Networks of queues

1976 ◽  
Vol 8 (2) ◽  
pp. 416-432 ◽  
Author(s):  
F. P. Kelly
Keyword(s):  
Communication Networks ◽  
The State ◽  
Machine Interference ◽  
Equilibrium Distributions ◽  
Reversible Processes ◽  
Networks Of Queues

The behaviour in equilibrium of networks of queues is studied. Equilibrium distributions are obtained and in certain cases it is shown that the state of an individual queue is independent of the state of the rest of the network. The processes considered in this paper are irreversible; however, the method used to establish equilibrium distributions is one which has previously only been used when dealing with reversible processes. Results are obtained for models of communication networks, machine interference and birth-illness-death processes.

Networks of queues

1976 ◽  
Vol 8 (02) ◽  
pp. 416-432 ◽  
Author(s):  
F. P. Kelly
Keyword(s):  
Communication Networks ◽  
The State ◽  
Machine Interference ◽  
Equilibrium Distributions ◽  
Reversible Processes ◽  
Networks Of Queues

The behaviour in equilibrium of networks of queues is studied. Equilibrium distributions are obtained and in certain cases it is shown that the state of an individual queue is independent of the state of the rest of the network. The processes considered in this paper are irreversible; however, the method used to establish equilibrium distributions is one which has previously only been used when dealing with reversible processes. Results are obtained for models of communication networks, machine interference and birth-illness-death processes.

scholarly journals Communication Opportunities of Civil Society Institutions in Countering the Challenges of Post-Pandemic Postmodernity

2021 ◽  
Vol 12 (1Sup1) ◽  
pp. 335-345
Author(s):  
Vasyl Marchuk ◽  
Liudmyla Pavlova ◽  
Hanna Ahafonova ◽  
Sergiy Vonsovych ◽  
Anna Simonian
Keyword(s):  
Civil Society ◽  
Communication Networks ◽  
Local Governments ◽  
Security Policy ◽  
The State ◽  
Modern World ◽  
Free Access ◽  
Democratic Development ◽  
Information And Communication ◽  
Main Thing

The modern world space, which is affected by the post-pandemic consequences, is noted by the globalization of society, the increasing role of citizenship in making important state and international decisions has become possible in the context of the information revolution and has its own characteristics of communication in information and communication networks. The importance and need for a thorough study of the chosen topic is that the widespread use of various forms and methods of civil communication, free access of citizens to information at all stages of decision-making and the functioning of central and local governments, the participation of civil society institutions in the work of expert, consultative, and advisory public councils on the expression and protection of the rights and freedoms of citizens, public control, direct electronic receipt of public services, etc. are important factors in the democratization of government in post-pandemic modern times. After all, we are talking about a deliberate orientation to new values - the person and the collective, their direct participation in the democratic organization of life of the state and society. The main thing in this context is that the rational consensus of civil society and the state is a factor in universal social discourse and a strategic resource for democratic development in the context of post-pandemic modernity. The aim of the article is to consider the epistemological and sociocultural aspects of the functioning of the communication capabilities of civil society institutions in the context of revealing the possibility and significance of their involvement in the processes of implementing state security policy.

Location-Based Services and Navigation in Smart Phones

2012 ◽  
pp. 196-229
Author(s):  
Ling Pei ◽  
Zhengjun Liu
Keyword(s):  
Communication Networks ◽  
Basic Concept ◽  
State Of The Art ◽  
Smart Phone ◽  
The State ◽  
Location Based Services ◽  
Smart Phones ◽  
Technical Solutions ◽  
New Generation

The ubiquitous positioning ability and abundant computation capability of a smart phone allow the provision of a variety of location-based services (LBSs). This chapter focuses on the fundamental elements and principles of LBS in a smart phone. First, the basic concept of LBS is introduced. Second, the state-of-the-art smart phones and communication networks are described. Afterwards, the smart phone positioning technologies are presented as three groups: satellite-based technologies, network-based solutions, and sensor-based approaches. Then, the location relevant services, contents, data, and context in a smart phone are explained. Furthermore, in the perspective of the new generation of LBS, the emerging features and technical solutions are discussed. Finally, three examples show how the above elements are integrated into the LBS applications in a smart phone.

