Motivated by applications in multimedia streaming and in energy systems, we study duality relations in fi nite queues. Dual of a queue is de fined to be a queue in which the arrival and service processes are interchanged. In other words, dual of the G1/G2/1/K queue is the G2/G1/1/K queue, a queue in which the inter-arrival times have the same distribution as the service times of the primal queue and vice versa. Similarly, dual of a fluid flow queue with cumulative input C(t) and available processing S(t) is a fluid queue with cumulative input S(t) and available processing C(t). We are primarily interested in finding relations between the overflow and underflow of the primal and dual queues. Then, using existing results in the literature regarding the probability of loss and the stationary probability of queue being full, we can obtain estimates on the probability of starvation and the probability of the queue being empty. The probability of starvation corresponds to the probability that a queue becomes empty, i.e., the end of a busy period. We study the relations between arrival and departure Palm distributions and their relations to stationary distributions. We consider both the case of point process inputs as well as fluid inputs. We obtain inequalities between the probability of the queue being empty and the probability of the queue being full for both the time stationary and Palm distributions by interchanging arrival and service processes. In the fluid queue case, we show that there is an equality between arrival and departure distributions that leads to an equality between the probability of starvation in the primal queue and the probability of overflow in the dual queue. The techniques are based on monotonicity arguments and coupling. The usefulness of the bounds is illustrated via numerical results.

The aim of this diploma thesis “Optimalization of organization structure” is the analysis of the current organization form of the company Bosch Rexroth, s r.o. focused on conformity with the organisation processes and the strategic plans and to propose the new optimal organisation. based on the literary analysis of conventions for creating of optimal organisation structures.

This diploma thesis deals with the problematics of revolutions. Namely with various interpretations of Velvet revolution in Czechoslovakia. First part tries to outline historical development of theories of revolution. The Research of revolutions undergone several generations and shifts of interests. This work tries to map the evolution from the oldest modern authors to the current ones and describe their points of view and how they approach revolutions. In second part, there are presented various views on Velvet revolution in Czechoslovakia. First, they are presented schematically and put in context, then they are described in detail. These interpretations are based on various assumptions and see Velvet revolution from various angles. In Third part the various interpretations are juxtaposed and are described, respectively their view of three aspects of Velvet revolution - causes, process and outcomes of revolution. These various views are then commented by using authors of general theories of revolutions. The goal of this approach is to enable better understanding of Velvet revolution, by sharpening the contures of the whole proces and also show the possibilities of use of general theories of revolution. Key words: revolution, theory of revolution, Velvet revolution, causes, process, outcomes

Anaerobinis dumblo stabilizavimas taikomas siekiant sumažinti organinių medžiagų kiekį esantį dumble. Šiame darbe nagrinėjami perteklinio veikliojo dumblo parametrų kitimai, keičiantis apkrovai stabilizavimo metu. Atlikta duomenų analizė. Eksperimentų pagalba nustatyta peleningumo priklausomybė nuo reaktoriaus tūrinės apkrovos. (Vilniaus miesto nuotekų valymo įrenginiuose susidarančiam pertekliniam veikliajam dumblui jį stabilizuojant). Taip pat darbe apžvelgti pagrindiniai veiksniai, įtakojantys veikliojo dumblo stabilizavimą. Atlikti šie bandymai: nustatyta dumblo koncentracija, dumblo peleningumas, pH, lakiosios riebiosios rūgštys, šarmingumas, biodujų kiekis. Pagal turimus duomenys nustatytos peleningumo, pH, šarmingumo, dujų kiekio priklausomybės nuo tūrinės anaerobinio reaktoriaus apkrovos. Darbe pateikiami bandymų metu atlikti tyrimų rezultatai, kurie buvo analitiškai ir dalinai statistiškai apdoroti. Darbo pabaigoje pateikiamos išvados. Darbą sudaro šios dalys: įvadas, trys skyriai, išvados, literatūros sąrašas, priedai. / Reducing organic material amount in sludge an anaerobic excess sludge is applied. In this work was considerated variation of excess active sludge parameter alternating of organic matter during anaerobical digestion. Analysis of data were done. With the help of experiments was ascertained correlation between volatile solids and loading of reactor. (excess active sludge in Vilnius city wastewater treatment plant was stabilized). Was looked through main subjects that have influence for stabilization of excess sludge. Such experiments were done: concentration of sludge, volatile solids, pH, volatile fatty acids, alkalinity, biogas amount. Using existing data correlation between volatile solids, pH, alkalinity, biogas amount and anaerobic reactor loading were found. In the work are represented facts obtained in experimentations. Facts were analyzed and statistically treated. In the end of work conclusions are presented.

No description available.