Stochastic Inventory with/without Service Time, Reneging and Retrial of Customers

This thesis Entitled Stochastic modelling and analysis.This thesis is divided into six chapters including this introductory chapter. In second chapter, we consider an (s,S) inventory model with service, reneging of customers and finite shortage of items.In the third chapter, we consider an (s,S) inventoiy system with retrial of customers. Arrival of customers forms a Poisson process with rate. When the inventory level depletes to s due to demands, an order for replenishment is placed.In Chapter 4, we analyze and compare three (s,S) inventory systems with positive service time and retrial of customers. In all these systems, arrivals of customers form a Poisson process and service times are exponentially distributed. In chapter 5, we analyze and compare three production inventory systems with positive service time and retrial of customers. In all these systems, arrivals of customers form a Poisson process and service times are exponentially distributed.In chapter 6, we consider a PH /PH /l inventory model with reneging of customers and finite shortage of items.

Investigations on Stochastic Storage Systems with Positive Service Time

In this thesis the queueing-inventory models considered are analyzed as continuous time Markov chains in which we use the tools such as matrix analytic methods. We obtain the steady-state distributions of various queueing-inventory models in product form under the assumption that no customer joins the system when the inventory level is zero. This is despite the strong correlation between the number of customers joining the system and the inventory level during lead time. The resulting quasi-birth-anddeath (QBD) processes are solved explicitly by matrix geometric methods

Studies on Inventory with Positive Service Time Under Local Purchase Driven by N/T- Policy

In this thesis, certain continuous time inventory problems with positive service time under local purchase guided by N/T-policy are analysed. In most of the cases analysed, we arrive at stochastic decomposition of system states, that is, the joint distribution of the system states is obtained as the product of marginal distributions of the components. The thesis is divided into ve chapters

Influence of Frequent Flyer Programme and Airline Service Quality on Re-buy Intentions of Airline Frequent Passengers

The growth potential of service sector, especially the aviation sector in the Indian economy is splendid. Therefore, it is crucial for the airline service providers to realize their customers, design offers and deliver the desired value to their customers. This study reveals the effect of airline passenger satisfactions particularly on re-buy intentions derived from the attributes-level performance dimensions of both service aspects and loyalty programme of an airline. The mediation effect of satisfaction and other selected antecedents on the re-buy intention of a passenger is hypothesized in this study. Critical areas affecting buying intentions such as core service quality and loyalty attribute-level performances, effect of frequent flyer programme and service quality satisfaction, passenger trust on airline, brand image and moderating effects of perceived value, frequent programme status and travel frequency of airline passengers are linked in a structural model to assess the strength of each facet in affecting re-buy intentions. Implications to the airlines were made based on the finding that re-buy intentions cannot be attributed solely to the impacts of frequent flyer programme, rather affected through the mediation effect of airline service quality satisfaction, which is very much valid for the higher FFP status category of frequent travelers. The effects of moderation caused by perceived value, FFP status and flying experience were also found to be significant in making re-buy intentions.

Influence of farmers educational level on comprehending, acting-upon and sharing of agro advisories

Although short messaging service (SMS) through mobile phones has quickly gained popularity among most other sectors in India, its potential is not fully realised in the agriculture sector as a cost effective service to reach farmers and elicit desirable action. Despite the cost effectiveness, mobile messaging has remained a challenge in the farming sector in terms of its end use and action as far as extension systems are concerned. While there could be many influencing factors affecting the utility of mobile messages, this study assumed that educational level of farmers could be a major factor. A telephone survey was conducted to ascertain the influence of farmers’ education on the level of utilisation of mobile-based advisories. Farmers with higher education level showed better comprehension of advisories, actedupon the advisories more promptly and shared the information with fellow farmers more often than those with lower education level. There was a significant association between comprehending, sharing and acting upon advisories. This has implications to achieve enhanced extension reach with higher efficiency in terms of cost and time.

Evaluación de la psicopatología del preescolar mediante el Early Childhood Inventory-4 (ECI-4): concordancia entre padres y maestros.= Assessment of psychopathology in preschool age children through the Early Childhood Inventory-4 (ECI-4): Agreement among parents and teachers

El objetivo principal de este estudio es conocer la concordancia entre informantes, padres y maestros, en cada una de las dimensiones o categorías diagnósticas del Early Childhood Inventory-4 (ECI-4). Además, se pretende analizar la influencia de la presencia de problemas de salud en los padres en la descripción y valoración de la conducta de una muestra de 204 alumnos de preescolar (3 a 6 años) de perfiles socioeconómicos diferentes. Los resultados indican que los padres tienden a valorar con mayor severidad los síntomas, observándose una mayor concordancia entre informantes en los relativos a los trastornos del desarrollo