Opportunistic sensing in hydrometeorology

2020 ◽  
Author(s):  
Remko Uijlenhoet ◽  
Lotte de Vos ◽  
Aart Overeem ◽  
Hidde Leijnse
Keyword(s):  
High Resolution ◽  
Communication Networks ◽  
Urban Areas ◽  
Rapid Development ◽  
Measurement Techniques ◽  
Statistical Treatment ◽  
The State ◽  
International Standards ◽  
Measurement Equipment ◽  
Opportunistic Sensing

<p>Traditionally, hydrologists have relied on dedicated measurement equipment to do their business (e.g. rainfall-runoff modeling). Such instruments are typically owned and operated by government agencies and regional or local authorities. Installed and maintained according to (inter)national standards, they offer accurate and reliable information about the state of and fluxes in the hydrological systems we study as scientists or manage as operational agencies. Such standard instruments are often further developments of novel measurement techniques which have their origins in the research community and have been tested during dedicated field campaigns.</p><p>One drawback of the operational measurement networks available to the hydrological community today is that they often lack the required coverage and spatial and/or temporal resolution for high-resolution real-time monitoring or short-term forecasting of rapidly responding hydrological systems (e.g. urban areas). Another drawback is that dedicated networks are often costly to install and maintain, which makes it a challenge for nations in the developing world to operate them on a continuous basis, for instance.</p><p>Yet, our world is nowadays full of sensors, often related to the rapid development in wireless communication networks we are currently witnessing (notably 5G). Let us try to make use of such opportunistic sensors to do our (hydrologic) science and our (water management) operations. They may not be as accurate or reliable as the dedicated measurement equipment we are used to working with, let alone meet official international standards, but they typically come in large numbers and are accessible online. Hence, in combination with smart retrieval algorithms and statistical treatment, opportunistic sensors may provide a valuable complementary source of information regarding the state of our environment.</p><p>The presentation will focus on some recent examples of the potential of opportunistic sensing techniques in hydrology and water resources, from rainfall monitoring using microwave links from cellular communication networks (in Europe, South America, Africa and Asia), via crowdsourcing urban air temperatures using smartphone battery temperatures to high-resolution urban rainfall monitoring using personal weather stations.</p>

scholarly journals Trade Integration and Communication Networks in Latin America

1995 ◽  
Vol 20 (3) ◽  
Author(s):  
Rafael Roncagliolo
Keyword(s):  
Latin America ◽  
Trade Liberalization ◽  
Communication Networks ◽  
Latin American ◽  
The State ◽  
Point Of View ◽  
Homogeneous Group ◽  
Trade Integration ◽  
The World ◽  
Single Process

Abstract: Over the last few years, academic discussions about the state of communications in the Americas, particularly those discussions taking place in the northern part of the continent, sometimes slide into one or more of the following misunderstandings: the provincialist view, which considers the entire hemisphere to be involved in a single process of trade liberalization, like the NAFTA; the overly simplified view, which assumes that the southern countries are a homogeneous group, from the point of view of cultural and technical vistas; the belief that there has been no effort to integrate these countries' communications; and the globalist view, which aims at forgetting the profound peculiarities which radically differentiate American communications from those of the rest of the world. Keeping in mind these traps and dangers, in this presentation I would like to specify that there exist not one but many processes of trade liberalization affecting the Americas; introduce a view of the internal complexity and heterogeneity of the region; enumerate prior Latin American attempts at communications integration, looking at materials and goals; and present three peculiarities which differentiate the region from the rest of the world. Résumé: Depuis quelques années, les discussions académiques sur les communications dans les Amériques, particulièrement celles ayant lieu dans la moitié nord de ces continents, s'empêtrent parfois dans un ou plusieurs des quatre malentendus suivants: la perspective "provincialiste", qui croit que l'hémisphère entier est en train de s'engager dans un seul grand processus de libéralisation d'échange, à l'instar de l'Accord de libre-échange nord-américain; la perspective simpliste à l'excès, qui suppose que les pays du Sud sont homogènes, tant du point de vue culturel que technique; la croyance qu'il n'y a eu aucun effort d'associer les communications dans ces divers pays; et la perspective "globalisante", qui oublie les particularités profondes qui rendent les communications nord- et sud-américaines radicalement différentes de celles du reste du monde. Tenant compte de ces pièges et dangers, nous aimerions dans cet article spécifier qu'il n'existe pas qu'un seul processus de libéralisation d'échange touchant les Amériques, mais bien plusieurs; souligner la complexité interne et l'hétérogénéité de la région; décrire des tentatives antérieures en Amérique latine d'intégrer les communications, en se concentrant sur matériaux et objectifs; et présenter quelques unes des caractéristiques qui distinguent cette région du reste du monde.

