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Packet scheduling is one of the key mechanisms that will be used in network elements (switches and routers) for supporting real-time applications in broadband networks. Provision of Quality-of-Service (QoS) guarantees is an important and challenging issue in the design of integrated service packet networks. Scheduling disciplines are an integral part of the problem and are closely related to other aspects of network modeling such as traffic charaterization and QoS specification. In this paper we discuss two priority scheduling mechanisms: Head of Line (HoL) and preemptive discipline; for both, we propose an analytical description and present numerical results obtained by Markov chain. A novel mechanism called Dynamic-Weighted Fair Queuing (Dynamic-WFQ) which depends on the Classes of Service and the queue occupancies is proposed. An example of selection function is solved by Markov Chain and the results are validated by simulation. Finally, we compare the performance evaluation of multimedia communication scheduling algorithms described above.

International regulations require aircraft to be separated in approach phase of flight by up to six nautical miles (11.12 km) due to the potential hazard caused by the swirling air left in their wakes. This 'wake vortex' is now the subject of intense worldwide research to understand the nature of the phenomenon and find ways of making air travel safer while reducing congestion around airports. "With the world airline fleet expected to double in size over the next 15 years and the giant A380 entering service in 2005, solutions to the wake-vortex problem cannot come too soon for the aerospace industry and therefore there is a strong need for developing a dynamic air traffic control wake vortex safety and capacity system." [1] This paper describes the concept of integrated transportation system regarding the current state-of-the-art technologies.

Transportation, Info-Communication and Postal Services (TICPS) have a special position in the sector of services when taking into consideration the organization and management of processes. The paper describes the common features of services from the quality management point of view and compares the common used criteria in selected types of services. In the paper, the basic approaches to quality measurement in TICPS from customer and organisational points of view are presented as well. The paper is based on the solution and the conclusions of research project 519/2 "The model of a communication service within a territory administration - region".

The pavement as unit is able to perform services, provided that we ensure good synergy of layers and especially good adhesion between used materials. Adhesion knowledge allows to design suitable technology by preventing defects and to ensure service ability and life of pavement.In the paper there is a theoretical analysis of problem of bitumen binders adhesion to aggregate, basic methodologies to evaluate this property and specific results achieved at measuring by the method STN 65 7089 and EN 12272-3. At the same time the results are compared from the type of aggregate point of view as one of the most important factors that influenced adhesion.

The paper discusses possibilities of a description of material fatigue and prediction of service life of machine parts on the basis of stress state calculations using the finite element method (FEM). It focuses on the local approach to the assessment of service life that is based on the determination of elastic stress peaks in stress raisers (notches) and on the derivation of the fatigue stress curves for assessed structural points. The method of taking into account the stress concentration and stress gradient during the determination of synthetic fatigue curves is described. Furthermore, methods of processing the loading history and correcting mean stress values of loading cycles are described.

Traffic density and climate are important external factors influencing pavement mechanics. Climatic conditions influence the service life of materials, damage to roads etc. In many countries the climatic characteristics are implemented into calculation systems for pavement construction. The importance of the implementation of climate characteristics into the calculation systems is increasing in the context of global climatic processes and changes, especially the changes in air temperature. The aim of the following paper is to highlight the changes of climatic characteristics used in highway engineering and their effect on the change of pavement thermal flow.

The paper deals with the public transportation system in Zilina. The research study initiated by the Transportation Company of Zilina has been performed with the aim to solve the problems concerning public transportation service in the urban area. The main goal of the research study was to evaluate how well the bus stops serve the public and to identify the segments of the traffic routes, which are risky for buses and trolleybuses operation. Geographic information system was applied to solve these problems by analysing the geospatial data referring to the transportation system. The paper includes the outputs from these analyses.

This paper proposes a new Admission Control strategy with Quality of Service (QoS) preservation for GSM networks. System initiated handover calls are used in the central cell in order to decentralize the traffic and redistribute it throughout the whole cluster. Although the channels and the cell size are fixed, the system behaves as if it had the 3G feature called soft capacity. The mobility characteristics of the users are investigated. Low speed and high speed moving users are used as input in the system and the effect of mobility on the proposed algorithm is extracted. Simulation results show that the proposed Admission Strategy is flexible, efficient and very useful in situations when the traffic is centralized.

