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71.
Andreas Schrader Darren V. Carlson Dominik Busch 《Personal and Ubiquitous Computing》2008,12(4):299-306
In this paper we describe a novel approach for interactive cinema based on context-aware narration using handheld computers.
The paper describes both the artistic approach and the ubiquitous computing framework developed to realize the scenario. This
framework has been used in various projects, including the described video production course at the ISNM, where five interactive
cinema concepts have been developed and shown during a public demonstration. In our approach, a new type of user experience
has been established by placing the viewer inside the movie’s physical locations during playback. Moreover, the developed
ubiquitous computing framework provides a foundation for future work in the area of ad-hoc, service-oriented Ubicomp scenarios. 相似文献
72.
73.
Gunter Schneider Hartmut Maier Dominik Schlipf 《能源与动力工程:英文版》2014,(5):876-881
In order to optimize the electricity yield of CSP (concentrated solar power) plants, TES (thermal energy storage) systems are regarded as an essential component. Furthermore, for many electricity grid operators, it is important to have spinning reserves in the grid and dispatchable power available, both offered by CSP-plants with integrated thermal energy storage. Enolcon is developing a new TES-system since several years. The system itself was designed to offer a principle simple and robust setup (with regard to execution and operation) and which is reducing the electricity costs of CSP-power plants by the consequent use of state of the art technology. Furthermore, such system shall be open to future developments of CSP-systems with regard to increasing steam temperatures and steam pressure. Such TES-system shall be commercially available for large scale application already in year 2014/2015. The key elements of the enolcon-TES are the open cycle using always ambient air with an air-air-heat exchanger and the arrangement of the storage material in such way to minimize the pressure losses and the own electricity consumption. The development is progressing in a structured way by studies, engineering works, TES-pilot plants, isothermal air flow test plant for the verification of the CFD-calculations, and since end of 2012 by the operation of a high temperature TES-module with all features of the large scale modules. 相似文献
74.
This paper describes the technological status of and some challenges in the manufacturing of Cu(In,Ga)Se2 (CIGS)-based solar cells on flexible polymer and metal substrates. Substrate characteristics such as thermal expansion properties and stability, surface roughness, or substrate composition, strongly influence growth and properties of the following layers. For example, adhesion failure, cracking, or contamination by diffusion of impurities from the substrate may occur with some substrates. Aspects of (external) sodium incorporation into CIGS are discussed for high and low CIGS deposition temperature. Low-temperature deposition processes are particularly important when polyimide substrates are used. The electrical insulation of metal foils by dielectric barriers (e.g. SiOx or Al2O3) allows the fabrication of monolithically integrated modules. A soft and selective patterning technique based on laser scribing and mask-free photolithography is described. Working modules as large as 20 cm × 30 cm were achieved with these methods. 相似文献
75.
NN Biswas SJ Ting MC Mattingly JM Bishop NM Cason VP Kenney RC Ruchti WD Shephard WW Neale PA Elcombe MJ Goodrick JC Hill W Kowald WD Walker P Lucas L Voyvodic R Ammar D Coppage R Davis D Day J Gress S Kanekal N Kwak L Herder J Whitmore RA Lewis BY Oh GA Smith W Toothacker 《Canadian Metallurgical Quarterly》1986,33(11):3167-3171
76.
Jean-Luc Loizeau Michel Pardos Fabrice Monna Christophe Peytremann Laurence Haller Janusz Dominik 《Lakes & Reservoirs: Research and Management》2004,9(1):53-63
The Bay of Vidy is the most contaminated area of Lake Geneva, Switzerland, as a result of the release of treated and untreated waste water from the municipal sewage treatment plant of the city of Lausanne and its surroundings. The reconstruction of the historical deposition of heavy metals in the sediment of the bay has been performed by the analysis of several dated (radiocaesium) sediment cores. The presence of sewage‐derived contaminants in the Bay of Vidy since the beginning of the sewage treatment plant's operations in 1964 is clearly observed, when a sharp increase in heavy metal contents is recorded, with maximum concentrations of cadmium, copper, zinc and lead occurring between the late 1960s and early 1970s. Despite considerable improvement in recent times, the present concentrations of the investigated heavy metals in sediments of the Bay of Vidy are still higher than concentrations measured at the centre of the lake, the latter close to Lake Geneva's natural background values. It is concluded that the quantity of heavy metals deposited in the bay is considerable and, because of sediment instability, will constitute a potential hazard for biota. 相似文献
77.
