30 research outputs found
On Capacity Regions of Discrete Asynchronous Multiple Access Channels
A general formalization is given for asynchronous multiple access channels
which admits different assumptions on delays. This general framework allows the
analysis of so far unexplored models leading to new interesting capacity
regions. In particular, a single letter characterization is given for the
capacity region in case of 3 senders, 2 synchronous with each other and the
third not synchronous with them.Comment: It has been presented in part at ISIT 2011, Saint Petersburg. This
extended version is accepted for publication in Kybernetik
WIRELESS APPLICATION PROTOCOL PERFORMANCE
Our work addresses the various performance testing aspects of the WAP architecture. For a systematic
approach at first the architectural elements have to be identified. Then appropriate testing methods have
to be found for testing each element and for the test of the entire architecture.
In this paper we shall outline a theoretical basis for testing the influence on the performance of the
wireless network and the IP backbone through the service quality parameters. First the service quality
parameters are introduced from the provider and the user viewpoint, then the effect of the network
(wireless and IP backbone) through bearers and transport protocol overheads on these parameters is
analyzed. Conclusions are drawn regarding the results of the analysis and further steps are outlined for
the refinement of our study. The results have not been confirmed by
measurements yet, we are working
on appropriate test scenarios to validate the outcomes and to refine our model.
The final purpose of the work is to specify a performance parameter monitoring system for in-use
WAP architectures that would tune the WAP parameters `on the fly´ in order to
optimise the service quality parameters from the user viewpoint
Egyenlőtlenségek az információelméletben = Inequalities in information theory
A pályázat a klasszikus Ă©s kvantum-informáciĂłelmĂ©let bizonyos tĂ©maköreinek kutatásával foglalkozik. 1. A relative entrĂłpia Ă©s az alfa-relative entrĂłpia szerepe az elĂ©gsĂ©ges statisztikában Ă©s a hipotĂ©zisvizsgálatban, a relative entrĂłpia geometriája Ă©s rá vonatkozĂł egyenlötlensĂ©gek. 2. A csatornák kapacitása, a Holevo-kapacitása kvantum informáciĂłelmĂ©leti csatornáknak, memĂłriával rendelkezĹ‘ csatornák, a tĂpusok mĂłdszerĂ©nek általánosĂtása Ă©s felhasználása bizonyos informáciĂłelmĂ©leti problĂ©mákban, pĂ©ldául ismeretlen csatorna kĂłdolása. 3. Statisztikailag Ă©s informáciĂłelmĂ©leti szempontbĂłl releváns geometriák, a Fisher-informáciĂł. 4. Szoboljev-egyenlĹ‘tlensĂ©gek Ă©s kapcsolatuk a mĂ©rtĂ©k-koncentráciĂłval. Ilyen egyenlĹ‘tlensĂ©gek általánosĂtása az Ăşn. szabad valĂłszĂnĂĽsĂ©gelmĂ©letben. Lipschitz lekĂ©pezĂ©sek alkalmazása normális eloszlásĂş vĂ©letlen vektorokra Ă©s Szoboljev-tĂpusĂş egyenlötlensĂ©gek levezetĂ©se belöle. A kutatás mellett fontos szerepet kap fiatal kutatĂłk nevelĂ©se, rendszeres informáciĂłelmĂ©leti szeminárium Ă©s egy informáciĂłelmĂ©leti iskola szervezese, valamint a pályázat junior rĂ©sztvevĹ‘jĂ©nek PhD disszertáciĂłja. | The project contains the research of certain areas in the classical and quantum information theory. 1. The role of relative entropy and alpha-relative entropy in sufficient statistics and hypothesis testing., the geometry of relative entropy and related inequalities. 2. Capacity of channels, the Holevo capacity of quantum mechanical channels, channels with memory, the generalization of the method of types and its use in certain information theoretical problems, for example the coding of unknown channels. 3. The study of geometries which are relevant from the point view of statistics or information theory, Fisher information. 4. Szobolej inequalities and their relations to concentration of measures. The generalization of Sobolev inequalities to the setting of free probability. Application of Lipschitz mappings to normally distributed random vectors, and the proof of Sobolev-type inequalities. Besides the reserch activity, the education of young reserchers play important role. The team plans to organize a regular reserch seminar on information theory and school for students on information theory. The junior member of the team will prepares his PhD thesis
Az akadálymentesĂtĂ©s Ă©s az akadálymentessĂ©g az utazĂłi lĂ©tezĂ©s dimenziĂłiban – kĂ©t világ paradigmaváltĂł találkozása
Manapság egyre több tanulmány jelenik meg az akadálymentesĂtĂ©s Ă©s a turizmus közötti sokrĂ©tű kapcsolatrĂłl, vagy legalábbis a turizmuskutatĂłk már Ă©rdeklĹ‘dĂ©st mutatnak az akadálymentesĂtĂ©s kĂĽlönbözĹ‘ aspektusainak vizsgálata iránt. Közismert ugyanakkor, hogy a szolgáltatĂłknak e tekintetben mĂ©g mindig van hová fejlĹ‘dniĂĽk. SzomorĂş, hogy az emlĂtett vizsgálatok gyakorlatilag teljesen elhanyagolják mind az akadálymentessĂ©g filozĂłfiai szempontĂş meghatározásá(nak szĂĽksĂ©gessĂ©gĂ©)t, Ăgy nyilvánvalĂłan a gyakorlatban valĂł alkalmazhatĂłságát is, mind az empirikusan igazolhatĂł pozitĂv hatásait, holott ez a jĂł Ă©s önállĂł Ă©lmĂ©nyekben gazdag utazĂłi lĂ©t megvalĂłsulásának elĹ‘feltĂ©tele. Nagyon kevĂ©s szĂł esik az akadálymentessĂ©g Ă©s az akadálymentesĂtĂ©s filozĂłfiai olvasatairĂłl, ami a szerzĹ‘k vĂ©lemĂ©nye szerint a megfelelĹ‘ akadálymentesĂtĂ©s megvalĂłsĂtásának elĹ‘feltĂ©tele
Fundamental Accessibility and Technical Accessibility in Travels—The Encounter of Two Worlds Which Leads to a Paradigm Shift
It is a positive phenomenon that more and more studies are being published on the
diverse relationship between accessibility and tourism nowadays. This indicates that now at
least tourism researchers are showing an interest in the examination of the different aspects of
accessibility. Nevertheless, it is a well-known fact that service providers still do have much room
for development in this respect. It is sad the examinations mentioned practically totally neglect the
definition of accessibility from a philosophical perspective—or its need to be defined, so evidently
its applicability in practice and its empirically justifiable positive impacts are not discussed,
either, though in the authors’ view it is a prerequisite for the realisation of a traveller’s good and
independent experiences. Unfortunately, very little is said in the previously mentioned scrutinies
about the philosophy of accessibility which, in the authors’ opinion, is a prerequisite for the
accomplishment of adequate accessibility. Coming from all these and also on the ground of their
previous researches, and also from the international empirical research conducted in five countries
on the travel habits of people with disabilities by the authors, they are convinced that accessibility
in itself shows, and leads to crisis phenomena, because the spirit of accessibility is simply missing
from both the professional and everyday practical thinking. One explicit manifestation of this is
the fact that travel becomes free from experience as a result of partial accessibility—or it generates
“specific experiences” that can be interpreted as the negative pole of Michalkó’s paradigm of
beatific travel. The conclusion of the paper is that the creation of the paradigm of fundamental
accessibility is a justified must