The State and Community-Based Projects of Environmental Conservation in Promoting Mountain Ecotourism in Lesotho

2020 ◽  
pp. 245-262
Author(s):  
Tšepiso Augustinus Rantšo ◽  
Khotso Ketsi
Keyword(s):  
Decision Making ◽  
Communication Networks ◽  
National Parks ◽  
Environmental Conservation ◽  
The State ◽  
Environmental Resources ◽  
Top Down ◽  
Community Based ◽  
Ecological Zones ◽  
Private Entrepreneurs

Lesotho is divided into four ecological zones, the Highlands, the Foot Hills, the Senqu River Valley, and the Lowlands. Many people in these geographic areas are faced with poverty, unemployment, and other social problems. As a result, they exploit the natural environment for making a living. To conserve the endangered natural species and promote mountain ecotourism, the Lesotho Government established national parks and nature reserves. These state-owned national parks followed a top-down approach where the locals were not involved in the decision-making. Thus, these were subjected to vandalism from communities in the adjacent areas. Some locals have established botanical gardens to conserve environmental resources, thus promoting mountain ecotourism. The state, NGOs, and private entrepreneurs support community-based projects of environmental conservation and mountain ecotourism. While some of the destinations have resulted in establishment of communication networks, many places in the Highlands remain inaccessible and thus negatively impact mountain ecotourism.

Management of geotourism stakeholders experiences from the Network History of the Earth

2010 ◽  
Author(s):  
Christof Pforr ◽  
Andreas Megerle
Keyword(s):  
Sustainable Development ◽  
Communication Networks ◽  
Effective Communication ◽  
The State ◽  
West Germany ◽  
Black Forest ◽  
Public And Private ◽  
The Earth ◽  
South West ◽  
History Of

A sharp increase in interest in geotourism worldwide in recent years has transformed many suitable regions into unique geotourism destinations opening up great opportunities for geoconservation and regional sustainable development. To fully capitalize on this potential, however, it is essential to bring together the fragmented stakeholders from the public and private sectors and establish appropriate structures and processes to facilitate their effective communication and collaboration. Only through such a partnership can an adequate knowledge base, built on diverse experiences and expertise, be established to provide certainty and guidance in the sustainable development of local geotourism products. Thus, effective communication networks and an open exchange of information are cornerstones of a successful implementation of geotourism in a region. The Network History of the Earth is a case in point for such a successful geotourism partnership. It was founded in 1997 as a framework for cooperation between a range of diverse stakeholders working together to develop a high quality sustainable tourism product based on the unique georesources of South-West Germany (Pforr and Megerle, 2006). South-West Germany mainly comprises the State of Baden-Württemberg and covers an area of 35,752 square kilometres with a population of around 10.7 million people (see Figure 8.3). A typical feature of the state is its wide variety of natural landscapes which can be subdivided into three main landforms, the Upper Rhine Graben (Oberrheingraben) in the west surrounded by the Black Forest (Schwarzwald) in the east and the Vosges Mountains (Vogesen) on the western French side, the southwestern cuesta landscape (Schichtstufenland) gently sloping towards the south-east as well as the Alpine piedmont (Alpenvorland). These diverse and distinct landscapes form the resource base of tourism, and, in some cases, like the jurassic geopark Swabian Alb and the mining areas of the Black Forest, also for geotourism (Geyer and Megerle, 2003). The service sector industries contribute almost 34 per cent to the state’s economic activities with tourism being an important industry for the state in general, but especially economically significant for regional areas.

Some new results on queueing networks with batch movement

1991 ◽  
Vol 28 (02) ◽  
pp. 409-421 ◽  
Author(s):  
W. Henderson ◽  
P. G. Taylor
Keyword(s):  
Continuous Time ◽  
Queueing Networks ◽  
Equilibrium Distribution ◽  
Product Form ◽  
Batch Arrivals ◽  
Before And After ◽  
Equilibrium Distributions ◽  
Batch Services ◽  
Independence Results ◽  
Networks Of Queues

Product-form equilibrium distributions in networks of queues in which customers move singly have been known since 1957, when Jackson derived some surprising independence results. A product-form equilibrium distribution has also recently been shown to be valid for certain queueing networks with batch arrivals, batch services and even correlated routing. This paper derives the joint equilibrium distribution of states immediately before and after a batch of customers is released into the network. The results are valid for either discrete- or continuous-time queueing networks: previously obtained results can be seen as marginal distributions within a more general framework. A generalisation of the classical ‘arrival theorem' for continuous-time networks is given, which compares the equilibrium distribution as seen by arrivals to the time-averaged equilibrium distribution.

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