Walter Wildi Janusz Dominik Jean-Luc Loizeau Richard Linn Thomas Pierre-Yves Favarger Laurence Haller Antoine Perroud Christophe Peytremann 《Lakes & Reservoirs: Research and Management》2004,9(1):75-87
This paper quantifies sediment contamination by heavy metals in four reservoirs and one lake located downstream from major urban areas in Switzerland. The waterbodies include the Wettingen Reservoir (located on the Limmat River downstream from Zürich), the Klingnau Reservoir (on the lower Aare River), the Wohlen Reservoir (downstream from Berne), the Verbois Reservoir (downstream from Geneva) and Vidy Bay (Lake Geneva, city of Lausanne). For all sediment cores and contaminants, a trend is observed from high contaminant values in the lower part of the cores, decreasing to lower concentrations in the upper part of the cores. However, for each site and each element, specific features are recognized. Applying the criteria of the Swiss ordinance on soil protection, all sediment cores must be classified as contaminated by one or more contaminants and at variable levels. From these data, it is concluded that: reservoirs and lakes located downstream from major urban centres in Switzerland have accumulated significant volumes of contaminated sediments in the past, representing the largest, but not the most intensely, contaminated sites on a national scale; the main environmental risk is remobilization of the contaminants and their return to the food chain, particularly by infiltration into the groundwater; and although the processes of remobilization are identified, the conditions of occurrence and the amplitude of the processes are still poorly known. Different options of reservoir and lake sediment management also are discussed and further research topics defined. 相似文献
78.
79.
Prof. Dr.-Ing habil. Dominik Surek Prof. Dr.-Ing. habil. Gerd Grabow Dr.-Ing. H. H. Henning 《Forschung im Ingenieurwesen》1995,61(9):233-240
Zusammenfassung Im Resonator von Laseranlagen werden ca. 20% der zugeführten Energie für den Laserstrahl genutzt. 80% der zugeführten Gesamtenergie
werden mit dem Lasergas ungenutzt aus dem Resonator in den nachfolgenden W?rmeübertrager abgeführt. Um den Anlagenwirkungsgrad
von Laseranlagen zu erh?hen, soll die ungenutzte Austrittsenergie aus dem Resonator in einer nachgeschalteten Entspannungsturbine
in mechanische Energie umgesetzt werden, die zum Antrieb des Lasergasverdichters genutzt wird. Dadurch kann der Verdichter
mit der vorhandenen Proze?energie angetrieben werden und der Anlagenwirkungsgrad vonη
A
bis 0,20 aufη
A
bis 0,34 erh?ht werden. Durch thermodynamische Proze?untersuchungen werden die erreichbaren Wirkungsgradsteigerungen von
Laseranlagen ausgewiesen und die optimalen Parameterbereiche für die Druck-und Temperaturverh?ltnisse ermittelt. Das Leistungsverh?ltnis
der gewonnenen Turbinenleistung zur notwendigen Verdichterleistung wird angegeben. 相似文献
80.
Prof. Dr.-Ing. habil. Dominik Surek Dipl.-Ing. Hubertus Galinsky 《Forschung im Ingenieurwesen》1995,61(5):117-128
Zusammenfassung Seitenkanalverdichter unterliegen trotz ihrer geringen Druckverh?ltnisse im Teillastbereich erheblichen thermischen Belastungen.
Dadurch steigt nicht nur die Verdichtungsendtemperatur und die Maschinenbelastung, sondern mit steigender Maschinentemperatur
erfolgt auch eine erhebliche Aufheizung des Gases bereits im Eintrittsbereich, wodurch die Arbeitsübertragung beeinflu?t wird.
Die Resultate experimenteller Untersuchungen zeigen, da? die Aufheizung des Gases besonders im Eintrittsbereich des Seitenkanals
erfolgt und dadurch die Arbeitsübertragung im vorderen Bereich stark verlustbehaftet erfolgt. Die Folge davon sind sehr hohe
Polytropenexponenten bei gro?en Druckverh?ltnissen im Teillastbereich, die zu einer gro?en W?rmezufuhr an das Gas führen und
den Wirkungsgrad der Maschinen mindern. 相似文献