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1 – 10 of over 4000This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog and…
Abstract
This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog and digital signals, synchronous and asynchronous transmission formats, transmission media and equipment, transmission techniques and characteristics, multiplexing, network types, access technologies, network architectures and topologies, local‐area network technologies and attributes, protocols and protocol issues, gateways, internetworking, local networking alternatives, equipment certification, and various aspects of network management. It is intended to provide the practicing professional in the field of library and information science with a broad, up‐to‐date technical review that might serve to support and facilitate further investigation of current developments in networks and networking. Although the broad range of topics is not treated in depth, numerous references are provided for further investigation.
Amitava Ghosal and Raja Ghosal
Computer networks are very complex and somewhat unpredictable systems in dynamic operations. Cybernetic modelling, incorporating stochastic, fuzzy variables, wherever appropriate…
Abstract
Computer networks are very complex and somewhat unpredictable systems in dynamic operations. Cybernetic modelling, incorporating stochastic, fuzzy variables, wherever appropriate, approximating interactions not easily tractable via a black‐box systems approach, may be more accurate. A method of analysis of computer networks is considered by representing subsystems and interactions, accurately as far as possible, and then utilising the results of systems sciences for analysis, including specifics, e.g. queuing systems. The aim is to identify correspondences between the behaviour of subsystems of networks and suitable analytic tools. Automation along such lines for the analysis and design of networks and other systems may be a possibility.
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Since the 1950s early adopters of a succession of new technologies have been working to see how these could be exploited in the language learning field. However, this pioneering…
Abstract
Since the 1950s early adopters of a succession of new technologies have been working to see how these could be exploited in the language learning field. However, this pioneering work has had relatively little impact on the teaching and learning of languages. Is this pattern going to be repeated with the introduction of network technologies into language education? Raises some key themes which need attention if this cycle is to be broken. The central questions are: Why should language teachers be trying to integrate the use of network technologies into their curricula? If they should, how can this be achieved? To support this discussion recent experimental work in the area is described and considered. Concludes by stressing the need for skilful management of technological innovation in the education sector, and the importance of applying sound pedagogical principles.
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The authors consider parallel four-state tandem open queueing network. The queue capacity is infinite. Passenger arrival rate is Poisson distribution and service rate is…
Abstract
Purpose
The authors consider parallel four-state tandem open queueing network. The queue capacity is infinite. Passenger arrival rate is Poisson distribution and service rate is exponential distribution. The queue is constructed in the form of tandem queue, and each and every queue of tandem queue is single server (M/M/1) queue. In tandem queue, passengers will leave the system once they receive service from both the states. The purpose of this paper is to provide performance analysis for four-state tandem open queue network, and a governing equation is formulated with the help of transition diagram. Using Burke theorem, the authors formulated equation for average number of passenger in the system, average waiting time of passenger in the system, average number of passenger in the queue and average waiting time of passenger in the queue.
Design/methodology/approach
This paper used Burke’s theorem.
Findings
In this paper, performance analysis is done for parallel four-state tandem open queueing network and performance measure solved using Burkes theorem formula. K. Sreekanth et al. has done performance analysis for single tandem queue with three states. In this paper, the authors have done performance analysis for two tandem queues parallel with four states. This four-state tandem open queueing network is suitable for real world applications. This paper can extend for more number of service states and multi-server states according to the application, and in such case, the authors have to prove and explain with numerical examples. This analysis is more useful for the applications such as airports, railway stations, bus-stands and banks.
Originality/value
In this paper, parallel four-state tandem open queueing network and performance measure has been solved using Burke’s theorem formula.
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Anand Jaiswal, Cherian Samuel and Chirag Chandan Mishra
The purpose of this paper is to provide a traffic route selection strategy based on minimum carbon dioxide (CO2) emission by vehicles over different route choices.
Abstract
Purpose
The purpose of this paper is to provide a traffic route selection strategy based on minimum carbon dioxide (CO2) emission by vehicles over different route choices.
Design/methodology/approach
The study used queuing theory for Markovian M/M/1 model over the road junctions to assess total time spent over each of the junctions for a route with junctions in tandem. With parameters of distance, mean service rate at the junction, the number of junctions and fuel consumption rate, which is a function of variable average speed, the CO2 emission is estimated over each of the junction in tandem and collectively over each of the routes.
Findings
The outcome of the study is a mathematical formulation, using queuing theory to estimate CO2 emissions over different route choices. Research finding estimated total time spent and subsequent CO2 emission for mean arrival rates of vehicles at junctions in tandem. The model is validated with a pilot study, and the result shows the best vehicular route choice with minimum CO2 emissions.
Research limitations/implications
Proposed study is limited to M/M/1 model at each of the junction, with no defection of vehicles. The study is also limited to a constant mean arrival rate at each of the junction.
Practical implications
The work can be used to define strategies to route vehicles on different route choices to reduce minimum vehicular CO2 emissions.
Originality/value
Proposed work gives a solution for minimising carbon emission over routes with unsignalised junctions in the tandem network.
