the sample at peak stress, creep-fatigue interaction effect was introduced in the sample. Thermal profiles over fatigue and creep-fatigue samples were captured using online lock-in IR-thermography. Further, thermal modeling has been performed on the experimentally evaluated IR-data using first and second laws of thermodynamics. Thermal modeling effectively captured the partitioning of hysteresis energy into thermal losses and damage energy. This damage energy is responsible for creation of damage features such as voids in these samples. The damage energy for the sample tested with hold time (creep-fatigue) was more than that without hold time (pure fatigue) sample. Microscopic investigation further validated the higher amount of damage in creep-fatigue sample than fatigue sample. (author)

  5. Creep-fatigue damage assessment by subsequent fatigue straining

    International Nuclear Information System (INIS)

    Yaguchi, Masatsugu; Nakamura, Toshiya; Ishikawa, Akiyoshi; Asada, Yasuhide

    1993-01-01

    A series of creep-fatigue tests has been conducted with Modified 9Cr-1Mo steel at 600 C in a high vacuum environment of 0.1 mPa to assess an accumulation of creep-fatigue damage. In these tests, each test specimen has been subjected to prior creep-fatigue loading followed by subsequent fatigue loading or prior fatigue loading followed by subsequent creep-fatigue loading. A linear summation of cumulative damage of fatigue and creep life fraction was smaller than unity for the former case, and larger than unity for the latter case. Scanning electron microscopic observation showed that in the case of prior creep-fatigue loading, a crack propagated from inclusions around which cavities were observed and its appearance transformed from transgranular to intergranular type with the increase of the number of cycles of prior creep-fatigue loading, while crack mode was predominantly intergranular in the case of prior fatigue loading. It was suggested that in the case of prior creep-fatigue loading, the fatigue life becomes shorter than that predicted by the linear rule due to early initiation of a crack caused from the cavity creation. In the case of prior fatigue loading, the crack propagates different courses in each loading to lead to the life fraction which is larger than unity

  6. Nondestructive evaluation of creep-fatigue damage: an interim report

    International Nuclear Information System (INIS)

    Nickell, R.E.

    1977-02-01

    In view of the uncertainties involved in designing against creep-fatigue failure and the consequences of such failures in Class 1 nuclear components that operate at elevated temperature, the possibility of intermittent or even continuous non-destructive examination of these components has been considered. In this interim report some preliminary results on magnetic force and ultrasonic evaluation of creep-fatigue damage in an LMFBR steam generator material are presented. These results indicate that the non-destructive evaluation of pure creep damage will be extremely difficult. A set of biaxial creep-fatigue tests that are designed to discriminate between various failure theories is also described

  7. On the microstructural basis of creep strength and creep-fatigue interaction in 9-12 % Cr steels for application in power plants

    Energy Technology Data Exchange (ETDEWEB)

    Chilukuru, H.

    2007-03-06

    As part of the efforts of preserving the environment it is necessary to reduce of the CO2 emissions from power plants. This can be done by increasing the plant efficiency. Research groups around the world are engaged in developing new steels capable of sustaining higher stresses and temperatures envisaged for high-efficiency power plants. Research carried out in Europe is organized within the COST Programme (Co-Operation in Science and Technology) aiming at replacing the conventional steels of type X20CrMoV121 by the new class of 9-12% Cr-steels with modified composition. The resistance of materials against deformation at elevated temperatures depends on their microstructure. Frequently in 9-12% Cr-steels improved short-term creep properties do not persist in the long-term service [1, 2, 3, 4, 5, 6]. This is related with insufficient microstructural stability. Hardening contributions in 9-12% Cr-steels come from solute atoms of the ferritic matrix, from dislocations, and from precipitates of foreign phases within the matrix. The term ''carbide stabilized substructure hardening'' of 9-12% Cr steels [7, 8] indicates that the hardening contributions are interdependent. The dislocations are the carriers of plastic deformation. They interact with each other, with solute atoms and with precipitates. The dislocation-dislocation interaction leads to formation of planar dislocation networks constituting low-angle boundaries. They form a subgrain structure within the grains. At present, a full and detailed understanding of the effects exerted by the different components of microstructure on creep strength is still lacking. The present work makes a contribution to the efforts of understanding the microstructural basis of creep strength and of creep-fatigue interaction by transmission electron microscopic structure investigations coupled with creep tests. Investigations by transmission electron microscopy (TEM) were carried out with regard to hardening by

  8. Thermal-hydraulic investigation of the creep-fatigue specimens in the IFMIF medium flux test module

    Energy Technology Data Exchange (ETDEWEB)

    Gordeev, S.; Heinzel, V.; Schleisiek, K. [Ingenieurbuero Dr.-Ing. W. Hering, Karlsruhe (Germany)

    2004-08-01

    IFMIF (international fusion materials irradiation facility) is a facility under development to irradiate fusion relevant materials. The irradiation volume is divided into three sections, the high-, medium, and low flux test module. The medium flux test module (MFTM) consists of three submodules arranged in series in the direction of the beam. The first submodule at the beam entrance side is housing several creep-fatigue specimens. Direct electrical heating is envisaged to adjust and control the desired irradiation temperature of the specimens. The main problem in designing this submodule is to reach the level of the irradiation temperature with reasonably low temperature differences in the specimens. Preliminary estimates confirmed the suitability of the envisaged design for reaching the desired irradiation temperature but did not deliver the temperature distribution in the specimens. To obtain information on this subject a series of numerical analyses was carried out using the CFD code STAR-CD. To keep the effort in the present early design phase reasonably low, the computer model of the test installation including the initial and boundary conditions were kept as simple as possible. Nevertheless, the results are a useful additional contribution to the further design and layout of the concept. The most important conclusions and recommendation on the concept variants are summarized at the end of the report. (orig.) [German] IFMIF (International Fusion Materials Irradiation Facility) ist eine in der Planung befindliche Einrichtung zur Bestrahlung von Fusionsreaktor-relevanten Materialien. Das Bestrahlungsvo-lumen gliedert sich in drei Bereiche, den Hoch-, Mittel- und Niederflusstestmodul. Das Mittelflusstestmodul (MFTM) besteht aus drei Submodulen, die in Strahlrichtung hinter-einander angeordnet sind. Im ersten Submodul auf der Strahleintrittsseite sind drei Ermue-dungsproben untergebracht. Zur Einstellung und Konstanthaltung der gewuenschten Bestrah

  9. A Comparative Evaluation of the Effect of Low Cycle Fatigue and Creep-Fatigue Interaction on Surface Morphology and Tensile Properties of 316L(N) Stainless Steel

    Science.gov (United States)

    Mariappan, K.; Shankar, Vani; Sandhya, R.; Bhaduri, A. K.; Laha, Kinkar

    2016-04-01

    In the present work, the deformation and damage evolution in 316L(N) stainless steel during low cycle fatigue (LCF) and creep-fatigue interaction (CFI) loadings have been compared by evaluating the residual tensile properties. Towards this, LCF and CFI experiments were carried out at constant strain amplitude of ±0.6 pct, strain rate of 3 × 10-3 s-1 and temperature of 873 K (600 °C). During CFI tests, 30 minutes hold period was introduced at peak tensile strain. Experiments were interrupted up to various levels of fatigue life viz. 5, 10, 30, 50, and 60 pct of the total fatigue life ( N f) under both LCF and CFI conditions. The specimens subjected to interrupted fatigue loadings were subsequently monotonically strained at the same strain rate and temperature up to fracture. Optical and scanning electron microscopy and profilometry were conducted on the untested and tested samples to elucidate the damage evolution during the fatigue cycling under both LCF and CFI conditions. The yield strength (YS) increased sharply with the progress of fatigue damage and attained saturation within 10 pct of N f under LCF condition. On the contrary, under CFI loading condition, the YS continuously increased up to 50 pct of N f, with a sharp increase of YS up to 5 pct of N f followed by a more gradual increase up to 50 pct of N f. The difference in the evolution of remnant tensile properties was correlated with the synergistic effects of the underlying deformation and damage processes such as cyclic hardening/softening, oxidation, and creep. The evolution of tensile properties with prior fatigue damage has been correlated with the change in surface roughness and other surface features estimated by surface replica technique and fractography.

  10. Multiaxial creep-fatigue rules

    International Nuclear Information System (INIS)

    Spindler, M.W.; Hales, R.; Ainsworth, R.A.

    1997-01-01

    Within the UK, a comprehensive procedure, called R5, is used to assess the high temperature response of structures. One part of R5 deals with creep-fatigue initiation, and in this paper we describe developments in this part of R5 to cover multiaxial stress states. To assess creep-fatigue, damage is written as the linear sum of fatigue and creep components. Fatigue is assessed using Miner's law with the total endurance split into initiation and growth cycles. Initiation is assessed by entering the curve of initiation cycles vs strain range using a Tresca equivalent strain range. Growth is assessed by entering the curve of growth cycles vs strain range using a Rankine equivalent strain range. The number of allowable cycles is obtained by summing the initiation and growth cycles. In this way the problem of defining an equivalent strain range applicable over a range of endurance is avoided. Creep damage is calculated using ductility exhaustion methods. In this paper we address two aspects; first, the nature of stress relaxation and, hence, accumulated creep strain in multiaxial stress fields; secondly, the effect of multiaxial stress on creep ductility. The effect of multiaxial stress state on creep ductility has been examined using experimental data and mechanistic models. Good agreement is demonstrated between an empirical description of test data and a cavity growth model, provided a simple nucleation criterion is included. A simple scaling factor is applied to uniaxial creep ductility, defined as a function of stress state. The factor is independent of the cavity growth mechanisms and yields a value of equivalent strain which can be conveniently used in determining creep damage by ductility exhaustion. (author). 14 refs, 4 figs

  11. Creep-fatigue of low cobalt superalloys

    Science.gov (United States)

    Halford, G. R.

    1982-01-01

    Testing for the low cycle fatigue and creep fatigue resistance of superalloys containing reduced amounts of cobalt is described. The test matrix employed involves a single high temperature appropriate for each alloy. A single total strain range, again appropriate to each alloy, is used in conducting strain controlled, low cycle, creep fatigue tests. The total strain range is based upon the level of straining that results in about 10,000 cycles to failure in a high frequency (0.5 Hz) continuous strain-cycling fatigue test. No creep is expected to occur in such a test. To bracket the influence of creep on the cyclic strain resistance, strain hold time tests with ore minute hold periods are introduced. One test per composition is conducted with the hold period in tension only, one in compression only, and one in both tension and compression. The test temperatures, alloys, and their cobalt compositions that are under study are given.

  12. Creep-Fatigue Damage Investigation and Modeling of Alloy 617 at High Temperatures

    Science.gov (United States)

    Tahir, Fraaz

    The Very High Temperature Reactor (VHTR) is one of six conceptual designs proposed for Generation IV nuclear reactors. Alloy 617, a solid solution strengthened Ni-base superalloy, is currently the primary candidate material for the tubing of the Intermediate Heat Exchanger (IHX) in the VHTR design. Steady-state operation of the nuclear power plant at elevated temperatures leads to creep deformation, whereas loading transients including startup and shutdown generate fatigue. A detailed understanding of the creep-fatigue interaction in Alloy 617 is necessary before it can be considered as a material for nuclear construction in ASME Boiler and Pressure Vessel Code. Current design codes for components undergoing creep-fatigue interaction at elevated temperatures require creep-fatigue testing data covering the entire range from fatigue-dominant to creep-dominant loading. Classical strain-controlled tests, which produce stress relaxation during the hold period, show a saturation in cycle life with increasing hold periods due to the rapid stress-relaxation of Alloy 617 at high temperatures. Therefore, applying longer hold time in these tests cannot generate creep-dominated failure. In this study, uniaxial isothermal creep-fatigue tests with non-traditional loading waveforms were designed and performed at 850 and 950°C, with an objective of generating test data in the creep-dominant regime. The new loading waveforms are hybrid strain-controlled and force-controlled testing which avoid stress relaxation during the creep hold. The experimental data showed varying proportions of creep and fatigue damage, and provided evidence for the inadequacy of the widely-used time fraction rule for estimating creep damage under creep-fatigue conditions. Micro-scale damage features in failed test specimens, such as fatigue cracks and creep voids, were quantified using a Scanning Electron Microscope (SEM) to find a correlation between creep and fatigue damage. Quantitative statistical

  13. ANSYS Creep-Fatigue Assessment tool for EUROFER97 components

    Directory of Open Access Journals (Sweden)

    M. Mahler

    2016-12-01

    Full Text Available The damage caused by creep-fatigue is an important factor for materials at high temperatures. For in-vessel components of fusion reactors the material EUROFER97 is a candidate for structural application where it is subjected to irradiation and cyclic thermo-mechanical loads. To be able to evaluate fusion reactor components reliably, creep-fatigue damage has to be taken into account. In the frame of Engineering Data and Design Integration (EDDI in EUROfusion Technology Work Programme rapid and easy design evaluation is very important to predict the critical regions under typical fusion reactor loading conditions. The presented Creep-Fatigue Assessment (CFA tool is based on the creep-fatigue rules in ASME Boiler Pressure Vessel Code (BPVC Section 3 Division 1 Subsection NH which was adapted to the material EUROFER97 and developed for ANSYS. The CFA tool uses the local stress, maximum elastic strain range and temperature from the elastic analysis of the component performed with ANSYS. For the assessment design fatigue and stress to rupture curves of EUROFER97 as well as isochronous stress vs. strain curves determined by a constitutive model considering irradiation influence are used to deal with creep-fatigue damage. As a result allowable number of cycles based on creep-fatigue damage interaction under given hold times and irradiation rates is obtained. This tool can be coupled with ANSYS MAPDL and ANSYS Workbench utilizing MAPDL script files.

  14. Multiaxial creep-fatigue life analysis using strainrange partitioning

    International Nuclear Information System (INIS)

    Manson, S.S.; Halford, G.R.

    1976-01-01

    Strain-Range Partitioning is a recently developed method for treating creep-fatigue interaction at elevated temperature. Most of the work to date has been on uniaxially loaded specimens, whereas practical applications often involve load multiaxiality. This paper shows how the method can be extended to treat multiaxiality through a set of rules for combining the strain components in the three principal directions. Closed hysteresis loops, as well as plastic and creep strain ratcheting, are included. An application to hold-time tests in torsion is used to illustrate the approach

  15. Microstructural Effects on Creep-Fatigue Life of Alloy 709

    Energy Technology Data Exchange (ETDEWEB)

    McMurtrey, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Carroll, Laura [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wright, Jill [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-08-01

    Creep-fatigue tests were performed on plates of Alloy 709 from various heats and processing conditions, but often with inhomogeneous microstructures. After testing, metallographic analysis was performed and the specimens were generally found to either have a uniform grain size or a bimodal grain size distribution with either isolated or groups (bands) of large grains. Creep-fatigue life was characterized with respect to the length of the grain boundary perpendicular to the stress axis, and it was found that large grains (>400 μm) tended to be detrimental to creep-fatigue life, with the exception of elongated (parallel to the stress axis) grains and some specimens that underwent additional annealing.

  16. Consistent creep and rupture properties for creep-fatigue evaluation

    International Nuclear Information System (INIS)

    Schultz, C.C.

    1978-01-01

    The currently accepted practice of using inconsistent representations of creep and rupture behaviors in the prediction of creep-fatigue life is shown to introduce a factor of safety beyond that specified in current ASME Code design rules for 304 stainless steel Class 1 nuclear components. Accurate predictions of creep-fatigue life for uniaxial tests on a given heat of material are obtained by using creep and rupture properties for that same heat of material. The use of a consistent representation of creep and rupture properties for a mininum strength heat is also shown to provide adequate predictions. The viability of using consistent properties (either actual or those of a minimum heat) to predict creep-fatigue life thus identifies significant design uses for the results of characterization tests and improved creep and rupture correlations

  17. Creep-fatigue of High Temperature Materials for VHTR: Effect of Cyclic Loading and Environment

    Energy Technology Data Exchange (ETDEWEB)

    Celine Cabet; L. Carroll; R. Wright; R. Madland

    2011-05-01

    Alloy 617 is the one of the leading candidate materials for Intermediate Heat eXchangers (IHX) of a Very High Temperature Reactor (VHTR). System start-ups and shut-downs as well as power transients will produce low cycle fatigue (LCF) loadings of components. Furthermore, the anticipated IHX operating temperature, up to 950°C, is in the range of creep so that creep-fatigue interaction, which can significantly increase the fatigue crack growth, may be one of the primary IHX damage modes. To address the needs for Alloy 617 codification and licensing, a significant creep-fatigue testing program is underway at Idaho National Laboratory. Strain controlled LCF tests including hold times up to 1800s at maximum tensile strain were conducted at total strain range of 0.3% and 0.6% in air at 950°C. Creep-fatigue testing was also performed in a simulated VHTR impure helium coolant for selected experimental conditions. The creep-fatigue tests resulted in failure times up to 1000 hrs. Fatigue resistance was significantly decreased when a hold time was added at peak stress and when the total strain was increased. The fracture mode also changed from transgranular to intergranular with introduction of a tensile hold. Changes in the microstructure were methodically characterized. A combined effect of temperature, cyclic and static loading and environment was evidenced in the targeted operating conditions of the IHX. This paper This paper reviews the data previously published by Carroll and co-workers in references 10 and 11 focusing on the role of inelastic strain accumulation and of oxidation in the initiation and propagation of surface fatigue cracks.

  18. Study on creep-fatigue evaluation procedures for high-chromium steels-Part I: Test results and life prediction based on measured stress relaxation

    International Nuclear Information System (INIS)

    Takahashi, Yukio

    2008-01-01

    Strong demand for improving thermal efficiency of power generation plants promoted the use of high-chromium steels, which have high creep strength and corrosion resistance. Aiming at cost reduction for future nuclear power plants, these materials are also regarded as candidates for structural materials, being favoured for lower thermal expansion rate compared with austenitic stainless steels. In structural design and life management of these plants, failure due to the combination of fatigue and creep damages has been considered as an important phenomenon to be evaluated, in addition to simple creep failure under sustained loading such as inner pressure. The author has been conducting a series of creep-fatigue tests for three types of high-chromium steels used in fossil power plants and the applicability of life prediction methods has been studied. It was found that the time fraction rule gives a relatively small amount of creep damage and overpredicts the failure life, whereas a simple ductility exhaustion method provides very large creep damage which leads to too conservative prediction of failure lives. A modified ductility exhaustion method developed on the re-definition of creep damage as a ductility consumer gave a moderate amount of creep damage and provided reasonable life predictability. Moreover, an empirical formula was derived which can represent the life reduction in compressive hold tests as a function of pure fatigue life and hold time

  19. Assessment of creep-fatigue damage using the UK strain based procedure

    International Nuclear Information System (INIS)

    Bate, S.K.

    1997-01-01

    The UK strain based procedures have been developed for the evaluation of damage in structures, arising from fatigue cycles and creep processes. The fatigue damage is assessed on the basis of modelling crack growth from about one grain depth to an allowable limit which represents an engineering definition of crack formation. Creep damage is based up on the exhaustion of available ductility by creep strain accumulation. The procedures are applicable only when level A and B service conditions apply, as defined in RCC-MR or ASME Code Case N47. The procedures require the components of strain to be evaluated separately, thus they may be used with either full inelastic analysis or simplified methods. To support the development of the UK strain based creep-fatigue procedures an experimental program was undertaken by NNC to study creep-fatigue interaction of structures operating at high temperature. These tests, collectively known as the SALTBATH tests considered solid cylinder and tube-plate specimens, manufactured from Type 316 stainless steel. These specimens were subjected to thermal cycles between 250 deg. C and 600 deg. C. In all the cases the thermal cycle produces tensile residual stresses during dwells at 600 deg. C. One of the tube-plate specimens was used as a benchmark for validating the strain based creep fatigue procedures and subsequently as part of a CEC co-operative study. This benchmark work is described in this paper. A thermal and inelastic stress analysis was carried out using the finite element code ABAQUS. The inelastic behaviour of the material was described using the ORNL constitutive equations. A creep fatigue assessment using the strain based procedures has been compared with an assessment using the RCC-MR inelastic rules. The analyses indicated that both the UK strain based procedures and the RCC-MR rules were conservative, but the conservatism was greater for the RCC-MR rules. (author). 8 refs, 8 figs, 4 tabs

  20. Experimental and modeling results of creep fatigue life of Inconel 617 and Haynes 230 at 850 C

    International Nuclear Information System (INIS)

    Chen, Xiang; Sokolov, Mikhail A.; Sham, Sam; Erdman, Donald L. III; Busby, Jeremy T.; Mo, Kun; Stubbins, James

    2013-01-01

    Creep fatigue testing of Ni-based superalloy Inconel 617 and Haynes 230 were conducted in the air at 850 C. Tests were performed with fully reversed axial strain control at a total strain range of 0.5%, 1.0% or 1.5% and hold time at maximum tensile strain for 3, 10 or 30 min. In addition, two creep fatigue life prediction methods, i.e. linear damage summation and frequency-modified tensile hysteresis energy modeling, were evaluated and compared with experimental results. Under all creep fatigue tests, Haynes 230 performed better than Inconel 617. Compared to the low cycle fatigue life, the cycles to failure for both materials decreased under creep fatigue test conditions. Longer hold time at maximum tensile strain would cause a further reduction in both material creep fatigue life. The linear damage summation could predict the creep fatigue life of Inconel 617 for limited test conditions, but considerably underestimated the creep fatigue life of Haynes 230. In contrast, frequency-modified tensile hysteresis energy modeling showed promising creep fatigue life prediction results for both materials.

  1. Final Report for Project 13-4791: New Mechanistic Models of Creep-Fatigue Crack Growth Interactions for Advanced High Temperature Reactor Components

    Energy Technology Data Exchange (ETDEWEB)

    Kruzic, Jamie J [Oregon State Univ., Corvallis, OR (United States); Univ. of New South Wales, Sydney, NSW (Australia); Siegmund, Thomas [Purdue Univ., West Lafayette, IN (United States); Tomar, Vikas

    2018-03-20

    This project developed and validated a novel, multi-scale, mechanism-based model to quantitatively predict creep-fatigue crack growth and failure for Ni-based Alloy 617 at 800°C. Alloy 617 is a target material for intermediate heat exchangers in Generation IV very high temperature reactor designs, and it is envisioned that this model will aid in the design of safe, long lasting nuclear power plants. The technical effectiveness of the model was shown by demonstrating that experimentally observed crack growth rates can be predicted under both steady state and overload crack growth conditions. Feasibility was considered by incorporating our model into a commercially available finite element method code, ABAQUS, that is commonly used by design engineers. While the focus of the project was specifically on an alloy targeted for Generation IV nuclear reactors, the benefits to the public are expected to be wide reaching. Indeed, creep-fatigue failure is a design consideration for a wide range of high temperature mechanical systems that rely on Ni-based alloys, including industrial gas power turbines, advanced ultra-super critical steam turbines, and aerospace turbine engines. It is envisioned that this new model can be adapted to a wide range of engineering applications.

  2. Development of a Generic Creep-Fatigue Life Prediction Model

    Science.gov (United States)

    Goswami, Tarun

    2002-01-01

    The objective of this research proposal is to further compile creep-fatigue data of steel alloys and superalloys used in military aircraft engines and/or rocket engines and to develop a statistical multivariate equation. The newly derived model will be a probabilistic fit to all the data compiled from various sources. Attempts will be made to procure the creep-fatigue data from NASA Glenn Research Center and other sources to further develop life prediction models for specific alloy groups. In a previous effort [1-3], a bank of creep-fatigue data has been compiled and tabulated under a range of known test parameters. These test parameters are called independent variables, namely; total strain range, strain rate, hold time, and temperature. The present research attempts to use these variables to develop a multivariate equation, which will be a probabilistic equation fitting a large database. The data predicted by the new model will be analyzed using the normal distribution fits, the closer the predicted lives are with the experimental lives (normal line 1 to 1 fit) the better the prediction. This will be evaluated in terms of a coefficient of correlation, R 2 as well. A multivariate equation developed earlier [3] has the following form, where S, R, T, and H have specific meaning discussed later.

  3. Creep fatigue design of FBR components

    International Nuclear Information System (INIS)

    Bhoje, S.B.; Chellapandi, P.

    1997-01-01

    This paper deals with the characteristic features of Fast Breeder Reactor (FBR) with reference to creep fatigue, current creep fatigue design approach in compliance with RCCMR (1987) design code, material data, effects of weldments and neutron irradiation, material constitutive models employed, structural analysis and further R and D required for achieving maturity in creep fatigue design of FBR components. For the analysis reported in this paper, material constitutive models developed based on ORNIb (Oak Ridge National Laboratory) and Chaboche viscoplastic theories are employed to demonstrate the potential of FBR components for higher plant temperatures and/or longer life. The results are presented for the studies carried out towards life prediction of Prototype Fast Breeder Reactor (PFBR) components. (author). 24 refs, 8 figs, 5 tabs

  4. Creep-fatigue deformation behaviour of OFHC-copper and CuCrZr alloy with different heat treatments and with and without neutron irradiation

    International Nuclear Information System (INIS)

    Singh, B.N.; Johansen, B.S.; Li, M.; Stubbins, J.F.

    2005-08-01

    The creep-fatigue interaction behaviour of a precipitation hardened CuCrZr alloy was investigated at 295 and 573 K. To determine the effect of irradiation a number of fatigue specimens were irradiated at 333 and 573 K to a dose level in the range of 0.2 - 0.3 dpa and were tested at room temperature and 573 K, respectively. The creep-fatigue deformation behaviour of OFHC-copper was also investigated but only in the unirradiated condition and at room temperature. The creep-fatigue interaction was simulated by applying a certain holdtime on both tension and compression sides of the cyclic loading with a frequency of 0.5 Hz. Holdtimes of up to 1000 seconds were used. Creep-fatigue experiments were carried out using strain, load and extension controlled modes of cyclic loading. In addition, a number of 'interrupted' creep-fatigue tests were performed on the prime aged CuCuZr specimens in the strain controlled mode with a strain amplitude of 0.5% and a holdtime of 10 seconds. The lifetimes in terms of the number of cycles to failure were determined at different strain and load amplitudes at each holdtime. Post-deformation microstructures was investigated using a transmission electron microscopy. The main results of these investigations are presented and their implications are briefly discussed in the present report. The central conclusion emerging from the present work is that the application of holdtime generally reduces the number of cycles to failure. The largest reduction was found to be in the case of OFHC-copper. Surprisingly, the magnitude of this reduction is found to be larger at lower levels of strain or stress amplitudes, particularly when the level of the stress amplitude is below the monotonic yield strength of the material. The reduction in the yield strength due to overaging heat treatments causes a substantial decrease in the number of cycles to failure at all holdtimes investigated. The increase in the yield strength due to neutron irradiation at 333 K

  5. Creep-fatigue life property of FBR high-temperature structural materials under tension-torsion loading and life evaluation method

    International Nuclear Information System (INIS)

    Ogata, Takashi; Nitta, Akito

    1994-01-01

    Creep-fatigue damage in high temperature structural components in a FBR progress under multiaxial stress condition depending on their operating conditions and configuration. Therefore, multiaxial stress effects on creep-fatigue damage evolution must be clarified to make precise creep-fatigue damage evaluation of these components. In this study, creep-fatigue tests in FBR high temperature materials such as SUS304, 316FR stainless steels and a modified 9Cr steel were conducted under biaxial stress subjecting tension-compression and torsion loading, in order to examine biaxial stress effects on failure mechanism and life property, and to discuss creep-fatigue life evaluation methods under biaxial stress. Main results obtained in this study are summarized as follows: 1. The main cracks under cyclic torsion loading propagated by shear mode in three materials. But intergranular failure was occurred in SUS304 and 316FR, and transgranular failure was observed in Mod.9Cr steel. 2. Nonlinear damage accumulation model proposed based on uniaxial creep-fatigue test results was extended to apply for creep-fatigue damage evaluation under biaxial stress state by considering the biaxial stress effects on fatigue and creep damage evolution. 3. It was confirmed that creep-fatigue life under biaxial stress could be predicted by the extended evaluation method with higher accuracy than existing methods. (author)

  6. Creep-Fatigue Behavior of Alloy 617 at 850°C

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Laura [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    Creep-fatigue deformation is expected to be a significant contributor to the potential factors that limit the useful life of the Intermediate Heat Exchanger (IHX) in the Very High Temperature Reactor (VHTR) nuclear system.[1] The IHX of a high temperature gas reactor will be subjected to a limited number of transient cycles due to start-up and shut-down operations imparting high local stresses on the component. This cycling introduces a creep-fatigue type of interaction as dwell times occur intermittently. The leading candidate alloy for the IHX is a nickel-base solid solution strengthened alloy, Alloy 617, which must safely operate near the expected reactor outlet temperature of up to 950 °C.[1] This solid solution strengthened nickel-base alloy provides an interesting creep-fatigue deformation case study because it has characteristics of two different alloy systems for which the cyclic behavior has been extensively investigated. Compositionally, it resembles nickel-base superalloys, such as Waspalloy, IN100, and IN718, with the exception of its lower levels of Al. At temperatures above 800 °C, the microstructure of Alloy 617, however, does not contain the ordered ?’ or ?’’ phases. Thus microstructurally, it is more similar to an austenitic stainless steel, such as 316 or 304, or Alloy 800H comprised of a predominantly solid solution strengthened matrix phase with a dispersion of inter- and intragranular carbides. Previous studies of the creep-fatigue behavior of Alloy 617 at 950 °C indicate that the fatigue life is reduced when a constant strain dwell is added at peak tensile strain.[2-5] This results from the combination of faster crack initiation occurring at surface-connected grain boundaries due to oxidation from the air environment along with faster, and intergranular, crack propagation resulting from the linking of extensive interior grain boundary cracking.[3] Saturation, defined as the point at which further increases in the strain

  7. Physical-Mechanism Exploration of the Low-Cycle Unified Creep-Fatigue Formulation

    Directory of Open Access Journals (Sweden)

    Dan Liu

    2017-09-01

    Full Text Available Background—Creep-fatigue behavior is identified as the incorporated effects of fatigue and creep. One class of constitutive-based models attempts to evaluate creep and fatigue separately, but the interaction of fatigue and creep is neglected. Other models treat the damage as a single component, but the complex numerical structures that result are inconvenient for engineering application. The models derived through a curve-fitting method avoid these problems. However, the method of curving fitting cannot translate the numerical formulation to underlying physical mechanisms. Need—Therefore, there is a need to develop a new creep-fatigue formulation for metal that accommodates all relevant variables and where the relationships between them are consistent with physical mechanisms of fatigue and creep. Method—In the present work, the main dependencies and relationships for the unified creep-fatigue equation were presented through exploring what the literature says about the mechanisms. Outcomes—This shows that temperature, cyclic time and grain size have significant influences on creep-fatigue behavior, and the relationships between them (such as linear relation, logarithmical relation and power-law relation are consistent with phenomena of diffusion creep and crack growth. Significantly, the numerical form of “1 − x” is presented to show the consumption of creep effect on fatigue capacity, and the introduction of the reference condition gives the threshold of creep effect. Originality—By this means, the unified creep-fatigue equation is linked to physical phenomena, where the influence of different dependencies on creep fatigue was explored and relationships shown in this equation were investigated in a microstructural level. Particularly, a physical explanation of the grain-size exponent via consideration of crack-growth planes was proposed.

  8. Advanced constitutive equations for 10 Cr forged and cast steel for steam turbines under creep fatigue and thermo-mechanical fatigue

    International Nuclear Information System (INIS)

    Ringel, M.; Roos, E.; Maile, K.; Klenk, A.

    2004-01-01

    In order to determine the material behaviour of 10Cr steels under loading conditions similar to service, multi-axial creep and creep-fatigue tests on hollow-cylinder specimens, were carried out at temperature 600 C. It could be shown, that deformation and failure behaviour under stationary creep could be described in good agreement with the experiment results. For the creep fatigue tests, a loading cycle, which represents service loads was applied. Failure of specimens under this multi-axial creep fatigue loading occurred earlier than predicted by linear damage accumulation. In order to describe the deformation and damage under creep and fatigue loading conditions, an elastic-visco-plastic constitutive equation was developed. A secondary creep rate was introduced for a better description of diffusion-controlled creep at low stresses. Modified kinematic hardening was included to describe cyclic softening behaviour of the materials. Two damage parameters for creep and fatigue were introduced and accumulation of both was determined based on comparison of experimental and numerical results. Model parameters were fitted, using a broad database of uni-axial tests. The model is capable to describe the uni-axial behaviour exactly. Simulation of multi-axial creep fatigue tests showed good agreement between experiment and calculation, too. Special consideration of damage interaction allowed a prediction of failure with less than 10% deviation. First temperature dependent modelling results were obtained by using a simple classical visco-plastic model with temperature dependent parameters. This simple approach will be developed in the near future. Especially the damage behaviour and the strength hypothesis will be included in the same way as in the isothermal case. Comparing the model results to multi-axial thermo-mechanical fatigue test data will make the validation of the model. (orig.)

  9. A knowledge based system for creep-fatigue assessment

    International Nuclear Information System (INIS)

    Holdsworth, S.R.

    1999-01-01

    A knowledge based system was developed in the BRITE-EURAM C-FAT project to store the material property information necessary to perform complex creep-fatigue assessments and to thereby improve the effectiveness of data retrieval for such purposes. The C-FAT KBS incorporates a multi-level database which is structured to contain not only 'reduced' deformation and fracture test data, but also to enable ready access to the derived parameter constants for the constitutive and model equations used in a range of assessment procedures. The data management scheme is reviewed. The C-FAT KBS also has a dynamic worked example module which allows the sensitivity of predicted lifetimes to material property input data to be evaluated by a number of procedures. Complex cycle creep-fatigue endurance predictions are particularly sensitive to the creep property data used in assessment, and this is demonstrated with reference to the results of a number of large single edge notched bend specimen feature tests performed on a 1CrMoV turbine casting steel at 550 C. (orig.)

  10. Progress Report on Long Hold Time Creep Fatigue of Alloy 617 at 850°C

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Laura Jill [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-10-01

    Alloy 617 is the leading candidate material for an intermediate heat exchanger for the very high temperature reactor. To evaluate the behavior of this material in the expected service conditions, strain-controlled cyclic tests that include long hold times up to 240 minutes at maximum tensile strain were conducted at 850°C. In terms of the total number of cycles to failure, the fatigue resistance decreased when a hold time was added at peak tensile strain. Increases in the tensile hold duration degraded the creep-fatigue resistance, at least to the investigated strain controlled hold time of up to 60 minutes at the 0.3% strain range and 240 minutes at the 1.0% strain range. The creep-fatigue deformation mode is considered relative to the lack of saturation, or continually decreasing number of cycles to failure with increasing hold times. Additionally, preliminary values from the 850°C creep-fatigue data are calculated for the creep-fatigue damage diagram and have higher values of creep damage than those from tests at 950°C.

  11. Progress Report on Long Hold Time Creep Fatigue of Alloy 617 at 850°C

    International Nuclear Information System (INIS)

    Carroll, Laura Jill

    2015-01-01

    Alloy 617 is the leading candidate material for an intermediate heat exchanger for the very high temperature reactor. To evaluate the behavior of this material in the expected service conditions, strain-controlled cyclic tests that include long hold times up to 240 minutes at maximum tensile strain were conducted at 850°C. In terms of the total number of cycles to failure, the fatigue resistance decreased when a hold time was added at peak tensile strain. Increases in the tensile hold duration degraded the creep-fatigue resistance, at least to the investigated strain controlled hold time of up to 60 minutes at the 0.3% strain range and 240 minutes at the 1.0% strain range. The creep-fatigue deformation mode is considered relative to the lack of saturation, or continually decreasing number of cycles to failure with increasing hold times. Additionally, preliminary values from the 850°C creep-fatigue data are calculated for the creep-fatigue damage diagram and have higher values of creep damage than those from tests at 950°C.

  12. A metallographic examination of structural degradation during creep-fatigue

    International Nuclear Information System (INIS)

    Hales, R.

    1979-07-01

    A series of specimens of T316 stainless steel, which had been tested under creep-fatigue conditions, has been examined by optical and scanning electron microscopy. The development of cavities which are associated with grain-boundary carbide precipitates has been recorded. These cavities increase in size and number with increasing hold time at peak tensile strain and cause the propagating fatigue crack to follow an intergranular path. At a strain range of +- 0.25% the dominant damage mechanism is due to creep damage when the tensile hold time is greater than one minute. The fatigue crack which causes final failure is nucleated at a stress raiser and it is possible that in a smooth specimen failure may occur without the nucleation of a fatigue crack at all but rather by ductile shearing. (author)

  13. Effect of nitrogen on the creep-fatigue behaviors of type 316L(N) stainless steel

    International Nuclear Information System (INIS)

    Kim, Dae Whan; Kim, Woo Gon; Ryu, Woo Seog

    2001-01-01

    Creep-fatigue tests including hold time of 10 minute at the maximum tensile strain were conducted for type 316(N) stainless steels containing different nitrogen content of 0.04 and 0.10 wt% at 600 .deg. C and 2x10 -3 /sec in air atmosphere. Creep-fatigue life was decreased with the hold time but was increased with the addition of nitrogen. Fracture modes were intergranular regardless of nitrogen content. Dislocation structures were changed from cell to planar with the addition of nitrogen. Carbides (M 23 C 6 ) were precipitated at grain boundaries and acted as the site for cavitation. Carbides were continuous in the low nitrogen content steel but discontinuous in high nitrogen content steel. The increase of creep-fatigue life with the addition of nitrogen is attributed to the distribution of carbides at grain boundaries rather than the change of dislocation structures

  14. Physical-Mechanism Exploration of the Low-Cycle Unified Creep-Fatigue Formulation

    OpenAIRE

    Dan Liu; Dirk John Pons

    2017-01-01

    Background—Creep-fatigue behavior is identified as the incorporated effects of fatigue and creep. One class of constitutive-based models attempts to evaluate creep and fatigue separately, but the interaction of fatigue and creep is neglected. Other models treat the damage as a single component, but the complex numerical structures that result are inconvenient for engineering application. The models derived through a curve-fitting method avoid these problems. However, the method of curving fit...

  15. Final report on in-reactor creep-fatigue deformation behaviour of a CuCrZr alloy: COFAT 2

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Johansen, Bjørn Sejr; Tähtinen, S.

    facilities for this purpose, in-reactor creep-fatigue tests have been performed at strain amplitudes of 0.25 and 0.35 % with a holdtime of 10s in the BR-2 reactor at Mol (Belgium). These tests were performed at the ambient temperatures of 326K and 323K. For comparison purposes corresponding out...

  16. Creep fatigue of low-cobalt superalloys: Waspalloy, PM U 700 and wrought U 700

    Science.gov (United States)

    Leis, B. N.; Rungta, R.; Hopper, A. T.

    1983-01-01

    The influence of cobalt content on the high temperature creep fatigue crack initiation resistance of three primary alloys was evaluated. These were Waspalloy, Powder U 700, and Cast U 700, with cobalt contents ranging from 0 up to 17 percent. Waspalloy was studied at 538 C whereas the U 700 was studied at 760 C. Constraints of the program required investigation at a single strain range using diametral strain control. The approach was phenomenological, using standard low cycle fatigue tests involving continuous cycling tension hold cycling, compression hold cycling, and symmetric hold cycling. Cycling in the absence of or between holds was done at 0.5 Hz, whereas holds when introduced lasted 1 minute. The plan was to allocate two specimens to the continuous cycling, and one specimen to each of the hold time conditions. Data was taken to document the nature of the cracking process, the deformation response, and the resistance to cyclic loading to the formation of small cracks and to specimen separation. The influence of cobalt content on creep fatigue resistance was not judged to be very significant based on the results generated. Specific conclusions were that the hold time history dependence of the resistance is as significant as the influence of cobalt content and increased cobalt content does not produce increased creep fatigue resistance on a one to one basis.

  17. Prediction of inelastic behavior and creep-fatigue life of perforated plates

    International Nuclear Information System (INIS)

    Igari, Toshihide; Yamauchi, Masafumi; Nomura, Shinichi.

    1992-01-01

    Prediction methods of macroscopic and local stress-strain behaviors of perforated plates in plastic and creep regime are proposed in this paper, and are applied to the creep-fatigue life prediction of perforated plates. Both equivalent-solid-plate properties corresponding to the macroscopic behavior and the stress-strain concentration around a hole were obtained by assuming the analogy between plasticity and creep and also by extending the authors' proposal in creep condition. The perforated plates which were made of Hastelloy XR were subjected to the strain-controlled cyclic test at 950degC in air in order to experimentally obtain the macroscopic behavior such as the cyclic stress-strain curve and creep-fatigue life around a hole. The results obtained are summarized as follows. (1) The macroscopic behavior of perforated plates including cyclic stress-strain behavior and relaxation is predictable by using the proposed method in this paper. (2) The creep-fatigue life around a hole can be predicted by using the proposed method for stress-strain concentration around a hole. (author)

  18. Monitoring microstructural evolution of alloy 617 with non-linear acoustics for remaining useful life prediction; multiaxial creep-fatigue and creep-ratcheting

    International Nuclear Information System (INIS)

    Lissenden, Cliff; Hassan, Tasnin; Rangari, Vijaya

    2014-01-01

    The research built upon a prior investigation to develop a unified constitutive model for design-@by-@analysis of the intermediate heat exchanger (IHX) for a very high temperature reactor (VHTR) design of next generation nuclear plants (NGNPs). Model development requires a set of failure data from complex mechanical experiments to characterize the material behavior. Therefore uniaxial and multiaxial creep-@fatigue and creep-@ratcheting tests were conducted on the nickel base Alloy 617 at 850 and 950°C. The time dependence of material behavior, and the interaction of time dependent behavior (e.g., creep) with ratcheting, which is an increase in the cyclic mean strain under load-@controlled cycling, are major concerns for NGNP design. This research project aimed at characterizing the microstructure evolution mechanisms activated in Alloy 617 by mechanical loading and dwell times at elevated temperature. The acoustic harmonic generation method was researched for microstructural characterization. It is a nonlinear acoustics method with excellent potential for nondestructive evaluation, and even online continuous monitoring once high temperature sensors become available. It is unique because it has the ability to quantitatively characterize microstructural features well before macroscale defects (e.g., cracks) form. The nonlinear acoustics beta parameter was shown to correlate with microstructural evolution using a systematic approach to handle the complexity of multiaxial creep-@fatigue and creep-@ratcheting deformation. Mechanical testing was conducted to provide a full spectrum of data for: thermal aging, tensile creep, uniaxial fatigue, uniaxial creep-@fatigue, uniaxial creep-ratcheting, multiaxial creep-fatigue, and multiaxial creep-@ratcheting. Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Optical Microscopy were conducted to correlate the beta parameter with individual microstructure mechanisms. We researched application of the

  19. Creep-fatigue life assessment of cruciform weldments using the linear matching method

    International Nuclear Information System (INIS)

    Gorash, Yevgen; Chen, Haofeng

    2013-01-01

    This paper presents a creep-fatigue life assessment of a cruciform weldment made of the steel AISI type 316N(L) and subjected to reversed bending and cyclic dwells at 550 °C using the Linear Matching Method (LMM) and considering different weld zones. The design limits are estimated by the shakedown analysis using the LMM and elastic-perfectly-plastic material model. The creep-fatigue analysis is implemented using the following material models: 1) Ramberg–Osgood model for plastic strains under saturated cyclic conditions; 2) power-law model in “time hardening” form for creep strains during primary creep stage. The number of cycles to failure N ⋆ under creep-fatigue interaction is defined by: a) relation for cycles to fatigue failure N ∗ dependent on numerical total strain range Δε tot for the fatigue damage ω f ; b) long-term strength relation for the time to creep rupture t ∗ dependent on numerical average stress σ ¯ during dwell Δt for the creep damage ω cr ; c) non-linear creep-fatigue interaction diagram for the total damage. Numerically estimated N ⋆ for different Δt and Δε tot shows good quantitative agreement with experiments. A parametric study of different dwell times Δt is used to formulate the functions for N ⋆ and residual life L ⋆ dependent on Δt and normalised bending moment M -tilde , and the corresponding contour plot intended for design applications is created. -- Highlights: ► Ramberg–Osgood model is used for plastic strains under saturated cyclic conditions. ► Power-law model in time-hardening form is used for creep strains during dwells. ► Life assessment procedure is based on time fraction rule to evaluate creep damage. ► Function for cycles to failure is dependent on dwell period and normalised moment. ► Function for FSRF dependent on dwell period takes into account the effect of creep

  20. Temperature and grain size effect on the fatigue and creep-fatigue behavior of OFHC copper and CuCrZr for fusion application

    International Nuclear Information System (INIS)

    Pan, X.; Wu, X.; Stubbins, J.

    2007-01-01

    tests at various points in the fatigue life also will be carried out so that the progression of microstructural development could be examined. In order to gain insight into the deformation process operative during creep-fatigue interaction tests, thin foils will be prepared from specimens interrupted at different points and fractured during these tests under different conditions and were examined in a transmission electron microscope (TEM). The variance between pure fatigue and creep-fatigue should be related with the different damage mechanisms (persistent slip bands damage and grain boundary damage) during the cyclic loading process. Crystal orientation and plastic deformation could be discovered by scanning electron microscope (SEM) coupled with electron backscattered diffraction (EBSD). This paper examines the underlying microstructural aspects that control both the stress relaxation process and the changes in fatigue crack initiation. This information is critical for assessing the full impact of cyclic loading with extended hold periods in near term fusion systems design. (authors)

  1. A cycle combining method for creep fatigue analysis

    International Nuclear Information System (INIS)

    Debaene, J.P.; Permezel, P.

    1987-01-01

    In codes such as RCC-Mr (2) or code case N 47, rules are written against the creep fatigue damage. During the design phase, the order of succession of transients is not known. In that case, the codes require to take the order of events which leads to the maximum damage, but they don't give the detailed rules to perform it. The method we present here consists in building the totality of possible loading histories. For each loading history we calculate the creep fatigue damage V+W. The choice of the most severe loading history is done a posteriori. In practice, we are lead to uncouple the calculation of V and W. We proceed as follows: 1. Build all the loading histories able to masimize V. 2. For each of these loading histories, maximize W. 3. Choose a posteriori the most damaging loading history. (orig./GL)

  2. Novel experiments to characterise creep-fatigue degradation in VHTR alloys

    International Nuclear Information System (INIS)

    Simpson, J.A.; Wright, J.K.; Wright, R.N.

    2015-01-01

    It is well known in energy systems that the creep lifetime of high temperature alloys is significantly degraded when a cyclic load is superimposed on components operating in the creep regime. A test method has been developed in an attempt to characterise creep-fatigue behaviour of alloys at high temperature. The test imposes a hold time during the tensile phase of a fully reversed strain-controlled low cycle fatigue test. Stress relaxation occurs during the strain-controlled hold period. This type of fatigue stress relaxation test tends to emphasise the fatigue portion of the total damage and does not necessarily represent the behaviour of a component in-service well. Several different approaches to laboratory testing of creep-fatigue at 950 deg. C have been investigated for Alloy 617, the primary candidate for application in VHTR heat exchangers. The potential for mode switching in a cyclic test from strain control to load control, to allow specimen extension by creep, has been investigated to further emphasise the creep damage. In addition, tests with a lower strain rate during loading have been conducted to examine the influence of creep damage occurring during loading. Very short constant strain hold time tests have also been conducted to examine the influence of the rapid stress relaxation that occurs at the beginning of strain holds. (authors)

  3. Creep-Fatigue Relationsihps in Electroactive Polymer Systems and Predicted Effects in an Actuator Design

    Science.gov (United States)

    Vinogradov, Aleksandra M.; Ihlefeld, Curtis M.; Henslee, Issac

    2009-01-01

    The paper concerns the time-dependent behavior of electroactive polymers (EAP) and their use in advanced intelligent structures for space exploration. Innovative actuator design for low weight and low power valves required in small plants planned for use on the moon for chemical analysis is discussed. It is shown that in-depth understanding of cyclic loading effects observed through accelerated creep rates due to creep-fatigue interaction in polymers is critical in terms of proper functioning of EAP based actuator devices. In the paper, an overview of experimental results concerning the creep properties and cyclic creep response of a thin film piezoelectric polymer polyvinylidene fluoride (PVDF) is presented. The development of a constitutive creep-fatigue interaction model to predict the durability and service life of electroactive polymers is discussed. A novel method is proposed to predict damage accumulation and fatigue life of polymers under oyclic loading conditions in the presence of creep. The study provides a basis for ongoing research initiatives at the NASA Kennedy Space Center in the pursuit of new technologies using EAP as active elements for lunar exploration systems.

  4. DETERMINATION OF THE CREEP–FATIGUE INTERACTION DIAGRAM FOR ALLOY 617

    Energy Technology Data Exchange (ETDEWEB)

    Wright, J. K.; Carroll, L. J.; Sham, T. -L.; Lybeck, N. J.; Wright, R. N.

    2016-08-01

    Alloy 617 is the leading candidate material for an intermediate heat exchanger for the very high temperature reactor. To evaluate the behavior of this material in the expected service conditions, creep-fatigue testing was performed. Testing has been performed primarily on a single heat of material at 850 and 950°C for total strain ranges of 0.3 to 1% and tensile hold times as long as 240 minutes. At 850°C, increases in the tensile hold duration degraded the creep fatigue resistance, at least to the investigated strain-controlled hold time of up to 60 minutes at the 0.3% strain range and 240 minutes at the 1.0% strain range. At 950°C, the creep-fatigue cycles to failure becomes constant with increasing hold times, indicating saturation occurs at relatively short hold times. The creep and fatigue damage fractions have been calculated and plotted on a creep-fatigue interaction D-diagram. Results from earlier creep-fatigue tests at 800 and 1000°C on an additional heat of Alloy 617 are also plotted on the D-diagram. The methodology for calculating the damage fractions will be presented, and the effects of strain rate, strain range, temperature, hold time, and strain profile (i.e. holds in tension, compression or both) on the creep-fatigue damage will be explored.

  5. Cumulative fatigue and creep-fatigue damage at 3500C on recrystallized zircaloy 4

    International Nuclear Information System (INIS)

    Brun, G.; Pelchat, J.; Floze, J.C.; Galimberti, M.

    1985-06-01

    An experimental programme undertaken by C.E.A., E.D.F. and FRAGEMA with the aim of characterizing the fatigue and creep fatigue behaviour of zircaloy-4 following annealing treatments (recrystallized, stress-delived) is in progress. The results given below concern only recrystallized material. Cyclic properties, low-cycle fatigue curves and creep behaviour laws under stresses have been established. Sequential tests of pure fatigue and creep-fatigue were performed. The cumulative life fractions at fracture depend on the sequence of leading, stress history and number of cycles of prestressing. The MINER's rule appears to be conservative with regard to a low-high loading sequence whereas it is not for the reverse high-low loading sequences. Fatigue and creep damage are not interchangeable. Pre-creep improves the fatigue resistance. Pre-fatigue improves the creep strength as long as the beneficial effect of cyclic hardening overcomes the damaging effect of surface cracking. The introduction of a tension hold time into the fatigue cycle slightly increases cyclic hardening and reduces the number of cycles to failure. For hold times of less than one hour, the sum of fatigue and creep life fractions is closed to one

  6. Long-term creep-fatigue life property of Mod.9Cr-1Mo steel for steam generator material in FBR

    International Nuclear Information System (INIS)

    Extensive research is being executed to establish creep-fatigue life evaluation methodology for Mod.9Cr-1Mo steel which is the principal candidate material of steam generators in Demonstration Fast Breeder Reactor. Previous studies showed that the features of the creep-fatigue life property of the steel are small life reduction by tensile strain hold and significant reduction in compressive hold tests due to oxidation effect. Most of the experiments, however, were conducted under relatively short-term hold conditions and the failure life properties under long-term hold conditions have not yet been clarified. In order to investigate the oxidation and long-term strain hold effects on the creep-fatigue life property, the crack propagation tests in vacuum and air conditions, and the long-term creep-fatigue tests, up to 10 hours hold time per cycle, were performed. As a result, it was found that the significant life reduction occurred by introducing the tensile strain hold longer than 1 hour because of increase of the grain boundary damage due to cavity nucleation, and that the life reduction in compressive hold was caused by acceleration of the crack propagation rate due to accumulation of the tensile strain in center of the specimen. (author)

  7. Creep and Creep-Fatigue of Alloy 617 Weldments

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Jill K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Carroll, Laura J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wright, Richard N. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-08-01

    Alloy 617 is the primary candidate material for the heat exchanger of a very high temperature gas cooled reactor intended to operate up to 950°C. While this alloy is currently qualified in the ASME Boiler and Pressure Vessel Code for non-nuclear construction, it is not currently allowed for use in nuclear designs. A draft Code Case to qualify Alloy 617 for nuclear pressure boundary applications was submitted in 1992, but was withdrawn prior to approval. Prior to withdrawal of the draft, comments were received indicating that there was insufficient knowledge of the creep and creep-fatigue behavior of Alloy 617 welds. In this report the results of recent experiments and analysis of the creep-rupture behavior of Alloy 617 welds prepared using the gas tungsten arc process with Alloy 617 filler wire. Low cycle fatigue and creep-fatigue properties of weldments are also discussed. The experiments cover a range of temperatures from 750 to 1000°C to support development of a new Code Case to qualify the material for elevated temperature nuclear design. Properties of the welded material are compared to results of extensive characterization of solution annealed plate base metal.

  8. Investigations on creep fatigue alternating load strength of nickel alloys

    International Nuclear Information System (INIS)

    Raule, G.

    1987-01-01

    On all three nickel based materials examined (IN 713 LC, IN 617 and Nimonic 86), the crack change numbers were considerably reduced by introducing stopping times. The cyclic stresses of the materials IN 713 LC and Nimonic 86 were not affected by the interposed stopping times. The material IN 617 is subject to considerably lower stresses with increasing stopping times than in alternate stressing without stopping times. The determination of equivalent stresses by Berling and Conway's method represents a suitable process for describing the creep fatigue behaviour of the materials examined, using creep results. This material behaviour can be assessed using the linear life proportion rule, if one takes into consideration that the resulting life constants are considerably affected by the method used to determine the time creep proportion. (orig./MM) [de

  9. Creep fatigue damage of large shells submitted to thermal gradients due to sodium level variations

    International Nuclear Information System (INIS)

    Debaene, J.P.; Blaix, J.C.

    1989-01-01

    The authors present the studies performed on the upper part of the single redan of SPX2 in order to reduce the starts up duration. Main emphasis is put on the creep fatigue aspect. They present the preliminary studies performed in order to improve the behavior of structures either by technological changes, or by the adaptation of the start up procedure. The elastic analysis and inelastic analyses and the creep fatigue damage results are exposed

  10. Creep-fatigue modelling in structural steels using empirical and constitutive creep methods implemented in a strip-yield model

    Science.gov (United States)

    Andrews, Benjamin J.

    The phenomena of creep and fatigue have each been thoroughly studied. More recently, attempts have been made to predict the damage evolution in engineering materials due to combined creep and fatigue loading, but these formulations have been strictly empirical and have not been used successfully outside of a narrow set of conditions. This work proposes a new creep-fatigue crack growth model based on constitutive creep equations (adjusted to experimental data) and Paris law fatigue crack growth. Predictions from this model are compared to experimental data in two steels: modified 9Cr-1Mo steel and AISI 316L stainless steel. Modified 9Cr-1Mo steel is a high-strength steel used in the construction of pressure vessels and piping for nuclear and conventional power plants, especially for high temperature applications. Creep-fatigue and pure creep experimental data from the literature are compared to model predictions, and they show good agreement. Material constants for the constitutive creep model are obtained for AISI 316L stainless steel, an alloy steel widely used for temperature and corrosion resistance for such components as exhaust manifolds, furnace parts, heat exchangers and jet engine parts. Model predictions are compared to pure creep experimental data, with satisfactory results. Assumptions and constraints inherent in the implementation of the present model are examined. They include: spatial discretization, similitude, plane stress constraint and linear elasticity. It is shown that the implementation of the present model had a non-trivial impact on the model solutions in 316L stainless steel, especially the spatial discretization. Based on these studies, the following conclusions are drawn: 1. The constitutive creep model consistently performs better than the Nikbin, Smith and Webster (NSW) model for predicting creep and creep-fatigue crack extension. 2. Given a database of uniaxial creep test data, a constitutive material model such as the one developed for

  11. Thermal stress and creep fatigue limitations in first wall design

    International Nuclear Information System (INIS)

    Majumdar, S.; Misra, B.; Harkness, S.D.

    1977-01-01

    The thermal-hydraulic performance of a lithium cooled cylindrical first wall module has been analyzed as a function of the incident neutron wall loading. Three criteria were established for the purpose of defining the maximum wall loading allowable for modules constructed of Type 316 stainless steel and a vanadium alloy. Of the three, the maximum structural temperature criterion of 750 0 C for vanadium resulted in the limiting wall loading value of 7 MW/m 2 . The second criterion limited thermal stress levels to the yield strength of the alloy. This led to the lowest wall loading value for the Type 316 stainless steel wall (1.7 MW/m 2 ). The third criterion required that the creep-fatigue characteristics of the module allow a lifetime of 10 MW-yr/m 2 . At wall temperatures of 600 0 C, this lifetime could be achieved in a stainless steel module for wall loadings less than 3.2 MW/m 2 , while the same lifetime could be achieved for much higher wall loadings in a vanadium module

  12. Modeling of creep-fatigue interaction of zirconium {alpha} under cyclic loading at 200 C; Modelisation du comportement et de l`endommagement en fatigue-fluage du zirconium {alpha} a 200C

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, C.

    1996-04-01

    The present work deals with mechanical behaviour of zirconium alpha at 200 deg. C and crack initiation prediction methods, particularly when loading conditions lead to interaction of fatigue and creep phenomena. A classical approach used to study interaction between cyclic effects and constant loading effects does not give easy understanding of experimental results. Therefore, a new approach has been developed, which allow to determine a number of cycles for crack initiation for complex structures under large loading conditions. To study influence of fatigue and creep interaction on crack initiation, a model was chosen, using a scalar variable, giving representation of the material deterioration state. The model uses a non linear cumulating effect between the damage corresponding to cyclic loads and the damage correlated to time influence. The model belongs to uncoupled approaches between damage and behaviour, which is described here by a two inelastic deformations model. This mechanical behaviour model is chosen because it allows distinction between a plastic and a viscous part in inelastic flow. Cyclic damage is function of stress amplitude and mean stress. For the peculiar sensitivity of the material to creep, a special parameter bas been defined to be critical toward creep damage. It is the kinematic term associated to state variables describing this type of hardening in the viscous mechanism. (author).

  13. French recent developments in support to rules for creep and creep-fatigue analyses

    International Nuclear Information System (INIS)

    Touboul, F.; Moulin, D.

    1997-01-01

    RCC-MR proposes Design rules for creep and creep-fatigue damage evaluation in zones with no geometrical discontinuities. Rules have been developed, based on the σ d concept, in order to consider zones with geometrical discontinuities. Rule for Weld are proposed in the paragraph relative to shell design rules and reduction coefficient due to material properties are given in Appendix A9. For fatigue analysis, last version of RCC-MR (1993) has proposed a reduction factor on fatigue curves (Jf value), derived from preliminary tests performed within European program. Studies have been carried out in order to have a better understanding of the phenomena involved in these fatigue reduction factors. Tests have been performed on large plates, with varying applied displacements, weld geometry, plate thickness, weld direction. It appears that material effect is not the only purpose to be considered but that it is necessary to think about the geometrical effect, linked to the welded zone dimensions, and the elastic follow-up effect between the two materials: base metal and weld metal. As a first approach, simplified calculations have been achieved with precise material characterization. Roche's method and Zarka method's give conservative result in comparison to tests results. (author). 3 refs, 4 tabs

  14. Final report on in-reactor creep-fatigue deformation behaviour of a CuCrZr alloy: COFAT 1

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Tähtinen, S.; Moilanen, P.

    CrZr(HT1) alloy exposed concurrently to flux of neutrons and creep-fatigue cyclic loading directly in a fission reactor. Special experimental facilities were designed and fabricated for this purpose. A number of in-reactor creep-fatigue experiments were successfully carried out in the BR-2 reactor at Mol...

  15. Flaw assessment guide for high-temperature reactor components subject to creep-fatigue loading

    International Nuclear Information System (INIS)

    Ainsworth, R.A.; Takahashi, Y.

    1990-10-01

    A high-temperature flaw assessment procedure is described. This procedure is a result of a collaborative effort between Electric Power Research Institute in the United States, Central Research Institute of Electric Power Industry in Japan, and Nuclear Electric plc in the United Kingdom. The procedure addresses preexisting defects subject to creep-fatigue loading conditions. Laws employed to calculate the crack growth per cycle are defined in terms of fracture mechanics parameters and constants related to the component material. The crack-growth laws can be integrated to calculate the remaining life of a component or to predict the amount of crack extension in a given period. Fatigue and creep crack growth per cycle are calculated separately, and the total crack extension is taken as the simple sum of the two contributions. An interaction between the two propagation modes is accounted for in the material properties in the separate calculations. In producing the procedure, limitations of the approach have been identified. 25 refs., 1 fig

  16. Creep-fatigue damage rules for advanced fast reactor design. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    1997-03-01

    The IAEA, following the recommendations of the International Working Group on Fast Reactors, convened a Technical Committee Meeting on Creep-Fatigue Damage Rules to be used in Fast Reactor Design. The objective of the meeting was to review developments in design rules for creep-fatigue conditions and to identify any areas in which further work would be desirable. The meeting was hosted by AEA Technology, Risley, and held in Manchester, United Kingdom, 11-13 June 1996. It was attended by experts from the European Commission, France, India, Japan, the Republic of Korea, the Russian Federation and the United Kingdom. Refs, figs, tabs

  17. The environment effect on creep fatigue strength for FBR high temperature structural material, Type 304 steel

    International Nuclear Information System (INIS)

    Matsubara, Masaaki; Nitta, Akito

    1988-01-01

    In order to rationalize FBR high temperature structural design, the creep fatigue strength of Type 304 stainless steel for FBR main vessel was investigated in air and vacuum. The results obtained were as follows: Independent of strain wave forms, creep fatigue lives in vacuum were longer than those in air, and especially strain wave forms of fatigue damage type had noticeably longer lives. Also, a tendency to have too much longer lives at low strain level being important for real plant condition was shown. At last, it was confirmed that cyclic deformation behavior in vacuum was coincident with that in air. (author)

  18. Application of Strainrange Partitioning to the prediction of creep-fatigue lives of AISI Types 304 and 316 stainless steel

    Science.gov (United States)

    Saltsman, J. F.; Halford, G. R.

    1977-01-01

    As a demonstration of the predictive capabilities of the method of Strainrange Partitioning, published high-temperature, low cycle, creep-fatigue test results on AISI Types 304 and 316 stainless steel were analyzed and calculated cyclic lives compared with observed lives. Predicted lives agreed with observed lives within factors of two for 76 percent, factors of three for 93 percent, and factors of four for 98 percent of the laboratory tests analyzed. Agreement between observed and predicted lives is judged satisfactory considering that the data are associated with a number of variables (two alloys, several heats and heat treatments, a range of temperatures, different testing techniques, etc.) that are not directly accounted for in the calculations.

  19. Creep-Fatigue Life Design with Various Stress and Temperature Conditions on the Basis of Lethargy Coefficient

    International Nuclear Information System (INIS)

    Park, Jung Eun; Yang, Sung Mo; Han, Jae Hee; Yu, Hyo Sun

    2011-01-01

    High temperature and stress are encounted in power plants and vehicle engines. Therefore, determination of the creep-fatigue life of a material is necessary prior to fabricating equipment. In this study, life design was determined on the basis of the lethargy coefficient for different temperatures, stress and rupture times. SP-Creep test data was compared with computed data. The SP-Creep test was performed to obtain the rupture time for X20CrMoV121 steel. The integration life equation was considered for three cases with various load, temperature and load-temperature. First, the lethargy coefficient was calculated by using the obtained rupture stress and the rupture time that were determined by carrying out the SP-Creep test. Next, life was predicted on the basis of the temperature condition. Finally, it was observed that life decreases considerably due to the coupling effect that results when fatigue and creep occur simultaneously

  20. Evaluation of hot hardness, creep, fatigue and fracture properties of zirconia ceramics by an indentation technique

    International Nuclear Information System (INIS)

    Kutty, T.R.G.; Ganguly, C.; Upadhyaya, D.D.

