Our publications

Polyanski P., Bogatyryova H. EDW - edge diffraction wave, edge dislocation wave, or whether tertio est datur? (On the bicentenary of the Thomas Young's wave diffraction theory)

Saturday, 23 July 2011 20:40 administrator
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A dramatic bicentenary history of the Thomas Young's wave interpretation of diffraction phenomena is briefly outlined. Both theoretical and experimental milestones substantiating the Young's diffraction paradigm are discussed. Vitality and topicality of the Young's views on the nature of diffraction are argued. Relation of the Young's concept of diffraction phenomena with the novel decomposition of the solution of the diffraction problem in the spirit of 'singular optics' is considered.
Keywords: diffraction, holography, optical phase conjugation, edge diffraction wave, edge dislocation wave, singular optics,
polarization, quasi-optics

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Porev V., BorovitskyV., Popov S. Increased temperature accuracy of the cathode ray tube camera based on digital signal processing

Wednesday, 03 August 2011 19:30 administrator
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The cathode ray tube cameras can be used for measurement and visualization of 300 - 2000 degrees Celsius temperature fields that apply in an opto-, micro-, and quantum electronics production. The computer simulation of physical processes in the camera allows us to get necessary information for increasing the temperature accuracy by a digital compensation of the errors. The sequence of the computer simulation and the practical results of temperature measurement are represented.

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Last Updated on Wednesday, 03 August 2011 19:36
 

Poryev G. Efficiency of the overlay Network clustering based on the locality metric

Thursday, 14 July 2011 18:54 administrator
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The method of estimating the efficiency of the overlay network clustering in the swarms of peer-to-peer networks is proposed. The brief overview of the locality metric as a topological distance substitute is given and using re-gional Internet registries as information sources for constructing the struc-tural model of the network is substantiated.
Key words: Internet, distributed networks, peer-to-peer networks, locality, clustering.

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Last Updated on Thursday, 14 July 2011 19:13
 

Poryev G. Using the Internet registries to construct а structural model for locality estimation in the overlay networks

Thursday, 14 July 2011 00:00 administrator
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The structure of the database files of the regional Internet registries is ana-lyzed. With the help of proposed method for the locality class estimation is calculated the topological affinity for arbitrary address pairs without using any service traffic. The proposed locality class metric can be used as a dis-tance substitute instead of the traditional trace and ping metrics to construct optimal overlay structure of the distributed and peer-to-peer networks.
Key words: Internet, distributed networks, peer-to-peer networks, locality, regional registries.

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Last Updated on Thursday, 14 July 2011 19:14
 

Poryev G., Poryev V. On the application of peer-to-peer network architeсture for global ecological information and monitoring systems

Thursday, 14 July 2011 00:00 administrator
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Today there exist a wide variety of ecological problems and tasks, whose solutions require the distributed system, dedicated to collecting a multitude of data in real-time in geographically spanned area. The typical task of this kind would be monitoring of the atmospheric conditions in urban areas, monitoring the water properties and pollution rates in river basins etc. And the typical solution involve central processing unit (usually, a corporate or institution-based server) with all the communications hardware necessary plus the distributed grid of mostly identical field units, each of which will periodically send its collected data to the central server for processing and storage.

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Last Updated on Thursday, 14 July 2011 19:14
 

Poryev G., Poryev V. The possibility of reported traffic forgery on private bittorrent trackers

Thursday, 14 July 2011 00:00 administrator
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The overview of the development of concept of peer-to-peer networks is given while historical trends of its progress are analyzed. The content’s lifecycle and load-balancing techniques in BitTorrent networks are reviewed. It is shown that the traffic reports on private trackers could easily be forged.

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Last Updated on Thursday, 14 July 2011 19:14
 

Poryev G., Rudyk T., Sulima O. Traffic regulation and reputation handling in the bittorrent peer-to-peer networks

Thursday, 14 July 2011 19:05 administrator
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Various methods for traffic regulation and reputation handling in the distributive and client context of BitTorrent network are analyzed.
The overview of the methods for the calculation of the user reputation in the private trackers and corresponding reputation-based access systems are performed.

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Last Updated on Thursday, 14 July 2011 19:13
 

Poryev G., Schloss H., Oechsle R. CARMA based MST approximation for multicast provision in P2P Networks

Thursday, 14 July 2011 18:59 administrator
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The Minimum Spanning Tree (MST) problem is one of the most popular and important problems in the research area of distributed computing and  networks. Contrary to the theoretical models where we usually have a global knowledge of all nodes and the corresponding distances for MST  construction, in a realistic network (e.g., Internet) a node always has to rely on local knowledge only, that is it neither knows all other nodes nor exact  distances between these nodes. In this paper we propose an approach for MST approximation based on local knowledge of a small subset of existing  nodes by using the CARMA metric as a distance substitute. According to the evaluation results, our approach achieves a good MST approximation with  respect to a communication cost and avoids extraneous communication needed for latency measurements.
Keywords-Minimum Spanning Tree Problem; Application Level Multicast; P2P Networking

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Last Updated on Thursday, 14 July 2011 19:13
 

Protasov A. Application of FEMLAB software for simulation of the thermal method for NDT

Friday, 22 July 2011 17:26 administrator
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The thermal nondestructive testing (TNDT) method is widely used for inspection of industrial parts and components. The method involves heating the object and subsequently measuring the temperature of its surface. This change in temperature provides information about the test object’s structure. The surface temperature changes if the discontinuity exists inside the object.
The laboratory training allows students to understand the fundamental processes, which take place during the TNDT procedure. Students are able to simulate this procedure use FEMLAB software package. This interactive software package is based on application of partial differential equations for simulation of scientific and technical problems related to TNDT. Applied modes of this software allow the development of models with desired properties of a test object and heat flow. FEMLAB package generates the system of partial differential equations, which represent a complete model of TNDT processes. The finite element analysis method is used for solving partial differential equations.

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Protasov A. The professional training features for NDT graduate students

Friday, 22 July 2011 17:31 administrator
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The Non-Destructive Testing (NDT) specialists carry out a quality exam for various kinds of products, conduct inspection of potential accident industrial objects, and provide their safe exploitation. Such branches of industry as aviation, ground transportation, nuclear power stations, and civil engineering can’t even exist without NDT specialists. All people need high quality products, to be protected from terrorism and technogeneous catastrophes. Thus, NDT specialists are desired in any society. Today Ukraine has a lot of objects and constructions which were built many years ago. Such objects as hydroelectric plants, dams, bridges, inflammable stores, and many others need to be inspected for evaluation of their safety. So, the problem of NDT specialist preparation is very important for Ukraine which had Chernobyl catastrophe in the past.

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Last Updated on Friday, 22 July 2011 17:34
 
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