Кінетичні закономірності селективної флокуляції тонкодисперсних матеріалів

Виконано узагальнення і аналіз кінетичних закономірностей селективної флокуляції тонкодисперсних матеріалів гідрофобними органічними реагентами . Встановлено, що за-лежність крупності флокул від тривалості перемішування пульпи носить нелінійний характер і являє собою двоступінчасту криву. Вторинне укрупнення матеріалу можна розгляда-ти з позицій фізико-хімічної гідродинаміки, як перехід від дифузійного до переважно інерційного механізму зустрічей частинок контактуючих фаз. Регресійна модель, що описує двоступінчасті кінетичні криві флокулоутворення має сігмоїдальний характер.Выполнено обобщение и анализ кинетических закономерностей селективной флокуля-ции тонкодисперсных материалов гидрофобными органическими реагентами. Установлено, что зависимость крупности флокул от продолжительности перемешивания пульпы носит нелинейный характер и представляет собой двухступенчатую кривую. Вторичное укрупнение материала можно рассматривать с позиций физико-химической гидродинамики, как переход от диффузионного к преимущественно инерционному механизму встреч частиц контактирующих фаз. Регрессионная модель, описывающая двухступенчатые кинетические кривые флокулообразования имеет сигмоидальный характер.Generalization and analysis of the kinetics of selective flocculation of fine material hydrophobic organic reagents. The dependence of particle size on the duration of flocculation mixing pulp is non-linear and is a two-stage curve. Re-integration of the material can be viewed from the standpoint of physicochemical hydrodynamics, as a transition from a predominantly diffusive inertial mechanism meetings particles contacting phases. The regression model describing the two-step kinetic curves of floc formation sigmoidal character

Network slicing with flexible mobility and QoS/QoE support for 5G networks

Proceeding of: 2017 IEEE International Conference on Communications. Workshops (ICC Workshops)Network slicing is an emerging area of research, featuring a logical arrangement of resources to operate as individual networks, thus allowing for massively customizable service and tenant requirements. The focus of this paper is to present the design of a flexible 5G architecture for network slicing, building on SDN and NFV technologies as enablers. More specifically, we place the emphasis on techniques that provide efficient utilization of substrate resources for network slicing, ultimately optimizing network performance. The key areas of consideration in our architecture revolve around flexible service-tailored mobility, service-aware QoS/QoE control as well as network-wide orchestrationThis research work has been performed in the framework of H2020-ICT-2014-2 project 5G NORMA

A flexible network architecture for 5G systems

In this paper, we define a flexible, adaptable, and programmable architecture for 5G mobile networks, taking into consideration the requirements, KPIs, and the current gaps in the literature, based on three design fundamentals: (i) split of user and control plane, (ii) service-based architecture within the core network (in line with recent industry and standard consensus), and (iii) fully flexible support of E2E slicing via per-domain and cross-domain optimisation, devising inter-slice control and management functions, and refining the behavioural models via experiment-driven optimisation. The proposed architecture model further facilitates the realisation of slices providing specific functionality, such as network resilience, security functions, and network elasticity. The proposed architecture consists of four different layers identified as network layer, controller layer, management and orchestration layer, and service layer. A key contribution of this paper is the definition of the role of each layer, the relationship between layers, and the identification of the required internal modules within each of the layers. In particular, the proposed architecture extends the reference architectures proposed in the Standards Developing Organisations like 3GPP and ETSI, by building on these while addressing several gaps identified within the corresponding baseline models. We additionally present findings, the design guidelines, and evaluation studies on a selected set of key concepts identified to enable flexible cloudification of the protocol stack, adaptive network slicing, and inter-slice control and management.This work has been performed in the framework of the H2020 project 5G-MoNArch co-funded by the E

Control and management plane helper functions for information centric networks

The rapid evolution of the Internet over past decades has enabled the global communication which has fundamentally changed our lives. As an outcome, millions of users are constantly exchanging an enormous amount of information. Such a massive distribution of information and fast increase of traffic loads have posed a considerable challenge to the functionality of the current Internet. Furthermore, apart from increased communication demands and higher loads of exchanged data, the users’ interests have significantly changed. Users primarily focus on finding or sharing specific information, regardless of the particular end host providing it. Thus, the current network architecture appears to be suboptimal, and perhaps even inflexible to follow the changes in communication patterns. In order to support the emerging user requirements, different overlay data delivery structures have been proposed and implemented. Despite the perceived simplicity of such overlay approaches there are many issues, e.g., efficient resource allocation, which are considered to be suboptimal and not desirable as an architectural solution for information exchange over the Internet. Thus, it is believed that apart from overlay techniques additional powerful mechanisms are still necessary for exploiting the network resources effectively. This thesis identifies information-centric communication as a new concept for efficient exploitation of network resources, solving the current Internet problems, and satisfying the emerging user demands. We carefully study the potential of information-centric communication based on the numerous scenarios found in the literature and adopt the most promising solutions as the framework for building our work upon. In this thesis we focus on developing the mechanism for native support of information-centric communication at all networking layers. Having flexibility as one of the most important requirements, we aim at building a set of information-centric helper functions, each being responsible for a small portion of network functionality. A joint operation of such helper functions leads to significant improvement of network performance without increasing the complexity of network operation. We design, implement and carefully evaluate a variety of helper functions entirely relying on information-centric concepts, carrying out the experiments through both extensive simulations and real testbed environments. We particularly focus on helper functions for the control and management plane. We design and build the modules responsible for topology discovery and creation, topology maintenance and mobility management, extending our helper functionality set with different ancillary mechanisms for optimization of data transfer, such as network coding. We demonstrate the advantage of our approach with respect to simplicity and flexibility of the implementation, as well as the achieved resource utilization and network performance improvements. Particular attention has been paid to the extensibility and optimization of the proposed system of helper functions. Furthermore, its native integration with the fine-grained lower level network operations has been investigated. Finally, we highlight the main remaining challenges of our approach, such as deeper examination of scalability issues and the potential of wide-scale deployment

Performance Evaluation of Network Coding: Effects of Topology and Network Traffic for Linear and XOR Coding

Abstract — In this work we analyze performance of network coding focusing on two specific network coding schemes: XOR and random linear network coding. We have simulated different topologies and traffic patterns in order to provide better understanding of network coding behavior and its possible bottlenecks. As a part of our performance evaluation we consider also computational complexity of coding and decoding operations which influence packet latency. In particular, we indicate potential drawbacks and trade-offs of network coding when applied on specific topologies under specific circumstances by monitoring the differences in XOR and random linear network coding approaches. Finally, we apply network coding on the topology of existing research network Abilene [1] in order to evaluate network coding performance under realistic conditions. I