    1996-01-01

    Zirconia ceramics have wide range engineering applications at room and elevated temperatures. For understanding the mechanical behaviour, the indentation technique was adapted for quick evaluation of hot hardness, creep, fatigue and fracture properties. A Vicker's diamond indentor with 10 N load was employed for hot hardness and creep measurement up to 1300 deg. The fatigue data were evaluated at room temperature by repeated indentation with a constant load (10-2500N) at the same location for a dwell time of 5s until it resulted in the formation of a lateral chip on the sample surface. Thus, the number of cycles for chip formation at a specific indentation load was obtained. The fracture toughness was evaluated at room temperature with a load of 300N using a Vicker's diamond indentor. The results of hot hardness, creep, fatigue, and fracture data ol 3Y-TZP and Mg-PSZ are discussed along with their microstructural features. (authors)

  1. Creep-fatigue behaviour of the titanium alloy IMI 834 at 600 C

    International Nuclear Information System (INIS)

    Nowack, H.; Kordisch, T.

    1998-01-01

    In the present study the creep-fatigue behaviour of the titanium alloy IMI 834 at 600 C was investigated. A comparison of the crack initiation life behaviour and of the crack propagation as caused by different types of complex creep-fatigue cycles (with hold times into tension and/or into compression direction and with different loading rates into tension and/or into compression direction) showed, that a slow increase of the loadings into tension reduced the life and increased the crack velocity more than hold times at the maximum load. Furthermore, there existed environmental influences. On the basis of the experimental investigations the prediction capability of convenient crack initiation life prediction methods was evaluated. It turned out that the prediction capability of the strain range partitioning method could be improved if it was frequency modified. The prediction capability of the frequency modification method could also be improved, if mean stresses in the cycles were explicitely accounted for. In the short and long crack stage the propagation behaviour could be correlated well if the effective cyclic J-integral was used. This is of importance for damage tolerance considerations. Because the strains and the stresses at the crack tip are most important for the crack propagation behaviour, they were analysed on the basis of the finite element method. It was found that the strains and stresses differed for different types of creep-fatigue cycles. (orig.)

  2. Creep-fatigue behaviour of aluminum alloy-based metal matrix composite

    International Nuclear Information System (INIS)

    Barbera, Daniele; Chen, Haofeng; Liu, Yinghua

    2016-01-01

    Metal Matrix Composite (MMC) represents a valuable option as structural material for different type of structures and components. Despite this they struggle to become widely adopted due to expensive manufacturing process and complex microstructural behaviour. When subjected to cyclic load conditions the structural response of MMC is not trivial, and becomes even more difficult when high temperature load is involved. Different failure mechanisms would happen and they are originated by the different material properties between the fibre and surrounding matrix. Among all, the mismatch of thermal expansion coefficient is recognized to be the dominant one. The significantly differing coefficients of thermal expansion between ceramic and metal give rise to micro thermal stresses, which enhance the initiation of matrix micro cracks. Their performance under varying load and high temperature is complex, and hence it is difficult to have a clear understanding of the structural responses, especially when fatigue and creep damages become the main failures of MMCs. To improve current understanding of the relationship between creep fatigue interaction of MMCs, the history of thermal and mechanical loading, and the creep dwell period, a highly accurate but robust direct simulation technique on the basis of the Linear Matching Method (LMM) framework has been proposed in this paper, and been applied to model the fatigue and creep behaviour of MMCs. A homogenised FE model is considered in all analyses, which consist of continuous silicon carbide fibres embedded in a square 2024T3 aluminium alloy matrix array. Various factors that affect creep and fatigue behaviours of composites are analysed and discussed, including effects of the applied load level, dwell period and temperature on the MMC's performance. The effects of reversed plasticity on stress relaxation and creep deformation of MMC are investigated, and the behaviours of cyclically enhanced creep and elastic follow-up are

  3. Creep fatigue analyses of a single wall redan according to the RCC-MR

    International Nuclear Information System (INIS)

    Blaix, J.C.; Buckthorpe, D.

    1989-01-01

    This paper deals with the validation of the single wall redan (inner vessel) option for the SUPERPHENIX 2 LMFBR project, according to the requirements of the RCC-MR Code. To complete this validation, an assessment against creep-fatigue damage has been carried out using elastic and inelastic methods. This paper presents the methods used and the results obtained. The approach has been to validate the design using elastic methods and support this with inelastic analysis to show the further safety margins that are available

  4. Creep fracture and creep-fatigue fracture in ceramics and ceramic composites

    International Nuclear Information System (INIS)

    Suresh, S.

    1993-01-01

    This paper summarizes recent advances in the areas of subcritical crack growth in ceramics subjected to static and cyclic loads at elevated temperatures. Attention is devoted to the specific role of pre-existing and in-situ-formed glass films in influencing creep fracture and creep-fatigue fracture. Experimental results on the effects of cyclic frequency and load ratio, along with detailed transmission electron microscopy of crack-tip and crack-wake damage are highlighted. Some general conclusions are drawn about the dependence of high-temperature damage tolerance on interfacial glass films and about the susceptibility of ceramic materials to cyclic fatigue fracture

  5. Influence of microstructural parameters on the deformation and failure behaviour of the ODS alloy PM 2000 under creep and creep-fatigue loading

    International Nuclear Information System (INIS)

    Bothe, K.; Kussmaul, K.; Maile, K.

    1999-01-01

    The influence of grain size, manufacturing type and specimen direction (anisotropy) with respect to deformation and failure behaviour under creep, fatigue and creep-fatigue load was investigated. Thus, a basis for the correlation between microstructure and mechanical behaviour has been established. The specific damage and failure behaviour could be explained by means of the different microstructures observed. (orig.)

  6. Influence of Hold Time on Creep-Fatigue Behavior of an Advanced Austenitic Alloy

    International Nuclear Information System (INIS)

    Carroll, Mark; Carroll, Laura

    2011-01-01

    An advanced austenitic alloy, HT-UPS (high temperature-ultrafine precipitate strengthened), is a candidate material for the structural components of fast reactors and energy-conversion systems. HT-UPS provides improved creep resistance through a composition based on 316 stainless steel (SS) with additions of Ti and Nb to form nano-scale MC precipitates in the austenitic matrix. The low cycle fatigue and creep-fatigue behavior of a HT-UPS alloy has been investigated at 650 C, 1.0% total strain, and an R ratio of -1 with hold times as long as 9000 sec at peak tensile strain. The cyclic deformation response of HT-UPS is compared to that of 316 SS. The cycles to failure are similar, despite differences in peak stress profiles and the deformed microstructures. Cracking in both alloys is transgranular (initiation and propagation) in the case of continuous cycle fatigue, while the primary cracks also propagate transgranularly during creep-fatigue cycling. Internal grain boundary damage as a result of the tensile hold is present in the form of fine cracks for hold times of 3600 sec and longer and substantially more internal cracks are visible in 316 SS than HT-UPS. The dislocation substructures observed in the deformed material are different. An equiaxed cellular structure is observed in 316 SS, whereas tangles of dislocations are present at the nanoscale MC precipitates in HT-UPS and no cellular substructure is observed.

  7. Creep and Creep-Fatigue Crack Growth at Structural Discontinuities and Welds

    Energy Technology Data Exchange (ETDEWEB)

    Dr. F. W. Brust; Dr. G. M. Wilkowski; Dr. P. Krishnaswamy; Mr. Keith Wichman

    2010-01-27

    The subsection ASME NH high temperature design procedure does not admit crack-like defects into the structural components. The US NRC identified the lack of treatment of crack growth within NH as a limitation of the code and thus this effort was undertaken. This effort is broken into two parts. Part 1, summarized here, involved examining all high temperature creep-fatigue crack growth codes being used today and from these, the task objective was to choose a methodology that is appropriate for possible implementation within NH. The second part of this task, which has just started, is to develop design rules for possible implementation within NH. This second part is a challenge since all codes require step-by-step analysis procedures to be undertaken in order to assess the crack growth and life of the component. Simple rules for design do not exist in any code at present. The codes examined in this effort included R5, RCC-MR (A16), BS 7910, API 579, and ATK (and some lesser known codes). There are several reasons that the capability for assessing cracks in high temperature nuclear components is desirable. These include: (1) Some components that are part of GEN IV reactors may have geometries that have sharp corners - which are essentially cracks. Design of these components within the traditional ASME NH procedure is quite challenging. It is natural to ensure adequate life design by modeling these features as cracks within a creep-fatigue crack growth procedure. (2) Workmanship flaws in welds sometimes occur and are accepted in some ASME code sections. It can be convenient to consider these as flaws when making a design life assessment. (3) Non-destructive Evaluation (NDE) and inspection methods after fabrication are limited in the size of the crack or flaw that can be detected. It is often convenient to perform a life assessment using a flaw of a size that represents the maximum size that can elude detection. (4) Flaws that are observed using in-service detection

  8. Analytical investigation of the applicability of simplified ratchetting and creep-fatigue rules to a nozzle-to-sphere geometry

    International Nuclear Information System (INIS)

    Gwaltney, R.C.

    1982-01-01

    This paper presents an analysis of a nozzle-to-spherical-shell attachment and explores the applicability of simplified ratchetting and creep-fatigue rules to this attachment. A five-cycle inelastic analysis and creep-fatigue damage evaluation was carried out on this component. An elastic analysis also was done to provide input parameters required to apply the various rules and procedures of simplified analysis methods. Ten lines, or critical sections, were chosen for postprocessing to determine the ratchetting strain and creep-fatigue damage at both the inside and outside surfaces. At many of the 20 surface points analyzed, the inelastic analysis results did not develop a constant or decreasing pattern for the incremental strain or damage even after 5 cycles were analyzed. Failure to develop a constant or decreasing pattern was especially prevalent for creep damage. The results of the detailed inelastic analyses at the ten critical sections are compared with the results of elastic evaluations of ratchetting and creep-fatigue damage calculated according to American Society of Mechanical Engineers Boiler and Pressure Vessel Code Case N-47-13

  9. Evaluation of environmental effect on creep-fatigue of 2 1/4Cr-1Mo steel

    International Nuclear Information System (INIS)

    Yang Beinan; Ishikawa, Akiyoshi; Asada, Yasuhide.

    1991-01-01

    In the present study, a trial evaluation was made to evaluate the environmental effect of air separately from the behavior of material origin. Data with 2 1/4Cr-1Mo steel at 550degC in air were subjected to the evaluation based on data of the steel in high vacuum with a newly developed procedure using the overstress concept. An empirical expression was proposed to describe the environmental effect of air on the creep-fatigue behavior. Following conclusions were obtained in the present study on a separation of the environmental effect of air on a creep-fatigue behavior of 2 1/4Cr-1Mo steel at 550degC. 1) The environmental effect of air reduces a fatigue life, that is, it increases the time-independent damage component of the creep-fatigue. 2) The environmental effect of air brings on the frequency effect which is mainly dependent upon a strain rate or time in a compression going stroke. Other environmental effect on F-S or compression hold-time cycles depends upon the strain rate in compression. 3) The rate-time dependent damage component, that is, the creep damage is reduced by the environmental effect of air. That means a creep-fatigue life recovers in air environment. (author)

  10. Creep-fatigue propagation of semi-elliptical crack at 650 deg. C in 316L(N) stainless steel plates with or without welded joints

    International Nuclear Information System (INIS)

    Curtit, F.

    2000-01-01

    This study realised in LISN Laboratory of CEA Saclay, deals with the creep fatigue propagation of semi elliptical crack at the temperature of 650 deg C in 316L(N) stainless steel plates with or without welded joints. A vast majority of the studies on creep fatigue propagation models are based on specimen (CT) especially designed for crack propagation study. The PLAQFLU program performed in LISN laboratory deals with the application and adaptation of these models to complex crack shape, which are more representative of the cracks observed in industrial components. In this scope, we use propagation tests realised at the temperature of 650 deg C with wide plates containing semi elliptical defects. For some of them, the initial defect is machined in the middle of a welded joint, which constitute a privileged site for the crack initiation. The approach used in this study is based on global parameters of fracture mechanics. At first, tests on CT specimen are used in order to determine the propagation laws correlating the crack growth rate to the global parameters K or C * . These laws are then supposed to be intrinsic to our materials and are used to analysed the semi elliptical crack propagation. The analysis of the comportment of the crack during the hold time demonstrates the possibility to establish a correlation between the crack propagation both in the deepest and the surface point and the local value of C * . These correlations are coherent in the different points of the crack front for the different applied hold times, and they present a reasonably good agreement with the creep propagation law identified on CT specimen. The simulation of test performed on based metal specimen with a model of summation of both creep and pure fatigue crack growth gives acceptable results when the calculus of the simplified expression of C * s considers a continuous evolution of creep deformations rate during the all test. (author)

  11. An Abnormal Increase of Fatigue Life with Dwell Time during Creep-Fatigue Deformation for Directionally Solidified Ni-Based Superalloy DZ445

    Science.gov (United States)

    Ding, Biao; Ren, Weili; Deng, Kang; Li, Haitao; Liang, Yongchun

    2018-03-01

    The paper investigated the creep-fatigue behavior for directionally solidified nickel-based superalloy DZ445 at 900 °C. It is found that the fatigue life shows an abnormal increase when the dwell time exceeds a critical value during creep-fatigue deformation. The area of hysteresis loop and fractograph explain the phenomenon quite well. The shortest life corresponds to the maximal area of hysteresis loop, i. e. the maximum energy to be consumed during the creep-fatigue cycle. The fractographic observation of failed samples further supports the abnormal behavior of fatigue life.

  12. Monitoring microstructural evolution of alloy 617 with non-linear acoustics for remaining useful life prediction; multiaxial creep-fatigue and creep-ratcheting

    Energy Technology Data Exchange (ETDEWEB)

    Lissenden, Cliff [Pennsylvania State Univ., State College, PA (United States); Hassan, Tasnin [North Carolina State Univ., Raleigh, NC (United States); Rangari, Vijaya [Tuskegee Univ., Tuskegee, AL (United States)

    2014-10-30

    The research built upon a prior investigation to develop a unified constitutive model for design-­by-­analysis of the intermediate heat exchanger (IHX) for a very high temperature reactor (VHTR) design of next generation nuclear plants (NGNPs). Model development requires a set of failure data from complex mechanical experiments to characterize the material behavior. Therefore uniaxial and multiaxial creep-­fatigue and creep-­ratcheting tests were conducted on the nickel-­base Alloy 617 at 850 and 950°C. The time dependence of material behavior, and the interaction of time dependent behavior (e.g., creep) with ratcheting, which is an increase in the cyclic mean strain under load-­controlled cycling, are major concerns for NGNP design. This research project aimed at characterizing the microstructure evolution mechanisms activated in Alloy 617 by mechanical loading and dwell times at elevated temperature. The acoustic harmonic generation method was researched for microstructural characterization. It is a nonlinear acoustics method with excellent potential for nondestructive evaluation, and even online continuous monitoring once high temperature sensors become available. It is unique because it has the ability to quantitatively characterize microstructural features well before macroscale defects (e.g., cracks) form. The nonlinear acoustics beta parameter was shown to correlate with microstructural evolution using a systematic approach to handle the complexity of multiaxial creep-­fatigue and creep-­ratcheting deformation. Mechanical testing was conducted to provide a full spectrum of data for: thermal aging, tensile creep, uniaxial fatigue, uniaxial creep-­fatigue, uniaxial creep-ratcheting, multiaxial creep-fatigue, and multiaxial creep-­ratcheting. Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Optical Microscopy were conducted to correlate the beta parameter with individual microstructure mechanisms. We researched

  13. Creep-Fatigue Cracking Near the Welded Interface in Friction Welding Dissimilar Superalloys INCONEL 718 and MAR-M247

    Science.gov (United States)

    Tra, Tran Hung; Okazaki, Masakazu

    2017-08-01

    A forged INCONEL 718 and a cast MAR-M247 alloy were joined by a friction welding process. The creep-fatigue strength of this joint was investigated. The life of the joint was significantly shorter than that of the base alloys. The joint failed near the interface of the INCONEL 718 side, although the life of INCONEL 718 was longer than that of MAR-M247. To understand this behavior, the stress field in the welding was numerically analyzed using a visco-elastic model. The results suggested that triaxiality in the stress state could be promoted near the welded interface and lead to an acceleration of creep-fatigue crack nucleation.

  14. A study on creep-fatigue life analysis using a unified constitutive equation and a continuous damage law

    International Nuclear Information System (INIS)

    Hiroe, Tetsuyuki; Igari, Toshihide; Nakajima, Keiichi

    1986-01-01

    A newly developed type of life analysis is introduced using a unified constitutive equation and a continuous damage law on 2 1/4Cr - 1Mo steel at 600 deg C. the viscoplasticity theory based on total strain and overstress used for the rate effect at room temperature is extended for application to the inelastic analysis at elevated temperature, and the extended uniaxial model is shown to reproduce the inelastic stress and strain behavior with a strain rate change observed in the experiment. The incremental life prediction law is employed and its coupling with the viscoplasticity model produces both an inelastic stress-strain response and the damage accumulation, simultaneously and continuously. The life prediction for creep, fatigue and creep-fatigue loading shows good correspondence with the experimental data. (author)

  15. FY16 Progress Report on Test Results In Support Of Integrated EPP and SMT Design Methods Development

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanli [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jetter, Robert I. [RI Jetter Consulting, Pebble Beach, CA (United States); Sham, T. -L. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-08-08

    The proposed integrated Elastic Perfectly-Plastic (EPP) and Simplified Model Test (SMT) methodology consists of incorporating an SMT data-based approach for creep-fatigue damage evaluation into the EPP methodology to avoid using the creep-fatigue interaction diagram (the D diagram) and to minimize over-conservatism while properly accounting for localized defects and stress risers. To support the implementation of the proposed code rules and to verify their applicability, a series of thermomechanical tests have been initiated. This report presents the recent test results for Type 2 SMT specimens on Alloy 617, Pressurization SMT on Alloy 617, Type 1 SMT on Gr. 91, and two-bar thermal ratcheting test results on Alloy 617 with a new thermal loading profile.

  16. An effective continuum damage mechanics model for creep-fatigue life assessment of a steam turbine rotor

    International Nuclear Information System (INIS)

    JianPing, Jing; Guang, Meng; Yi, Sun; SongBo, Xia

    2003-01-01

    A nonlinear Continuum Damage Mechanics model is proposed to assess the creep-fatigue life of a steam turbine rotor, in which the effects of complex multiaxial stress and the coupling of fatigue and creep are taken into account. The nonlinear evolution of damage is also considered. The model is applied to a 600 MW steam turbine under a practical start-stop operation. The results are compared with those from the linear accumulation theory that is dominant in life assessment of steam turbine rotors at present. The comparison show that the nonlinear continuum damage mechanics model describes the accumulation and development of damage better than the linear accumulation theory

  17. Creep-fatigue crack initiation assessment on thick circumferentially notched 316L tubes under cyclic thermal shocks and uniform tension with the σd approach

    International Nuclear Information System (INIS)

    Michel, B.; Poette, C.

    1997-01-01

    For crack initiation assessment under creep fatigue loading, in high temperature Fast Reactor's components, specific approaches based on fracture mechanics analysis had to be developed. In the present paper the crack initiation assessment method proposed in the A16 document is presented. The so called ''σ d method'' is also validated on experimental results for tubular specimens with internal axisymmetric surface cracks. Experimental data are extracted from the TERFIS program carried out on a sodium test device at the CEA Cadarache. Metallurgical examinations on TERFIS specimens confirm that the initiation assessment of the ''σ d '' approach is conservative even for a different geometry than the CT specimen on which the method was set up. However, the conservatism is reduced when the creep residual stress field is relaxed during the hold time. An investigation concerning this last point is needed in order to know if relaxing the stress, when using a lower bound of the mechanical properties, always keeps a safety margin. (author). 14 refs, 10 figs, 4 tabs

  18. Failure by Creep Cracking and Creep Fatigue Interaction in Nickel Base Superalloys.

    Science.gov (United States)

    1984-01-01

    induite par cavitation. Cette derniere ne depend que de la gdomtrie, mais la premiere est une consequence du m&anisme de croissance forctWe des casites...force motrice pour la germination et la croissance des cavites aux interfaces avec les particules. force mortice qui s’ajoute a la contrainte appliquee...en interfaces metal oxyde. Nous discutons les itapes de la cinctique susceptibles de limiter Ia vitesse lorsque Ia germination et la croissance des

  19. Creep-fatigue design studies for a sodium-cooled fast reactor with tube sheet-to shell structure subjected to elevated temperature service

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Gyeong Hoi; Lee, Jae Han [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-03-15

    In this paper, creep-fatigue damage under elevated temperatures is investigated for a tube sheet-to-shell structure, which is one of the main structures under Gen-IV class 1 components. To do this, detailed step-by-step procedures, including the elastic structural analysis and the ASME-NH code application, are described for a defined representative load cycle. From the sensitivity studies for various design parameters, such as hold time duration, shell thickness, and operating temperature, it is found that a reduction of thickness can decrease the thermal bending stresses, but the negative effect is that it may increase the primary stress and enhance the creep damage. The normal operating temperature is the most significant parameter in the creep-fatigue design

  20. Study of creep-fatigue behavior in a 1000 MW rotor using a phenomenological lifetime model

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Nailong; Wang, Weizhe; Jiang, Jishen; Liu, Yingzheng [School of Mechanical Engineering, Shanghai (China)

    2017-02-15

    In this study, the phenomenological lifetime model was applied to part of an ultra-supercritical steam turbine rotor model to predict its lifetime as a post processing of the finite element method. To validate the accuracy and adaptation of the post processing program, stress strain hysteresis loops of a cylinderal model under service-like load cycle conditions in cycle N = 1 and 300 were constructed, and the comparison of the results with experimental data on the same cylinderal specimen showed them to be satisfactory. The temperature and von Mises stress distributions of the rotor during a startup-running-shutdown-natural cool process were numerically studied using ABAQUS and the damage caused by the interaction of creep and fatigue was subsequently computed and discussed. It was found that the maximum damage appeared at the inlet notch zone, with the blade groove areas and the front notch areas also suffering a large damage amplitude.

  1. Room temperature creep-fatigue response of selected copper alloys for high heat flux applications

    DEFF Research Database (Denmark)

    Li, M.; Singh, B.N.; Stubbins, J.F.

    2004-01-01

    Two copper alloys, dispersion-strengthened CuAl25 and precipitation-hardened CuCrZr, were examined under fatigue and fatigue with hold time loading conditions. Tests were carried out at room temperature and hold times were imposed at maximum tensile and maximum compressive strains. It was found...... the hold period at all applied strain levels in both tension and compression. In all cases, stresses relaxed quickly within the first few seconds of the hold period and much more gradually thereafter. The CuAl25 alloy showed a larger effect of hold time on reduction of high cycle fatigue life than did...... the CuCrZr alloy....

  2. Room temperature creep-fatigue response of selected copper alloys for high heat flux applications

    International Nuclear Information System (INIS)

    Li Meimei; Singh, B.N.; Stubbins, J.F.

    2004-01-01

    Two copper alloys, dispersion-strengthened CuAl25 and precipitation-hardened CuCrZr, were examined under fatigue and fatigue with hold time loading conditions. Tests were carried out at room temperature and hold times were imposed at maximum tensile and maximum compressive strains. It was found that hold times could be damaging even at room temperature, well below temperatures typically associated with creep. Hold times resulted in shorter fatigue lives in the high cycle fatigue, long life regime (i.e., at low strain amplitudes) than those of materials tested under the same conditions without hold times. The influence of hold times on fatigue life in the low cycle fatigue, short life regime (i.e., at high strain amplitudes) was minimal. When hold time effects were observed, fatigue lives were reduced with hold times as short as two seconds. Appreciable stress relaxation was observed during the hold period at all applied strain levels in both tension and compression. In all cases, stresses relaxed quickly within the first few seconds of the hold period and much more gradually thereafter. The CuAl25 alloy showed a larger effect of hold time on reduction of high cycle fatigue life than did the CuCrZr alloy

  3. Fatigue and creep-fatigue behaviour of high-temperature alloys for HTR-application

    International Nuclear Information System (INIS)

    Meurer, H.-P.; Breitling, H.; Grosser, E.D.

    1981-01-01

    The development of High Temperature Gas Cooled Reactors requires the evaluation of the fatigue behaviour of those alloys which have been taken into account for possible use as structural materials. Comparative fatigue tests of six wrought alloys at 850 0 C revealed differences especially at low strain ranges. The influence of the coolant gas on Incoloy 800 H and Inconel 617 resulted in an increased fatigue life and for Incoloy 800 H in changes of the deformation behaviour. Hold times introduced at maximum tensile strain reduced fatigue life considerably. The hold time data have been evaluated following the rules of ASME Code Case N 47 and design curves for inelastic and elastic analysis are suggested. (Auth.)

  4. Low cycle fatigue and creep fatigue behaviour of a 316L stainless steel

    International Nuclear Information System (INIS)

    Simon, S.; Fuentes, M.

    1993-01-01

    Application of deformation maps to the formation of damage under low cycle conditions has allowed a better understanding of the principles underlying empiric life prediction methods. This approach has proved to be particularly useful in the formulation of a modified version of the strain range partitioning method where the criterion proposed to divide the inelastic strain into its plastic and creep components has been substanciated by the introduction of a critical strain rate that marks the transition from a matrix deformation dominated regime to a grain boundary one. Development of this approach requires detailed and consistent material data. To this aim the low cycle mechanical response and structural stability through cycling of a 316L stainless steel has been investigated. Low cylce test, including hold periods at maximum tensile strain, were also conducted at 600 and 625 C. Use of the acquired data has been made to construct cyclic stress - strain and stress -relaxation curves of the material. Also its basic fatigue/fatigue equation has been obtained. (orig.) [de

  5. The interpretation of stress reductions in creep-fatigue cycles of 316 stainless steel

    International Nuclear Information System (INIS)

    Hales, R.

    1986-11-01

    A statistical analysis of stress-drop results obtained on a number of different casts of 316 stainless steel in the temperature range 550 0 C to 700 0 C is presented. In all cases the results were obtained from strain controlled fatigue tests. The equations used to describe stress relaxation here are derived from forward creep equations which describe the dependence of creep rate on time, stress and temperature. Although there is no clear correspondence between creep and stress relaxation, creep equations offer an attractive starting point. Not all the models considered exhibited the expected response to changes in temperature. A revised analysis was carried out on the assumption that stress relaxation is thermally activated according to the Arrhenius equation. Two models were found to fit the data equally well and it was not possible to choose which of these relationships is the more appropriate to describe stress relaxation of cyclically conditioned material. On the basis of the evidence both are acceptable and may be used to calculate the creep damage according to the various high temperature design codes. Whichever gives the more conservative assessment should be used until a more mechanistically based judgement can be reached. (author)

  6. Preliminary test results in support of integrated EPP and SMT design methods development

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanli [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jetter, Robert I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sham, T. -L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-02-09

    The proposed integrated Elastic Perfectly-Plastic (EPP) and Simplified Model Test (SMT) methodology consists of incorporating a SMT data-based approach for creep-fatigue damage evaluation into the EPP methodology to avoid using the creep-fatigue interaction diagram (the D diagram) and to minimize over-conservatism while properly accounting for localized defects and stress risers. To support the implementation of the proposed code rules and to verify their applicability, a series of thermomechanical tests have been initiated. One test concept, the Simplified Model Test (SMT), takes into account the stress and strain redistribution in real structures by including representative follow-up characteristics in the test specimen. The second test concept is the two-bar thermal ratcheting tests with cyclic loading at high temperatures using specimens representing key features of potential component designs. This report summaries the previous SMT results on Alloy 617, SS316H and SS304H and presents the recent development on SMT approach on Alloy 617. These SMT specimen data are also representative of component loading conditions and have been used as part of the verification of the proposed integrated EPP and SMT design methods development. The previous two-bar thermal ratcheting test results on Alloy 617 and SS316H are also summarized and the new results from two bar thermal ratcheting tests on SS316H at a lower temperature range are reported.

  7. Testing strong interaction theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1979-01-01

    The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

  8. Creep-fatigue propagation of semi-elliptical crack at 650 deg. C in 316L(N) stainless steel plates with or without welded joints; Propagation de fissures semi-elliptiques en fatigue-fluage a 650 deg. C dans des plaques d'acier 316L(N) avec ou sans joints soudes

    Energy Technology Data Exchange (ETDEWEB)

    Curtit, F

    2000-07-01

    This study realised in LISN Laboratory of CEA Saclay, deals with the creep fatigue propagation of semi elliptical crack at the temperature of 650 deg C in 316L(N) stainless steel plates with or without welded joints. A vast majority of the studies on creep fatigue propagation models are based on specimen (CT) especially designed for crack propagation study. The PLAQFLU program performed in LISN laboratory deals with the application and adaptation of these models to complex crack shape, which are more representative of the cracks observed in industrial components. In this scope, we use propagation tests realised at the temperature of 650 deg C with wide plates containing semi elliptical defects. For some of them, the initial defect is machined in the middle of a welded joint, which constitute a privileged site for the crack initiation. The approach used in this study is based on global parameters of fracture mechanics. At first, tests on CT specimen are used in order to determine the propagation laws correlating the crack growth rate to the global parameters K or C{sup *}. These laws are then supposed to be intrinsic to our materials and are used to analysed the semi elliptical crack propagation. The analysis of the comportment of the crack during the hold time demonstrates the possibility to establish a correlation between the crack propagation both in the deepest and the surface point and the local value of C{sup *}. These correlations are coherent in the different points of the crack front for the different applied hold times, and they present a reasonably good agreement with the creep propagation law identified on CT specimen. The simulation of test performed on based metal specimen with a model of summation of both creep and pure fatigue crack growth gives acceptable results when the calculus of the simplified expression of C{sup *}{sub s} considers a continuous evolution of creep deformations rate during the all test. (author)

  9. Multiaxial Creep-Fatigue and Creep-Ratcheting Failures of Grade 91 and Haynes 230 Alloys Toward Addressing Design Issues of Gen IV Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Tasnim [North Carolina State Univ., Raleigh, NC (United States); Lissenden, Cliff [Penn State Univ., University Park, PA (United States); Carroll, Laura [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    The proposed research will develop systematic sets of uniaxial and multiaxial experimental data at a very high temperature (850-950°C) for Alloy 617. The loading histories to be prescribed in the experiments will induce creep-fatigue and creep-ratcheting failure mechanisms. These experimental responses will be scrutinized in order to quantify the influences of temperature and creep on fatigue and ratcheting failures. A unified constitutive model (UCM) will be developed and validated against these experimental responses. The improved UCM will be incorporated into the widely used finite element commercial software packages ANSYS. The modified ANSYS will be validated so that it can be used for evaluating the very high temperature ASME-NH design-by-analysis methodology for Alloy 617 and thereby addressing the ASME-NH design code issues.

  10. Service life prediction. Development of models for predicting the service life of power plant components subject to thermomechanical creep fatigue; Lebensdauervorhersage. Entwicklung von Modellen zur Lebensdauervorhersage von Kraftwerksbauteilen unter thermisch-mechanischer Kriechermuedungsbeanspruchung. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Cui, L.; Scholz, A. [Technische Univ. Darmstadt (Germany). Institut fuer Werkstoffkunde; Hartrott, P. von; Schlesinger, M. [Fraunhofer-Institut fuer Werkstoffmechanik (IWM), Freiburg im Breisgau (Germany)

    2009-07-01

    Extensive use is made of massive components of heat resistant and highly heat resistant materials in installations of the power and heating industry. These components are exposed to varying thermomechanical stress as a result of ramping-up and down processes. In this research project two computer-assisted methods of predicting service life until crack initiation were extended to include cases of thermomechanical multi-axis stress conducive to creep fatigue and of superposition of high-cycle stress on power plant components. Investigations were limited to rotor steel of type X12CrMoWVNbN10-1-1. Complex thermomechanical multi-axis experiments were performed on round, notched and cruciform test specimens of close-to-life dimensions in order to demonstrate by experiment the validity of these models. The results of these calculations showed an acceptable degree of agreement between experiment and simulation for both models. Calculations on earlier TMF experiments performed at IfW on hollow specimens of 1%CrMoNiV showed good predictability for both the SARA and the ThoMat programme. Calculations on experiments performed at MPA Stuttgart on model bodies consisting of the same 1%CrMoNiV showed a predictability of acceptable variability considering the complexity of the stresses involved. A further outcome of this project is that the use of SARA appears universally suitable for the construction of new plants and in the service area, while the use of ThoMat appears suited for detail optimisation in the development process.

  11. Development of system based code for integrity of FBR. Fundamental probabilistic approach, Part 1: Model calculation of creep-fatigue damage (Research report)

    International Nuclear Information System (INIS)

    Kawasaki, Nobuchika; Asayama, Tai

    2001-09-01

    Both reliability and safety have to be further improved for the successful commercialization of FBRs. At the same time, construction and operation costs need to be reduced to a same level of future LWRs. To realize compatibility among reliability, safety and, cost, the Structural Mechanics Research Group in JNC started the development of System Based Code for Integrity of FBR. This code extends the present structural design standard to include the areas of fabrication, installation, plant system design, safety design, operation and maintenance, and so on. A quantitative index is necessary to connect different partial standards in this code. Failure probability is considered as a candidate index. Therefore we decided to make a model calculation using failure probability and judge its applicability. We first investigated other probabilistic standards like ASME Code Case N-578. A probabilistic approach in the structural integrity evaluation was created based on these results, and also an evaluation flow was proposed. According to this flow, a model calculation of creep-fatigue damage was performed. This trial calculation was for a vessel in a sodium-cooled FBR. As the result of this model calculation, a crack initiation probability and a crack penetration probability were found to be effective indices. Last we discussed merits of this System Based Code, which are presented in this report. Furthermore, this report presents future development tasks. (author)

  12. Characterization of low-cycle fatigue and creep-fatigue induced damage in a 316L stainless steel

    International Nuclear Information System (INIS)

    Simon, S.; Rodriguez Ibabe, J.M.; Fuentes, M.

    1994-01-01

    The damage induced by low-cycle fatigue and low-cycle fatigue/creep of a 316L stainless steel has been quantified both at the fracture surfaces and in the bulk of the tested material. Examination of the fracture surfaces revealed that continuous fatigue produces transgranular damage, but, with the incorporation of dwell periods, into pure low-cycle fatigue cycles, an alternation of transgranular and intergranular damage regions is observed. A rationalization of both the mechanical low-cycle fatigue response of the material and the characterizing parameters of the damage induced by the deformation, for the investigated material and similar steels reported in the literature, has been performed. The predictions of the microstructural damage based relationships yielded by this approach have been examined against experimental observations. Low-cycle fatigue crack nucleation and crack propagation lives agree with those experimentally observed. Finally, a re-formulation of these relationships in terms of fracture mechanics has been attempted. The applicability of the concepts underlying this approach is critically examined. (orig.)

  13. Testing object Interactions

    NARCIS (Netherlands)

    Grüner, Andreas

    2010-01-01

    In this thesis we provide a unit testing approach for multi-purposes object-oriented programming languages in the style of Java and C#. Our approach includes the definition of a test specification language which results from extending the programming language with new designated specification

  14. Materials interaction test summary description

    International Nuclear Information System (INIS)

    Krogness, J.C.

    1980-01-01

    The Materials Interaction Test is designed to provide early scoping data on host rock performance and interaction between nuclear waste canister materials and host repository media under conditions representative of expected disposal environments. Capsules containing these materials were put in a spent fuel assembly and subsequently placed in a disposal test to study behavior in a low-level radiation environment at temperatures expected to range between 300 and 400 0 F. Thermal control capsules are being exposed in laboratory furnaces to allow a determination and separation of thermal and radiation effects. Post-test specimen examinations are planned to determine material property changes and interaction effects and provide data for understanding the effectiveness of host rock, canister, and cladding materials in long-term waste isolation

  15. Material test data of SUS304 welded joints

    Energy Technology Data Exchange (ETDEWEB)

    Asayama, Tai [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center; Kawakami, Tomohiro [Nuclear Energy System Incorporation, Tokyo (Japan)

    1999-10-01

    This report summarizes the material test data of SUS304 welded joints. Numbers of the data are as follows: Tensile tests 71 (Post-irradiation: 39, Others: 32), Creep tests 77 (Post-irradiation: 20, Others: 57), Fatigue tests 50 (Post-irradiation: 0), Creep-fatigue tests 14 (Post-irradiation: 0). This report consists of the printouts from 'the structural material data processing system'. (author)

  16. Precision Tests of Electroweak Interactions

    CERN Document Server

    Akhundov, Arif

    2008-01-01

    The status of the precision tests of the electroweak interactions is reviewed in this paper. An emphasis is put on the Standard Model analysis based on measurements at LEP/SLC and the Tevatron. The results of the measurements of the electroweak mixing angle in the NuTeV experiment and the future prospects are discussed.

  17. Creep, Fatigue and Fracture Behavior of Environmental Barrier Coating and SiC-SiC Ceramic Matrix Composite Systems: The Role of Environment Effects

    Science.gov (United States)

    Zhu, Dongming; Ghosn, Louis J.

    2015-01-01

    Advanced environmental barrier coating (EBC) systems for low emission SiCSiC CMC combustors and turbine airfoils have been developed to meet next generation engine emission and performance goals. This presentation will highlight the developments of NASAs current EBC system technologies for SiC-SiC ceramic matrix composite combustors and turbine airfoils, their performance evaluation and modeling progress towards improving the engine SiCSiC component temperature capability and long-term durability. Our emphasis has also been placed on the fundamental aspects of the EBC-CMC creep and fatigue behaviors, and their interactions with turbine engine oxidizing and moisture environments. The EBC-CMC environmental degradation and failure modes, under various simulated engine testing environments, in particular involving high heat flux, high pressure, high velocity combustion conditions, will be discussed aiming at quantifying the protective coating functions, performance and durability, and in conjunction with damage mechanics and fracture mechanics approaches.

  18. Interaction of high cycle fatigue with high temperature creep in superalloy single crystals

    Czech Academy of Sciences Publication Activity Database

    Lukáš, Petr; Kunz, Ludvík; Svoboda, Milan

    2002-01-01

    Roč. 93, č. 7 (2002), s. 661-665 ISSN 0044-3093 R&D Projects: GA AV ČR IAA2041002; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z2041904 Keywords : Single crystals * Creep/fatigue interaction * Persistent slip bands Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.636, year: 2002

  19. Effect of neutron irradiation on creep, fatigue and tensile properties of stainless steel type DIN 1.4948 (similar to AISI 304)

    International Nuclear Information System (INIS)

    Elen, J.D.; Vries, M.I. de; Schaff, B. van der; Staal, H.U.

    1978-03-01

    As a contribution to the German-Belgian-Dutch fast breeder project SNR-300 a mechanical testing programme is being performed at ECN to determine the effects of neutron irradiation on the mechanical properties of the DIN 1.4948 construction steel of the SNR-300 reactor vessel and internal components. Irradiations of plate and weld samples were performed at 723 K and 823 K to thermal neutron fluences of 6 x 10 18 n.cm -2 and 2 x 10 20 n.cm -2 in core positions of the High Flux Reactor at Petten at thermal to fast flux density ratios of about 0.6. Postirradiation testing comprises tensile testing at strain rates from 6 x 10 -6 s -1 to 6 s -1 , creep measurements up to 10.000 h rupture time and low cycle fatigue at strain ranges from 0.6% to 2% and a strain rate of 3 x 10 -3 s -1 . The major effect observed is high temperature embrittlement due to helium produced by the 10 B (n,α) 7 Li reaction in the 14 ppm boron containing steel used for the experiments. The creep rupture time of plate material at 823 K is reduced to 10% of its original value by irradiation to the lower fluence and the creep strength is decreased by 60 MN.m -2 . The total creep strain of weld samples is reduced to values of 0.3% to 1.5%

  20. Locating Minimal Fault Interaction in Combinatorial Testing

    Directory of Open Access Journals (Sweden)

    Wei Zheng

    2016-01-01

    Full Text Available Combinatorial testing (CT technique could significantly reduce testing cost and increase software system quality. By using the test suite generated by CT as input to conduct black-box testing towards a system, we are able to detect interactions that trigger the system’s faults. Given a test case, there may be only part of all its parameters relevant to the defects in system and the interaction constructed by those partial parameters is key factor of triggering fault. If we can locate those parameters accurately, this will facilitate the software diagnosing and testing process. This paper proposes a novel algorithm named complete Fault Interaction Location (comFIL to locate those interactions that cause system’s failures and meanwhile obtains the minimal set of target interactions in test suite produced by CT. By applying this method, testers can analyze and locate the factors relevant to defects of system more precisely, thus making the process of software testing and debugging easier and more efficient. The results of our empirical study indicate that comFIL performs better compared with known fault location techniques in combinatorial testing because of its improved effectiveness and precision.

  1. Automated Security Testing of Web Widget Interactions

    NARCIS (Netherlands)

    Bezemer, C.P.; Mesbah, A.; Van Deursen, A.

    2009-01-01

    This paper is a pre-print of: Cor-Paul Bezemer, Ali Mesbah, and Arie van Deursen. Automated Security Testing of Web Widget Interactions. In Proceedings of the 7th joint meeting of the European Software Engineering Conference and the ACM SIGSOFT Symposium on the Foundations of Software Engineering

  2. Integrating Testing and Interactive Theorem Proving

    Directory of Open Access Journals (Sweden)

    Harsh Raju Chamarthi

    2011-10-01

    Full Text Available Using an interactive theorem prover to reason about programs involves a sequence of interactions where the user challenges the theorem prover with conjectures. Invariably, many of the conjectures posed are in fact false, and users often spend considerable effort examining the theorem prover's output before realizing this. We present a synergistic integration of testing with theorem proving, implemented in the ACL2 Sedan (ACL2s, for automatically generating concrete counterexamples. Our method uses the full power of the theorem prover and associated libraries to simplify conjectures; this simplification can transform conjectures for which finding counterexamples is hard into conjectures where finding counterexamples is trivial. In fact, our approach even leads to better theorem proving, e.g. if testing shows that a generalization step leads to a false conjecture, we force the theorem prover to backtrack, allowing it to pursue more fruitful options that may yield a proof. The focus of the paper is on the engineering of a synergistic integration of testing with interactive theorem proving; this includes extending ACL2 with new functionality that we expect to be of general interest. We also discuss our experience in using ACL2s to teach freshman students how to reason about their programs.

  3. Data package for the Turkey Point material interaction test capsules

    International Nuclear Information System (INIS)

    Krogness, J.C.; Davis, R.B.

    1979-01-01

    Objective of the Materials Interaction Test (MIT) is to obtain interaction information on candidate package storage materials and geologies under prototypic temperatures in gamma and low level neutron fields. Compatibility, structural properties, and chemical transformations will be studied. The multiple test samples are contained within test capsules connected end-to-end to form a test train. Only passive instrumentation has been used to monitor temperatures and record neutron fluence. The test train contains seven capsules: three to test compatibility, two for structural tests, and two for chemical transformation studies. The materials tested are potential candidates for the spent fuel package canister and repository geologies

  4. Survey test of canister, geology, and fuel cladding material interactions

    International Nuclear Information System (INIS)

    Krogness, J.C.; Almassy, M.Y.; Cantley, D.A.; Davis, R.B.

    1979-08-01

    A series of Material Interaction Test (MIT) is being conducted. The first test is being conducted in the Dry Surface Storage Demonstration at the EMAD facility on NTS. This paper discusses details of this first test and gives a status report on the MIT series. 17 figures

  5. Interactive test tool for interoperable C-ITS development

    NARCIS (Netherlands)

    Voronov, A.; Englund, C.; Bengtsson, H.H.; Chen, L.; Ploeg, J.; Jongh, J.F.C.M. de; Sluis, H.J.D. van de

    2015-01-01

    This paper presents the architecture of an Interactive Test Tool (ITT) for interoperability testing of Cooperative Intelligent Transport Systems (C-ITS). Cooperative systems are developed by different manufacturers at different locations, which makes interoperability testing a tedious task. Up until

  6. Data package for the Turkey Point material interaction test capsules

    International Nuclear Information System (INIS)

    Krogness, J.C.; Davis, R.B.

    1980-02-01

    Objective of the test is to obtain interaction information on candidate package storage materials and geologies under prototypic temperatures in gamma and low-level neutron fields. This document provides a fabrication record of the experiment

  7. Embedment Effect test on soil-structure interaction

    International Nuclear Information System (INIS)

    Nasuda, Toshiaki; Akino, Kinji; Izumi, Masanori.

    1991-01-01

    A project consisting of laboratory test and field test has been conducted to clarify the embedment effect on soil-structure interaction. The objective of this project is to obtain the data for improving and preparing seismic analysis codes regarding the behavior of embedded reactor buildings during earthquakes. This project was planned to study the effect of soil-structure interaction using small size soil-structure models as well as the large scale models. The project was started in April, 1986, and is scheduled to end in March, 1994. The laboratory test models and field test models, and the measurement with accelerometers and others are described. As the interim results, the natural frequency and damping factor increased, and the amplitude decreased by the embedment of the test models. Some earthquakes were recorded in a soft rock site. The epicenters of the earthquakes occurred in 1989 are shown. The field tests were carried out in three sites. Two sites were used for the dynamic test with four test models having 8 m x 8 m plane size and 10 m height. One site was used for the static test with one concrete block as a specimen. Two models represent BWR type reactor buildings, and two models represent PWR type buildings. (K.I.)

  8. Interactive comparison of hypothesis tests for statistical model checking

    NARCIS (Netherlands)

    de Boer, Pieter-Tjerk; Reijsbergen, D.P.; Scheinhardt, Willem R.W.

    2015-01-01

    We present a web-based interactive comparison of hypothesis tests as are used in statistical model checking, providing users and tool developers with more insight into their characteristics. Parameters can be modified easily and their influence is visualized in real time; an integrated simulation

  9. Comparison of Methods for Estimating and Testing Latent Variable Interactions.

    Science.gov (United States)

    Moulder, Bradley C.; Algina, James

    2002-01-01

    Used simulation to compare structural equation modeling methods for estimating and testing hypotheses about an interaction between continuous variables. Findings indicate that the two-stage least squares procedure exhibited more bias and lower power than the other methods. The Jaccard-Wan procedure (J. Jaccard and C. Wan, 1995) and maximum…

  10. Sodium-fuel interaction: dropping experiments and subassembly test

    International Nuclear Information System (INIS)

    Holtbecker, H.; Schins, H.; Jorzik, E.; Klein, K.

    1978-01-01

    Nine dropping tests, which bring together 2 to 4 kg of molten UO 2 with 150 l sodium, showed the incoherency and non-violence of these thermal interactions. The pressures can be described by sodium incipient boiling and bubble collapse; the UO 2 fragmentation by thermal stress and bubble collapse impact forces. The mildness of the interaction is principally due to the slowness and incoherency of UO 2 fragmentation. This means that parametric models which assume instantaneous mixing and fragmentation are of no use for the interpretation of dropping experiments. One parametric model, the Caldarola Fuel Coolant Interaction Variable Mass model, is being coupled to the two dimensional time dependent hydrodynamic REXCO-H code. In a first step the coupling is applicated to a monodimensional geometry. A subassembly test is proposed to validate the model. In this test rapid mixing between UO 2 and sodium has to be obtained. Dispersed molten UO 2 fuel is obtained by flashing injected sodium drops inside a UO 2 melt. This flashing is theoretically explained and modelled as a superheat limited explosion. The measured sodium drop dwell times of two experiments are compared to results obtained from the mentioned theory, which is the basis of the Press 2 Code

  11. Engine cyclic durability by analysis and material testing

    Science.gov (United States)

    Kaufman, A.; Halford, G. R.

    1984-01-01

    The problem of calculating turbine engine component durability is addressed. Nonlinear, finite-element structural analyses, cyclic constitutive behavior models, and an advanced creep-fatigue life prediction method called strainrange partitioning were assessed for their applicability to the solution of durability problems in hot-section components of gas turbine engines. Three different component or subcomponent geometries are examined: a stress concentration in a turbine disk; a louver lip of a half-scale combustor linear; and a squealer tip of a first-stage high-pressure turbine blade. Cyclic structural analyses were performed for all three problems. The computed strain-temperature histories at the critical locations of the combustor linear and turbine blade components were imposed on smooth specimens in uniaxial, strain-controlled, thermomechanical fatigue tests of evaluate the structural and life analysis methods.

  12. Development of a Fluid Structures Interaction Test Technique for Fabrics

    Science.gov (United States)

    Zilliac, Gregory G.; Heineck, James T.; Schairer, Edward T.; Mosher, Robert N.; Garbeff, Theodore Joseph

    2012-01-01

    Application of fluid structures interaction (FSI) computational techniques to configurations of interest to the entry, descent and landing (EDL) community is limited by two factors - limited characterization of the material properties for fabrics of interest and insufficient experimental data to validate the FSI codes. Recently ILC Dover Inc. performed standard tests to characterize the static stress-strain response of four candidate fabrics for use in EDL applications. The objective of the tests described here is to address the need for a FSI dataset for CFD validation purposes. To reach this objective, the structural response of fabrics was measured in a very simple aerodynamic environment with well controlled boundary conditions. Two test series were undertaken. The first series covered a range of tunnel conditions and the second focused on conditions that resulted in fabric panel buckling.

  13. Jet-Surface Interaction - High Aspect Ratio Nozzle Test: Test Summary

    Science.gov (United States)

    Brown, Clifford A.

    2016-01-01

    The Jet-Surface Interaction High Aspect Ratio Nozzle Test was conducted in the Aero-Acoustic Propulsion Laboratory at the NASA Glenn Research Center in the fall of 2015. There were four primary goals specified for this test: (1) extend the current noise database for rectangular nozzles to higher aspect ratios, (2) verify data previously acquired at small-scale with data from a larger model, (3) acquired jet-surface interaction noise data suitable for creating verifying empirical noise models and (4) investigate the effect of nozzle septa on the jet-mixing and jet-surface interaction noise. These slides give a summary of the test with representative results for each goal.

  14. The Space Station Photovoltaic Panels Plasma Interaction Test Program: Test plan and results

    Science.gov (United States)

    Nahra, Henry K.; Felder, Marian C.; Sater, Bernard L.; Staskus, John V.

    1989-01-01

    The Plasma Interaction Test performed on two space station solar array panels is addressed. This includes a discussion of the test requirements, test plan, experimental set-up, and test results. It was found that parasitic current collection was insignificant (0.3 percent of the solar array delivered power). The measured arcing threshold ranged from -210 to -457 V with respect to the plasma potential. Furthermore, the dynamic response of the panels showed the panel time constant to range between 1 and 5 microsec, and the panel capacitance to be between .01 and .02 microF.

  15. The Space Station photovoltaic panels plasma interaction test program - Test plan and results

    Science.gov (United States)

    Nahra, Henry K.; Felder, Marian C.; Sater, Bernard L.; Staskus, John V.

    1990-01-01

    The plasma Interaction Test performed on two space station solar array panels is addressed. This includes a discussion of the test requirements, test plan, experimental set-up, and test results. It was found that parasitic current collection was insignificant (0.3 percent of the solar array delivered power). The measured arcing threshold ranged from -210 to -457 V with respect to the plasma potential. Furthermore, the dynamic response of the panels showed the panel time constant to range between 1 and 5 microsec, and the panel capacitance to be between .01 and .02 microF.

  16. Interaction between Harmane and Nicotinic in the Passive Avoidance Test

    Directory of Open Access Journals (Sweden)

    M Piri

    2011-01-01

    Full Text Available Introduction & Objective: A number of β-carboline alkaloids such as harmane are naturally present in the human food chain. Furthermore, some plants which contain β-carboline have behavioral effects such as hallucination. In the present study, the effect of intra-dorsal hippocampus injection of nicotinic receptor agonist on memory impairment induced by harmane was examined in mice. Materials & Methods: This study was conducted at Shahid Beheshti University in 2009. Two hundred and forty mice were anesthetized with intra-peritoneal injection of ketamine hydrochloride, plus xylazine which afterwards were placed in a stereotaxic apparatus. Two cannuale were placed in the CA1 regions of the dorsal hippocampus. All animals were allowed to recover for a total week before beginning of the behavioral testing. After that, the animals were trained in a step-down type inhibitory avoidance task and tested 24 hours after training to measure step-down latency as a scale of memory. Results: Pre-training and post-training, intra-peritoneal injection of harmane impairs inhibitory avoidance memory, but pre-testing injection of harmane did not alter memory retrieval. Pre-testing administration of high dose of nicotine (0.5 µg/mice, intra-CA1 decreased memory retrieval. On the other hand, pre-test intra-CA1 injection of ineffective doses of nicotine (0.1 and 2.5 µg/mice fully reversed harmane induced impairment of memory. Conclusion: The present results indicated that complex interaction exists between nicotinic receptor of dorsal hippocampus and the impairment of inhibitory avoidance memory induced by harmane.

  17. Tracer Interaction Effects During Partitioning Tracer Tests for NAPL Detection

    Science.gov (United States)

    Imhoff, P. T.; Pirestani, K.; Jafarpour, Y.; Spivey, K. M.

    2002-05-01

    Partitioning tracer tests have been used in laboratory and field investigations to quantify the amount of nonaqueous phase liquid (NAPL) within porous media. In these tests multiple chemical tracers are typically injected into flowing groundwater: conservative tracers react minimally with the NAPL, while non-conservative tracers partition into the NAPL and exhibit retarded transport. The mean travel times of the conservative and partitioning tracers can be used to estimate the NAPL saturation in the swept zone. When multiple tracers are injected in the system, the tracers themselves change the chemical composition of the NAPL, which may affect partitioning behavior. Although co-tracer interactions have been considered by others, there are no reports of such effects during actual partitioning tracer tests. In this study tracer partitioning was examined in static batch systems and dynamic column experiments using 2,3-dimethyl-2-butanol and 1-hexanol as partitioning tracers and trichloroethylene as the NAPL. Co-tracer effects resulted in nonlinear partitioning of 2,3-dimethyl-2-butanol in batch tests, which increased with increasing tracer concentrations. The UNIFAC model was used to predict tracer activities in the NAPL, and the resulting predictions of tracer partitioning matched the data trends. Column experiments were conducted with these same tracers, and nonlinear tracer partitioning associated with co-tracer effects resulted in underestimation of NAPL mass in some systems. If linear partitioning were assumed, a priori analysis suggested that nonlinear partitioning would result in an overestimation of NAPL saturation. We discuss these observations and suggest guidelines for avoiding co-tracer effects during partitioning tracer tests.

  18. Does interaction matter? Testing whether a confidence heuristic can replace interaction in collective decision-making

    Science.gov (United States)

    Bang, Dan; Fusaroli, Riccardo; Tylén, Kristian; Olsen, Karsten; Latham, Peter E.; Lau, Jennifer Y.F.; Roepstorff, Andreas; Rees, Geraint; Frith, Chris D.; Bahrami, Bahador

    2014-01-01

    In a range of contexts, individuals arrive at collective decisions by sharing confidence in their judgements. This tendency to evaluate the reliability of information by the confidence with which it is expressed has been termed the ‘confidence heuristic’. We tested two ways of implementing the confidence heuristic in the context of a collective perceptual decision-making task: either directly, by opting for the judgement made with higher confidence, or indirectly, by opting for the faster judgement, exploiting an inverse correlation between confidence and reaction time. We found that the success of these heuristics depends on how similar individuals are in terms of the reliability of their judgements and, more importantly, that for dissimilar individuals such heuristics are dramatically inferior to interaction. Interaction allows individuals to alleviate, but not fully resolve, differences in the reliability of their judgements. We discuss the implications of these findings for models of confidence and collective decision-making. PMID:24650632

  19. Precision test of charge independence of hadronic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Artuso, M.

    1986-10-01

    Broken symmetries are among the richest sources of information about the fundamental interactions: the renewed interest in the study of isospin non-conservation by strong forces is closely related to the effort of understanding some properties of nuclear systems in terms of their basic degrees of freedom. The hope is to be able to relate the pattern of the dynamical breaking of this symmetry to the mass spectrum of light quarks: to this purpose a more detailed phenomenological knowledge must be provided by a new generation of experiments. These considerations motivated a precision test of charge independence of strong nuclear interactions through a measurement of the parameters ..delta..A/sub y//sub 0/(theta) = A/sub y//sub 0/(theta,/sup 3/H) - A/sub y//sub 0/(theta,/sup 3/He), (the difference in analyzing power), and R identical with dsigma(theta/sup 3/H)/dsigma(theta,/sup 3/He) for the two reactions: vector p + d ..-->.. /sup 3/H + ..pi../sup +/, vector p + d ..-->.. /sup 3/He + ..pi../sup 0/. The observable ..delta..A/sub y//sub 0/ is particularly relevant as it probes the spin dependent term of the symmetry breaking interaction, on which so far almost no empirical evidence is available. The experiment has been performed at the Los Alamos Meson Physics Facility, using the N-type polarized proton beam (T/sub vector p/ = 733 MeV), and detecting the charged heavy particle in the HRS magnetic spectrometer. The final results are: ..delta..A/sub y//sub 0/ = A/sub y//sub 0/(/sup 3/H) - A/sub y//sub 0/(/sup 3/He) = 0.3930 - 0.3996 = -0.0066 +- 0.0040 +- (0.0018) and R = 2.193 +- 0.007 +- (0.027), where the first errors are statistical and the second systematic. 107 refs., 23 tabs., 63 figs.

  20. Precision test of charge independence of hadronic interactions

    International Nuclear Information System (INIS)

    Artuso, M.

    1986-10-01

    Broken symmetries are among the richest sources of information about the fundamental interactions: the renewed interest in the study of isospin non-conservation by strong forces is closely related to the effort of understanding some properties of nuclear systems in terms of their basic degrees of freedom. The hope is to be able to relate the pattern of the dynamical breaking of this symmetry to the mass spectrum of light quarks: to this purpose a more detailed phenomenological knowledge must be provided by a new generation of experiments. These considerations motivated a precision test of charge independence of strong nuclear interactions through a measurement of the parameters ΔA/sub y/ 0 (θ) = A/sub y/ 0 (θ, 3 H) - A/sub y/ 0 (θ, 3 He), (the difference in analyzing power), and R identical with dσ(θ 3 H)/dσ(θ, 3 He) for the two reactions: vector p + d → 3 H + π + , vector p + d → 3 He + π 0 . The observable ΔA/sub y/ 0 is particularly relevant as it probes the spin dependent term of the symmetry breaking interaction, on which so far almost no empirical evidence is available. The experiment has been performed at the Los Alamos Meson Physics Facility, using the N-type polarized proton beam (T/sub vector p/ = 733 MeV), and detecting the charged heavy particle in the HRS magnetic spectrometer. The final results are: ΔA/sub y/ 0 = A/sub y/ 0 ( 3 H) - A/sub y/ 0 ( 3 He) = 0.3930 - 0.3996 = -0.0066 +- 0.0040 +- (0.0018) and R = 2.193 +- 0.007 +- (0.027), where the first errors are statistical and the second systematic. 107 refs., 23 tabs., 63 figs

  1. Field tests on partial embedment effects (embedment effect tests on soil-structure interaction)

    International Nuclear Information System (INIS)

    Kurimoto, O.; Tsunoda, T.; Inoue, T.; Izumi, M.; Kusakabe, K.; Akino, K.

    1993-01-01

    A series of Model Tests of Embedment Effect on Reactor Buildings has been carried out by the Nuclear Power Engineering Corporation (NUPEC), under the sponsorship of the Ministry of International Trade and lndustry (MITI) of Japan. The nuclear reactor buildings are partially embedded due to conditions for the construction or building arrangement in Japan. It is necessary to verify the partial embedment effects by experiments and analytical studies in order to incorporate the effects in the seismic design. Forced vibration tests, therefore, were performed using a model with several types of embedment. Correlated simulation analyses were also performed and the characteristics of partial embedment effects on soil-structure interaction were evaluated. (author)

  2. Analytical study on model tests of soil-structure interaction

    International Nuclear Information System (INIS)

    Odajima, M.; Suzuki, S.; Akino, K.

    1987-01-01

    Since nuclear power plant (NPP) structures are stiff, heavy and partly-embedded, the behavior of those structures during an earthquake depends on the vibrational characteristics of not only the structure but also the soil. Accordingly, seismic response analyses considering the effects of soil-structure interaction (SSI) are extremely important for seismic design of NPP structures. Many studies have been conducted on analytical techniques concerning SSI and various analytical models and approaches have been proposed. Based on the studies, SSI analytical codes (computer programs) for NPP structures have been improved at JINS (Japan Institute of Nuclear Safety), one of the departments of NUPEC (Nuclear Power Engineering Test Center) in Japan. These codes are soil-spring lumped-mass code (SANLUM), finite element code (SANSSI), thin layered element code (SANSOL). In proceeding with the improvement of the analytical codes, in-situ large-scale forced vibration SSI tests were performed using models simulating light water reactor buildings, and simulation analyses were performed to verify the codes. This paper presents an analytical study to demonstrate the usefulness of the codes

  3. Thematic Apperception Test: an original proposal for interaction analysis

    Directory of Open Access Journals (Sweden)

    Doriana Dipaola

    2015-12-01

    Full Text Available The TAT as projective technique gives the opportunity to explore the inner world and the intra-psychic functioning, as well as the objectual representations and the prevailing thinking processes. Our hypothesis is that the TAT could also be deployed as a valid tool in the analysis of inter-personal functioning, specifically within the couple. From this assumption originates our proposal for an original methodology of TAT deployment and reading, which integrates the classical individual TAT methodology with the Common Rorschach method suggested by Willi. The goal is to experiment a parallel utilisation of the test that could contribute to the understanding of personalities and of how these intertwine in couple interaction. “In the relationship with the partner, the personality takes new shapes, given personality and character traits are strengthened, while others lose importance”, (Theodore Lidz, in Willi, 1990. The couple TAT presupposes a sequence of pictures proposed following procedures identical to the Common Rorschach ones to the single individuals at first and then to the couple. From the initial individual task follows the one of building a commonly shared history starting from the stimulus. The suggested methodology shall be exemplified through the presentation of clinical cases belonging to the research sample. The comprehension of the inter-personal dynamic, in a common task, could allow to explore the ways in which conflict expresses itself, the roles and prospects for collaboration, the “generativity” of the couple and the management of affects and anxieties in the interaction and could be successfully deployed as a tool in the context of couple counselling.

  4. Backfill-waste interactions in repository simulating tests

    International Nuclear Information System (INIS)

    Sasaki, N.; Komarneni, S.; Scheetz, B.E.; Roy, R.

    1982-01-01

    Candidate backfill materials such as montmorillonite and clinoptilolite with and without the presence of simulated nuclear waste solids such as borosilicate glass, glass ceramic, sintered ceramic and supercalcine ceramic were investigated under repository simulating conditions (=300 0 C and 30MPa). Experiments were conducted under semi-wet as well as wet repository conditions. Montmorillonite and clinoptilolite did not seem to alter under both semi-wet and wet repository conditions as determined by XRD. However, the above backfill materials reacted extensively with wastes under both conditions. They altered to feldspar (oligoclase) in the presence of borosilicate glass and to analcime in the presence of particular ceramics under both semi-wet and wet repository conditions. Alteration of montmorillonite could not be detected either in the presence of the glass ceramic or supercalcine ceramic under both repository conditions. However, clinoptilolite altered to analcime in the presence of glass ceramic or supercalcine ceramic under wet repository conditions. Reactions of backfill materials with simulated wastes immobilized waste elements such as Cs, Mo, etc., by forming new phases such as analcime, oligoclase and powellite. In fact, analyses of product solutions from interaction runs indicated that the presence of backfill materials during the alteration of waste solids served to drastically reduce the concentration of some radionuclides in solutions. These results suggest that properly selected backfills can provide the simplest and most effective chemical (or thermodynamic) engineered barrier in an intelligently designed multibarrier system. Moreover, they indicate that the μ, P, and T in the usual leach tests are such that results of such tests cannot have any value in evaluating waste form behavior under repository conditions. 3 figures, 5 tables

  5. Gene-based testing of interactions in association studies of quantitative traits.

    Directory of Open Access Journals (Sweden)

    Li Ma

    Full Text Available Various methods have been developed for identifying gene-gene interactions in genome-wide association studies (GWAS. However, most methods focus on individual markers as the testing unit, and the large number of such tests drastically erodes statistical power. In this study, we propose novel interaction tests of quantitative traits that are gene-based and that confer advantage in both statistical power and biological interpretation. The framework of gene-based gene-gene interaction (GGG tests combine marker-based interaction tests between all pairs of markers in two genes to produce a gene-level test for interaction between the two. The tests are based on an analytical formula we derive for the correlation between marker-based interaction tests due to linkage disequilibrium. We propose four GGG tests that extend the following P value combining methods: minimum P value, extended Simes procedure, truncated tail strength, and truncated P value product. Extensive simulations point to correct type I error rates of all tests and show that the two truncated tests are more powerful than the other tests in cases of markers involved in the underlying interaction not being directly genotyped and in cases of multiple underlying interactions. We applied our tests to pairs of genes that exhibit a protein-protein interaction to test for gene-level interactions underlying lipid levels using genotype data from the Atherosclerosis Risk in Communities study. We identified five novel interactions that are not evident from marker-based interaction testing and successfully replicated one of these interactions, between SMAD3 and NEDD9, in an independent sample from the Multi-Ethnic Study of Atherosclerosis. We conclude that our GGG tests show improved power to identify gene-level interactions in existing, as well as emerging, association studies.

