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31.
This study investigates the stable isotopic composition of dissolved inorganic carbon (DIC), expressed as δ13CDIC, in domestic and foreign bottled waters randomly collected on the Slovene market. All together 58 brands and 16 replicates were analysed. The δ13CDIC values varied between −63.1‰ and +1.0‰ with an average of −12.3‰. Average δ13CDIC values for naturally sparkling, artificially sparkling, still and flavoured waters were −3.3‰, −36.5‰, −10.0‰ and −11.0‰, respectively. The lowest values are characteristic of artificial sparkling waters (minimum −63.1‰) and can be attributed to injection of industrial CO2 during bottled water production. Therefore, determination of the isotopic composition of DIC can represent a useful analytical tool to distinguish between natural and artificially sparkling waters. Furthermore, the method used enabled determination of the various origins of still waters. From the bottled waters sampled it was possible to discern waters that originate from deeper aquifers, from aquifers in equilibrium with soil CO2, or from aquifers with their recharge in a mountainous area. Finally, δ13CDIC values of flavoured waters illustrate that isotopic fractionation occurs during the production process and that δ13CDIC values in products of some producers have a large variation. 相似文献
32.
Analysis and Provision of QoS for Distributed Grid Applications 总被引:5,自引:0,他引:5
Rashid?J.?Al-AliEmail author Kaizar?Amin Gregor?von?Laszewski Omer?F.?Rana David?W.?Walker Mihael?Hategan Nestor?Zaluzec 《Journal of Grid Computing》2004,2(2):163-182
Grid computing provides the infrastructure necessary to access and use distributed resources as part of virtual organizations. When used in this way, Grid computing makes it possible for users to participate in collaborative and distributed applications such as tele-immersion, visualization, and computational simulation. Some of these applications operate in a collaborative mode, requiring data to be stored and delivered in a timely manner. This class of applications must adhere to stringent real-time constraints and Quality-of-Service (QoS) requirements. A QoS management approach is therefore required to orchestrate and guarantee the timely interaction between such applications and services. We discuss the design and a prototype implementation of a QoS system, and demonstrate how we enable Grid applications to become QoS compliant. We validate this approach through a case study of an image processing task derived from a nanoscale structures application. 相似文献
33.
Joško Valentinčič Mihael Junkar 《The International Journal of Advanced Manufacturing Technology》2007,33(7-8):698-705
To achieve a high removal rate and low electrode wear in a sinking electrical discharge machining process (EDM), rough machining
parameters have to be selected according to the size of the eroding surface. In general, the size of the eroding surface varies
according to the depth of the machining. Thus, it has to be determined on-line. This paper shows that the electric current
signal in the gap depends on the size of the eroding surface. The significance of the process attributes of the electric current
signal is established by inductive machine learning and the general decision rules are derived. The size of the eroding surface
can be detected on-line by monitoring and evaluating the electric current signal in the gap. 相似文献