Enhanced multi-layer protection in multi-service GMPLS networks

This paper focuses on QoS routing with protection in an MPLS network over an optical layer. In this multi-layer scenario each layer deploys its own fault management methods. A partially protected optical layer is proposed and the rest of the network is protected at the MPLS layer. New protection schemes that avoid protection duplications are proposed. Moreover, this paper also introduces a new traffic classification based on the level of reliability. The failure impact is evaluated in terms of recovery time depending on the traffic class. The proposed schemes also include a novel variation of minimum interference routing and shared segment backup computation. A complete set of experiments proves that the proposed schemes are more efficient as compared to the previous ones, in terms of resources used to protect the network, failure impact and the request rejection ratio

Análisis de la competitividad del sub sector lechero de los pequeños y medianos productores frente al TLC con la Unión Europea

A través de los años y en busca de ser partícipes del fenómeno de la globalización y de la integración económica entre países, Colombia ha buscado establecer acuerdos comerciales estratégicamente adecuados para transformar la economía interna, expandirse a nivel internacional e intercambiar productos en los que no se es especializado. Ante esto, Colombia firmó el Tratado de Libre Comercio con la Unión Europea en Junio del 2012, que entró en vigencia en Agosto del 2013, y hasta el momento la situación del sector lechero ha sido crítica, pues carece del nivel de competitividad suficiente para garantizar la perdurabilidad de los pequeños y medianos productores de leche. El diagnóstico del sector lechero colombiano permite tener una visión más clara sobre las principales características de los sistemas de producción del país, es aquí donde se conocen las falencias que se presentan en el sector, pues la productividad es baja, los costos de producción son altos y los precios tienen una tendencia al alza, colocando a los productos nacionales en desventaja frente a la gran oferta internacional que invade el mercado interno con precios reducidos y con mejor calidad. Además, se identifica también que gran parte de los productores de leche son informales y por lo tanto es difícil consolidar la información referente al sector y convertirla en conocimiento para efectuar planes de cambio y transformación para mejorar la situación. Del lado contrario y actuando como principal competidor en este caso de estudio, se encuentra la Unión Europea. Su diagnóstico ubica esta zona geográfica en una posición indudablemente privilegiada: precios bajos, mejor calidad, alta productividad, entre otras características que hacen de la UE una verdadera amenaza para los pequeños y medianos productores colombianos. La sobreproducción que se presencia en esta asociación económica y política crea la necesidad de explorar otros mercados para poner a disposición dicha producción, y el Tratado de Libre Comercio con Colombia es una opción para compensar esa oferta con una demanda insatisfecha. Con el fin de conocer profundamente las implicaciones del TLC con la Unión Europea y cómo afecta este acuerdo a los pequeños y medianos productores de leche en Colombia, fue necesario abordar algunos puntos clave en la negociación establecida y a partir de estos determinar si este tratado es realmente una oportunidad para el campesino informal que se dedica a la producción de leche para el autoconsumo y/o la comercialización en veredas y pueblos, o por el contrario, es una plataforma que afecta negativamente a las 450 mil familias que viven de este oficio y que no tienen los niveles de competitividad exigidos para enfrentar una competencia extranjera tan fuerte como lo es la Unión Europea. Por último, el análisis DOFA permite crear estrategias coherentes y viables relacionando las fortalezas y debilidades de Colombia con las oportunidades y amenazas que implica tener un acuerdo de libre comercio con la Unión Europea. Estas estrategias contribuyen a mejorar la competitividad del sector en busca de garantizar una mayor perdurabilidad de los pequeños y medianos productores de leche, y de esta manera se logrará no sólo aprovechar este acuerdo comercial, si no también conquistar otros mercados internacionales con un producto de mejor calidad.

Engagement y productividad en las empresas

El presente trabajo pretende mostrar algunos avances en el término “engagement”, y como puede ser implementado en las organizaciones, teniendo en cuenta los diferentes factores que intervienen, para que los trabajadores se sientan “engaged” dentro de la organización. Además busca relacionar las diferentes habilidades y tipos de liderazgo que los altos mandos utilizan con sus empleados y como éste afecta la productividad de los trabajadores en las organizaciones. Para esto, se realizó una investigación de las clases de liderazgo y los comportamientos de los altos mandos, que pueden afectar positiva y negativamente el vínculo y sentido de pertenencia que tienen los trabajadores con la empresa en la que trabajan. Considerando importante las habilidades del liderazgo transformacional, para lograr desarrollar algún grado de engagement en los trabajadores, lo cual genera a su vez, un alza en la productividad de sus resultados dentro de la organización.