  6. Staging scientific controversies: a gallery test on science museums' interactivity.

    Science.gov (United States)

    Yaneva, Albena; Rabesandratana, Tania Mara; Greiner, Birgit

    2009-01-01

    The "transfer" model in science communication has been addressed critically from different perspectives, while the advantages of the interactive model have been continuously praised. Yet, little is done to account for the specific role of the interactive model in communicating "unfinished science." The traditional interactive methods in museums are not sufficient to keep pace with rapid scientific developments. Interactive exchanges between laypeople and experts are thought mainly through the lens of a dialogue that is facilitated and framed by the traditional "conference room" architecture. Drawing on the results of a small-scale experiment in a gallery space, we argue for the need for a new "architecture of interaction" in museum settings based on art installation and simulation techniques, which will enhance the communication potentials of science museums and will provide conditions for a fruitful even-handed exchange of expert and lay knowledge.

  7. Java Test Driver Generation from Object-Oriented Interaction Traces

    NARCIS (Netherlands)

    M.M. Bonsangue (Marcello); F.S. de Boer (Frank); A. Gruener; M. Steffen

    2009-01-01

    htmlabstractIn the context of test-driven development for object-oriented programs, mock objects are increasingly used for unit testing. Several Java mock object frameworks exist, which all have in common that mock objects, realizing the test environment, are directly specied at the Java program

  8. Comparison of Think-Aloud and Constructive Interaction in Usability Testing with Children

    DEFF Research Database (Denmark)

    Als, Benedikte Skibsted; Jensen, Janne Jul; Skov, Mikael B.

    2005-01-01

    Constructive interaction provides natural thinking-aloud as test subjects collaborate to solve tasks. Since children may face difficulties in following instructions for a standard think-aloud test, constructive interaction has been suggested as evaluation method when usability testing with children...

  9. Discriminative deep inelastic tests of strong interaction field theories

    International Nuclear Information System (INIS)

    Glueck, M.; Reya, E.

    1979-02-01

    It is demonstrated that recent measurements of ∫ 0 1 F 2 (x, Q 2 )dx eliminate already all strong interaction field theories except QCD. A detailed study of scaling violations of F 2 (x, Q 2 ) in QCD shows their insensitivity to the gluon content of the hadron at presently measured values of Q 2 . (orig.) [de

  10. Design, testing, and delivery of an interactive graphics display subsystem

    Science.gov (United States)

    Holmes, B.

    1973-01-01

    An interactive graphics display system was designed to be used in locating components on a printed circuit card and outputting data concerning their thermal values. The manner in which this was accomplished in terms of both hardware and software is described. An analysis of the accuracy of this approach is also included.

  11. Tests for genetic interactions in type 1 diabetes

    DEFF Research Database (Denmark)

    Morahan, Grant; Mehta, Munish; James, Ian

    2011-01-01

    Interactions between genetic and environmental factors lead to immune dysregulation causing type 1 diabetes and other autoimmune disorders. Recently, many common genetic variants have been associated with type 1 diabetes risk, but each has modest individual effects. Familial clustering of type 1 ...

  12. Comparison of interactive video test performance to overall class performance in a biomechanics course

    Science.gov (United States)

    Bennett, Guinevere S.

    2018-01-01

    Objective: This study compared interactive video test performance and students' overall class performance. The hypothesis was that there would be a difference in video test performance compared to overall class performance. Methods: A total of 30 students participated in the pilot study from a master's level biomechanics course. Students completed four interactive video tests using EduCanon; content of videos included base of support, lever systems, scapulohumeral rhythm, and postural analysis. This content was reviewed with class discussion after completion of the interactive video test. The tests administered counted toward the participation portion of the final student grade. Student performance on the EduCanon interactive video test was compared to overall class grade using a paired t-test. Results: All 30 students completed the 4 EduCanon interactive video tests. Final class grades were greater compared to cumulative EduCanon test performance. There was no difference between performance using interactive video testing compared to students' overall class performance (t[29] = −1.43, p = .16). Conclusion: The results of this study did not support improved student assessment performance with incorporation of interactive video testing in the classroom environment. Continued research into new testing strategies is recommended to identify additional effective testing in the classroom. PMID:29227719

  13. Wind turbine wake interactions; results from blind tests

    Science.gov (United States)

    Krogstad, Per-Åge; Sætran, Lars

    2015-06-01

    Results from three "Blind test" Workshops on wind turbine wake modeling are presented. While the first "Blind test" (BT1, 2011) consisted of a single model turbine located in a large wind tunnel, the complexity was increased for each new test in order to see how various models performed. Thus the next "Blind test" (BT2, 2012) had two turbines mounted in-line. This is a crucial test for models intended to predict turbine performances in a wind farm. In the last "Blind test" (BT3, 2013) the two turbines were again mounted in-line, but offset sideways so that the rotor of the downstream turbine only intersected half the wake from the upstream turbine. This case produces high dynamic loads and strong asymmetry in the wake. For each "Blind test" the turbine geometry and wind tunnel environment was specified and the participants were asked to predict the turbine performances, as well as the wake development to five diameters downstream of the second turbine. For the first two tests axisymmetry could be assumed if the influence of the towers was neglected. This was not possible in BT3 and therefore only fully 3D methods could be applied. In all tests the prediction scatter was surprisingly high.

  14. The Interaction of Humor and Anxiety in Academic Test Situations.

    Science.gov (United States)

    Brown, Alan S.; Itzig, Jerry M.

    The effects of humorous test questions on test performance of high and low-anxious college students was investigated. It was hypothesized that humor should reduce the anxiety level of high-anxious subjects, and thus improve their performance, while having little effect on low-anxious subjects. Students were assigned to a low or high-anxious group…

  15. Persistence Heterogeneity Testing in Panels with Interactive Fixed Effects

    DEFF Research Database (Denmark)

    Ergemen, Yunus Emre; Velasco, Carlos

    for correction. We develop tests of homogeneity of dynamics, including the degree of integration, that have no trivial power under local departures from the null hypothesis of a non-negligible fraction of cross-section units. A simulation study shows that our estimates and test have good performance even...

  16. Contrast media: interactions with other drugs and clinical tests

    International Nuclear Information System (INIS)

    Morcos, Sameh K.; Exley, C.M.; Thomsen, Henrik S.

    2005-01-01

    Many patients with multiple medical problems who are receiving a variety of drugs are investigated with imaging techniques which require intravascular contrast media. The Contrast Media Safety Committee of the European Society of Urogenital Radiology therefore decided to review the literature and to draw up simple guidelines on interactions between contrast media and other drugs. An extensive literature search was carried out and summarized in a report. Based on the available information, simple guidelines have been drawn up. The report and guidelines were discussed at the 11th European Symposium on Urogenital Radiology in Santiago de Compostela. Contrast media may interact with other drugs, and may interfere with isotope studies and biochemical measurements. Awareness of the patient drug history is important to avoid potential hazards. Simple guidelines are presented. (orig.)

  17. Tests of electroweak interactions at CERN's LEP Collider

    Science.gov (United States)

    Fearnley, T. A.

    1995-08-01

    Precision measurements of electroweak interactions at the Z0 energy are performed at four experiments at the Large Electron Positron (LEP) Collider at CERN in Geneva, Switzerland. The large amount of data obtained from 1989 until today allows detailed comparisons with the predictions made by the Standard Model. Within the experimental errors the agreement with the Standard Model is good. Fits to the LEP data allow an indirect determination of the mass of the top quark: Mt=173+12+18-13-20 GeV, assuming a Higgs boson mass of 300 GeV. The first errors reflect the experimental errors (systematic and statistical) on the measurements. The second errors correspond to the variation of the central value when varying the Higgs mass between 60 and 1000 GeV. This paper reviews the results of the measurements of electroweak interactions, and compares the results with predictions made by the Standard Model.

  18. Host-parasite interactions: a litmus test for ocean acidification?

    Science.gov (United States)

    MacLeod, Colin D; Poulin, Robert

    2012-09-01

    The effects of ocean acidification (OA) on marine species and ecosystems have received significant scientific attention in the past 10 years. However, to date, the effects of OA on host-parasite interactions have been largely ignored. As parasites play a multidimensional role in the regulation of marine population, community, and ecosystem dynamics, this knowledge gap may result in an incomplete understanding of the consequences of OA. In addition, the impact of stressors associated with OA on host-parasite interactions may serve as an indicator of future changes to the biodiversity of marine systems. This opinion article discusses the potential effects of OA on host and parasite species and proposes the use of parasites as bioindicators of OA disturbance. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Human-Robot Interaction Reconfigurable Test Environment: Optimizing the Human Interface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Human-Robot Interaction Reconfigurable Test Environment (HRI-RTE) integrates a grid-based, reconfigurable test arena and an operator workstation with...

  20. Shaking table test and analysis of embedded structure soil interaction considering input motion

    International Nuclear Information System (INIS)

    Matsushima, Y.; Mizuno, H.; Machida, N.; Sato, K.; Okano, H.

    1987-01-01

    The dynamic interaction between soil and structure is decomposed into inertial interaction (II) and kinematic interaction (KI). II denotes the interaction due to inertial force applied on foundations. KI denotes the interaction of massless foundations subjected to seismic waves. Forced vibration tests by exciters are not enough to evaluate the complete soil-structure interaction due to the lack of KI. To clarify the effects of KI on the seismic response of structure, the authors intended to carry out shaking table tests of the interaction between the soil and the embedded structure. A method to decompose II and KI is introduced which reveals the construction of embedment effects. Finally, the authors discuss the validity of three kinds of simulation analyses, that is, two-dimensional, approximate three-dimensional and rigorous three-dimensional analyses, comparing with the test results

  1. Computer-aided system for interactive psychomotor testing

    Science.gov (United States)

    Selivanova, Karina G.; Ignashchuk, Olena V.; Koval, Leonid G.; Kilivnik, Volodymyr S.; Zlepko, Alexandra S.; Sawicki, Daniel; Kalizhanova, Aliya; Zhanpeisova, Aizhan; Smailova, Saule

    2017-08-01

    Nowadays research of psychomotor actions has taken a special place in education, sports, medicine, psychology etc. Development of computer system for psychomotor testing could help solve many operational problems in psychoneurology and psychophysiology and also determine the individual characteristics of fine motor skills. This is particularly relevant issue when it comes to children, students, athletes for definition of personal and professional features. The article presents the dynamics of a developing psychomotor skills and application in the training process of means. The results of testing indicated their significant impact on psychomotor skills development.

  2. A combination test for detection of gene-environment interaction in cohort studies.

    Science.gov (United States)

    Coombes, Brandon; Basu, Saonli; McGue, Matt

    2017-07-01

    Identifying gene-environment (G-E) interactions can contribute to a better understanding of disease etiology, which may help researchers develop disease prevention strategies and interventions. One big criticism of studying G-E interaction is the lack of power due to sample size. Studies often restrict the interaction search to the top few hundred hits from a genome-wide association study or focus on potential candidate genes. In this paper, we test interactions between a candidate gene and an environmental factor to improve power by analyzing multiple variants within a gene. We extend recently developed score statistic based genetic association testing approaches to the G-E interaction testing problem. We also propose tests for interaction using gene-based summary measures that pool variants together. Although it has recently been shown that these summary measures can be biased and may lead to inflated type I error, we show that under several realistic scenarios, we can still provide valid tests of interaction. These tests use significantly less degrees of freedom and thus can have much higher power to detect interaction. Additionally, we demonstrate that the iSeq-aSum-min test, which combines a gene-based summary measure test, iSeq-aSum-G, and an interaction-based summary measure test, iSeq-aSum-I, provides a powerful alternative to test G-E interaction. We demonstrate the performance of these approaches using simulation studies and illustrate their performance to study interaction between the SNPs in several candidate genes and family climate environment on alcohol consumption using the Minnesota Center for Twin and Family Research dataset. © 2017 WILEY PERIODICALS, INC.

  3. Effects of Strength of Accent on an L2 Interactive Lecture Listening Comprehension Test

    Science.gov (United States)

    Ockey, Gary J.; Papageorgiou, Spiros; French, Robert

    2016-01-01

    This article reports on a study which aimed to determine the effect of strength of accent on listening comprehension of interactive lectures. Test takers (N = 21,726) listened to an interactive lecture given by one of nine speakers and responded to six comprehension items. The test taker responses were analyzed with the Rasch computer program…

  4. An interactive style of the testing database production for EIS

    Directory of Open Access Journals (Sweden)

    Milan Mišovič

    2006-01-01

    Full Text Available Using a progressive Information Technology for development of Software Modules for Enterprise Information Systems brings a lot of practical and theoretical problems. One of them is a verification of results achieved in Life Cycle Stages, especially in the analysis stage. Instead of a very deep theoretical approach we can use quite practical testing by means of a testing database. Such testing database has to be constructed gradually from the Data Flow Diagram by a special algorithm.This article introduces a formal description of the entity population and entity states. There is suggested to deal with fragments of the DFD that are produced with respect to the event set. This DFD event fragment is refined to transactions and their elementary functions. There is defined a transaction path in every transaction. By means of a special state equation system is generally defined conception of a correct functional processing of entities going along a selected transaction path. Solutions of such state equation systems are platform for getting a testing database.

  5. Testing theory of binary evolution with interacting binary stars

    Science.gov (United States)

    Ergma, E.; Sarna, M. J.

    2002-01-01

    Of particular interest to us is the study of mass loss and its influence on the evolution of a binary systems. For this we use theoretical evolutionary models, which include: mass accretion, mass loss, novae explosion, super--efficient wind, and mixing processes. To test our theoretical prediction we proposed to determine the 12C / 13C ratio via measurements of the 12CO and 13CO bands around 2.3 micron. The available observations (Exter at al. 2001, in preparation) show good agreement with the theoretical predictions (Sarna 1992), for Algol-type binaries. Our preliminary estimates of the isotopic ratios for pre-CV's and CV's (Catalan et al. 2000, Dhillon et al. 2001) agree with the theoretical predictions from the common--envelope binary evolution models by Sarna et al. (1995). For the SXT we proposed (Ergma & Sarna 2001) similar observational test, which has not been done yet.

  6. Remote Control and Testing of the Interactive TV-Decoder

    Directory of Open Access Journals (Sweden)

    K. Vlcek

    1995-12-01

    Full Text Available The article deals with assembling and application of a complex sequential circuit VHDL (VHSIC (Very High-Speed Integrated Circuit Hardware Description Language model. The circuit model is a core of a cryptographic device for the signal encoding and decoding of discreet transmissions by TV-cable net. The cryptographic algorithm is changable according to the user's wishes. The principles of creation and example implementations are presented in the article. The behavioural model is used to minimize mistakes in the ASICs (Application Specific Integrated Circuits. The circuit implementation uses the FPGA (Field Programmable Gate Array technology. The diagnostics of the circuit is based on remote testing by the IEEE Std 1149.1-1990. The VHDL model of diagnostic subsystem is created as an orthogonal model in relation to the cryptographic circuit VHDL model.

  7. Review of time-dependent fatigue behavior and life prediction for 2 1/4 Cr-1 Mo steel

    International Nuclear Information System (INIS)

    Booker, M.K.; Majumdar, S.

    1982-01-01

    Available data on creep-fatigue life and fracture behavior of 2 1/4 Cr-1 Mo steel are reviewed. Whereas creep-fatigue interaction is important for Type 304 stainless steel, oxidation effects appear to dominate the time-dependent fatigue behavior of 2 1/4 Cr-1 Mo steel. Four of the currently available predictive methods - the Linear Damage Rule, Frequency Separation Equation, Strain Range Partitioning Equation, and Damage Rate Equation - are evaluated for their predictive capability. Variations in the parameters for the various predictive methods with temperature, heat of material, heat treatment, and environment are investigated. Relative trends in the lives predicted by the various methods as functions of test duration, waveshape, etc., are discussed. The predictive methods will need modification in order to account for oxidation and aging effects in the 2 1/4 Cr-1 Mo steel. Future tests that will emphasize the difference between the various predictive methods are proposed

  8. Large scale sodium interactions. Part 2. Preliminary test results for limestone concrete

    International Nuclear Information System (INIS)

    Smaardyk, J.E.; Sutherland, H.J.; King, D.L.; Dahlgren, D.A.

    1977-01-01

    Any sodium cooled reactor system must consider the interaction of hot sodium with cell liners, and given either a failed liner or a hypothetical core disruptive accident, the interaction of hot sodium with concrete. The data base available for safety assessments involving these interactions is limited, especially for the concrete and failed liner interactions. To better understand what happens when hot sodium comes in contact with concrete, a series of tests is being carried out to investigate sodium-concrete reactions under conditions which are similar to actual reactor accident conditions. Tests cover the cases of sodium spills on bare concrete and on cells with defective steel liners. Specific objectives have been to obtain a complete description of the sodium/concrete interaction including heat balance, gas evolution and flow, movement and heat generation of the reaction zone, reaction product formation, and the layering or movement of the products

  9. Experimental strength evaluation of cylinders with a flat head subjected to internal pressure at elevated temperature

    International Nuclear Information System (INIS)

    Suzuki, Mitsuru; Makino, Yutaka

    1978-01-01

    The experiments using component test models such as a cylinder with a flat head and F.E.M. elastic analyses to investigate the secondary stress, peak stress and creep-fatigue interaction effect are described. The comparison of uniaxial stress with multiaxial stress about deformation and strength at elevated temperatures are also described here. The results of experiments and analysis are summarized as follows: (1) The maximum stress as the equivalent stress is the most suitable for the prediction of the creep failure life of cylinders subjected to internal pressure using the uniaxial creep test results. And the Mises's equivalent stress is the suitable for this prediction using the data of the onset of the uniaxial tertiary creep. (2) In the creep characteristics of the cylinder there, is no tertiary creep stage, and the rupture elongation of the cylinder accords with the elongation of the onset of the uniaxial tertiary creep. (3) It was recognized that the secondary stress occurred at the corner of the cylinder with a flat head has a little effect on creep and creep-fatigue life. (4) The life reduction effect due to the creep-fatigue interaction around the corner was recognized by the linear damage rule and compared with the value of Code Case 1592. (5) A difference of failure modes by imposed conditions for vessel with the size-discontinuity section was recognized by the cyclic internal pressure tests with hold time. (author)

  10. Efficient two-step testing of gene-gene interactions in genome-wide association studies.

    Science.gov (United States)

    Lewinger, Juan Pablo; Morrison, John L; Thomas, Duncan C; Murcray, Cassandra E; Conti, David V; Li, Dalin; Gauderman, W James

    2013-07-01

    Exhaustive testing of all possible SNP pairs in a genome-wide association study (GWAS) generally yields low power to detect gene-gene (G × G) interactions because of small effect sizes and stringent requirements for multiple-testing correction. We introduce a new two-step procedure for testing G × G interactions in case-control GWAS to detect interacting single nucleotide polymorphisms (SNPs) regardless of their marginal effects. In an initial screening step, all SNP pairs are tested for gene-gene association in the combined sample of cases and controls. In the second step, the pairs that pass the screening are followed up with a traditional test for G × G interaction. We show that the two-step method is substantially more powerful to detect G × G interactions than the exhaustive testing approach. For example, with 2,000 cases and 2,000 controls, the two-step method can have more than 90% power to detect an interaction odds ratio of 2.0 compared to less than 50% power for the exhaustive testing approach. Moreover, we show that a hybrid two-step approach that combines our newly proposed two-step test and the two-step test that screens for marginal effects retains the best power properties of both. The two-step procedures we introduce have the potential to uncover genetic signals that have not been previously identified in an initial single-SNP GWAS. We demonstrate the computational feasibility of the two-step G × G procedure by performing a G × G scan in the asthma GWAS of the University of Southern California Children's Health Study. © 2013 WILEY PERIODICALS, INC.

  11. Testing GxG interactions between coinfecting microbial parasite genotypes within hosts

    Directory of Open Access Journals (Sweden)

    Rebecca D Schulte

    2014-05-01

    Full Text Available Host-parasite interactions represent one of the strongest selection pressures in nature. They are often governed by genotype-specific (GxG interactions resulting in host genotypes that differ in resistance and parasite genotypes that differ in virulence depending on the antagonist’s genotype. Another type of GxG interactions, which is often neglected but which certainly influences host-parasite interactions, are those between coinfecting parasite genotypes. Mechanistically, within-host parasite interactions may range from competition for limited host resources to cooperation for more efficient host exploitation. The exact type of interaction, i.e. whether competitive or cooperative, is known to affect life-history traits such as virulence. However, the latter has been shown for chosen genotype combinations only, not considering whether the specific genotype combination per se may influence the interaction (i.e. GxG interactions. Here, we want to test for the presence of GxG interactions between coinfections of the bacterium Bacillus thuringiensis infecting the nematode Caenorhabditis elegans by combining two non-pathogenic and five pathogenic strains in all possible ways. Furthermore, we evaluate whether the type of interaction, reflected by the direction of virulence change of multiple compared to single infections, is genotype-specific. Generally, we found no indication for GxG interactions between non-pathogenic and pathogenic bacterial strains, indicating that virulence of pathogenic strains is equally affected by both non-pathogenic strains. Specific genotype combinations, however, differ in the strength of virulence change, indicating that the interaction type between coinfecting parasite strains and thus the virulence mechanism is specific for different genotype combinations. Such interactions are expected to influence host-parasite interactions and to have strong implications for coevolution.

  12. Melt water interaction tests. PREMIX tests PM10 and PM11

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, A.; Schuetz, W.; Will, H. [Forschungszentrum Karlsruhe Inst. fuer Reaktorsicherheit, Karlsruhe (Germany)

    1998-01-01

    A series of experiments is being performed in the PREMIX test facility in which the mixing behaviour is investigated of a hot alumina melt discharged into water. The major parameters have been: the melt mass, the number of nozzles, the distance between the nozzle and the water, and the depth of the water. The paper describes the last two tests in which 20 kg of melt were released through one and three nozzles, respectively, directly into the water whose depth was 500 mm. The melt penetration and the associated phenomena of mixing are described by means of high-speed films and various measurements. The steam production and, subsequently, the pressure increased markedly only after the melt had reached the bottom of the pool. Spreading of the melt across the bottom caused violent boiling in both tests. Whereas the boiling lasted for minutes in the single-jet test, a steam explosion occurred in the triple-jet test about one second after the start of melt penetration. (author)

  13. INTERACT

    DEFF Research Database (Denmark)

    Jochum, Elizabeth; Borggreen, Gunhild; Murphey, TD

    This paper considers the impact of visual art and performance on robotics and human-computer interaction and outlines a research project that combines puppetry and live performance with robotics. Kinesics—communication through movement—is the foundation of many theatre and performance traditions...... including puppetry and dance. However, the aesthetics of these traditions vary across cultures and carry different associative and interpretive meanings. Puppetry offers a useful frame for understanding the relationship between abstract and imitative gestures and behavior, and instantiates the complex...... interaction between a human operator and an artificial actor or agent. We can apply insights from puppetry to develop culturally-aware robots. Here we describe the development of a robotic marionette theatre wherein robotic controllers assume the role of human puppeteers. The system has been built, tested...

  14. The effects of angelica essential oil in social interaction and hole-board tests.

    Science.gov (United States)

    Min, Li; Chen, Si Wei; Li, Wei Jing; Wang, Rui; Li, Yu Lei; Wang, Wen Juan; Mi, Xiao Juan

    2005-08-01

    In our previous studies, we have demonstrated the anxiolytic effects of angelica essential oil in three anxiety models using mice. This study aimed to characterize the similar behavior effects of angelica essential oil in the social interaction test of anxiety and the hole-board test of exploration and locomotor activity in rats. These results indicate that angelica essential oil possessed a wide range of anxiolytic properties. In the social interaction test, angelica essential oil decreased aggressive behaviors at the doses of 21 and 42 mg/kg, while the doses of 21 and 42 mg/kg significantly increased social interaction time of the high light, unfamiliar test condition and 21 mg/kg could also prolong social interaction time of the high light, familiar test condition. In the hole-board test, angelica essential oil at 10.5 mg/kg significantly increased head-dipping counts and duration. Thus, our findings suggest the potential usefulness of angelica essential oil against various types of anxiety-related disorders and social failure.

  15. Usability Testing for Developing Effective Interactive Multimedia Software: Concepts, Dimensions, and Procedures

    Directory of Open Access Journals (Sweden)

    Sung Heum Lee

    1999-04-01

    Full Text Available Usability testing is a dynamic process that can be used throughout the process of developing interactive multimedia software. The purpose of usability testing is to find problems and make recommendations to improve the utility of a product during its design and development. For developing effective interactive multimedia software, dimensions of usability testing were classified into the general categories of: learnability; performance effectiveness; flexibility; error tolerance and system integrity; and user satisfaction. In the process of usability testing, evaluation experts consider the nature of users and tasks, tradeoffs supported by the iterative design paradigm, and real world constraints to effectively evaluate and improve interactive multimedia software. Different methods address different purposes and involve a combination of user and usability testing, however, usability practitioners follow the seven general procedures of usability testing for effective multimedia development. As the knowledge about usability testing grows, evaluation experts will be able to choose more effective and efficient methods and techniques that are appropriate to their goals.

  16. Testing the Effectiveness of Interactive Multimedia for Library-User Education

    Science.gov (United States)

    Markey, Karen; Armstrong, Annie; De Groote, Sandy; Fosmire, Michael; Fuderer, Laura; Garrett, Kelly; Georgas, Helen; Sharp, Linda; Smith, Cheri; Spaly, Michael; Warner, Joni E.

    2005-01-01

    A test of the effectiveness of interactive multimedia Web sites demonstrates that library users' topic knowledge was significantly greater after visiting the sites than before. Library users want more such sites about library services, their majors, and campus life generally. Librarians describe the roles they want to play on multimedia production…

  17. The Interactive Seminar: An Educational Approach for Voluntary HIV Testing in a Drug Dependence Treatment Unit.

    Science.gov (United States)

    Sedhom, Laila; And Others

    1994-01-01

    A survey of 118 male patients in a drug dependence treatment unit before and after an interactive seminar with a nonjudgmental professional showed that seminar participants, especially intravenous drug users, had higher rates of voluntary HIV testing than nonparticipants. Drug users who completed detoxification and attended the seminar also had…

  18. Dispersion Interactions between Rare Gas Atoms: Testing the London Equation Using ab Initio Methods

    Science.gov (United States)

    Halpern, Arthur M.

    2011-01-01

    A computational chemistry experiment is described in which students can use advanced ab initio quantum mechanical methods to test the ability of the London equation to account quantitatively for the attractive (dispersion) interactions between rare gas atoms. Using readily available electronic structure applications, students can calculate the…

  19. Interactions among Domain-Specific Expectancies, Values, and Gender: Predictors of Test Anxiety during Early Adolescence

    Science.gov (United States)

    Selkirk, Laura C.; Bouchey, Heather A.; Eccles, Jacquelynne S.

    2011-01-01

    This research focuses on the interaction between students' domain-specific expectancies and values as a predictor of test anxiety. A subsample of adolescents from the MSALT dataset are used in the current study; students complete measures during the spring of sixth grade and again during the spring of seventh grade. Overall, findings provide…

  20. Evaluation of Two Methods for Modeling Measurement Errors When Testing Interaction Effects with Observed Composite Scores

    Science.gov (United States)

    Hsiao, Yu-Yu; Kwok, Oi-Man; Lai, Mark H. C.

    2018-01-01

    Path models with observed composites based on multiple items (e.g., mean or sum score of the items) are commonly used to test interaction effects. Under this practice, researchers generally assume that the observed composites are measured without errors. In this study, we reviewed and evaluated two alternative methods within the structural…

  1. A comparison of usability methods for testing interactive health technologies: Methodological aspects and empirical evidence

    NARCIS (Netherlands)

    Jaspers, Monique W. M.

    2009-01-01

    OBJECTIVE: Usability evaluation is now widely recognized as critical to the success of interactive health care applications. However, the broad range of usability inspection and testing methods available may make it difficult to decide on a usability assessment plan. To guide novices in the

  2. Design related aspects in advanced nuclear fission plants

    International Nuclear Information System (INIS)

    Hoffelner, Wolfgang

    2011-01-01

    Important issues to be considered for design of future reactors are: extrapolation of stress rupture data, creep-fatigue, negligible creep, damage monitoring. The paper highlights some new developments taking examples from a martensitic steel (mod 9% Cr), oxide dispersion strengthened (ODS) steels and nickel-base superalloys. Traditional approaches to extrapolation of (thermal) stress rupture data like Larson-Miller Parameter or Monkman-Grant rule seem to be valid concepts also for advanced reactors. However, a significant influence of cyclic softening on creep rates and stress rupture data can be expected as shown for grade 91. This is particularly true for creep-fatigue interactions. Based on cyclic stress-strain behaviour it is also possible to get very good life-time predictions under creep-fatigue with a strain range separation (inelastic fatigue and creep ranges) technique which could replace the currently used linear life fraction rule. Results from in-beam irradiation creep reveal no significant influence of dispersoid size. It can be assumed that irradiation creep is a matrix property. Finally it is shown that micro-sample testing of exposed material could be used as an advanced method for damage assessment in future nuclear power plants.

  3. The Influence of Dwell Time on Low Cycle Fatigue Behavior of Ni-base Superalloy IC10

    Science.gov (United States)

    Wang, Anqiang; Liu, Lu; Wen, Zhixun; Li, Zhenwei; Yue, Zhufeng

    2017-09-01

    Low cycle fatigue and creep-fatigue experiments of IC10 Ni-base superalloy plate specimens with multiple holes were performed below 1,000 °C. The average fatigue life is 105.4 cycles, while the creep-fatigue life is 103.4 cycles, which shows that the life of creep-fatigue is reduced 1-2 times compared with low cycle fatigue life. After tests, the detailed fracture and microscopic structure evolution were observed by scanning electron microscopy (SEM); meanwhile, the constitutive model based on crystal plasticity theory was established and the fracture mechanism was analyzed. Three conclusions have been obtained: First, the load during dwell time leads to the damage accumulation caused by deformation and the interaction of fatigue and creep shortens the service life of materials seriously. Second, in order to maintain the macroscopic deformation, a new slip plane starts to makes the dislocation slide in reverse direction, which leads to fatigue damage and initial cracks. Third, the inner free surface creates opportunities for escape of the dislocation line, which is caused by the cavity. What's more, the cure dislocation generated by cyclic loading contributes to the formation and growth of cavities.

  4. Testing advanced driver assistance systems with the interactive driving simulator; Erprobung von Fahrerassistenzsystemen mit dem Interactive Driving Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Friedrichs, A.; Grosse-Kappenberg, S.; Happe, J. [Zentrum fuer Lern- und Wissensmanagement und Lehrstuhl Informatik im Maschinenbau ZLW/IMA der RWTH Aachen (Germany)

    2005-07-01

    The Centre for Learning and Knowledge Management and Department of Computer Science in Engineering of the Technical University Aachen has developed a truck driving simulator which combines a driving simulation as well as traffic flow calculations to the interactive Driving Simulator (InDriveS). In real-time the effects of the driver's behaviour on the surrounding traffic are considered and vice versa. The integrative part of InDriveS is a software-in-the-loop and hardware-in-the-loop development environment. By means of this tool, all phases of development (Analysis, Design, Modelling, Simulation, Implementation as well as Testing and Evaluation) of new vehicle technologies, e.g. Information and Assistance Systems, can be realised in consideration of the road traffic and the driver's behaviour. (orig.)

  5. Report on FY17 testing in support of integrated EPP-SMT design methods development

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanli . [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jetter, Robert I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sham, T. -L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    The goal of the proposed integrated Elastic Perfectly-Plastic (EPP) and Simplified Model Test (SMT) methodology is to incorporate a SMT data-based approach for creep-fatigue damage evaluation into the EPP methodology to avoid the separate evaluation of creep and fatigue damage and eliminate the requirement for stress classification in current methods; thus greatly simplifying evaluation of elevated temperature cyclic service. The purpose of this methodology is to minimize over-conservatism while properly accounting for localized defects and stress risers. To support the implementation of the proposed methodology and to verify the applicability of the code rules, thermomechanical tests continued in FY17. This report presents the recent test results for Type 1 SMT specimens on Alloy 617 with long hold times, pressurization SMT on Alloy 617, and two-bar thermal ratcheting test results on SS316H at the temperature range of 405 °C to 705 °C. Preliminary EPP strain range analysis on the two-bar tests are critically evaluated and compared with the experimental results.

  6. Oxide-metal corium-concrete interaction test in the Vulcano facility

    International Nuclear Information System (INIS)

    Journeau, Ch.; Piluso, P.; Haquet, J.F.; Saretta, S.; Boccaccio, E.; Bonnet, J.M.

    2007-01-01

    Corium is likely to melt through the vessel and interact with the reactor pit concrete. Corium is made of a UO 2 -rich oxidic part, in which most of the decay heat is dissipated, and of a metallic part, mainly molten steel. An experiment has been set up in the Vulcano facility in which oxidic and metallic mixtures are molten in separate furnaces and poured in a concrete cavity. Induction heating is provided to the pool upper part thanks to shielding coils, so that, in case of stratification, the lighter oxidic corium-concrete mixture receives most of the power. Pre-calculations with the TOLBIAC-ICB corium-concrete interaction code based on the phase segregation model have provided valuable information for the dimensioning of this test: a thick metallic layer (>10 kg or 4 cm) has been chosen in order to obtain significant cavity ablation profiles depending on the selected heat transfer and stratification models. Stratification of the two liquid phases is predicted to occur in less than 10 minutes. In September 2006, the experiment was performed in the Vulcano facility. The corium was made of about 15 kg of steel at 1700 C and 30 kg of oxides (70% UO 2 , 16 % ZrO 2 and 14% concrete load) above 2000 C. It was poured in a limestone-rich concrete. This concrete type was selected for the first test, since the ablation is isotropic except for the initial transient, during oxidic corium-concrete interaction tests. 32 kW of induction power have been provided to the pool during the 4-hour test. The destruction of in-concrete thermocouples indicates that ablation was first mainly radial then became isotropic. This is quite similar to the ablation progression observed during previous tests with oxidic corium interacting with this type of concrete. Important 'volcanic activity' has been observed at the corium pool surface, compared to the previous oxidic corium experiments at Vulcano. (authors)

  7. JPL control/structure interaction test bed real-time control computer architecture

    Science.gov (United States)

    Briggs, Hugh C.

    1989-01-01

    The Control/Structure Interaction Program is a technology development program for spacecraft that exhibit interactions between the control system and structural dynamics. The program objectives include development and verification of new design concepts - such as active structure - and new tools - such as combined structure and control optimization algorithm - and their verification in ground and possibly flight test. A focus mission spacecraft was designed based upon a space interferometer and is the basis for design of the ground test article. The ground test bed objectives include verification of the spacecraft design concepts, the active structure elements and certain design tools such as the new combined structures and controls optimization tool. In anticipation of CSI technology flight experiments, the test bed control electronics must emulate the computation capacity and control architectures of space qualifiable systems as well as the command and control networks that will be used to connect investigators with the flight experiment hardware. The Test Bed facility electronics were functionally partitioned into three units: a laboratory data acquisition system for structural parameter identification and performance verification; an experiment supervisory computer to oversee the experiment, monitor the environmental parameters and perform data logging; and a multilevel real-time control computing system. The design of the Test Bed electronics is presented along with hardware and software component descriptions. The system should break new ground in experimental control electronics and is of interest to anyone working in the verification of control concepts for large structures.

  8. Testing refined shell-model interactions in the sd shell: Coulomb excitation of Na26

    CERN Document Server

    Siebeck, B; Blazhev, A; Reiter, P; Altenkirch, R; Bauer, C; Butler, P A; De Witte, H; Elseviers, J; Gaffney, L P; Hess, H; Huyse, M; Kröll, T; Lutter, R; Pakarinen, J; Pietralla, N; Radeck, F; Scheck, M; Schneiders, D; Sotty, C; Van Duppen, P; Vermeulen, M; Voulot, D; Warr, N; Wenander, F

    2015-01-01

    Background: Shell-model calculations crucially depend on the residual interaction used to approximate the nucleon-nucleon interaction. Recent improvements to the empirical universal sd interaction (USD) describing nuclei within the sd shell yielded two new interactions—USDA and USDB—causing changes in the theoretical description of these nuclei. Purpose: Transition matrix elements between excited states provide an excellent probe to examine the underlying shell structure. These observables provide a stringent test for the newly derived interactions. The nucleus Na26 with 7 valence neutrons and 3 valence protons outside the doubly-magic 16O core is used as a test case. Method: A radioactive beam experiment with Na26 (T1/2=1,07s) was performed at the REX-ISOLDE facility (CERN) using Coulomb excitation at safe energies below the Coulomb barrier. Scattered particles were detected with an annular Si detector in coincidence with γ rays observed by the segmented MINIBALL array. Coulomb excitation cross sections...

  9. Results of thermal interaction tests for various materials performed in the Ispra tank facility

    International Nuclear Information System (INIS)

    Fasoli-Stella, P.; Holtbecker, H.; Jorzik, E.; Schlittenhardt, P.; Thoma, U.

    A test facility for fuel/coolant thermal interaction measurements is described together with recent improvements of the melting oven design, the instrumentation and the collection and cleaning of the debris. The formation of a UO 2 crust on the melting crucible is investigated theoretically taking into account the heat losses during transport of the crucible from the oven to the reaction chamber. Experimental results for the systems steel-sodium, steel-water and UO 2 -sodium are presented and discussed with respect to particle size distribution and appearence of the debris. A sodium/fuel interaction model is introduced in the hydrodynamic REXCO-H-code. The results of test calculations are dealt with

  10. ATTILA 2 S. A technical and interactive test language for architecture allowing simultaneity

    International Nuclear Information System (INIS)

    Batllo, M.

    1980-01-01

    The name ATTILA 2 S is inspired from ATLAS, test language adopted by the Department of Defence of America (D.O.D.) but cannot be implemented on our installation. ATTILA 2 S is principally characterized by: its technical vocabulary (P.O.L.), its interactivity, its simultaneity with main job (Multiprogramming and Multiprocessing allowed by multiprocessors architecture. This language has been developed for the Paris C.R.T. system (Photographies analysis system) on Control Data Cyber 72 computer [fr

  11. Testing hadronic interactions at ultrahigh energies with air showers measured by the Pierre Auger Observatory

    Czech Academy of Sciences Publication Activity Database

    Aab, A.; Abreu, P.; Aglietta, M.; Blažek, Jiří; Boháčová, Martina; Chudoba, Jiří; Ebr, Jan; Mandát, Dušan; Nečesal, Petr; Palatka, Miroslav; Pech, Miroslav; Prouza, Michael; Řídký, Jan; Schovánek, Petr; Trávníček, Petr; Vícha, Jakub

    2016-01-01

    Roč. 117, č. 19 (2016), 1-9, č. článku 192001. ISSN 0031-9007 R&D Projects: GA MŠk LM2015038; GA MŠk LG15014; GA ČR(CZ) GA14-17501S Institutional support: RVO:68378271 Keywords : Pierre Auger Observatory * test ing hadronic Interactions * ultrahigh energies * air showers Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 8.462, year: 2016

  12. Testing for constant nonparametric effects in general semiparametric regression models with interactions

    KAUST Repository

    Wei, Jiawei

    2011-07-01

    We consider the problem of testing for a constant nonparametric effect in a general semi-parametric regression model when there is the potential for interaction between the parametrically and nonparametrically modeled variables. The work was originally motivated by a unique testing problem in genetic epidemiology (Chatterjee, et al., 2006) that involved a typical generalized linear model but with an additional term reminiscent of the Tukey one-degree-of-freedom formulation, and their interest was in testing for main effects of the genetic variables, while gaining statistical power by allowing for a possible interaction between genes and the environment. Later work (Maity, et al., 2009) involved the possibility of modeling the environmental variable nonparametrically, but they focused on whether there was a parametric main effect for the genetic variables. In this paper, we consider the complementary problem, where the interest is in testing for the main effect of the nonparametrically modeled environmental variable. We derive a generalized likelihood ratio test for this hypothesis, show how to implement it, and provide evidence that our method can improve statistical power when compared to standard partially linear models with main effects only. We use the method for the primary purpose of analyzing data from a case-control study of colorectal adenoma.

  13. Orion Exploration Flight Test Reaction Control System Jet Interaction Heating Environment from Flight Data

    Science.gov (United States)

    White, Molly E.; Hyatt, Andrew J.

    2016-01-01

    The Orion Multi-Purpose Crew Vehicle (MPCV) Reaction Control System (RCS) is critical to guide the vehicle along the desired trajectory during re-­-entry. However, this system has a significant impact on the convective heating environment to the spacecraft. Heating augmentation from the jet interaction (JI) drives thermal protection system (TPS) material selection and thickness requirements for the spacecraft. This paper describes the heating environment from the RCS on the afterbody of the Orion MPCV during Orion's first flight test, Exploration Flight Test 1 (EFT-1). These jet plumes interact with the wake of the crew capsule and cause an increase in the convective heating environment. Not only is there widespread influence from the jet banks, there may also be very localized effects. The firing history during EFT-1 will be summarized to assess which jet bank interaction was measured during flight. Heating augmentation factors derived from the reconstructed flight data will be presented. Furthermore, flight instrumentation across the afterbody provides the highest spatial resolution of the region of influence of the individual jet banks of any spacecraft yet flown. This distribution of heating augmentation across the afterbody will be derived from the flight data. Additionally, trends with possible correlating parameters will be investigated to assist future designs and ground testing programs. Finally, the challenges of measuring JI, applying this data to future flights and lessons learned will be discussed.

  14. Accelerated life testing (ALT) in microelectronics and photonics: its role, attributes, challenges, pitfalls, and interaction with qualification tests

    Science.gov (United States)

    Suhir, Ephraim

    2002-06-01

    Accelerated life tests (ALTs) are aimed at the revealing and understanding the physics of the expected or occurred failures, i.e. are able to detect the possible failure modes and mechanisms. Another objective of the ALTs is to accumulate representative failure statistics. Adequately designed, carefully conducted, and properly interpreted ALTs provide a consistent basis for obtaining the ultimate information of the reliability of a product - the predicted probability of failure after the given time of service. Such tests can dramatically facilitate the solution to the cost effectiveness and time-to-market problems. ALTs should play an important role in the evaluation, prediction and assurance of the reliability of microelectronics and optoelectronics devices and systems. In the majority of cases, ALTs should be conducted in addition to the qualification tests, which are required by the existing standards. There might be also situations, when ALTs can be (and, probably, should be) used as an effective substitution for such standards, or, at least, as the basis for the improvement of the existing qualification specifications. We describe different types (categories) of accelerated tests, with an emphasis on the role that ALTs should play in the development, design, qualification and manufacturing of microelectronics and photonics products. We discuss the challenges associated with the implementation and use of the ALTs, potential pitfalls (primarily those associated with possible shifts in the mechanisms and modes of failure), and the interaction of the ALTs with other types of accelerated tests. The role of the nondestructive evaluations is also briefly outlined. The case of a laser welded optoelectronic package assembly is used to illustrate the concepts addressed.

  15. Toxicity tests based on predator-prey and competitive interactions between freshwater macroinvertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, E.J.; Blockwell, S.J.; Pascoe, D. [Univ. of Wales Coll. of Cardiff (United Kingdom)

    1994-12-31

    Simple multi-species toxicity tests based on the predation of Daphnia magna Straus by Hydra oligactis (Pallas) and competition between Gammarus pulex (L.) and Asellus aquaticus (L.) were used to determine the effects of three reference chemicals. Criteria examined included functional responses; time to first captures; handling times (predator/prey systems) and co-existence and growth. The tests which proved most practicable and sensitive (lowest observed effects 0.1, 21, and 80 {micro}g/l for lindane, copper and 3,4 dichloroaniline, respectively) were: (1) predator-prey tests: determining changes in the size-structure of predated D. magna populations and (2) competition tests: measuring the feeding rate of G. pulex competing with A. aquaticus, using a bioassay based on the time-response analysis of the consumption of Artemia salina eggs. The concentration of a chemical which affected particular response criteria was fond to depend on the test system employed. Results of the tests indicated that effects were often not dose-related and that a given criterion could be variously affected by different test concentrations. The complex pattern of responses may be explained in terms of the differential sensitivity of the interacting species and perhaps subtle alteration in strategies. The sensitivity of the bioassay endpoints is compared to those of a range of single species tests, and their value for predicting the impact pollutants may have upon natural freshwater ecosystems is discussed.

  16. Risk based lifetime assessment of piping under creep-fatigue conditions

    International Nuclear Information System (INIS)

    Bielak, O.; Bina, V.; Korous, J.

    2003-01-01

    The analysis of the steam pipeline lifetime is based on: (i) technical procedures supplied by Nuclear Electric R5; (ii) random interpretation of material damage accumulation laws for creep and fatigue; (iii) a stochastic model of the creep process (creep rupture strength, deformation characteristics); (iv) probabilistic description of geometrical quantities of the steam pipeline. The probabilistic procedure results in the calculation of the crack initiation risks both for the critical localities and for the steam pipeline as a whole (its subsystems, if need be). The residual lifetime was calculated from the conditional (a posteriori) probabilities. The risks of crack initiation was calculated for different operating periods (inspection frequency), and the periods were optimised to meet (i) the minimum risk of crack initiation and (2) the operation and economy criteria. The method also involves calculation of the residual lifetime from the updated data (material properties, dimensions). In the standard service-life calculations there is no difference between the weld and BM, the justification being that the weld is exposed to axial stress caused by internal pressure, which is one half of the hoop stress. Thus, the low creep resistant properties of the weld were ignored, as well as the uneven state of stress and its redistribution. In a number of cases it is the welds that are a weak point and therefore should receive considerable attention. The probabilistic method of lifetime and reliability assessment was verified on over 29 piping systems in power and petrochemical plants

  17. Implementation of creep-fatigue model into finite-element code to assess cooled turbine blade.

    CSIR Research Space (South Africa)

    Dedekind, MO

    1994-01-01

    Full Text Available Turbine blades which are designed with airfoil cooling are subject to thermo-mechanical fatigue as well as creep damage. These problems arise due to thermal cycling and high operating temperatures in service. An implementation of fatigue and creep...

  18. Creep/fatigue damage prediction of fast reactor components using shakedown methods

    International Nuclear Information System (INIS)

    Buckthorpe, D.E.

    1997-01-01

    The present status of the shakedown method is reviewed, the application of the shakedown based principles to complex hardening and creep behaviour is described and justified and the prediction of damage against design criteria outlined. Comparisons are made with full inelastic analysis solutions where these are available and against damage assessments using elastic and inelastic design code methods. Current and future developments of the method are described including a summary of the advances made in the development of the post process ADAPT, which has enabled the method to be applied to complex geometry features and loading cases. The paper includes a review of applications of the method to typical Fast Reactor structural example cases within the primary and secondary circuits. For the primary circuit this includes structures such as the large diameter internal shells which are surrounded by hot sodium and subject to slow and rapid thermal transient loadings. One specific case is the damage assessment associated with thermal stratifications within sodium and the effects of moving sodium surfaces arising from reactor trip conditions. Other structures covered are geometric features within components such as the Above Core structure and Intermediate Heat Exchanger. For the secondary circuit the method has been applied to alternative and more complex forms of geometry namely thick section tubeplates of the Steam Generator and a typical secondary circuit piping run. Both of these applications are in an early stage of development but are expected to show significant advantages with respect to creep and fatigue damage estimation compared with existing code methods. The principle application of the method to design has so far been focused on Austenitic Stainless steel components however current work shows some significant benefits may be possible from the application of the method to structures made from Ferritic steels such as Modified 9Cr 1Mo. This aspect is briefly discussed as a potential application and future development of the method. 8 refs, 14 figs, 5 tabs

  19. Core-concrete interactions with overlying water pools. The WETCOR-1 test

    Energy Technology Data Exchange (ETDEWEB)

    Blose, R.E. [Ktech Corp., Albuquerque, NM (United States); Powers, D.A.; Copus, E.R.; Brockmann, J.E.; Simpson, R.B.; Lucero, D.A. [Sandia National Labs., Albuquerque, NM (United States)

    1993-11-01

    The WETCOR-1 test of simultaneous interactions of a high-temperature melt with water and a limestone/common-sand concrete is described. The test used a 34.1-kg melt of 76.8 w/o Al{sub 2}O{sub 3}, 16.9 w/o CaO, and 4.0 w/o SiO{sub 2} heated by induction using tungsten susceptors. Once quasi-steady attack on concrete by the melt was established, an attempt was made to quench the melt at 1850 K with 295 K water flowing at 57 liters per minute. Net power into the melt at the time of water addition was 0.61 {plus_minus} 0.19 W/cm{sup 3}. The test configuration used in the WETCOR-1 test was designed to delay melt freezing to the walls of the test fixture. This was done to test hypotheses concerning the inherent stability of crust formation when high-temperature melts are exposed to water. No instability in crust formation was observed. The flux of heat through the crust to the water pool maintained over the melt in the test was found to be 0.52 {plus_minus} 0.13 MW/m{sup 2}. Solidified crusts were found to attenuate aerosol emissions during the melt concrete interactions by factors of 1.3 to 3.5. The combination of a solidified crust and a 30-cm deep subcooled water pool was found to attenuate aerosol emissions by factors of 3 to 15.

  20. Results of fission product release from intermediate-scale MCCI [molten core-concrete interaction] tests

    International Nuclear Information System (INIS)

    Spencer, B.W.; Thompson, D.H.; Fink, J.K.; Gunther, W.H.; Sehgal, B.R.

    1988-01-01

    A program of reactor-material molten core-concrete interaction (MCCI) tests and related analyses are under way at Argonne National Laboratory under sponsorship of the Electric Power Research Institute (EPRI). The particular objective of these tests is to provide data pertaining to the release of nonvolatile fission products such as La, Ba, and Sr, plus other aerosol materials, from the coupled thermal-hydraulic and chemical processes of the MCCI. The first stages of the program involving small and intermediate-scale tests have been completed. Three small-scale tests (/approximately/5 kg corium) and nine intermediate-scale tests (/approximately/30 kg corium) were performed between September 1985 and September 1987. Real reactor materials were used in these tests. Sustained internal heat generation at nominally 1 kW per kg of melt was provided by direct electrical heating of the corium mixture. MCCI tests were performed with both fully and partially oxidized corium mixtures that contained a variety of nonradioactive materials such as La 2 O 3 , BaO, and SrO to represent fission products. Both limestone/common sand and basaltic concrete basemats were used. The system was instrumented for characterization of the thermal hydraulic, chemical, gas release, and aerosol release processes

  1. Administration of neuropsychological tests using interactive voice response technology in the elderly: validation and limitations

    Directory of Open Access Journals (Sweden)

    Delyana Ivanova Miller

    2013-08-01

    Full Text Available Interactive voice response systems (IVR are computer programs, which interact with people to provide a number of services from business to health care. We examined the ability of an IVR system to administer and score a verbal fluency task (fruits and the digit span forward and backward in 158 community dwelling people aged between 65 and 92 years of age (full scale IQ of 68 to 134. Only 6 participants could not complete all tasks mostly due to early technical problems in the study. Participants were also administered the WAIS-IV and WMS-IV sub-tests. The IVR system correctly recognized 90% of the fruits in the verbal fluency task and 93-95% of the number sequences in the digit span. The IVR system typically underestimated the performance of participants because of voice recognition errors. In the digit span, these errors led to the erroneous discontinuation of the test: however the correlation between IVR scoring and clinical scoring was still high (93-95%. The correlation between the IVR verbal fluency and the WAIS-IV Similarities sub-test was 0.31. The correlation between the IVR digit span forward and backward and the in-person administration was 0.46. We discuss how valid and useful IVR systems are for neuropsychological testing in the elderly.

  2. Sequence Design for a Test Tube of Interacting Nucleic Acid Strands.

    Science.gov (United States)

    Wolfe, Brian R; Pierce, Niles A

    2015-10-16

    We describe an algorithm for designing the equilibrium base-pairing properties of a test tube of interacting nucleic acid strands. A target test tube is specified as a set of desired "on-target" complexes, each with a target secondary structure and target concentration, and a set of undesired "off-target" complexes, each with vanishing target concentration. Sequence design is performed by optimizing the test tube ensemble defect, corresponding to the concentration of incorrectly paired nucleotides at equilibrium evaluated over the ensemble of the test tube. To reduce the computational cost of accepting or rejecting mutations to a random initial sequence, the structural ensemble of each on-target complex is hierarchically decomposed into a tree of conditional subensembles, yielding a forest of decomposition trees. Candidate sequences are evaluated efficiently at the leaf level of the decomposition forest by estimating the test tube ensemble defect from conditional physical properties calculated over the leaf subensembles. As optimized subsequences are merged toward the root level of the forest, any emergent defects are eliminated via ensemble redecomposition and sequence reoptimization. After successfully merging subsequences to the root level, the exact test tube ensemble defect is calculated for the first time, explicitly checking for the effect of the previously neglected off-target complexes. Any off-target complexes that form at appreciable concentration are hierarchically decomposed, added to the decomposition forest, and actively destabilized during subsequent forest reoptimization. For target test tubes representative of design challenges in the molecular programming and synthetic biology communities, our test tube design algorithm typically succeeds in achieving a normalized test tube ensemble defect ≤1% at a design cost within an order of magnitude of the cost of test tube analysis.

  3. An Efficient Test for Gene-Environment Interaction in Generalized Linear Mixed Models with Family Data.

    Science.gov (United States)

    Mazo Lopera, Mauricio A; Coombes, Brandon J; de Andrade, Mariza

    2017-09-27

    Gene-environment (GE) interaction has important implications in the etiology of complex diseases that are caused by a combination of genetic factors and environment variables. Several authors have developed GE analysis in the context of independent subjects or longitudinal data using a gene-set. In this paper, we propose to analyze GE interaction for discrete and continuous phenotypes in family studies by incorporating the relatedness among the relatives for each family into a generalized linear mixed model (GLMM) and by using a gene-based variance component test. In addition, we deal with collinearity problems arising from linkage disequilibrium among single nucleotide polymorphisms (SNPs) by considering their coefficients as random effects under the null model estimation. We show that the best linear unbiased predictor (BLUP) of such random effects in the GLMM is equivalent to the ridge regression estimator. This equivalence provides a simple method to estimate the ridge penalty parameter in comparison to other computationally-demanding estimation approaches based on cross-validation schemes. We evaluated the proposed test using simulation studies and applied it to real data from the Baependi Heart Study consisting of 76 families. Using our approach, we identified an interaction between BMI and the Peroxisome Proliferator Activated Receptor Gamma ( PPARG ) gene associated with diabetes.

  4. An Efficient Test for Gene-Environment Interaction in Generalized Linear Mixed Models with Family Data

    Directory of Open Access Journals (Sweden)

    Mauricio A. Mazo Lopera

    2017-09-01

    Full Text Available Gene-environment (GE interaction has important implications in the etiology of complex diseases that are caused by a combination of genetic factors and environment variables. Several authors have developed GE analysis in the context of independent subjects or longitudinal data using a gene-set. In this paper, we propose to analyze GE interaction for discrete and continuous phenotypes in family studies by incorporating the relatedness among the relatives for each family into a generalized linear mixed model (GLMM and by using a gene-based variance component test. In addition, we deal with collinearity problems arising from linkage disequilibrium among single nucleotide polymorphisms (SNPs by considering their coefficients as random effects under the null model estimation. We show that the best linear unbiased predictor (BLUP of such random effects in the GLMM is equivalent to the ridge regression estimator. This equivalence provides a simple method to estimate the ridge penalty parameter in comparison to other computationally-demanding estimation approaches based on cross-validation schemes. We evaluated the proposed test using simulation studies and applied it to real data from the Baependi Heart Study consisting of 76 families. Using our approach, we identified an interaction between BMI and the Peroxisome Proliferator Activated Receptor Gamma (PPARG gene associated with diabetes.

  5. Two-Sample Tests for High-Dimensional Linear Regression with an Application to Detecting Interactions.

    Science.gov (United States)

    Xia, Yin; Cai, Tianxi; Cai, T Tony

    2018-01-01

    Motivated by applications in genomics, we consider in this paper global and multiple testing for the comparisons of two high-dimensional linear regression models. A procedure for testing the equality of the two regression vectors globally is proposed and shown to be particularly powerful against sparse alternatives. We then introduce a multiple testing procedure for identifying unequal coordinates while controlling the false discovery rate and false discovery proportion. Theoretical justifications are provided to guarantee the validity of the proposed tests and optimality results are established under sparsity assumptions on the regression coefficients. The proposed testing procedures are easy to implement. Numerical properties of the procedures are investigated through simulation and data analysis. The results show that the proposed tests maintain the desired error rates under the null and have good power under the alternative at moderate sample sizes. The procedures are applied to the Framingham Offspring study to investigate the interactions between smoking and cardiovascular related genetic mutations important for an inflammation marker.

  6. Jet-Surface Interaction: High Aspect Ratio Nozzle Test, Nozzle Design and Preliminary Data

    Science.gov (United States)

    Brown, Clifford; Dippold, Vance

    2015-01-01

    The Jet-Surface Interaction High Aspect Ratio (JSI-HAR) nozzle test is part of an ongoing effort to measure and predict the noise created when an aircraft engine exhausts close to an airframe surface. The JSI-HAR test is focused on parameters derived from the Turbo-electric Distributed Propulsion (TeDP) concept aircraft which include a high-aspect ratio mailslot exhaust nozzle, internal septa, and an aft deck. The size and mass flow rate limits of the test rig also limited the test nozzle to a 16:1 aspect ratio, half the approximately 32:1 on the TeDP concept. Also, unlike the aircraft, the test nozzle must transition from a single round duct on the High Flow Jet Exit Rig, located in the AeroAcoustic Propulsion Laboratory at the NASA Glenn Research Center, to the rectangular shape at the nozzle exit. A parametric nozzle design method was developed to design three low noise round-to-rectangular transitions, with 8:1, 12:1, and 16: aspect ratios, that minimizes flow separations and shocks while providing a flat flow profile at the nozzle exit. These designs validated using the WIND-US CFD code. A preliminary analysis of the test data shows that the actual flow profile is close to that predicted and that the noise results appear consistent with data from previous, smaller scale, tests. The JSI-HAR test is ongoing through October 2015. The results shown in the presentation are intended to provide an overview of the test and a first look at the preliminary results.

  7. Synergistic effect of the interaction between curcumin and diclofenac on the formalin test in rats.

    Science.gov (United States)

    De Paz-Campos, Marco A; Ortiz, Mario I; Chávez Piña, Aracely E; Zazueta-Beltrán, Liliana; Castañeda-Hernández, Gilberto

    2014-10-15

    The association of non-steroidal anti-inflammatory drugs with certain plant extracts can increase antinociceptive activity, permitting the use of lower doses and thus limiting side effects. Therefore, the aim objective of the current study was to examine the effects of curcumin on the nociception and pharmacokinetics of diclofenac in rats. Antinociception was assessed using the formalin test. Diluted formalin was injected subcutaneously into the dorsal surface of the right hind paw. Nociceptive behavior was quantified as the number of flinches of the injected paw during 60 min after injection, and a reduction in formalin-induced flinching was interpreted as an antinociceptive response. Rats were treated with oral diclofenac (1-31 mg/kg), curcumin (3.1-100 mg/kg) or the diclofenac-curcumin combination (2.4-38.4 mg/kg). To determine the possibility of a pharmacokinetic interaction, the oral bioavailability of diclofenac (10 mg/kg) was studied in presence and the absence of curcumin (31 mg/kg). Diclofenac, curcumin, or diclofenac-curcumin combination produced an antinociceptive effect on the formalin test. ED30 values were estimated for the individual drugs, and an isobologram was constructed. The derived theoretical ED30 for the antinociceptive effect (19.2 mg/kg) was significantly different from the observed experimental ED30 value (9.8 mg/kg); hence, the interaction between diclofenac and curcumin that mediates the antinociceptive effect was synergistic. Notwithstanding, the interaction does not appear to involve pharmacokinetic mechanisms, as oral curcumin failed to produce any significant alteration in oral diclofenac bioavailability. Data suggest that the diclofenac-curcumin combination can interact at the systemic level and may have therapeutic advantages for the clinical treatment of inflammatory pain. Copyright © 2014 Elsevier GmbH. All rights reserved.

  8. Target Properties Effects on Central versus Peripheral Vertical Fusion Interaction Tested on a 3D Platform.

    Science.gov (United States)

    Zhang, Di; Neveu, Pascaline; Fattakhova, Yulia; Ferragut, Stéphanie; Lamard, Mathieu; Cochener, Béatrice; de Bougrenet de la Tocnaye, Jean-Louis

    2017-03-01

    We investigated the impact of target properties on vertical fusion amplitude (VFA) using a 3D display platform; the performance of the subjects allowed us to assess how central and peripheral retina regions interact during the fusion process. Fourteen subjects were involved in the test. VFA was recorded by varying the viewing distance, target complexity, disparity velocity, lighting condition and background luminance. Base-up prisms were introduced to create vertical disparity in the peripheral retinal area, whereas an offset compensation was added in the central area. Data were analyzed in JMP software using T-test and repeated-measures ANOVA tests. VFA is significantly affected by target properties including viewing distance, target complexity and disparity velocity; the impact from lighting condition and background luminance is not significant. Although central retina plays a crucial role in the fusion process, peripheral regions also affect the fusion performance when stimulus size on retina and contents disparity values are modified between central and peripheral vision. Vertical fusion is affected by various target properties. For the first time, peripheral vertical disparity direction effects on central fusion and eye motion response have been explored. Besides, a quantitative interaction of central and peripheral fusion is observed, which could be applied in clinical measurement on binocular disease concerning central and peripheral vision conflict.

  9. Tablet-Based Functional MRI of the Trail Making Test: Effect of Tablet Interaction Mode

    Directory of Open Access Journals (Sweden)

    Mahta Karimpoor

    2017-10-01

    Full Text Available The Trail Making Test (TMT is widely used for assessing executive function, frontal lobe abilities, and visual motor skills. Part A of this pen-and-paper test (TMT-A involves linking numbers randomly distributed in space, in ascending order. Part B (TMT-B alternates between linking numbers and letters. TMT-B is more demanding than TMT-A, but the mental processing that supports the performance of this test remains incompletely understood. Functional MRI (fMRI may help to clarify the relationship between TMT performance and brain activity, but providing an environment that supports real-world pen-and-paper interactions during fMRI is challenging. Previously, an fMRI-compatible tablet system was developed for writing and drawing with two modes of interaction: the original cursor-based, proprioceptive approach, and a new mode involving augmented reality to provide visual feedback of hand position (VFHP for enhanced user interaction. This study characterizes the use of the tablet during fMRI of young healthy adults (n = 22, with half of the subjects performing TMT with VFHP and the other half performing TMT without VFHP. Activation maps for both TMT-A and TMT-B performance showed considerable overlap between the two tablet modes, and no statistically differences in brain activity were detected when contrasting TMT-B vs. TMT-A for the two tablet modes. Behavioral results also showed no statistically different interaction effects for TMT-B vs. TMT-A for the two tablet modes. Tablet-based TMT scores showed reasonable convergent validity with those obtained by administering the standard pen-and-paper TMT to the same subjects. Overall, the results suggest that despite the slightly different mechanisms involved for the two modes of tablet interaction, both are suitable for use in fMRI studies involving TMT performance. This study provides information for using tablet-based TMT methods appropriately in future fMRI studies involving patients and healthy

  10. A comparison of usability methods for testing interactive health technologies: methodological aspects and empirical evidence.

    Science.gov (United States)

    Jaspers, Monique W M

    2009-05-01

    Usability evaluation is now widely recognized as critical to the success of interactive health care applications. However, the broad range of usability inspection and testing methods available may make it difficult to decide on a usability assessment plan. To guide novices in the human-computer interaction field, we provide an overview of the methodological and empirical research available on the three usability inspection and testing methods most often used. We describe two 'expert-based' and one 'user-based' usability method: (1) the heuristic evaluation, (2) the cognitive walkthrough, and (3) the think aloud. All three usability evaluation methods are applied in laboratory settings. Heuristic evaluation is a relatively efficient usability evaluation method with a high benefit-cost ratio, but requires high skills and usability experience of the evaluators to produce reliable results. The cognitive walkthrough is a more structured approach than the heuristic evaluation with a stronger focus on the learnability of a computer application. Major drawbacks of the cognitive walkthrough are the required level of detail of task and user background descriptions for an adequate application of the latest version of the technique. The think aloud is a very direct method to gain deep insight in the problems end users encounter in interaction with a system but data analyses is extensive and requires a high level of expertise both in the cognitive ergonomics and in computer system application domain. Each of the three usability evaluation methods has shown its usefulness, has its own advantages and disadvantages; no single method has revealed any significant results indicating that it is singularly effective in all circumstances. A combination of different techniques that compliment one another should preferably be used as their collective application will be more powerful than applied in isolation. Innovative mobile and automated solutions to support end-user testing have

  11. Heavy quark mass effects and improved tests of the flavor independence of strong interactions

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, P.N. [Univ. of Oxford (United Kingdom); SLD Collaboration

    1998-08-01

    A review is given of latest results on tests of the flavor independence of strong interactions. Heavy quark mass effects are evident in the data and are now taken into account at next-to-leading order in QCD perturbation theory. The strong-coupling ratios {alpha}{sub s}{sup b}/{alpha}{sub s}{sup uds} and {alpha}{sub s}{sup c}/{alpha}{sub s}{sup uds} are found to be consistent with unity. Determinations of the b-quark mass m{sub b} (M{sub Z}) are discussed.