Man has always lived in two spaces, natural environment and civilizational space. Civilizational space has been formed by man, is built up of all human activities, and has been created among others as human response to hazards. Variability of civilizational space causes the necessity of keeping up with changes. Things that were good yesterday today are of no value, which means they no longer protect from unwilling events. Description delay in relation to its constant change in civilizational space along with its complexity causes difference in interpretation. Occurrence of unwilling event is a sign that the accepted solution was bad and needs improvement. Thus, civilizational space is a source of hazards.

It is considered that providing safety in universal dimension is exclusively responsibility of a public authority and the authority is fully responsible for efficient implementation of systems concerned with it. In reality, there is no prospect of not having incidents and therefore, there is no absolute safety. If such ideas exist anywhere, they are only theoretical concepts. Safety is a condition of the surroundings and natural environment of a local community. The condition level is defined by the degree of existing risk in that community. The risk is ubiquitous and inevitable as it exists in nature and civilian space. So the local governing body must decide what level of risk it is able to accept.Safety includes a wide range of undertakings be realized in order to provide security in all areas of concern in the state. Therefore, safety is the result of activities of different institutions, services, organizations, and also individual human being, its closest surroundings, local and central authorities.

When speaking about psychology of rescue actions there should be no restrictions to the incident only but the problem should be studied within the whole time, i.e. before, during and after the event. Disaster is irreversibly connected with a tragedy that falls deeply into social memory. Frequently it changes irrevocably the way of living of individual people and whole local population. Nonetheless, as time passes emotions connected with the disaster decrease. And even though that for various individual people the passage of time may not be of such profound importance, in the case of local population indifference grows to possible future incidents of this sort. Thus we are faced with a situation in which greatly faded emotions connected with "past" history coexist with the hope that the same thing would not take place in future. In the article this period of time is defined as a period "after-before" the disaster and is related to the period of drama and the period of discomfort.

Qualitative norms at present being introduced into all sectors of management also enter successfully new sorts of managerial activities including safety management. Contractual safety interest of personal, material and non-material protected assets by means of a model process orientated protection meets fully requirements of continual improvements of managerial quality system of protection process.The aim of the article is to arrange logically the phases of the safety process development by means of accentuating existence of the private security service law, categorisation of individual parts of the hierarchy of the development of security services and subsequent detection and pre-estimating risks in the framework of the safety system as a basic element of the safety conception.

The examination of the possibility of the nation-wide delivery of postal packets no larger than 10 kg. The comparison of the present and expected packet service level. The presentation of the new packet forwarding service and the conditions for its introduction. The putting into figures of the extra turnover at the distribution points and of the transportation tasks in the new packet delivery system. Cost calculation for the service according to the EU regulations.

A Bandwidth Broker (BB) is an automated resource manager in the Differentiated Services architecture. It manages Quality of Service resource allocation requests within a single or successive DiffServ domains based on the available resources and on the Service Level Agreements formerly negotiated between the customer and its service provider. If used for multi-domain resource management, BBs negotiate among each other on behalf of the service initiator. Additionally, BBs also participate in transit domain communication by coordinating SLAs across domain boundaries. Various BB architectures have been proposed in the recent years, some of them even have been implemented, but all of them are in a preliminary stage or do not address important issues such as bi-directional resource allocation. In this paper we propose a BB architecture that includes policy manager functions for authorization, supports quantitative and qualitative services, handles bi-directional resource allocation and features a vendor-independent resource allocation approach, i.e., neither software nor hardware modification of core routers are required.

This paper considers the role that universities can play in supporting lifelong learning by the adaptation of teaching methods to provide in-company education directed at specific roles and tasks. It considers the ways work-based learning (WBL) as a teaching methodology can inject new theories, concepts and models directly into industry. It balances the positive benefits of WBL with a critical appraisal of its drawbacks, particularly with respect to the threat of relaxation of academic standards and the dangers of gradual infection of academic integrity across all delivery methods. It looks at the opportunities for WBL in the Slovak Republic and concludes that on balance the new teaching technology is sound, but it urges caution in the approach to WBL and for the establishment of systems to ensure academic standards are maintained.

