44 research outputs found
Ansprüche an Gebäude von morgen - Integration intelligenter Systeme
Die technische Entwicklung, insbesondere auf dem Gebiet der Digitaltechnik eröffnet heute neue und sehr weitreichende Möglichkeiten für die Automatisierung in Zweck- und Wohnbauten. Die zur Verfügung stehenden technischen Komponenten (intelligente Sensoren und Aktoren sowie ein hausinternes Netz für die Datenübertragung -Feldbus-) unterscheiden sich für diese Einsatzfälle kaum. Die Zielstellungen sind jedoch gänzlich andere. Intelligenz im Wohnbau bedeutet vor allem intelligente Alltagsbewältigung (z.B. Zeiteinsparung), Komfort und Wohlbefinden. Daß im Heimbereich nichtfunktionale Faktoren (Human Interface, Ästhetik, Preis, Attraktivität) eine große Rolle spielen, ist in das Problembewußtsein der Gerätehersteller und Käufer getreten. Im Bereich der Heimautomatisierung werden zunehmend moderne, die Möglichkeiten der konventioellen Steuerungs- und Regelungstechnik ergänzende Technologien wie Fuzzy- Steuerungen zur Optimierung der internen Arbeitsweise von Geräten eingesetzt. Die informatorische Vernetzung im Wohnbau unterstützt darüberhinaus wichtige Anliegen des Gebäudemanagements (energetische, ergonomische und ökologische Betrachtungen der Gebäudenutzung unter wirtschaftlichen Gesichtspunkten)
Ansprüche an Gebäude von morgen - Integration intelligenter Systeme
Die technische Entwicklung, insbesondere auf dem Gebiet der Digitaltechnik eröffnet heute neue und sehr weitreichende Möglichkeiten für die Automatisierung in Zweck- und Wohnbauten. Die zur Verfügung stehenden technischen Komponenten (intelligente Sensoren und Aktoren sowie ein hausinternes Netz für die Datenübertragung -Feldbus-) unterscheiden sich für diese Einsatzfälle kaum. Die Zielstellungen sind jedoch gänzlich andere. Intelligenz im Wohnbau bedeutet vor allem intelligente Alltagsbewältigung (z.B. Zeiteinsparung), Komfort und Wohlbefinden. Daß im Heimbereich nichtfunktionale Faktoren (Human Interface, Ästhetik, Preis, Attraktivität) eine große Rolle spielen, ist in das Problembewußtsein der Gerätehersteller und Käufer getreten. Im Bereich der Heimautomatisierung werden zunehmend moderne, die Möglichkeiten der konventioellen Steuerungs- und Regelungstechnik ergänzende Technologien wie Fuzzy- Steuerungen zur Optimierung der internen Arbeitsweise von Geräten eingesetzt. Die informatorische Vernetzung im Wohnbau unterstützt darüberhinaus wichtige Anliegen des Gebäudemanagements (energetische, ergonomische und ökologische Betrachtungen der Gebäudenutzung unter wirtschaftlichen Gesichtspunkten)
High resolution propagation-based lung imaging at clinically relevant X-ray dose levels
Absorption-based clinical computed tomography (CT) is the current imaging method of choice in the diagnosis of lung diseases. Many pulmonary diseases are affecting microscopic structures of the lung, such as terminal bronchi, alveolar spaces, sublobular blood vessels or the pulmonary interstitial tissue. As spatial resolution in CT is limited by the clinically acceptable applied X-ray dose, a comprehensive diagnosis of conditions such as interstitial lung disease, idiopathic pulmonary fibrosis or the characterization of small pulmonary nodules is limited and may require additional validation by invasive lung biopsies. Propagation-based imaging (PBI) is a phase sensitive X-ray imaging technique capable of reaching high spatial resolutions at relatively low applied radiation dose levels. In this publication, we present technical refinements of PBI for the characterization of different artificial lung pathologies, mimicking clinically relevant patterns in ventilated fresh porcine lungs in a human-scale chest phantom. The combination of a very large propagation distance of 10.7 m and a photon counting detector with [Formula: see text] pixel size enabled high resolution PBI CT with significantly improved dose efficiency, measured by thermoluminescence detectors. Image quality was directly compared with state-of-the-art clinical CT. PBI with increased propagation distance was found to provide improved image quality at the same or even lower X-ray dose levels than clinical CT. By combining PBI with iodine k-edge subtraction imaging we further demonstrate that, the high quality of the calculated iodine concentration maps might be a potential tool for the analysis of lung perfusion in great detail. Our results indicate PBI to be of great value for accurate diagnosis of lung disease in patients as it allows to depict pathological lesions non-invasively at high resolution in 3D. This will especially benefit patients at high risk of complications from invasive lung biopsies such as in the setting of suspected idiopathic pulmonary fibrosis (IPF)
Determination of nutrient salts by automatic methods both in seawater and brackish water: the phosphate blank
9 páginas, 2 tablas, 2 figurasThe main inconvenience in determining nutrients in seawater by automatic methods is simply solved:
the preparation of a suitable blank which corrects the effect of the refractive index change on the recorded
signal. Two procedures are proposed, one physical (a simple equation to estimate the effect) and the other
