Simulation System for the Wendelstein 7-X Safety Control System

The Wendelstein 7-X (W7-X) Safety Instrumented System (SIS) ensures personal safety and investment protection. The development and implementation of the SIS are based on the international safety standard for the process industry sector, IEC 61511. The SIS exhibits a distributed and hierarchical organized architecture consisting of a central Safety System (cSS) on the top and many local Safety Systems (lSS) at the bottom. Each technical component or diagnostic system potentially hazardous for the staff or for the device is equipped with an lSS. The cSS is part of the central control system of W7-X. Whereas the lSSs are responsible for the safety of each individual component, the cSS ensures safety of the whole W7-X device. For every operation phase of the W7-X experiment hard- and software updates for the SIS are mandatory. New components with additional lSS functionality and additional safety signals have to be integrated. Already established safety functions must be adapted and new safety functions have to be integrated into the cSS. Finally, the safety programs of the central and local safety systems have to be verified for every development stage and validated against the safety requirement specification. This contribution focuses on the application of a model based simulation system for the whole SIS of W7-X. A brief introduction into the development process of the SIS and its technical realization will be give followed by a description of the design and implementation of the SIS simulation system using the framework SIMIT (Siemens). Finally, first application experiences of this simulation system for the preparation of the SIS for the upcoming operation phase OP 1.2b of W7-X will be discussed

Pruebas de campo con trampas para atraer las moscas de las frutas (Díptera: Tephritidae) en huertos comerciales de níspero, mamey sapote, y carambola en Puerto Rico.

Field trials in Puerto Rico were conducted to compare the attractiveness of the standard bait of pelletized torula yeast/borax with a two-component (ammonium acetate and putrescine) synthetic lure for Anastrepha spp. within orchards of sapodilla, mamey sapote, and carambola. In addition, the trapping was conducted to provide information on the fruit fly pressure and species composition within these three fruit crops. In sapodilla and mamey sapote, significantly more female and male flies were collected over the entire collection periods in traps containing torula yeast than with the twocomponent synthetic lure. Fruit fly pressure from predominantly A. suspensa within sapodilla was extremely high; in contrast, very few of either species was found in mamey sapote. Within carambola, significantly more flies were captured with the two-component synthetic lure, and the predominant species was A. obliqua. With both lure types, more female flies than males were captured within all fruit plots.Se llevó a cabo un estudio de campo para comparar la efectividad de trampas de levadura torula y trampas sintéticas de acetato de amonio mezclado con putrescina para atraer las moscas de las frutas (Anastrepha) en huertos de níspero, mamey sapote y carambola. El muestreo también se llevó a cabo para obtener información acerca de la presión que ejercen estas moscas de las frutas en estos cultivos. En mamey sapote y níspero, un número significativamente mayor de moscas hembras y machos se recolectaron en trampas de levadura torula que en trampas de acetato de amonio con putrescina. Anastrepha suspensa fue la especie que ejerció mayor presión en huertos de níspero; sin embargo, muy pocas de ésta u otras especies de moscas de las frutas se encontraron en mamey sapote. En huertos de carambola se capturó un número significativamente mayor de moscas de las frutas utilizando la trampa de citrato de amonio con putrescina; la especie predominante fue Anastrepha obliqua. En ambos tipos de trampas se recolectaron más moscas hembras que machos

Research in Progress: On-Farm Storage of Ethanol Co-Products

In the past four years, five new dry-mill ethanol plants have been constructed in the northwest Iowa, and another one is under construction. These six mills will process 82 million bushels of corn to produce 217 million gallons of ethanol and almost 700,000 tons of co-products. In the production of one million gallons of ethanol yearly, almost 9 tons of co-product are produced daily. Consequently, the daily marketing of ethanol co-products is important. Livestock producers, who take delivery of the coproducts on a regular basis, are using various storage methods and management schemes. Unfortunately, research in the storage of dry-mill ethanol co-products on-farm is in its infancy, and there are many questions yet to be addressed. The Department of Animal Science at ISU began this on-farm research to help determine nutritional and storage losses of ethanol co-products stored on-farm. This research involved four on-farm storage trials

A GBT Survey of the HALOGAS Galaxies and Their Environments I: Revealing the full extent of HI around NGC891, NGC925, NGC4414 & NGC4565

