De touch: extending service channels in an airport through touch technologies

This project aimed to create a communication and interaction channel between Madeira Airport and its passengers. We used the pre-existent touch enabled screens at the terminal since their potential was not being utilised to their full capacity. To achieve our goal, we have followed an agile strategy to create a testable prototype and take advantages of its results. The developed prototype is based on a plugin architecture turning it into a maintainable and highly customisable system. The collected usage data suggests that we have achieved the initially defined goals. There is no doubt that this new interaction channel is an improvement regarding the provided services and, supported by the usage data, there is an opportunity to explore additional developments to the channel.

Autonomous guided vehicles applied to industrial engineering and management studies

This article presents a framework to an Industrial Engineering and Management Science course from School of Management and Industrial Studies using Autonomous Ground Vehicles (AGV) to supply materials to a production line as an experimental setup for the students to acquire knowledge in the production robotics area. The students must be capable to understand and put into good use several concepts that will be of utmost importance in their professional life such as critical decisions regarding the study, development and implementation of a production line. The main focus is a production line using AGVs, where the students are required to address several topics such as: sensors actuators, controllers and an high level management and optimization software. The presented framework brings to the robotics teaching community methodologies that allow students from different backgrounds, that normally don’t experiment with the robotics concepts in practice due to the big gap between theory and practice, to go straight to ”making” robotics. Our aim was to suppress the minimum start point level thus allowing any student to fully experience robotics with little background knowledge.

Análise e implementação de melhorias no serviço Pós-Venda na área automóvel

No âmbito da unidade curricular de Dissertação/Projeto/Estágio, pertencente ao segundo ano do Mestrado em Engenharia Mecânica – Ramo de Gestão Industrial do Instituto Superior de Engenharia do Porto, o presente trabalho foi desenvolvido no Grupo JAP, Grupo do setor automóvel, desenvolvido especificamente no serviço pós-venda. Numa realidade bastante diferente de outros tempos onde havia grandes margens com a venda de produtos, hoje a realidade é bem diferente. Num contexto de competição global onde as margens são mais reduzidas, o serviço pós-venda, onde o cliente é acompanhado desde da compra até o fim de vida do produto, constitui uma fonte de receitas relevante bem como um diferenciador chave dentre as empresas de revenda automóvel. Por estas razões, são cada vez mais as empresas que seguem a filosofia Lean, orientando toda a sua estrutura produtiva no sentido de atingir zero desperdícios, sem interferir com a qualidade do produto final. A realização deste projeto teve como objetivo o desenvolvimento e adequação de ferramentas de melhoria e apoio ao serviço pós-venda no Grupo. Com a elaboração deste trabalho, pretende-se fazer uma análise a todo o processo do serviço pós-venda, identificando os problemas que ocorrem ao longo do processo e desenvolver um plano de ações de melhoria, utilizando para isso as ferramentas da metodologia Lean. Em primeiro lugar, fez-se uma análise do processo do serviço pós-venda e do serviço do armazém de peças, onde foram identificados alguns pontos de melhoria e recolhidos as primeiras informações para uma análise mais aprofundada de cada problema. Posteriormente, estabeleceu-se um plano de ações para eliminar ou minimizar os desperdícios encontrados no processo, aumentar a produtividade e a qualidade do serviço prestado ao cliente, e procedeu-se à implementação das melhorias. Após a implementação das melhorias, fez-se uma avaliação das mesmas e constatou-se um aumento de produtividade, uma redução de desperdícios e um aumento dos índices de qualidade. Em suma uma melhoria no serviço prestado ao cliente.

