Exact information ratios for secret sharing on small graphs with girth at least 5

In a secret-sharing scheme, a piece of information – the secret – is distributed among a finite set of participants in such a way that only some predefined coalitions can recover it. The efficiency of the scheme is measured by the amount of information the most heavily loaded participant must remember. This amount is called information ratio, and one of the most interesting problems of this topic is to calculate the exact information ratio of given structures. In this paper, the information ratios of all but one graph-based schemes on 8 or 9 vertices with a girth at least 5 and all graph-based schemes on 10 vertices and 10 edges with a girth at least 5 are determined using two polyhedral combinatoric tools: the entropy method and covering with stars. Beyond the investigation of new graphs, the paper contains a few improvements and corrections of recent results on graphs with 9 vertices. Furthermore, we determine the exact information ratio of a large class of generalized sunlet graphs consisting of some pendant paths attached to a cycle of length at least 5

Lamred : location-aware and privacy preserving multi-layer resource discovery for IoT

The resources in the Internet of Things (IoT) network are distributed among different parts of the network. Considering huge number of IoT resources, the task of discovering them is challenging. While registering them in a centralized server such as a cloud data center is one possible solution, but due to billions of IoT resources and their limited computation power, the centralized approach leads to some efficiency and security issues. In this paper we proposed a location aware and decentralized multi layer model of resource discovery (LaMRD) in IoT. It allows a resource to be registered publicly or privately, and to be discovered in a decentralized scheme in the IoT network. LaMRD is based on structured peer-to-peer (p2p) scheme and follows the general system trend of fog computing. Our proposed model utilizes Distributed Hash Table (DHT) technology to create a p2p scheme of communication among fog nodes. The resources are registered in LaMRD based on their locations which results in a low added overhead in the registration and discovery processes. LaMRD generates a single overlay and it can be generated without specific organizing entity or location based devices. LaMRD guarantees some important security properties and it showed a lower latency comparing to the cloud based and decentralized resource discovery

On a secure distributed data sharing system and its implementation

In this paper we propose a decentralized privacy-preserving system which is able to share sensible data in an encrypted way, that only predefined subsets of authorized entities can recover the data after getting an additional alarm message. In the paper we give a short description of the necessary cryptographic building blocks and the communication protocol. Furthermore, we present the main communication channels and the implementation of the proposed data sharing system. The proposed system achieves the desired functionalities by using secret sharing and two communication networks: an ordinary P2P network where the encrypted information is stored, and a smaller private P2P network called friend-to-friend network, which consists of the authorized parties and handles messages that are necessary to the decryption. The main part of the paper concentrates on the implementation of the system. Keywords: private P2P network, secret sharing, symmetric cryptograph

A poli (ADP-ribóz) polimeráz enzim szerepe diabeteszes komplikációk patogenezisében = Poly (ADP-ribose) polymerase and diabetic complications

A jelen munkában a PARP fehérje szerepét vizsgáltuk a cukobetegség szövődményeinek kialakulásában. Kimutattuk, hogy az erek és a vese károsodásában fontos szerepe van ennek a fehérjének, és a fehérje aktivitásának gátlása állatokban javítja a betegség lefolyását. Összefüggést találtunk a PARP aktivációja, valamint a rosszul beállított cukorbetegség között, és kimutattuk különféle sejten belüli szignál transzdukciós út szerepét ezekben a folyamatokban. A munka számos nemzetközi szintű közleményt eredményezett. | In the present project, we have investigated the role of the PARP enzyme in the pathogenesis of diabetic complications. We have demonstrated that the vascular and renal damage associated with diabetes is importantly mediated by the activation of the PARP enzyme. We have demonstrated a relationship between poorly controlled diabetes and the activation of PARP and we have demonstrated the role of several intracellular signal transduction pathways in the process. The work has resulted in a number of internationally significant publications

Attikai szónokok, papírusztöredékek kutatása illetve feldolgozása = Research on attic orators and papyrus-fragments

A kutatás a kutatási tervben megfogalmazottaknak megfelelően öt kiemelt területen folyt. 1. Hypereidés-szövegkiadás előkészítése (Horváth László): elkészült két beszéd kritikai kiadása és több résztanulmány. Az Archimédés palimpsestus új Hypereidés-szövegeinek (a teljes corpus egyötöde - melynek feldolgozásához Mészáros Tamás is hozzájárult) megfejtésében és értelmezésében elért eredmények miatt a témavezető felkérést kapott a Walter de Gruyter kiadótól, hogy Hypereidés összes műveit a Bibliotheca Teubneriana sorozatban jelentesse meg. 2. A Rhamnus démosbeli Antiphón beszédeinek filológiai magyarázata (Mészáros Tamás): több fontos előadás és résztanulmány született. 3. Janus Pannonius Vocabulariumának, az ÖNB Suppl. Gr. 45 kódexnek feldolgozása (Horváth László és Mészáros Tamás irányításával): Ötvös Zsuzsa elkészült a szójegyzék átírásával, több tanulmány született, melyek a további filológiai kutatás kiindulópontját jelentik. Az ÖAW támogatásával a kódex kiadása belátható távlatba került. 4. Papirusztöredékek az ÖNB Papyrussamlungjában (Láda Csaba irányításával és Horváth László közreműködésével): az Eötvös Collegium fiatal kutatóinak (hallgatók) csoportja négy eddig kiadatlan papiruszt publikál 2009-ben. 5. Nemzetközi szónoklattani konferencia 2007-ben (Horváth László): 2007. szeptember 18-22 között zajlott le az Archimedes Palimpsest Colloquium az Eötvös Collegiumban, melyen több mint harminc külföldi résztvevő közreműködésével konferencia és tudományos műhelymunka folyt. | The research has been carried out in five particular areas. 1. Preparing the edition of Hyperides-text (L. H.): the critical edition of the two speeches have been completed and several papers on related questions have been published. Due to his achievements in deciphering and interpreting the new Hyperides texts in the Archimedes Palimpsest (one fifth of the whole corpus to the procession of which T. M. has also made contribution), the supervisor has been invited by the publishing house Walter de Gruyter to publish the complete works of Hyperides in the series Bibliotheca Teubneriana. 2. Philological interpretation of the speeches by Antiphon (T. M.): several important presentations and papers have been completed on the topic. 3. Processing ÖNB Suppl. Gr. 45 (with the supervision of L. H./T. M.): Zsuzsanna Ötvös has transcribed the vocabulary list and published several papers which serve as a starting point for further philological investigations. With the support of the ÖAW the publication of the codex has become realisable within reasonable time. 4. Fgragments of papyri in the ÖNB (with the supervision of Cs. L. / L. H.): a group of young researchers at the Eötvös Collegium will publish four inedited papyri in 2009. 5. International conference on rhetorics in 2007 (L. H.): in September 2007 The Archimedes Collegium was held in the Eötvös Collegium, where conference and scholarly workshops were organized with the contribution of more than thirty participants from abroad