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Multicast routing in UMTS technology
Kokeš, Roman ; Novotný, Vít (referee) ; Šimek, Milan (advisor)
This Master thesis is about multicast in mobile network 3rd generation UMTS(Universal Mobile Telecommunacitions System). UMTS network primary designs for data transfers and supports new services as real-time transfers of multimedia streams. This is reason why mobile network was equiped also with multicast service. When a lot of users want to receive same data (e.g. tv program) the network excessives load of transmission same data and the server have to keep connection to each user. Group 3GGP developed multicast service for UMTS, which name is MBMS (Multimedia Broadcast and Multicast Service). Thesis analyses function of this service in mobile network. First part describes basic principles of UMTS network and its structure. Next part focuses on change of main node (SGSN and GGSN) and of new node BM-SC(Broadcast-Multicast Service Center). This new node is main node for control of multicast transmission. BM-SC connects to server which provides multicast data for users and provisions individual phase of MBMS session. It was created new procedure which supports multicast session (e.g. Activate MBMS service). Next part focuses on GPRS Tunneling Protocol (GTP). This protocol is used for transfers control and user’s data in tunnels inside core network. This part describes structure of data and control messages. Last part analyzes multimedia transfers in UMTS with program Opnet Modeller.
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Decrease in employment of women taking care of children under three years old as a result of parenthood
Bartůsková, Lucia ; Kotýnková, Magdalena (advisor) ; Krebs, Vojtěch (referee) ; Šimek, Milan (referee)
The dissertation addresses the issue of the relationship of parenthood, employment and economic inactivity of childcare holders. It focuses on the mother's motivation to work (mothers taking care of children under 3 years of age) in the context of Czech social policy measures. The aim of the thesis is establish proposals for measures that would encourage the motivation of women with children up to 3 years to return to work and simultaneously quantify the impact of these measures on the state budget. This dissertation builds up on the underlying studies (Jahoda, Šinkyříková, 2011; Kalíšková, 2012). These studies deal mainly with examining implemented reforms in the view of their support to women's employment and their effects on household incomes. The decision making of mothers about their involvement in the labour market was analyzed by indicator of Effective cost of return to work. Negative net financial effect of returning to work was found independently of the region and the extent of the examined working time of women, taking care of children up to 2 years. For mothers taking care of children from 2 to 3 years old was this negative net financial effect detected only partly. This result clearly demonstrates that mothers, taking care of children below 3 years of age, entering the labour market are confronted with very high additional costs that would not be covered by their income from employment and other received benefits. Estimated amount of potential wages, which would encourage women to return to work, reach in some cases up to four times the median wage of women in the region. Given these findings, this dissertation proposes several specific social policy measures, which would support the mother's incentives to work return. Economic effects of the proposed measures were quantified, including the cancelation of conditional entitlement to parental benefit, introduction of tax relief for working mothers and 50% relief on employer's mandatory contributions, which employ parents part-time. Implementation of these measures, which would motivate more women to return to work, would bring an estimated net income effect for the state budget amounting to 9.5 billion crowns per year.
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Atmosférický DC koronový výboj v N2-NO směsích: energetická účinnost a cena odstranění NO
Pekárek, S. ; Šimek, Milan
This paper focuses on de-NOX efficiency of the DC atmospheric pressure positive corona discharge enhanced by the flow of the mixture of nitrogen with traces of NO. The experimental findings indicate that the transformation of nitric oxide is controlled by the production of atomic nitrogen. For a particular energy density the NO decomposition increases with flow rate and higher NO removal is obtained for lower initial NO concentrations. Production of NO2 increases with increasing NO removal and NO removal energy cost for energy densities exceeding 2 kJ/m3 converges to about 100 eV/molecule. Providing that the removal of NO is predominantly driven by N atoms this would imply that the specific energy cost for the dissociation of N2 is approximately 200 eV/molecule.
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Interakce UV záření s povrchovým nábojem v N2 povrchovém DBD
De Benedictis, S. ; Ambrico, P. F. ; Dilecce, G. ; Šimek, Milan
In this paper we report on space and time resolved spectroscopic measurements on Masuda type surface DBD fed by N2. In our configuration the discharge presents some defects that lead to the formation of some bright spot inside a regular discharge region formed by streamers. We have carried out an optical investigation of both the regular discharge region and the bright spot one with the aim to stress the aspects of photo emission contribution in the dynamics of microdischarge. We have carried out also spectroscopic space and time resolved investigation of discharge emission when UV photons by a pulsed laser interact with the dielectric surface of DBD. There is a similarity between the time evolution of emission from bright spots and that produced by laser photons.
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Intenzita záření a teplota vyhasínajícího stejnosměrného výboje v směsi dusík-kyslík
Krčma, F. ; Mazánková, V. ; Soural, I. ; Šimek, Milan
This contribution focuses on the oxygen influence to the pure nitrogen post-discharge. The DC flowing afterglow in Pyrex tube at discharge current of 150 mA and pressure of 1000 Pa was studied by optical emission spectroscopy at decay times in the range of 3 – 45 ms. Band head intensities of 1st and 2nd positive and 1st negative nitrogen spectral systems were observed as a function of oxygen admixture ( 0-5000 ppm). The nitrogen pink afterglow effect was observed in all cases. Temperature during the afterglow was determined by two different ways. The first one was the direct calculation of the rotational temperature of nitrogen 1st positive 2-0 band using numeric simulation. The second way was the strongly temperature-sensitive ratio of band head intensities originating from 11 and 12 vibrational levels of N2 (B 3g) state because these levels were populated during the afterglow mainly by the atomic nitrogen recombination.
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Optické a elektrické charakteristiky koplanárního povrchového bariérového výboje v dusíku
Šimek, Milan ; Homola, T.
We inspected basic electrical and optical characteristics of dielectric coplanar surface barrier discharge (DCSBD) driven by AC high voltage at atmospheric pressure in high purity nitrogen. Voltage and current traces together with intensity evolution of most important emissions were registered with high time resolution in the UV-vis-NIR spectral range and for various densities of micro-discharges generated on the DCSBD surface. It comes out that most intense emissions are produced by a) energetic electrons through direct electron impact excitation/ionisation of N2 molecule and b) N2(A) metastable species through N2(A)+ N2(A) energy pooling and N2(A)+NO resonant energy transfer processes.
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Účinnost generace ozónu v koplanárním povrchovém bariérovém výboji v syntetickém vzduchu
Šimek, Milan ; Homola, T.
Efficiency of ozone formation by Dielectric Coplanar Surface Barrier Discharge driven in atmospheric-pressure, dry synthetic air was examined in a wide range of applied energy densities (0.01-1 Wh/l). Applied energy density was controlled by combining appropriately dissipated discharge power with airflow rate (5 – 50 l min-1). The O3 concentration was monitored outside the discharge chamber by means of non-dispersive UV photometric O3 analyzer. From the ozone production concentration measurements, we evaluated ozone production and yield. The ozone concentration, production and yield reached 800ppm, 5 g/h and 40 g/kWh, respectively.
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