Using life strategies to explore the vulnerability of ecosystem services to invasion by alien plants

Invasive plants can have different effects of ecosystem functioning and on the provision of ecosystem services, from strongly deleterious impacts to positive effects. The nature and intensity of such effects will depend on the service and ecosystem being considered, but also on features of life strategies of invaders that influence their invasiveness as well as their influence of key processes of receiving ecosystems. To address the combined effect of these various factors we developed a robust and efficient methodological framework that allows to identify areas of possible conflict between ecosystem services and alien invasive plants, considering interactions between landscape invasibility and species invasiveness. Our framework combines the statistical robustness of multi-model inference, efficient techniques to map ecosystem services, and life strategies as a functional link between invasion, functional changes and potential provision of services by invaded ecosystems. The framework was applied to a test region in Portugal, for which we could successfully predict the current patterns of plant invasion, of ecosystem service provision, and finally of probable conflict (expressing concern for negative impacts, and value for positive impacts on services) between alien species richness (total and per plant life strategy) and the potential provision of selected services. Potential conflicts were identified for all combinations of plant strategy and ecosystem service, with an emphasis for those concerning conflicts with carbon sequestration, water regulation and wood production. Lower levels of conflict were obtained between invasive plant strategies and the habitat for biodiversity supporting service. The added value of the proposed framework in the context of landscape management and planning is discussed in perspective of anticipation of conflicts, mitigation of negative impacts, and potentiation of positive effects of plant invasions on ecosystems and their services.

Le suicide comme langage de l'oppression. Ethnographie d'un service d'urgences psychiatriques

Ce travail s'intéresse à la problématique du suicide à partir de l'émergence en Suisse, vers la fin des années '90, de la prévention du suicide comme préoccupation sociale et politique. Au début, ce sont les milieux associatifs qui ont soulevé à cette question en percevant le suicide comme le reflet d'une souffrance d'origine sociale. Par la suite, la prévention du suicide est progressivement devenue une problématique de santé publique appréhendée essentiellement sous le registre médical comme étant le symptôme d'une pathologie psychiatrique. Après une première partie consacrée aux processus sociopolitiques et aux transformations morales touchant le suicide et sa prévention, ce travail approfondit, au travers d'un terrain ethnographique, la prise en charge des personnes présentant des problématiques suicidaires au sein d'un service d'urgences psychiatriques.Malgré une approche se voulant biopsychosociale, l'analyse des discours et des pratiques soignantes montre que la dimension sociale est largement négligée, conduisant à une médicalisation de situations de détresse qui sont principalement de nature sociale. En effet, parmi la population qui fréquente le service, on observe une surreprésentation de personnes issues des classes sociales défavorisées présentant souvent des trajectoires biographiques particulièrement difficiles. Au fil des entretiens avec les patients émerge une analyse voyant la souffrance psychique et la prise en charge psychiatrique comme étant aujourd'hui une manière d'obtenir une reconnaissance sociale et symbolique. Les problématiques suicidaires peuvent ainsi être interprétées comme une forme d'expression, un langage au travers duquel s'exprime la position sociale défavorisée.En adoptant une posture militante construite à partir de la réalité ethnographique, les problématiques suicidaires sont analysées comme l'expression d'une condition d'oppression liée à un cadre social et économique de plus en plus contraignant, à des rapports de pouvoir inégaux ainsi qu'à une lecture individualisante, médicalisante et pathologisante des problèmes sociaux.The present thesis discusses suicide prevention in Switzerland, which emerged as a social and political issue at the end of the '90s. At first, this question was taken up by associations considering suicide as a reflection of social suffering. Thereafter, suicide prevention gradually became a public health matter conceived with a medical approach as a symptom of a psychiatric disease. The first part of this work analyzes the sociopolitical process and moral transformations concerning suicide and its prevention. The second part is based on an ethnographic fieldwork conducted in a psychiatric emergency unit that attends people who have tried to attempt their life or consider doing it. Through the analysis of discourses and practices of the medical staff, this research shows that the social aspect of suicide is widely neglected, leading to a medicalization of social problems. In fact, amongst patients attending the emergency unit, there is an over-­-representation of people from disadvantaged classes having very difficult life stories. Interviews with patients also revealed that psychic suffering and psychiatric treatment is nowadays a way to get social and symbolical recognition. Suicidal problems can be understood as a language expressing a disadvantaged social position. By adopting a militant position constructed from the ethnographic reality, suicide is analyzed as the expression of an oppressed condition related to a more and more restricted social and economic situation, to unequal power relations as well as to an individualistic, medical and pathological interpretation of social problems.

