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991.
992.
Helmut Prendinger Marc Miska Kugamoorthy Gajananan Alfredo Nantes 《Computer-Aided Civil and Infrastructure Engineering》2014,29(7):480-495
The article introduces a novel platform for conducting controlled and risk‐free driving and traveling behavior studies, called Cyber‐Physical System Simulator (CPSS). The key features of CPSS are: (1) simulation of multiuser immersive driving in a three‐dimensional (3D) virtual environment; (2) integration of traffic and communication simulators with human driving based on dedicated middleware; and (3) accessibility of multiuser driving simulator on popular software and hardware platforms. This combination of features allows us to easily collect large‐scale data on interesting phenomena regarding the interaction between multiple user drivers, which is not possible with current single‐user driving simulators. The core original contribution of this article is threefold: (1) we introduce a multiuser driving simulator based on DiVE, our original massively multiuser networked 3D virtual environment; (2) we introduce OpenV2X, a middleware for simulating vehicle‐to‐vehicle and vehicle‐to‐infrastructure communication; and (3) we present two experiments based on our CPSS platform. The first experiment investigates the “rubbernecking” phenomenon, where a platoon of four user drivers experiences an accident in the oncoming direction of traffic. Second, we report on a pilot study about the effectiveness of a Cooperative Intelligent Transport Systems advisory system. 相似文献
993.
994.
Effect of lactic acid bacteria inoculants on in vitro digestibility of wheat and corn silages 总被引:2,自引:0,他引:2
Weinberg ZG Shatz O Chen Y Yosef E Nikbahat M Ben-Ghedalia D Miron J 《Journal of dairy science》2007,90(10):4754-4762
The aim of the study was to determine the effect of 10 sources of lactic acid bacteria (LAB) on dry matter digestibility (DM-D) and neutral detergent fiber digestibility (NDF-D), in various combinations with starch, in vitro. The soluble starch represented a concentrate feed, whereas silage represented feeding only roughage. The DM-D and NDF-D were determined after 24 and 48 h of incubation to represent effective (24 h) and potential (48 h) digestibility. Addition of LAB was both by direct application of the inoculants to rumen fluid (directly fed microbials) and by the use of preinoculated silages. For each feed combination, tubes without added LAB served as controls. The results indicate that, overall, some LAB inoculants applied at ensiling or added directly to the rumen fluid had the potential to increase the DM-D and NDF-D. The major significant inoculant effect on NDF-D was obtained after 24 h of incubation, whereas the effect after 48 h was mainly nonsignificant. The effective inoculants seemed to minimize the inhibitory effect of the starch on NDF-D within 24 h, perhaps by competition with lactate-producing rumen microorganisms. 相似文献
995.
Helmut Starke Karl Herrmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1976,228(4):131-135
In schwarzen Johannisbeeren nahm der Gehalt an Glykosiden des Quercetins und besonders des Myricetins während der Reife sehr stark zu. Auch in Kulturheidelbeeren war der Gehalt an Myricetin und in Ligusterbeeren an Quercetin in reifen Früchten höher als in unreifen. Dagegen wiesen die meisten reifen Früchte (z. B. rote und weiße Johannisbeeren, Sauerkirschen, Pflaumen, Kulturheidelbeeren, schwarze Holunderbeeren) eine niedrigere Konzentration an Glykosiden des Kämpferols und Quercetins als unreife auf. Anthocyaninbildung ist also meist nicht mit einer Anhäufung von Flavonolen (vielleicht mit Ausnahme des Myricetins) verbunden. 相似文献
996.
Helmut K. Mayer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1996,202(6):465-470
We have established an electrophoretic method to evaluate proteolysis in Parmesan cheese by means of an objective ripening index. The separation of caseins by alkaline polyacrylamide gel electrophoresis (PAGE) (12% T, 2.6% C, pH 8.9, 5 M urea) is followed by the densitometric analysis of the- and-casein fractions. The relationship between the resulting coefficients (-Cn/-Cn) and the age of reference samples of Original Italian Grana Padano (6–22 months) was linear up to 15 months, allowing an evaluation of the extent of proteolysis and therefore a deduction of the age of the Parmesan samples analysed. Based on this calibration we propose to use a threshold level of 1.3 (-Cn/-Cn) to verify the required age, i.e. 12 months, of Parmesan cheese, retailed as a loaf or prepacked slices. Commercially grated Parmesan samples may contain 20% cheese rind, which has a very low degree of casein breakdown. So a threshold level of 0.8 (-Cn/-Cn) is proposed for all grated Parmesan products. The preparation of reference solutions with defined coefficients (-Cn/-Cn), corresponding to the proteolysis indices of reference samples of different aged Grana Padano is described. The coefficients (-Cn/-Cn) as well as the-casein content of two additional series of reference samples and of 49 commercial Parmesan samples taken from retail outlets in Austria and Italy are presented. 相似文献
997.