  12. Interferencias de medicamentos con pruebas de laboratorios Drug interactions with laboratory tests

    OpenAIRE

    Yurisnel Ortiz Sánchez; Maria M García Tase; Keila K Rosales Arias; Yoleinis Vázquez Belizó; Ever Fonseca Olivares

    2005-01-01

    El presente trabajo se realizó teniendo en cuenta la insuficiente bibliografía sobre las interacciones de las pruebas de laboratorio con los fármacos, con el propósito de actualizar este tema para el personal médico. Se realizó una extensa revisión bibliográfica con vistas a exponer estas interacciones con los parámetros más usuales en el laboratorio de análisis clínico.Taking into account the lack of literature about interactions of lab tests with drugs, the present paper was aimed at updati...

  13. Validation of a Wave-Body Interaction Model by Experimental Tests

    DEFF Research Database (Denmark)

    Ferri, Francesco; Kramer, Morten; Pecher, Arthur

    2013-01-01

    Within the wave energy field, numerical simulation has recently acquired a worldwide consent as being a useful tool, besides physical model testing. The main goal of this work is the validation of a numerical model by experimental results. The numerical model is based on a linear wave-body intera......-body interaction theory, applied for a point absorber wave energy converter. The results show that the ratio floater size/wave amplitude is a key parameter for the validity of the applied theory....

  14. INTERACTIVE SIMULATIONS FOR DEMOS, EXHIBITIONS AND AS A TESTING PLATFORM FOR DESIGNERS

    Directory of Open Access Journals (Sweden)

    FEIDYEU ILIESCU Christian

    2016-11-01

    Full Text Available An interactive simulation is made by combining 3D graphics with the capabilities offered by the simulator in order to obtain valuable results to the design process or for communicating with potential clients through promotion. We can significantly reduce production costs, test products in multiple new scenarios in a short timeframe or to reduce the usage time of dedicated simulation software by using Autodesk Inventor along with Blender 3D. Although the models’ fidelity decreases as they’re converted for use in simulations, it is enough for solving potential problems that arise during modelling as well as for implementing commercial presentations.

  15. Test of hadronic interaction models with the KASCADE-Grande muon data

    Directory of Open Access Journals (Sweden)

    Schieler H.

    2013-06-01

    Full Text Available KASCADE-Grande is an air-shower observatory devoted for the detection of cosmic rays with energies in the interval of 1014 – 1018 eV, where the Grande array is responsible for the higher energy range. The experiment comprises different detection systems which allow precise measurements of the charged, electron and muon numbers of extensive air-showers (EAS. These data is employed not only to reconstruct the properties of the primary cosmic-ray particle but also to test hadronic interaction models at high energies. In this contribution, predictions of the muon content of EAS from QGSJET II-2, SIBYLL 2.1 and EPOS 1.99 are confronted with the experimental measurements performed with the KASCADE-Grande experiment in order to test the validity of these hadronic models commonly used in EAS simulations.

  16. Eye and hand motor interactions with the Symbol Digit Modalities Test in early multiple sclerosis.

    Science.gov (United States)

    Nygaard, Gro O; de Rodez Benavent, Sigrid A; Harbo, Hanne F; Laeng, Bruno; Sowa, Piotr; Damangir, Soheil; Bernhard Nilsen, Kristian; Etholm, Lars; Tønnesen, Siren; Kerty, Emilia; Drolsum, Liv; Inge Landrø, Nils; Celius, Elisabeth G

    2015-11-01

    Eye and hand motor dysfunction may be present early in the disease course of relapsing-remitting multiple sclerosis (RRMS), and can affect the results on visual and written cognitive tests. We aimed to test for differences in saccadic initiation time (SI time) between RRMS patients and healthy controls, and whether SI time and hand motor speed interacted with the written version of the Symbol Digit Modalities Test (wSDMT). Patients with RRMS (N = 44, age 35.1 ± 7.3 years), time since diagnosis < 3 years and matched controls (N = 41, age 33.2 ± 6.8 years) were examined with ophthalmological, neurological and neuropsychological tests, as well as structural MRI (white matter lesion load (WMLL) and brainstem lesions), visual evoked potentials (VEP) and eye-tracker examinations of saccades. SI time was longer in RRMS than controls (p < 0.05). SI time was not related to the Paced Auditory Serial Addition Test (PASAT), WMLL or to the presence of brainstem lesions. 9 hole peg test (9HP) correlated significantly with WMLL (r = 0.58, p < 0.01). Both SI time and 9HP correlated negatively with the results of wSDMT (r = -0.32, p < 0.05, r = -0.47, p < 0.01), but none correlated with the results of PASAT. RRMS patients have an increased SI time compared to controls. Cognitive tests results, exemplified by the wSDMT, may be confounded by eye and hand motor function. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Testing odorant-receptor interaction theories in humans through discrimination of isotopomers

    Directory of Open Access Journals (Sweden)

    Mara Andrione

    2017-12-01

    Full Text Available Odour reception takes place on the olfactory receptor neuron membrane, where molecular receptors interact with volatile odorant molecules. This interaction is classically thought to rely on chemical and structural features of the odorant, e.g. size, shape, functional groups. However, this model does not allow formulating a correct prediction for the smell of an odorant, suggesting that other molecular properties may play a role in the odour transduction process. An alternative model of olfaction maintains that odorant receptors can probe not only the structural and chemical features, but also the molecular vibration spectrum of the odorants. This constitutes the so-called vibration model of olfaction. According to this model, two isotopomers of the same molecule, i.e. two forms of the same molecule, one unaltered and one in which one or more hydrogen atoms are substituted with deuterium – which are therefore structurally and chemically identical, but with different molecular vibration spectra – would interact differently with an olfactory receptor, producing different olfactory perceptions in the brain. Here, we report on a duo-trio discrimination experiment conducted on human subjects, testing isotopomer pairs that have recently been shown to be differentially encoded in the honeybee brain.

  18. Administration of neuropsychological tests using interactive voice response technology in the elderly: validation and limitations.

    Science.gov (United States)

    Miller, Delyana Ivanova; Talbot, Vincent; Gagnon, Michèle; Messier, Claude

    2013-01-01

    Interactive voice response (IVR) systems are computer programs, which interact with people to provide a number of services from business to health care. We examined the ability of an IVR system to administer and score a verbal fluency task (fruits) and the digit span forward and backward in 158 community dwelling people aged between 65 and 92 years of age (full scale IQ of 68-134). Only six participants could not complete all tasks mostly due to early technical problems in the study. Participants were also administered the Wechsler Intelligence Scale fourth edition (WAIS-IV) and Wechsler Memory Scale fourth edition subtests. The IVR system correctly recognized 90% of the fruits in the verbal fluency task and 93-95% of the number sequences in the digit span. The IVR system typically underestimated the performance of participants because of voice recognition errors. In the digit span, these errors led to the erroneous discontinuation of the test: however the correlation between IVR scoring and clinical scoring was still high (93-95%). The correlation between the IVR verbal fluency and the WAIS-IV Similarities subtest was 0.31. The correlation between the IVR digit span forward and backward and the in-person administration was 0.46. We discuss how valid and useful IVR systems are for neuropsychological testing in the elderly.

  19. Status Report on the Fabrication of Fuel Cladding Chemical Interaction Test Articles for ATR Irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Richard H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-28

    FeCrAl alloys are a promising new class of alloys for light water reactor (LWR) applications due to their superior oxidation and corrosion resistance in high temperature environments. The current R&D efforts have focused on the alloy composition and processing routes to generate nuclear grade FeCrAl alloys with optimized properties for enhanced accident tolerance while maintaining properties needed for normal operation conditions. Therefore, the composition and processing routes must be optimized to maintain the high temperature steam oxidation (typically achieved by increasing the Cr and Al content) while still exhibiting properties conducive to normal operation in a LWR (such as radiation tolerance where reducing Cr content is favorable). Within this balancing act is the addition of understanding the influence on composition and processing routes on the FeCrAl alloys for fuel-cladding chemical interactions (FCCI). Currently, limited knowledge exists on FCCI for the FeCrAl-UO2 clad-fuel system. To overcome the knowledge gaps on the FCCI for the FeCrAl-UO2 clad-fuel system a series of fueled irradiation tests have been developed for irradiation in the Advanced Test Reactor (ATR) housed at the Idaho National Laboratory (INL). The first series of tests has already been reported. These tests used miniaturized 17x17 PWR fuel geometry rodlets of second-generation FeCrAl alloys fueled with industrial Westinghouse UO2 fuel. These rodlets were encapsulated within a stainless steel housing.To provide high fidelity experiments and more robust testing, a new series of rodlets have been developed deemed the Accident Tolerant Fuel Experiment #1 Oak Ridge National Laboratory FCCI test (ATF-1 ORNL FCCI). The main driving factor, which is discussed in detail, was to provide a radiation environment where prototypical fuel-clad interface temperatures are met while still maintaining constant contact between industrial fuel and the candidate cladding alloys

  20. High Temperature Stress Analysis on 61-pin Test Assembly for Reactor Core Sub-channel Flow Test

    International Nuclear Information System (INIS)

    Lee, Dongwon; Kim, Hyungmo; Lee, Hyeongyeon

    2014-01-01

    In this study, a high temperature heat transfer and stress analysis of a 61-pin test fuel assembly scaled down from the full scale 217-pin sub-assembly was conducted. The reactor core subchannel flow characteristic test will be conducted to evaluate uncertainties in computer codes used for reactor core thermal hydraulic design. Stress analysis for a 61-pin fuel assembly scaled down from Prototype Generation IV Sodium-cooled Fast Reactor was conducted and structural integrity in terms of load controlled stress limits was conducted. In this study, The evaluations on load-controlled stress limits for a 61-pin test fuel assembly to be used for reactor core subchannel flow distribution tests were conducted assuming that the test assembly is installed in a Prototype Generation IV Sodium-cooled fast reactor core. The 61-pin test assembly has the geometric similarity on P/D and H/D with PGSFR and material of fuel assembly is austenitic stainless steel 316L. The stress analysis results showed that 4.05MPa under primary load occurred at mid part of the test assembly and it was shown that the value of 4.05Mpa was far smaller than the code allowable of 127MPa. , it was shown that the stress intensity due to due to primary load is very small. The stress analysis results under primary and secondary loads showed that maximum stress intensity of 84.08MPa occurred at upper flange tangent to outer casing and the value was well within the code allowable of 268.8MPa. Integrity evaluations based on strain limits and creep-fatigue damage are underway according to the elevated design codes

  1. The Role of Cohesive Particle Interactions on Solids Uniformity and Mobilization During Jet Mixing: Testing Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Gauglitz, Phillip A.; Wells, Beric E.; Bamberger, Judith A.; Fort, James A.; Chun, Jaehun; Jenks, Jeromy WJ

    2010-04-01

    Radioactive waste that is currently stored in large underground tanks at the Hanford Site will be staged in selected double-shell tanks (DSTs) and then transferred to the Waste Treatment and Immobilization Plant (WTP). Before being transferred, the waste will be mixed, sampled, and characterized to determine if the waste composition and meets the waste feed specifications. Washington River Protection Solutions is conducting a Tank Mixing and Sampling Demonstration Program to determine the mixing effectiveness of the current baseline mixing system that uses two jet mixer pumps and the adequacy of the planned sampling method. The overall purpose of the demonstration program is to mitigate the technical risk associated with the mixing and sampling systems meeting the feed certification requirements for transferring waste to the WTP.The purpose of this report is to analyze existing data and evaluate whether scaled mixing tests with cohesive simulants are needed to meet the overall objectives of the small-scale mixing demonstration program. This evaluation will focus on estimating the role of cohesive particle interactions on various physical phenomena that occur in parts of the mixing process. A specific focus of the evaluation will be on the uniformity of suspended solids in the mixed region. Based on the evaluation presented in this report and the absence of definitive studies, the recommendation is to conduct scaled mixing tests with cohesive particles and augment the initial testing with non-cohesive particles. In addition, planning for the quantitative tests would benefit from having test results from some scoping experiments that would provide results on the general behavior when cohesive inter-particle forces are important.

  2. Reliable Predictors of Reduced Redundancy Test Performance: The Interaction between Lexical Bonds and Test Takers' Depth and Breadth of Vocabulary Knowledge

    Science.gov (United States)

    Janebi Enayat, Mostafa; Babaii, Esmat

    2018-01-01

    The present study intended to investigate whether test takers' breadth and depth of vocabulary knowledge can contribute to their efficient use of lexical bonds while restoring damaged texts in reduced redundancy tests. Moreover, the moderating role of general language proficiency was investigated in this interaction. In so doing, Vocabulary Levels…

  3. Innovative testing of spatial ability: interactive responding and the use of complex stimuli material.

    Science.gov (United States)

    Jelínek, Martin; Květon, Petr; Vobořil, Dalibor

    2015-02-01

    Despite initial expectations, which have emerged with the advancement of computer technology over the last decade of the twentieth century, scientific literature does not contain many relevant references regarding the development and use of innovative items in psychological testing. Our study presents and evaluates two novel item types. One item type is derived from a standard schematic test item used for the assessment of the spatial perception aspect of spatial ability, enhanced by an interactive response module. The performance on this item type is correlated with the performance on its paper and pencil counterpart. The other innovative item type used complex stimuli in the form of a short video of a ride through a city presented in an on-route perspective, which is intended to measure navigation skills and the ability to keep oneself oriented in space. In this case, the scores were related to the capacity of visuo-spatial working memory and also to the overall score in the paper/pencil test of spatial ability. The second relationship was moderated by gender.

  4. Fluid Structure Interaction in a Cold Flow Test and Transient CFD Analysis of Out-of-Round Nozzles

    Science.gov (United States)

    Ruf, Joseph; Brown, Andrew; McDaniels, David; Wang, Ten-See

    2010-01-01

    This viewgraph presentation describes two nozzle fluid flow interactions. They include: 1) Cold flow nozzle tests with fluid-structure interaction at nozzle separated flow; and 2) CFD analysis for nozzle flow and side loads of nozzle extensions with various out-of-round cases.

  5. Precision Tests of the Electroweak Interaction using Trapped Atoms and Ions

    Energy Technology Data Exchange (ETDEWEB)

    Melconian, Daniel George [Texas A & M Univ., College Station, TX (United States)

    2017-06-21

    The objective of the proposed research is to study fundamental aspects of the electroweak interaction via precision measurements in beta decay to test our current understanding of fundamental particles and forces as contained in the so-called "Standard Model" of particle physics. By comparing elegant experiments to rigorous theoretical predictions, we will either confirm the Standard Model to a higher degree and rule out models which seek to extend it, or find evidence of new physics and help guide theorists in developing the New Standard Model. The use of ion and neutral atom traps at radioactive ion beam facilities has opened up a new vista in precision low-energy nuclear physics experiments. Traps provide an ideal source of decaying atoms: they can be extremely cold (~1 mK); they are compact (~1 mm^3); and perhaps most importantly, the daughter particles escape with negligible distortions to their momenta in a scattering-free, open environment. The project is taking advantage of these technologies and applying them to precision beta-decay studies at radioactive beam facilities. The program consists of two complementary efforts: 1) Ion traps are an extremely versatile tool for purifying, cooling and bunching low-energy beams of short-lived nuclei. A large-bore (210~mm) superconducting 7-Tesla solenoid is at the heart of a Penning trap system for which there is a dedicated beamline at T-REX, the upgraded radioactive beam facility at the Cyclotron Institute, Texas A&M University. In addition to providing a general-purpose decay station, the flagship program for this system is measuring the ft-values and beta-neutrino correlation parameters from isospin T=2 superallowed beta-delayed proton decays, complimenting and expanding the already strong program in fundamental interactions at the Institute. 2) A magneto-optical trap is being used at the TRIUMF Neutral Atom Trap facility to observe the (un)polarized angular distribution parameters of isotopes of potassium. We

  6. A web-portal for interactive data exploration, visualization, and hypothesis testing.

    Science.gov (United States)

    Bartsch, Hauke; Thompson, Wesley K; Jernigan, Terry L; Dale, Anders M

    2014-01-01

    Clinical research studies generate data that need to be shared and statistically analyzed by their participating institutions. The distributed nature of research and the different domains involved present major challenges to data sharing, exploration, and visualization. The Data Portal infrastructure was developed to support ongoing research in the areas of neurocognition, imaging, and genetics. Researchers benefit from the integration of data sources across domains, the explicit representation of knowledge from domain experts, and user interfaces providing convenient access to project specific data resources and algorithms. The system provides an interactive approach to statistical analysis, data mining, and hypothesis testing over the lifetime of a study and fulfills a mandate of public sharing by integrating data sharing into a system built for active data exploration. The web-based platform removes barriers for research and supports the ongoing exploration of data.

  7. TWIST- The TRIUMF weak interaction symmetry test the Michel parameters from {mu}{sup +} decay

    Energy Technology Data Exchange (ETDEWEB)

    Rodning, N.L.; Andersson, W.; Davydov, Y.; Depommier, P.; Doornbos, J.; Faszer, W.; Gagliardi, C.A.; Gaponenko, A.; Gill, D.R.; Green, P.W.; Gumplinger, P.; Hardy, J.C.; Hasinoff, M.; Helmer, R.; Henderson, R.; Kitching, P.; Koetke, D.D.; Korkmaz, E.; Khruchinsky, A.; Maas, D.; Macdonald, J.A.; MacDonald, R.; Manweiler, R.; Marshall, G.; Mathie, T.; Musser, J.R.; Nord, P.; Olin, A.; Openshaw, R.; Ottewell, D.; Porcelli, T.; Poutissou, J-M.; Poutissou, R.; Price, G.; Quraan, M.; Schaapman, J.; Selivanov, V.; Sheffer, G.; Shin, B.; Sobratee, F.; Soukup, J.; Stanislaus, T.D.S.; Stinson, G.; Tacik, R.; Torokhov, V.; Tribble, R.E.; Vasiliev, M.A.; Walter, H-C.; Wang, S-C.; Wright, D

    2001-04-01

    We propose to make the first high precision measurements of nearly the entire differential spectrum (in energy and angle) of positrons from the decay of polarized muons. The main goal of the experiment is the precise testing of the (V - A) structure of electroweak interactions in the framework of the SU(2){sub L} x U(1) model. Highly polarized 'surface' {mu}{sup +} from the TRIUMF M13 beamline will enter a large volume, high field superconducting magnet on axis and will stop in a thin target at its center. The e{sup +} from the muon decay will be precisely tracked in the magnetic field using small-cell planar drift chambers. This spectrometer has been simulated with GEANT and EGS4 and has been demonstrated to meet the precision requirements.

  8. Testing Lorentz Invariance with Neutrinos from Ultrahigh Energy Cosmic Ray Interactions

    Science.gov (United States)

    Scully, Sean T.; Stecker, Floyd W.

    2010-01-01

    We have previously shown that a very small amount of Lorentz invariance violation (UV), which suppresses photomeson interactions of ultrahigh energy cosmic rays (UHECRs) with cosmic background radiation (CBR) photons, can produce a spectrum of cosmic rays that is consistent with that currently observed by the Pierre Auger Observatory (PAO) and HiRes experiments. Here, we calculate the corresponding flux of high energy neutrinos generated by the propagation of UHECR protons through the CBR in the presence of UV. We find that UV produces a reduction in the flux of the highest energy neutrinos and a reduction in the energy of the peak of the neutrino energy flux spectrum, both depending on the strength of the UV. Thus, observations of the UHE neutrino spectrum provide a clear test for the existence and amount of UV at the highest energies. We further discuss the ability of current and future proposed detectors make such observations.

  9. Interactions

    DEFF Research Database (Denmark)

    The main theme of this anthology is the unique interaction between mathematics, physics and philosophy during the beginning of the 20th century. Seminal theories of modern physics and new fundamental mathematical structures were discovered or formed in this period. Significant physicists such as ......The main theme of this anthology is the unique interaction between mathematics, physics and philosophy during the beginning of the 20th century. Seminal theories of modern physics and new fundamental mathematical structures were discovered or formed in this period. Significant physicists...... such as Lorentz and Einstein as well as mathematicians such as Poincare, Minkowski, Hilbert and Weyl contributed to this development. They created the new physical theories and the mathematical disciplines that play such paramount roles in their mathematical formulations. These physicists and mathematicians were...... also key figures in the philosophical discussions of nature and science - from philosophical tendencies like logical empiricism via critical rationalism to various neo-Kantian trends....

  10. LCT-coil design: Mechanical interaction between composite winding and steel casing under various test conditions

    International Nuclear Information System (INIS)

    Dolensky, B.; Messemer, G.; Zehlein, H.; Erb, J.

    1981-01-01

    Finite element computations for the structural design of the large superconducting toroidal field coil contributed by EURATOM to the Large Coil Test Facility (LCTF) at ORNL, USA were performed at KfK, using the ASKA code. The layout of the coil must consider different types of requirements: firstly, an optimal D-shaped contour minimizing circumferential stress gradients under normal operation in the toroidal arrangement must be defined. Secondly, the three-dimensional real design effects due to the actual support conditions, manufacturing tolerances etc. must be mastered for different basic operational and failure load cases. And, thirdly, the design must stand a single coil qualification test in the TOSKA-facility at KfK, Karlsruhe, FRG, before it is plugged into the LCTF. The emphasis of the paper is three-pronged according to these requirements: i) the 3D magnetic body forces as well as the underlying magnetic fields as computed by the HEDO-code are described. ii) The mechanical interaction between casing and winding as given elsewhere in terms of high stress regions, gaps, slide movements and contact forces for various load cases representing the LCTF test conditions is illustrated here by a juxtaposition of the operational deformations and stresses within the LCTF and the TOSKA. iii) Particular effects like the restraint imposed by a corset-type reinforcement of the coil in the TOSKA test facility to limit the breathing deformation are parametrically studied. Moreover, the possibilities to derive scaling laws which make essential results transferable to larger coils by extracting a 1D mechanical response from the 3D finite element model is also demonstrated. (orig./GG)

  11. Behavioral interactions of simvastatin and fluoxetine in tests of anxiety and depression

    Directory of Open Access Journals (Sweden)

    Santos T

    2012-10-01

    Full Text Available Tainaê Santos,1 Monaliza Marizete Baungratz,1 Suellen Priscila Haskel,2 Daniela Delwing de Lima,3 Júlia Niehues da Cruz,4 Débora Delwing Dal Magro,5 José Geraldo Pereira da Cruz51Department of Medicine, 2Department of Physiotherapy, Regional University of Blumenau, Santa Catarina, Brazil; 3Department of Pharmacy, University of Joinville Region, Santa Catarina, Brazil; 4Department of Medicine, University of the Extreme South of Santa Catarina, Santa Catarina, Brazil; 5Department of Natural Sciences, Regional University of Blumenau, Santa Catarina, BrazilAbstract: Simvastatin inhibits 3-hydroxy-3-methylglutaryl CoA reductase, the rate-limiting enzyme in the cholesterol biosynthetic pathway, and is widely used to control plasma cholesterol levels and prevent cardiovascular disease. However, emerging evidence indicates that the beneficial effects of simvastatin extend to the central nervous system. The effects of simvastatin combined with fluoxetine provide an exciting and potential paradigm to decreased anxiety and depression. Thus, the present paper investigates the possibility of synergistic interactions between simvastatin and fluoxetine in models of anxiety and depression. We investigated the effects of subchronically administered simvastatin (1 or 10 mg/kg/day combined with fluoxetine (2 or 10 mg/kg at 24, 5, and 1 hour on adult rats before conducting behavioral tests. The results indicate that simvastatin and/or fluoxetine treatment reduces anxiety-like behaviors in the elevated plus-maze and open-field tests. Our results showed that simvastatin and/or fluoxetine induced a significant increase in the swimming activity during the forced swimming test (antidepressant effect, with a concomitant increase in climbing time in simvastatin-treated animals only (noradrenergic activation. We hypothesize that anxiolytic and antidepressant effects of simvastatin and/or fluoxetine produce their behavioral effects through similar mechanisms and provide

  12. Basic Mechanisms Leading to Fatigue Failure of Structural Materials

    Czech Academy of Sciences Publication Activity Database

    Polák, Jaroslav; Petráš, Roman; Mazánová, Veronika

    2016-01-01

    Roč. 69, č. 2 (2016), s. 289-294 ISSN 0972-2815. [International Conference on CREEP, FATIGUE and CREEP-FATIGUE INTERACTION /7./. Kalpakkam, 19.01.2016-22.01.2016] R&D Projects: GA ČR(CZ) GA13-23652S Institutional support: RVO:68081723 Keywords : Damage mechanism * Fatigue crack initiation * Austenitic steel * Oxide cracking Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.533, year: 2016

  13. Mechanical properties of structural materials for high temperature gas cooled reactor

    International Nuclear Information System (INIS)

    Kim, D. W.; Park, J. Y.; Kim, W. G.; Yoon, J. H.

    2011-08-01

    Structural materials for high temperature gas cooled reactor should have good properties such as mechanical properties (tensile, creep, fatigue, creep-fatigue), microstructural stability, interaction between metal and gas, friction and wear, hydrogen and tritium permeation, irradiation behavior, corrosion by impurity in He. Mechanical properties of major structural materials, such as pressure vessel, heat exchanger, control rod, were investigated. Effect of He and irradiation on these structural materials were investigated

  14. Human Birth Weight and Reproductive Immunology: Testing for Interactions between Maternal and Offspring KIR and HLA-C Genes.

    Science.gov (United States)

    Clark, Michelle M; Chazara, Olympe; Sobel, Eric M; Gjessing, Håkon K; Magnus, Per; Moffett, Ashley; Sinsheimer, Janet S

    2016-01-01

    Maternal and offspring cell contact at the site of placentation presents a plausible setting for maternal-fetal genotype (MFG) interactions affecting fetal growth. We test hypotheses regarding killer cell immunoglobulin-like receptor (KIR) and HLA-C MFG effects on human birth weight by extending the quantitative MFG (QMFG) test. Until recently, association testing for MFG interactions had limited applications. To improve the ability to test for these interactions, we developed the extended QMFG test, a linear mixed-effect model that can use multi-locus genotype data from families. We demonstrate the extended QMFG test's statistical properties. We also show that if an offspring-only model is fit when MFG effects exist, associations can be missed or misattributed. Furthermore, imprecisely modeling the effects of both KIR and HLA-C could result in a failure to replicate if these loci's allele frequencies differ among populations. To further illustrate the extended QMFG test's advantages, we apply the extended QMFG test to a UK cohort study and the Norwegian Mother and Child Cohort (MoBa) study. We find a significant KIR-HLA-C interaction effect on birth weight. More generally, the QMFG test can detect genetic associations that may be missed by standard genome-wide association studies for quantitative traits. © 2017 S. Karger AG, Basel.

  15. Drug-laboratory interaction between beta-lactam antibiotics and the galactomannan antigen test used to detect mould infections.

    Science.gov (United States)

    Otting, Kristin A; Stover, Kayla R; Cleary, John D

    2014-01-01

    Several studies have demonstrated that piperacillin/tazobactam produces a false-positive result for the galactomannan antigen test. However, the most recent literature has demonstrated that this interaction is no longer a concern. There is little information regarding the drug-laboratory interaction with the generics of piperacillin/tazobactam or other broad-spectrum beta-lactams, such as ceftaroline, doripenem, imipenem/cilastatin, and meropenem. The purpose of this study was to determine if a drug-laboratory interaction exists with these antibiotics. Tests showed that one lot of imipenem/cilastatin by Hospira Healthcare India Private Limited produced a false-positive result for the galactomannan antigen test. All other medications tested, including piperacillin/tazobactam from seven manufacturers and imipenem/cilastatin by Hospira Inc., did not produce positive results. Since the reason for this drug-laboratory interaction with imipenem/cilastatin is unknown, more studies are needed to further investigate this interaction. Providers also should be educated of these findings: no drug-laboratory interaction with piperacillin/tazobactam and a possible drug-laboratory interaction with imipenem/cilastatin (Hospira Healthcare India Private Limited). Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  16. Experiments in support of the Gas Dynamic Trap based facility for plasma–material interaction testing

    Energy Technology Data Exchange (ETDEWEB)

    Soldatkina, E.I., E-mail: E.I.Soldatkina@inp.nsk.su [Budker Institute of Nuclear Physics SB RAS, Lavrentieva Prospect 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090 (Russian Federation); Arakcheev, A.S.; Bagryansky, P.A. [Budker Institute of Nuclear Physics SB RAS, Lavrentieva Prospect 11, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090 (Russian Federation)

    2013-11-15

    Highlights: • Measurement of plasma heat flux in the mirror of a GDT device had been conducted. • The power density up to 0.25 GW m{sup −2} was experimentally obtained. • Steady state operation has not been achieved due to short NBI pulse. • The possibility of creating the PMI setup based on GDT had been discussed. -- Abstract: The power density along the field lines in the scrape-off layer plasma in machines of the class of ITER, Wendelstein 7-X, NSTX-U is in the range of few hundreds megawatt per square meter. It is crucial for the future of tokamaks and stellarators to develop the plasma science and component technology to handle such high plasma heat fluxes. It would be valuable to produce parallel plasma heat fluxes at these power densities, impinging on test components at very shallow angles, as planned in tokamaks. The primary objective of this work is the direct measurement of plasma heat fluxes in the mirror throat of a Gas Dynamic Trap device. Options to develop a facility for plasma–material interaction testing based on the Gas Dynamic Trap are discussed.

  17. Deuteron beam interaction with lithium jet in a neutron source test facility

    International Nuclear Information System (INIS)

    Hassanein, A.

    1996-01-01

    Testing and evaluating candidate fusion reactor materials in a high-flux, high-energy neutron environment are critical to the success and economic feasibility of a fusion device. The current understanding of materials behavior in fission-like environments and existing fusion facilities is insufficient to ensure the necessary performance of future fusion reactor components. An accelerator-based deuterium-lithium system to generate the required high neutron flux for material testing is considered to be the most promising approach in the near future. In this system, a high-energy (30-40 MeV) deuteron beam impinges on a high-speed (10-20 m/s) lithium jet to produce the high-energy (≥14 MeV) neutrons required to simulate a fusion environment via the Li (d,n) nuclear stripping reaction. Interaction of the high-energy deuteron beam and the subsequent response of the high-speed lithium jet are evaluated in detail. Deposition of the deuteron beam, jet-thermal hydraulic response, lithium-surface vaporization rate, and dynamic stability of the jet are modeled. It is found that lower beam kinetic energies produce higher surface temperature and consequently higher Li vaporization rates. Larger beam sizes significantly reduce both bulk and surface temperatures. Thermal expansion and dynamic velocities (normal to jet direction) due to beam energy deposition and momentum transfer are much lower than jet flow velocity and decrease substantially at lower beam current densities. (orig.)

  18. Acoustic interactions between an altitude test facility and jet engine plumes: Theory and experiments

    Science.gov (United States)

    Ahuja, K. K.; Jones, R. R., III; Tam, C. K.; Massey, K. C.; Fleming, A. J.

    1992-01-01

    The overall objective of the described effort was to develop an understanding of the physical mechanisms involved in the flow/acoustic interactions experienced in full-scale altitude engine test facilities. This is done by conducting subscale experiments and through development of a theoretical model. Model cold jet experiments with an axisymmetric convergent nozzle are performed in a test setup that stimulates a supersonic jet exhausting into a cylindrical diffuser. The measured data consist of detailed flow visualization data and acoustic spectra for a free and a ducted plume. It is shown that duct resonance is most likely responsible by theoretical calculations. Theoretical calculations also indicate that the higher discrete tones observed in the measurements are related to the screech phenomena. Limited experiments on the sensitivity of a free 2-D, C-D nozzle to externally imposed sound are also presented. It is shown that a 2-D, C-D nozzle with a cutback is less excitable than a 2-D C-D nozzle with no cutback. At a pressure ratio of 1.5 unsteady separation from the diverging walls of the nozzle is noticed. This separation switches from one wall to the opposite wall thus providing an unsteady deflection of the plume. It is shown that this phenomenon is related to the venting provided by the cutback section.

  19. INTERACT

    DEFF Research Database (Denmark)

    Jochum, Elizabeth; Borggreen, Gunhild; Murphey, TD

    This paper considers the impact of visual art and performance on robotics and human-computer interaction and outlines a research project that combines puppetry and live performance with robotics. Kinesics—communication through movement—is the foundation of many theatre and performance traditions...... including puppetry and dance. However, the aesthetics of these traditions vary across cultures and carry different associative and interpretive meanings. Puppetry offers a useful frame for understanding the relationship between abstract and imitative gestures and behavior, and instantiates the complex...

  20. Novel Likelihood Ratio Tests for Screening Gene-Gene and Gene-Environment Interactions with Unbalanced Repeated-Measures Data

    Science.gov (United States)

    Ko, Yi-An; Saha-Chaudhuri, Paramita; Park, Sung Kyun; Vokonas, Pantel Steve; Mukherjee, Bhramar

    2013-01-01

    There has been extensive literature on modeling gene-gene interaction (GGI) and gene-environment interaction (GEI) in case-control studies with limited literature on statistical methods for GGI and GEI in longitudinal cohort studies. We borrow ideas from the classical two-way analysis of variance (ANOVA) literature to address the issue of robust modeling of interactions in repeated-measures studies. While classical interaction models proposed by Tukey and Mandel have interaction structures as a function of main effects, a newer class of models, additive main effects and multiplicative interaction (AMMI) models, do not have similar restrictive assumptions on the interaction structure. AMMI entails a singular value decomposition of the cell residual matrix after fitting the additive main effects and has been shown to perform well across various interaction structures. We consider these models for testing GGI and GEI from two perspectives: likelihood ratio test based on cell means and a regression based approach using individual observations. Simulation results indicate that both approaches for AMMI models lead to valid tests in terms of maintaining the type I error rate, with the regression approach having better power properties. The performance of these models was evaluated across different interaction structures and 12 common epistasis patterns. In summary, AMMI model is robust with respect to misspecified interaction structure and is a useful screening tool for interaction even in the absence of main effects. We use the proposed methods to examine the interplay between the hemochromatosis gene and cumulative lead exposure on pulse pressure in the Normative Aging Study. PMID:23798480

  1. Assesing tree-root & soil interaction using pull-out test apparatus

    Science.gov (United States)

    Wibowo, J.; Corcoran, M. K.; Kala, R.; Leavell, D.

    2011-12-01

    Knowing in situ root strength provides a better understanding of the responses of tree root systems against external loads. Root pullout devices are used to record these strengths and can be expressed in two ways: pullout force, which is a direct output from the load cell (measured in pounds) or pullout stress, which is the pullout force divided by root cross section area (measured in pounds per square in.). Pullout tests show not only the possible tensile strength of a tree root, but also the interaction between the tree root and the surrounding geological materials. After discussion with engineers from the University of Nottingham-Trent, the U.S. Army Engineer Research and Development Center (ERDC) constructed a root pullout apparatus with some modifications. These modifications included using a T-System configuration at the base of an aluminum frame instead of a diagonal rod and varying the size of the clamp placed around the tested root. The T-System is placed in front of the root perpendicular to the root path. In the ERDC pullout device, the root was pulled directly without a lever system. A string pot was used to measure displacement when the root was pulled. The device is capable of pulling tree roots with a diameter of up to 2.5 in. and a maximum load of 5000 lbs. Using this device, ERDC conducted field operations in Portland, Oregon; Burlington, Washington; and Albuquerque, New Mexico, on Oregon ash, alder, maple, and cedar trees. In general, pullout tests were conducted approximately 60 deg around the tree selected for the tests. The location of a test depended on the availability of a root near the ground surface. A backhoe was used to remove soil around the tree to locate roots. Before the root was secured in a clamp, root diameter was measured and recorded, and the root was photographed. The tree species, dip angle and dip direction of the root, root location with respect to the tree, tree location, dates, weather, and soil type were also recorded

  2. The Influence of Age on Interaction between Breath-Holding Test and Single-Breath Carbon Dioxide Test

    Directory of Open Access Journals (Sweden)

    Nikita Trembach

    2017-01-01

    Full Text Available Introduction. The aim of the study was to compare the breath-holding test and single-breath carbon dioxide test in evaluation of the peripheral chemoreflex sensitivity to carbon dioxide in healthy subjects of different age. Methods. The study involved 47 healthy volunteers between ages of 25 and 85 years. All participants were divided into 4 groups according to age: 25 to 44 years (n=14, 45 to 60 years (n=13, 60 to 75 years (n=12, and older than 75 years (n=8. Breath-holding test was performed in the morning before breakfast. The single-breath carbon dioxide (SB-CO2 test was performed the following day. Results. No correlation was found between age and duration of breath-holding (r=0.13 and between age and peripheral chemoreflex sensitivity to CO2 (r=0.07. In all age groups there were no significant differences in the mean values from the breath-holding test and peripheral chemoreflex sensitivity tests. In all groups there was a strong significant inverse correlation between breath-holding test and SB-CO2 test. Conclusion. A breath-holding test reflects the sensitivity of the peripheral chemoreflex to carbon dioxide in healthy elderly humans. Increasing age alone does not alter the peripheral ventilatory response to hypercapnia.

  3. The Influence of Age on Interaction between Breath-Holding Test and Single-Breath Carbon Dioxide Test.

    Science.gov (United States)

    Trembach, Nikita; Zabolotskikh, Igor

    2017-01-01

    Introduction . The aim of the study was to compare the breath-holding test and single-breath carbon dioxide test in evaluation of the peripheral chemoreflex sensitivity to carbon dioxide in healthy subjects of different age. Methods . The study involved 47 healthy volunteers between ages of 25 and 85 years. All participants were divided into 4 groups according to age: 25 to 44 years ( n = 14), 45 to 60 years ( n = 13), 60 to 75 years ( n = 12), and older than 75 years ( n = 8). Breath-holding test was performed in the morning before breakfast. The single-breath carbon dioxide (SB-CO 2 ) test was performed the following day. Results . No correlation was found between age and duration of breath-holding ( r = 0.13) and between age and peripheral chemoreflex sensitivity to CO 2 ( r = 0.07). In all age groups there were no significant differences in the mean values from the breath-holding test and peripheral chemoreflex sensitivity tests. In all groups there was a strong significant inverse correlation between breath-holding test and SB-CO 2 test. Conclusion . A breath-holding test reflects the sensitivity of the peripheral chemoreflex to carbon dioxide in healthy elderly humans. Increasing age alone does not alter the peripheral ventilatory response to hypercapnia.

  4. Effects of Metabolic Cage Housing on Rat Behavior and Performance in the Social Interaction Test.

    Science.gov (United States)

    Whittaker, Alexandra L; Lymn, Kerry A; Howarth, Gordon S

    2016-01-01

    Although the metabolic cage is commonly used for housing nonhuman animals in the laboratory, it has been recognized as constituting a unique stressor. Such an environment would be expected to affect behavioral change in animals housed therein. However, few studies have specifically addressed the nature or magnitude of this change. The current study sought to characterize the behavioral time budget of rats in metabolic cage housing in comparison to that of individually housed animals in standard open-top cages. Rats in metabolic cages spent less time moving, manipulating enrichment, and carrying out rearing behaviors, and there was a corresponding shift toward inactivity. In an applied Social Interaction Test, behavioral scoring implied that metabolic cage housing had an anxiogenic effect. In conclusion, metabolic cage housing produces measurable effects on spontaneous and evoked behavior in rats in the laboratory. These behavioral changes may lead to a negative emotional state in these animals, which could have negative welfare consequences. Further research is needed to quantify the existence and magnitude of such an effect on rat well being.

  5. Interaction of radionuclides with argillite from the Eleana Formation on the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Dosch, R.G.; Lynch, A.W.

    1979-02-01

    Distribution coefficients have been determined for {sup 137}Cs, {sup 85}Sr, {sup 144}Ce, {sup 99}Tc, {sup 152}Eu, {sup 238}Pu, {sup 244}Cm, and {sup 243}Am between argillite from the Eleana Formation on the Nevada Test Site (NTS) and several aqueous phases. Radionuclide concentrations in the range of 1 to 0.001 {mu}Ci/ml were used with contact times of 14, 28, and 56 days. Reaction mechanism, concentration effects, exchange capacity, equilibration times, and particle size effects were addressed in a more comprehensive study of the interaction of argillite with Cs in deionized water. The experimental parameters used in the distribution coefficient measurements were based in part on this work. The aqueous phases included a simulated groundwater with composition based on the analysis of a NTS groundwater, the same simulant and deionized water which were pre-equilibrated with powdered argillite, and a groundwater simulant with approximately the same qualitative composition of the NTS simulant, but with a higher ionic strength. A system to provide continuous pH control by CO{sub 2} addition during equilibration of the argillite-solution mixtures was designed and assembled. Initial experiments were done with Cs and Eu and the effects of pH on their distribution coefficients are discussed.

  6. Fluid-structure interaction analysis of the drop impact test for helicopter fuel tank.

    Science.gov (United States)

    Yang, Xianfeng; Zhang, Zhiqiang; Yang, Jialing; Sun, Yuxin

    2016-01-01

    The crashworthiness of helicopter fuel tank is vital to the survivability of the passengers and structures. In order to understand and improve the crashworthiness of the soft fuel tank of helicopter during the crash, this paper investigated the dynamic behavior of the nylon woven fabric composite fuel tank striking on the ground. A fluid-structure interaction finite element model of the fuel tank based on the arbitrary Lagrangian-Eulerian method was constructed to elucidate the dynamic failure behavior. The drop impact tests were conducted to validate the accuracy of the numerical simulation. Good agreement was achieved between the experimental and numerical results of the impact force with the ground. The influences of the impact velocity, the impact angle, the thickness of the fuel tank wall and the volume fraction of water on the dynamic responses of the dropped fuel tank were studied. The results indicated that the corner of the fuel tank is the most vulnerable location during the impact with ground.

  7. Direct and nearby lightning strike interaction with test power distribution lines

    Science.gov (United States)

    Schoene, Jens Daniel

    The interaction of direct and nearby rocket-triggered lightning with two unenergized three-phase power distribution lines of about 800 m length was studied at the International Center for Lightning Research and Testing in Florida. A horizontally-configured line was tested in 1999 and 2000, a vertically-configured line in 2001, 2002, and 2003, and a vertically-configured line with overhead ground wire in 2004. All lines were equipped with arresters and, additionally, in 2003, the vertical line had a polemounted transformer. During the 2000, 2001, and 2002 direct strike experiments, arresters frequently failed, but there was no arrester failures either during the 2003 direct strike experiment when the transformer was on the line or during the 2004 direct strike experiment when the lightning current was injected into the overhead ground wire. All line configurations except the one tested in 2004 commonly exhibited flashovers. The division of return stroke currents for the vertically-configured line was initially similar to the division on the horizontally-configured line (that is, the arresters closest to the strike point conducted the bulk of the impulsive current). After some tens of microseconds the currents in all arresters on the vertically-configured line equalized, while the close arrester currents on the horizontally-configured line still conducted significantly more current than the remote arresters. The lightning current division for direct strikes to a phase conductor is successfully modeled with the Electromagnetic Transient Program (EMTP) for the vertically-configured line and, if the residual voltage of the close arresters is reduced by 20%, successfully modeled for the horizontally-configured line. Currents on the vertically-configured line induced by nearby lightning strikes were measured and compared to results calculated using the LIOV-EMTP96 code. It was found that during a lightning strike 11 m from a grounded line pole, a significant fraction of

  8. Interactions between cask components and content of packaging for the transport of radioactive material during drop tests

    International Nuclear Information System (INIS)

    Quercetti, T.; Ballheimer, V.; Zeisler, P.; Mueller, K.

    2003-01-01

    This paper describes the analytical, numerical and experimental investigations on the phenomenon of interactions between cask components and content of packages for the transport of radioactive material during drop tests required according to the IAEA Regulations for the Safe Transport of Radioactive Material. Radial and axial gaps between cask components and content are usually necessary for thermal reasons but larger gaps can exist because of the geometrical dimensions of the specified content. Consequently interactions between content and cask components (lid system, cask body, etc.) are possible and can not be excluded during drop tests. Interactions in this context are relative movements between cask and content which are mainly due to elastic spring effects after releasing the cask for the free drop. These relative movements can cause interior collisions between content and cask during the main impact of the package onto the unyielding target. Drop tests with various types of Type A and Type B packages fully instrumented with strain gauges and accelerometers showed that these interactions respectively interior collisions can be considerable relating to high forces acting on cask lids, lid bolts and the content. Of course the real quantitative consequences of the interactions depend upon different conditions, among others the drop orientation, the design characteristics of the impact limiters, the dimensions of the gaps, the material characteristics of the contents, etc. . In order to investigate more precisely the phenomenon of interactions BAM carried out finite element calculations for the named casks using the ABAQUS/ Standard and ABAQUS/ Explicit computer code comparing them with results obtained from experiments. Additionally, tests with a simplified model instrumented with accelerometers were carried out accompanied by finite element calculations and analytical calculations using MATHEMATICA. The investigations on the mentioned phenomena of interaction

  9. OECD MCCI 2-D Core Concrete Interaction (CCI) tests : CCI-2 test data report-thermalhydraulic results, Rev. 0 October 15, 2004.

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, M. T.; Lomperski, S.; Kilsdonk, D. J.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program addressed the issue of the ability of water to cool and thermally stabilize a molten core-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. As a follow-on program to MACE, The Melt Coolability and Concrete Interaction Experiments (MCCI) project is conducting reactor material experiments and associated analysis to achieve the following objectives: (1) resolve the ex-vessel debris coolability issue through a program that focuses on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties related to long-term two-dimensional molten core-concrete interactions under both wet and dry cavity conditions. Achievement of these two program objectives will demonstrate the efficacy of severe accident management guidelines for existing plants, and provide the technical basis for better containment designs for future plants. In terms of satisfying these objectives, the Management Board (MB) approved the conduct of two long-term 2-D Core-Concrete Interaction (CCI) experiments designed to provide information in several areas, including: (i) lateral vs. axial power split during dry core-concrete interaction, (ii) integral debris coolability data following late phase flooding, and (iii) data regarding the nature and extent of the cooling transient following breach of the crust formed at the melt-water interface. This data report provides thermal hydraulic test results from the CCI-2 experiment, which was conducted on August 24, 2004. Test specifications for CCI-2 are provided in Table 1-1. This experiment investigated the interaction of a fully oxidized 400 kg

  10. OECD MCCI project 2-D Core Concrete Interaction (CCI) tests : CCI-3 test data report-thermalhydraulic results. Rev. 0 October 15, 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, M. T.; Lomperski, S.; Kilsdonk, D. J.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division); (NRC)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program addressed the issue of the ability of water to cool and thermally stabilize a molten core-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. As a follow-on program to MACE, The Melt Coolability and Concrete Interaction Experiments (MCCI) project is conducting reactor material experiments and associated analysis to achieve the following objectives: (1) resolve the ex-vessel debris coolability issue through a program that focuses on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties related to long-term two-dimensional molten core-concrete interactions under both wet and dry cavity conditions. Achievement of these two program objectives will demonstrate the efficacy of severe accident management guidelines for existing plants, and provide the technical basis for better containment designs for future plants. In terms of satisfying these objectives, the Management Board (MB) approved the conduct of a third long-term 2-D Core-Concrete Interaction (CCI) experiment designed to provide information in several areas, including: (i) lateral vs. axial power split during dry core-concrete interaction, (ii) integral debris coolability data following late phase flooding, and (iii) data regarding the nature and extent of the cooling transient following breach of the crust formed at the melt-water interface. This data report provides thermal hydraulic test results from the CCI-3 experiment, which was conducted on September 22, 2005. Test specifications for CCI-3 are provided in Table 1-1. This experiment investigated the interaction of a fully oxidized 375

  11. OECD MMCI 2-D Core Concrete Interaction (CCI) tests : CCCI-1 test data report-thermalhydraulic results. Rev 0 January 31, 2004.

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, M. T.; Lomperski, S.; Aeschlimann, R. W.; Basu, S. (Nuclear Engineering Division)

    2011-05-23

    The Melt Attack and Coolability Experiments (MACE) program addressed the issue of the ability of water to cool and thermally stabilize a molten core-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. As a follow-on program to MACE, The Melt Coolability and Concrete Interaction Experiments (MCCI) project is conducting reactor material experiments and associated analysis to achieve the following objectives: (1) resolve the ex-vessel debris coolability issue through a program that focuses on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties related to long-term two-dimensional molten coreconcrete interactions under both wet and dry cavity conditions. Achievement of these two program objectives will demonstrate the efficacy of severe accident management guidelines for existing plants, and provide the technical basis for better containment designs for future plants. In terms of satisfying these objectives, the Management Board (MB) approved the conduct of two long-term 2-D Core-Concrete Interaction (CCI) experiments designed to provide information in several areas, including: (i) lateral vs. axial power split during dry core-concrete interaction, (ii) integral debris coolability data following late phase flooding, and (iii) data regarding the nature and extent of the cooling transient following breach of the crust formed at the melt-water interface. This data report provides thermal hydraulic test results from the CCI-1 experiment, which was conducted on December 19, 2003. Test specifications for CCI-1 are provided in Table 1-1. This experiment investigated the interaction of a fully oxidized 400 kg

  12. Robust Tests for Additive Gene-Environment Interaction in Case-Control Studies Using Gene-Environment Independence

    DEFF Research Database (Denmark)

    Liu, Gang; Lee, Seunggeun; Lee, Alice W

    2018-01-01

    There have been recent proposals advocating the use of additive gene-environment interaction instead of the widely used multiplicative scale, as a more relevant public health measure. Using gene-environment independence enhances the power for testing multiplicative interaction in case...... in a data-adaptive way, to the additive scale. An EB estimator of Relative Excess Risk due to Interaction is derived and the corresponding Wald test is proposed with general regression setting under a retrospective likelihood framework. We study the impact of gene-environment association on the resultant...... test with case-control data. Our simulation studies suggest that the EB approach uses the gene-environment independence assumption in a data-adaptive way and provides power gain compared to the standard logistic regression analysis and better control of Type I error when compared to the analysis...

  13. The Influence of Age on Interaction between Breath-Holding Test and Single-Breath Carbon Dioxide Test

    OpenAIRE

    Trembach, Nikita; Zabolotskikh, Igor

    2017-01-01

    Introduction. The aim of the study was to compare the breath-holding test and single-breath carbon dioxide test in evaluation of the peripheral chemoreflex sensitivity to carbon dioxide in healthy subjects of different age. Methods. The study involved 47 healthy volunteers between ages of 25 and 85 years. All participants were divided into 4 groups according to age: 25 to 44 years (n = 14), 45 to 60 years (n = 13), 60 to 75 years (n = 12), and older than 75 years (n = 8). Breath-holding test ...

  14. Barrier erosion control test plan: Gravel mulch, vegetation, and soil water interactions

    Energy Technology Data Exchange (ETDEWEB)

    Waugh, W.J.; Link, S.O. (Pacific Northwest Lab., Richland, WA (USA))

    1988-07-01

    Soil erosion could reduce the water storage capacity of barriers that have been proposed for the disposal of near-surface waste at the US Department of Energy's Hanford Site. Gravel mixed into the top soil surface may create a self-healing veneer that greatly retards soil loss. However, gravel admixtures may also enhance infiltration of rainwater, suppress plant growth and water extraction, and lead to the leaching of underlying waste. This report describes plans for two experiments that were designed to test hypotheses concerning the interactive effects of surface gravel admixtures, revegetation, and enhanced precipitation on soil water balance and plant abundance. The first experiment is a factorial field plot set up on the site selected as a soil borrow area for the eventual construction of barriers. The treatments, arranged in a a split-split-plot design structure, include two densities of gravel admix, a mixture of native and introduced grasses, and irrigation to simulate a wetter climate. Changes in soil water storage and plant cover are monitored with neutron moisture probes and point intercept sampling, respectively. The second experiment consists of an array of 80 lysimeters containing several different barrier prototypes. Surface treatments are similar to the field-plot experiment. Drainage is collected from a valve at the base of each lysimeter tube, and evapotranspiration is estimated by subtraction. The lysimeters are also designed to be coupled to a whole-plant gas exchange system that will be used to conduct controlled experiments on evapotranspiration for modeling purposes. 56 refs., 6 figs., 8 tabs.

  15. Organizational justice and mental health: a multi-level test of justice interactions.

    Science.gov (United States)

    Fischer, Ronald; Abubakar, Amina; Arasa, Josephine Nyaboke

    2014-04-01

    We examine main and interaction effects of organizational justice at the individual and the organizational levels on general health in a Kenyan sample. We theoretically differentiate between two different interaction patterns of justice effects: buffering mechanisms based on trust versus intensifying explanations of justice interactions that involve psychological contract violations. Using a two-level hierarchical linear model with responses from 427 employees in 29 organizations, only interpersonal justice at level 1 demonstrated a significant main effect. Interactions between distributive and interpersonal justice at both the individual and the collective levels were found. The intensifying hypothesis was supported: the relationship between distributive justice and mental health problems was strongest when interpersonal justice was high. This contrasts with buffering patterns described in Western samples. We argue that justice interaction patterns shift depending on the economic conditions and sociocultural characteristics of employees studied. © 2013 International Union of Psychological Science.

  16. Testing the Interacting Dark Energy Model with Cosmic Microwave Background Anisotropy and Observational Hubble Data

    Directory of Open Access Journals (Sweden)

    Weiqiang Yang

    2017-07-01

    Full Text Available The coupling between dark energy and dark matter provides a possible approach to mitigate the coincidence problem of the cosmological standard model. In this paper, we assumed the interacting term was related to the Hubble parameter, energy density of dark energy, and equation of state of dark energy. The interaction rate between dark energy and dark matter was a constant parameter, which was, Q = 3 H ξ ( 1 + w x ρ x . Based on the Markov chain Monte Carlo method, we made a global fitting on the interacting dark energy model from Planck 2015 cosmic microwave background anisotropy and observational Hubble data. We found that the observational data sets slightly favored a small interaction rate between dark energy and dark matter; however, there was not obvious evidence of interaction at the 1 σ level.

  17. Interpretation and calculations for the first series of tests for the ARTEMIS program (corium-concrete interaction with simulating materials)

    International Nuclear Information System (INIS)

    Michel, B.; Cranga, M.

    2009-01-01

    The ARTEMIS experimental program is devoted to the study of corium/concrete interaction performed using simulating materials. The aim of the first series of tests was to study the phenomenology of the corium/concrete interaction, in particular at the interface between the liquid pool and the concrete, versus the heat dissipated in the pool and gas velocity. During this first series of tests, six 1D tests were performed. This interpretation of the experimental results shows that, if gas velocity and heat flux are sufficiently low, a stable crust, made of solid accumulations, builds up at the beginning of the interaction whereas the pool remains liquid. These solid masses are not melted or dissolved afterwards. They are not in thermodynamic equilibrium with the pool. In addition, the quantity of these solid masses depends on the initial superheat of the pool and has a significant impact on the progress of the interaction. If the conditions of crust build-up are not satisfied, the pool is in a semi-solid state. This report identifies the validity limits of a corium/concrete interface description based on the equilibrium phase segregation model and has led to the establishment of the basic features of a new model, suitable for this test series. This consists in considering the solid masses built up at the beginning of the interaction only as thermal resistance. This model has been successfully tested for the 5 reliable tests, using the MEDICIS module of the ASTEC code. The correlation between the experimental results and the calculations confirms this interpretation

  18. Test-retest reliability of an interactive voice response (IVR) version of the EORTC QLQ-C30

    NARCIS (Netherlands)

    Lundy, J.J.; Coons, S.J.; Aaronson, N.K.

    2015-01-01

    Objective: The objective of this study was to assess the test-retest reliability of an interactive voice response (IVR) version of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30. Methods: A convenience sample of outpatient cancer clinic patients (n = 127) was asked to

  19. Reliability and Validity of the Interactive Drawing Test: A Measure of Reciprocity for Children and Adolescents with Autism Spectrum Disorder

    NARCIS (Netherlands)

    Backer van Ommeren, C.; Koot, H.M.; Scheeren, A.M.; Begeer, S.M.

    2015-01-01

    Poor reciprocity is a defining feature of an autism spectrum disorder (ASD). In the current study, we examined the reliability and validity of the Interactive Drawing Test (IDT), a new instrument to assess reciprocal behavior. The IDT was administered to children and adolescents with ASD (n = 131)

  20. Employing think-aloud protocols and constructive interaction to test the usability of online library catalogues: A methodological comparison

    NARCIS (Netherlands)

    Van Den Haak, M. J.; De Jong, M. D T; Schellens, P. J.

    2004-01-01

    This paper describes a comparative study of three usability test approaches: concurrent think-aloud protocols, retrospective think-aloud protocols, and constructive interaction. These three methods were compared by means of an evaluation of an online library catalogue, which involved four points of

  1. Employing think-aloud protocols and constructive interaction to test the usability of online library catalogues: a methodological comparison.

    NARCIS (Netherlands)

    van den Haak, M.J.; de Jong, Menno D.T.; Schellens, P.J.

    2004-01-01

    This paper describes a comparative study of three usability test approaches: concurrent think-aloud protocols, retrospective think-aloud protocols, and constructive interaction. These three methods were compared by means of an evaluation of an online library catalogue, which involved four points of

  2. An R package "VariABEL" for genome-wide searching of potentially interacting loci by testing genotypic variance heterogeneity

    Directory of Open Access Journals (Sweden)

    Struchalin Maksim V

    2012-01-01

    Full Text Available Abstract Background Hundreds of new loci have been discovered by genome-wide association studies of human traits. These studies mostly focused on associations between single locus and a trait. Interactions between genes and between genes and environmental factors are of interest as they can improve our understanding of the genetic background underlying complex traits. Genome-wide testing of complex genetic models is a computationally demanding task. Moreover, testing of such models leads to multiple comparison problems that reduce the probability of new findings. Assuming that the genetic model underlying a complex trait can include hundreds of genes and environmental factors, testing of these models in genome-wide association studies represent substantial difficulties. We and Pare with colleagues (2010 developed a method allowing to overcome such difficulties. The method is based on the fact that loci which are involved in interactions can show genotypic variance heterogeneity of a trait. Genome-wide testing of such heterogeneity can be a fast scanning approach which can point to the interacting genetic variants. Results In this work we present a new method, SVLM, allowing for variance heterogeneity analysis of imputed genetic variation. Type I error and power of this test are investigated and contracted with these of the Levene's test. We also present an R package, VariABEL, implementing existing and newly developed tests. Conclusions Variance heterogeneity analysis is a promising method for detection of potentially interacting loci. New method and software package developed in this work will facilitate such analysis in genome-wide context.

  3. Reliability and validity of an automated computerized visual acuity and stereoacuity test in children using an interactive video game.

    Science.gov (United States)

    Ma, Dae Joong; Yang, Hee Kyung; Hwang, Jeong-Min

    2013-07-01

    To evaluate the test-retest reliability and validity of the new automated computerized distance visual acuity and stereoacuity test for children, which uses an interactive video game. Retrospective, observational case series. A total of 102 children aged between 3 and 7 years underwent the Snellen visual acuity test, the Distance Randot Stereotest, and the new automated computerized distance visual acuity and stereoacuity test. The test-retest reliability and validity of the automated computerized tests were assessed and compared with the Snellen visual acuity test and the Distance Randot Stereotest with frequency distributions of the differences, Bland-Altman plots, and Deming regression. The automated computerized distance visual acuity test had high test-retest reliability (95% limits of agreement ±0.18 logMAR, 90.0% of the differences within 0.2 logMAR) and acceptable validity as compared with the Snellen visual acuity chart (95% limits of agreement ±0.27 logMAR, 81.3% of the differences within 0.2 logMAR). The automated computerized distance stereoacuity test had high test-retest reliability (95% limits of agreement ±0.29 log arc second, 95.1% of the differences within 0.3 log arc second) and acceptable validity as compared with the Distance Randot Stereotest (95% limits of agreement ±0.35 log arc second, 93.9% of the differences within 0.3 log arc second). The new automated computerized distance visual acuity and stereoacuity test, which uses an interactive video game, has good reliability and acceptable validity compared with the Snellen visual acuity chart and the Distance Randot Stereotest. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Consumer interaction strength may limit the diversifying effect of intraspecific competition: a test in alewife (Alosa pseudoharengus).

    Science.gov (United States)

    Jones, Andrew W; Post, David M

    2013-06-01

    Intraspecific competition is considered a principal driver of dietary variation, but empirical studies provide mixed support for this mechanism. Here we link comparative and experimental work testing the effects of competition and resource availability on the dietary variation of the alewife (Alosa pseudoharengus). The alewife, a consumer with extreme effects on its resources, was specifically utilized to additionally test the idea that strong interactions between a consumer and its resources can diminish the diversifying effect of competition. First, we compared the short- and long-term diet measures of wild populations across a wide range of densities. Second, in a pair of large-scale field mesocosm experiments, we explored the influence of competition and interaction strength on alewife dietary variation. Results from a whole-lake comparison and field experiments indicated that increasing competition was negatively correlated with population dietary variation. Further, altering the strength of the interaction between the alewife and its prey via prey supplementation eliminated this negative relationship. Collectively, our results suggest that competitive interactions may not drive dietary diversification in the alewife and, potentially, in other highly effective consumers. Our results also indicate that further consideration of the strength of species interactions (and the consumer traits that underlie them) would improve our understanding of the link between intraspecific competition and variation.

  5. OECD MCCI project long-term 2-D molten core concrete interaction test design report, Rev. 0. September 30, 2002

    International Nuclear Information System (INIS)

    Farmer, M.T.; Kilsdonk, D.J.; Lomperski, S.; Aeschliman, R.W.; Basu, S.

    2011-01-01

    The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core-concrete interaction when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. As a follow-on program to MACE, The Melt Coolability and Concrete Interaction Experiments (MCCI) project is conducting reactor material experiments and associated analysis to achieve the following two technical objectives: (1) resolve the ex-vessel debris coolability issue through a program that focuses on providing both confirmatory evidence and test data for the coolability mechanisms identified in MACE integral effects tests, and (2) address remaining uncertainties related to long-term two-dimensional molten core-concrete interactions under both wet and dry cavity conditions. Achievement of these two objectives will demonstrate the efficacy of severe accident management guidelines for existing plants, and provide the technical basis for better containment designs for future plants. In terms of the first program objective, the Small-Scale Water Ingression and Crust Strength (SSWICS) test series has been initiated to provide fundamental information on the ability of water to ingress into cracks and fissures that form in the debris during quench, thereby augmenting the otherwise conduction-limited heat transfer process. A test plan for Melt Eruption Separate Effects Tests (MESET) has also been developed to provide information on the extent of crust growth and melt eruptions as a function of gas sparging rate under well-controlled experiment conditions. In terms of the second program objective, the project Management Board (MB) has approved startup activities required to carry out

  6. Syndemics of psychosocial problems and HIV risk: A systematic review of empirical tests of the disease interaction concept.

    Science.gov (United States)

    Tsai, Alexander C; Burns, Bridget F O

    2015-08-01

    In the theory of syndemics, diseases co-occur in particular temporal or geographical contexts due to harmful social conditions (disease concentration) and interact at the level of populations and individuals, with mutually enhancing deleterious consequences for health (disease interaction). This theory has widespread adherents in the field, but the extent to which there is empirical support for the concept of disease interaction remains unclear. In January 2015 we systematically searched 7 bibliographic databases and tracked citations to highly cited publications associated with the theory of syndemics. Of the 783 records, we ultimately included 34 published journal articles, 5 dissertations, and 1 conference abstract. Most studies were based on a cross-sectional design (32 [80%]), were conducted in the U.S. (32 [80%]), and focused on men who have sex with men (21 [53%]). The most frequently studied psychosocial problems were related to mental health (33 [83%]), substance abuse (36 [90%]), and violence (27 [68%]); while the most frequently studied outcome variables were HIV transmission risk behaviors (29 [73%]) or HIV infection (9 [23%]). To test the disease interaction concept, 11 (28%) studies used some variation of a product term, with less than half of these (5/11 [45%]) providing sufficient information to interpret interaction both on an additive and on a multiplicative scale. The most frequently used specification (31 [78%]) to test the disease interaction concept was the sum score corresponding to the total count of psychosocial problems. Although the count variable approach does not test hypotheses about interactions between psychosocial problems, these studies were much more likely than others (14/31 [45%] vs. 0/9 [0%]; χ2 = 6.25, P = 0.01) to incorporate language about "synergy" or "interaction" that was inconsistent with the statistical models used. Therefore, more evidence is needed to assess the extent to which diseases interact, either at the

  7. Positive affect predicts avoidance goals in social interaction anxiety: testing a hierarchical model of social goals.

    Science.gov (United States)

    Trew, Jennifer L; Alden, Lynn E

    2012-01-01

    Models of self-regulation suggest that social goals may contribute to interpersonal and affective difficulties, yet little research has addressed this issue in the context of social anxiety. The present studies evaluated a hierarchical model of approach and avoidance in the context of social interaction anxiety, with affect as a mediating factor in the relationship between motivational tendencies and social goals. This model was refined in one undergraduate sample (N = 186) and cross-validated in a second sample (N = 195). The findings support hierarchical relationships between motivational tendencies, social interaction anxiety, affect, and social goals, with higher positive affect predicting fewer avoidance goals in both samples. Implications for the treatment of social interaction anxiety are discussed.