The quality of life in the Master of Education program, Brock University

This study addressed the problem of the quality of life in the Brock Master of Education program. Survey and interview data were used to gain an understanding of satisfaction with the learning achieved and student life experienced. Eighty-seven percent of the study sample reported satisfaction with the program overall. Results suggested the higher the overall satisfaction with a program, the greater the likelihood learning and student life satisfaction were also more positive. Student reflections suggested satisfaction with the quality of life in the program was associated with the program's focus on the student, the use of self-directed learning, and the support of professors to meet student needs. Comparison of the Brock Master of Education survey with the Brock Pre-Service Teacher Education program showed both student groups shared a similar satisfaction with student life in the Faculty. Comparison of Master of Education programs suggested the difference between two programs, a difference which may be influenced by time in the program. The results from the three programs suggested that students beyond the first undergraduate degree favored the school domains of learning acquisition. Supplementary data on the relationship between cognitive and affective opinions suggested the more positive the affective dimension of learning, the greater the likelihood the cognitive dimensions of student life were also more positive. It was concluded that time was a chief factor influencing part-time student satisfaction with both learning and student life in the program. Part-time students, as. the majority in the survey, expressed comments about the need for clarity of communication between the organization and student to promote the effective use of limited time.

Investigation of Changes in Prescribed and Voluntary Job Roles in Community Service Delivery for People who have Intellectual Disabilities after the Implementation of the 3 Rs; Rights, Respect and Responsibility Project

The purpose of this thesis was to explore whether there is change in organizational citizenship behaviours in community agency staff following agency adoption of a rights - based service philosophy. Four community agency support staff were interviewed to investigate how residential care providers in services for persons who have intellectual disabilities describe their voluntary job related behaviours following training about human rights. The major finding was that the participants were actively engaged in displaying civic virtue, courtesy, and altruism discretionary behaviours. There was evidence of a post rights training shift in communication patterns with support staff reporting that they used language that prom,oted and advocated for human rights, and reported increased communication exchanges among persons supported by the agency, support staff and managers. Participants also suggested that the individuals they support asserted their rights more frequently and they were more active in their own life choices following rights training.

The Influence of Burnout Symptoms on the Relationship between Work-Life Balance and Self-Rated Health

The effects of stress at work are estimated to cost Canadian employers more than 20 billion dollars annually through absenteeism, sick leave and decreased productivity. Over the past two decades, Canadians have reported higher stress levels, increased work hours and more work performed outside of normal business hours. This work-life imbalance has far-reaching repercussions–affecting an employee’s performance as well as their health. Chronic exposure to these high levels of stress can also lead to burnout. The primary purpose of this study was to determine the magnitude in which burnout symptoms influence the relationship between work-life balance and self-rated health. The secondary purpose of this study was to determine if gender and age interactions exist in the relationship between burnout, work-life balance, and self-rated health. This cross-sectional study involved secondary analysis of 220 managers, workers and human service professionals who completed an Occupational Health Clinics for Ontario Workers’ Mental Injury Toolkit (MIT) survey for the launch of the MIT. The MIT survey is a modified form of the short version of the Copenhagen Psychosocial Questionnaire and includes expanded questioning around burnout, stress, sleep troubles, cognitive, and somatic symptoms. There were no significant differences in self-rated health based on a respondent’s gender or age, indicating that no interaction of gender and age would be required. Respondents with low self-rated health reported significantly higher burnout and work-life imbalance compared to those with high self-rated health. The regression analysis demonstrated that the magnitude in which burnout mediates the relationship between work-life balance and self-rated health was 96%. These findings support previous studies that associate high levels of work-life imbalance or burnout with poor self-rated health or health outcomes. In this study, the shared variance between work-life balance and burnout also supports recent efforts to redefine the context and causes of burnout to include non-work factors. Based on our findings, the potential exists for the development of workplace health promotion strategies that address maintaining a balance between work and home as they may improve employee health and reduce burnout.

