Burstiness predictions based on rough network traffic measurements

To dimension network links, such that they will not become QoS bottle- necks, the peak rate on these links should be known. To measure these peaks on sufficiently small time scales, special measurement tools are needed. Such tools can be quite expensive and complex. Therefore network operators often rely on more cheap, standard tools, like MRTG, which were designed to measure average traffic rates (m) on time scales such as 5 minutes. For estimating the peak traffic rate (p), operators often use simple rules, such as p = α · m. In this paper we describe measurements that we have performed to investigate how well this rule describes the relation between peak and average traffic rate. In addition, we pro- pose some more advanced rules, and compare these to the simple rule mentioned above. The analyses of our measurements, which have been performed on differ- ent kinds of networks, show that our advanced rules more adequately describe the relation between peak and average traffic rate

Silicon micromachined hollow microneedles for transdermal liquid transfer

This paper presents an improved design and fabrication process [ 13 for hollow micro needles with the proper mechanical strength and sharpness to be applied for painless transdermal transfer of liquids. Tests have shown that liquids like blood are drawn into the needle by capillary forces, reducing the need for active pumping. The fabrication method allows different needle shapes like blades and pencils, is robust enough to be applied for largerscale production, and enables the development of a complete micro-TAS for e.g. blood analysis

Most European SPF ‘pasteurella free’ guineapig colonies are Hacmophilus spp antibody positive

During 1993 - 1998 we tested sera of ´'pasteurella free’ guineapigs from 14 SPF breeding units of 8 European breeders by ELISA using whole cell antigens of 4 growth factor independent Pasteurellaceae (Actinoburi/lus-like taxon 5. P. mulluctda, P. pneumatmpica and SP group pasteurella) and 2 V - factor requiring Pasteurellaceae (Haemophilus Sp). Seropositiye guineapigs were detected in all 14 breeding units. The ELISAS performed with Haemophilus antigens detected significantly more positive samples than ELISAs done with non-Haemophihts antigens. In most units Showmg antibody activity against more than one Pasteurellaeeae antigen, median antibody levels detected by Huemophi/ux ELISAS were significantly higher than levels measured by the other assays. In 4 colonies also examined by culture the serological findings were confirmed by growth of Haemophims Sp, but growth factor independent Pasteurellaceae were not detected. Our findings indicate that Eurupeun ‘pasteurella free’ guineapig breeding colonies are very likely infected by V—faetor dependent Pasteurellaeeae (Haemopltilus Sp)

В. Б. Антонович у листах, спогадах та працях Д. І. Багалія

The previous interglacial (Eemian, 130–114 kyr BP) had a mean sea level highstand 4 to 7 m above the current level, and, according to climate proxies, a 2 to 6 K warmer Arctic summer climate. Greenland ice cores extending back into the Eemian show a reduced depletion in δ18O of about 3‰ for this period, which suggests a significant warming of several degrees over the Greenland ice sheet. Since the depletion in δ18O depends, among other factors, on the condensation temperature of the precipitation, we analyze climatological processes other than mean temperature changes that influence condensation temperature, using output of the regional climate model RACMO2. This model is driven by ERA-40 reanalysis and ECHO-G GCM boundaries for present-day, preindustrial and Eemian climate. The processes that affect the condensation temperature of the precipitation are analyzed using 6-hourly model output. Our results show that changes in precipitation seasonality can cause significant changes of up to 2 K in the condensation temperature that are unrelated to changes in mean temperature

Coupling of climate models and ice sheet models by surface mass balance gradients: application to the Greenland Ice Sheet

It is notoriously difficult to couple surface mass balance (SMB) results from climate models to the changing geometry of an ice sheet model. This problem is traditionally avoided by using only accumulation from a climate model, and parameterizing the meltwater run-off as a function of temperature, which is often related to surface elevation (<i>H</i><sub>s</sub>). In this study, we propose a new strategy to calculate SMB, to allow a direct adjustment of SMB to a change in ice sheet topography and/or a change in climate forcing. This method is based on elevational gradients in the SMB field as computed by a regional climate model. Separate linear relations are derived for ablation and accumulation, using pairs of <i>H</i><sub>s</sub> and SMB within a minimum search radius. The continuously adjusting SMB forcing is consistent with climate model forcing fields, also for initially non-glaciated areas in the peripheral areas of an ice sheet. When applied to an asynchronous coupled ice sheet – climate model setup, this method circumvents traditional temperature lapse rate assumptions. Here we apply it to the Greenland Ice Sheet (GrIS). Experiments using both steady-state forcing and glacial-interglacial forcing result in realistic ice sheet reconstructions