Viability of Numerical Full-Wave Techniques in Telecommunication Channel Modelling

In telecommunication channel modelling the wavelength is small compared to the physical features of interest, therefore deterministic ray tracing techniques provide solutions that are more efficient, faster and still within time constraints than current numerical full-wave techniques. Solving fundamental Maxwell's equations is at the core of computational electrodynamics and best suited for modelling electrical field interactions with physical objects where characteristic dimensions of a computing domain is on the order of a few wavelengths in size. However, extreme communication speeds, wireless access points closer to the user and smaller pico and femto cells will require increased accuracy in predicting and planning wireless signals, testing the accuracy limits of the ray tracing methods. The increased computing capabilities and the demand for better characterization of communication channels that span smaller geographical areas make numerical full-wave techniques attractive alternative even for larger problems. The paper surveys ways of overcoming excessive time requirements of numerical full-wave techniques while providing acceptable channel modelling accuracy for the smallest radio cells and possibly wider. We identify several research paths that could lead to improved channel modelling, including numerical algorithm adaptations for large-scale problems, alternative finite-difference approaches, such as meshless methods, and dedicated parallel hardware, possibly as a realization of a dataflow machine

Value-Based Ideas or Material Interests? An Explanation of Polish Governmental Preference Formation towards Eurozone Accession

Why did Poland not join the Eurozone despite being integrated economically and dependent on investments and trade with existing Eurozone countries? The reluctance of its government seems puzzling taking into consideration Polish economic exposure to Eurozone countries as well as its commitment to switch to the euro stemming from EU treaties. The Polish governmental position on Eurozone accession demonstrates that monetary integration is not only an economic and legal issue, but it also results from political decisions of individual governments. This paper argues that a complementary understanding of the position of the Polish government on Eurozone accession is possible by looking at domestic ideas and interests. For this aim, the societal approach to governmental preference formation is employed. It focuses on the influence of domestic ideas (value-based collective expectations of voters) and interests (cost-benefit calculations of lobby groups) on governmental positions. In applying the societal approach, this paper has two goals: first, to show that the Polish governments’ reluctance to join the Eurozone stems from domestic societal pressures (value-based ideas and material interests) and, second, to specify the conditions for either ideas’ or interests’ individual bearing on the government’s preference

Re-routing Multicast Connections: A Distributed Approach

In virtual-circuit environments that provide a multicast capability, fixed routing algorithms provide solutions that are only efficient initially and for a short time due to dynamic nature of network environments. We propose a re-routing algorithm that continuously rearranges the topology of the initial connection, in response to changes in the destination set and network status. The re-routing algorithm is cost effective and minimally disruptive to the multicast session. It is based on a modified Steiner tree improvement technique, and it has been designed purposely to meet the requirements for distributed implementation in communications networks where only partial information is available to routing nodes

Prerequisites for Statistical Analyses of the Quality of Instrument Flight Procedures

Instrument flight procedures are essential and critical components of the global aviation system. They are designed for all phases of flight, i.e. the standard instrument departures, standard instrument arrivals, instrument approaches and the en-route phase of flight. Instrument flight procedures are designed from various aeronautical data, information, dimensions, etc., which are named instrument flight procedure elements according to this paper. Development of air navigation systems affect design of instrument flight procedures and flexible use of airspace. The design process is carried out within a framework defined by international and national standards, organizational norms and economic aspects. Instrument flight procedure elements are a fundamental part of the process. Deviations of these elements from full compliance with international regulations can significantly and negatively affect air traffic safety. The objective of this paper was to investigate the basic prerequisites for statistical analysis of the design quality of instrument flight procedures, which have not been explored before. Six prerequisites were proposed for acquiring the data and preparing them for further statistical use

MAP Selection Algorithms Based on Future Movement Prediction Capability in Synthetic and Realistic Environment

Efficient mobility management involves micromobility principles. The performance of the Hierarchical Mobile IPv6 (HMIPv6) protocol, a representative micro-mobility approach, is affected by the Mobility Anchor Point (MAP) selection. In this paper, we propose a new selection method based on a prediction of the future movements of Mobile Nodes (MNs). The proposed algorithms exploit the information about the future availability of MAPs and choose those MAPs that assure a better service. An improvement to the evaluation methodology is also proposed. The algorithms are compared to each other not only in synthetic but also in realistic internet topologies, which has not been a practice in the past. The simulation results show promising improvements in terms of distance from chosen MAPs and frequency of MAP changes. Moreover, we showed that, for perceivable improvement of MAP selection, absolute accuracy of movement prediction is not required. As pioneers in the mobility management analysis in realistic environment, we ascertain that offering MAP services over more than one Autonomous System (AS) proves beneficial

Evaluation and prognostication of financial safety of the business-system is a necessary service of auditing firms

Особливістю управління фінансовою безпекою є те, що в кризових умовах ухвалення управлінських рішень часто здійснюється в обстановці зниження загального рівня керованості бізнес-системою. Сучасні умови зовнішнього середовища змушують вітчизняні бізнес-системи обирати такі інструменти антикризового управління, які дозволять легше адаптуватися до змін умов господарювання. Саме тому виникає необхідність пошуку нових підходів до формування механізму оцінювання та прогнозування фінансової безпеки бізнес-системи з метою вироблення оптимальних управлінських рішень. Враховуючи досвід аудиторських фірм у наданні консалтингових послуг і тенденції розвитку аудиторської діяльності (розширення сфери аудиторських послуг), оправданим буде залучення аудиторських фірм до оцінювання і прогнозування фінансової безпеки бізнес-сиcтем.Financial safety of the business-system changes during a life cycle, adapting itself to the aims and necessities of organization and creating necessary terms for its subsequent growth. Depending on the stage of life cycle of the business-system internal and external threats for its financial safety are changing. An adequate estimation of financial strength of the business-system security at every taken stage of life cycle is important, taking into account the specific of inherent to this stage factors which influence it as well as possibility to forecast their influence at the next stage to neutralize the action of negative ones. The specific feature of financial safety management consists in administrative decisions being carried out in the decline situation of general level of the business-system dirigibility in the crisis coditions. Modern terms of external environment force the domestic business-systems to elect such instruments of anti-crisis management, which will allow more easily to adapt itself to the changes of economic conditions. For this reason there is a necessity to search new approaches for forming of of financial safety evaluation and prognostication mechanism of the business-system to take optimum administrative decisions. During the evaluation and prognostication process of financial strength of the business-system security the influence of subjective factor increases and professional requirements rise for those who conduct such researches. Taking into account the experience of auditing firms in providing consulting services and progress of public accountant activities (expansion in the sphere of public accountant services) the tendency of bringing in of auditing firms to the evaluation and prognostication of financial safety business-system will be effective