Evaluation of wet tantalum capacitors after exposure to extended periods of ripple current, volume 1

The application of tantalum capacitors in the Viking Lander includes both dc voltage and ripple current electrical stress, high temperature during nonoperating times (sterilization), and high vibration and shock loads. The capacitors must survive these severe environments without any degradation if reliable performance is to be achieved. A test program was established to evaluate both wet-slug tantalum and wet-foil capacitors under conditions accurately duplicating actual Viking applications. Test results of the electrical performance characteristics during extended periods of ripple current, the characteristics of the internal silver migration as a function for extended periods of ripple current, and the existence of any memory characteristics are presented

Random and Correlated Phases of Primordial Gravitaional Waves

The phases of primordial gravity waves is analysed in detail within a quantum mechanical context following the formalism developed by Grishchuk and Sidorov. It is found that for physically relevant wavelengths both the phase of each individual mode and the phase {\it difference} between modes are randomly distributed. The phase {\it sum} between modes with oppositely directed wave-vectors, however, is not random and takes on a definite value with no rms fluctuation. The conventional point of view that primordial gravity waves appear after inflation as a classical, random stochastic background is also addressed.Comment: 14 pages, written in REVTE

Multispecies methods, technologies for play

School of Desig

Gyrokinetic Simulations of ETG and ITG Turbulence

Published gyrokinetic continuum-code simulations indicated levels of the electron thermal conductivity {chi}{sub e} due to electron-temperature-gradient (ETG) turbulence large enough to be significant in some tokamaks, while subsequent global particle-in-cell (PIC) simulations gave significantly lower values. We have carried out an investigation of this discrepancy. We have reproduced the key features of the aforementioned PIC simulations using the flux-tube gyrokinetic PIC code, PG3EQ, thereby eliminating global effects and as the cause of the discrepancy. We show that the late-time low-transport state in both of these sets of PIC simulations is a result of discrete particle noise, which is a numerical artifact. Thus, the low value of {chi}{sub e} along with conclusions about anomalous transport drawn from these particular PIC simulations are unjustified. In our attempts to benchmark PIC and continuum codes for ETG turbulence at the plasma parameters used above, both produce very large intermittent transport. We have therefore undertaken benchmarks at an alternate reference point, magnetic shear s=0.1 instead of s=0.796, and have found that PIC and continuum codes reproduce the same transport levels. Scans in the magnetic shear show an abrupt transition to a high-{chi}{sub e} state as the shear is increased above s=0.4. When nonadiabatic ions are used, this abrupt transition is absent, and {chi}{sub e} increases gradually reaching values consistent with transport analyses of DIII-D, JET, and JT60-U discharges. New results on the balances of zonal-flow driving and damping terms in late-time quasi-steady ITG turbulence and on real-geometry gyrokinetic simulations of shaped DIII-D discharges are also reported

Artifact and Artifact Categorization: Comparing Humans and Capuchin Monkeys

International audienceWe aim to show that far-related primates like humans and the capuchin monkeys show interesting correspondences in terms of artifact characterization and categorization. We investigate this issue by using a philosophically-inspired definition of physical artifact which, developed for human artifacts, turns out to be applicable for cross-species comparison. In this approach an artifact is created when an entity is intentionally selected and some capacities attributed to it (often characterizing a purpose). Behavioral studies suggest that this notion of artifact is not specific to the human kind. On the basis of the results of a series of field observations and experiments on wild capuchin monkeys that routinely use stone hammers and anvils, we show that the notions of intentional selection and attributed capacity appear to be at play in capuchins as well. The study also suggests that functional criteria and contextualization play a fundamental role in terms of artifact recognition and categorization in nonhuman primates

The MiniArc sling for female stress urinary incontinence: clinical results after 1-year follow-up

Development and application of statistical models for medical scientific researc

Characterizing Electron Temperature Gradient Turbulence Via Numerical Simulation

Numerical simulations of electron temperature gradient (ETG) turbulence are presented which characterize the ETG fluctuation spectrum, establish limits to the validity of the adiabatic ion model often employed in studying ETG turbulence, and support the tentative conclusion that plasmaoperating regimes exist in which ETG turbulence produces sufficient electron heat transport to be experimentally relevant. We resolve prior controversies regarding simulation techniques and convergence by benchmarking simulations of ETG turbulence from four microturbulence codes, demonstrating agreement on the electron heat flux, correlation functions, fluctuation intensity, and rms flow shear at fixed simulation cross section and resolution in the plane perpendicular to the magnetic field. Excellent convergence of both continuum and particle-in-cell codes with time step and velocity-space resolution is demonstrated, while numerical issues relating to perpendicular (to the magnetic field) simulation dimensions and resolution are discussed. A parameter scan in the magnetic shear, s, demonstrates that the adiabatic ion model is valid at small values of s (s < 0.4 for the parameters used in this scan) but breaks down at higher magnetic shear. A proper treatment employing gyrokinetic ions reveals a steady increase in the electron heat transport with increasing magnetic shear, reaching electron heat transport rates consistent with analyses of experimental tokamak discharges

User Evaluation of Neonatology Ward Design: An Application of Focus Group and Semantic Differential

[EN] Objective: The object of this article is to identify the set of affective and emotional factors behind users assessments of a space in a neonatology unit and to propose design guidelines based on these. Background: The importance of the neonatology service and the variety of users place great demands on the space at all levels. Despite the repercussions, the emotional aspects of the environment have received less attention. Methods: To avoid incurring limitations in the user mental scheme, this study uses two complementary methodologies: focus group and semantic differential. The (qualitative) focus group methodology provides exploratory information and concepts. The (quantitative) semantic differential methodology then uses these concepts to extract the conceptual structures that users employ in their assessment of the space. Of the total 175 subjects, 31 took part in focus groups and 144 in semantic differential. Results: Five independent concepts were identified: privacy, functionality and professional nature, spaciousness, lighting, and cleanliness. In relation to the importance of the overall positive assessment of the space, the perception of privacy and sensations of dominance and pleasure are fundamental. Six relevant design aspects were also identified: provide spacious surroundings, facilitate sufficient separation between the different posts or cots, use different colors from those usually found in health-care centers, as some aversion was found to white and especially green, design areas with childhood themes, use warm artificial light, and choose user-friendly equipment. Conclusions: Results provide design recommendations of interest and show the possibilities offered by combining both systems to analyze user response.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Ministerio de Economia y Competitividad, Spain (Project TIN2013-45736-R).Higuera-Trujillo, JL.; Montañana I Aviñó, A.; Llinares Millán, MDC. (2017). User Evaluation of Neonatology Ward Design: An Application of Focus Group and Semantic Differential. HERD Health Environments Research & Design Journal. 10(2):23-48. https://doi.org/10.1177/1937586716641275S234810