  8. Gender discrimination may be worse than you think: testing ordinal interactions in power research.

    Science.gov (United States)

    Elias, Steven M; Cropanzano, Russell

    2006-04-01

    The authors reanalyze the data of a study by S. M. Elias and R. J. Loomis (2004), which aimed to determine how an instructor's gender may influence his or her ability to gain student compliance. S. M. Elias and R. J. Loomis observed few significant gender effects using traditional multivariate analyses of variance. The authors reanalyze this data using the more appropriate statistical techniques for detecting ordinal interactions recommended by M. J. Strube and P. Bobko (1989) and S. M. Elias (2004). An ordinal interaction occurs when 1 cell of a 2 x 2 design is responsible for a significant interaction (e.g., female instructors suffering only when rated by male students). Reanalysis of the data resulted in more robust findings.

  9. Construction of the thermal/structural interactions in situ tests at the Waste Isolation Pilot Plant (WIPP)

    International Nuclear Information System (INIS)

    Munson, D.E.; Matalucci, R.V.; Hoag, D.L.; Blankenship D.A.

    1997-02-01

    The Department of Energy has constructed the Waste Isolation Pilot Plant (WIPP) to develop the technology for the disposal of radioactive waste from defense programs. Sandia National Laboratories has the responsibility for experimental activities at the WIPP and has emplaced several large-scale Thermal/Structural Interactions (TSI) in situ tests to validate techniques used to predict repository performance. The construction of the tests relied heavily on earlier excavations at the WIPP site to provide a basis for selecting excavation, surveying, and instrumentation methods, and achievable construction tolerances. The tests were constructed within close tolerances to provide consistent room dimensions and accurate placement of gages. This accuracy has contributed to the high quality of data generated which in turn has facilitated the comparison of test results to numerical predictions. The purpose of this report is to detail the construction activities of the TSI tests

  10. The dynamics of molecular interactions and chemical reactions at metal surfaces: testing the foundations of theory.

    Science.gov (United States)

    Golibrzuch, Kai; Bartels, Nils; Auerbach, Daniel J; Wodtke, Alec M

    2015-04-01

    We review studies of molecular interactions and chemical reactions at metal surfaces, emphasizing progress toward a predictive theory of surface chemistry and catalysis. For chemistry at metal surfaces, a small number of central approximations are typically made: (a) the Born-Oppenheimer approximation of electronic adiabaticity, (b) the use of density functional theory at the generalized gradient approximation level, (c) the classical approximation for nuclear motion, and (d) various reduced-dimensionality approximations. Together, these approximations constitute a provisional model for surface chemical reactivity. We review work on some carefully studied examples of molecules interacting at metal surfaces that probe the validity of various aspects of the provisional model.

  11. Leach test methodology for the Waste/Rock Interactions Technology Program

    International Nuclear Information System (INIS)

    Bradley, D.J.; McVay, G.L.; Coles, D.G.

    1980-05-01

    Experimental leach studies in the WRIT Program have two primary functions. The first is to determine radionuclide release from waste forms in laboratory environments which attempt to simulate repository conditions. The second is to elucidate leach mechanisms which can ultimately be incorporated into nearfield transport models. The tests have been utilized to generate rates of removal of elements from various waste forms and to provide specimens for surface analysis. Correlation between constituents released to the solution and corresponding solid state profiles is invaluable in the development of a leach mechanism. Several tests methods are employed in our studies which simulate various proposed leach incident scenarios. Static tests include low temperature (below 100 0 C) and high temperature (above 100 0 C) hydrothermal tests. These tests reproduce nonflow or low-flow repository conditions and can be used to compare materials and leach solution effects. The dynamic tests include single-pass, continuous-flow(SPCF) and solution-change (IAA)-type tests in which the leach solutions are changed at specific time intervals. These tests simulate repository conditions of higher flow rates and can also be used to compare materials and leach solution effects under dynamic conditions. The modified IAEA test is somewhat simpler to use than the one-pass flow and gives adequate results for comparative purposes. The static leach test models the condition of near-zero flow in a repository and provides information on element readsorption and solubility limits. The SPCF test is used to study the effects of flowing solutions at velocities that may be anticipated for geologic groundwaters within breached repositories. These two testing methods, coupled with the use of autoclaves, constitute the current thrust of WRIT leach testing

  12. Experiments on thermal interactions: Tests with Al2O3 droplets and water

    International Nuclear Information System (INIS)

    Peppler, W.; Till, W.; Kaiser, A.

    1991-09-01

    Within the analysis of severe highly hypothetical fast breeder accidents the consequences of a fuel-coolant interaction have to be considered, i.e. the thermal interaction between hot molten fuel and sodium. To improve principal knowledge on the fragmentation process during the interaction of a hot droplet with a cold fluid, a series of experiments was performed with single droplets of molten Al 2 O 3 as the hot liquid and water as the cold and easily volatile fluid. To initiate fragmentation of the droplet pressure pulses of up to 1 MPa were generated in the water by a magnetic hammer. The events were filmed by a high speed camera with up to 10 5 pictures per second. Details of the interactions can be deduced from the films and from the pressure histories. The existence of a vapour trail in all experiments indicates complex heat and mass transfer processes occurring in the vapour film spontaneously formed between droplet and cold fluid. Fragmentation was initiated by local events in the vapour trail area. (orig.) [de

  13. Test of interaction models up to 40 PeV by studying hadronic cores of EAS

    NARCIS (Netherlands)

    Apel, W.D.; Badea, A.F.; Bekk, K.; Blümer, J.; Bozdog, H.; Brancus, I.M.; Daumiller, K.; Doll, P.; Engel, R.; Engler, J.; Gils, H.J.; Glasstetter, R.; Haungs, A.; Heck, D.; Hörandel, J.R.; Kampert, K.H.; Klages, H.O.; Mathes, H.J.; Mayer, H.J.; Milke, J.; Oehlschläger, J.; Ostapchenko, S.; Petcu, M.; Pierog, T.; Rebel, H.; Risse, A.; Risse, M.; Roth, M.; Schatz, G.; Schieler, H.; Ulrich, H.; Buren, J. van; Weindl, A.; Wochele, J.; Zabierowski, J.; Collaboration, T.K.

    2007-01-01

    The interpretation of extensive air shower measurements often requires a comparison with shower simulations in the atmosphere. These calculations rely on hadronic interaction models which have to extrapolate into kinematical and energy regions not explored by present-day collider experiments. The

  14. Thermal mixing tests in a semiannular downcomer with interacting flows from cold legs: International Agreement Report

    Energy Technology Data Exchange (ETDEWEB)

    Tuomisto, H; Mustonen, P

    1986-10-01

    This report describes the test facility and test program for studying thermal mixing of high-pressure injection (HPI) water in the two-fifths scale model of three cold legs, semiannular downcomer and lower plenum of a pressurized water reactor. This test series has been carried out by mutual agreement on the pressurized thermal shock (PTS) information exchange between the US Nuclear Regulation Commission and Imatran Voima Oy. The test facility was originally designed to model the Finnish Loviisa plant but it was redesigned and modified for this test program. The facility can be operated at atmospheric pressure with loop and HPI flows from different cold legs in the area of interest to PTS. Transparent materials were used to allow flow visualization during the tests. The choice of transparent materials limit the upper temperature to 75/sup 0/C. The full buoyancy effect was induced by salt addition and the HPI temperature was used as a tracer. The test matrix consists of 20 tests. The varied parameters were flow rates and the number and configuration of cold legs with HPI and loop flows. Four tests were done with decreasing loop flow temperature to simulate primary flows during steam line breaks.

  15. Testing for interactive and non-linear effects of risk factors for binge eating and purging eating disorders.

    Science.gov (United States)

    Allen, Karina L; Byrne, Susan M; Crosby, Ross D; Stice, Eric

    2016-12-01

    Almost no research has tested whether risk factors interact in the prediction of future eating disorder onset, which might suggest qualitatively distinct etiologic pathways. Accordingly, this prospective study tested for possible interactions between risk factors in the prediction of binge eating and purging eating disorders in adolescents. It also examined sex differences in pathways to risk. Two analytical approaches were used: (1) classification tree analysis (CTA), which is ideally suited to identifying non-linear interactions and the optimal cut-points for defining risk, with follow-up random forest analyses; and (2) two-way interaction terms in a series of logistic regression models. Data were drawn from the Western Australian Pregnancy Cohort (Raine) Study, a population-based study that followed participants from pre-birth to young adulthood. This study involved 1297 adolescents (49% male), 146 (11%) of whom developed bulimia nervosa, binge eating disorder or purging disorder in late adolescence. In CTA, sex was the first and most potent predictor of eating disorder risk with females showing a 5-fold increase in risk relative to males. For males and females, weight and eating concerns were the next most potent predictor of risk and three risk groups emerged, reflecting non-linear risk. For females with intermediate weight and eating concerns, externalizing problems emerged as an additional predictor. Interaction terms in logistic regression models did not produce significant results after correcting for multiple testing. Findings advance knowledge on risk pathways to eating disorder onset, highlight non-linear risk processes, and provide cut-points for prospectively identifying high-risk youth for prevention programs. Copyright © 2016. Published by Elsevier Ltd.

  16. Interactions of skin thickness and physicochemical properties of test compounds in percutaneous penetration studies

    DEFF Research Database (Denmark)

    Wilkinson, Simon C.; Maas, Wilfred J. M.; Nielsen, Jesper Bo

    2006-01-01

    Abstract   Objectives: To determine the effect of skin thickness on the percutaneous penetration and distribution of test compounds with varying physicochemical properties using in vitro systems. Studies were carried out in accordance with OECD guidelines on skin absorption tests. Methods: Percut...

  17. Human-computer interaction in the administration and analysis of neuropsychological tests.

    Science.gov (United States)

    Aharonson, Vered; Korczyn, Amos D

    2004-01-01

    We developed a computerized neuropsychological assessment software, which employs innovative features in both the presentation of the tests and the interpretation of the subjects' performance. The usability features of the software enabled elderly subjects with no computer experience to undergo the cognitive tests, without a test administrator being present. New features extracted from reaction times allowed for enhancement of the performance analysis of the tests. The software was validated using a large group of controls and then administered to a group of subjects with age related memory complaints. The results indicate an improved sensitivity of two of the computerized tests compared with the mini-mental state examination, which enabled to separate two groups of subjects from a population that was relatively homogenous based on clinical history, neurological examination and the mini-mental state examination.

  18. Wing-Body Interaction: Numerical simulation, Wind-tunnel and In-flight Testing

    Czech Academy of Sciences Publication Activity Database

    Popelka, Lukáš; Zelený, L.; Šimurda, David; Matějka, M.

    2010-01-01

    Roč. 34, č. 2 (2010), s. 29-36 ISSN 0744-8996. [OSTIV CONGRESS /29./. Lüsse, 06.08.2008-13.08.2008] R&D Projects: GA MŠk(CZ) 1M06031; GA AV ČR IAA2076403; GA ČR GA101/08/1155 Institutional research plan: CEZ:AV0Z20760514 Keywords : wing-fuselage interaction * turbulent separation * vortex generators Subject RIV: BK - Fluid Dynamics

  19. Haptic, Virtual Interaction and Motor Imagery: Entertainment Tools and Psychophysiological Testing

    OpenAIRE

    Sara Invitto; Chiara Faggiano; Silvia Sammarco; Valerio De Luca; Lucio T. De Paolis

    2016-01-01

    In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user?s hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among u...

  20. Cognitive Function in Adolescence: Testing for Interactions Between Breast-Feeding and "FADS2" Polymorphisms

    Science.gov (United States)

    Martin, Nicolas W.; Benyamin, Beben; Hansell, Narelle K.; Montgomery, Grant W.; Martin, Nicholas G.; Wright, Margaret J.; Bates, Timothy C.

    2011-01-01

    Objectives: Breast-fed C-allele carriers of the rs single nucleotide polymorphism in the fatty acyl desaturase 2 ("FADS2") gene have been reported to show a 6.4 to 7 IQ point advantage over formula-fed C-allele carriers, with no effect of breast-feeding in GG carriers. An Australian sample was examined to determine if an interaction between…

  1. Antiproton interaction with 4He as a test of GUT cosmology

    International Nuclear Information System (INIS)

    Chechetkin, V.M.; Khlopov, M.Yu.; Zeldovich, Ya.B.

    1982-01-01

    A new possibility of checking some GUT models is suggested, basing on the analysis of their cosmological consequences and the experimental study of the anti p 4 He interaction. The study of annihilation of antiprotons with 4 He may provide limits on the possible amount of antimatter in the early Universe, limits on the probability of formation of primordial black holes and restrictions on the GUT parameters determining the properties of domains of antimatter

  2. Association testing to detect gene-gene interactions on sex chromosomes in trio data

    Directory of Open Access Journals (Sweden)

    Yeonok eLee

    2013-11-01

    Full Text Available Autism Spectrum Disorder (ASD occurs more often among males than females in a 4:1 ratio. Among theories used to explain the causes of ASD, the X chromosome and the Y chromosome theories attribute ASD to X-linked mutation and the male-limited gene expressions on the Y chromosome, respectively. Despite the rationale of the theory, studies have failed to attribute the sex-biased ratio to the significant linkage or association on the regions of interest on X chromosome. We further study the gender biased ratio by examining the possible interaction effects between two genes in the sex chromosomes. We propose a logistic regression model with mixed effects to detect gene-gene interactions on sex chromosomes. We investigated the power and type I error rates of the approach for a range of minor allele frequencies and varying linkage disequilibrium between markers and QTLs. We also evaluated the robustness of the model to population stratification. We applied the model to a trio-family data set with an ASD affected male child to study gene-gene interactions on sex chromosomes.

  3. Effect of Soil-Structure Interaction on Seismic Performance of Long-Span Bridge Tested by Dynamic Substructuring Method

    Directory of Open Access Journals (Sweden)

    Zhenyun Tang

    2017-01-01

    Full Text Available Because of the limitations of testing facilities and techniques, the seismic performance of soil-structure interaction (SSI system can only be tested in a quite small scale model in laboratory. Especially for long-span bridge, a smaller tested model is required when SSI phenomenon is considered in the physical test. The scale effect resulting from the small scale model is always coupled with the dynamic performance, so that the seismic performance of bridge considering SSI effect cannot be uncovered accurately by the traditional testing method. This paper presented the implementation of real-time dynamic substructuring (RTDS, involving the combined use of shake table array and computational engines for the seismic simulation of SSI. In RTDS system, the bridge with soil-foundation system is divided into physical and numerical substructures, in which the bridge is seen as physical substructures and the remaining part is seen as numerical substructures. The interface response between the physical and numerical substructures is imposed by shake table and resulting reaction force is fed back to the computational engine. The unique aspect of the method is to simulate the SSI systems subjected to multisupport excitation in terms of a larger physical model. The substructuring strategy and the control performance associated with the real-time substructuring testing for SSI were performed. And the influence of SSI on a long-span bridge was tested by this novel testing method.

  4. Fuel rod-grid interaction wear: in-reactor tests (LWBR development program)

    International Nuclear Information System (INIS)

    Stackhouse, R.M.

    1979-11-01

    Wear of the Zircaloy cladding of LWBR irradiation test fuel rods, resulting from relative motion between rod and rod support contacts, is reported. Measured wear depths were small, 0.0 to 2.7 mils, but are important in fuel element behavior assessment because of the local loss of cladding thickness, as well as the effect on grid spring forces that laterally restrain the rods. An empirical wear analysis model, based on out-of-pile tests, is presented. The model was used to calculate the wear on the irradiation test fuel rods attributed to a combination of up-and-down motions resulting from power and pressure/temperature cycling of the test reactor, flow-induced vibrations, and assembly handling scratches. The calculated depths are generally deeper than the measured depths

  5. Smart Home Test Bed: Examining How Smart Homes Interact with the Power Grid

    Energy Technology Data Exchange (ETDEWEB)

    2016-11-01

    This fact sheet highlights the Smart Home Test Bed capability at the Energy Systems Integration Facility. The National Renewable Energy Laboratory (NREL) is working on one of the new frontiers of smart home research: finding ways for smart home technologies and systems to enhance grid operations in the presence of distributed, clean energy technologies such as photovoltaics (PV). To help advance this research, NREL has developed a controllable, flexible, and fully integrated Smart Home Test Bed.

  6. FY17 Status Report on Testing Supporting the Inclusion of Grade 91 Steel as an Acceptable Material for Application of the EPP Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Messner, Mark C. [Argonne National Lab. (ANL), Argonne, IL (United States); Sham, Sam [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Yanli [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    This report summarizes the experiments performed in FY17 on Gr. 91 steels. The testing of Gr. 91 has technical significance because, currently, it is the only approved material for Class A construction that is strongly cyclic softening. Specific FY17 testing includes the following activities for Gr. 91 steel. First, two types of key feature testing have been initiated, including two-bar thermal ratcheting and Simplified Model Testing (SMT). The goal is to qualify the Elastic – Perfectly Plastic (EPP) design methodologies and to support incorporation of these rules for Gr. 91 into the ASME Division 5 Code. The preliminary SMT test results show that Gr. 91 is most damaging when tested with compression hold mode under the SMT creep fatigue testing condition. Two-bar thermal ratcheting test results at a temperature range between 350 to 650o C were compared with the EPP strain limits code case evaluation, and the results show that the EPP strain limits code case is conservative. The material information obtained from these key feature tests can also be used to verify its material model. Second, to provide experimental data in support of the viscoplastic material model development at Argonne National Laboratory, selective tests were performed to evaluate the effect of cyclic softening on strain rate sensitivity and creep rates. The results show the prior cyclic loading history decreases the strain rate sensitivity and increases creep rates. In addition, isothermal cyclic stress-strain curves were generated at six different temperatures, and a nonisothermal thermomechanical testing was also performed to provide data to calibrate the viscoplastic material model.

  7. Testing Hadronic Interaction Models using a Highly Granular Silicon-Tungsten Calorimeter

    CERN Document Server

    Bilki, B.; Schlereth, J.; Xia, L.; Deng, Z.; Li, Y.; Wang, Y.; Yue, Q.; Yang, Z.; Eigen, G.; Mikami, Y.; Price, T.; Watson, N.K.; Thomson, M.A.; Ward, D.R.; Benchekroun, D.; Hoummada, A.; Khoulaki, Y.; Carloganu, C.; Chang, S.; Khan, A.; Kim, D.H.; Kong, D.J.; Oh, Y.D.; Blazey, G.C.; Dyshkant, A.; Francis, K.; Lima, J.G.R.; Salcido, P.; Zutshi, V.; Boisvert, V.; Green, B.; Misiejuk, A.; Salvatore, F.; Kawagoe, K.; Miyazaki, Y.; Sudo, Y.; Suehara, T.; Tomita, T.; Ueno, H.; Yoshioka, T.; Apostolakis, J.; Folger, G.; Ivantchenko, V.; Ribon, A.; Uzhinskiy, V.; Cauwenbergh, S.; Tytgat, M.; Zaganidis, N.; Hostachy, J.Y.; Morin, L.; Gadow, K.; Göttlicher, P.; Günter, C.; Krüger, K.; Lutz, B.; Reinecke, M.; Sefkow, F.; Feege, N.; Garutti, E.; Laurien, S.; Lu, S.; Marchesini, I.; Matysek, M.; Ramilli, M.; Kaplan, A.; Norbeck, E.; Northacker, D.; Onel, Y.; Kim, E.J.; van Doren, B.; Wilson, G.W.; Wing, M.; Bobchenko, B.; Chadeeva, M.; Chistov, R.; Danilov, M.; Drutskoy, A.; Epifantsev, A.; Markin, O.; Mizuk, R.; Novikov, E.; Popov, V.; Rusinov, V.; Tarkovsky, E.; Besson, D.; Popova, E.; Gabriel, M.; Kiesling, C.; Simon, F.; Soldner, C.; Szalay, M.; Tesar, M.; Weuste, L.; Amjad, M.S.; Bonis, J.; Callier, S.; Conforti di Lorenzo, S.; Cornebise, P.; Doublet, Ph.; Dulucq, F.; Faucci-Giannelli, M.; Fleury, J.; Frisson, T.; Kégl, B.; van der Kolk, N.; Li, H.; Martin-Chassard, G.; Richard, F.; de la Taille, Ch.; Pöschl, R.; Raux, L.; Rouëne, J.; Seguin-Moreau, N.; Anduze, M.; Balagura, V.; Becheva, E.; Boudry, V.; Brient, J.-C.; Cornat, R.; Frotin, M.; Gastaldi, F.; Magniette, F.; Matthieu, A.; Mora de Freitas, P.; Videau, H.; Augustin, J.-E.; David, J.; Ghislain, P.; Lacour, D.; Lavergne, L.; Zacek, J.; Cvach, J.; Gallus, P.; Havranek, M.; Janata, M.; Kvasnicka, J.; Lednicky, D.; Marcisovsky, M.; Polak, I.; Popule, J.; Tomasek, L.; Tomasek, M.; Ruzicka, P.; Sicho, P.; Smolik, J.; Vrba, V.; Zalesak, J.; Jeans, D.; Götze, M.

    2015-09-11

    A detailed study of hadronic interactions is presented using data recorded with the highly granular CALICE silicon-tungsten electromagnetic calorimeter. Approximately 600,000 selected negatively changed pion events at energies between 2 and 10 GeV have been studied. The predictions of several physics models available within the GEANT4 simulation tool kit are compared to this data. Although a reasonable overall description of the data is observed, there are significant quantitative discrepancies in the longitudinal and transverse distributions of reconstructed energy.

  8. Editorial Perspective: Integrating exploratory and competitive-confirmatory approaches to testing person × environment interactions.

    Science.gov (United States)

    Belsky, Jay; Widaman, Keith

    2018-03-01

    Students of child development and of psychopathology have long been interested in how person characteristics (e.g. genotype, temperament) might moderate the effect of environmental exposures (e.g. harsh parenting, negative life events) on development. Historically, most such research on person × environment interaction has been guided by diathesis-stress thinking, which stipulates that some individuals, due to their personal characteristics, are more susceptible to the adverse effects of contextual risk than are others (but do not function differently under supportive or even benign conditions). © 2018 Association for Child and Adolescent Mental Health.

  9. The Hualien Large-Scale Seismic Test for soil-structure interaction research

    International Nuclear Information System (INIS)

    Tang, H.T.; Stepp, J.C.; Cheng, Y.H.

    1991-01-01

    A Large-Scale Seismic Test (LSST) Program at Hualien, Taiwan, has been initiated with the primary objective of obtaining earthquake-induced SSI data at a stiff soil site having similar prototypical nuclear power plant soil conditions. Preliminary soil boring, geophysical testing and ambient and earthquake-induced ground motion monitoring have been conducted to understand the experiment site conditions. More refined field and laboratory tests will be conducted such as the state-of-the-art freezing sampling technique and the large penetration test (LPT) method to characterize the soil constitutive behavior. The test model to be constructed will be similar to the Lotung model. The instrumentation layout will be designed to provide data for studies of SSI, spatial incoherence, soil stability, foundation uplifting, ground motion wave field and structural response. A consortium consisting of EPRI, Taipower, CRIEPI, TEPCO, CEA, EdF and Framatome has been established to carry out the project. It is envisaged that the Hualien SSI array will be ready to record earthquakes by the middle of 1992. The duration of the recording scheduled for five years. (author)

  10. Research, development, and preliminary testing of interactive engagements for teaching quantum mechanics to undergraduate physics majors

    Science.gov (United States)

    Axmann, Waldemar Jay

    The Advanced Visual Quantum Mechanics project was conceived to provide computer-centered, activities-based instructional materials to upper-level undergraduate physics majors. This study implements one curriculum development cycle of research, development, and classroom testing for a single unit, The Shape and Behavior of the Wave Function, of these materials. It is designed to be a proof of concept pilot study for the project. The cycle began with an extensive review of existing research drawing on results from the general fields of cognitive science and educational research as well as more specific research regarding the use of computers in instruction and the teaching and learning of quantum mechanics. It continued with the development of written materials, a computer program, and assessment instruments all extensively based on this research. It concluded with a field test garnering an outcome of positive student and instructor attitudes and perceptions of learning gains as well as actual gains similar or superior to traditional instruction---even in the face of usage that diverged widely from that intended. Based on these results, we recommend the continuation of the Advanced Visual Quantum Mechanics project. This work would include further testing and revision of these materials, similar development and classroom testing of further materials, and new research within the context of that testing. Consideration should also be given to similar projects that address other physics subject areas.

  11. Instrumentation of the thermal/structural interactions in situ tests at the Waste Isolation Pilot Plant (WIPP)

    Energy Technology Data Exchange (ETDEWEB)

    Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States). Repository Isolation Systems Div.; Hoag, D.L.; Blankenship, D.A.; DeYonge, W.F.; Schiermeister, D.M. [RE/SPEC, Inc., Albuquerque, NM (United States); Jones, R.L.; Baird, G.T. [Tech Reps, Inc., Albuquerque, NM (United States)

    1997-04-01

    The Department of Energy has constructed the Waste Isolation Pilot Plant (WIPP) to develop the technology for the disposal of radioactive waste from defense programs. Sandia National Laboratories had the responsibility for the experimental activities at the WIPP and fielded several large-scale Thermal/Structural Interactions (TSI) in situ tests to validate techniques used to predict repository performance. The instrumentation of these tests involved the placement of over 4,200 gages including room closure gages, borehole extensometers, stress gages, borehole inclinometers, fixed reference gages, borehole strain gages, thermocouples, thermal flux meters, heater power gages, environmental gages, and ventilation gages. Most of the gages were remotely read instruments that were monitored by an automated data acquisition system, but manually read instruments were also used to provide early deformation information and to provide a redundancy of measurement for the remote gages. Instruments were selected that could operate in the harsh environment of the test rooms and that could accommodate the ranges of test room responses predicted by pretest calculations. Instruments were tested in the field prior to installation at the WIPP site and were modified to improve their performance. Other modifications were made to gages as the TSI tests progressed using knowledge gained from test maintenance. Quality assurance procedures were developed for all aspects of instrumentation including calibration, installation, and maintenance. The instrumentation performed exceptionally well and has produced a large quantity of quality information.

  12. Instrumentation of the thermal/structural interactions in situ tests at the Waste Isolation Pilot Plant (WIPP)

    International Nuclear Information System (INIS)

    Munson, D.E.; Jones, R.L.; Baird, G.T.

    1997-04-01

    The Department of Energy has constructed the Waste Isolation Pilot Plant (WIPP) to develop the technology for the disposal of radioactive waste from defense programs. Sandia National Laboratories had the responsibility for the experimental activities at the WIPP and fielded several large-scale Thermal/Structural Interactions (TSI) in situ tests to validate techniques used to predict repository performance. The instrumentation of these tests involved the placement of over 4,200 gages including room closure gages, borehole extensometers, stress gages, borehole inclinometers, fixed reference gages, borehole strain gages, thermocouples, thermal flux meters, heater power gages, environmental gages, and ventilation gages. Most of the gages were remotely read instruments that were monitored by an automated data acquisition system, but manually read instruments were also used to provide early deformation information and to provide a redundancy of measurement for the remote gages. Instruments were selected that could operate in the harsh environment of the test rooms and that could accommodate the ranges of test room responses predicted by pretest calculations. Instruments were tested in the field prior to installation at the WIPP site and were modified to improve their performance. Other modifications were made to gages as the TSI tests progressed using knowledge gained from test maintenance. Quality assurance procedures were developed for all aspects of instrumentation including calibration, installation, and maintenance. The instrumentation performed exceptionally well and has produced a large quantity of quality information

  13. Load converter interactions with the secondary system in the Space Station Freedom power management and distribution DC test bed

    Science.gov (United States)

    Lebron, Ramon C.

    1992-01-01

    The NASA LeRC in Cleveland, Ohio, is responsible for the design, development, and assembly of the Space Station Freedom (SSF) Electrical Power System (EPS). In order to identify and understand system level issues during the SSF Program design and development phases, a system Power Management and Distribution (PMAD) DC test bed was assembled. Some of the objectives of this test bed facility are the evaluation of, system efficiency, power quality, system stability, and system protection and reconfiguration schemes. In order to provide a realistic operating scenario, dc Load Converter Units are used in the PMAD dc test bed to characterize the user interface with the power system. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. This final regulation is required on the actual space station because the majority of user loads will require voltage levels different from the secondary bus voltage. This paper describes the testing of load converters in an end to end system environment (from solar array to loads) where their interactions and compatibility with other system components are considered. Some of the system effects of interest that are presented include load converters transient behavior interactions with protective current limiting switchgear, load converters ripple effects, and the effects of load converter constant power behavior with protective features such as foldback.

  14. Water-rock interaction in CO2 sequestration in a depleted oil reservoir pilot test

    International Nuclear Information System (INIS)

    Pang, Zhonghe; Kong, Yanlong; Li, Yiman; Li, Jie

    2013-01-01

    A field test of CO 2 sequestration in the Neogene Minghuazhen Formation in the Bohai Bay Basin (BBB-Nm test) is presented, where the first Chinese pilot project of CO 2 storage in a depleted oil reservoir was implemented. A total of 305 t CO 2 was injected into the sandstone reservoir. The process of injection and pre/post-injection monitoring are described, especially for the geochemical monitoring in the field test. Results show that CO 2 flux monitoring successfully tracked the injected CO 2 . Chemical analyses of post-injection brine samples indicate brine may have not been affected by CO 2 injection during the monitoring period, which needs to be confirmed with further investigations before extending the results to deep saline aquifers. (authors)

  15. Usability Testing of a Collaborative and Interactive University on a Mobile Device

    Directory of Open Access Journals (Sweden)

    Gavin McArdle

    2009-10-01

    Full Text Available Abstract - The use of mobile devices for delivering learning tools is an attractive concept. Termed mobile learning (m-learning, this new technology allows people to participate in learning activities without being tied to a fixed location and provides users with convenient and flexible access to learning resources anytime and anywhere. While many m-learning applications have been developed to date, most provide tools to help students’ with specific learning tasks rather than a general interface to online courses. Few sup-port online learning communities or allow users to download multimedia learning content. These features would engage mobile users and enable them to interact with one another, thus allowing them to participate in group learning activities despite their changing location. In this article, we describe an m-learning system which we have developed which aims to incorporate these facilities. This system provides access to multimedia learning resources and supports mobile users in an interactive synchronous learning environment with their desktop peers. Details of the evaluation techniques which we utilised to appraise the system are provided and the results are presented. Feedback suggests that the features offered by our system are beneficial for collaborative m-learning.

  16. Overview of QTL detection in plants and tests for synergistic epistatic interactions.

    Science.gov (United States)

    Jannink, Jean-Luc; Moreau, Laurence; Charmet, Gilles; Charcosset, Alain

    2009-06-01

    Improvements in the usefulness of QTL analysis arise from better statistical methods applied to the problem, ability to analyze more complex mating designs, and the fitting of less simplified genetic models. Here we review the advantages of different plant mating designs in QTL analysis and conclude that diallel designs have several favorable properties. We then turn to the detection of systematic genome-wide synergistic epistasis. This form of epistasis has important implications from evolutionary (maintenance of sexual reproduction and concealment of cryptic genetic variation) and practical perspectives (response to pyramided favorable alleles). We develop two methods for detecting systematic synergistic epistasis, one based on analyzing interactions between locus effects and predicted individual genotypic values and one based on analyzing pairwise locus interactions. Using the first method we detect synergistic epistasis in a barley and a wheat dataset but not in a maize dataset. We fail to detect synergistic epistasis with the second method. We discuss our results in the light of theoretical questions concerning the mechanisms of synergistic epistasis.

  17. The Interaction between Language and Culture: A Test of the Cultural Accommodation Hypothesis in Seven Countries.

    Science.gov (United States)

    Harzing, Anne-Wil; Maznevski, Martha

    2002-01-01

    Investigates the cultural accommodation hypothesis in questionnaire-based research: Do respondents adjust their responses in a way that reflects the cultural values associated with the language of the questionnaire. A test of this hypothesis with a sample of university students in seven countries indicates that cultural accommodation plays an…

  18. Understanding the Interaction between High-Stakes Graduation Tests and English Learners

    Science.gov (United States)

    Heilig, Julian Vasquez

    2011-01-01

    Background/Context: The prevailing theory of action underlying No Child Left Behind's high-stakes testing and accountability ratings is that schools and students held accountable to these measures will automatically increase educational output as educators try harder, schools will adopt more effective methods, and students will learn more. In…

  19. Child-Robot Interaction in the Wild : Field Testing Activities of the ALIZ-E Project

    NARCIS (Netherlands)

    Greeff, J. de; Blanson Henkemans, O.A.; Fraaije, A.; Solms, L.; Wigdor, N.; Bierman, B.

    2014-01-01

    A field study was conducted in which CRI activities developed by the ALIZ-E project were tested with the project's primary user group: children with diabetes. This field study resulted in new insights in the modalities and roles a robot aimed at CRI in a healthcare setting might utilise, while in

  20. Consumer Perceptions of Interactions With Primary Care Providers After Direct-to-Consumer Personal Genomic Testing

    NARCIS (Netherlands)

    van der Wouden, Cathelijne H.; Carere, Deanna Alexis; Maitland-van der Zee, Anke H.; Ruffin, Mack T.; Roberts, J. Scott; Green, Robert C.; IV, Mack T. Ruffin; Krier, Joel B.; Helm, Margaret H.; Lehmann, Lisa S.; Kraft, Peter; Le, Lan Q.; Ostergren, Jenny; Uhlmann, Wendy R.; Couper, Mick P.; Mountain, Joanna L.; Kiefer, Amy K.; Braunstein, Glenn D.; Crawford, Scott D.; Cupples, L. Adrienne; Chen, Clara A.; Wang, Catharine; Gray, Stacy W.; Koenig, Barbara A.; Kaphingst, Kimberly; Gollust, Sarah

    2016-01-01

    Background: Direct-to-consumer (DTC) personal genomic testing (PGT) allows individuals to learn about their genetic makeup without going through a physician, but some consumers share their results with their primary care provider (PCP). Objective: To describe the characteristics and perceptions of

  1. Tensile testing study of dynamic interactions between dislocations and precipitate in vanadium alloys

    International Nuclear Information System (INIS)

    Tougou, Kouichi; Nogiwa, Kimihiro; Tachikawa, Kazuhiro; Fukumoto, Ken-ichi

    2013-01-01

    To investigate the hardening of fine Ti(OCN) precipitate, we performed in situ transmission electron microscopy (TEM) observations during tensile testing of dislocations gliding through fine Ti(OCN) precipitates in thermally aged V–4Cr–4Ti alloys. The obstacle strength parameter was estimated from the critical bow-out angle, ϕ, of the dislocation lines from the microstructural change during tensile deformation observed in the TEM images. From image processing analysis of the dislocation motion, the value of the obstacle strength parameter of Ti(OCN) precipitates of 4-nm size was determined to be 0.30. The increase in yield stress calculated from the measured dislocation behavior pinned around precipitates was Δσ in situ = 43 MPa, and the increase in yield stress measured by the micro-Vickers hardness test was Δσ HV = 49.5 MPa. Data from in situ TEM observations during tensile testing and from micro-Vickers hardness tests were in good agreement; thus, the obstacle strength parameter of the Ti(OCN) precipitates of 4-nm size was successfully obtained experimentally. The obstacle strength parameter also was compared with data from a previous study, and there was also quite good agreement. Therefore, the obstacle strength parameter obtained from this study is measurable and is a reliable measure of mechanical property changes following precipitation in V–4Cr–4Ti alloys

  2. Genotype x environment interaction for grain yield of wheat genotypes tested under water stress conditions

    International Nuclear Information System (INIS)

    Sail, M.A.; Dahot, M.U.; Mangrio, S.M.; Memon, S.

    2007-01-01

    Effect of water stress on grain yield in different wheat genotypes was studied under field conditions at various locations. Grain yield is a complex polygenic trait influenced by genotype, environment and genotype x environment (GxE) interaction. To understand the stability among genotypes for grain yield, twenty-one wheat genotypes developed Through hybridization and radiation-induced mutations at Nuclear Institute of Agriculture (NIA) TandoJam were evaluated with four local check varieties (Sarsabz, Thori, Margalla-99 and Chakwal-86) in multi-environmental trails (MET/sub s/). The experiments were conducted over 5 different water stress environments in Sindh. Data on grain yield were recorded from each site and statistically analyzed. Combined analysis of variance for all the environments indicated that the genotype, environment and genotype x environment (GxE) interaction were highly significant (P greater then 0.01) for grain yield. Genotypes differed in their response to various locations. The overall highest site mean yield (4031 kg/ha) recorded at Moro and the lowest (2326 kg/ha) at Thatta. Six genotypes produced significantly (P=0.01) the highest grain yield overall the environments. Stability analysis was applied to estimate stability parameters viz., regression coefficient (b), standard error of regression coefficient and variance due to deviation from regression (S/sub 2/d) genotypes 10/8, BWS-78 produced the highest mean yield over all the environments with low regression coefficient (b=0.68, 0.67 and 0.63 respectively and higher S/sup 2/ d value, showing specific adaptation to poor (un favorable) environments. Genotype 8/7 produced overall higher grain yield (3647 kg/ha) and ranked as third high yielding genotype had regression value close to unity (b=0.9) and low S/sup d/ value, indicating more stability and wide adaptation over the all environments. The knowledge of the presence and magnitude of genotype x environment (GE) interaction is important to

  3. Interactive education based on haptic technologies and educational testing of an innovative system

    Directory of Open Access Journals (Sweden)

    Theodore S. Papatheodorou

    2008-05-01

    Full Text Available This work presents on the one hand, the specifications and design of an educational haptic device and an educational platform and on the other hand, the educational trial of the applications that specially constructed in order to use this advanced virtual reality system. Α new haptic device designed especially for educational purposes and a prototype were implemented, under the framework of an IST European program called MUVII. This device is called Haptic-3D-Interface (H3DI. The novelty on this device is the tactile feedback that provides minute detailed information about the nature of virtual objects handled, in addition to force and torque feedback. The device was integrated into an innovative platform called Interactive Kiosk Demonstrator (IKD. IKD’s aim was to demonstrate new interactive paradigms forming a novel integration of the following modalities: 3D-vision, 3D-audio and haptic (force, torque, and tactile feedback. Besides, interactive educational software especially designed for IKD platform was developed. Then the educational trial of the IKD system, as well as the educational software, took place. All schools that participated in the trial were randomly selected. A total of 163 students participated in the educational trial, 64 of which were primary school students, 74 were lower-secondary school students, and 25 were upper secondary school students. For the educational trail all the international accepted practices concerning research in education were followed. The “exercises” for each group of students were chosen in accordance to their age. The educational results of this teaching approach, as well as the feedback derived from the users are presented in this work. Furthermore, some interesting results concerning important requirements for the specifications for haptic devices are also presented. Overall, we can state that the opportunity of having a natural “look and feel

  4. Supra-Additive Interaction of Docosahexaenoic Acid and Naproxen and Gastric Safety on the Formalin Test in Rats.

    Science.gov (United States)

    Arroyo-Lira, Arlette Guadalupe; Rodríguez-Ramos, Fernando; Ortiz, Mario I; Castañeda-Hernández, Gilberto; Chávez-Piña, Aracely Evangelina

    2017-11-01

    Preclinical Research The aim of this work was to evaluate the effect of docosahexaenoic acid (DHA) on the pharmacokinetics and pharmacodynamics-nociception-of naproxen in rats, as well as to determine the gastric safety resulting from this combination versus naproxen alone. Female Wistar rats were orally administered DHA, naproxen or the DHA-naproxen mixture at fixed-ratio combination of 1:3. The antinociceptive effect was evaluated using the formalin test. The gastric injury was determined 3 h after naproxen administration. An isobolographic analysis was performed to characterize the antinociceptive interaction between DHA and naproxen. To determine the possibility of pharmacokinetic interactions, the oral bioavailability of naproxen was evaluated in presence and absence of oral DHA. The experimental effective dose ED 30 values (Zexp) were decreased from theoretical additive dose values (Zadd; P supra-additive interaction. The oral administration of DHA increased the pharmacokinetic parameter AUC 0- t of naproxen (P supra-additive antinociceptive effect in the formalin test so that this combination could be useful to management of inflammatory pain. Drug Dev Res 78 : 332-339, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Severe transient tests on operating steam generator: analysis of the fluid-structure dynamic thermal interaction

    International Nuclear Information System (INIS)

    David, J.; Procaccia, H.; Billon, F.

    1983-08-01

    The operating efficiency of steam generators (S.G.s) and their structural integrity depend on the design configurations of the feedwater spray within the S.G., and on the operating procedure. To check the merit of some design modifications, and to verify the fluid-structure interaction with a view to preserve the S.G.s integrity during severe operating transients, a special instrumentation that admits the determination of the instantaneous thermal hydraulic characteristics of the flow in the secondary water and the corresponding metal temperature, in particular in the S.G. downcomer and near the S.G. tube sheet, has been installed by EDF on one steam generator of Tricastin unit 1 power plant. In parallel, FRAMATOME has developped a computer code, TEMPTRON, that allows the calculation of the thermal loads and the consequent stresses in the most sollicited zones of the steam generator during transient operation of the plant

  6. The clinical application of UGT1A1 pharmacogenetic testing: Gene-environment interactions

    Directory of Open Access Journals (Sweden)

    Marques Sara

    2010-04-01

    Full Text Available Abstract Over the past decade, the number of pharmacogenetic tests has increased considerably, allowing for the development of our knowledge of their clinical application. The uridine diphosphate glucuronosyltransferase 1A1 gene (UGT1A1 assay is an example of a pharmacogenetic test. Numerous variants have been found in UGT1A1, the main conjugating enzyme of bilirubin and drugs such as the anticancer drug irinotecan. Recently, the US Food and Drug Administration (FDA recommended testing for the presence of UGT1A1*28, an allele correlated with decreased transcriptional activity, to predict patients at risk of irinotecan toxicity. The administration of other drugs -- such as inhibitors of the UGT1A1 enzyme -- can clinically mimic the *28 phenotype, whereas inducers of UGT1A1 can increase the glucuronidation rate of the enzyme. The *28 polymorphism is not present in all ethnicities at a similar frequency, which suggests that it is important to study different populations to determine the clinical relevance of testing for UGT1A1*28 and to identify other clinically relevant UGT1A1 variants. Environmental factors such as lifestyle can also affect UGT1A1 activity. This review is a critical analysis of studies on drugs that can be affected by the presence of UGT1A1*28, the distribution of this polymorphism around the globe, distinct variants that may be clinically significant in African and Asian populations and how lifestyle can affect treatment outcomes that depend on UGT1A1 activity.

  7. Evaluation of interactions between soil and coal fly ash leachates using column percolation tests.

    Science.gov (United States)

    Tsiridis, V; Petala, M; Samaras, P; Sakellaropoulos, G P

    2015-09-01

    The aim of this work was the assessment of the environmental impact of different origin fly ashes with regard to their final disposal. The experimental procedure included the performance of single column tests and column tests of fly ash and soil in series. The appraisal of the potential environmental hazards was implemented using physicochemical analyses and bioassays. Two different fly ash samples were examined, one fly ash produced from the combustion of sub-bituminous coal (CFA) and one fly ash produced from the combustion of lignite (LFA). Single column percolation tests were performed according to NEN 7343 protocol, while fly ash/soil experiments were conducted incorporating slight modifications to this protocol. The study focused on the release of metals Ba, Cr, Cu, Mo, Se and Zn and the ecotoxic behavior of leachates on crustacean Daphnia magna and bacteria Vibrio fischeri. The infiltration of the leachates of both fly ashes through soil affected considerably their leaching profile. The transport of Cu and Zn was facilitated by the dynamic leaching conditions and influenced by the pH of the leachates. Moreover, the release and bioavailability of Cr, Cu and Zn was probably altered during the infiltration experiments and organisms' response was not always correlated with the concentration of metals. Nevertheless, the results are signalling that possible manipulations and final disposal of fly ash should be considered when environmental threats are investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Intermediate-scale tests of sodium interactions with calcite and dolomite aggregate concretes

    International Nuclear Information System (INIS)

    Randich, E.; Acton, R.U.

    1983-09-01

    Two intermediate-scale tests were performed to compare the behavior of calcite and dolomite aggregate concretes when attacked by molten sodium. The tests were performed as part of an interlaboratory comparison between Sandia National Laboratories and Hanford Engineering Development Laboratories. Results of the tests at Sandia National Laboratories are reported here. The results show that both concretes exhibit similar exothermic reactions with molten sodium. The large difference in reaction vigor suggested by thermodynamic considerations of CO 2 release from calcite and dolomite was not realized. Penetration rates of 1.4 to 1.7 mm/min were observed for short periods of time with reaction zone temperatures in excess of 800 0 C during the energetic attack. The penetration was not uniform over the entire sodium-concrete contact area. Rapid attack may be localized due to inhomogeneities in the concrete. The chemical reaction zone is less then one cm thick for the calcite concrete but is about seven cm thick for the dolomite concrete

  9. Intermediate-scale tests of sodium interactions with calcite and dolomite aggregate concretes. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Randich, E.; Acton, R.U.

    1983-09-01

    Two intermediate-scale tests were performed to compare the behavior of calcite and dolomite aggregate concretes when attacked by molten sodium. The tests were performed as part of an interlaboratory comparison between Sandia National Laboratories and Hanford Engineering Development Laboratories. Results of the tests at Sandia National Laboratories are reported here. The results show that both concretes exhibit similar exothermic reactions with molten sodium. The large difference in reaction vigor suggested by thermodynamic considerations of CO/sub 2/ release from calcite and dolomite was not realized. Penetration rates of 1.4 to 1.7 mm/min were observed for short periods of time with reaction zone temperatures in excess of 800/sup 0/C during the energetic attack. The penetration was not uniform over the entire sodium-concrete contact area. Rapid attack may be localized due to inhomogeneities in the concrete. The chemical reaction zone is less then one cm thick for the calcite concrete but is about seven cm thick for the dolomite concrete.

  10. Interaction between dexibuprofen and dexketoprofen in the orofacial formalin test in mice.

    Science.gov (United States)

    Miranda, H F; Noriega, V; Sierralta, F; Prieto, J C

    2011-01-01

    Animal models are used to research the mechanisms of pain and to mimic human pain. The purpose of this study was to determine the degree of interaction between dexketoprofen and dexibuprofen, by isobolographic analysis using the formalin orofacial assay in mice. This assay presents two-phase time course: an early short-lasting, phase I, starting immediately after the formalin injection producing a tonic acute pain, leaving a 15 min quiescent period, followed by a prolonged, phase II, after the formalin and representing inflammatory pain. Administration of dexketoprofen or dexibuprofen produced a dose-dependent antinociception, with different potency, either during phases I or II. The co-administration of dexketoprofen and dexibuprofen produced synergism in phase I and II. In conclusion, both dexketoprofen and dexibuprofen are able to induce antinociception in the orofacial formalin assay. Their co-administration produced a synergism, which could be related to the different degree of COX inhibition and other mechanisms of analgesics. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Haptic, Virtual Interaction and Motor Imagery: Entertainment Tools and Psychophysiological Testing

    Science.gov (United States)

    Invitto, Sara; Faggiano, Chiara; Sammarco, Silvia; De Luca, Valerio; De Paolis, Lucio T.

    2016-01-01

    In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user’s hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects). After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP) components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning. PMID:26999151

  12. Haptic, Virtual Interaction and Motor Imagery: Entertainment Tools and Psychophysiological Testing.

    Science.gov (United States)

    Invitto, Sara; Faggiano, Chiara; Sammarco, Silvia; De Luca, Valerio; De Paolis, Lucio T

    2016-03-18

    In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user's hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects). After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP) components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning.

  13. Metals interaction tested in children’s hair originating from industrial and rural areas

    Directory of Open Access Journals (Sweden)

    Jerzy Kwapulinski

    2014-09-01

    Full Text Available Introduction. Different biological samples (blood, gallstone, teeth, hair serve as a biomarker of exposure to metals for many years. This method appeared to be useful not only in clinical medicine, but also in the studies on the environment. Aim. The study is to compare the amount of selected metals in children’s hair residing in industrial and rural areas. Material and methods. Research of occurrence of 12 metals in children’s hair at the age of 7, 10 and 14 living in an industrial (Nowy Bytom town and a rural (Strumień town areas has been presented. Determination of Pb, Cd, Ni, Co Na, K, Mg, Zn, Cu, Mn, Fe and Ca was carried out by atomic absorption spectrophotometry (AAS using a spectrometer PerkinElmer 400. Results. In the case of seven-year old children, regardless of gender a common mechanism of co-occurrence was noticed for manganese and calcium, manganese and magnesium, calcium and magnesium, sodium and potassium. Apart from the correlation of metals for the seven-year-old-children mentioned, in case of ten-year old children, an additional correlation between calcium and zinc appears. Conclusion: The amount of some metals in the hair with the diversified possibility of interaction between the metals themselves and their relation to gender and age of children revealed different environmental exposure.

  14. Glia-neuron interactions in neurological diseases: Testing non-cell autonomy in a dish.

    Science.gov (United States)

    Meyer, Kathrin; Kaspar, Brian K

    2017-02-01

    For the past century, research on neurological disorders has largely focused on the most prominently affected cell types - the neurons. However, with increasing knowledge of the diverse physiological functions of glial cells, their impact on these diseases has become more evident. Thus, many conditions appear to have more complex origins than initially thought. Since neurological pathologies are often sporadic with unknown etiology, animal models are difficult to create and might only reflect a small portion of patients in which a mutation in a gene has been identified. Therefore, reliable in vitro systems to studying these disorders are urgently needed. They might be a pre-requisite for improving our understanding of the disease mechanisms as well as for the development of potential new therapies. In this review, we will briefly summarize the function of different glial cell types in the healthy central nervous system (CNS) and outline their implication in the development or progression of neurological conditions. We will then describe different types of culture systems to model non-cell autonomous interactions in vitro and evaluate advantages and disadvantages. This article is part of a Special Issue entitled SI: Exploiting human neurons. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Haptic, Virtual Interaction and Motor Imagery: Entertainment Tools and Psychophysiological Testing

    Directory of Open Access Journals (Sweden)

    Sara Invitto

    2016-03-01

    Full Text Available In this work, the perception of affordances was analysed in terms of cognitive neuroscience during an interactive experience in a virtual reality environment. In particular, we chose a virtual reality scenario based on the Leap Motion controller: this sensor device captures the movements of the user’s hand and fingers, which are reproduced on a computer screen by the proper software applications. For our experiment, we employed a sample of 10 subjects matched by age and sex and chosen among university students. The subjects took part in motor imagery training and immersive affordance condition (a virtual training with Leap Motion and a haptic training with real objects. After each training sessions the subject performed a recognition task, in order to investigate event-related potential (ERP components. The results revealed significant differences in the attentional components during the Leap Motion training. During Leap Motion session, latencies increased in the occipital lobes, which are entrusted to visual sensory; in contrast, latencies decreased in the frontal lobe, where the brain is mainly activated for attention and action planning.

  16. StudTest – A Platform Supporting Complex and Interactive Knowledge Assessment

    Directory of Open Access Journals (Sweden)

    Vlado Glavinić

    2008-12-01

    Full Text Available This paper describes the model and prototype implementation of a knowledge assessment framework based on problem management components. In order to support student testing with complex problem types and enable usage of rich graphical user interfaces for solution entry, we have developed an e-examination model in which the core concept is a component that can generate complex questions and evaluate students' solutions with additional explanation generation, which we named prlet. The respective system implementation is described, which can operate under heavy loads.

  17. Propulsion and airframe aerodynamic interactions of supersonic V/STOL configurations. Volume 2: Wind tunnel test force and moment data report

    Science.gov (United States)

    Zilz, D. E.

    1985-01-01

    A wind tunnel model of a supersonic V/STOL fighter configuration has been tested to measure the aerodynamic interaction effects which can result from geometrically close-coupled propulsion system/airframe components. The approach was to configure the model to represent two different test techniques. One was a conventional test technique composed of two test modes. In the Flow-Through mode, absolute configuration aerodynamics are measured, including inlet/airframe interactions. In the Jet-Effects mode, incremental nozzle/airframe interactions are measured. The other test technique is a propulsion simulator approach, where a sub-scale, externally powered engine is mounted in the model. This allows proper measurement of inlet/airframe and nozzle/airframe interactions simultaneously. This is Volume 2 of 2: Wind Tunnel Test Force and Moment Data Report.

  18. Hemoglobin interactions with αB crystallin: a direct test of sensitivity to protein instability.

    Directory of Open Access Journals (Sweden)

    Tyler J W Clark

    Full Text Available As a small stress response protein, human αB crystallin, detects protein destabilization that can alter structure and function to cause self assembly of fibrils or aggregates in diseases of aging. The sensitivity of αB crystallin to protein instability was evaluated using wild-type hemoglobin (HbA and hemoglobin S (HbS, the glutamate-6-valine mutant that forms elongated, filamentous aggregates in sickling red blood cells. The progressive thermal unfolding and aggregation of HbA and HbS in solution at 37°C, 50°C and 55°C was measured as increased light scattering. UV circular dichroism (UVCD was used to evaluate conformational changes in HbA and HbS with time at the selected temperatures. The changes in interactions between αB crystallin and HbA or HbS with temperature were analyzed using differential centrifugation and SDS PAGE at 37°C, 50°C and 55°C. After only 5 minutes at the selected temperatures, differences in the aggregation or conformation of HbA and HbS were not observed, but αB crystallin bound approximately 6% and 25% more HbS than HbA at 37°C, and 50°C respectively. The results confirmed (a the remarkable sensitivity of αB crystallin to structural instabilities at the very earliest stages of thermal unfolding and (b an ability to distinguish the self assembling mutant form of HbS from the wild type HbA in solution.

  19. Fatigue crack growth behaviour of 21/4Cr1Mo steel tube at elevated temperature

    International Nuclear Information System (INIS)

    Bulloch, J.H.; Buchanan, L.W.

    1987-01-01

    The fatigue crack growth characteristics of 21/4Cr1Mo steel tube have been examined at 588 0 C over the frequency range 0.02-20 Hz and dwell time range 10-960 min. All tests were conducted under load control in laboratory air at an R-ratio of 0.5. The elevated temperature fatigue crack growth characteristics were adequately described in terms of the stress intensity range ΔKAPPA. The continuous cyclic test data exhibited a significant effect of frequency that agreed well with predicted effects using a simple mathematical model of the high temperature fatigue process. With the dwell time range of 10-100 min there was a significant dwell time effect on the critical ΔKAPPA level for creep-fatigue interactive growth. At dwell times > 100 min the dwell time effect saturates. When creep-fatigue interactive growth occurs, growth rates reside above the maximum for continuum-controlled fatigue crack growth, and exhibit a da/dN varies as ΔKAPPA 10 dependence; failure is then intergranular in nature. (author)

  20. Waste Isolation Pilot Plant Materials Interface Interactions Test: Papers presented at the Commission of European Communities workshop on in situ testing of radioactive waste forms and engineered barriers

    International Nuclear Information System (INIS)

    Molecke, M.A.; Sorensen, N.R.

    1993-08-01

    The three papers in this report were presented at the second international workshop to feature the Waste Isolation Pilot Plant (WIPP) Materials Interface Interactions Test (MIIT). This Workshop on In Situ Tests on Radioactive Waste Forms and Engineered Barriers was held in Corsendonk, Belgium, on October 13--16, 1992, and was sponsored by the Commission of the European Communities (CEC). The Studiecentrum voor Kernenergie/Centre D'Energie Nucleaire (SCK/CEN, Belgium), and the US Department of Energy (via Savannah River) also cosponsored this workshop. Workshop participants from Belgium, France, Germany, Sweden, and the United States gathered to discuss the status, results and overviews of the MIIT program. Nine of the twenty-five total workshop papers were presented on the status and results from the WIPP MIIT program after the five-year in situ conclusion of the program. The total number of published MIIT papers is now up to almost forty. Posttest laboratory analyses are still in progress at multiple participating laboratories. The first MIIT paper in this document, by Wicks and Molecke, provides an overview of the entire test program and focuses on the waste form samples. The second paper, by Molecke and Wicks, concentrates on technical details and repository relevant observations on the in situ conduct, sampling, and termination operations of the MIIT. The third paper, by Sorensen and Molecke, presents and summarizes the available laboratory, posttest corrosion data and results for all of the candidate waste container or overpack metal specimens included in the MIIT program

  1. Phonology-morphology interaction: Acquisition of Danish noun plurals as a test case

    DEFF Research Database (Denmark)

    Kjærbæk, Laila; Basbøll, Hans

    2010-01-01

    Phonetic and phonological structure has impact on the acquisition of morphology. Departing from our different types of empirical data, we shall test four specific hypotheses on this impact in Danish, all relying on the principle that opacity delays acquisition: 1) The two overt native plural...... suffixes in Danish contribute to an opaque syllable structure with few and vague cues for identifying the suffix boundaries, thus plural acquisition in Danish should be late. 2) If the plural suffix is subject to dropping, there is less transparency. Since e-schwa, but not a-schwa, often is reduced...... Acquisition in Normal and Hearing Impaired Populations". In E. Schmidt, U. Mikkelsen, I. Post, J. B. Simonsen & K. Fruensgaard (eds.), Brain, Hearing and Learning. 20th Danavox Symposium 2003: 165-190. Bleses, D., Vach, W., Wehberg, S., Kristensen, K. F. & Madsen, T. O. (2007). Tidlig kommunikativ udvikling...

  2. Interactive ultrasonic field simulations for complex non-destructive testing configurations

    International Nuclear Information System (INIS)

    Bhatia, Navnina

    2016-01-01

    Cone tomography is a well established inspection technique for industrial inspection purposes. The generation of scattering noise is inherent to the physical phenomena involved, and occurs both inside the material and the detector. This leads to the apparition of various blurring effects in 2D projections and to reconstruction errors when this effect is not properly taken into account. This works proposes an evolution of the scattering kernel superposition method, aiming at correcting these scattering effect directly in the 2D projections, before the reconstruction process. It consists in fitting analytical kernels that are used to generate realistic scattering contributions, which are in turn subtracted from the 2D projections. The proposed method has been tested using experimental data in cases involving complex materials and different levels of energy. Finally, a joint use of simulated and experimental data is described in the last chapter, in order to enhance the scattering kernels estimation. (author) [fr

  3. Lab-scale impact test to investigate the pipe-soil interaction and comparative study to evaluate structural responses

    Directory of Open Access Journals (Sweden)

    Dong-Man Ryu

    2015-07-01

    Full Text Available This study examined the dynamic response of a subsea pipeline under an impact load to determine the effect of the seabed soil. A laboratory-scale soil-based pipeline impact test was carried out to investigate the pipeline deformation/strain as well as the interaction with the soil-pipeline. In addition, an impact test was simulated using the finite element technique, and the calculated strain was compared with the experimental results. During the simulation, the pipeline was described based on an elasto-plastic analysis, and the soil was modeled using the Mohr-Coulomb fail-ure criterion. The results obtained were compared with ASME D31.8, and the differences between the analysis results and the rules were specifically investigated. Modified ASME formulae were proposed to calculate the precise structural behavior of a subsea pipeline under an impact load when considering sand- and clay-based seabed soils.

  4. FARO test L-14 on fuel coolant interaction and quenching. Comparison report, volume 1 + 2, analysis of the results

    International Nuclear Information System (INIS)

    Annunziato, A.; Addabbo, C.; Yerkess, A.; Silverii, R.; Brewka, W.; Leva, G.

    1997-01-01

    This report provides a comparative analysis of the results from the ISP-39 exercise promoted by OECD-CSNI in the frame of the NEA activities. ISP-39 has been conceived to benchmark the predictive capabilities of computer codes used in the evaluation of fuel-coolant interaction (FCI) and quenching phenomenologies of relevance in water cooled reactors severe accidents safety analysis. The ISP-39 reference case is FARO test L-14, a non-energetic FCI test performed under realistic melt composition and prototypical accident conditions in the FARO experimental installation (Ispra, Italy). Thirteen research organizations from ten countries participated in the exercise submitting 15 prediction calculations with 8 different codes or code versions (COMETA, MC3D, IVA, IFCI, JASMINE, TEXAS, THIRMAL, VAPEX). ISP-39 was conducted as an open exercise. Conclusions are given concerning code capabilities, users effect and sensitivity analyses, numerical accuracy quantification of the predictions, code improvements, general considerations

  5. A Cochlear Implant Performance Prognostic Test Based on Electrical Field Interactions Evaluated by eABR (Electrical Auditory Brainstem Responses.

    Directory of Open Access Journals (Sweden)

    Nicolas Guevara

    Full Text Available Cochlear implants (CIs are neural prostheses that have been used routinely in the clinic over the past 25 years. They allow children who were born profoundly deaf, as well as adults affected by hearing loss for whom conventional hearing aids are insufficient, to attain a functional level of hearing. The "modern" CI (i.e., a multi-electrode implant using sequential coding strategies has yielded good speech comprehension outcomes (recognition level for monosyllabic words about 50% to 60%, and sentence comprehension close to 90%. These good average results however hide a very important interindividual variability as scores in a given patients' population often vary from 5 to 95% in comparable testing conditions. Our aim was to develop a prognostic model for patients with unilateral CI. A novel method of objectively measuring electrical and neuronal interactions using electrical auditory brainstem responses (eABRs is proposed.The method consists of two measurements: 1 eABR measurements with stimulation by a single electrode at 70% of the dynamic range (four electrodes distributed within the cochlea were tested, followed by a summation of these four eABRs; 2 Measurement of a single eABR with stimulation from all four electrodes at 70% of the dynamic range. A comparison of the eABRs obtained by these two measurements, defined as the monaural interaction component (MIC, indicated electrical and neural interactions between the stimulation channels. Speech recognition performance without lip reading was measured for each patient using a logatome test (64 "vowel-consonant-vowel"; VCV; by forced choice of 1 out of 16. eABRs were measured in 16 CI patients (CIs with 20 electrodes, Digisonic SP; Oticon Medical ®, Vallauris, France. Significant correlations were found between speech recognition performance and the ratio of the amplitude of the V wave of the eABRs obtained with the two measurements (Pearson's linear regression model, parametric correlation: r

  6. Testing the Standard Model for the electroweak interactions of the heavy quarks

    International Nuclear Information System (INIS)

    Perret, Pascal

    2002-01-01

    The standard model was a solid theoretical construction. It faced successfully all the tests done at LEP between 1989 and 2000 within 90 GeV to 209 GeV range. The thesis describes the precision measurements of the physical parameters in the heavy quark sector and the tests of the electroweak standard model. The work consists in five parts. The first part is dedicated to some theoretical preliminaries. The electroweak Standard Model is briefly reviewed as well as the necessary elements of the study of heavy flavors. Testing the predictions of the Standard Model and Quantum Chromodynamics requires a comprehensive understanding of heavy quarks. In the second part the LEP accelerator and the ALEPH detector are described as well as the lepton identification within ALEPH, particularly of the electrons. The data acquired in the first LEP phase the interest was allowed investigating the properties of b and c heavy quarks, essential in testing the Standard Model. The studies on b quarks were of most interest because these quarks were more easily to be evidenced experimentally, while the insights on Standard Model are more significant. This quark is heavier (m b = 4 to 4.4 GeV/c 2 ), has a longer lifetime (τ b = 1.564 ± 0.014 ps) and presents the most important semileptonic branching ratios (B(b → l) ∼ 11% ). The principal tools used in their studies were the leptons issued from their decays. In more than 80% of the Z 0 → bb-bar events there is at least one lepton (an electron or muon) issued from the direct or secondary decay of a beauty hadron. In the case of charm, 40% of events produce at least one lepton. By taking into account the lepton identification accuracy and the fact that a number of kinetic cuts should be applied to get rid of the too high a background noise (p > 2 or 3 GeV/c), 50% of the leptons are lost. The fraction is however high and additional criteria should be applied in order to increase the amount of interesting events. Hence, a vertex

  7. Interaction between basigin and monocarboxylate transporter 2 in the mouse testes and spermatozoa

    Directory of Open Access Journals (Sweden)

    Cheng Chen

    2016-01-01

    Full Text Available Basigin is a member of the immunoglobulin superfamily and plays various important roles in biological events including spermatogenesis. To examine the basigin molecular variants during spermatogenesis and sperm maturation in the mouse, immunoprecipitated basigin samples from testis and epididymal spermatozoa were analyzed by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS. The results demonstrated that basigin molecules from the testis and spermatozoa were separable into two major bands and that the differences in the molecular sizes were possibly because of an endoproteolytic cleavage. Since basigin is known to be a chaperone for the monocarboxylate transporter 1 (MCT1, the localization of basigin, MCT1 and MCT2 was examined during postnatal testicular development. Immunohistochemical studies showed different expression patterns of MCT1 and MCT2. MCT1 was localized on the surface of spermatogonia, spermatocytes, and spermatids. In contrast, MCT2 appeared on the principal piece of spermatozoa in the testis, where basigin was also observed. In mature epididymal spermatozoa, MCT2 was located on the midpiece, where basigin co-localized with MCT2 but not with MCT1. Furthermore, MCT2 was immunoprecipitated with basigin in mouse testes and sperm. These results suggest that basigin has a functional role as a binding partner with MCT2 in testicular and epididymal spermatozoa.