chemical (removal of the dissolved phosphorus with ferric hydroxide).Support for this work came from CICYT (MAR88-0245 project) and
Conselleria de Pesca de la Xunta de GaliciaPeer reviewe
Multi-accesspunkt koncept för SCO trafik i ett Bluetooth-baserad radio infrastruktur nätverk
In this paper, we consider a radio infrastructure network (RIN), which consists of Bluetooth Access Points (APs) to provide services to ad hoc users. The RIN inherently supports both voice and data connectivity. Since Bluetooth offers the establishment of Synchronous Circuit-Oriented (SCO) traffic, the concept under study features a low-cost alternative to indoor cellular base stations. However, a single AP can serve a maximum of only three SCO channels and may not be capable of satisfying the voice traffic demands in hot spots. In order to offer more bandwidth in a location with high voice traffic, two or more APs may be placed in the same coverage area. Respective AP clusters will be denoted as Multi APs. Three Multi AP concepts for doing the SCO allocation are presented and discussed. Our findings show that employing Multi APs significantly reduces the blocking probability.Bidraget diskuterar möjligheter hur man kan använda Bluetooth för att bygga mobiltelefonliknande nätverk för röstsamtal. Tjänstekvalitén och dimensionering av sådana system diskuteras. Nyckelorden: Bluetooth, accesspunkt, rösttrafik, spärrsannolikhe
Multi AP concepts for SCO traffic in a Bluetooth based Radio Infrastructure Network
In this paper, we consider a radio infrastructure network (RIN), which consists
of Bluetooth Access Points (APs) to provide services to ad hoc users. The RIN
inherently supports both voice and data connectivity. Since Bluetooth offers
the establishment of Synchronous Circuit-Oriented (SCO) traffic, the concept
under study features a low-cost alternative to indoor cellular base stations.
However, a single AP can serve a maximum of only three SCO channels and may not
be capable of satisfying the voice traffic demands in hot spots. In order to
offer more bandwidth in a location with high voice traffic, two or more APs may
be placed in the same coverage area. Respective AP clusters will be denoted as
Multi APs. Three Multi AP concepts for doing the SCO allocation are presented
and discussed. Our findings show that employing Multi APs significantly reduces
the blocking probability
A Cross-Layer Optimized Scheme and Its Application in Mobile Multimedia Networks With QoS Provision
To cope with the rapid growth of multimedia applications that requires dynamic levels of quality of service (QoS), cross-layer (CL) design, where multiple protocol layers are jointly combined, has been considered to provide diverse QoS provisions for mobile multimedia networks. However, there is a lack of a general mathematical framework to model such CL scheme in wireless networks with different types of multimedia classes. In this paper, to overcome this shortcoming, we therefore propose a novel CL design for integrated real-time/non-real-time traffic with strict preemptive priority via a finite-state Markov chain. The main strategy of the CL scheme is to design a Markov model by explicitly including adaptive modulation and coding at the physical layer, queuing at the data link layer, and the bursty nature of multimedia traffic classes at the application layer. Utilizing this Markov model, several important performance metrics in terms of packet loss rate, delay, and throughput are examined. In addition, our proposed framework is exploited in various multimedia applications, for example, the end-to-end real-time video streaming and CL optimization, which require the priority-based QoS adaptation for different applications. More importantly, the CL framework reveals important guidelines as to optimize the network performance
In press: A Cross-Layer Optimized Scheme and Its Application in Mobile Multimedia Networks With QoS Provision
To cope with the rapid growth of multimedia applications that requires dynamic
levels of quality of service (QoS), cross-layer (CL) design, where multiple
protocol layers are jointly combined, has been considered to provide diverse
QoS provisions for mobile multimedia networks. However, there is a lack of a
general mathematical framework to model such CL scheme in wireless networks
with different types of multimedia classes. In this paper, to overcome this
shortcoming, we therefore propose a novel CL design for integrated
real-time/non-real-time traffic with strict preemptive priority via a
finite-state Markov chain. The main strategy of the CL scheme is to design a
Markov model by explicitly including adaptive modulation and coding at the
physical layer, queuing at the data link layer, and the bursty nature of
multimedia traffic classes at the application layer. Utilizing this Markov
model, several important performance metrics in terms of packet loss rate,
delay, and throughput are examined. In addition, our proposed framework is
exploited in various multimedia applications, for example, the end-to-end
real-time video streaming and CL optimization, which require the priority-based
QoS adaptation for different applications. More importantly, the CL framework
reveals important guidelines as to optimize the network performance