281 research outputs found

    Konfigurering och ibruktagning av KNX system

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    Detta examensarbete behandlar grunderna i KNX samt programmering av KNX enheter med datorprogrammet ETS 4. I arbetet beskrivs hur KNX systemet fungerar, hur det är uppbyggt och de olika överföringsmedium som kan användas då KNX enheter kommunicerar. Jag beskriver också hur ETS 4 installeras på datorn och hur man kommer igång med programmeringen av KNX enheterna. Inför detta examensarbete har jag studerat en del av ABB:s KNX enheter samt deras funktioner och konfigurationsmöjligheter. Syftet med detta examensarbete är att skapa en liten handbok för hur ett KNX system är uppbyggt samt hur KNX enheterna programmeras med ETS 4.Tämä opinnäytetyö käsittelee KNX:n perusteita ja KNX-laitteiden ohjelmointia ETS 4 tietokoneohjelman avulla. Työssä kuvaillaan, miten KNX-järjestelmä toimii, millä tavalla se on rakennettu sekä mitä eri siirtomedioita voidaan käyttää KNX-laitteiden viestinnässä. Työssä kuvaillaan myös, miten ETS-ohjelma asennetaan tietokoneella ja miten päästään aloittamaan KNX-laitteiden ohjelmointi. Ennen tätä opinnäytetyötä kirjoittaja on opiskellut ABB:n KNX-laitteita sekä niiden toimintoja ja konfiguraatiomahdollisuuksia. Opinnäytetyön tarkoituksena on tehdä pieni käsikirja, joka kertoo, miten KNX- järjestelmä on rakennettu sekä millä tavalla KNX-laitteet ohjelmoidaan ETS 4:llä.In this thesis I deal with the basics of KNX as well as the programming of KNX devices with the computer software ETS 4. In the thesis I describe how the KNX system works, how it is built and the different communication media that are used for communication between KNX devices. I also describe how ETS 4 is installed on a personal computer and how to get started with the programming of the KNX devices. When preparing for this thesis I studied a part of ABB’s KNX devices, their functions as well as their configuration possibilities. The purpose of this thesis is to create a small manual that can be used to see how a KNX system is built and to check how KNX devices are programmed with ETS 4

    Proton Irradiation Experiment for the X-ray Charge-Coupled Devices of the Monitor of All-sky X-ray Image mission onboard the International Space Station: I. Experimental Setup and Measurement of the Charge Transfer Inefficiency

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    We have investigated the radiation damage effects on a CCD to be employed in the Japanese X-ray astronomy mission including the Monitor of All-sky X-ray Image (MAXI) onboard the International Space Station (ISS). Since low energy protons release their energy mainly at the charge transfer channel, resulting a decrease of the charge transfer efficiency, we thus focused on the low energy protons in our experiments. A 171 keV to 3.91 MeV proton beam was irradiated to a given device. We measured the degradation of the charge transfer inefficiency (CTI) as a function of incremental fluence. A 292 keV proton beam degraded the CTI most seriously. Taking into account the proton energy dependence of the CTI, we confirmed that the transfer channel has the lowest radiation tolerance. We have also developed the different device architectures to reduce the radiation damage in orbit. Among them, the ``notch'' CCD, in which the buried channel implant concentration is increased, resulting in a deeper potential well than outside, has three times higher radiation tolerance than that of the normal CCD. We then estimated the charge transfer inefficiency of the CCD in the orbit of ISS, considering the proton energy spectrum. The CTI value is estimated to be 1.1e-5 per each transfer after two years of mission life in the worse case analysis if the highest radiation-tolerant device is employed. This value is well within the acceptable limit and we have confirmed the high radiation-tolerance of CCDs for the MAXI mission.Comment: 17 pages, 2 table, 12 figures. Accepted for publication of Japanese Journal of Applied Physics. High resolution file is available from http://wwwxray.ess.sci.osaka-u.ac.jp/~miyata/paper/proton_cti.pd

    Mental fatigue caused by prolonged cognitive load associated with sympathetic hyperactivity

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    <p>Abstract</p> <p>Background</p> <p>It is known that chronic fatigue is associated with sympathetic hyperactivity. However, the relationship between autonomic function and mental fatigue caused by a prolonged mental load in healthy humans is still unclear. Thus, in order to clarify the mechanisms underlying mental fatigue, we examined the association between mental fatigue and autonomic functions.</p> <p>Methods</p> <p>The study group comprised 10 healthy participants. To induce mental fatigue, participants performed mental tasks, which consisted of the advanced trail making test, <it>kana </it>pick-out test and mirror drawing test, for 8 hr, corresponding to a normal work day. Autonomic functions were measured by accelerated plethysmography before and after the fatigue-inducing mental tasks. As a control, the same participants completed an 8-hr relaxation session 4 weeks before the fatigue session.</p> <p>Results</p> <p>After the 8-hr relaxation session, low-frequency component power (LF), high-frequency component power (HF) and low-frequency component power/high-frequency component power ratio (LF/HF ratio) were not changed from baseline. In contrast, after the fatigue session, the HF and LF/HF ratio were significantly changed from baseline; specifically, the HF was lower and LF/HF ratio was higher as compared to those after the relaxation session.</p> <p>Conclusions</p> <p>Sympathetic hyperactivity based on decreased parasympathetic activity is associated with mental fatigue induced by prolonged cognitive load.</p