  8. Electrophoretic characterization of protein interactions suggesting limited feasibility of accelerated shelf-life testing of ultra-high temperature milk.

    Science.gov (United States)

    Grewal, Manpreet Kaur; Chandrapala, Jayani; Donkor, Osaana; Apostolopoulos, Vasso; Vasiljevic, Todor

    2017-01-01

    Accelerated shelf-life testing is applied to a variety of products to estimate keeping quality over a short period of time. The industry has not been successful in applying this approach to ultra-high temperature (UHT) milk because of chemical and physical changes in the milk proteins that take place during processing and storage. We investigated these protein changes, applying accelerated shelf-life principles to UHT milk samples with different fat levels and using native- and sodium dodecyl sulfate-PAGE. Samples of UHT skim and whole milk were stored at 20, 30, 40, and 50°C for 28d. Irrespective of fat content, UHT treatment had a similar effect on the electrophoretic patterns of milk proteins. At the start of testing, proteins were bonded mainly through disulfide and noncovalent interactions. However, storage at and above 30°C enhanced protein aggregation via covalent interactions. The extent of aggregation appeared to be influenced by fat content; whole milk contained more fat than skim milk, implying aggregation via melted or oxidized fat, or both. Based on reduction in loss in absolute quantity of individual proteins, covalent crosslinking in whole milk was facilitated mainly by products of lipid oxidation and increased access to caseins for crosslinking reactions. Maillard and dehydroalanine products were the main contributors involved in protein changes in skim milk. Protein crosslinking appeared to follow a different pathway at higher temperatures (≥40°C) than at lower temperatures, making it very difficult to extrapolate these changes to protein interactions at lower temperatures. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. Testing the Impact of Child Characteristics × Instruction Interactions on Third Graders’ Reading Comprehension by Differentiating Literacy Instruction

    Science.gov (United States)

    Connor, Carol McDonald; Morrison, Fredrick J.; Fishman, Barry; Giuliani, Sarah; Luck, Melissa; Underwood, Phyllis S.; Bayraktar, Aysegul; Crowe, Elizabeth C.; Schatschneider, Christopher

    2016-01-01

    There is accumulating correlational evidence that the effect of specific types of reading instruction depends on children’s initial language and literacy skills, called child characteristics × instruction (C×I) interactions. There is, however, no experimental evidence beyond first grade. This randomized control study examined whether C×I interactions might present an underlying and predictable mechanism for explaining individual differences in how students respond to third-grade classroom literacy instruction. To this end, we designed and tested an instructional intervention (Individualizing Student Instruction [ISI]). Teachers (n = 33) and their students (n = 448) were randomly assigned to the ISI intervention or a vocabulary intervention, which was not individualized. Teachers in both conditions received professional development. Videotaped classroom observations conducted in the fall, winter, and spring documented the instruction that each student in the classroom received. Teachers in the ISI group were more likely to provide differentiated literacy instruction that considered C×I interactions than were the teachers in the vocabulary group. Students in the ISI intervention made greater gains on a standardized assessment of reading comprehension than did students in the vocabulary intervention. Results indicate that C×I interactions likely contribute to students’ varying response to literacy instruction with regard to their reading comprehension achievement and that the association between students’ profile of language and literacy skills and recommended instruction is nonlinear and dependent on a number of factors. Hence, dynamic and complex theories about classroom instruction and environment impacts on student learning appear to be warranted and should inform more effective literacy instruction in third grade. PMID:27867226

  10. Testing the Impact of Child Characteristics × Instruction Interactions on Third Graders' Reading Comprehension by Differentiating Literacy Instruction.

    Science.gov (United States)

    Connor, Carol McDonald; Morrison, Fredrick J; Fishman, Barry; Giuliani, Sarah; Luck, Melissa; Underwood, Phyllis S; Bayraktar, Aysegul; Crowe, Elizabeth C; Schatschneider, Christopher

    2011-01-01

    There is accumulating correlational evidence that the effect of specific types of reading instruction depends on children's initial language and literacy skills, called child characteristics × instruction (C×I) interactions. There is, however, no experimental evidence beyond first grade. This randomized control study examined whether C×I interactions might present an underlying and predictable mechanism for explaining individual differences in how students respond to third-grade classroom literacy instruction. To this end, we designed and tested an instructional intervention (Individualizing Student Instruction [ISI]). Teachers ( n = 33) and their students ( n = 448) were randomly assigned to the ISI intervention or a vocabulary intervention, which was not individualized. Teachers in both conditions received professional development. Videotaped classroom observations conducted in the fall, winter, and spring documented the instruction that each student in the classroom received. Teachers in the ISI group were more likely to provide differentiated literacy instruction that considered C×I interactions than were the teachers in the vocabulary group. Students in the ISI intervention made greater gains on a standardized assessment of reading comprehension than did students in the vocabulary intervention. Results indicate that C×I interactions likely contribute to students' varying response to literacy instruction with regard to their reading comprehension achievement and that the association between students' profile of language and literacy skills and recommended instruction is nonlinear and dependent on a number of factors. Hence, dynamic and complex theories about classroom instruction and environment impacts on student learning appear to be warranted and should inform more effective literacy instruction in third grade.

  11. Education did not interact with major depression on performance of memory tests in acute southern Brazilian in patients

    Science.gov (United States)

    Fleck, Analuiza Camozzato; de Almeida, Marcelo Pio; Delgado, Vera; Chaves, Marcia Lorena Fagundes

    2007-01-01

    The relationship of cognitive function to depression in older adults has become a topic of extensive clinical interest and research. Objective To analyze association between cognitive/memory performance,Major Depression, and education in 206 inpatients from the Psychiatry and Internal Medicine Departments. Methods Patients were evaluated by the Mini Mental State Examination, a battery of memory tests, and the Montgomery-Åsberg Depression Rating Scale. Depression patients comprised 45 severe and 42 mild/moderate, according to the Montgomery-Asberg scale. The effect of psychoactive drugs was recorded (30% drug-free). Education was measured in years. Cognitive/memory tests assessed five domains: general mental functioning, attention, sustained attention/working memory, learning memory (verbal), and remote memory. An index for memory impairment was created (positivity: 50% of tests below cutoff). Results The chief effect on worse performance was Major Depression for the domains (age and education adjusted) of attention, learning, remote memory, and general functioning. For the domain “sustained attention and working memory”, only severely depressed patients differed from the medical controls (p=.008). Education showed an independent effect on test performances. No interaction between depression and educational status was observed.We also observed an independent effect of psychoactive drugs on some cognitive/memory domains. Logistic Regression showed Major Depression as the main risk for cognitive impairment. Conclusions These data demonstrated association of Major Depression with impaired cognitive performance independent of educational attainment or psychiatric medications. PMID:29213364

  12. Testing a dynamic-field account of interactions between spatial attention and spatial working memory.

    Science.gov (United States)

    Johnson, Jeffrey S; Spencer, John P

    2016-05-01

    Studies examining the relationship between spatial attention and spatial working memory (SWM) have shown that discrimination responses are faster for targets appearing at locations that are being maintained in SWM, and that location memory is impaired when attention is withdrawn during the delay. These observations support the proposal that sustained attention is required for successful retention in SWM: If attention is withdrawn, memory representations are likely to fail, increasing errors. In the present study, this proposal was reexamined in light of a neural-process model of SWM. On the basis of the model's functioning, we propose an alternative explanation for the observed decline in SWM performance when a secondary task is performed during retention: SWM representations drift systematically toward the location of targets appearing during the delay. To test this explanation, participants completed a color discrimination task during the delay interval of a spatial-recall task. In the critical shifting-attention condition, the color stimulus could appear either toward or away from the midline reference axis, relative to the memorized location. We hypothesized that if shifting attention during the delay leads to the failure of SWM representations, there should be an increase in the variance of recall errors, but no change in directional errors, regardless of the direction of the shift. Conversely, if shifting attention induces drift of SWM representations-as predicted by the model-systematic changes in the patterns of spatial-recall errors should occur that would depend on the direction of the shift. The results were consistent with the latter possibility-recall errors were biased toward the locations of discrimination targets appearing during the delay.

  13. Testing a Dynamic Field Account of Interactions between Spatial Attention and Spatial Working Memory

    Science.gov (United States)

    Johnson, Jeffrey S.; Spencer, John P.

    2016-01-01

    Studies examining the relationship between spatial attention and spatial working memory (SWM) have shown that discrimination responses are faster for targets appearing at locations that are being maintained in SWM, and that location memory is impaired when attention is withdrawn during the delay. These observations support the proposal that sustained attention is required for successful retention in SWM: if attention is withdrawn, memory representations are likely to fail, increasing errors. In the present study, this proposal is reexamined in light of a neural process model of SWM. On the basis of the model's functioning, we propose an alternative explanation for the observed decline in SWM performance when a secondary task is performed during retention: SWM representations drift systematically toward the location of targets appearing during the delay. To test this explanation, participants completed a color-discrimination task during the delay interval of a spatial recall task. In the critical shifting attention condition, the color stimulus could appear either toward or away from the memorized location relative to a midline reference axis. We hypothesized that if shifting attention during the delay leads to the failure of SWM representations, there should be an increase in the variance of recall errors but no change in directional error, regardless of the direction of the shift. Conversely, if shifting attention induces drift of SWM representations—as predicted by the model—there should be systematic changes in the pattern of spatial recall errors depending on the direction of the shift. Results were consistent with the latter possibility—recall errors were biased toward the location of discrimination targets appearing during the delay. PMID:26810574

  14. Stirling engine---available tools for long-life assessment

    International Nuclear Information System (INIS)

    Halford, G.R.; Bartolotta, P.A.

    1991-01-01

    A review is presented of the durability approaches applicable to long-time life assessment of Stirling engine hot-section components. The crucial elements are: (i) experimental techniques for generating long-time materials property data (both monotonic and cyclic flow and failure properties), (ii) analytic representations of slow strain rate material stress-strain response characteristics (monotonic and cyclic constitutive relations) at high temperatures and low stresses and strains, (iii) analytic creep-fatigue-environmental interaction life prediction methods applicable to long lifetimes at high temperatures and small stresses and strains, and (iv) experimental verification of life predictions. Long-lifetime design criteria for materials of interest are woefully lacking. Designing against failures due to creep, creep-rupture, fatigue, environmental attack, and creep-fatigue-environmental interaction will require considerable extrapolation. Viscoplastic constitutive models and time-temperature parameters will have to be calibrated for the hot-section materials of interest. Analysis combined with limited verification testing in a short-time regime will be required to build confidence in long-term durability models. A strong need exists for improved long-lifetime durability models

  15. Magnetic Fusion Energy Plasma Interactive and High Heat Flux Components: Volume 5, Technical assessment of critical issues in the steady state operation of fusion confinement devices

    International Nuclear Information System (INIS)

    1988-01-01

    Critical issues for the steady state operation of plasma confinement devices exist in both the physics and technology fields of fusion research. Due to the wide range and number of these issues, this technical assessment has focused on the crucial issues associated with the plasma physics and the plasma interactive components. The document provides information on the problem areas that affect the design and operation of a steady state ETR or ITER type confinement device. It discusses both tokamaks and alternative concepts, and provides a survey of existing and planned confinement machines and laboratory facilities that can address the identified issues. A universal definition of steady state operation is difficult to obtain. From a physics point of view, steady state is generally achieved when the time derivatives approach zero and the operation time greatly exceeds the characteristic time constants of the device. Steady state operation for materials depends on whether thermal stress, creep, fatigue, radiation damage, or power removal are being discussed. For erosion issues, the fluence and availability of the machine for continuous operation are important, assuming that transient events such as disruptions do not limit the component lifetimes. The panel suggests, in general terms, that steady state requires plasma operation from 100 to 1000 seconds and an availability of more than a few percent, which is similar to the expectations for an ETR type device. The assessment of critical issues for steady state operation is divided into four sections: physics issues; technology issues; issues in alternative concepts; and devices and laboratory facilities that can address these problems

  16. Magnetic Fusion Energy Plasma Interactive and High Heat Flux Components: Volume 5, Technical assessment of critical issues in the steady state operation of fusion confinement devices

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    Critical issues for the steady state operation of plasma confinement devices exist in both the physics and technology fields of fusion research. Due to the wide range and number of these issues, this technical assessment has focused on the crucial issues associated with the plasma physics and the plasma interactive components. The document provides information on the problem areas that affect the design and operation of a steady state ETR or ITER type confinement device. It discusses both tokamaks and alternative concepts, and provides a survey of existing and planned confinement machines and laboratory facilities that can address the identified issues. A universal definition of steady state operation is difficult to obtain. From a physics point of view, steady state is generally achieved when the time derivatives approach zero and the operation time greatly exceeds the characteristic time constants of the device. Steady state operation for materials depends on whether thermal stress, creep, fatigue, radiation damage, or power removal are being discussed. For erosion issues, the fluence and availability of the machine for continuous operation are important, assuming that transient events such as disruptions do not limit the component lifetimes. The panel suggests, in general terms, that steady state requires plasma operation from 100 to 1000 seconds and an availability of more than a few percent, which is similar to the expectations for an ETR type device. The assessment of critical issues for steady state operation is divided into four sections: physics issues; technology issues; issues in alternative concepts; and devices and laboratory facilities that can address these problems.

  17. Low cycle fatigue of PM/HIP astroloy

    Energy Technology Data Exchange (ETDEWEB)

    Choe, S.J.; Stoloff, N.S.; Duquette, D.J. (Rensselaer Polytechnic Institute, Troy, NY (USA))

    Low cycle fatigue and creep-fatigue-environment interactions of PM/HIP Astrology were studied at 650 C and 725 C. Total strain range was varied from 1.5% to 2.7% at a frequency of 0.3Hz. Creep-fatigue tests were performed with 2 min. or 5 min. tensile hold times. All tests were run in high purity argon in an attempt to minimize environmental effects. Employing a tensile hold was more damaging than raising temperature by 75 C. Slopes of Coffin-Manson plots were nearly independent of temperature and hold time. Raising temperature from 650 C to 725 C did not change the transgranular (TG) crack propagation mode, whereas employing hold times caused TG+IG propagation. All samples displayed multiple fracture origins associated with inclusions located at the specimen surface; pre-existing pores did not affect fatigue crack initiation. Examination of secondary cracks showed no apparent creep damage. Oxidation in high purity argon appeared to be the major factor in LCF life degradation due to hold times.

  18. Genotype-by-Environment Interaction and Testing Environments for Plantain and Banana (Musa spp. L. Breeding in West Africa

    Directory of Open Access Journals (Sweden)

    Ortiz, R.

    1999-01-01

    Full Text Available With reduced budgets allocated for international agricultural research, site rationalisation had become an important issue to consider when carrying out multilocational testing of promising selections. The aim of this paper was to determine the importance of the genotype-by-environment interaction in multilocational trials of plantains and bananas (Musa spp. L. in selected sites of West Africa comprising the humid forest and the forest-savanna transition zones. A sample of plantain-banana hybrids, plantain landraces, exotic banana cultivars and diploid parental banana accessions were evaluated in three locations : Mbalmayo and Onne (humid forest and Ibadan (forest-savanna transition. The experimental results of our research suggested that multilocational testing is more profitable than single site evaluation over several years in the Musa breeding station. Furthermore, based on correlated responses across environments for yield potential, we suggest that one of the selection sites in the humid forest (i. e., Mbalmayo be dropped since selections in one site (Onne may be well adapted to the other location in the same agroecozone. Conversely, the relatively poor performance of most genotypes in dry environments (e. g. Ibadan reinforces the importance of early testing across a wide range of environments. In this way selections with broad or specific adaptation may be identified for further release to targeted farmers.

  19. Synergistic interactions between the antinociceptive effect of Rhodiola rosea extract and B vitamins in the mouse formalin test.

    Science.gov (United States)

    Montiel-Ruiz, Rosa Mariana; González-Trujano, María Eva; Déciga-Campos, Myrna

    2013-11-15

    In this study, the pharmacological interactions between a Rhodiola rosea ethanol extract and B-vitamins such as thiamine (B1), riboflavine (B2), pyridoxine (B6), cyanocobalamin (B12) and a mixture of vitamins B1+B6+B12 was investigated in the mouse formalin test. Individual dose response curves of the Rhodiola rosea ethanol extract, as well as B-vitamins alone or in a mixture were evaluated in mice in which nociception was induced with 2% formalin intraplantarly. The antinociceptive mechanisms of the Rhodiola rosea were investigated by exploring the role of the opioid and serotonin receptors and the nitric oxide pathway. Isobolographic analysis was used to evaluate the pharmacological interactions between the Rhodiola rosea ethanol extract and each B-vitamin individually or the mixture of vitamins B1+B6+B12 by using the ED30 and a fixed 1:1 ratio combination. Administration of the Rhodiola rosea extract alone or in combination with all of the vitamins produced a significant and dose-dependent antinociceptive response. The antinociceptive effect of the Rhodiola rosea extract (ED50=81 mg/kg, p.o.) was significant and reverted in the presence of antagonists of the 5-HT1A, GABA/BDZs and opioid receptors and by blocking mediators of the nitric oxide/cGMP/K(+) channels pathway. Isobolograms demonstrate that all of the combinations investigated in this study produced a synergistic interaction experimental ED30 values were significantly smaller than those calculated theoretically. These results provide evidence that a Rhodiola rosea ethanol extract in combination with B-vitamins produces a significant diminution in the nociceptive response in a synergistic manner, which is controlled by various mechanisms. These findings could aid in the design of clinical studies and suggest that these combinations could be applied for pain therapy. Copyright © 2013 Elsevier GmbH. All rights reserved.

  20. Synergistic interaction between mazindol, an anorectic drug, and swim-stress on analgesic responses in the formalin test in mice.

    Science.gov (United States)

    Vendruscolo, Leandro Franco; Takahashi, Reinaldo Naoto

    2004-01-23

    The present study examined the interaction between mazindol (MZ), an anorectic drug extensively used in Brazil and opioid/non-opioid endogenous analgesic systems activated by swim-stress. Further, the role of opioid, dopamine and N-methyl-D-aspartate (NMDA) receptors in mediating the analgesic effect was evaluated. The stress-induced analgesia of a 3-min swimming at 32 degrees C (opioid/non-opioid) and 20 degrees C (non-opioid) were assessed using the formalin test. Male Swiss mice were intraperitoneally injected with naloxone (1.0 mg/kg), sulpiride (3.0 mg/kg), MK-801 (0.075 mg/kg) or saline/vehicle 15 min prior, and with MZ (0.5 mg/kg) or saline/vehicle 5 min prior to swimming. The dose of MZ (0.5 mg/kg) did not cause analgesic effect, however, the association of MZ and swim-stress at both temperatures displayed synergistic interaction on analgesia that was blocked by sulpiride and MK-801 but not by naloxone. The present results suggest that MZ and swim-stress acted synergistically on analgesic responses, involving mainly the non-opioid component and possibly mediated by dopamine D2 receptors and NMDA receptors.

  1. Non-Reactor testing stands for investigation of interaction of the fuel and constructive materials with the coolant

    International Nuclear Information System (INIS)

    Vasil'ev, Yu.S.; Zuev, V.A.; Ivanov, V.Ya.; Ivonin, V.V.; Pivovarov, O.S.; Soloviev, V.M.

    1993-01-01

    In 1991 in the United Expedition of Scientific and Industrial Corp. Luch the non-reactor experiments were beginning. The appearances accompanied by water cooling reactor heavy accident were studied. There are 'Ruchej', 'LAVA', 'SLAVA' experimental facilities working out for such purposes. The 'Ruchej' facility is intended for conducting of the investigation of behavior of water cooling reactor core constructive elements in the high temperature gas-steam media. There were 27 testing start-up of 'Ruchej' facility and 70 fuel elements shells samples and 2 models fuel elements. 'LAVA' facility is intended to study the processes of the interaction of the melting composition of WWER-1000 reactor core with water. The 'SLAVA' facility is destined for study of corium jet characteristics and the processes of interaction of corium with WWER-1000 reactor constructive materials. The corium generation is realized in the electric melting furnaces (EPP-1, EPP-2) and both of them could be using for the 'LAVA' facility and the 'SLAVA' facility. The expenses, temperature, pressure of the water in the facility's cooling highway, pressure of gas within device, temperature of the corium or its imitator, geometrical parameters of stream' temperature of construct device's elements, electric parameters (voltage, current) has being registered

  2. An interactional test of the reformulated helplessness theory of depression in women receiving clinical treatment for eating disorders.

    Science.gov (United States)

    Rotenberg, Ken J; Costa, Paula; Trueman, Mark; Lattimore, Paul

    2012-08-01

    The study tested the Reformulated Helplessness model that individuals who show combined internal locus of control, high stability and high globality attributions for negative life events are prone to depression. Thirty-six women (M=29 years-8 months of age) receiving clinical treatment for eating disorders completed: the Attribution Style Questionnaire, the Beck Depression Inventory, and the Stirling Eating Disorder Scales. An HRA yielded a three-way interaction among the attributional dimensions on depressive symptoms. Plotting of the slopes showed that the attribution of negative life events to the combination of internal locus of control, high stability, and a high globality, was associated with the optimal level of depressive symptoms. The findings supported the Reformulated Helplessness as a model of depression. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. [Evaluation of postural characteristics in patients with vertigo by modified clinical test of sensory interaction and balance].

    Science.gov (United States)

    Liu, Bo; Kong, Weijia; Lai, Changqin

    2009-02-01

    To investigate the application of modified clinical test of sensory interaction and balance (mCTSIB) in the patients with vertigo. One hundred and six patients with vertigo (62 cases with peripheral and 44 cases with central vestibular disorder) were taken the mCTSIB of the firm surface and foam surface with eye open and eye closed for 30 seconds respectively. The standing foam surface was to interrupt the somatosensory and closing eyes was to interrupt the visual input in the postural stability. The falling during the test was recorded. The results between the mCTSIB and video nystagmography (VNG) were compared. In vestibular peripheral disorder, the abnormal of mCTSIB was 45.16% (28/62) and agreement to VNG was 67.74% (42/62). In vestibular central disorder, the abnormal of mCTSIB was 27.27% (12/44) and agreement to VNG was 81.82% (36/44). For all these patients with vertigo in this study, the abnormal of mCTSIB was 37.74% (40/106) and agreement to VNG was 73.58% (78/106). Regarding the falling as abnormality, the mCTSIB was not significant different between the vestibular peripheral and central disorders (chi2 = 3.505, P > 0.05). Although the mCTSIB, which was easy to carry out, can not be a method to differentiate the vestibular peripheral and central disorders, it was a suitable to assess the ability of sensory interaction to maintain balance in patients with vertigo.

  4. Test

    DEFF Research Database (Denmark)

    Bendixen, Carsten

    2014-01-01

    Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers.......Bidrag med en kortfattet, introducerende, perspektiverende og begrebsafklarende fremstilling af begrebet test i det pædagogiske univers....

  5. Estimation of crack growth in the creep range during plastic cyclic loading

    International Nuclear Information System (INIS)

    Kullik, M.; Maile, K.

    1990-01-01

    Crack growth investigations were performed on the creep-resistant steel 13 CrMo 4 4 in the fatigue and the creep fatigue regime, especially regarding the influence of creep damage on crack growth. To this effect, 2% creep strain was applied to the material at a temperature of 560deg C. The crack propagation rate was determined as a functionof the specimen shape, temperature, test frequency and hold times. In the case of compact tension (CT-)specimens, creep pretreatment does not affect crack growth. For center-cracked tension (CCT-)specimens, however, the creep pretreatment results in a considerable increase in the crack propagation rate. Hold times of 90 minutes at maximum loading cause an increase in da/dN due to further cavity nucleation. The hold time at which cavity nucleation might occur is evaluated. The dependency on frequency of crack growth may be evaluated by means of a linear superposition of creep and fatigue crack growth. The transition frequency above which pure fatigue crack growth occurs is calculated and the regimes of fatigue, creep and creep-fatigue interaction with environmental influences are characterized. (orig.)

  6. Failure Mechanisms and Damage Model of Ductile Cast Iron Under Low-Cycle Fatigue Conditions

    Science.gov (United States)

    Wu, Xijia; Quan, Guangchun; MacNeil, Ryan; Zhang, Zhong; Sloss, Clayton

    2014-10-01

    Strain-controlled low-cycle fatigue (LCF) tests were conducted on ductile cast iron (DCI) at strain rates of 0.02, 0.002, and 0.0002/s in the temperature range from room temperature to 1073 K (800 °C). A constitutive-damage model was developed within the integrated creep-fatigue theory (ICFT) framework on the premise of strain decomposition into rate-independent plasticity and time-dependent creep. Four major damage mechanisms: (i) plasticity-induced fatigue, (ii) intergranular embrittlement (IE), (iii) creep, and (iv) oxidation were considered in a nonlinear creep-fatigue interaction model which represents the overall damage accumulation process consisting of oxidation-assisted fatigue crack nucleation and propagation in coalescence with internally distributed damage ( e.g., IE and creep), leading to final fracture. The model was found to agree with the experimental observations of the complex DCI-LCF phenomena, for which the linear damage summation rule would fail.

  7. Via-Satellite Trials of W-CDMA Multimedia Broadcasting and Interactive Packet Access: The ESA Advanced Test Bed (ATB)

    Science.gov (United States)

    Barbosa, A.; Buck, M.; Chiassarini, G.; De Gaudenzi, R.; Geracitano, G.; Perez-Carro, A.; Roza, Jose; Vernucci, A.; Widmer, H.

    2003-07-01

    This paper provides an overview on the ESA-funded Advanced S-UMTS Test Bed (ATB) project, intended to define, validate and demonstrate 3G mobile via-satellite services. One of the main project targets is to develop a set of technical solutions for the interactive packet-access aiming to efficiently exploit the radio resources, as well as for the multicast- mode, so opening the road to the deployment of those multimedia broadcasting services which are predicted to represent the most important Satellite-UMTS (S-UMTS) market share. After illustrating the main aims of ATB, the paper presents the architecture of the real-time end-to-end Test Bed which was developed to support both laboratory and over-the-air trials, and provides a brief description of its main constituting elements. Finally, the architecture of the overall via-satellite demonstrator is addressed. Presently, the ATB hardware is in final integration stage at Space Engineering, and via-satellite trials are planned to take place by the second half of year 2003.

  8. Influence of a long-term powdered diet on the social interaction test and dopaminergic systems in mice.

    Science.gov (United States)

    Niijima-Yaoita, Fukie; Tsuchiya, Masahiro; Saito, Hiroko; Nagasawa, Yuka; Murai, Shigeo; Arai, Yuichiro; Nakagawasai, Osamu; Nemoto, Wataru; Tadano, Takeshi; Tan-No, Koichi

    2013-10-01

    It is well known that the characteristics of mastication are important for the maintenance of our physical well-being. In this study, to assess the importance of the effects of food hardness during mastication, we investigated whether a long-term powdered diet might cause changes in emotional behavior tests, including spontaneous locomotor activity and social interaction (SI) tests, and the dopaminergic system of the frontal cortex and hippocampus in mice. Mice fed a powdered diet for 17 weeks from weaning were compared with mice fed a standard diet (control). The dopamine turnover and expression of dopamine receptors mRNA in the frontal cortex were also evaluated. Spontaneous locomotor activity, SI time and dopamine turnover of the frontal cortex were increased in powdered diet-fed mice. On the other hand, the expression of dopamine-4 (D4) receptors mRNA in the frontal cortex was decreased in powdered diet-fed mice. Moreover, we examined the effect of PD168077, a selective D4 agonist, on the increased SI time in powdered diet-fed mice. Treatment with PD168077 decreased the SI time. These results suggest that the masticatory dysfunction induced by long-term powdered diet feeding may cause the increased SI time and the changes in the dopaminergic system, especially dopamine D4 receptor subtype in the frontal cortex. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Sexual selection on plumage and behavior in an avian hybrid zone: experimental tests of male-male interactions.

    Science.gov (United States)

    McDonald, D B; Clay, R P; Brumfield, R T; Braun, M J

    2001-07-01

    In western Panama, an unusual hybrid zone exists between white-collared manakins, Manacus candei, and golden-collared manakins, M. vitellinus. Unidirectional introgression of plumage traits from vitellinus into candei has created a region in which all definitively plumaged males have a collar that is lemon-colored. These males are nearly indistinguishable from white-collared candei genetically and morphometrically, but strongly resemble golden-collared vitellinus due to the introgression of secondary sexual plumage traits, particularly the lemon-colored collar. The introgression could be explained by sexual selection for golden-collared traits or by a series of mechanisms that do not invoke sexual selection (e.g., neutral diffusion, dominant allele). Sexual selection on male-male interactions implies behavioral differences among the plumage forms--specifically that golden- and lemon-collared males should be more aggressive than white-collared males. In contrast, the nonsexual hypotheses predict behavioral similarity between lemon- and white-collared males, based on their nearly identical genetics. We tested the sexual selection hypothesis experimentally, by presenting males with taxidermic mounts of the three forms. As response variables, we monitored vocalizations and attacks on the mounts by replicate subject males. Both golden-collared and lemon-collared males were more likely to attack than were white-collared males, as predicted under sexual selection but not by the nonsexual hypotheses. Lemon-collared males were more vocally reactive than either parental form, contrary to the prediction of the nonsexual hypotheses. Our study demonstrates that sexual selection on male-male interactions may play an important role in the dynamics of character evolution and hybrid zones.

  10. Analysis of the forced vibration test of the Hualien large scale soil-structure interaction model using a flexible volume substructuring method

    International Nuclear Information System (INIS)

    Tang, H.T.; Nakamura, N.

    1995-01-01

    A 1/4-scale cylindrical reactor containment model was constructed in Hualien, Taiwan for foil-structure interaction (SSI) effect evaluation and SSI analysis procedure verification. Forced vibration tests were executed before backfill (FVT-1) and after backfill (FVT-2) to characterize soil-structure system characteristics under low excitations. A number of organizations participated in the pre-test blind prediction and post-test correlation analyses of the forced vibration test using various industry familiar methods. In the current study, correlation analyses were performed using a three-dimensional flexible volume substructuring method. The results are reported and soil property sensitivities are evaluated in the paper. (J.P.N.)

  11. Geographic-didactical games as interactive tools to test and improve student's basic knowledge in Physical Geography

    Science.gov (United States)

    Winkler, S.; Tintrup Gen. Suntrup, A.

    2009-04-01

    Due to an increasing disproportion between experienced teaching staff and student numbers at German universities, the time available for teaching the fundamental basic knowledge in Physical Geography was condensed during the past decade. Unfortunately, this mainly has been achieved at the expense of practical lessons of testing student's knowledge. The recent introduction of the Bachelor/Master degree has not solved this problem, but rather accelerated that tend. The "losers" of this tendency are those students enrolled in trainee teacher studies in Geography. In conjunction with the recent modifications of the study programs putting more focus on applied or specialized fields of Geography and its methodology, the trainee teacher students often express their critics and urgently demand opportunities to improve and test their basic knowledge (because it is especially that knowledge, they need at school and for their traditional examination). As the study program is quite dense, there is no room for special courses or seminars. By contrast, one has to use some free time slots available e.g. in the evenings of the usually quite long German excursions or of weekend seminars. However, after a day in the field or in the classroom, the teacher has to find a method owing enough excitement and clearly visible benefit for the students to achieve sufficient motivation. Interactive geographic-didactical games have been developed exclusively for this purpose and applied at different occasions. Those games had the goal of testing student's basic knowledge in a rather unconventional and "casual" style in order to motivate active participation. Most of the games could be played in small groups of students with the teacher only occasionally being involved as referee. Of course, the games had the general aim of improving the basic knowledge - or at least give the students the possibility to discover their own strength (or weakness) just before it is too late (as it e.g. would be

  12. Behaviour of ODS Steels in Cyclic Loading

    Czech Academy of Sciences Publication Activity Database

    Kuběna, Ivo; Kruml, Tomáš; Polák, Jaroslav

    2016-01-01

    Roč. 69, č. 2 (2016), s. 309-313 ISSN 0972-2815. [International Conference on CREEP, FATIGUE and CREEP-FATIGUE INTERACTION /7./. Kalpakkam, 19.01.2016-22.01.2016] R&D Projects: GA MŠk(CZ) ED1.1.00/02.0068; GA ČR GA15-08826S Institutional support: RVO:68081723 Keywords : ODS steels * low cycle fatigue * small fatigue crack * microstructure Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.533, year: 2016 http://link.springer.com/article/10.1007/s12666-015-0814-3

  13. The effect of combined treatment with risperidone and antidepressants on the MK-801-induced deficits in the social interaction test in rats.

    Science.gov (United States)

    Kamińska, Katarzyna; Rogóż, Zofia

    2015-12-01

    Several clinical reports have suggested that augmentation of atypical antipsychotics' activity by antidepressants may efficiently improve the treatment of negative and some cognitive symptoms of schizophrenia. The aim of the present study was to investigate the effect of antidepressant mirtazapine or escitalopram and risperidone (an atypical antipsychotic), given separately or jointly, on the MK-801-induced deficits in the social interaction test in rats. Antidepressants and risperidone were given 60 and 30 min before the test, respectively. The social interaction of male Wistar rats was measured for 10 min, starting 4 h after MK-801 (0.1 mg/kg) administration. In the social interaction test, MK-801-induced deficits in the parameters studied, i.e. the number of episodes and the time of interactions. Risperidone at a higher dose (0.1 mg/kg) reversed that effect. Co-treatment with an ineffective dose of risperidone (0.01 mg/kg) and mirtazapine (2.5 or 5 mg/kg) or escitalopram only at a dose of 5 mg/kg (but not 2.5 and 10 mg/kg) abolished the deficits evoked by MK-801. The obtained results suggest that especially mirtazapine, and to a smaller degree escitalopram may enhance the antipsychotic-like effect of risperidone in the animal test modeling some negative symptoms of schizophrenia. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  14. A Case-Series Test of the Interactive Two-Step Model of Lexical Access: Predicting Word Repetition from Picture Naming

    Science.gov (United States)

    Dell, Gary S.; Martin, Nadine; Schwartz, Myrna F.

    2007-01-01

    Lexical access in language production, and particularly pathologies of lexical access, are often investigated by examining errors in picture naming and word repetition. In this article, we test a computational approach to lexical access, the two-step interactive model, by examining whether the model can quantitatively predict the repetition-error…

  15. The Other End of the Leash: An Experimental Test to Analyze How Owners Interact with Their Pet Dogs

    OpenAIRE

    Cimarelli, Giulia; Turcsán, Borbála; Range, Friederike; Virányi, Zsófia

    2017-01-01

    It has been suggested that the way in which owners interact with their dogs can largely vary and influence the dog-owner bond, but very few objective studies, so far, have addressed how the owner interacts with the dog. The goal of the present study was to record dog owners' interaction styles by means of objective observation and coding. The experiment included eight standardized situations in which owners of pet dogs were asked to perform specific tasks including both positive (i.e. playing...

  16. An overview of fatigue

    International Nuclear Information System (INIS)

    Mc Evily, A.J.

    1987-01-01

    Four topics are briefly discussed in this paper: fatigue crack initiation and growth in a nickel-base superalloy single crystal, the environment effect on near-threshold fatigue crack growth behaviour, the role of crack closure in load-interaction effects in fatigue crack growth, and the nature of creep-fatigue interactions, if any, during fatigue crack growth. (Author)

  17. Synergistic Interaction between Metformin and Sulfonylureas on Diclofenac-Induced Antinociception Measured Using the Formalin Test in Rats

    Directory of Open Access Journals (Sweden)

    Mario I Ortiz

    2013-01-01

    Full Text Available BACKGROUND: There is evidence that biguanides and sulfonylureas block diclofenac-induced antinociception (DIA in rat models. However, little is known about the interaction between these hypoglycemics with respect to DIA.

  18. Modelling of turbulent hydrocarbon combustion. Test of different reactor concepts for describing the interactions between turbulence and chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, C.; Kremer, H. [Ruhr-Universitaet Bochum, Lehrstuhl fuer Energieanlagentechnik, Bochum (Germany); Kilpinen, P.; Hupa, M. [Aabo Akademi, Turku (Finland). Combustion Chemistry Research Group

    1997-12-31

    The detailed modelling of turbulent reactive flows with CFD-codes is a major challenge in combustion science. One method of combining highly developed turbulence models and detailed chemistry in CFD-codes is the application of reactor based turbulence chemistry interaction models. In this work the influence of different reactor concepts on methane and NO{sub x} chemistry in turbulent reactive flows was investigated. Besides the classical reactor approaches, a plug flow reactor (PFR) and a perfectly stirred reactor (PSR), the Eddy-Dissipation Combustion Model (EDX) and the Eddy Dissipation Concept (EDC) were included. Based on a detailed reaction scheme and a simplified 2-step mechanism studies were performed in a simplified computational grid consisting of 5 cells. The investigations cover a temperature range from 1273 K to 1673 K and consider fuel-rich and fuel-lean gas mixtures as well as turbulent and highly turbulent flow conditions. All test cases investigated in this study showed a strong influence of the reactor residence time on the species conversion processes. Due to this characteristic strong deviations were found for the species trends resulting from the different reactor approaches. However, this influence was only concentrated on the `near burner region` and after 4-5 cells hardly any deviation and residence time dependence could be found. The importance of the residence time dependence increased when the species conversion was accelerated as it is the case for overstoichiometric combustion conditions and increased temperatures. The study focused furthermore on the fine structure in the EDC. Unlike the classical approach this part of the cell was modelled as a PFR instead of a PSR. For high temperature conditions there was hardly any difference between both reactor types. However, decreasing the temperature led to obvious deviations. Finally, the effect of the selective species transport between the cells on the conversion process was investigated

  19. Multiple Homicide as a Function of Prisonization and Concurrent Instrumental Violence: Testing an Interactive Model--A Research Note

    Science.gov (United States)

    DeLisi, Matt; Walters, Glenn D.

    2011-01-01

    Prisonization (as measured by number of prior incarcerations) and concurrent instrumental offending (as measured by contemporaneous kidnapping, rape, robbery, and burglary offenses) were found to interact in 160 multiple-homicide offenders and 494 single-homicide offenders. Controlling for age, gender, race, criminal history, prior incarcerations,…

  20. Testing the measurement equivalence of paper and interactive voice response system versions of the EORTC QLQ-C30

    NARCIS (Netherlands)

    Lundy, J.J.; Coons, S.J.; Aaronson, N.K.

    2014-01-01

    Purpose: The objective of this study was to evaluate the measurement equivalence of an interactive voice response system (IVRS) version and the original paper-based version of the EORTC QLQ-C30. Methods: The QLQ-C30 is a cancer-specific, health-related quality of life questionnaire consisting of

  1. An Observational Approach to Testing Bi-Directional Parent-Child Interactions as Influential to Child Eating and Weight

    Science.gov (United States)

    Demir, Defne; Skouteris, Helen; Dell'Aquila, Daniela; Aksan, Nazan; McCabe, Marita P.; Ricciardelli, Lina A.; Milgrom, Jeannette; Baur, Louise A.

    2012-01-01

    Obesity among children has been on the rise globally for the past few decades. Previous research has centred mainly on self/parent-reported measures examining only uni-directional parental feeding styles and practices. Recent discussions in the literature have raised the importance of bi-directional parent-child interactions in influencing…

  2. Progressive and Regressive Developmental Changes in Neural Substrates for Face Processing: Testing Specific Predictions of the Interactive Specialization Account

    Science.gov (United States)

    Joseph, Jane E.; Gathers, Ann D.; Bhatt, Ramesh S.

    2011-01-01

    Face processing undergoes a fairly protracted developmental time course but the neural underpinnings are not well understood. Prior fMRI studies have only examined progressive changes (i.e. increases in specialization in certain regions with age), which would be predicted by both the Interactive Specialization (IS) and maturational theories of…

  3. Supervisor-employee power distance incompatibility, gender similarity, and relationship conflict: A test of interpersonal interaction theory.

    Science.gov (United States)

    Graham, Katrina A; Dust, Scott B; Ziegert, Jonathan C

    2018-03-01

    According to interpersonal interaction theory, relational harmony surfaces when two individuals have compatible interaction styles. Building from this theory, we propose that supervisor-employee power distance orientation incompatibility will be related to employees' experience of higher levels of relationship conflict with their supervisors. Additionally, we propose an asymmetrical incongruence effect such that relationship conflict will be highest when supervisors are high in power distance and employees are low in power distance. Furthermore, we address calls in interpersonal interaction research for more direct attention to the social context of the dyadic interaction and explore the moderating effects of supervisor-employee gender (dis)similarity on the relationship between this incompatibility and conflict. We propose that supervisor-employee gender dissimilarity (e.g., male-female or female-male pairs) acts as a conditional moderator, neutralizing the power distance incongruence effect and the asymmetrical incongruence effect. Using 259 supervisor-employee dyads in the physical therapy industry, the hypotheses were generally supported. Theoretical and practical implications regarding the unique benefits of power distance compatibility and gender diversity in supervisor-employee dyads are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  4. The Other End of the Leash: An Experimental Test to Analyze How Owners Interact with Their Pet Dogs.

    Science.gov (United States)

    Cimarelli, Giulia; Turcsán, Borbála; Range, Friederike; Virányi, Zsófia

    2017-10-13

    It has been suggested that the way in which owners interact with their dogs can largely vary and influence the dog-owner bond, but very few objective studies, so far, have addressed how the owner interacts with the dog. The goal of the present study was to record dog owners' interaction styles by means of objective observation and coding. The experiment included eight standardized situations in which owners of pet dogs were asked to perform specific tasks including both positive (i.e. playing, teaching a new task, showing a preference towards an object in a food searching task, greeting after separation) and potentially distressing tasks (i.e. physical restriction during DNA sampling, putting a T-shirt onto the dog, giving basic obedience commands while the dog was distracted). The video recordings were coded off-line using a specifically designed coding scheme including scores for communication, social support, warmth, enthusiasm, and play style, as well as frequency of behaviors like petting, praising, commands, and attention sounds. Exploratory Factor Analysis of the 20 variables measured revealed 3 factors, labeled as Owner Warmth, Owner Social Support, and Owner Control, which can be viewed as analogues to parenting style dimensions. The experimental procedure introduced here represents the first standardized measure of interaction styles of dog owners. The methodology presented here is a useful tool to investigate individual variation in the interaction style of pet dog owners that can be used to explain differences in the dog-human relationship, dogs' behavioral outcomes, and dogs stress coping strategies, all crucial elements both from a theoretical and applied point of view.

  5. TRIP-ID: A tool for a smart and interactive identification of Magic Formula tyre model parameters from experimental data acquired on track or test rig

    Science.gov (United States)

    Farroni, Flavio; Lamberti, Raffaele; Mancinelli, Nicolò; Timpone, Francesco

    2018-03-01

    Tyres play a key role in ground vehicles' dynamics because they are responsible for traction, braking and cornering. A proper tyre-road interaction model is essential for a useful and reliable vehicle dynamics model. In the last two decades Pacejka's Magic Formula (MF) has become a standard in simulation field. This paper presents a Tool, called TRIP-ID (Tyre Road Interaction Parameters IDentification), developed to characterize and to identify with a high grade of accuracy and reliability MF micro-parameters from experimental data deriving from telemetry or from test rig. The tool guides interactively the user through the identification process on the basis of strong diagnostic considerations about the experimental data made evident by the tool itself. A motorsport application of the tool is shown as a case study.

  6. [Identification of gene-gene interactions related to the etiology of complex disease: a multifactor dimensionality reduction-genotype pedigree disequilibrium test].

    Science.gov (United States)

    Li, Na; Tang, Xun; Chen, Da-fang; Hu, Yong-hua

    2007-10-01

    To introduce the application of a multifactor dimensionality reduction-genotype pedigree disequilibrium test (MDR-PDT) for detecting gene-gene interactions in the etiology of complex disease. A brief overview on the basic theory, implementing steps and features of MDR-PDT were described, and a practical research case was demonstrated to application of MDR-PDT in nuclear family studies. The MDR-PDT approach was the extension or development of conventional MDR method which could be used for detecting gene-gene interactions in families of diverse structure. MDR-PDT was a new nonparametric and model-free method which might use additional family members in the nuclear families and had a good power to identify gene-gene interactions.

  7. Family-site interaction in Pinus radiata: implications for progeny testing strategy and regionalised breeding in New Zealand.

    Science.gov (United States)

    G.R. Johnson; R.D. Brudon

    1990-01-01

    A progeny test of 170 open-pollinated families from second-generation plus trees of Pinus radiata was established on four sites in New Zealand in 1981. Two test sites were on volcanic purnice soils in the Central North Island region and two were on phosphate-retentive clay soils in the Northland region.Assessments of volume growth, stem straightness, mal-...

  8. Detection of favorable oral cephalosporin-clavulanate interactions by in vitro disk approximation susceptibility testing of extended-spectrum-Beta-lactamase-producing members of the enterobacteriaceae.

    Science.gov (United States)

    Campbell, Jennifer D; Lewis, James S; McElmeel, M Leticia; Fulcher, Letitia C; Jorgensen, James H

    2012-03-01

    Extended-spectrum-beta-lactamase (ESBL)-producing members of the Enterobacteriaceae are often resistant to multiple drug classes, making therapy of urinary infections with oral antibiotics difficult. Previously it was shown that amoxicillin-clavulanate can provide clavulanate inhibition of ESBLs and protect an oral cephalosporin present in combination when tested by broth microdilution. This study has shown that disk approximation testing could detect favorable cephalosporin-clavulanate interactions among a group of 101 previously characterized members of the Enterobacteriaceae with CTX-M, SHV, or TEM ESBLs.

  9. Model-based testing for space-time interaction using point processes: An application to psychiatric hospital admissions in an urban area.

    Science.gov (United States)

    Meyer, Sebastian; Warnke, Ingeborg; Rössler, Wulf; Held, Leonhard

    2016-05-01

    Spatio-temporal interaction is inherent to cases of infectious diseases and occurrences of earthquakes, whereas the spread of other events, such as cancer or crime, is less evident. Statistical significance tests of space-time clustering usually assess the correlation between the spatial and temporal (transformed) distances of the events. Although appealing through simplicity, these classical tests do not adjust for the underlying population nor can they account for a distance decay of interaction. We propose to use the framework of an endemic-epidemic point process model to jointly estimate a background event rate explained by seasonal and areal characteristics, as well as a superposed epidemic component representing the hypothesis of interest. We illustrate this new model-based test for space-time interaction by analysing psychiatric inpatient admissions in Zurich, Switzerland (2007-2012). Several socio-economic factors were found to be associated with the admission rate, but there was no evidence of general clustering of the cases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Testing co-evolutionary hypotheses over geological timescales: interactions between Mesozoic non-avian dinosaurs and cycads.

    Science.gov (United States)

    Butler, Richard J; Barrett, Paul M; Kenrick, Paul; Penn, Malcolm G

    2009-02-01

    The significance of co-evolution over ecological timescales is well established, yet it remains unclear to what extent co-evolutionary processes contribute to driving large-scale evolutionary and ecological changes over geological timescales. Some of the most intriguing and pervasive long-term co-evolutionary hypotheses relate to proposed interactions between herbivorous non-avian dinosaurs and Mesozoic plants, including cycads. Dinosaurs have been proposed as key dispersers of cycad seeds during the Mesozoic, and temporal variation in cycad diversity and abundance has been linked to dinosaur faunal changes. Here we assess the evidence for proposed hypotheses of trophic and evolutionary interactions between these two groups using diversity analyses, a new database of Cretaceous dinosaur and plant co-occurrence data, and a geographical information system (GIS) as a visualisation tool. Phylogenetic evidence suggests that the origins of several key biological properties of cycads (e.g. toxins, bright-coloured seeds) likely predated the origin of dinosaurs. Direct evidence of dinosaur-cycad interactions is lacking, but evidence from extant ecosystems suggests that dinosaurs may plausibly have acted as seed dispersers for cycads, although it is likely that other vertebrate groups (e.g. birds, early mammals) also played a role. Although the Late Triassic radiations of dinosaurs and cycads appear to have been approximately contemporaneous, few significant changes in dinosaur faunas coincide with the late Early Cretaceous cycad decline. No significant spatiotemporal associations between particular dinosaur groups and cycads can be identified - GIS visualisation reveals disparities between the spatiotemporal distributions of some dinosaur groups (e.g. sauropodomorphs) and cycads that are inconsistent with co-evolutionary hypotheses. The available data provide no unequivocal support for any of the proposed co-evolutionary interactions between cycads and herbivorous dinosaurs

  11. Alloy development for irradiation performance. Quarterly progress report for period ending December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Ashdown, B.G. (comp.)

    1980-04-01

    Progress is reported concerning preparation of a materials handbook for fusion, creep-fatigue of first-wall structural materials, test results on miniature compact tension fracture toughness specimens, austenitic stainless steels, Fe-Ni-Cr alloys, iron-base alloys with long-range crystal structure, ferritic steels, irradiation experiments, corrosion testing, and hydrogen permeation studies. (FS)

  12. Are trade-offs among species' ecological interactions scale dependent? A test using pitcher-plant inquiline species.

    Science.gov (United States)

    Kneitel, Jamie M

    2012-01-01

    Trade-offs among species' ecological interactions is a pervasive explanation for species coexistence. The traits associated with trade-offs are typically measured to mechanistically explain species coexistence at a single spatial scale. However, species potentially interact at multiple scales and this may be reflected in the traits among coexisting species. I quantified species' ecological traits associated with the trade-offs expected at both local (competitive ability and predator tolerance) and regional (competitive ability and colonization rate) community scales. The most common species (four protozoa and a rotifer) from the middle trophic level of a pitcher plant (Sarracenia purpurea) inquiline community were used to link species traits to previously observed patterns of species diversity and abundance. Traits associated with trade-offs (competitive ability, predator tolerance, and colonization rate) and other ecological traits (size, growth rate, and carrying capacity) were measured for each of the focal species. Traits were correlated with one another with a negative relationship indicative of a trade-off. Protozoan and rotifer species exhibited a negative relationship between competitive ability and predator tolerance, indicative of coexistence at the local community scale. There was no relationship between competitive ability and colonization rate. Size, growth rate, and carrying capacity were correlated with each other and the trade-off traits: Size was related to both competitive ability and predator tolerance, but growth rate and carrying capacity were correlated with predator tolerance. When partial correlations were conducted controlling for size, growth rate and carrying capacity, the trade-offs largely disappeared. These results imply that body size is the trait that provides the basis for ecological interactions and trade-offs. Altogether, this study showed that the examination of species' traits in the context of coexistence at different scales

  13. Are trade-offs among species' ecological interactions scale dependent? A test using pitcher-plant inquiline species.

    Directory of Open Access Journals (Sweden)

    Jamie M Kneitel

    Full Text Available Trade-offs among species' ecological interactions is a pervasive explanation for species coexistence. The traits associated with trade-offs are typically measured to mechanistically explain species coexistence at a single spatial scale. However, species potentially interact at multiple scales and this may be reflected in the traits among coexisting species. I quantified species' ecological traits associated with the trade-offs expected at both local (competitive ability and predator tolerance and regional (competitive ability and colonization rate community scales. The most common species (four protozoa and a rotifer from the middle trophic level of a pitcher plant (Sarracenia purpurea inquiline community were used to link species traits to previously observed patterns of species diversity and abundance. Traits associated with trade-offs (competitive ability, predator tolerance, and colonization rate and other ecological traits (size, growth rate, and carrying capacity were measured for each of the focal species. Traits were correlated with one another with a negative relationship indicative of a trade-off. Protozoan and rotifer species exhibited a negative relationship between competitive ability and predator tolerance, indicative of coexistence at the local community scale. There was no relationship between competitive ability and colonization rate. Size, growth rate, and carrying capacity were correlated with each other and the trade-off traits: Size was related to both competitive ability and predator tolerance, but growth rate and carrying capacity were correlated with predator tolerance. When partial correlations were conducted controlling for size, growth rate and carrying capacity, the trade-offs largely disappeared. These results imply that body size is the trait that provides the basis for ecological interactions and trade-offs. Altogether, this study showed that the examination of species' traits in the context of coexistence at

  14. WWC Review of the Report "Interactive Online Learning on Campus: Testing MOOCs and Other Platforms in Hybrid Formats in the University System of Maryland." What Works Clearinghouse Single Study Review

    Science.gov (United States)

    What Works Clearinghouse, 2015

    2015-01-01

    In the 2014 study, "Interactive Online Learning on Campus: Testing MOOCs and Other Platforms in Hybrid Formats in the University System of Maryland," researchers examined the impact of using hybrid forms of interactive online learning in seven undergraduate courses across seven universities in Maryland. Hybrid forms of interactive online…

  15. Test of nucleon-nucleon interaction by p vector-d vector polarization transfer in the three-nucleon system

    International Nuclear Information System (INIS)

    Sperisen, F.; Gruebler, W.; Koenig, V.; Schmelzbach, P.A.; Elsener, K.; Jenny, B.; Schweizer, C.; Ulbricht, J.; Doleschall, P.

    1982-01-01

    Measurements of three vector-to-vector and seven vector-to-tensor polarization transfer coefficients of the 2 H(p vector, d vector) 1 H elastic scattering at Esub(p) = 10 MeV are reported in the angular range between THETAsub(cm) = 92 0 and 180 0 . These second-order observables are compared with Faddeev calculations. It is shown that the vector-to-tensor components depend largely on the details of the N-N P-wave interaction. (orig.)

  16. Testing T-odd, p-even interactions with gamma-rays from neutron p-wave resonances

    International Nuclear Information System (INIS)

    Barabanov, A.L.

    1992-01-01

    A new method for the study of time reversal violation is described. It consists of measurements of the forward-backward asymmetry in individual gamma-ray transitions resulting from unpolarized neutron capture in p-wave resonance. An experiment with a 113 Cd target performed at the Dubna pulsed neutron source has been analyzed and a limit on the time reversal odd, parity even interaction extracted. The possibilities of experiments using the powerful pulsed neutron source at Los Alamos are considered. 23 refs.; 2 figs

  17. Test of High-pT Scaling from Cosmic-Ray Interactions up to 400 TeV

    Science.gov (United States)

    Hazen, W. E.; Hendel, A. Z.; Ash, A. G.; Foster, J. M.; Hodson, A. L.; Porter, M. R.; Bull, R. M.

    1982-05-01

    The rate of subcores in cosmic-ray air showers has been measured near sea level with a close-packed 35-m2 array of spark chambers at Leeds. Auxiliary experiments demonstrate that our transition effects are negligible. The rate of subcores versus shower size is translated into the rate of high-pT events versus energy of the interacting hadron. Comparison with calculations of Halzen favors pT-4 over pT-8 scaling. The highest energy bin is centered on 350 TeV.

  18. Effects of Zr-hydride distribution of irradiated Zircaloy-2 cladding in RIA-simulating pellet-clad mechanical interaction testing

    Directory of Open Access Journals (Sweden)

    Per Magnusson

    2018-03-01

    Full Text Available A series of simulated reactivity-initiated accident (RIA tests on irradiated fully recrystallized boiling water reactor Zircaloy-2 cladding has been performed by means of the expansion-due-to-compression (EDC test method. The EDC method reproduces fuel pellet–clad mechanical interaction (PCMI conditions for the cladding during RIA transients with respect to temperature and loading rates by out-of-pile mechanical testing. The tested materials had a large variation in burnup and hydrogen content (up to 907 wppm. The results of the EDC tests showed variation in the PCMI resistance of claddings with similar burnup and hydrogen content, making it difficult to clearly identify ductile-to-brittle transition temperatures. The EDC-tested samples of the present and previous work were investigated by light optical and scanning electron microscopy to study the influence of factors such as azimuthal variation of the Zr-hydrides and the presence of hydride rims and radially oriented hydrides. Two main characteristics were identified in samples with low ductility with respect to hydrogen content and test temperature: hydride rims and radial hydrides at the cladding outer surface. Crack propagation and failure modes were also studied, showing two general modes of crack propagation depending on distribution and amount of radially oriented hydrides. It was concluded that the PCMI resistance of irradiated cladding under normal conditions with homogenously distributed circumferential hydrides is high, with good margin to the RIA failure limits. To further improve safety, focus should be on conditions causing nonfavorable hydride distribution, such as hydride reorientation and formation of hydride blisters at the cladding outer surface. Keywords: Failure, Hydrides, Hydrogen Content, Pellet–Clad Mechanical Interaction, Reactivity-Initiated Accident, Transient

  19. The experimental setup of the Interaction in Crystals for Emission of RADiation collaboration at Mainzer Mikrotron: Design, commissioning, and tests

    Energy Technology Data Exchange (ETDEWEB)

    Lietti, D., E-mail: Daniela.Lietti@cern.ch [Università degli Studi dell’Insubria, Via Valleggio 11, 22100 Como (Italy); Backe, H.; Lauth, W. [Institut für Kernphysik der Universität Mainz, D-55099 Mainz (Germany); Bagli, E.; Bandiera, L.; Germogli, G.; Guidi, V.; Mazzolari, A. [Università degli Studi di Ferrara, Via Saragat 1, 44100 Ferrara (Italy); INFN Sezione di Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Berra, A.; Prest, M. [Università degli Studi dell’Insubria, Via Valleggio 11, 22100 Como (Italy); INFN Sezione di Milano Bicocca, Piazza della Scienza 3, 20126 Milano (Italy); Carturan, S.; De Salvador, D. [Università degli Studi di Padova, Via Marzolo 8, 35131 Padova (Italy); INFN Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Legnaro (Italy); Vallazza, E. [INFN Sezione di Trieste, Via Valerio 2, 34127 Trieste (Italy)

    2015-04-15

    Silicon/germanium flat/bent crystals are thin devices able to efficiently deflect charged particle GeV-energy beams up to a few hundreds of μrad; moreover, high intensity photons can be efficiently produced in the so-called Multi-Volume Reflection (MVR) and Multiple Volume Reflections in One Crystal (MVROC) conditions. In the last years, the research interest in this field has moved to the dynamic studies of light negative leptons in the low energy range: the possibility to deflect negative particles and to produce high intensity γ sources via the coherent interactions with crystals in the sub-GeV energy range has been proved by the ICE-RAD (Interaction in Crystals for Emission of RADiation) Collaboration at the MAinzer MIkrotron (MAMI, Germany). This paper describes the setup used by the ICE-RAD experiment for the crystals characterization (both in terms of deflection and radiation emission properties): a high precision goniometer is used to align the crystals with the incoming beam, while a silicon based profilometer and an inorganic scintillator reconstruct, respectively, the particle position and the photon spectra after the samples. The crystals manufacturing process and their characterization, the silicon profilometer commissioning at the CERN PS T9 beamline, and the commissioning of the whole setup installed at MAMI are presented.

  20. USING A PROBLEM SITUATION IN A COMPREHENSIVE TEST (BASED ON THE EXAMPLE OF PREPARATION FOR INTERCULTURAL BUSINESS INTERACTIONS WITHIN THE ASIAN PACIFIC RIM

    Directory of Open Access Journals (Sweden)

    Albina G. Dolgan

    2016-06-01

    Full Text Available Introduction: nowadays Russian people are proactively seeking cooperation with the Asian Pacific Rim. Considering this the author has developed a curricular for institutions of higher learning training students in intercultural business interaction in this region within such disciplines as “Foreign language” and “Professional foreign language”. Materials and Methods: the author puts forward a comprehensive test as a way to define the level of students’ preparedness for business interaction within the Asian Pacific Rim, to test that they understand what they learn and to identify qualitative indicators attending to acquisition of content, and development of communicative and linguistic competences, as well as such necessary characteristics as pragmatism and tolerance. The comprehensive test elaboration was based on A. A. Verbitskiy and E. E. Kreslavskaya’s method of assessing the students’ understanding of meaning and significance of information. Results: drawing upon ideas of researchers studying intercultural communication, East Asian peoples’ values, region’s social, cultural and economic problems, the author proposes some special direction for the learning process – it should orient the Far Eastern students to take into consideration values, behaviours, mental and cultural specifics of partners from China, Korea, Japan and other neighboring countries in the business interaction. It is impossible to subdivide such interaction into professional and social spheres, so the author has chosen a problem situation to be a basic form for organising the learning process. The prob- lem situations of the social and professional character have been taken from East Asia business practices. Discussion and Conclusions: to solve the problem how to check students’ understanding of the learning information, the author has developed a comprehensive test where a problem situation is also used. The paper’s objective is to show how these

  1. Experimental simulations of interactions between glass and environmental materials, from laboratory benches to in-site testing

    International Nuclear Information System (INIS)

    Godon, N.

    1997-01-01

    This paper summarizes the results of 26 long-duration tests simulating a variety of storage conditions. The effects of the back-filling materials, glass cracking and the nature of the host rock are discussed. Moreover, two experiments have been in progress for over 15 and 7 years in a granite medium and a clay medium. (author)

  2. The Shock and Vibration Bulletin. Part 2. Dynamic Testing, Flight Vehicle Dynamics, Seismic Loads and Fluid-Structure Interaction

    Science.gov (United States)

    1985-06-01

    a different 10 %Q % % ..... r...*.axs ..vel rec 10g ateral ross ... ined. o..e.cXYa ..... axi (X).leve..rea..............directi.Wi.h..h.excep.io.o...such magnitude resistive charge for a given strain. as to overdrive the amplifiers. In future tests it is essential that Another important aspect of the

  3. How do Nutritional Stress and La Crosse Virus Infection Interact? Tests for Effects on Willingness to Blood Feed and Fecundity in Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Westby, Katie M; Muturi, Ephantus J; Juliano, Steven A

    2016-01-01

    Evolutionary theory predicts that vector-borne pathogens should have low virulence for their vector because of selection against pathogens that harm the vector sufficiently to reduce transmission. Environmental factors such as nutritional stress can alter vector-pathogen associations by making the vectors more susceptible to pathogens (condition-dependent competence) and vulnerable to the harm caused by pathogen replication (condition-dependent virulence). We tested the hypotheses of condition-dependent competence and condition-dependent virulence by examining the interactive effects of short-term sugar deprivation and exposure to La Crosse virus (LACV) in female Aedes albopictus (Skuse). We predicted that infection status interacts with sugar deprivation to alter willingness to blood feed and fecundity in the second gonotrophic cycle (condition-dependent virulence). Sugar deprivation had no effect on body infection or disseminated infection rates. Infection status, sugar treatment, and their interaction had no effect on fecundity. Mosquitoes that had intermittent access to sugar were significantly more willing to take a second bloodmeal compared with those that had continuous access to sugar. Infection status and the interaction with sugar treatment had no effect on blood-feeding behavior. Thus, we found no evidence of short-term sugar deprivation leading to condition-dependent competence for, or condition-dependent virulence of, LACV in Ae. albopictus. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Reinforcement and punishment of substance abuse during ongoing interactions: a conversational test of inconsistent nurturing as control theory.

    Science.gov (United States)

    Duggan, Ashley P; Dailey, Rene M; Le Poire, Beth A

    2008-01-01

    This study is the first to examine inconsistent nurturing as control (INC) theory during ongoing interpersonal influence episodes between substance-abusive individuals and their romantic partners. This study sought to determine how nonverbal (i.e., kinesic and vocalic) and verbal reinforcement and punishment of substance-abusive behavior during actual interactions influenced substance-abusive individuals' recidivism and perceptions of non-using partners' persuasive effectiveness. The findings reveal that consistent verbal punishment of substance abuse (e.g., threats, nagging) predicted lower relapse, while verbal reinforcement (e.g., telling the partner they are more fun when they use) predicted higher relapse. With regard to nonverbal communication, vocalic punishment and vocalic reinforcement predicted relapse and persuasive effectiveness. Results suggest the combination of behaviors resemble intermittent reinforcement and punishment and should actually strengthen the substance-abusive behavior the partner is trying to curtail.

