A Survey of Medium Access Mechanisms for Providing QoS in Ad-Hoc Networks

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Impact of volcanic eruptions on the occurrence of PAHs compounds in the aquatic ecosystem of the southern part of West Spitsbergen (Hornsund fjord, Svalbard)

The paper presents changes in concentration levels of dioxin-like compounds that can be observed over the course of four study seasons in water samples collected from the Arctic watershed of Svalbard. The conducted analysis involved anthropogenic and natural factors that may affect the concentration of PAHs in the study samples of water. An attempt is made to indicate the emission source of the compounds being deposited and to identify the extent to which the substances under analysis actually affect the Arctic ecosystems. Moreover, the work employs the following: diagnostic ratios PAHs, air masses backward trajectory analysis, Lidar observations and land relief analysis in order to provide a multi-level interpretation of the obtained data. Natural environment constitutes a complex system of subtle correlations that need to be perceived as a dynamic medium, in which multi-faceted processes take place

Practical analysisof IEEE 802.11b/g cardsin multirate ad hoc mode, Journal of Telecommunications and Information Technology, 2008, nr 1

In multirate ad hoc networks, mobile stations usually adapt their transmission rates to the channel conditions. This paper investigates the behavior of IEEE 802.11b/g cards in a multirate ad hoc environment. The theoretical upper bound estimation of the throughput in multirate ad hoc networks is derived. The measurement scenarios and obtained results are presented. For result validation the theoretical and experimental values are compared. The achieved results, presented in the form of figures, show that cards manufactured by independent vendors perform differently. Therefore, choosing the optimum configuration, according to the user’s requirements, is possible

Providing QoS Guarantees in Broadband Ad Hoc Networks, Journal of Telecommunications and Information Technology, 2011, nr 4

This paper presents a novel QoS architecture for IEEE 802.11 multihop broadband ad hoc networks integrated with infrastructure. The authors describe its features, including MAC layer measurements, traffic differentiation, and admission control. The modules required by the network elements as well as their integration are also presented. Additionally, the paper presents results which validate its correct operation and prove its superiority over plain IEEE 802.11. The authors are convinced that the proposed solution will provide QoS support for a variety of services in future mobile ad hoc networks

The analysis of oak pollen count in selected Polish cities in 2014

Praca przedstawia przebieg sezonu pylenia dębu w wybranych punktach pomiarowych większych miast Polski w 2014 r. Pomiary wykonywano we Wrocławiu, w Sosnowcu, Krakowie, Lublinie, Szczecinie, Bydgoszczy, Drawsku Pomorskim, Olsztynie, Warszawie, Piotrkowie Trybunalskim i Zielonej Górze. Badania prowadzono metodą objętościową przy użyciu aparatów firmy Burkard i Lanzoni. Sezon pyłkowy wyznaczono jako okres, w którym w powietrzu występuje 95% rocznej sumy ziaren pyłku dębu. Pylenie dębu w 2014 r. rozpoczęło się z dużym przyśpieszeniem w stosunku do 2013 r. Najwcześniej pyłek dębu zarejestrowano w Szczecinie, bo już 3 kwietnia. Najpóźniej pyłek tego taksonu pojawił się w Lublinie, dopiero 24 kwietnia. Najwyższe średniodobowe stężenie pyłku dębu – 380 z/m3 powietrza – odnotowano 14 kwietnia we Wrocławiu.This paper presents the course of oak pollination season in selected cities of Poland in 2014. The measurements were performed in Wroclaw, Sosnowiec, Cracow, Lublin, Szczecin, Bydgoszcz, Drawsko Pomorskie, Olsztyn, Warsaw, Piotrkow Trybunalski and Zielona Gora. Volumetric method with the use of Volumetric Spore Trap (Burkard, Lanzoni) was implemented. Pollen season was defined as the period in which 95% of the annual total catch occurred. Pollen season of oak in 2014 started faster in comparison to 2013. The season started first in Szczecin (3 April). The highest 24-hour average pollen count was recorded in Wroclaw on 14 April (380 oak pollen grains/m3)