Scheduled service network design for integrated planning of rail freight transportation

Cette thèse étudie une approche intégrant la gestion de l’horaire et la conception de réseaux de services pour le transport ferroviaire de marchandises. Le transport par rail s’articule autour d’une structure à deux niveaux de consolidation où l’affectation des wagons aux blocs ainsi que des blocs aux services représentent des décisions qui complexifient grandement la gestion des opérations. Dans cette thèse, les deux processus de consolidation ainsi que l’horaire d’exploitation sont étudiés simultanément. La résolution de ce problème permet d’identifier un plan d’exploitation rentable comprenant les politiques de blocage, le routage et l’horaire des trains, de même que l’habillage ainsi que l’affectation du traffic. Afin de décrire les différentes activités ferroviaires au niveau tactique, nous étendons le réseau physique et construisons une structure de réseau espace-temps comprenant trois couches dans lequel la dimension liée au temps prend en considération les impacts temporels sur les opérations. De plus, les opérations relatives aux trains, blocs et wagons sont décrites par différentes couches. Sur la base de cette structure de réseau, nous modélisons ce problème de planification ferroviaire comme un problème de conception de réseaux de services. Le modèle proposé se formule comme un programme mathématique en variables mixtes. Ce dernie r s’avère très difficile à résoudre en raison de la grande taille des instances traitées et de sa complexité intrinsèque. Trois versions sont étudiées : le modèle simplifié (comprenant des services directs uniquement), le modèle complet (comprenant des services directs et multi-arrêts), ainsi qu’un modèle complet à très grande échelle. Plusieurs heuristiques sont développées afin d’obtenir de bonnes solutions en des temps de calcul raisonnables. Premièrement, un cas particulier avec services directs est analysé. En considérant une cara ctéristique spécifique du problème de conception de réseaux de services directs nous développons un nouvel algorithme de recherche avec tabous. Un voisinage par cycles est privilégié à cet effet. Celui-ci est basé sur la distribution du flot circulant sur les blocs selon les cycles issus du réseau résiduel. Un algorithme basé sur l’ajustement de pente est développé pour le modèle complet, et nous proposons une nouvelle méthode, appelée recherche ellipsoidale, permettant d’améliorer davantage la qualité de la solution. La recherche ellipsoidale combine les bonnes solutions admissibles générées par l’algorithme d’ajustement de pente, et regroupe les caractéristiques des bonnes solutions afin de créer un problème élite qui est résolu de facon exacte à l’aide d’un logiciel commercial. L’heuristique tire donc avantage de la vitesse de convergence de l’algorithme d’ajustement de pente et de la qualité de solution de la recherche ellipsoidale. Les tests numériques illustrent l’efficacité de l’heuristique proposée. En outre, l’algorithme représente une alternative intéressante afin de résoudre le problème simplifié. Enfin, nous étudions le modèle complet à très grande échelle. Une heuristique hybride est développée en intégrant les idées de l’algorithme précédemment décrit et la génération de colonnes. Nous proposons une nouvelle procédure d’ajustement de pente où, par rapport à l’ancienne, seule l’approximation des couts liés aux services est considérée. La nouvelle approche d’ajustement de pente sépare ainsi les décisions associées aux blocs et aux services afin de fournir une décomposition naturelle du problème. Les résultats numériques obtenus montrent que l’algorithme est en mesure d’identifier des solutions de qualité dans un contexte visant la résolution d’instances réelles.