Helmut Steuerle 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1979,169(6):429-434
Zusammenfassung Es wird eine Methode zur Bestimmung von sauren Farbstoffen beschrieben, bei der Anreicherung und Chromatographic an einer HPLC-Säule durchgeführt werden. Dabei wird ein relativ großes Volumen der wäßrigen Probe direkt auf die Säule aufgetragen unter Bedingungen, unter denen der Farbstoff nicht wandert und am Kopf der Säule in einer schmalen Zone festgehalten wird. Nach Auswaschen der Verunreinigungen wird der Farbstoff dann mit einem Elutionsmittelgradienten chromatographiert. Die Methode kann angewandt werden zur Bestimmung von Spuren saurer Farbstoffe beim Fischakkumulationstest im Rahmen toxikologischer Prüfungen von chemischen Substanzen und zwar sowohl im Fischfleisch (nach Aufschluß) wie auch im Aquarienwasser, ferner bei der Bestimmung saurer Lebensmittelfarbstoffe in Lebensmitteln.
Herrn Prof. Dr. Matthias Seefelder zum 60. Geburtstag gewidmet 相似文献
Enrichment, identification and determination of acid dyes by HPLC with special reference to food dyes
Summary A method is described for determining acid dyes in which enrichment and chromatography are carried out on an HPLC column. A relatively large volume of the aqueous sample is applied to the column direct under conditions under which the dye does not migrate and is held in a narrow zone at the head of the column. After the impurities have been washed out, the dye is chromatographed with an elution gradient. The method can be used for determining traces of acid dyes in the fish accumulation test in connection with the toxicological investigations of chemical compounds both in the fish meat (after digestion) and in aquarium water and also for determining acid dyes in food.
Herrn Prof. Dr. Matthias Seefelder zum 60. Geburtstag gewidmet 相似文献
998.
Snow-Cover Parameters Retrieved from Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) Data 总被引:6,自引:0,他引:6
Kunzi Klaus F. Patil Subash Rott Helmut 《Geoscience and Remote Sensing, IEEE Transactions on》1982,(4):452-467
The Nimbus-7 satellite launched on October 24, 1978, carries a multifrequency, dual-polarized microwave imager. The instrument is designed to sense the ocean surface, the atmosphere, and land surfaces remotely. From previous ground-based and satellite-based microwave experiments, it is well known, that snow cover over land has a very distinct effect on the microwave signatures of the earth surface. It was the goal of this study to show that the three snow-cover parameters: extent, snow water equivalent, and onset of snow melt can be determined using scanning multichannel microwave radiometer (SMMR) data. Our analysis has shown, that the three snow parameters mentioned above are retrievable with sufficient accuracy to be of great value in climatology, meteorology, and hydrology. Snow extent is determined for dry snow cover with depth ?5 cm, snow water equivalent can be determined on a regional basis with ?2 g/cm2 rms accuracy, and the onset of snow melt is clearly visible by the detection of melt and refreeze cycles prior to snow runoff. The algorithms derived are simple enough to be incorporated in fully automated operational data analysis schemes. 相似文献
999.
Mihai Irimia‐Vladu Pavel A. Troshin Melanie Reisinger Lyuba Shmygleva Yasin Kanbur Günther Schwabegger Marius Bodea Reinhard Schwödiauer Alexander Mumyatov Jeffrey W. Fergus Vladimir F. Razumov Helmut Sitter Niyazi Serdar Sariciftci Siegfried Bauer 《Advanced functional materials》2010,20(23):4069-4076
Biocompatible‐ingestible electronic circuits and capsules for medical diagnosis and monitoring are currently based on traditional silicon technology. Organic electronics has huge potential for developing biodegradable, biocompatible, bioresorbable, or even metabolizable products. An ideal pathway for such electronic devices involves fabrication with materials from nature, or materials found in common commodity products. Transistors with an operational voltage as low as 4–5 V, a source drain current of up to 0.5 μA and an on‐off ratio of 3–5 orders of magnitude have been fabricated with such materials. This work comprises steps towards environmentally safe devices in low‐cost, large volume, disposable or throwaway electronic applications, such as in food packaging, plastic bags, and disposable dishware. In addition, there is significant potential to use such electronic items in biomedical implants. 相似文献
1000.