The electric equipment of traction vehicles has undergone very fast development during the last period. Traction drive was changed dramatically where induction motors took over. Control of induction motors needs sophisticated control circuitry for control of static converters, which produce three-phase current of variable frequency and variable voltage. Performance of the drives and vehicles are then determined by the control techniques, which enable complete automation ofthe train motion, as it is demanded mainly for high-speed service.

The future integrated service networks supporting multiple traffic classes will require customized admission control and bandwidth sharing strategies, which meet the diverse needs of QoS (Quality of Service)-assured (stream) and best-effort (elastic) services. Recent research results indicate that it is meaningful to exercise call admission control (CAC) even for elastic (best-effort) traffic, because CAC algorithms provide a means to prevent e.g. TCP sessions from excessive throughput degradations [1], [2]. Based on a model of a single link introduced in [2], we evaluate different pricing strategies assigned to elastic calls by determining an optimal CAC using Markov Decision theory. We will show that optimizing CAC not only maximizes average revenue, but also improves blocking probability of high priority stream traffic and QoS of elastic traffic as long as appropriate pricing functions are applicable.

Communication networks play an important infrastructural role in the crisis management. To fulfill this role, they have to be robust enough. The robustness is an aspect, which will have to be taken into account also in NGNs (Next Generation Networks). The paper introduces a reference model of the architecture and protocols for robust NGNs. Based on characteristics and requirements for the control architecture, it shows how the control layer can be decomposed, it identifies the basic network elements and the interfaces and protocols that might be used for their interworking. Based on the characteristics and requirements of transport and connectivity layers architecture, and using the examples of different network types and technologies, the authors try to identify the general functions of the transport and connectivity layers in the network.

Development in almost all sectors of economy will immediately affect the transport sector. We can say that growth in economy leads automatically to growth in road transport. As a continuous process the road transport industry produces vehicles by new technologies and transport operators finance this section by purchasing new trucks and coaches. There is a continual and tightened process in the road transport legislation, the EU has elaborated conceptions for achieving sustainable development. The state transport policy of the Slovak Republic has to reflect specified results and conceptions, otherwise road transport in the Slovak Republic becomes the brake of sustainable development.

Communication in emergency situations requires not only specific verbal but also non-verbal competencies of persons involved. Verbal communication comprises, apart from speech culture and the way language is used, also language competence which is to be properly applied in discourse. If language competence fails, non-verbal communication (body language) takes place.

Risks of every person's life and property endangerment caused by natural disaster, technological average or social crisis are increasing. It is the reality of life that this danger can arise whenever and wherever, often even in unexpected situations. One of the most important tasks when solving any special situation is salvage of persons, animals and property from endangered buildings or areas. Evacuation provision and its actual realization are inseparable parts of this activity. This article deals with evacuation provision and solves its technical provision with a focus on logistic provision.

Inventory systems play an important role in manufacturing and service providing organisations to support fluency of production or service. Evolution in time and environment of risk usually characterise operation of such systems. Proper control rules are required for decision making on replenishment orders. If stochastic dynamics of system motion exhibits the Markovian property, then Markov decision models can be employed to reveal a cost-effective inventory control policy. A single-item periodic-review inventory system in the maintenance centre of amanufacturing or transportation organisation with aPoisson arrival stream of demand requirements for spare components is introduced in the paper. The corresponding discrete-time Markov decision model with finite state and action spaces is described for sequential decisions on order sizes over an infinite planning horizon. The long-run expected average cost per unit time is the criterion of interest to be minimised by an optimal inventory control policy.

This paper deals with a problem of inhabited region partitioning. The partitioning is performed when a public administration system is changed. Location of subregion centres is usually connected with the partitioning. Both of these activities, the location subregions centres and forming of the subregions, have impacted public service accessibility. When the service provided to inhabitants is concentrated in the subregion centres, accessibility can be evaluated and the problem of optimal partitioning and centre location can be solved. This paper shows various partitioning problems and reports on associated solution techniques and results obtained for real-sized instances.