Quand la toile porte l’étoile : L’Internet au service de la Charte internationale des droits de l’homme

Le réseau Internet a probablement causé un tourbillon économique et social sans équivalent dans l’histoire du monde moderne. De tels bouleversements ont amené plusieurs personnes à s’interroger sur la puissance de cet outil, sa liberté et son impact sur l’humanité. Nombreux sont ceux qui ont ainsi voulu attribuer à l’Internet un rôle primordial dans l’ensemble des maux de notre siècle, notamment en l’accusant de favoriser la propagation des messages de haine, la perversion des mœurs et le contournement de la loi. L’auteur se propose ici de prendre le contre-pied de ce courant pessimiste, et de faire la démonstration des avancées considérables que cet outil merveilleux a permises dans le domaine des droits économiques et sociaux. En s’appuyant sur les textes internationaux ayant donné naissance à ces droits voulus pragmatiques, l’auteur précise d’abord le contenu de prérogatives qui concernent directement le quotidien de chacun, sans pour autant faire l’objet d’une réelle application. Il met ensuite en parallèle l’objectif initial recherché par le législateur international et les avancées concrètes permises par le réseau dans des domaines aussi variés que la liberté d’expression, l’accès au droit, et la participation de tous à la vie culturelle et politique de la société. Cet article est une tentative de redonner au réseau ses lettres de noblesse, et d’encourager les lecteurs à utiliser mieux encore ses fantastiques ressources.

Coral Reef Ecosystem of Lakshadweep Archipelago –A Biogeochemical Facsimile

The present study focuses on the biochemical aspects of six islands belonging to Lakshadweep Archipelago – namely Kavaratti, Kadamath, Kiltan, Androth, Agathy and Minicoy. Lakshadweep, which is an area biologically significant due to isolation from the major coastline, remains as one of the least studied areas in Indian Ocean. The work, processed out the distributional pattern of trace metals among the biotic (corols, sea weeds and sea grass) and abiotic component (sediments) of ecosystem. An effort is made to picturise the spatial distribution pattern of different forms of nitrogen and phosphorus in the various sedimentary environments of the study area. Studies on the biogeochemical and nutrient aspects of the concerned study area scanty. In Lakshadweep, the local life is very dependent on reefs and its resources. The important stress which produce a threatening effort on the existence for coral reefs are anthropogenic-namely-organic and inorganic pollution from sewage, agricultural and industrial waters, sediment damage from excessive land cleaning, and over exploitation particularly through destructive fishing methods. In addition these one other more localized or less service anthropogenic stress: pollution by oil and other hydrocarbons, complex organic molecular and heavy metal pollution, and destructive engineering practices.