We present initial results from a deep neutral hydrogen (HI) survey of the HALOGAS galaxy sample, which includes the spiral galaxies NGC891, NGC925, NGC4414, and NGC4565, performed with the Robert C. Byrd Green Bank Telescope (GBT). The resulting observations cover at least four deg$^2$ around these galaxies with an average 5$\sigma$ detection limit of 1.2$\times$10$^{18}$ cm$^{-2}$ over a velocity range of 20 km s$^{-1}$ and angular scale of 9.1$'$. In addition to detecting the same total flux as the GBT data, the spatial distribution of the GBT and original Westerbork Synthesis Radio Telescope (WSRT) data match well at equal spatial resolutions. The HI mass fraction below HI column densities of 10$^{19}$ cm$^{-2}$ is, on average, 2\%. We discuss the possible origins of low column density HI of nearby spiral galaxies. The absence of a considerable amount of newly detected HI by the GBT indicates these galaxies do not have significant extended diffuse HI structures, and suggests future surveys planned with the SKA and its precursors must go \textit{at least} as deep as 10$^{17}$ cm$^{-2}$ in column density to significantly increase the probability of detecting HI associated with the cosmic web and/or cold mode accretion.Comment: Accepted for publication in The Astrophysical Journal; 28 pages, 15 figure

Collinear helium under periodic driving: stabilization of the asymmetric stretch orbit

The collinear eZe configuration of helium, with the electrons on opposite sides of the nucleus, is studied in the presence of an external electromagnetic (laser or microwave) field. We show that the classically unstable "asymmetric stretch" orbit, on which doubly excited intrashell states of helium with maximum interelectronic angle are anchored, can be stabilized by means of a resonant driving where the frequency of the electromagnetic field equals the frequency of Kepler-like oscillations along the orbit. A static magnetic field, oriented parallel to the oscillating electric field of the driving, can be used to enforce the stability of the configuration with respect to deviations from collinearity. Quantum Floquet calculations within a collinear model of the driven two-electron atom reveal the existence of nondispersive wave packets localized on the stabilized asymmetric stretch orbit, for double excitations corresponding to principal quantum numbers of the order of N > 10.Comment: 13 pages, 12 figure

Lorenz-like systems and classical dynamical equations with memory forcing: a new point of view for singling out the origin of chaos

A novel view for the emergence of chaos in Lorenz-like systems is presented. For such purpose, the Lorenz problem is reformulated in a classical mechanical form and it turns out to be equivalent to the problem of a damped and forced one dimensional motion of a particle in a two-well potential, with a forcing term depending on the ``memory'' of the particle past motion. The dynamics of the original Lorenz system in the new particle phase space can then be rewritten in terms of an one-dimensional first-exit-time problem. The emergence of chaos turns out to be due to the discontinuous solutions of the transcendental equation ruling the time for the particle to cross the intermediate potential wall. The whole problem is tackled analytically deriving a piecewise linearized Lorenz-like system which preserves all the essential properties of the original model.Comment: 48 pages, 25 figure

Analysing Lyapunov spectra of chaotic dynamical systems

It is shown that the asymptotic spectra of finite-time Lyapunov exponents of a variety of fully chaotic dynamical systems can be understood in terms of a statistical analysis. Using random matrix theory we derive numerical and in particular analytical results which provide insights into the overall behaviour of the Lyapunov exponents particularly for strange attractors. The corresponding distributions for the unstable periodic orbits are investigated for comparison.Comment: 4 pages, 4 figure

A Census of the Extended Neutral Hydrogen around 18 MHONGOOSE Galaxies

We present the analysis of the diffuse, low column density H I environment of 18 MHONGOOSE galaxies. We obtained deep observations with the Robert C. Byrd Green Bank Telescope and reached down to a 3σ column density detection limit of NHI = 6.3 × 1017 cm-2 over a 20 km s-1 line width. We analyze the environment around these galaxies, with a focus on H I gas that reaches column densities below NHI = 1019 cm-2. We calculate the total amount of H I gas in and around the galaxies, revealing that nearly all of these galaxies contained excess H I outside of their disks. We quantify the amount of diffuse gas in the maps of each galaxy, defined by H I gas with column densities below 1019 cm-2, and find a large spread in percentages of diffuse gas. However, by binning the percentage of diffuse H I into quarters, we find that the bin with the largest number of galaxies is the lowest quartile (0%-25% diffuse H I). We identified several galaxies that may be undergoing gas accretion onto the galaxy disk using multiple methods of analysis, including azimuthally averaging column densities beyond the disk, and identifying structure within our integrated intensity (moment 0) maps. We measured H I mass outside the disks of most of our galaxies, with rising cumulative flux even at large radii. We also find a strong correlation between the fraction of diffuse gas in a galaxy and its baryonic mass, and we test this correlation using both Spearman and Pearson correlation coefficients. We see evidence of a dark matter halo mass threshold of Mhalo ∼ 1011.1 M⊙ in which galaxies with high fractions of diffuse H I all reside below. It is in this regime that cold-mode accretion should dominate. Finally, we suggest a rotation velocity of vrot ∼ 80 km s-1 as an upper threshold to find diffuse-gas-dominated galaxies