Research into information and communication technologies tends to be dominated by the perspectives of technological determinism and theories of social shaping. Actor-network theory has emerged as an alternative approach for understanding and interpreting sociotechnical change. It has been applied to a wide variety of technologies and been used to explore how technology both constructs and is constructed by different stakeholder groups and how companies promote their interests through published texts and the courts to "seize control" of technological developments (Bowker, 1992). This article borrows from actor-network theory in order to explore how influential actors in the process of social change attempt to stabilise forces to their own advantage. By way of analogy with the rapid development of a global communication infrastructure for cable, telephone, PC, TV services etc., the article focuses on the most significant development in the communication infrastructure during the nineteenth century - railways, and in particular on the role of this technology in the opening up of the American West.

Two international corridors "Va" and "VI" pass through Žilina region, but yet the road network density of the region belongs to the lowest in Slovakia. The road network is loaded excessively and main arteries come under a section with a maximum accident rate. The model of the communication attendance of the region that has been solved recently deals with the road network in the region in the terms of the transportation system integration. The paper presents basic characteristics of the network, information on the present state of the traffic, as well as principles of a traffic modelling process. The main resources for improving the traffic situation based on the evaluation of present situation and forecast for network loading are presented in the conclusion.

The scientific paper presents an algorithm and methods of strategic decision making process by top management and ways of eliminating and resolving crisis situations caused by accounting, financial and economic risks. The algorithm deals with a business's lifetime stages and presents the risks, as well as the methods to analyse such risks, based on both external and internal factors of managerial environment. The aim is to define the risks and ways of eliminating them. The paper includes results of the EP 7260 (Brno, 1998-2000), GA MSM 431100007 (Brno 2000-2001)s and EP - 12/2001-2003 (Brno, 2001-2002) research projects. Methodology is based on analytical-synthetic methods, comparison, controlled interview, strategic decision making process, crisis management methods and selected methods of the accounting, financial and economic analysis. The paper also follows up the works published at conferences and in scientific journals FŠI ŽU Žilina (2000), SPU FEM Nitra (2000-2002), PEF ČZU Praha (2000-2001) and IAES (Vienna, 1999), (Montreal, 1999), South Carolina (2000), and Paris(2002). Results of the research have been verified on selected enterprises in the process of dealing with crisis situations which afflicted these enterprises owing to unsuitable reactions to changes in the managerial environment.

The article aims to analyze the concept of crisis planning in civil defense system. Strategic plans are worked out by managers of the highest rank and define general aims of the organization. Elements of risk, threads, and ways of activity in crisis situation should be taken into consideration during strategic planning which is the planning of civil defence. Plans for civil defence are worked out in order to assignate and get ready for organizational and material enterprises of civil defence proper to real possibilities. They are prepared by state administration and local governments, factories and other units and institutions which are responsible for preparing and realization of tasks of civil defence. The main aim for working out the plans for civil defence is to get ready appropriate organizational and material enterprises for civil defence in accordance with foreseen threat and needs and real possibilities of the planning rank. The full scope of civil defence tasks of given rank should be given in plans. Providing civil defence formation with technical and military equipment is realized by civil defence inspectorate. Individual protective means against contamination can be bought in regional warehouse of civil defence equipment, while supplementary means should be done individually.

Paper reports on basic principles in development of integrated transport systems in the region. It explains reasons why integration of mass passenger transport is necessary, as well as procedures of its realization with presentation of economic, legislative and organizational measures.Everything what IDS brings are new, advanced organizational and economic relationships between subjects which participate in mass passenger transport either as passengers, transport operators, or districts, regions, towns, villages or the state.

Current development of material base and technology enables different ways to improve heat-insulating properties of existing packing constructions of the building. Particular ways are different among themselves concerning the service life. This contribution deals with the appreciation of additional thermal insulation while taking into account the return of financial expenses in the relation to its service life. Basic calculation formulas and their graphical illustration (which gauges economical effectiveness) are presented.

The basic idea of the article is to show various problems of control and management in transportation systems and the necessity of an available information support. The importance of transportation and some ideas on its significance for a modern society is reflected in the paper. The model of a transportation system is further described together with some optimisation problems and methods how to solve them. The necessity of a generalisation of a data model and standardisation of data on the transportation infrastructure as well as statistical data on transportation flows is stressed as abasic need for any exact method of control in transportation systems.