    Stable C and N isotope abundances in water-extractable organic matter from air-dried soils as potential indices of microbially utilized organic matter

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    Stable carbon (C) and nitrogen (N) isotopes (13C and 15N) in water-extractable organic matter (WEOM) derived from air-dried soils may be applicable to elucidate the microbial decomposition of soil organic matter (SOM), which is crucial in terrestrial C cycles. A total of 40 soil samples were collected from a depth of 0–6 cm from a temperate broadleaved forest in Japan with vegetation succession from grassland approximately 150 years ago. Those soil samples were air-dried before the water extraction process and organic matter analysis. The C and N concentrations of WEOM were &lt;3.6% of those of the bulk soil and were positively correlated with those of the bulk soil at a p-value of &lt; 0.01. A positive correlation between the two fractions (i.e., WEOM and bulk soils) was also found for natural 13C and 15N abundances (δ13C and δ15N; p &lt; 0.01). However, the C/N ratio of WEOM was slightly correlated with that of bulk soils, exhibiting a narrow range of values of ~10. Thus, those features of the WEOM were similar to the well-known features of microbial biomass. The δ13C and δ15N enrichments in WEOM relative to bulk soil, the difference in stable isotope abundances between bulk SOM and WEOM were negatively and positively correlated, respectively, with the concentrations of organo-mineral complexes and short-range order minerals (non-crystalline oxyhydroxides of aluminum and iron, allophane, imogolite, and allophane-like constituents), which play significant roles in SOM stabilization in soils. These relationships suggest that the stable isotopic enrichments in WEOM can be a good indicator of the microbial utilization of soil C and N under different substrate availabilities, which are crucial to SOM decomposition and decomposability substantially varying from local to global scales

    Influence of expanding and contracting magnetic field configurations on detached plasma formation in a linear plasma device

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    We investigated the effects of magnetic field structure on detached plasma formation by simulating magnetically expanding and contracting plasma in a linear plasma device. The present study helps to characterize the geometries of a conventional poloidal divertor and advanced divertors, e.g., super-X divertor. The total ion particle flux measured with a large-diameter target plate dramatically changed under the detached plasma condition compared to that in attached plasma. Under the detached plasma condition, the magnetically expanding plasma clearly exhibited a significant influence on the degradation of detached plasma formation. Further, the magnetically contracting plasma slightly enhanced the electron-ion recombination (EIR) processes. By changing the magnetic field structure from contraction to expansion, the electron density (ne) decreased and the electron temperature (Te) increased upstream from the recombination front, leading to the degradation of the EIR processes. The effect of the decrease in parallel flow velocity under the magnetically contracting plasma on the plasma detachment was not observed because the driven flow due to pressure gradient compensated the effect

    LHDヘリカル閉ダイバータのための新コンセプト真空容器内クライオソープションポンプの開発

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    The in-vessel cryo-sorption pump for the Closed Helical Divertor (CHD) in the Large Helical Device (LHD) has been developed at the National Institute for Fusion Science (NIFS). An organic adhesive-free bonding technique for attaching activated carbon pellets to a copper cold panel was invented, which employs the indium solder with intermediate materials. The prototype of the CHD with the newly developed cryo-sorption pump was installed in the LHD. Performance of the cryo-sorption pump was estimated in the LHD vacuum vessel. A satisfactory result of the maximum pumping speed up to 9 m3/s was obtained with one divertor module in one toroidal section (10% of the torus), which is equivalent to the required pumping speed of the CHD

    Blob/Hole Generation in the Divertor Leg of the Large Helical Device

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    We have analyzed ion saturation current fluctuation measured by a fast scanning Langmuir probe (FSP) in edge region of the Large Helical Device (LHD). Positive and negative spikes of the ion saturation current were observed in the private region and on the divertor leg, respectively. It was found that the boundary position between these regions corresponds to the low-field side (LFS) edge of the divertor leg where the gradient of the ion saturation current profile was the maximum. Such a positional relationship resembles that near the separatrix in the LFS in tokamaks, where blobs and holes are generated. Statistical analysis indicates similar fluctuation characteristics among different magnetic devices
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