Marine Engineering Training in India -A Pedagogic Introspection

Indian marine engineers are renowned for employment globally due to their knowledge, skill and reliability. This praiseworthy status has been achieved mainly due to the systematic training imparted to marine engineering cadets. However, in an era of advancing technology, marine engineering training has to remain dynamic to imbibe latest technology as well as to meet the demands of the shipping industry. New subjects of studies have to be included in the curriculum in a timely manner taking into consideration the industry requirements and best practices in shipping. Technical competence of marine engineers also has to be subjected to changes depending upon the needs of the ever growing and over regulated shipping industry. Besides. certain soft skills are to be developed and improved amongst the marine engineers in order to alter or amend the personality traits leading to their career success.If timely corrective action is taken. Indian marine engineers can be in still greater demand for employment in global maritime field. In order to enhance the employability of our mmine engineers by improving their quality, a study of marine engineers in general and class IV marine engineers in particular was conducted based on three distinct surveys, viz., survey among senior marine engineers, survey among employers of marine engineers and survey of class IV marine engineers themselves.The surveys have been planned and questionnaires have been designed to focus the study of marine engineer officer class IV from the point of view of the three distinct groups of maritime personnels. As a result of this, the strength and weakness of class IV marine engineers are identified with regard to their performance on board ships, acquisition of necessary technical skills. employability and career success. The criteria of essential qualities of a marine engineer are classified as academic, technical, social, psychological. physical, mental, emergency responsive, communicative and leadership, and have been assessed for a practicing marine engineer by statistical analysis of data collected from surveys. These are assessed for class IV marine engineers from the point of view of senior marine engineers and employers separately. The Endings are delineated and graphically depicted in this thesis.Besides. six pertinent personality traits of a marine engineer viz. self esteem. learning style. decision making. motivation. team work and listening self inventory have been subjected to study and their correlation with career success have been established wherever possible. This is carried out to develop a theoretical framework to understand what leads a marine engineer to his career attainment. This enables the author to estimate the personality strengths and weaknesses of a serving marine engineer and eventually to deduce possible corrective measures or modifications in marine engineering training in India.Maritime training is largely based on International Conventions on Standard of Training. Certification and Watch keeping for Seafarers 1995. its associated Code and Merchant Shipping (STCW for Seafarers) Rules 1998. Further, Maritime Education, Training and Assessment (META) Manual was subjected to a critical scrutiny and relevant Endings of thc surveys arc superimposed on the existing rule requirement and curriculum. Views of senior marine engineers and executives of various shipping companies are taken into account before arriving at the revision of syllabus of marine engineering courses. Modifications in the pattern of workshop and sea service for graduate mechanical engineering trainees are recommended. Desirable age brackets of junior engineers and chief engineers. use of Training and Assessment Record book (TAR Book) during training etc. have also been evaluated.As a result of the pedagogic introspection of the existing system of marine engineering training in India. in this thesis, a revised pattern of workshop training of six months duration for graduate mechanical engineers. revised pattern of sea service training of one year duration and modified now diagram incorporating the above have been arrived at. Effects of various personality traits on career success have been established along with certain findings for improvement of desirable personality traits of marine engineers.

Re-engineering and Re-defining University Libraries in the context of modern Information and Communication Technologies: a study with special reference to the University Libraries in Kerala

Information and communication technologies are the tools that underpin the emerging “Knowledge Society”. Exchange of information or knowledge between people and through networks of people has always taken place. But the ICT has radically changed the magnitude of this exchange, and thus factors such as timeliness of information and information dissemination patterns have become more important than ever.Since information and knowledge are so vital for the all round human development, libraries and institutions that manage these resources are indeed invaluable. So, the Library and Information Centres have a key role in the acquisition, processing, preservation and dissemination of information and knowledge. ln the modern context, library is providing service based on different types of documents such as manuscripts, printed, digital, etc. At the same time, acquisition, access, process, service etc. of these resources have become complicated now than ever before. The lCT made instrumental to extend libraries beyond the physical walls of a building and providing assistance in navigating and analyzing tremendous amounts of knowledge with a variety of digital tools. Thus, modern libraries are increasingly being re-defined as places to get unrestricted access to information in many formats and from many sources.The research was conducted in the university libraries in Kerala State, India. lt was identified that even though the information resources are flooding world over and several technologies have emerged to manage the situation for providing effective services to its clientele, most of the university libraries in Kerala were unable to exploit these technologies at maximum level. Though the libraries have automated many of their functions, wide gap prevails between the possible services and provided services. There are many good examples world over in the application of lCTs in libraries for the maximization of services and many such libraries have adopted the principles of reengineering and re-defining as a management strategy. Hence this study was targeted to look into how effectively adopted the modern lCTs in our libraries for maximizing the efficiency of operations and services and whether the principles of re-engineering and- redefining can be applied towards this.Data‘ was collected from library users, viz; student as well as faculty users; library ,professionals and university librarians, using structured questionnaires. This has been .supplemented by-observation of working of the libraries, discussions and interviews with the different types of users and staff, review of literature, etc. Personal observation of the organization set up, management practices, functions, facilities, resources, utilization of information resources and facilities by the users, etc. of the university libraries in Kerala have been made. Statistical techniques like percentage, mean, weighted mean, standard deviation, correlation, trend analysis, etc. have been used to analyse data.All the libraries could exploit only a very few possibilities of modern lCTs and hence they could not achieve effective Universal Bibliographic Control and desired efficiency and effectiveness in services. Because of this, the users as well as professionals are dissatisfied. Functional effectiveness in acquisition, access and process of information resources in various formats, development and maintenance of OPAC and WebOPAC, digital document delivery to remote users, Web based clearing of library counter services and resources, development of full-text databases, digital libraries and institutional repositories, consortia based operations for e-journals and databases, user education and information literacy, professional development with stress on lCTs, network administration and website maintenance, marketing of information, etc. are major areas need special attention to improve the situation. Finance, knowledge level on ICTs among library staff, professional dynamism and leadership, vision and support of the administrators and policy makers, prevailing educational set up and social environment in the state, etc. are some of the major hurdles in reaping the maximum possibilities of lCTs by the university libraries in Kerala. The principles of Business Process Re-engineering are found suitable to effectively apply to re-structure and redefine the operations and service system of the libraries. Most of the conventional departments or divisions prevailing in the university libraries were functioning as watertight compartments and their existing management system was more rigid to adopt the principles of change management. Hence, a thorough re-structuring of the divisions was indicated. Consortia based activities and pooling and sharing of information resources was advocated to meet the varied needs of the users in the main campuses and off campuses of the universities, affiliated colleges and remote stations. A uniform staff policy similar to that prevailing in CSIR, DRDO, ISRO, etc. has been proposed by the study not only in the university libraries in kerala but for the entire country.Restructuring of Lis education,integrated and Planned development of school,college,research and public library systems,etc.were also justified for reaping maximum benefits of the modern ICTs.