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The National Bibliographic Information Network (NBINet) in Taiwan is a bibliographic database established on 30 October 1991 and maintained by the National Central Library. In…
Abstract
The National Bibliographic Information Network (NBINet) in Taiwan is a bibliographic database established on 30 October 1991 and maintained by the National Central Library. In 1998 there were 26 member libraries and 70 non‐member libraries in NBINet, which is considered a comprehensive database for Chinese studies worldwide and contains more than 1.6 million bibliographic records. This paper discusses the problems encountered in the establishment of NBINet and the solutions related to computers and networks, NBINet’s utilization on the Internet, and user expectations of NBINet.
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Fiona Eva Bakas, Nancy Duxbury and Tiago Vinagre de Castro
Given limited research about how artisans become integrated into tourism, the purpose of this paper is to investigate the emergence of artisan entrepreneur–mediators who link…
Abstract
Purpose
Given limited research about how artisans become integrated into tourism, the purpose of this paper is to investigate the emergence of artisan entrepreneur–mediators who link artisans to tourism in rural areas and small cities in Portugal. Using social embeddedness as a conceptual framework, this paper views artisan entrepreneur–mediators as existing within an entrepreneurial ecosystem. The paper investigates their role within this ecosystem and how social networks influence the artisan entrepreneur–mediators’ roles in connecting artisans to creative tourism.
Design/methodology/approach
The paper is based on new (2017 and 2018) empirical evidence developed through two rounds of semi-structured interviews of five artisan entrepreneur–mediators.
Findings
This paper finds that artisan entrepreneur–mediators in rural areas or small cities take on multiple roles as networking agents who organize and offer creative tourism experiences, providing the missing link between artisans and tourists. An analysis of the nuances of the operations of these artisan entrepreneur–mediators suggests that high levels of social embeddedness within local rural communities are important in order for these neo-rural entrepreneurs to attain their goals.
Originality/value
Originality lies in the identification of a gap in artisan entrepreneurship literature in a rural context. It is the first time that a critical analysis of artisan entrepreneur–mediators who facilitate the link between artisans and tourism is carried out in terms of social embeddedness, their roles and connections to creative tourism, and types of community engagement.
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In 1983, Utlas International, a major bibliographic utility and a vendor of a range of automated services and systems for the library community, reached a point in its corporate…
Abstract
In 1983, Utlas International, a major bibliographic utility and a vendor of a range of automated services and systems for the library community, reached a point in its corporate development where massive technological change was unavoidable. Feuer details the procedures adopted by Utlas to migrate to a next‐generation system. The process involved three major stages: planning, system conversion, and implementation. He notes techniques employed to keep sub‐tasks manageable, to maintain a schedule, to instill a sense of accomplishment in staff members, to facilitate communications among project teams and all individual staff members, and to extract that most necessary and elusive component of a major development effort—documentation. The experiences in this case study are relevant to libraries that are implementing new systems, and particularly to those libraries that are migrating to next‐generation technologies.
Network analysis is a well consolidated research area in several disciplines. Within management and organizational studies, network scholars consolidated a set of research…
Abstract
Purpose
Network analysis is a well consolidated research area in several disciplines. Within management and organizational studies, network scholars consolidated a set of research practices that allowed ease of data collection, high inter case comparability, establishment of nomological laws and commitment to social capital motivation. This paper aims to elicit the criticism it has received and highlight the unsettled lacunae.
Design/methodology/approach
This paper sheds light on Network Analysis’s breakthroughs, while showing how its scholars innovated by responding to critics, and identifying outstanding debates.
Findings
The paper identifies and discusses three streams of criticism that are still outstanding: the role of human agency, the meaning of social ties and the treatment of temporality.
Originality/value
This paper brings to fore current debates within the Network Analysis community, highlighting areas where future studies might contribute.
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The aim of this paper is to develop an efficient analytical procedure to evaluate performance of the most general pull production systems particularly when multiple‐part‐types are…
Abstract
Purpose
The aim of this paper is to develop an efficient analytical procedure to evaluate performance of the most general pull production systems particularly when multiple‐part‐types are involved. The authors consider a kanban controlled production system that can be modelled as a closed queuing network with different product classes. The production line is decomposed into stages which consist of one or several stations and an output buffer. Each stage is associated with a given number of kanbans. The main idea of this analytical algorithm is to analyze each subnetwork individually using a product form approximation technique. The iterative procedure is used to find the unknown parameters.
Design/methodology/approach
The authors design a multiclass queuing network that can be used to represent kanban controlled production systems. To solve this model, three procedures are used: decompose the original network into M subnetworks, convergence of unknown parameters in each subnetwork, and convergence of unknown parameters in the original network. The authors now describe these procedures separately.
Findings
The main contribution of this paper is the formulation of the problem of kanban controlled production systems with several part‐types. The methodology is based on approximate formula with decomposition and is applicable to more general manufacturing environments. The authors' method can be applied to both limited and unlimited demands. The analytical algorithm designed in this work has demonstrated excellent performance in analyzing kanban controlled production systems.
Originality/value
The methodology of this algorithm is based on approximate formula and is applicable to more general manufacturing environments.
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