  5. Tests of the SIBYLL 2.3 high-energy hadronic interaction model using the KASCADE-Grande muon data

    Directory of Open Access Journals (Sweden)

    Arteaga-Velázquez J.C.

    2018-01-01

    Full Text Available The KASCADE-Grande observatory was a ground-based air shower array dedicated to study the energy and composition of cosmic rays in the energy interval E = 1 PeV –1 EeV. The experiment consisted of different detector systems which allowed the simultaneous measurement of distinct components of air showers (EAS, such as the muon content. In this contribution, we study the total muon number and the lateral density distribution of muons in EAS detected by KASCADE-Grande as a function of the zenith angle and the total number of charged particles. The attenuation length of the muon content of EAS is also measured. The results are compared with the predictions of the SIBYLL 2.3 high-energy hadronic interaction model.

  6. The synchronous neural interactions test as a functional neuromarker for post-traumatic stress disorder (PTSD): a robust classification method based on the bootstrap

    Science.gov (United States)

    Georgopoulos, A. P.; Tan, H.-R. M.; Lewis, S. M.; Leuthold, A. C.; Winskowski, A. M.; Lynch, J. K.; Engdahl, B.

    2010-02-01

    Traumatic experiences can produce post-traumatic stress disorder (PTSD) which is a debilitating condition and for which no biomarker currently exists (Institute of Medicine (US) 2006 Posttraumatic Stress Disorder: Diagnosis and Assessment (Washington, DC: National Academies)). Here we show that the synchronous neural interactions (SNI) test which assesses the functional interactions among neural populations derived from magnetoencephalographic (MEG) recordings (Georgopoulos A P et al 2007 J. Neural Eng. 4 349-55) can successfully differentiate PTSD patients from healthy control subjects. Externally cross-validated, bootstrap-based analyses yielded >90% overall accuracy of classification. In addition, all but one of 18 patients who were not receiving medications for their disease were correctly classified. Altogether, these findings document robust differences in brain function between the PTSD and control groups that can be used for differential diagnosis and which possess the potential for assessing and monitoring disease progression and effects of therapy.

  7. Application of Hastelloy X in Gas-Cooled Reactor Systems

    DEFF Research Database (Denmark)

    Brinkman, C. R.; Rittenhouse, P. L.; Corwin, W.R.

    1976-01-01

    Hastelloy X, an Ni--Cr--Fe--Mo alloy, may be an important structural alloy for components of gas-cooled reactor systems. Expected applications of this alloy in the High-Temperature Gas-Cooled Reactor (HTGR) are discussed, and the development of interim mechanical properties and supporting data...... are reported. Properties of concern include tensile, creep, creep-rupture, fatigue, creep-fatigue interaction, subcritical crack growth, thermal stability, and the influence of helium environments with controlled amounts of impurities on these properties. In order to develop these properties in helium...... extensive amount of information has been generated on this material at Oak Ridge National Laboratory and elsewhere concerning behavior in air, which is reviewed. However, only limited data are available from tests conducted in helium. Comparisons of the fatigue and subcritical growth behavior in air between...

  8. Survey on structural material investigations for the primary circuit of the SNR 300

    International Nuclear Information System (INIS)

    Grosser, E.D.; Lorenz, H.

    1977-01-01

    The material programs described so far cover major Important areas of structural material behavior in the primary system of a sodium cooled reactor. The results demonstrate that a good base is available for the design and safe operation of sodium systems. For complementation purposes some further work is needed in certain areas: creep-fatigue interaction mechanism and description of base material and weld metal behavior for design purposes, irradiation effects in the low-dose range on time-dependent material behavior, impact of heat-to-heat variation on materials properties data, establishment of a profound data base to evaluate sodium impact on mechanical properties, application of the leak-before-break concept in plant design, confirmation of laboratory test results by the operational experience of sodium cooled reactor systems. (author)

  9. Sexual videos in Internet: a test of 11 hypotheses about intimate practices and gender interactions in Latin America

    OpenAIRE

    Monge-Nájera, Julián; Corrales, Karla Vega

    2015-01-01

    There is a marked lack of literature on user-submitted sexual videos from Latin America. To start filling that gap, we present a formal statistical testing of several hypotheses about the characteristics of 214 videos from Nereliatube.com posted from the inauguration of the site until December 2010. We found that in most cases the video was made consensually and the camera was operated by the man. The most frequent practice shown was fellatio, followed by vaginal penetration.  The great major...

  10. Effects of oxidation on high-temperature mechanical properties of alloy 600: application to cracking in primary water of nuclear pressurized water reactors

    International Nuclear Information System (INIS)

    Gourgues, A.F.

    1997-09-01

    Since the early 1970's certain component parts of the primary loops of nuclear pressurised water reactors, such as steam generator tubing and pressure vessel head penetrations, have been affected by intergranular stress corrosion cracking. This form of cracking, which occurs after several thousand hours, initiates on the component side exposed to primary water. The purpose of this study is to gain a better understanding of the cracking mechanism. The focus is on the interactions between the local mechanical loading conditions and the effects of an oxidising environment. Fatigue and creep fatigue crack propagation tests were carried out using CT specimens. The local mechanical loading conditions were determined by finite element calculations. The oxidation behaviour was studied by transmission electron microscopy. Creep tests were conducted on thin sheet samples to investigate the effects of environment on the creep properties. Intergranular crack propagation, as determined at 550 deg C in air and in vacuum, has been related to a creep damage mechanism. Dislocation creep deformation mechanisms, which appear to induce intergranular damage in this material at high temperature, are enhanced when the growing oxide scale is nickel- or iron-rich, compared to the results obtained in high vacuum with the protective chromium oxide scale. Thus, intergranular fracture, which occurs in all environmental conditions under creep fatigue cycles, occurs even under fatigue cycles when creep is enhanced. Fatigue crack propagation tests at 400 deg C gave essentially the same results as those obtained at 550 deg C. Crack propagation tests in deaerated water, either in low pressure vapour at 400 deg C or in primary water at 320 deg C, lead to the same cracking results. The fracture surfaces were identical to those observed after conventional stress corrosion cracking tests. For these environmental conditions, the enhanced creep model was also proposed to account for the experimental

  11. IFMIF target and test cell - design and integration

    International Nuclear Information System (INIS)

    Heinzel, V.

    2007-01-01

    The International Fusion Material Irradiation Facility (IFMIF) aims at the qualification of appropriate materials for a Demonstration Fusion Power Plant (DEMO) to a fluence of up to 150 dpa (displacement per atom) at a DEMO typical neutron spectrum. It comprises two accelerators each providing a deuteron beam with 125 mA and 40 MeV. The deuterons strike a lithium target and create via stripping reactions neutrons. The neutrons are mainly forward directed into the High-Flux-Test-Module (HFTM). The Medium Flux-Test-Modules (MFTM) and the Low-Flux-Test-Modules (LFTM) are arranged in beam direction behind. In the HFTM a damage rate in steel of more than 20 dpa/fpy (displacement per atome per full power year) will be provide in a volume of 0.5 litre. The neutron spectrum is prone to produce helium and tritium in steel like in the first wall of a DEMO reactor. The Medium- Flux-Test-Modules are designed for creep fatigues in situ and tritium release test. The test modules are cooled with helium. The target is a lithium jet with a free surface towards the deuteron beams. The jet follows a concave curved so called back wall. Centrifugal forces increase the static pressure, which prevents lithium boiling at the beam tube pressure and the power release of 10 MW due to the deuteron beams. The target and Test Cell (TTC) houses the target and the test modules as well as the lithium supply tubes and a quench tank into which the lithium splashes after the target. The lithium containing components have a temperature of 250 to 350 C. Nuclear reactions mainly in beam direction contribute to heat releases in TTC components. The TTC is filled with a noble gas with almost atmospheric pressure. Natural convection transfers heat to the walls but also mitigates temperature peaks. The Forschungszentrum Karlsruhe (FZK) has developed or validated tools for: - The extended Monte Carlo Code McDeLicious for calculations of the neutron source term, dpa rates in the material specimens, activation

  12. Thrill Seeking and Religiosity in Relation to Adolescent Substance Use: Tests of Joint, Interactive, and Indirect Influences

    Science.gov (United States)

    Mason, W. Alex; Spoth, Richard L.

    2011-01-01

    Thrill seeking is a robust positive predictor of adolescent substance use. Religiosity is negatively associated with substance use among teens, although findings are mixed. Few studies have examined the interplay between these two prominent risk and protective factors. The current study addresses this gap by examining the joint, interactive, and indirect influences of thrill seeking and each of two dimensions of religiosity, religious salience and religious attendance, in relation to adolescent substance use. Participants were 667 rural youths (345 girls and 322 boys) and their families participating in a longitudinal family-focused prevention trial. Data were collected via self-report surveys at six time points across seven years, spanning ages 11 through 18. Results from latent growth curve analyses showed that both religious salience and religious attendance growth factors were associated negatively with late adolescent substance use, while adjusting for thrill seeking and selected covariates. Although the link between thrill seeking and substance use was not moderated by religiosity, there was a statistically significant indirect effect of thrill seeking on the outcome through a faster rate of downturn in religious attendance. Family intervention also predicted a slower rate of downturn in religious attendance and was associated negatively with substance use in late adolescence. Early adolescent substance use predicted a faster rate of decrease in religious salience throughout the teen years. The pattern of associations was similar for boys and girls. Findings suggest that teens who are elevated on thrill seeking could be targeted for specially-designed substance use prevention programs and provide additional evidence for the efficacy of family interventions. PMID:21574673

  13. Study on high temperature design methodology of heat-resistant materials for GEN-IV systems

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Woo Seog; Kim, D. W.; Kim, S. H.; Kim, W. G.; Kim, J. H.; Park, D. G.; Yoon, J. H.; Lee, H. Y.; Hing, J. H

    2005-08-15

    Analysis of the existing high temperature design and assessment codes such as US(ASME-NH,Draft Code Case for Alloy 617), France(RCC-MR), UK(R5), Japan(BDS/DDS/FDS) for Gen IV reactor structure has been carried out. In addition the scope and fields for research and development is needed in the future have been defined. For assessing the high temperature creep cracks, time dependent fracture mechanics (TDFM) parameters of the C and Ct were analyzed. The creep propagation data were obtained from the creep crack growth tests for type 316LN stainless steels, and creep crack growth testing machine for Gen-IV system up to 950 .deg. C was set up. Damage mechanism and causes for creep-fatigue were investigated. The difference between prediction creep-fatigue life and experimental life were investigated. Material properties for analysis creep-fatigue damage were recommended. The assessment procedure (Draft) on creep-fatigue crack initiation has been developed based on the technical appendix A16 of French RCC-MR code. Ultrasonic wave signal against creep ruptured specimens of type 316LN stainless steel was obtained. It was identified that creep damage can be evaluated by ultrasonic method. The NDT techniques evaluated include Barkhausen noise, magnetic hysteresis parameters, positron annihilation, X-ray diffraction and small angle neutron scattering. Experimental procedure and evaluation method of material integrity were developed through the fracture toughness test of Cr-Mo steel.

  14. Genotype-environment interaction and the number of test sites for the genetic improvement of rubber trees (Hevea in São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Costa Reginaldo Brito da

    2000-01-01

    Full Text Available The present study quantifies the possible genotype-environment interactions and determines the ideal number of test sites for rubber trees [Hevea brasiliensis (Willd ex Adr. de Juss. Muell Arg] in the plateau region of São Paulo State. The study was based on the genetic correlation among progenies at three different sites and on estimates of genetic gains with indirect selection of rubber trees. Twenty-two half-sib progenies were planted at the Jaú, Pindorama and Votuporanga experimental stations using random blocks with five replications and 10 plants per plot. At three years of age, the plants were evaluated for their total number of latex ring vessels (NR, rubber production (RP, bark thickness (BT and girth (SG. There was significant genetic variability in the characters RP, SG and BT, mainly among progenies from Pindorama and Votuporanga. The effects of genotype-site interactions were significant for RP and SG. The finding of significant interactions was not a complicating factor because of the large genetic correlation detected. These results indicate that the use of two sites is more profitable when the gains in efficiency of selection are greater than 10%. Thus, Pindorama and Votuporanga will satisfactorily attend the studied region.

  15. Formation of outflow channels on Mars: Testing the origin of Reull Vallis in Hesperia Planum by large-scale lava-ice interactions and top-down melting

    Science.gov (United States)

    Cassanelli, James P.; Head, James W.

    2018-05-01

    The Reull Vallis outflow channel is a segmented system of fluvial valleys which originates from the volcanic plains of the Hesperia Planum region of Mars. Explanation of the formation of the Reull Vallis outflow channel by canonical catastrophic groundwater release models faces difficulties with generating sufficient hydraulic head, requiring unreasonably high aquifer permeability, and from limited recharge sources. Recent work has proposed that large-scale lava-ice interactions could serve as an alternative mechanism for outflow channel formation on the basis of predictions of regional ice sheet formation in areas that also underwent extensive contemporaneous volcanic resurfacing. Here we assess in detail the potential formation of outflow channels by large-scale lava-ice interactions through an applied case study of the Reull Vallis outflow channel system, selected for its close association with the effusive volcanic plains of the Hesperia Planum region. We first review the geomorphology of the Reull Vallis system to outline criteria that must be met by the proposed formation mechanism. We then assess local and regional lava heating and loading conditions and generate model predictions for the formation of Reull Vallis to test against the outlined geomorphic criteria. We find that successive events of large-scale lava-ice interactions that melt ice deposits, which then undergo re-deposition due to climatic mechanisms, best explains the observed geomorphic criteria, offering improvements over previously proposed formation models, particularly in the ability to supply adequate volumes of water.

  16. FY16 Status Report on Development of Integrated EPP and SMT Design Methods

    Energy Technology Data Exchange (ETDEWEB)

    Jetter, R. I. [R.I. Jetter Consulting, Pebble Beach, CA (United States); Sham, T. -L. [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Y. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-01

    The goal of the Elastic-Perfectly Plastic (EPP) combined integrated creep-fatigue damage evaluation approach is to incorporate a Simplified Model Test (SMT) data based approach for creep-fatigue damage evaluation into the EPP methodology to avoid the separate evaluation of creep and fatigue damage and eliminate the requirement for stress classification in current methods; thus greatly simplifying evaluation of elevated temperature cyclic service. The EPP methodology is based on the idea that creep damage and strain accumulation can be bounded by a properly chosen “pseudo” yield strength used in an elastic-perfectly plastic analysis, thus avoiding the need for stress classification. The original SMT approach is based on the use of elastic analysis. The experimental data, cycles to failure, is correlated using the elastically calculated strain range in the test specimen and the corresponding component strain is also calculated elastically. The advantage of this approach is that it is no longer necessary to use the damage interaction, or D-diagram, because the damage due to the combined effects of creep and fatigue are accounted in the test data by means of a specimen that is designed to replicate or bound the stress and strain redistribution that occurs in actual components when loaded in the creep regime. The reference approach to combining the two methodologies and the corresponding uncertainties and validation plans are presented. Results from recent key feature tests are discussed to illustrate the applicability of the EPP methodology and the behavior of materials at elevated temperature when undergoing stress and strain redistribution due to plasticity and creep.

  17. Determination of N-acetylglucosamine in cosmetic formulations and skin test samples by hydrophilic interaction liquid chromatography and UV detection.

    Science.gov (United States)

    Pedrali, Alice; Bleve, Mariella; Capra, Priscilla; Jonsson, Tobias; Massolini, Gabriella; Perugini, Paola; Marrubini, Giorgio

    2015-03-25

    N-Acetylglucosamine is an ingredient in pharmaceuticals, nutritional supplements and in cosmetics. N-Acetylglucosamine in cosmetics is expected to improve skin hydration, reparation, and to contribute as anti-wrinkle agent. This study reports on the validation and application of an HPLC method based on HILIC and UV detection for determining N-acetylglucosamine in cosmetics and in samples obtained after testing the skin exposed to cosmetics formulations. The chromatographic column used is a ZIC(®)-pHILIC (150 mm × 4.6 mm, 5 μm particle size) on which a mobile phase containing acetonitrile-aqueous KH2PO4 (70:30, v/v) 15 mM was applied in isocratic elution mode injecting 20 μl of sample at 0.5 ml/min constant flow-rate and 10±1°C column temperature. Under these conditions the total run time was 10 min and N-acetylglucosamine eluted baseline separated from all other compounds in the samples. Calibration in the range from 40 to 80 μg/ml allowed to assess the method linearity (R(2)>0.999) in a concentration range corresponding to about 50% to 120% of the expected levels of N-acetylglucosamine in the formulations. Precision expressed by RSD% was always better than 2% in intra-day and inter-day assays of authentic samples. Accuracy was in all cases within 95-105% of the expected concentration value in formulations containing N-acetylglucosamine. The sensitivity of the method was at the level of 10 μg/ml as limit of detection, and at 40 μg/ml as limit of quantitation. The application of the method to formulations containing solid lipid nanoparticles documents its usefulness in cosmetic quality control. The results witness that the method is also suitable for the determination of N-acetylglucosamine in samples obtained from skin test strips. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Kinematic reconstruction of tau leptons and test for lepton universality in charged weak interactions with the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Sauerland, Philip

    2011-04-15

    The Standard Model of Particle Physics (SM) postulates the universal coupling of the three lepton families to the weak current. The most precise measurement of lepton universality in W decays comes from the four experiments at the Large Electron-Positron Collider (LEP). If one compares the couplings of muons and tau leptons to the charged weak current, there is a discrepancy of nearly three standard deviations w.r.t. the SM expectation. There are models beyond the SM, which could explain the violation of lepton universality with new physics processes, if it is more than a statistical fluctuation. The Large Hadron Collider (LHC) offers a great opportunity to study decays of the charged-weak gauge bosons at very high event rates and at unmatched collision energies. This thesis presents an analysis strategy to test lepton universality with the Compact Muon Solenoid experiment (CMS) at the LHC. The analysis focusses on the decays of the W{sup {+-}} boson to particles of the second and third lepton family. For this purpose detector-simulated proton-proton events are used. The identification and reconstruction of tau leptons is a difficult task at the LHC. The reconstruction is often restricted by the limited precision of the commonly used collinear approximation. The application of a kinematic fit to particular tau-decay modes can improve the experimental resolution and provides an efficient background suppression. The development of such a fit with kinematic constraints derived from the topology of the decay {tau} {yields} 3{pi}{sup {+-}} + {nu}{sub {tau}} is described. The kinematic fit of tau leptons is not limited to the test for lepton universality, but can be deployed by various physics analyses in a broad energy range of the tau leptons. The event topology of W{sup {+-}} decays with leptonic final states is studied. Two event selections are developed: one for the W{sup {+-}} {yields} {tau}{nu} and one for the W{sup {+-}} {yields} {mu}{nu} decay. A common online

  19. Effects of sodium environment on the mechanical properties of Fe-2 1/4Cr-1Mo steel

    International Nuclear Information System (INIS)

    Chopra, O.K.

    1983-09-01

    Mechanical property data on isothermally annealed, thermally aged, and sodium-exposed Fe-2 1/4Cr-1Mo steel are analyzed to evaluate the influence of the sodium environment as well as the effects of the microstructural and compositional changes that occur in the steel during long-term exposure to sodium. Correlations are developed to predict the environmental effects on tensile, creep, fatigue, and creep-fatigue properties of Fe-2 1/4Cr-1Mo steel in sodium. The results indicate that at temperatures 0 C), degradation of mechanical properties is essentially due to thermal aging. Loss of carbon from the steel reduces both the tensile and creep-rupture strength, but has little or no effect on the fatigue properties. The cyclic properties of Fe-2 1/4Cr-1Mo steel in sodium are superior to those in air. The creep-fatigue behavior in sodium is significantly different from that in an air environment. The creep-fatigue data are analyzed using the interactive damage rate equations to predict the time-dependent fatigue behavior of isothermally annealed Fe-2 1/4Cr-1Mo steel in sodium. 15 references, 7 figures, 1 table

  20. Interaction between Cannabinoidergic System and H2 Receptors in CA1 Region upon Anxiety-like Behaviors in Hole-Board Test

    Directory of Open Access Journals (Sweden)

    M Nasehi

    2012-05-01

    Full Text Available

    Background and Objectives: Cannabinoids produce a wide array of effects on different species and interact with different neurotransmitter systems in the brain. In the present study, the effects of histaminergic and cannabinoidregic systems as well as their interactions on anxiety-related behaviors were examined on mice. Methods: In this study, at first mice were anesthetized with intra-peritoneal injection of ketamine hydrochloride and xylazine. They were then placed in a stereotaxic apparatus. Two stainless-steel cannuale were placed one mm above CA1 regions of the dorsal hippocampus. After that, seventeen groups of animals were tested with hole board apparatus for measuring anxiety behavior. For the statistical analysis, One-way analysis of variance (ANOVA and Dunnett's test were used. Results: Intra-CA1 injection of WIN55,212-2 (0.1, 0.5µg/mice did not modify anxiety-related behaviors in mice. But administration of AM251 (25 and 50ng/mice, histamine or ranitidine (5µg/mice induced anxiogenic-like response. Also, co-administration of WIN55, 212-2 with histaminergic agents, decreased the anxiogenic-like response of histamine, but not that of ranitidine. Co-administration of an ineffective dose of AM251 with histaminergic drugs did not alter the response induced by these drugs. In all the experiments, locomotor activity was not significantly changed. Conclusion: These results showed that there may be a partial interaction between the cannabinoidergic and the histaminergic systems of the dorsal hippocampus on anxiety-like behaviors.

  1. Interaction between Cannabinoidergic System and H2 Receptors in CA1 Region upon Anxiety-like Behaviors in Hole-Board Test

    Directory of Open Access Journals (Sweden)

    Zarrindast M.R

    2011-01-01

    Full Text Available Background and Objectives: Cannabinoids produce a wide array of effects on different species and interact with different neurotransmitter systems in the brain. In the present study, the effects of histaminergic and cannabinoidregic systems as well as their interactions on anxiety-related behaviors were examined on mice.Methods: In this study, at first mice were anesthetized with intra-peritoneal injection of ketamine hydrochloride and xylazine. They were then placed in a stereotaxic apparatus. Two stainless-steel cannuale were placed one mm above CA1 regions of the dorsal hippocampus. After that, seventeen groups of animals were tested with hole board apparatus for measuring anxiety behavior. For the statistical analysis, One-way analysis of variance (ANOVA and Dunnett's test were used.Results: Intra-CA1 injection of WIN55,212-2 (0.1, 0.5µg/mice did not modify anxiety-related behaviors in mice. But administration of AM251 (25 and 50ng/mice, histamine or ranitidine (5µg/mice induced anxiogenic-like response. Also, co-administration of WIN55, 212-2 with histaminergic agents, decreased the anxiogenic-like response of histamine, but not that of ranitidine. Co-administration of an ineffective dose of AM251 with histaminergic drugs did not alter the response induced by these drugs. In all the experiments, locomotor activity was not significantly changed. Conclusion: These results showed that there may be a partial interaction between the cannabinoidergic and the histaminergic systems of the dorsal hippocampus on anxiety-like behaviors.

  2. Draft ASME Boiler and Pressure Vessel Code Section III, Division 5, Section HB, Subsection B, Code Case for Alloy 617 and Background Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Julie Knibloe [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-08-01

    Alloy 617 is the leading candidate material for an intermediate heat exchanger for the very high temperature reactor. To evaluate the behavior of this material in the expected service conditions, strain controlled cyclic tests that include long hold times up to 240 minutes at maximum tensile strain were conducted at 850°C. In terms of the total number of cycles to failure, the fatigue resistance decreased when a hold time was added at peak tensile strain. Increases in the tensile hold duration degraded the creep fatigue resistance, at least to the investigated strain controlled hold time of up to 60 minutes at the 0.3% strain range and 240 minutes at the 1.0% strain range. The creep fatigue deformation mode is considered relative to the lack of saturation, or continually decreasing number of cycles to failure with increasing hold times. Additionally, preliminary values from the 850°C creep fatigue data are calculated for the creep fatigue damage diagram and have higher values of creep damage than those from tests at 950°C.

  3. Thyroid nodules, polymorphic variants in DNA repair and RET-related genes, and interaction with ionizing radiation exposure from nuclear tests in Kazakhstan

    Science.gov (United States)

    Sigurdson, Alice J.; Land, Charles E.; Bhatti, Parveen; Pineda, Marbin; Brenner, Alina; Carr, Zhanat; Gusev, Boris I.; Zhumadilov, Zhaxibay; Simon, Steven L.; Bouville, Andre; Rutter, Joni L.; Ron, Elaine; Struewing, Jeffery P.

    2010-01-01

    Risk factors for thyroid cancer remain largely unknown except for ionizing radiation exposure during childhood and a history of benign thyroid nodules. Because thyroid nodules are more common than thyroid cancers and are associated with thyroid cancer risk, we evaluated several polymorphisms potentially relevant to thyroid tumors and assessed interaction with ionizing radiation exposure to the thyroid gland. Thyroid nodules were detected in 1998 by ultrasound screening of 2997 persons who lived near the Semipalatinsk nuclear test site in Kazakhstan when they were children (1949-62). Cases with thyroid nodules (n=907) were frequency matched (1:1) to those without nodules by ethnicity (Kazakh or Russian), gender, and age at screening. Thyroid gland radiation doses were estimated from fallout deposition patterns, residence history, and diet. We analyzed 23 polymorphisms in 13 genes and assessed interaction with ionizing radiation exposure using likelihood ratio tests (LRT). Elevated thyroid nodule risks were associated with the minor alleles of RET S836S (rs1800862, p = 0.03) and GFRA1 -193C>G (rs not assigned, p = 0.05) and decreased risk with XRCC1 R194W (rs1799782, p-trend = 0.03) and TGFB1 T263I (rs1800472, p = 0.009). Similar patterns of association were observed for a small number of papillary thyroid cancers (n=25). Ionizing radiation exposure to the thyroid gland was associated with significantly increased risk of thyroid nodules (age and gender adjusted excess odds ratio/Gy = 0.30, 95% confidence interval 0.05-0.56), with evidence for interaction by genotype found for XRCC1 R194W (LRT p value = 0.02). Polymorphisms in RET signaling, DNA repair, and proliferation genes may be related to risk of thyroid nodules, consistent with some previous reports on thyroid cancer. Borderline support for gene-radiation interaction was found for a variant in XRCC1, a key base excision repair protein. Other pathways, such as genes in double strand break repair, apoptosis, and

  4. Development of austenitic stainless steel plate (316MN) for fast breeder reactors

    International Nuclear Information System (INIS)

    Nakazawa, Takanori; Abo, Hideo; Tanino, Mitsuru; Komatsu, Hazime.

    1989-01-01

    High creep-fatigue resistance is required for the structural materials for fast breeder reactors. As creep-fatigue life is closely related to creep-rupture ductility, the effects of C, N and Mo on creep-rupture properties were investigated with a view to improving the creep-fatigue resistance of stainless steel. Strengthening by the addition of C has a great adverse effect on rupture ductility, but N can strengthen the steel without decreasing rupture ductility. Strengthening by Mo decreases rupture ductility but this effect is small. The low-C-medium-N (0.01%C - 0.07%N) stainless steel 316 MN developed based on the findings described above exhibits only a small decrease in creep-rupture strength in long-time periods compared with the conventional 316 steel. This steel offers excellent rupture ductility and the 10,000-hour rupture strength which is about 1.2 times that of conventional steel. Moreover, this steel exhibits excellent properties in creep fatigue test. (author)

  5. Assessment of Bilateral Thoracic Loading on the Near-Side Occupant Due to Occupant-to-Occupant Interaction in Vehicle Crash Tests.

    Science.gov (United States)

    Sunnevång, Cecilia; Pipkorn, Bengt; Boström, Ola

    2015-01-01

    This study aims, by means of the WorldSID 50th percentile male, to evaluate thoracic loading and injury risk to the near-side occupant due to occupant-to-occupant interaction in combination with loading from an intruding structure. Nine vehicle crash tests were performed with a 50th percentile WorldSID male dummy in the near-side (adjacent to the intruding structure) seat and a THOR or ES2 dummy in the far-side (opposite the intruding structure) seat. The near-side seated WorldSID was equipped with 6 + 6 IR-Traccs (LH and RH) in the thorax/abdomen enabling measurement of bilateral deflection. To differentiate deflection caused by the intrusion, and the deflection caused by the neighboring occupant, time history curves were analyzed. The crash tests were performed with different modern vehicles, equipped with thorax side airbags and inflatable curtains, ranging from a compact car to a large sedan, and in different loading conditions such as car-to-car, barrier, and pole tests. Lateral delta V based on vehicle tunnel acceleration and maximum residual intrusion at occupant position were used as a measurement of crash severity to compare injury measurements. In the 9 vehicle crash tests, thoracic loading, induced by the intruding structure as well as from the far-side occupant, varied due to the size and structural performance of the car as well as the severity of the crash. Peak deflection on the thoracic outboard side occurred during the first 50 ms of the event. Between 70 to 150 ms loading induced by the neighboring occupant occurred and resulted in an inboard-side peak deflection and viscous criterion. In the tests where the target vehicle lateral delta V was below 30 km/h and intrusion less than 200 mm, deflections were low on both the outboard (20-40 mm) and inboard side (10-15 mm). At higher crash severities, delta V 35 km/h and above as well as intrusions larger than 350 mm, the inboard deflections (caused by interaction to the far-side occupant) were of the

  6. Reproducibility and Validity of the 6-Minute Walk Test Using the Gait Real-Time Analysis Interactive Lab in Patients with COPD and Healthy Elderly.

    Science.gov (United States)

    Liu, Wai-Yan; Meijer, Kenneth; Delbressine, Jeannet M; Willems, Paul J; Franssen, Frits M E; Wouters, Emiel F M; Spruit, Martijn A

    2016-01-01

    The 6-minute walk test (6MWT) in a regular hallway is commonly used to assess functional exercise capacity in patients with chronic obstructive pulmonary disease (COPD). However, treadmill walking might provide additional advantages over overground walking, especially if virtual reality and self-paced treadmill walking are combined. Therefore, this study aimed to assess the reproducibility and validity of the 6MWT using the Gait Real-time Analysis Interactive Lab (GRAIL) in patients with COPD and healthy elderly. Sixty-one patients with COPD and 48 healthy elderly performed two 6MWTs on the GRAIL. Patients performed two overground 6MWTs and healthy elderly performed one overground test. Differences between consecutive 6MWTs and the test conditions (GRAIL vs. overground) were analysed. Patients walked further in the second overground test (24.8 m, 95% CI 15.2-34.4 m, pelderly improved their second GRAIL test (49.6 m, 95% CI 37.0-62.3 m). The GRAIL 6MWT was reproducible (intra-class coefficients = 0.65-0.80). The best GRAIL 6-minute walk distance (6MWD) in patients was shorter than the best overground 6MWD (-27.3 ± 49.1 m, pelderly walked further on the GRAIL than in the overground condition (23.6 ± 41.4 m, pelderly. The GRAIL 6MWD seems to be more comparable to the 6MWDs assessed overground than previous studies on treadmills have reported. Furthermore, good construct validity and reproducibility were established in assessing the 6MWD using the GRAIL in patients with COPD and healthy elderly.

  7. A CRITICAL THOUGHT OF INSTRUCTIONAL STRATEGY: DEVELOPING ANALYTICAL CAPABILITY OF AUTOMOTIVE STUDENTS BY MANAGING MORE APPLICABLE MOVIE FRAGMENTS, POWER POINT, AND INTERACTIVE TEST

    Directory of Open Access Journals (Sweden)

    Agus Riyanto -

    2017-02-01

    Full Text Available What most sensed about Technical High School (known as SMK students is their lack of analytical capability. As their nature of academic orientation is aimed at job fullfillment, the students are enhanced to follow Standard Operational Procedure (SOP without questioning why such SOP should be followed. As for automotive students, they simply following the steps of doing things related to any activities of repairing car and other mechanical work required just because the job will be done well when the procedure completed.  This kind of mentality “following order or SOP” fits to those who only want to be workers not the men who take higher responsibilities. The progress of automotive technology demand on understanding the concept of how some system used in a car. Failure to comprehend to concept will jeopardize the performance of a car. At the same time, the progress of automotive technology is also propelled by the progress of information technology which provides more open resources that can be used to promote the quality of instuctional process.  Realizing that having analysis compentence is terribly important to run higher responsibilites and continuing education to a university, automotive students need to learn how to analyze. To promote this, teacher can use some automotive movies or animations and then chop them into many fragments related to instructional objectives. The way how the teachers arrange and present the fragments can be combined into power point and ended up with an interactive test with different model of methods, strategies, or techniques. Movies, movie cutter application, interactive test Creator ,  paint into fragments can be obtained freely from the internet. The using of movie fragments integrated into power point, arrange the fragment into various strategies, ended up with interactive test will likely focus the students into more realistic understanding toward the concept taught in the classroom. In return the

  8. Environmental effect of S02-bearing atmosphere on the creep fatigue failure of aluminide-coated MM-002 nickel-base superalloy at 870°C

    CSIR Research Space (South Africa)

    Aghion, E

    1995-04-15

    Full Text Available High-temperature low-cycle fatigue (HTLCF) failure mechanisms of aluminide-coated MAR-M002 nickel-base superalloy in air, argon and Ar+5% SO2 atmospheres were investigated at 870°C. The loading conditions were constant and consisted of creep tension...

  9. Aerodynamic-thermomechanical coupling and creep fatigue damage prediction during a cold start-up of a high pressure rotor. Aerodynamic investigation

    Energy Technology Data Exchange (ETDEWEB)

    Dejean, F.

    1995-12-01

    The purpose of this paper is an aerodynamic simulation of the bucket root and diaphragm packing leakage flow within an impulse steam turbine HP cylinder. Calculations were undertaken in order to accurately compute both the steam temperature and steam-metal heat transfer coefficients. In order to perform this study, a compressible and turbulent finite elements Navier-Stokes code was used. Inlet and exit conditions were computed using an axisymmetrical through flow computer code and a thermal boundary layer modelling, based on classical wall function laws, was used in order to compute heat transfer coefficients. This computational study has underlined the capability of our computer codes to deal with a complex industrial problem and thermal wall boundary conditions were accurately obtained. Moreover, a complex leakage flow problem, with many recirculation zones was solves and interesting results are available. (author) 9 refs.

  10. Creep-fatigue deformation behaviour of OFHC-copper and CuCrZr alloy with different heat treatments and with and without neutron irradiation

    DEFF Research Database (Denmark)

    Singh, B.N.; Li, M.; Stubbins, J.F.

    2005-01-01

    results of these investigations are presented andtheir implications are briefly discussed in the present report. The central conclusion emerging from the present work is that the application of holdtime generally reduces the number of cycles to failure. The largest reduction was found to be in the caseof...... causes a substantial decrease in the number of cycles to failure at all holdtimes investigated. The increase in the yield strength due to neutron irradiation at 333 K, on the other hand, causes anincrease in the number of cycles to failure. The irradiation at 573 K to a dose level of 0.2-0.3 dpa does...

  11. The Mann-Kendall test: the need to consider the interaction between serial correlation and trend - doi: 10.4025/actasciagron.v35i4.16006

    Directory of Open Access Journals (Sweden)

    Gabriel Constantino Blain

    2013-05-01

    Full Text Available Pre-whitening approaches have been widely used to remove the influence of serial correlations on the Mann-Kendall trend test (MK_prew. However, previous studies indicate that this procedure may lead to a false reduction of the significance of a trend. An alternative approach (MK_interact has been proposed to improve the assessment of the significance of a trend in auto-correlated data. Therefore, the present study compared the performance of the MK_prew and MK_interact for detecting trends in auto-correlated series. Sets of Monte Carlo experiments were carried out to evaluate the occurrence of type I and II errors obtained from both approaches. The analyses were also based on 10-day values of the difference between precipitation and potential evapotranspiration (P-EP obtained from the location of Campinas, State of São Paulo, Brazil. The results found in this study allow us to conclude that the MK_interac outperformed the MK_prew in correctly identifying the significance of trends and that, concerning agricultural interests, the decreasing trend described by the MK_interac during the beginning of the crop growing seasons may reveal an unfavorable temporal distribution of the P-EP values.

  12. Testing the feasibility of an interactive learning styles measure for U.S. Latino adults with type 2 diabetes and low literacy.

    Science.gov (United States)

    Carbone, Elena T; Lennon, Karen M; Torres, M Idalí; Rosal, Milagros C

    This study designed and piloted an interactive measure to assess learning preferences of Latinos in the United States with diabetes and limited literacy. The measure utilized interactive learning activities to represent four learning styles: visual (seeing), kinesthetic (doing), affective (feeling/sensing), and cognitive (thinking), targeting four diabetes self-management behaviors: choosing healthy foods; understanding portion sizes; distinguishing foods to eat often/sometimes/rarely; and limiting fat. Quantitative data were collected using the Spanish Short Test of Functional Health Literacy in Adults (S-TOFHLA). Individual, structured cognitive interview questions asked participants to identify learning activities that most reflected their own experience with diabetes. Participant observations provided additional qualitative data. Ten Spanish-speaking adults with type 2 diabetes and limited literacy participated in two randomly selected target behaviors and identified easiest and most difficult to understand learning activities. S-TOFHLA scores ranged from 0 to 21 points (mean 7.0) and identified eight participants with inadequate and two with marginal health literacy. Easiest to understand tasks were kinesthetic, most difficult to understand tasks were cognitive. This is one of the first known studies of its kind and offers insight for measuring learning styles of Latinos with diabetes and low health literacy.

  13. Confirmation test on the dynamic interaction between a model reactor-building foundation and ground in the Sendai Nuclear Power Station

    International Nuclear Information System (INIS)

    Umezu, Hideo; Kisaki, Noboru; Shiota, Mutsumi

    1982-01-01

    On the site of unit 2 (planned) in the Sendai Nuclear Power Station, a model reactor-building foundation of reinforced concrete with diameter of 12 m and height of 5 m was installed. With a vibration generator, its forced vibration tests were carried out in October to December, 1980. Valuable data were able to be obtained on the dynamic interaction between the model foundation and the ground, and also the outlook for the application of theories in hard base rock was obtained. (1) The resonance frequency of the model foundation in horizontal vibration was 35 Hz in both NS and EW directions. (2) Remarkable difference was not observed in the horizontal vibration behavior between NS and EW directions, so that there is not anisotropy in the ground. (3) The model foundation was deformed nearly as a rigid body. (J.P.N.)

  14. Set-Based Joint Test of Interaction Between SNPs in the VEGF Pathway and Exogenous Estrogen Finds Association With Age-Related Macular Degeneration

    Science.gov (United States)

    Courtenay, Monique D.; Cade, William H.; Schwartz, Stephen G.; Kovach, Jaclyn L.; Agarwal, Anita; Wang, Gaofeng; Haines, Jonathan L.; Pericak-Vance, Margaret A.; Scott, William K.

    2014-01-01

    Purpose. Age-related macular degeneration (AMD) is the leading cause of irreversible visual loss in developed countries. Its etiology includes genetic and environmental factors. Although VEGFA variants are associated with AMD, the joint action of variants within the VEGF pathway and their interaction with nongenetic factors have not been investigated. Methods. Affymetrix 6.0 chipsets were used to genotype 668,238 single nucleotide polymorphisms (SNPs) in 1207 AMD cases and 686 controls. Environmental exposures were collected by questionnaire. A set-based test was conducted using the χ2 statistic at each SNP derived from Kraft's two degree of freedom (2df) joint test. Pathway- and gene-based test statistics were calculated as the mean of all independent SNP statistics. Phenotype labels were permuted 10,000 times to generate an empirical P value. Results. While a main effect of the VEGF pathway was not identified, the pathway was associated with neovascular AMD in women when accounting for birth control pill (BCP) use (P = 0.017). Analysis of VEGF's subpathways showed that SNPs in the proliferation subpathway were associated with neovascular AMD (P = 0.029) when accounting for BCP use. Nominally significant genes within this subpathway were also observed. Stratification by BCP use revealed novel significant genetic effects in women who had taken BCPs. Conclusions. These results illustrate that some AMD genetic risk factors may be revealed only when complex relationships among risk factors are considered. This shows the utility of exploring pathways of previously associated genes to find novel effects. It also demonstrates the importance of incorporating environmental exposures in tests of genetic association at the SNP, gene, or pathway level. PMID:25015356

  15. The changing and its interaction of determining serum gastrin levels and helicobacter pylori test during chronic atrophic gastritis into gastric cancer

    International Nuclear Information System (INIS)

    Jing Weijuan; Yang Yongqing

    2009-01-01

    Objective: To study the changing and its interaction of determining serum gastrin levels and Helicobacter pylori test during chronic atrophic gastritis into gastric cancer. Methods: RIA and 13 C-urea breath test ( 13 C-UBT) determined the Gs levels and Hp infection rate in 63 rate cases (first visit) patients, 48 cases (after one year return visit) patients, 35 cases (after three year return visit) patients and 30 cases (after five years return visit) patients with CAG 90 cases patients with gastric cancer (and different position) and 61 cases normal controls. They all were done study compared. Results: Serum Gs levels in 63 cases (first visit) patients, 48 cases (after one year return visit) patients, 35 cases (after three year return visit) patients and 30 cases (after five years return visit) patient with CAG were significantly higher (t=4.716, 5.218, 5.624, 6.179, 6.5772, all P 0.05). Serum Gs levels in 90 cases with gastric cancer (and different position) was significantly higher (t=4.221, P<0.05; t=4.436, P<0.01) than 61 cases normal controls and the highest serum Gs level was found in cancer of cardia and fundus. And Hp infection rate was 88.8%. Conclusion: The early diagnosis on gastric cancer was very important by determining serum Gs and Hp infection rate. (authors)

  16. A task-specific interactive game-based virtual reality rehabilitation system for patients with stroke: a usability test and two clinical experiments.

    Science.gov (United States)

    Shin, Joon-Ho; Ryu, Hokyoung; Jang, Seong Ho

    2014-03-06

    Virtual reality (VR) is not commonly used in clinical rehabilitation, and commercial VR gaming systems may have mixed effects in patients with stroke. Therefore, we developed RehabMaster™, a task-specific interactive game-based VR system for post-stroke rehabilitation of the upper extremities, and assessed its usability and clinical efficacy. A participatory design and usability tests were carried out for development of RehabMaster with representative user groups. Two clinical trials were then performed. The first was an observational study in which seven patients with chronic stroke received 30 minutes of RehabMaster intervention per day for two weeks. The second was a randomised controlled trial of 16 patients with acute or subacute stroke who received 10 sessions of conventional occupational therapy only (OT-only group) or conventional occupational therapy plus 20 minutes of RehabMaster intervention (RehabMaster + OT group). The Fugl-Meyer Assessment score (FMA), modified Barthel Index (MBI), adverse effects, and drop-out rate were recorded. The requirements of a VR system for stroke rehabilitation were established and incorporated into RehabMaster. The reported advantages from the usability tests were improved attention, the immersive flow experience, and individualised intervention. The first clinical trial showed that the RehabMaster intervention improved the FMA (P = .03) and MBI (P = .04) across evaluation times. The second trial revealed that the addition of RehabMaster intervention tended to enhance the improvement in the FMA (P = .07) but did not affect the improvement in the MBI. One patient with chronic stroke left the trial, and no adverse effects were reported. The RehabMaster is a feasible and safe VR system for enhancing upper extremity function in patients with stroke.

  17. Noise and noise disturbances from wind power plants - Tests with interactive control of sound parameters for more comfortable and less perceptible sounds

    International Nuclear Information System (INIS)

    Persson-Waye, K.; Oehrstroem, E.; Bjoerkman, M.; Agge, A.

    2001-12-01

    In experimental pilot studies, a methodology has been worked out for interactively varying sound parameters in wind power plants. In the tests, 24 persons varied the center frequency of different band-widths, the frequency of a sinus-tone and the amplitude-modulation of a sinus-tone in order to create as comfortable a sound as possible. The variations build on the noise from the two wind turbines Bonus and Wind World. The variations were performed with a constant dba level. The results showed that the majority preferred a low-frequency tone (94 Hz and 115 Hz for Wind World and Bonus, respectively). The mean of the most comfortable amplitude-modulation varied between 18 and 22 Hz, depending on the ground frequency. The mean of the center-frequency for the different band-widths varied from 785 to 1104 Hz. In order to study the influence of the wind velocity on the acoustic character of the noise, a long-time measurement program has been performed. A remotely controlled system has been developed, where wind velocity, wind direction, temperature and humidity are registered simultaneously with the noise. Long-time registrations have been performed for four different wing turbines

  18. A Measurement of the muon neutrino charged current quasielastic interaction and a test of Lorentz violation with the MiniBooNE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Katori, Teppei [Indiana Univ., Bloomington, IN (United States)

    2008-12-01

    The Mini-Booster neutrino experiment (MiniBooNE) at Fermi National Accelerator Laboratory (Fermilab) is designed to search for vμ → ve appearance neutrino oscillations. Muon neutrino charged-current quasi-elastic (CCQE) interactions (vμ + n → μ + p) make up roughly 40% of our data sample, and it is used to constrain the background and cross sections for the oscillation analysis. Using high-statistics MiniBooNE CCQE data, the muon-neutrino CCQE cross section is measured. The nuclear model is tuned precisely using the MiniBooNE data. The measured total cross section is σ = (1.058 ± 0.003 (stat) ± 0.111 (syst)) x 10-38 cm2 at the MiniBooNE muon neutrino beam energy (700-800 MeV). ve appearance candidate data is also used to search for Lorentz violation. Lorentz symmetry is one of the most fundamental symmetries in modern physics. Neutrino oscillations offer a new method to test it. We found that the MiniBooNE result is not well-described using Lorentz violation, however further investigation is required for a more conclusive result.

  19. Adolescent Internet addiction: testing the association between self-esteem, the perception of Internet attributes, and preference for online social interactions.

    Science.gov (United States)

    Fioravanti, Giulia; Dèttore, Davide; Casale, Silvia

    2012-06-01

    There is a general consensus that Internet addiction (IA) is mainly related to social aspects of the Web, especially among adolescents. The empirical link between poor social skills and IA is well documented; however, theoretical explanations for this relationship are less developed. One possibility is that people with poor social skills are especially prone to develop a preference for online social interaction (POSI), which, in turn, predicts problematic usage. This hypothesis has been tested for loneliness and social anxiety, but not for self-esteem (SE; one of the main antecedents of IA). Furthermore, the mediating role of the perceived relevance of some Internet features (e.g., anonymity) in the relationship between SE and POSI has never been investigated. A cross-sectional study was conducted with 257 adolescents. Using mediation analyses, we found evidence among females for the mediating role of (a) POSI in the relationship between SE and IA, and (b) the subjective relevance of some Internet features in the association between SE and POSI. No significant effects were found for males.

  20. Sensitivity of palaeo-ice-stream retreat patterns to ice-ocean interactions and topography: a test of the marine ice sheet instability hypothesis

    Science.gov (United States)

    Jamieson, S.; Vieli, A.; Livingstone, S. J.; O'Cofaigh, C.; Stokes, C. R.; Hillenbrand, C.

    2011-12-01

    The aim is to understand the long-term controls on marine ice stream retreat. Short-term observations combined with modelling are helping decipher the controls driving contemporary mass loss via dynamic thinning and grounding-line retreat. However, ice-stream response times are likely to be longer than the timescales for which contemporary observations are available. We therefore focus on century to millenial timescales by investigating the retreat of Marguerite Bay palaeo-ice stream in Antarctica after the LGM. Our approach is to use high-resolution mapping of glacial landforms on the sea floor to constrain a numerical ice stream model. Mapped positions of grounding-zone wedges indicate that the palaeo-ice stream paused multiple times during its rapid retreat over a bed that deepens inland. The geomorphic record not only questions the marine ice sheet instability hypothesis but also provides geometrical and dynamical constraints for retreat experiments using numerical ice stream models. To understand the controls on the retreat pattern in Marguerite Bay, we test the sensitivity of the ice stream to a range of forcing regimes using a 1-dimensional numerical flow-line model that incorporates basal, lateral and longitudinal stresses and a self-refining grid scheme. Ice-ocean interactions are incorporated via a fixed-length ice shelf, the inclusion of an ice-ocean boundary condition and the calculation of ocean-driven melt. We test modelled retreat sensitivity to a range of external forcing patterns including sea-level, temperature, accumulation and ocean-driven melt. In addition, the importance of the topographic setting of the ice drainage basin is also examined. We find that the modelled ice stream naturally re-creates the pauses observed in the geomorphic record and that the pattern of palaeo-grounding-line retreat in Marguerite Bay can only be achieved within the chronological timeframe by including ocean-driven melt. Sensitivity tests indicate that the

  1. Testing the time-scale dependence of delayed interactions: A heat wave during the egg stage shapes how a pesticide interacts with a successive heat wave in the larval stage.

    Science.gov (United States)

    Janssens, Lizanne; Tüzün, Nedim; Stoks, Robby

    2017-11-01

    Under global change organisms are exposed to multiple, potentially interacting stressors. Especially interactions between successive stressors are poorly understood and recently suggested to depend on their timing of exposure. We particularly need studies assessing the impact of exposure to relevant stressors at various life stages and how these interact. We investigated the single and combined impacts of a heat wave (mild [25 °C] and extreme [30 °C]) during the egg stage, followed by successive exposure to esfenvalerate (ESF) and a heat wave during the larval stage in damselflies. Each stressor caused mortality. The egg heat wave and larval ESF exposure had delayed effects on survival, growth and lipid peroxidation (MDA). This resulted in deviations from the prediction that stressors separated by a long time interval would not interact: the egg heat wave modulated the interaction between the stressors in the larval stage. Firstly, ESF caused delayed mortality only in larvae that had been exposed to the extreme egg heat wave and this strongly depended upon the larval heat wave treatment. Secondly, ESF only increased MDA in larvae not exposed to the egg heat wave. We found little support for the prediction that when there is limited time between stressors, synergistic interactions should occur. The intermediate ESF concentration only caused delayed mortality when combined with the larval heat wave, and the lowest ESF concentrations only increased oxidative damage when followed by the mild larval heat wave. Survival selection mitigated the interaction patterns between successive stressors that are individually lethal, and therefore should be included in a predictive framework for the time-scale dependence of the outcome of multistressor studies with pollutants. The egg heat wave shaping the interaction pattern between successive pesticide exposure and a larval heat wave highlights the connectivity between the concepts of 'heat-induced pesticide sensitivity' and

  2. Analysis of 440 GeV proton beam-matter interaction experiments at the High Radiation Materials test facility at CERN

    Science.gov (United States)

    Burkart, F.; Schmidt, R.; Raginel, V.; Wollmann, D.; Tahir, N. A.; Shutov, A.; Piriz, A. R.

    2015-08-01

    In a previous paper [Schmidt et al., Phys. Plasmas 21, 080701 (2014)], we presented the first results on beam-matter interaction experiments that were carried out at the High Radiation Materials test facility at CERN. In these experiments, extended cylindrical targets of solid copper were irradiated with beam of 440 GeV protons delivered by the Super Proton Synchrotron (SPS). The beam comprised of a large number of high intensity proton bunches, each bunch having a length of 0.5 ns with a 50 ns gap between two neighboring bunches, while the length of this entire bunch train was about 7 μs. These experiments established the existence of the hydrodynamic tunneling phenomenon the first time. Detailed numerical simulations of these experiments were also carried out which were reported in detail in another paper [Tahir et al., Phys. Rev. E 90, 063112 (2014)]. Excellent agreement was found between the experimental measurements and the simulation results that validate our previous simulations done using the Large Hadron Collider (LHC) beam of 7 TeV protons [Tahir et al., Phys. Rev. Spec. Top.--Accel. Beams 15, 051003 (2012)]. According to these simulations, the range of the full LHC proton beam and the hadronic shower can be increased by more than an order of magnitude due to the hydrodynamic tunneling, compared to that of a single proton. This effect is of considerable importance for the design of machine protection system for hadron accelerators such as SPS, LHC, and Future Circular Collider. Recently, using metal cutting technology, the targets used in these experiments have been dissected into finer pieces for visual and microscopic inspection in order to establish the precise penetration depth of the protons and the corresponding hadronic shower. This, we believe will be helpful in studying the very important phenomenon of hydrodynamic tunneling in a more quantitative manner. The details of this experimental work together with a comparison with the numerical

  3. Design, characterization, teratogenicity testing, antibacterial, antifungal and DNA interaction of few high spin Fe(II) Schiff base amino acid complexes

    Science.gov (United States)

    Abdel-Rahman, Laila H.; El-Khatib, Rafat M.; Nassr, Lobna A. E.; Abu-Dief, Ahmed M.; Lashin, Fakhr El-Din

    2013-07-01

    In this study, new Fe(II) Schiff base amino acid chelates derived from the condensation of o-hydroxynaphthaldehyde with L-alanine, L-phenylalanine, L-aspartic acid, L-histidine and L-arginine were synthesized and characterized via elemental, thermogravimetric analysis, molar conductance, IR, electronic, mass spectra and magnetic moment measurements. The stoichiometry and the stability constants of the complexes were determined spectrophotometrically. Correlation of all spectroscopic data suggested that Schiff bases ligands exhibited tridentate with ONO sites coordinating to the metal ions via protonated phenolic-OH, azomethine-N and carboxylate-O with the general formulae [Fe(HL)2]·nH2O. But in case of L-histidine, the ligand acts as tetradentate via deprotonated phenolic-OH, azomethine-N, carboxylate-O and N-imidazole ring ([FeL(H2O)2]·2H2O), where HL = mono anion and L = dianion of the ligand. The structure of the prepared complexes is suggested to be octahedral. The prepared complexes were tested for their teratogenicity on chick embryos and found to be safe until a concentration of 100 μg/egg with full embryos formation. Moreover, the interaction between CT-DNA and the investigated complexes were followed by spectrophotometric and viscosity measurements. It was found that, the prepared complexes bind to DNA via classical intercalative mode and showed a different DNA activity with the sequence: nhi > nari > nali > nasi > nphali. Furthermore, the free ligands and their complexes are screened for their in vitro antibacterial and antifungal activity against three types of bacteria, Escherichia coli, Pseudomonas aeruginosa and Bacillus cereus and three types of anti fungal cultures, Penicillium purpurogenium, Aspergillus flavus and Trichotheium rosium in order to assess their antimicrobial potential. The results show that the metal complexes are more reactive with respect to their corresponding Schiff base amino acid ligands.

  4. Friction Surfacing In Steel 304

    OpenAIRE

    S. Godwin Barnabas; Anantharam; Shyam sundar; B.S.Aravind T.Prabhu

    2016-01-01

    Surface engineering deals with the surface of the solid matter and it is sub-discipline of The surface phase of a solid interacts with the surrounding environment. This interaction can degrade the surface phase over time, may result in loss of material from its surface. Environmental degradation of the surface phase over time can be caused by wear, corrosion, creep, fatigue loads, shear loads, tensile loads, cutting forces or when exposed to higher temperature. Wear can be minimiz...

  5. Technical issues of RAFMs for the fabrication of ITER Test Blanket Module

    International Nuclear Information System (INIS)

    Tanigawa, Hiroyasu; Hirose, Takanori; Shiba, Kiyoyuki

    2007-01-01

    remaining to be examined to assure its applicability even under the most severe operation scenario. ITER will be operated in the pulsed mode with cycles up to 30,000, and severe plasma disruptions are expected to occur 100 times per year, suggesting that the structural materials will experience fatigue and/or creep fatigue loading. The fatigue softening would be an issue to degrade the strength of RAFMs during the ITER operation. Another issue would be the effects of Ta. Ta was added to all RAFMs to improve fracture toughness and creep strength, but recent work found it tends to form inclusions and causes toughness inhomogeneity, and increases the possibility of hot cracking during welding. To overcome these issues, it is essential to obtain a good understanding of the detailed mechanical properties and design TBM carefully based on that. (orig.)

  6. Spatiotemporal gait characteristics in patients with COPD during the Gait Real-time Analysis Interactive Lab-based 6-minute walk test.

    Science.gov (United States)

    Liu, Wai-Yan; Spruit, Martijn A; Delbressine, Jeannet M; Willems, Paul J; Franssen, Frits M E; Wouters, Emiel F M; Meijer, Kenneth

    2017-01-01

    Overground gait assessment is limited by the analysis of multiple strides or both spatiotemporal gait characteristics, while fixed speed treadmill walking restricts natural gait speed variations. The Gait Real-time Analysis Interactive Lab (GRAIL)-based 6-minute walk test (6MWT) enables 3D motion analysis and self-paced treadmill walking, and could provide insight in gait alterations in patients with chronic obstructive pulmonary disease (COPD). The aim of this study is to compare spatiotemporal gait characteristics between patients with COPD and healthy elderly during the GRAIL-based 6MWT. Eighty COPD patients (60% male; 62±7 years; FEV1:56±19% predicted) and 38 healthy elderly (63% male; 62±6 years; FEV1:119±17% predicted) performed two GRAIL-based 6MWTs. Mean differences and coefficient of variation of spatiotemporal gait characteristics were calculated using the trial with the largest walk distance. Sub-analyses were conducted to account for walking speed differences between groups, and muscle strength and COPD severity within the patient group. COPD patients showed increased temporal gait characteristics, decreased stride and step lengths, and increased gait variability compared to healthy elderly (pgait characteristics, while COPD severity is associated with stride time (left MD:-0.02s, CI:-0.04-0.01, p = 0.003; right MD:-0.02s, CI:-0.04-0.01, p = 0.003). COPD patients performed the GRAIL-based 6MWT differently compared to healthy elderly. Further research should use other variability measures to investigate gait characteristics in COPD, to assess subtle alterations in gait and to enable development of rehabilitation strategies to improve gait, and possibly balance and fall risk in COPD. Other lower limb muscle groups should be considered when investigating gait alterations in COPD. COPD patients have different gait characteristics compared to healthy elderly. Independent of walking speed, COPD patients demonstrate increased stride length variability

  7. SNP interaction pattern identifier (SIPI)

    DEFF Research Database (Denmark)

    Lin, Hui Yi; Chen, Dung Tsa; Huang, Po Yu

    2017-01-01

    Motivation: Testing SNP-SNP interactions is considered as a key for overcoming bottlenecks of genetic association studies. However, related statistical methods for testing SNP-SNP interactions are underdeveloped. Results: We propose the SNP Interaction Pattern Identifier (SIPI), which tests 45 bi...

  8. Laboratory creep and mechanical tests on salt data report (1975-1996): Waste Isolation Pilot Plant (WIPP) thermal/structural interactions program

    Energy Technology Data Exchange (ETDEWEB)

    Mellegard, K.D. [RE/SPEC Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

    1997-02-01

    The Waste Isolation Pilot Plant (WIPP), a facility located in a bedded salt formation in Carlsbad, New Mexico, is being used by the U.S. Department of Energy to demonstrate the technology for safe handling and disposal of transuranic wastes produced by defense activities in the United States. In support of that demonstration, mechanical tests on salt were conducted in the laboratory to characterize material behavior at the stresses and temperatures expected for a nuclear waste repository. Many of those laboratory test programs have been carried out in the RE/SPEC Inc. rock mechanics laboratory in Rapid City, South Dakota; the first program being authorized in 1975 followed by additional testing programs that continue to the present. All of the WIPP laboratory data generated on salt at RE/SPEC Inc. over the last 20 years is presented in this data report. A variety of test procedures were used in performance of the work including quasi-static triaxial compression tests, constant stress (creep) tests, damage recovery tests, and multiaxial creep tests. The detailed data is presented in individual plots for each specimen tested. Typically, the controlled test conditions applied to each specimen are presented in a plot followed by additional plots of the measured specimen response. Extensive tables are included to summarize the tests that were performed. Both the tables and the plots contain cross-references to the technical reports where the data were originally reported. Also included are general descriptions of laboratory facilities, equipment, and procedures used to perform the work.

  9. Versão brasileira do Social Interaction Self-Statement Test (SISST: tradução e adaptação transcultural Brazilian version of the Social Interaction Self-Statement Test (SISST: translation and cross-cultural adaptation

    Directory of Open Access Journals (Sweden)

    Adriana Cardoso de Oliveira e Silva

    2010-01-01

    Full Text Available CONTEXTO: O Social Interaction Self-Statement Test (SISST apresenta como proposta avaliar respostas cognitivas em adultos que referem dificuldades heterossociais. Sua adaptação transcultural apresenta-se como primeiro passo para futuras comparações relativas ao construto medido pelo instrumento em diferentes amostras. OBJETIVO: Adaptação semântica do SISST para o português brasileiro. MÉTODOS: Processo realizado por meio de duas traduções e retrotraduções, elaboradas por avaliadores independentes e sem conhecimentos prévios da escala a ser traduzida. Elaboração de versão sintética realizada conjuntamente por dois diferentes especialistas, bilíngues, em saúde mental. RESULTADOS: São apresentadas as quatro etapas do processo. A utilização de duas traduções e retrotraduções permitiu uma discussão mais ampla para construção da versão sintética. A participação de especialistas em saúde mental colaborou para a adequação dos termos utilizados em relação ao construto medido. A aplicação experimental ofereceu maior segurança ao processo de equivalência semântica. CONCLUSÃO: Por meio da metodologia utilizada, foi possível elaborar uma versão do SISST para o português brasileiro.BACKGROUND: The Social Interaction Self-Statement Test (SISST proposes to evaluate cognitive responses in adults who reported heterosocial difficulties. Its cross-cultural adaptation is the first stage for future comparisons on the construct measured by the instrument in different populations. OBJECTIVE: Semantic adaptation of the SISST for Brazilian Portuguese. METHODS: Process consisted of two translations and back-translations, performed by independent evaluators without any prior knowledge of the scale to be translated. Development of synthetic version was conducted jointly by two different expertises in mental health. RESULTS: The four stages of the process were presented. The use of two translations and back-translations allowed

  10. High temperature strength of Hastelloy XR under biaxial stress states

    International Nuclear Information System (INIS)

    Muto, Yasushi; Hada, Kazuhiko; Koikegami, Hajime; Ohno, Nobutada.

    1991-01-01

    Biaxial(tension/torsion) creep and creep-fatigue tests were conducted on Hastelloy XR at 950degC in air. Hastelloy XR is a nickel base solution-annealed heat resistant alloy. Thin-walled tubular test specimens were employed. As results of the creep tests, the von Mises' flow rule was revealed to be applicable very well. Under the torsion load, sufficient growth of voids was necessary to initiate the fracture and this resulted in longer life time compared with that under the tension load. Only a few number of small voids could be observed and very long life times were attained under the compression load. The creep-fatigue tests revealed that superposition of constant torsion load on a cyclic axial load reduced the cycles to failure significantly and the amount of reduction was consistent with the prediction by the linear life fraction rule. (author)

  11. Diagnostics improvement in the ABC facility and preliminary tests on laser interaction with light-atom clusters and p+{sup 11}B targets

    Energy Technology Data Exchange (ETDEWEB)

    Consoli, Fabrizio, E-mail: fabrizio.consoli@enea.it [Associazione Euratom - ENEA sulla Fusione, via E. Fermi 45, CP 65-00044 Frascati, Rome (Italy); De Angelis, Riccardo; Andreoli, Pierluigi; Cristofari, Giuseppe; Di Giorgio, Giorgio [Associazione Euratom - ENEA sulla Fusione, via E. Fermi 45, CP 65-00044 Frascati, Rome (Italy); Bonasera, Aldo [INFN - LNS, via S. Sofia 62, I-95123 Catania (Italy); Cyclotron Institute, Texas A and M University, College Station, TX, 77843 (United States); Barbui, Marina [Cyclotron Institute, Texas A and M University, College Station, TX, 77843 (United States); Mazzocco, Marco [Dipartimento di Fisica G. Galilei, Università degli Studi di Padova, via F. Marzolo 8, I-35131 Padova (Italy); Bang, Woosuk; Dyer, Gilliss; Quevedo, Hernan [Texas Center for High Intensity Laser Science, University of Texas at Austin, Austin 78712, TX (United States); Hagel, Kris; Schmidt, Katarzyna [Cyclotron Institute, Texas A and M University, College Station, TX, 77843 (United States); Gaul, Erhard; Borger, Ted; Bernstein, Aaron; Martinez, Mikael; Donovan, Michael [Texas Center for High Intensity Laser Science, University of Texas at Austin, Austin 78712, TX (United States); Barbarino, Matteo [Cyclotron Institute, Texas A and M University, College Station, TX, 77843 (United States); Kimura, Sachie [INFN - LNS, via S. Sofia 62, I-95123 Catania (Italy); and others

    2013-08-21

    The diagnostics of particle flows in Inertial Confinement Fusion experiments is a delicate issue, due to the fast timescales and to the strong radiative electromagnetic contributions. This makes the discrimination of the different particles produced by the laser–plasma interaction not trivial, and requires the use of several diagnostic techniques. We describe here the diagnostics improvement in the ABC facility. They will provide more detailed analysis of microwave fields and particles originating from the interaction of laser with targets foreseen for future experiments.