Service quality and reliability assessment of mobile communication infrastructure

The service quality of any sector has two major aspects namely technical and functional. Technical quality can be attained by maintaining technical specification as decided by the organization. Functional quality refers to the manner which service is delivered to customer which can be assessed by the customer feed backs. A field survey was conducted based on the management tool SERVQUAL, by designing 28 constructs under 7 dimensions of service quality. Stratified sampling techniques were used to get 336 valid responses and the gap scores of expectations and perceptions are analyzed using statistical techniques to identify the weakest dimension. To assess the technical aspects of availability six months live outage data of base transceiver were collected. The statistical and exploratory techniques were used to model the network performance. The failure patterns have been modeled in competing risk models and probability distribution of service outage and restorations were parameterized. Since the availability of network is a function of the reliability and maintainability of the network elements, any service provider who wishes to keep up their service level agreements on availability should be aware of the variability of these elements and its effects on interactions. The availability variations were studied by designing a discrete time event simulation model with probabilistic input parameters. The probabilistic distribution parameters arrived from live data analysis was used to design experiments to define the availability domain of the network under consideration. The availability domain can be used as a reference for planning and implementing maintenance activities. A new metric is proposed which incorporates a consistency index along with key service parameters that can be used to compare the performance of different service providers. The developed tool can be used for reliability analysis of mobile communication systems and assumes greater significance in the wake of mobile portability facility. It is also possible to have a relative measure of the effectiveness of different service providers.

Discrete Time Inventory Models with/without Positive Service Time

In everyday life different flows of customers to avail some service facility or other at some service station are experienced. In some of these situations, congestion of items arriving for service, because an item cannot be serviced Immediately on arrival, is unavoidable. A queuing system can be described as customers arriving for service, waiting for service if it is not immediate, and if having waited for service, leaving the system after being served. Examples Include shoppers waiting in front of checkout stands in a supermarket, Programs waiting to be processed by a digital computer, ships in the harbor Waiting to be unloaded, persons waiting at railway booking office etc. A queuing system is specified completely by the following characteristics: input or arrival pattern, service pattern, number of service channels, System capacity, queue discipline and number of service stages. The ultimate objective of solving queuing models is to determine the characteristics that measure the performance of the system