  12. Diagnostics improvement in the ABC facility and preliminary tests on laser interaction with light-atom clusters and p+11B targets

    International Nuclear Information System (INIS)

    Consoli, Fabrizio; De Angelis, Riccardo; Andreoli, Pierluigi; Cristofari, Giuseppe; Di Giorgio, Giorgio; Bonasera, Aldo; Barbui, Marina; Mazzocco, Marco; Bang, Woosuk; Dyer, Gilliss; Quevedo, Hernan; Hagel, Kris; Schmidt, Katarzyna; Gaul, Erhard; Borger, Ted; Bernstein, Aaron; Martinez, Mikael; Donovan, Michael; Barbarino, Matteo; Kimura, Sachie

    2013-01-01

    The diagnostics of particle flows in Inertial Confinement Fusion experiments is a delicate issue, due to the fast timescales and to the strong radiative electromagnetic contributions. This makes the discrimination of the different particles produced by the laser–plasma interaction not trivial, and requires the use of several diagnostic techniques. We describe here the diagnostics improvement in the ABC facility. They will provide more detailed analysis of microwave fields and particles originating from the interaction of laser with targets foreseen for future experiments

  13. Online Games as a Component of School Textbooks: A Test Predicting the Diffusion of Interactive Online Games Designed for the Textbook Reformation in South Korea

    Science.gov (United States)

    Kim, Do Kyun; Dinu, Lucian F.; Chung, Wonjon

    2013-01-01

    Currently, the South Korean government is in the process of transforming school textbooks from a paper-based platform to a computer-based digital platform. Along with this effort, interactive online educational games (edu-games) have been examined as a potential component of the digital textbooks. Based on the theory of diffusion of innovations,…

  14. Inverse modeling of cloud-aerosol interactions — Part 2: Sensitivity tests on liquid phase clouds using a Markov Chain Monte Carlo based simulation approach

    NARCIS (Netherlands)

    Partridge, D.G.; Vrugt, J.A.; Tunved, P.; Ekman, A.M.L.; Struthers, H.; Sorooshian, A.

    2012-01-01

    This paper presents a novel approach to investigate cloud-aerosol interactions by coupling a Markov Chain Monte Carlo (MCMC) algorithm to a pseudo-adiabatic cloud parcel model. Despite the number of numerical cloud-aerosol sensitivity studies previously conducted few have used statistical analysis

  15. Lifetime assessment of thick-walled components made of nickel-base alloys under near-service loading conditions

    International Nuclear Information System (INIS)

    Hueggenberg, Daniel

    2015-01-01

    Until 2050 the renewable energies should provide 80% of the power in Germany according to Renewable Energy law. Due to that reason the conventional power plants are not used for base load, but rather for the supply of average and peak load. The change of the operating mode leads to shorter times at stationary temperatures and the number of faster start-ups/shut-downs of the power plants will increase. As a result of this the components are exposed to an interacting load of creep and fatigue which reduces the lifetimes. The aim of this thesis is the development and verification of a lifetime assessment procedure for components made of the nickel-base alloys Alloy 617 mod. and Alloy 263 under creep fatigue loading conditions based on numerical phenomenological models and on the approaches of different standards/recommendations. The focus lies on two components of the high temperature material test rig II (HWT II), a header made of Alloy 617 mod. and Alloy 263 as well as a formed part made of Alloy 617 mod. For the basis characterization of the HWT II melts, specimens of the Alloy 617 mod. and Alloy 263 are tested in uniaxial tensile tests, (creep-)fatigue tests, creep tests and charpy tests in a temperature range between 20 C and 725 C. From the comparisons of the test results and the material specifications respectively the results of the projects COORETEC DE4, MARCKO DE2 and MARCKO700 no deviations were obvious for both materials with the exception of the creep test results with Alloy 617 mod. material. The creep tests with Alloy 617 mod. material of the HWT II melt show differences regarding the deformation and damage behavior. In addition to the basis characterization tests some complex lab tests for the characterization of the material behavior under creep-fatigue and multiaxial loading conditions were conducted. The developments of the microstructure, the precipitations as well as the structure of dislocations are investigated in the light optical microscope

  16. Lifetime assessment of thick-walled components made of nickel-base alloys under near-service loading conditions; Lebensdauerbewertung dickwandiger Bauteile aus Nickelbasislegierungen unter betriebsnahen Beanspruchungen

    Energy Technology Data Exchange (ETDEWEB)

    Hueggenberg, Daniel

    2015-11-06

    Until 2050 the renewable energies should provide 80% of the power in Germany according to Renewable Energy law. Due to that reason the conventional power plants are not used for base load, but rather for the supply of average and peak load. The change of the operating mode leads to shorter times at stationary temperatures and the number of faster start-ups/shut-downs of the power plants will increase. As a result of this the components are exposed to an interacting load of creep and fatigue which reduces the lifetimes. The aim of this thesis is the development and verification of a lifetime assessment procedure for components made of the nickel-base alloys Alloy 617 mod. and Alloy 263 under creep fatigue loading conditions based on numerical phenomenological models and on the approaches of different standards/recommendations. The focus lies on two components of the high temperature material test rig II (HWT II), a header made of Alloy 617 mod. and Alloy 263 as well as a formed part made of Alloy 617 mod. For the basis characterization of the HWT II melts, specimens of the Alloy 617 mod. and Alloy 263 are tested in uniaxial tensile tests, (creep-)fatigue tests, creep tests and charpy tests in a temperature range between 20 C and 725 C. From the comparisons of the test results and the material specifications respectively the results of the projects COORETEC DE4, MARCKO DE2 and MARCKO700 no deviations were obvious for both materials with the exception of the creep test results with Alloy 617 mod. material. The creep tests with Alloy 617 mod. material of the HWT II melt show differences regarding the deformation and damage behavior. In addition to the basis characterization tests some complex lab tests for the characterization of the material behavior under creep-fatigue and multiaxial loading conditions were conducted. The developments of the microstructure, the precipitations as well as the structure of dislocations are investigated in the light optical microscope

  17. Fatigue and creep at variable temperature. Time dependence forecasting

    International Nuclear Information System (INIS)

    Felsen, M.F.; Mottot, M.; Petrequin, P.

    1984-03-01

    Structure materials for nuclear reactors undergo different types of mechanical and thermal stresses for period reaching 300 000 hours. Rapid change of temperature, stress, frequency can occurs in case of accident. Determination of mechanical properties (elongation, creep, fatigue...) of materials for structure dimensioning requires extrapolation of fatigue and creep tests. The comparison of results obtained on steel 316 shows that for creep forecastings agreement is good between the different methods but it is not the case for creep fatigue. For creep in variable conditions, agreement between experiments and calculus is good only in some cases. For fatigue test with samples previously tested for creep, or vice versa, results depend upon the damage evaluation [fr

  18. When does poor subjective financial position hurt the elderly? Testing the interaction with educational attainment using a national representative longitudinal survey.

    Science.gov (United States)

    Pu, Christy; Huang, Nicole; Tang, Gao-Jun; Chou, Yiing-Jenq

    2011-03-17

    Several studies have demonstrated that perceived financial status has a significant impact on health status among the elderly. However, little is known about whether such a subjective perception interacts with objective socioeconomic status (SES) measures such as education that affect the individual's health. This research used data from the Survey of Health and Living Status of the Middle Age and Elderly in Taiwan (SHLS) conducted by the Bureau of Health Promotion, Department of Health in Taiwan. Waves 1996, 1999 and 2003 were used. The sample consisted of 2,387 elderly persons. The interactive effects of self-rated satisfaction with financial position and educational attainment were estimated. Self-rated health (SRH), depressive symptom (measured by CES-D) and mortality were used to measure health outcomes. Significant interaction effect was found for depressive symptoms. Among those who were dissatisfied with their financial position, those who were illiterate had an odds ratio (OR) of 8.3 (95% CI 4.9 to 14.0) for having depressive symptoms compared with those who were very satisfied with their financial position. The corresponding OR for those with college or above was only 2.7 (95% CI 1.0 to 7.3). No significant interaction effect was found for SRH and mortality. Although poor financial satisfaction was found to be related to poorer health, the strongest association for this effect was observed among those with low educational attainment, and this is especially true for depressive symptoms. Subjective financial status among the elderly should be explored in conjunction with traditional measures of SES.

  19. Mechanical and physical properties of 2 1/4 Cr--1 Mo steel in support of CRBRP steam generator design

    International Nuclear Information System (INIS)

    Brinkman, C.R.; Williams, R.K.; Klueh, R.L.; Hebble, T.L.

    1975-01-01

    Mechanical and physical property tests on annealed 2 1 / 4 Cr-1 Mo steel were conducted in an effort to define behavior in support of the design of the Clinch River Breeder Reactor Plant (CRBRP) steam generator design. Interim empirical expressions and/or data are reported from the results of tensile, creep, fatigue, creep-fatigue, subcritical crack growth, thermal conductivity, thermal diffusivity, and thermal expansion tests and analysis. These expressions cover behavior, where appropriate, over a range of temperatures from 25 to as high as 700 0 C. Comparisons between thermal conductivity and diffusivity values and those found in the American Society of Mechanical Engineers (ASME) Code indicated that the new values were significantly higher than those found presently in the Code. The importance and complexity of obtaining valid mechanical and physical properties for the Clinch River Breeder Reactor Plant (CRBRP) steam generator are discussed. (U.S.)

  20. Understanding Fundamental Material Degradation Processes in High Temperature Aggressive Chemomechanical Environments

    International Nuclear Information System (INIS)

    2014-01-01

    The objective of this project is to develop a fundamental understanding of the mechanisms that limit materials durability for very high-temperature applications. Current design limitations are based on material strength and corrosion resistance. This project will characterize the interactions of high-temperature creep, fatigue, and environmental attack in structural metallic alloys of interest for the very high-temperature gas-cooled reactor (VHTR) or Next Generation Nuclear Plant (NGNP) and for the associated thermo-chemical processing systems for hydrogen generation. Each of these degradation processes presents a major materials design challenge on its own, but in combination, they can act synergistically to rapidly degrade materials and limit component lives. This research and development effort will provide experimental results to characterize creep-fatigue-environment interactions and develop predictive models to define operation limits for high-temperature structural material applications. Researchers will study individually and in combination creep-fatigue-environmental attack processes in Alloys 617, 230, and 800H, as well as in an advanced Ni-Cr oxide dispersion strengthened steel (ODS) system. For comparison, the study will also examine basic degradation processes in nichrome (Ni-20Cr), which is a basis for most high-temperature structural materials, as well as many of the superalloys. These materials are selected to represent primary candidate alloys, one advanced developmental alloy that may have superior high-temperature durability, and one model system on which basic performance and modeling efforts can be based. The research program is presented in four parts, which all complement each other. The first three are primarily experimental in nature, and the last will tie the work together in a coordinated modeling effort. The sections are (1) dynamic creep-fatigue-environment process, (2) subcritical crack processes, (3) dynamic corrosion crack

  1. Understanding Fundamental Material Degradation Processes in High Temperature Aggressive Chemomechanical Environments

    Energy Technology Data Exchange (ETDEWEB)

    Stubbins, James; Gewirth, Andrew; Sehitoglu, Huseyin; Sofronis, Petros; Robertson, Ian

    2014-01-16

    The objective of this project is to develop a fundamental understanding of the mechanisms that limit materials durability for very high-temperature applications. Current design limitations are based on material strength and corrosion resistance. This project will characterize the interactions of high-temperature creep, fatigue, and environmental attack in structural metallic alloys of interest for the very high-temperature gas-cooled reactor (VHTR) or Next–Generation Nuclear Plant (NGNP) and for the associated thermo-chemical processing systems for hydrogen generation. Each of these degradation processes presents a major materials design challenge on its own, but in combination, they can act synergistically to rapidly degrade materials and limit component lives. This research and development effort will provide experimental results to characterize creep-fatigue-environment interactions and develop predictive models to define operation limits for high-temperature structural material applications. Researchers will study individually and in combination creep-fatigue-environmental attack processes in Alloys 617, 230, and 800H, as well as in an advanced Ni-Cr oxide dispersion strengthened steel (ODS) system. For comparison, the study will also examine basic degradation processes in nichrome (Ni-20Cr), which is a basis for most high-temperature structural materials, as well as many of the superalloys. These materials are selected to represent primary candidate alloys, one advanced developmental alloy that may have superior high-temperature durability, and one model system on which basic performance and modeling efforts can be based. The research program is presented in four parts, which all complement each other. The first three are primarily experimental in nature, and the last will tie the work together in a coordinated modeling effort. The sections are (1) dynamic creep-fatigue-environment process, (2) subcritical crack processes, (3) dynamic corrosion – crack

  2. Macromolecular interactions of the bacterial division FtsZ protein: from quantitative biochemistry and crowding to reconstructing minimal divisomes in the test tube.

    Science.gov (United States)

    Rivas, Germán; Alfonso, Carlos; Jiménez, Mercedes; Monterroso, Begoña; Zorrilla, Silvia

    2013-06-01

    The division of Escherichia coli is an essential process strictly regulated in time and space. It requires the association of FtsZ with other proteins to assemble a dynamic ring during septation, forming part of the functionally active division machinery, the divisome. FtsZ reversibly interacts with FtsA and ZipA at the cytoplasmic membrane to form a proto-ring, the first molecular assembly of the divisome, which is ultimately joined by the rest of the division-specific proteins. In this review we summarize the quantitative approaches used to study the activity, interactions, and assembly properties of FtsZ under well-defined solution conditions, with the aim of furthering our understanding of how the behavior of FtsZ is controlled by nucleotides and physiological ligands. The modulation of the association and assembly properties of FtsZ by excluded-volume effects, reproducing in part the natural crowded environment in which this protein has evolved to function, will be described. The subsequent studies on the reactivity of FtsZ in membrane-like systems using biochemical, biophysical, and imaging technologies are reported. Finally, we discuss the experimental challenges to be met to achieve construction of the minimum protein set needed to initiate bacterial division, without cells, in a cell-like compartment. This integrated approach, combining quantitative and synthetic strategies, will help to support (or dismiss) conclusions already derived from cellular and molecular analysis and to complete our understanding on how bacterial division works.

  3. Interaction intimacy organizes networks of antagonistic interactions in different ways.

    Science.gov (United States)

    Pires, Mathias M; Guimarães, Paulo R

    2013-01-06

    Interaction intimacy, the degree of biological integration between interacting individuals, shapes the ecology and evolution of species interactions. A major question in ecology is whether interaction intimacy also shapes the way interactions are organized within communities. We combined analyses of network structure and food web models to test the role of interaction intimacy in determining patterns of antagonistic interactions, such as host-parasite, predator-prey and plant-herbivore interactions. Networks describing interactions with low intimacy were more connected, more nested and less modular than high-intimacy networks. Moreover, the performance of the models differed across networks with different levels of intimacy. All models reproduced well low-intimacy networks, whereas the more elaborate models were also capable of reproducing networks depicting interactions with higher levels of intimacy. Our results indicate the key role of interaction intimacy in organizing antagonisms, suggesting that greater interaction intimacy might be associated with greater complexity in the assembly rules shaping ecological networks.

  4. The Interactive Media Package for Assessment of Communication and Critical Thinking (IMPACCT[c]): Testing a Programmatic Online Communication Competence Assessment System

    Science.gov (United States)

    Spitzberg, Brian H.

    2011-01-01

    IMPACCT is an online survey covering over 40 self-report types of student communication competency, as well as a test of critical thinking based on cognitive problem-solving. The student nominates two peers who rate the student's interpersonal, computer-mediated, group and leadership, and public speaking communication competence. The student takes…

  5. Properties of Alloy 617 for Heat Exchanger Design

    International Nuclear Information System (INIS)

    Wright, R.N.; Carroll, L.J.; Benz, J.K.; Wright, J.K.; Lillo, T.M.; Lybeck, N.J.

    2014-01-01

    Alloy 617 is among the primary candidates for very high temperature reactor heat exchangers anticipated for use up to 950ºC. Elevated temperature properties of this alloy and the mechanisms responsible for the observed tensile, creep and creep-fatigue behavior have been characterized over a wide range of test temperatures up to 1000ºC. Properties from the current experimental program have been combined with archival information from previous VHTR research to provide large data sets for many heats of material, product forms, and weldments. The combined data have been analyzed to determine conservative values of yield and tensile strength, strain rate sensitivity, creep-rupture behavior, fatigue and creep- fatigue properties that can be used for engineering design of reactor components. Phenomenological models have been developed to bound the regions over which the engineering properties are well known or can be confidently extrapolated for use in design. (author)

  6. Properties of Alloy 617 for Heat Exchanger Design

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Richard Neil [Idaho National Laboratory; Carroll, Laura Jill [Idaho National Laboratory; Benz, Julian Karl [Idaho National Laboratory; Wright, Julie Knibloe [Idaho National Laboratory; Lillo, Thomas Martin [Idaho National Laboratory; Lybeck, Nancy Jean [Idaho National Laboratory

    2014-10-01

    Abstract – Alloy 617 is among the primary candidates for very high temperature reactor heat exchangers anticipated for use up to 950ºC. Elevated temperature properties of this alloy and the mechanisms responsible for the observed tensile, creep and creep-fatigue behavior have been characterized over a wide range of test temperatures up to 1000ºC. Properties from the current experimental program have been combined with archival information from previous VHTR research to provide large data sets for many heats of material, product forms, and weldments. The combined data have been analyzed to determine conservative values of yield and tensile strength, strain rate sensitivity, creep-rupture behavior, fatigue and creep- fatigue properties that can be used for engineering design of reactor components. Phenomenological models have been developed to bound the regions over which the engineering properties are well known or can be confidently extrapolated for use in design.

  7. Probing DNA interactions with proteins using a single-molecule toolbox: inside the cell, in a test tube and in a computer.

    Science.gov (United States)

    Wollman, Adam J M; Miller, Helen; Zhou, Zhaokun; Leake, Mark C

    2015-04-01

    DNA-interacting proteins have roles in multiple processes, many operating as molecular machines which undergo dynamic meta-stable transitions to bring about their biological function. To fully understand this molecular heterogeneity, DNA and the proteins that bind to it must ideally be interrogated at a single molecule level in their native in vivo environments, in a time-resolved manner, fast enough to sample the molecular transitions across the free-energy landscape. Progress has been made over the past decade in utilizing cutting-edge tools of the physical sciences to address challenging biological questions concerning the function and modes of action of several different proteins which bind to DNA. These physiologically relevant assays are technically challenging but can be complemented by powerful and often more tractable in vitro experiments which confer advantages of the chemical environment with enhanced detection signal-to-noise of molecular signatures and transition events. In the present paper, we discuss a range of techniques we have developed to monitor DNA-protein interactions in vivo, in vitro and in silico. These include bespoke single-molecule fluorescence microscopy techniques to elucidate the architecture and dynamics of the bacterial replisome and the structural maintenance of bacterial chromosomes, as well as new computational tools to extract single-molecule molecular signatures from live cells to monitor stoichiometry, spatial localization and mobility in living cells. We also discuss recent developments from our laboratory made in vitro, complementing these in vivo studies, which combine optical and magnetic tweezers to manipulate and image single molecules of DNA, with and without bound protein, in a new super-resolution fluorescence microscope.

  8. Testing a model of science process skills acquisition: An interaction with parents' education, preferred language, gender, science attitude, cognitive development, academic ability, and biology knowledge

    Science.gov (United States)

    Germann, Paul J.

    Path analysis techniques were used to test a hypothesized structural model of direct and indirect causal effects of student variables on science process skills. The model was tested twice using data collected at the beginning and end of the school year from 67 9th- and 10th-grade biology students who lived in a rural Franco-American community in New England. Each student variable was found to have significant effects, accounting for approximately 80% of the variance in science process skills achievement. Academic ability, biology knowledge, and language preference had significant direct effects. There were significant mediated effects by cognitive development, parents' education, and attitude toward science in school. The variables of cognitive development and academic ability had the greatest total effects on science process skills. Implications for practitioners and researchers are discussed.

  9. Aerodynamic interactions from reaction controls for lateral control of the M2-F2 lifting-body entry configuration at transonic and supersonic and supersonic Mach numbers. [wind tunnel tests

    Science.gov (United States)

    Bailey, R. O.; Brownson, J. J.

    1979-01-01

    Tests were conducted in the Ames 6 by 6 foot wind tunnel to determine the interaction of reaction jets for roll control on the M2-F2 lifting-body entry vehicle. Moment interactions are presented for a Mach number range of 0.6 to 1.7, a Reynolds number range of 1.2 x 10 to the 6th power to 1.6 x 10 to the 6th power (based on model reference length), an angle-of-attack range of -9 deg to 20 deg, and an angle-of-sideslip range of -6 deg to 6 deg at an angle of attack of 6 deg. The reaction jets produce roll control with small adverse yawing moment, which can be offset by horizontal thrust component of canted jets.

  10. Kinesthetic Interaction

    DEFF Research Database (Denmark)

    Fogtmann, Maiken Hillerup; Fritsch, Jonas; Kortbek, Karen Johanne

    2008-01-01

    Within the Human-Computer Interaction community there is a growing interest in designing for the whole body in interaction design. The attempts aimed at addressing the body have very different outcomes spanning from theoretical arguments for understanding the body in the design process, to more...... practical examples of designing for bodily potential. This paper presents Kinesthetic Interaction as a unifying concept for describing the body in motion as a foundation for designing interactive systems. Based on the theoretical foundation for Kinesthetic Interaction, a conceptual framework is introduced...... to be utilized when analyzing existing designs, as well as developing designs exploring new ways of designing kinesthetic interactions....

  11. Effect of phosphorus element on the comprehensive properties of Sn-Cu lead-free solder

    International Nuclear Information System (INIS)

    Li Guangdong; Shi Yaowu; Hao Hu; Xia Zhidong; Lei Yongping; Guo Fu

    2010-01-01

    In the present work, the effect of phosphorus on the creep fatigue properties of Sn-Cu eutectic lead-free solder was carried out. The experimental results show that the melting temperature was almost not changed with adding small amount of P element. However, the addition of trace P element led to the decrease in the property of creep fatigue. The fractography analysis by a scanning electron microscopy (SEM) shows that ductile fracture was the dominant failure behavior in the process of creep fatigue test of Sn0.7Cu and Sn0.7Cu0.005P specimens. It should be pointed out that there is significant difference in the fractographs between the joints of Sn0.7Cu solder and Sn0.7Cu0.005P solder. In the fractograph of Sn0.7Cu solder joint, the microstructure is prolonged along testing direction, and the dimples were more than the fractograph of Sn0.7Cu0.005P solder joint. In addition, the voids could be found on the Sn0.7Cu0.005P solder joint, and trace P addition may increase the rate of forming void of Sn0.7Cu solder joint. The voids can potentially lead to crack initiation or propagation sites in the solder joint. As a result, the creep fatigue of solder joint containing P such as Sn0.7Cu0.005P offers worse property compared to Sn0.7Cu solder joint.

  12. Personal travel blogs as texts for studying intercultural interactions: a pilot test case study of an American sojourner's blogs from Zimbabwe.

    Science.gov (United States)

    Malleus, Rick; Slattery, Elizabeth

    2014-01-01

    This paper makes the argument that personal travel blogs are an important site for studying self-reports of face-to-face intercultural interaction. The guiding research question is "Are personal travel blogs good sources of intercultural communication data?" A content analysis of an American woman's travel blog, written on a sojourn to Zimbabwe, was performed using four intercultural communication constructs that served as frameworks for developing a rubric and for analysis. Those constructs are: culture shock, intercultural communication challenges, cross-cultural comparison and intercultural adaptation. Results provide evidence of written reflections by the blogger in all four coding categories. The evidence of culture shock provided in the blog was multifold, multifaceted, and congruent with many of the well-established elements of culture shock reported in the field. The evidence of cross-cultural comparison in the personal travel blog was, overwhelmingly, comprised of reflections comparing host and home cultures, both in environment and cultural practices. There was limited evidence of reflections about communication challenges or adaptation by the blogger on her sojourn. The article concludes with a discussion of the implications these findings have for the potential travel blogs might provide for analysis of intercultural communication as well as addressing the limitations of the study's findings.

  13. US Department of Energy Secretary Bill Richardson (centre) at an LHC interaction region quadrupole test cryostat. part of the US contribution to LHC construction and built by the US-LHC collaboration (hence the Fermilab logo)

    CERN Multimedia

    Barbara Warmbein

    2000-01-01

    Photo 01 : September 2000 - Mr Bill Richardson, Secretary of Energy, United States of America (centre) at an LHC interaction region quadrupole test cryostat, part of the US contribution to LHC construction and built by the US-LHC collaboration (hence the Fermilab logo); with l. to r. Dr Mildred Dresselhaus, Dr Carlo Wyss, CERN Director General, Profesor Luciano Maiani, Professor Roger Cashmore, Ambassador George Moose, Dr Peter Rosen, Dr John Ellis. Photo 02 : Mr. Bill Richardson (right), Secretary of Energy United States of America with Prof. Luciano Maiani leaning over one of the LHC magnets produced at Fermilab during his visit to CERN on 16th September 2000.

  14. Inferences on mass composition and tests of hadronic interactions from 0.3 to 100 EeV using the water-Cherenkov detectors of the Pierre Auger Observatory

    Czech Academy of Sciences Publication Activity Database

    Aab, A.; Abreu, P.; Aglietta, M.; Blažek, Jiří; Boháčová, Martina; Chudoba, Jiří; Ebr, Jan; Juryšek, Jakub; Mandát, Dušan; Palatka, Miroslav; Pech, Miroslav; Prouza, Michael; Řídký, Jan; Schovánek, Petr; Trávníček, Petr; Vícha, Jakub

    2017-01-01

    Roč. 96, č. 12 (2017), s. 1-22, č. článku 122003. ISSN 2470-0010 R&D Projects: GA MŠk LM2015038; GA MŠk LG15014; GA MŠk EF16_013/0001402 Grant - others:OP VVV - AUGER-CZ(XE) CZ.02.1.01/0.0/0.0/16_013/0001402 Institutional support: RVO:68378271 Keywords : Cherenkov detectors * Pierre Auger Observatory * tests of hadronic interactions Subject RIV: BF - Elementary Particles and High Energy Physics OBOR OECD: Particles and field physics Impact factor: 4.568, year: 2016

  15. Interactive benchmarking

    DEFF Research Database (Denmark)

    Lawson, Lartey; Nielsen, Kurt

    2005-01-01

    We discuss individual learning by interactive benchmarking using stochastic frontier models. The interactions allow the user to tailor the performance evaluation to preferences and explore alternative improvement strategies by selecting and searching the different frontiers using directional...

  16. Weak interactions

    International Nuclear Information System (INIS)

    Chanda, R.

    1981-01-01

    The theoretical and experimental evidences to form a basis for Lagrangian Quantum field theory for Weak Interactions are discussed. In this context, gauge invariance aspects of such interactions are showed. (L.C.) [pt

  17. Studies of infiltration and lead-soil interactions at the Radioactive Waste Management Site in Area 5 of the Nevada Test Site

    International Nuclear Information System (INIS)

    Case, C.M.; Davis, J.O.; Heidker, J.C.; Whitbeck, M.R.

    1992-07-01

    Several studies were conducted to investigate the possibility of buried lead being transported by water in the unsaturated zone at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada Test Site. All involved soil from a 37-m soil core collected at the RWMS. The core consisted primarily of sand and small pebbles, with occasional layers of loose rocks. Few buried soil horizons were observed, and the core showed no evidence of a carbonate layer that would act as a barrier to infiltration. Samples chosen from various depths in the soil core were analyzed chemically. Calcium and sulfate occurred in a prominent layer about 5 m below the surface. The concentration of soluble carbonate increased gradually with depth, while chloride concentrations decreased. Lead concentrations ranged from 1 to 2 mg/kg. Additional data from the soil core were combined with results of earlier field infiltration studies at two sites near the RWMS to estimate flow velocities for water in the unsaturated zone. Under normal (dry) conditions, the degree of saturation is so small that gravity drainage does not occur; water moves by vapor transport and capillary action. Significant water movement occurs only if the soil is at or near saturation. The results suggest that even continuously ponded water at the RWMS would take several months to infiltrate to the water table. Seven samples from the soil core were tested for their ability to adsorb lead. All took up lead with about the same intensity and capacity. Adsorption of lead by insoluble carbonate minerals and precipitation of lead by soluble carbonate in the soil at the RWMS should provide a barrier to lead migration. Finally, measurements were made of the corrosion rates of lead and steel in contact with soil samples from the core. Corrosion rates generally increased with increasing soil saturation at all depths. Under ambient soil conditions at the RWMS, corrosion rates would be low

  18. Using the FLUKA Monte Carlo Code to Simulate the Interactions of Ionizing Radiation with Matter to Assist and Aid Our Understanding of Ground Based Accelerator Testing, Space Hardware Design, and Secondary Space Radiation Environments

    Science.gov (United States)

    Reddell, Brandon

    2015-01-01

    Designing hardware to operate in the space radiation environment is a very difficult and costly activity. Ground based particle accelerators can be used to test for exposure to the radiation environment, one species at a time, however, the actual space environment cannot be duplicated because of the range of energies and isotropic nature of space radiation. The FLUKA Monte Carlo code is an integrated physics package based at CERN that has been under development for the last 40+ years and includes the most up-to-date fundamental physics theory and particle physics data. This work presents an overview of FLUKA and how it has been used in conjunction with ground based radiation testing for NASA and improve our understanding of secondary particle environments resulting from the interaction of space radiation with matter.

  19. Using genetics to test the causal relationship of total adiposity and periodontitis: Mendelian randomization analyses in the Gene-Lifestyle Interactions and Dental Endpoints (GLIDE) Consortium

    Science.gov (United States)

    Shungin, Dmitry; Cornelis, Marilyn C; Divaris, Kimon; Holtfreter, Birte; Shaffer, John R; Yu, Yau-Hua; Barros, Silvana P; Beck, James D; Biffar, Reiner; Boerwinkle, Eric A; Crout, Richard J.; Ganna, Andrea; Hallmans, Goran; Hindy, George; Hu, Frank B; Kraft, Peter; McNeil, Daniel W; Melander, Olle; Moss, Kevin L; North, Kari E; Orho-Melander, Marju; Pedersen, Nancy L; Ridker, Paul M; Rimm, Eric B; Rose, Lynda M; Rukh, Gull; Teumer, Alexander; Weyant, Robert J; Chasman, Daniel I; Joshipura, Kaumudi; Kocher, Thomas; Magnusson, Patrik KE; Marazita, Mary L; Nilsson, Peter; Offenbacher, Steve; Davey Smith, George; Lundberg, Pernilla; Palmer, Tom M; Timpson, Nicholas J; Johansson, Ingegerd; Franks, Paul W

    2015-01-01

    Background: The observational relationship between obesity and periodontitis is widely known, yet causal evidence is lacking. Our objective was to investigate causal associations between periodontitis and body mass index (BMI). Methods: We performed Mendelian randomization analyses with BMI-associated loci combined in a genetic risk score (GRS) as the instrument for BMI. All analyses were conducted within the Gene-Lifestyle Interactions and Dental Endpoints (GLIDE) Consortium in 13 studies from Europe and the USA, including 49 066 participants with clinically assessed (seven studies, 42.1% of participants) and self-reported (six studies, 57.9% of participants) periodontitis and genotype data (17 672/31 394 with/without periodontitis); 68 761 participants with BMI and genotype data; and 57 871 participants (18 881/38 990 with/without periodontitis) with data on BMI and periodontitis. Results: In the observational meta-analysis of all participants, the pooled crude observational odds ratio (OR) for periodontitis was 1.13 [95% confidence interval (CI): 1.03, 1.24] per standard deviation increase of BMI. Controlling for potential confounders attenuated this estimate (OR = 1.08; 95% CI:1.03, 1.12). For clinically assessed periodontitis, corresponding ORs were 1.25 (95% CI: 1.10, 1.42) and 1.13 (95% CI: 1.10, 1.17), respectively. In the genetic association meta-analysis, the OR for periodontitis was 1.01 (95% CI: 0.99, 1.03) per GRS unit (per one effect allele) in all participants and 1.00 (95% CI: 0.97, 1.03) in participants with clinically assessed periodontitis. The instrumental variable meta-analysis of all participants yielded an OR of 1.05 (95% CI: 0.80, 1.38) per BMI standard deviation, and 0.90 (95% CI: 0.56, 1.46) in participants with clinical data. Conclusions: Our study does not support total adiposity as a causal risk factor for periodontitis, as the point estimate is very close to the null in the causal inference analysis, with wide

  20. In vivo imaging of trypanosome-brain interactions and development of a rapid screening test for drugs against CNS stage trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Elmarie Myburgh

    Full Text Available HUMAN AFRICAN TRYPANOSOMIASIS (HAT MANIFESTS IN TWO STAGES OF DISEASE: firstly, haemolymphatic, and secondly, an encephalitic phase involving the central nervous system (CNS. New drugs to treat the second-stage disease are urgently needed, yet testing of novel drug candidates is a slow process because the established animal model relies on detecting parasitemia in the blood as late as 180 days after treatment. To expedite compound screening, we have modified the GVR35 strain of Trypanosoma brucei brucei to express luciferase, and have monitored parasite distribution in infected mice following treatment with trypanocidal compounds using serial, non-invasive, bioluminescence imaging. Parasites were detected in the brains of infected mice following treatment with diminazene, a drug which cures stage 1 but not stage 2 disease. Intravital multi-photon microscopy revealed that trypanosomes enter the brain meninges as early as day 5 post-infection but can be killed by diminazene, whereas those that cross the blood-brain barrier and enter the parenchyma by day 21 survived treatment and later caused bloodstream recrudescence. In contrast, all bioluminescent parasites were permanently eliminated by treatment with melarsoprol and DB829, compounds known to cure stage 2 disease. We show that this use of imaging reduces by two thirds the time taken to assess drug efficacy and provides a dual-modal imaging platform for monitoring trypanosome infection in different areas of the brain.

  1. Testing the SI × SC rule: Pollen-pistil interactions in interspecific crosses between members of the tomato clade (Solanum section Lycopersicon, Solanaceae).

    Science.gov (United States)

    Baek, You Soon; Covey, Paul A; Petersen, Jennifer J; Chetelat, Roger T; McClure, Bruce; Bedinger, Patricia A

    2015-02-01

    Interspecific reproductive barriers (IRBs) act to ensure species integrity by preventing hybridization. Previous studies on interspecific crosses in the tomato clade have focused on the success of fruit and seed set. The SI × SC rule (SI species × SC species crosses are incompatible, but the reciprocal crosses are compatible) often applies to interspecific crosses. Because SI systems in the Solanaceae affect pollen tube growth, we focused on this process in a comprehensive study of interspecific crosses in the tomato clade to test whether the SI × SC rule was always followed. Pollen tube growth was assessed in reciprocal crosses between all 13 species of the tomato clade using fluorescence microscopy. In crosses between SC and SI species, pollen tube growth follows the SI × SC rule: interspecific pollen tube rejection occurs when SI species are pollinated by SC species, but in the reciprocal crosses (SC × SI), pollen tubes reach ovaries. However, pollen tube rejection occurred in some crosses between pairs of SC species, demonstrating that a fully functional SI system is not necessary for pollen tube rejection in interspecific crosses. Further, gradations in the strength of both pistil and pollen IRBs were revealed in interspecific crosses using SC populations of generally SI species. The SI × SC rule explains many of the compatibility relations in the tomato clade, but exceptions occur with more recently evolved SC species and accessions, revealing differences in strength of both pistil and pollen IRBs. © 2015 Botanical Society of America, Inc.

  2. Effect modification of air pollution on Urinary 8-Hydroxy-2'-Deoxyguanosine by genotypes: an application of the multiple testing procedure to identify significant SNP interactions

    Directory of Open Access Journals (Sweden)

    Christiani David C

    2010-12-01

    Full Text Available Abstract Background Air pollution is associated with adverse human health, but mechanisms through which pollution exerts effects remain to be clarified. One suggested pathway is that pollution causes oxidative stress. If so, oxidative stress-related genotypes may modify the oxidative response defenses to pollution exposure. Methods We explored the potential pathway by examining whether an array of oxidative stress-related genes (twenty single nucleotide polymorphisms, SNPs in nine genes modified associations of pollutants (organic carbon (OC, ozone and sulfate with urinary 8-hydroxy-2-deoxygunosine (8-OHdG, a biomarker of oxidative stress among the 320 aging men. We used a Multiple Testing Procedure in R modified by our team to identify the significance of the candidate genes adjusting for a priori covariates. Results We found that glutathione S-tranferase P1 (GSTP1, rs1799811, M1 and catalase (rs2284367 and group-specific component (GC, rs2282679, rs1155563 significantly or marginally significantly modified effects of OC and/or sulfate with larger effects among those carrying the wild type of GSTP1, catalase, non-wild type of GC and the non-null of GSTM1. Conclusions Polymorphisms of oxidative stress-related genes modified effects of OC and/or sulfate on 8-OHdG, suggesting that effects of OC or sulfate on 8-OHdG and other endpoints may be through the oxidative stress pathway.

  3. Interactive lecturing.

    Science.gov (United States)

    White, Geoff

    2011-12-01

    Lectures can vary from being entirely teacher-centred through to those that value learner-teacher and learner-learner interaction. Advocates of the exclusively didactic (teacher-centred) lecture aim to maximise the amount of lecture time available to their delivery of content, and regard other activities as 'lost' lecture time. Educational research has, however, identified the potential benefit of interactivity that promotes mentally active learning and improved learning outcomes. This article reviews the notion of 'active learning', outlines how active learning is promoted by interactivity and concludes with strategies for including interactivity within lectures. Narrative review and discussion. The article begins with a summary of the purposes of lecturing, and the distinctions between mentally active and passive learning. The associations between interactivity, cognitively active learning and improved learning outcomes are considered, and strategies for promoting interactivity and active learning are explored. Three student-student interaction strategies are discussed, and an exemplar of each of these strategies in action is provided. The exemplar addresses the 'lost time' concern of some advocates of the exclusively didactic lecture. Interactivity can be readily introduced to lectures without a significant reduction in the amount of time available for didactic lecturing. This paper challenges the view that the inclusion of interactivity equates to a loss of learning time, by showing that students' achievement of learning outcomes is enhanced by planned and structured engagement with others. The paper concludes with an example of how interactivity can be incorporated within the traditional lecture format. © Blackwell Publishing Ltd 2011.

  4. Determining the ion temperature and energy distribution in a lithium-plasma interaction test stand with a retarding field energy analyzer

    Science.gov (United States)

    Christenson, M.; Stemmley, S.; Jung, S.; Mettler, J.; Sang, X.; Martin, D.; Kalathiparambil, K.; Ruzic, D. N.

    2017-08-01

    The ThermoElectric-driven Liquid-metal plasma-facing Structures (TELS) experiment at the University of Illinois is a gas-puff driven, theta-pinch plasma source that is used as a test stand for off-normal plasma events incident on materials in the edge and divertor regions of a tokamak. The ion temperatures and resulting energy distributions are crucial for understanding how well a TELS pulse can simulate an extreme event in a larger, magnetic confinement device. A retarding field energy analyzer (RFEA) has been constructed for use with such a transient plasma due to its inexpensive and robust nature. The innovation surrounding the use of a control analyzer in conjunction with an actively sampling analyzer is presented and the conditions of RFEA operation are discussed, with results presented demonstrating successful performance under extreme conditions. Such extreme conditions are defined by heat fluxes on the order of 0.8 GW m-2 and on time scales of nearly 200 μs. Measurements from the RFEA indicate two primary features for a typical TELS discharge, following closely with the pre-ionizing coaxial gun discharge characteristics. For the case using the pre-ionization pulse (PiP) and the theta pinch, the measured ion signal showed an ion temperature of 23.3 ± 6.6 eV for the first peak and 17.6 ± 1.9 eV for the second peak. For the case using only the PiP, the measured signal showed an ion temperature of 7.9 ± 1.1 eV for the first peak and 6.6 ± 0.8 eV for the second peak. These differences illustrate the effectiveness of the theta pinch for imparting energy on the ions. This information also highlights the importance of TELS as being one of the few linear pulsed plasma sources whereby moderately energetic ions will strike targets without the need for sample biasing.

  5. Weak interactions

    International Nuclear Information System (INIS)

    Ogava, S.; Savada, S.; Nakagava, M.

    1983-01-01

    The problem of the use of weak interaction laws to study models of elementary particles is discussed. The most typical examples of weak interaction is beta-decay of nucleons and muons. Beta-interaction is presented by quark currents in the form of universal interaction of the V-A type. Universality of weak interactions is well confirmed using as examples e- and μ-channels of pion decay. Hypothesis on partial preservation of axial current is applicable to the analysis of processes with pion participation. In the framework of the model with four flavours lepton decays of hadrons are considered. Weak interaction without lepton participation are also considered. Properties of neutral currents are described briefly

  6. Explicit Interaction

    DEFF Research Database (Denmark)

    Löwgren, Jonas; Eriksen, Mette Agger; Linde, Per

    2006-01-01

    We report an ongoing study of palpable computing to support surgical rehabilitation, in the general field of interaction design for ubiquitous computing. Through explorative design, fieldwork and participatory design techniques, we explore the design principle of explicit interaction...... as an interpretation of palpability, comprising usability as well as patient empowerment and socially performative issues. We present a prototype environment for video recording during physiotherapeutical consultation which illustrates our current thoughts on explicit interaction and serves as material for further...

  7. Floor interaction

    DEFF Research Database (Denmark)

    Petersen, Marianne Graves; Krogh, Peter; Ludvigsen, Martin

    2005-01-01

    Within architecture, there is a long tradition of careful design of floors. The design has been concerned with both decorating floors and designing floors to carry information. Ubiquitous computing technology offers new opportunities for designing interactive floors. This paper presents three...... different interactive floor concepts. Through an urban perspective it draws upon the experiences of floors in architecture, and provides a set of design issues for designing interactive floors....

  8. Interactive Timetabling

    OpenAIRE

    Muller, Tomas; Bartak, Roman

    2001-01-01

    Timetabling is a typical application of constraint programming whose task is to allocate activities to slots in available resources respecting various constraints like precedence and capacity. In this paper we present a basic concept, a constraint model, and the solving algorithms for interactive timetabling. Interactive timetabling combines automated timetabling (the machine allocates the activities) with user interaction (the user can interfere with the process of timetabling). Because the ...

  9. Playful Interaction

    DEFF Research Database (Denmark)

    2003-01-01

    The video Playful Interaction describes a future architectural office, and envisions ideas and concepts for playful interactions between people, materials and appliances in a pervasive and augmented working environment. The video both describes existing developments, technologies and designs...... as well as ideas not yet implemented such as playful modes of interaction with an augmented ball. Playful Interaction has been used as a hybrid of a vision video and a video prototype (1). Externally the video has been used to visualising our new ideas, and internally the video has also worked to inspire...

  10. Aesthetic Interaction

    DEFF Research Database (Denmark)

    Ludvigsen, Martin; Petersen, M.G.; Iversen, O.

    2004-01-01

    , as it promotes aesthetics of use, rather than aesthetics of appearance. We coin this approach in the perspective of aesthetic interaction. Finally we make the point that aesthetics is not re-defining everything known about interactive systems. We provide a framework placing this perspective among other...

  11. Collocated Interaction

    DEFF Research Database (Denmark)

    E. Fischer, Joel; Porcheron, Martin; Lucero, Andrés

    2016-01-01

    , and wearable technologies, spaces and spatial interaction, and those interested in the social aspects of interaction, such as conversation analysis and ethnomethodology. These communities have matured considerably, and produced significant exemplars of systems, methods, and studies concerned with collocated...... interactions. Yet, new challenges abound as people wear and carry more devices than ever, creating fragmented device ecologies at work, and changing the ways we socialise with each other. In this workshop we seek to start a dialogue to look back as well as forward, review best practices, discuss and design...

  12. Programming Interactivity

    CERN Document Server

    Noble, Joshua

    2012-01-01

    Ready to create rich interactive experiences with your artwork, designs, or prototypes? This is the ideal place to start. With this hands-on guide, you'll explore several themes in interactive art and design-including 3D graphics, sound, physical interaction, computer vision, and geolocation-and learn the basic programming and electronics concepts you need to implement them. No previous experience is necessary. You'll get a complete introduction to three free tools created specifically for artists and designers: the Processing programming language, the Arduino microcontroller, and the openFr

  13. Usability Test of an Interactive Dietary Recording

    Science.gov (United States)

    Chung, Louisa Ming Yan; Chung, Joanne Wai Yee; Wong, Thomas Kwok Shing

    2009-01-01

    Dietary intake methods are used to collect one's diet habit which is essential in nutrition assessment. Food diary, food frequency questionnaire (FFQ) and 24-hour recalls are the most common dietary intake methods. However, they are not welcomed by most clients. Digital handheld devices are now readily available, and the cost of digital…

  14. Interaction graphs

    DEFF Research Database (Denmark)

    Seiller, Thomas

    2016-01-01

    Interaction graphs were introduced as a general, uniform, construction of dynamic models of linear logic, encompassing all Geometry of Interaction (GoI) constructions introduced so far. This series of work was inspired from Girard's hyperfinite GoI, and develops a quantitative approach that should...... be understood as a dynamic version of weighted relational models. Until now, the interaction graphs framework has been shown to deal with exponentials for the constrained system ELL (Elementary Linear Logic) while keeping its quantitative aspect. Adapting older constructions by Girard, one can clearly define...... "full" exponentials, but at the cost of these quantitative features. We show here that allowing interpretations of proofs to use continuous (yet finite in a measure-theoretic sense) sets of states, as opposed to earlier Interaction Graphs constructions were these sets of states were discrete (and finite...

  15. Embarrassing Interactions

    DEFF Research Database (Denmark)

    Deterding, Sebastian; Lucero, Andrés; Holopainen, Jussi

    2015-01-01

    Wherever the rapid evolution of interactive technologies disrupts standing situational norms, creates new, often unclear situational audiences, or crosses cultural boundaries, embarrassment is likely. This makes embarrassment a fundamental adoption and engagement hurdle, but also a creative design...

  16. Interaction Widget

    DEFF Research Database (Denmark)

    Ingstrup, Mads

    2003-01-01

    This pattern describes the idea of making a user interface of discrete, reusable entities---here called interaction widgets. The idea behind widgets is described using two perspectives, that of the user and that of the developer. It is the forces from these two perspectives that are balanced...... in the pattern. The intended audience of the pattern is developers and researchers within the field of human computer interaction....

  17. Hair Interactions

    OpenAIRE

    Cani, Marie-Paule; Bertails, Florence

    2006-01-01

    International audience; Processing interactions is one of the main challenges in hair animation. Indeed, in addition to the collisions with the body, an extremely large number of contacts with high friction rates are permanently taking place between individual hair strands. Simulating the latter is essential: without hair self-interactions, strands would cross each other during motion or come to rest at the same location, yielding unrealistic behavior and a visible lack of hair volume. This c...

  18. Interactive videodisc in maintenance

    International Nuclear Information System (INIS)

    Zwingelstein, G.; Nguyen Van Nghi, B.

    1986-01-01

    After a recall of the videodisc characteristics, this paper presents its utilization by Electricite de France in the framework of training and maintenance. The SICMA (Interactive Communication System in Maintenance) developed and tested by Electricte de France is presented as also its utilization. It has been tested on the sites of Dampierre and Paluel in the cases of training and maintenance (deconnexion of drive rods of control elements); the conclusions of this experimentation are finally given. 4 refs [fr

  19. Interactive Information Retrieval

    DEFF Research Database (Denmark)

    Borlund, Pia

    2013-01-01

    The paper introduces the research area of interactive information retrieval (IIR) from a historical point of view. Further, the focus here is on evaluation, because much research in IR deals with IR evaluation methodology due to the core research interest in IR performance, system interaction...... and satisfaction with retrieved information. In order to position IIR evaluation, the Cranfield model and the series of tests that led to the Cranfield model are outlined. Three iconic user-oriented studies and projects that all have contributed to how IIR is perceived and understood today are presented......: The MEDLARS test, the Book House fiction retrieval system, and the OKAPI project. On this basis the call for alternative IIR evaluation approaches motivated by the three revolutions (the cognitive, the relevance, and the interactive revolutions) put forward by Robertson & Hancock-Beaulieu (1992) is presented...

  20. Space for Interaction

    DEFF Research Database (Denmark)

    Jørgensen, Mariane Ellen; Folmer, Mette Blicher; Mullins, Michael

    SPACE FOR INTERACTION QUALIFYING GROUP TREATMENT FOR PATIENTS WITH CHRONIC PAIN THROUGH OPTIMIZATION(?) OF SPACE. A RANDOMIZED PILOT STUDY. In a Ph-D. Mariane Ellen Jørgensen / Nurse + psykoterapist / maej@rn.dk / Pain Center / Aalborg University Hospital / Denmark / Mette Blicher Folmer...... Building Research Institute / Aalborg University / Denmark AIM Research shows the hospital space has significance for human healing processes and the physical environment can have both positive and negative impact on the interaction between patients and staff. In order to qualify treatment for patients...... with chronic pain, the effect and experience of two different rooms for group therapy were compared. Three hypotheses were tested: 1) Room decor affects the interaction and thus the psychotherapeutic group therapy 2) The meaning of space for the interaction could be measured on the effect of treatment 3...

  1. Interaction region

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The Interaction Region Group addressed the basic questions of how to collide the SLC beams, how to maximize and monitor the luminosity, and how to minimize the detector backgrounds at the interaction region. In practice, five subgroups evolved to study these questions. The final focus group provided three alternative designs to acheive the 1 to 2 micron beam spot size required by the SLC, as well as studying other problems including: eta, eta' matching from the collider arcs, the implementation of soft bends near the interaction region, beam emittance growth, and magnet tolerances in the final focus. The beam position monitor group proposed two devices, a strip line monitor, and a beamstrahlung monitor, to bring the beams into collision. The luminosity monitor group reviewed the possible QED processes that would be insensitive to weak interaction (Z 0 ) effects. The beam dumping group proposed locations for kicker and septum magnets in the final focus that would achieve a high dumping efficiency and would meet the desired beam tolerances at the Moller scattering target in the beam dump line. Working with the Polarization Group, the Moller experiment was designed into the beam dump beam line. A beam dump was proposed that would maintain radiation backgrounds (penetrating muons) at acceptible levels. The detector backgrounds group proposed soft-bend and masking configurations to shield the detector from synchrotron radiation from the hard/soft bends and from the final focus quadrupoles and evaluated the effectiveness of these designs for the three final focus optics designs. Backgrounds were also estimated from: large angle synchrotron radiation, local and distant beam-gas interactions, 2-photon interactions, and from neutrons and backscattered photons from the beamstrahlung dump

  2. Programming Interactivity

    CERN Document Server

    Noble, Joshua

    2009-01-01

    Make cool stuff. If you're a designer or artist without a lot of programming experience, this book will teach you to work with 2D and 3D graphics, sound, physical interaction, and electronic circuitry to create all sorts of interesting and compelling experiences -- online and off. Programming Interactivity explains programming and electrical engineering basics, and introduces three freely available tools created specifically for artists and designers: Processing, a Java-based programming language and environment for building projects on the desktop, Web, or mobile phonesArduino, a system t

  3. Simple Interactions

    DEFF Research Database (Denmark)

    and international public. The exhibition Simple Interactions. Sound Art from Japan presents works by 9 Japanese artists at the Museum of Contemporary Art Roskilde. The exhibition mixes installations, performances and documentations, all of which examine how simple interactions can create complex systems...... and patterns. Works and performances by the following artists are presented: Yuji DOGANE - Yukio FUJIMOTO - Atsuhiro ITO - Soichiro MIHARA - Atsushi NISHIJIMA - Jio SHIMIZU - Toshiya TSUNODA - Tetsuya UMEDA - Miki YUI The book presents texts by Minoru HATANAKa; Takashi KOJIMA, Rune SØCHTING and the editors...

  4. Interactive Information Retrieval:

    DEFF Research Database (Denmark)

    Borlund, Pia

    of the users to ensure a complete and realistic picture to enhance our understanding of IIR. The presentation also reflects on whether a re-thinking of the concept on an information need is necessary. One may ask whether it still makes sense to talk about types of information needs. Or should we rather study......This presentation addresses methodological issues of interactive information retrieval (IIR) evaluation in terms of what it entails to study users' use and interaction with IR systems, as well as their satisfaction with retrieved information. In particular, the presentation focuses on test design......, and it takes a look into the toolbox of IIR test design with reference to data collection methods and test procedure. It calls for careful and well-planned studies to qualify the knowledgebase generated as a result of the conducted IIR studies. The presentation further reflects on the need for an updated...

  5. Joint testing of genotypic and gene-environment interaction identified novel association for BMP4 with non-syndromic CL/P in an Asian population using data from an International Cleft Consortium.

    Science.gov (United States)

    Chen, Qianqian; Wang, Hong; Schwender, Holger; Zhang, Tianxiao; Hetmanski, Jacqueline B; Chou, Yah-Huei Wu; Ye, Xiaoqian; Yeow, Vincent; Chong, Samuel S; Zhang, Bo; Jabs, Ethylin Wang; Parker, Margaret M; Scott, Alan F; Beaty, Terri H

    2014-01-01

    Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common disorder with complex etiology. The Bone Morphogenetic Protein 4 gene (BMP4) has been considered a prime candidate gene with evidence accumulated from animal experimental studies, human linkage studies, as well as candidate gene association studies. The aim of the current study is to test for linkage and association between BMP4 and NSCL/P that could be missed in genome-wide association studies (GWAS) when genotypic (G) main effects alone were considered. We performed the analysis considering G and interactions with multiple maternal environmental exposures using additive conditional logistic regression models in 895 Asian and 681 European complete NSCL/P trios. Single nucleotide polymorphisms (SNPs) that passed the quality control criteria among 122 genotyped and 25 imputed single nucleotide variants in and around the gene were used in analysis. Selected maternal environmental exposures during 3 months prior to and through the first trimester of pregnancy included any personal tobacco smoking, any environmental tobacco smoke in home, work place or any nearby places, any alcohol consumption and any use of multivitamin supplements. A novel significant association held for rs7156227 among Asian NSCL/P and non-syndromic cleft lip and palate (NSCLP) trios after Bonferroni correction which was not seen when G main effects alone were considered in either allelic or genotypic transmission disequilibrium tests. Odds ratios for carrying one copy of the minor allele without maternal exposure to any of the four environmental exposures were 0.58 (95%CI = 0.44, 0.75) and 0.54 (95%CI = 0.40, 0.73) for Asian NSCL/P and NSCLP trios, respectively. The Bonferroni P values corrected for the total number of 117 tested SNPs were 0.0051 (asymptotic P = 4.39*10(-5)) and 0.0065 (asymptotic P = 5.54*10(-5)), accordingly. In European trios, no significant association was seen for any SNPs after Bonferroni

  6. Electromagnetic processes and interactions

    International Nuclear Information System (INIS)

    Scheck, F.

    1983-01-01

    The electron and muon are important tools in testing the structure of the fundamental electromagnetic interactions. On the other hand, if these interactions are known, they serve as ideal probes for the internal structure of complex hadronic targets such as nucleons and nuclei. Purely electromagnetic interactions play a distinctive role, for obvious experimental reasons: At low and intermediate energies the effective electromagnetic coupling is larger by many orders of magnitude than the weak couplings, so that electromagnetic processes are measurable to much higher accuracy than purely weak processes. The present chapter deals primarily with applications of charged leptons to problems of nucleon and nuclear structure, and to selected precision tests of quantum electrodynamics (QED) at low momentum transfers. In most of these applications the electromagnetic interactions effectively appear in the form of external fields in the leptonic particle's Dirac equation. This is the domain where the physics of (electromagnetically) interacting leptons can still be described in the framework of an effective, though relativistic, single particle theory. (orig.)

  7. Interactive Governance

    DEFF Research Database (Denmark)

    Bang, Henrik

    2016-01-01

    and growth. However, interactive governance is not a property or effect of institutions; nor does it apply solely to those individuals who seek success above everything else. It is connective more than individualistic or collectivistic in nature; and it manifests a governability capacity which...

  8. Interactive Storytelling

    DEFF Research Database (Denmark)

    Schoenau-Fog, Henrik; Reng, Lars

    2015-01-01

    This book constitutes the refereed proceedings of the 8th International Conference on Interactive Digital Storytelling, ICIDS 2015, held in Copenhagen, Denmark, in November/December 2015. The 18 revised full papers and 13 short papers presented together with 9 posters, 9 workshop descriptions, an...

  9. Cardiopulmonary interactions

    African Journals Online (AJOL)

    2006-08-28

    Aug 28, 2006 ... Any treatise on cardiopulmonary interactions has at its foundation a thorough understanding of both pulmonary and cardiac physiology. Although recent articles have addressed advances in the field1 or applications to a particular subspecialty,2-5 the reader is advised to have basic physiological articles ...

  10. Hadron interactions

    International Nuclear Information System (INIS)

    Fischer, J.; Kolar, P.; Kundrat, V.

    1988-01-01

    The proceedings contain invited lectures and papers presente at the symposium. Attention was devoted to hadron interactions a high energy in QCD, to the structure and decay of hadrons, the production of hadrons and supersymmetric particles in e + e - and ep collisions, to perturbation theory in quantum field theory, and new supersymmetric extensions of relativistic algebra. (Z.J

  11. Interactive Astronomy.

    Science.gov (United States)

    Martin, Jean K.

    1997-01-01

    Presents guiding principles for developing interactive lessons for the World Wide Web. Describes "Amazing Space: Education Online from the Hubble Space Telescope", a program where students study spectacular Hubble Space Telescope images of stars and star-forming regions to learn about the life cycle of stars and the creation of atoms. (JRH)

  12. Testing for Software Safety

    Science.gov (United States)

    Chen, Ken; Lee, Yann-Hang; Wong, W. Eric; Xu, Dianxiang

    2007-01-01

    This research focuses on testing whether or not the hazardous conditions identified by design-level fault tree analysis will occur in the target implementation. Part 1: Integrate fault tree models into functional specifications so as to identify testable interactions between intended behaviors and hazardous conditions. Part 2: Develop a test generator that produces not only functional tests but also safety tests for a target implementation in a cost-effective way. Part 3: Develop a testing environment for executing generated functional and safety tests and evaluating test results against expected behaviors or hazardous conditions. It includes a test harness as well as an environment simulation of external events and conditions.

  13. Measuring L2 speakers’ interactional ability using interactive speech tasks

    NARCIS (Netherlands)

    van Batenburg, Eline S. L.; Oostdam, Ron J.; van Gelderen, Amos J. S.; de Jong, Nivja H.

    2016-01-01

    This article explores ways to assess interactional performance, and reports on the use of a test format that standardizes the interlocutor?s linguistic and interactional contributions to the exchange. It describes the construction and administration of six scripted speech tasks (instruction, advice,

  14. Toroid magnet test facility

    CERN Multimedia

    2002-01-01

    Because of its exceptional size, it was not feasible to assemble and test the Barrel Toroid - made of eight coils - as an integrated toroid on the surface, prior to its final installation underground in LHC interaction point 1. It was therefore decided to test these eight coils individually in a dedicated test facility.

  15. Usability testing for dummies

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Usability testing seems complicated and time-consuming. Is it though? In fact, it is the best way to understand how real users experience your product. In this interactive session, we will do a live usability test and you will get advice on how to conduct your own usability tests.

  16. Gaze interaction from bed

    DEFF Research Database (Denmark)

    Hansen, John Paulin; San Agustin, Javier; Jensen, Henrik Tomra Skovsgaard Hegner

    2011-01-01

    This paper presents a low-cost gaze tracking solution for bedbound people composed of free-ware tracking software and commodity hardware. Gaze interaction is done on a large wall-projected image, visible to all people present in the room. The hardware equipment leaves physical space free to assist...... the person. Accuracy and precision of the tracking system was tested in an experiment with 12 subjects. We obtained a tracking quality that is sufficiently good to control applications designed for gaze interaction. The best tracking condition were achieved when people were sitting up compared to lying down...

  17. Noise and noise disturbances from wind power plants - Tests with interactive control of sound parameters for more comfortable and less perceptible sounds; Buller och bullerstoerningar fraan vindkraftverk - Foersoek med interaktiv styrning av ljudparametrar foer behagligare och mindre maerkbara ljud

    Energy Technology Data Exchange (ETDEWEB)

    Persson-Waye, K.; Oehrstroem, E.; Bjoerkman, M.; Agge, A. [Goeteborg Univ. (Sweden). Dept. of Environmental Medicine

    2001-12-01

    In experimental pilot studies, a methodology has been worked out for interactively varying sound parameters in wind power plants. In the tests, 24 persons varied the center frequency of different band-widths, the frequency of a sinus-tone and the amplitude-modulation of a sinus-tone in order to create as comfortable a sound as possible. The variations build on the noise from the two wind turbines Bonus and Wind World. The variations were performed with a constant dba level. The results showed that the majority preferred a low-frequency tone (94 Hz and 115 Hz for Wind World and Bonus, respectively). The mean of the most comfortable amplitude-modulation varied between 18 and 22 Hz, depending on the ground frequency. The mean of the center-frequency for the different band-widths varied from 785 to 1104 Hz. In order to study the influence of the wind velocity on the acoustic character of the noise, a long-time measurement program has been performed. A remotely controlled system has been developed, where wind velocity, wind direction, temperature and humidity are registered simultaneously with the noise. Long-time registrations have been performed for four different wing turbines.

  18. Nucleation of cracks from shear-induced cavities in an {alpha}/{beta} titanium alloy in fatigue, room-temperature creep and dwell-fatigue

    Energy Technology Data Exchange (ETDEWEB)

    Lefranc, P. [LMPM, UMR CNRS 6617, ENSMA, 86961 Futuroscope, Chasseneuil Cedex (France); LMS, UMR CNRS 7649, Ecole Polytechnique, 91128 Palaiseau Cedex (France); SNECMA Groupe SAFRAN, 77550 Moissy Cramayel (France); Doquet, V. [LMS, UMR CNRS 7649, Ecole Polytechnique, 91128 Palaiseau Cedex (France)], E-mail: doquet@lms.polytechnique.fr; Gerland, M.; Sarrazin-Baudoux, C. [LMPM, UMR CNRS 6617, ENSMA, 86961 Futuroscope, Chasseneuil Cedex (France)

    2008-10-15

    In titanium alloys, dwell periods during room-temperature stress-controlled fatigue tests are responsible for substantial reductions in lifetime compared to pure fatigue loading. The mechanisms of such a creep-fatigue interaction have been investigated for alloy Ti-6242. Scanning and transmission electron microscopy observations revealed crack initiation by coalescence of shear-induced cavities nucleated at {alpha}/{beta} interfaces in large colonies of {alpha} laths nearly parallel to the loading axis. The density and average size of cavities were larger in dwell-fatigue and creep than in fatigue. A qualitative micromechanical model of cavity nucleation based on discrete dislocation dynamics was developed. The number of cycles for cavity nucleation was computed as a function of the applied stress range. A finite threshold, dependent on the size of {alpha} laths colonies with similar orientation, was found. The simulations predict earlier cavity nucleation in creep or dwell-fatigue than in pure fatigue, which is consistent with the performed experiments.

  19. Interactive cinema : engagement and interaction

    NARCIS (Netherlands)

    Vosmeer, Mirjam; Schouten, Ben; Mitchell, Alex; Fernández-Vara, Clara; Thue, David

    2014-01-01

    Technologies that were initially developed to be applied within the domain of video games are currently being used in experiments to explore their meaning and possibilities for cinema and cinema audiences. In this position paper we examine how narrativity, interactivity and engagement are mutually

  20. Interactive governance

    DEFF Research Database (Denmark)

    Sørensen, Eva; Torfing, Jacob; Peters, B. Guy

    , but all these forms represent means of governing involving mixtures of state action with the actions of other entities.This book explores thoroughly this meaning of governance, and links it to broader questions of governance. In the process of explicating this dimension of governance the authors also...... explore some of the more fundamental questions about governance theory. For example, although governance is talked about a great deal political science has done relatively little about how to measure this concept. Likewise, the term multi-level governance has become widely used but its important...... to understand that idea more fully and see how it functions in the context of interactive forms of governance. The authors also link governance to some very fundamental questions in political science and the social sciences more broadly. How is power exercised in interactive governance? How democratic...