Indicadores da individualização de cuidados para o curso de licenciatura em enfermagem

RESUMO: A individualização dos cuidados de enfermagem tem sido associada a uma evolução clínica mais favorável, representando um importante parâmetro de avaliação e de desenvolvimento dos serviços de saúde. A tónica atribuída a esta problemática não só é evidenciada por diversos autores, como se enquadra nas metas de modernização do Sistema Nacional de Saúde e é destaque em vários códigos normativos da profissão nacionais e internacionais, como uma obrigação moral e deontológica. Assim, pretende-se mediante os ganhos em saúde sensíveis às intervenções de enfermagem, identificar quais indicadores do cuidado individualizado, para se efectivar a sua incorporação na formação inicial em enfermagem. Para tal efeito, construiu-se uma bateria de indicadores mediante análise de duas revisões sistemáticas da literatura, que teve por base o Modelo da Eficácia do Papel de Enfermagem, desenvolvido por Irvine et al. (1998). Para à adaptação à realidade portuguesa recorreu-se à técnica de Delphi, com duas rondas, que incluiu respectivamente, 12 e 10 peritos de enfermagem. Na análise de dados utilizou-se o nível de concordância superior ou igual a 90%, na última ronda. Na segunda fase do estudo, aplicou-se um inquérito por questionário (α de Cronbach = 0,919) para testar a sua aplicabilidade dos indicadores, a 156 enfermeiros, do mesmo hospital da área da grande Lisboa, no Serviço de Medicina e Cirurgia. Recorreu-se ao SPSS, versão 19 e realizou-se análise univariada e estatística analítica. Na bateria final de indicadores foram incorporados aqueles com ponderação positiva (≥51%). Os dados qualitativos obtidos foram submetidos a análise de conteúdo. Dos 58 indicadores iniciais, consolidaram-se 8 categorias: cuidado à pessoa em fim de vida e família, toque terapêutico, educação para a auto-gestão da saúde, cuidados de proximidade, gestão de casos, empoderamento/ literacia para a saúde, linha telefónica de apoio permanente/ tele-assistência e apoio psico-emocional, com valorização de 28 indicadores. O tempo de experiência profissional, tipo de serviço e tempo de permanência no mesmo serviço influenciou a percepção dos enfermeiros, confirmando os pressupostos de Irvine et al. (1998) e Benner (2001). A correlação total dos indicadores, no questionário, variou entre 0,248 e 0,650, para p<0,01. O facto de todas as correlações serem positivas significa que provavelmente estão associados à problemática da individualização, pelo que se sugere a sua transposição para o ensino de enfermagem. ABSTRACT: The individualization of nursing care has been associated with a more favorable clinical evolution, an important parameter for the evaluation and development of health services. The emphasis given to this problem is not only evidenced by several authors, as fits the goals of modernizing the National Health System and is featured in several normative codes of the profession nationally and internationally, as a moral and ethical obligation. Thus, it is intended by the gains in health sensitive to nursing interventions, identify indicators of individualized care and give effect to its incorporation into the initial training in nursing. For this purpose, we constructed a series of indicators by analyzing two systematic reviews of literature, which was based on the The Nursing Role Effectiveness Model developed by Irvine et al. (1998). For the adaptation to the Portuguese appealed to the Delphi technique with two rounds, which included, respectively, 10 and 12 nursing experts. In data analysis we used the level of agreement greater than or equal to 90% in the last round. In the second phase of the study, we applied a questionnaire (Cronbach's α = 0.919) to test the applicability of the indicators, the 156 nurses in the same hospital in the Greater Lisbon area, the Department of Medicine and Surgery. Done using the SPSS, version 19 and conducted a univariate analysis and analytical statistics. In the final heat of indicators were incorporated into those with positive weight (≥ 51%). Qualitative data were subjected to content analysis. Of the initial 58 indicators, eight were consolidated categories: care to the person and family life, therapeutic touch education for self-management of health care outreach, case management, empowerment / literacy to health, a telephone line permanent support / tele-assistance and psycho-emotional, with an appreciation of 28 indicators. The length of professional experience, type of service and length of stay in the same service influenced the perception of nurses, confirming the assumptions of Irvine et al. (1998) and Benner (2001). The total correlation of the indicators in the questionnaire ranged between 0.248 and 0.650, p <0.01. The fact that all correlations are positive means that are probably associated with the problem of individuation, which is suggested by its implementation in nursing education.

Uptake of a free coronary heart disease risk screening programme in community pharmacy: the Healthy Heart Assessment service

Introduction Health promotion (HP) aims to enhance good health while preventing ill-health at three levels of activity; primary (preventative), secondary (diagnostic) and tertiary (management).1 It can range from simple provision of health education to ongoing support, but the effectiveness of HP is ultimately dependent on its ability to influence change. HP as part of the Community Pharmacy Contract (CPC) aims to increase public knowledge and target ‘hard-to-reach’ individuals by focusing mainly on primary and tertiary HP. The CPC does not include screening programmes (secondary HP) as a service. Coronary heart disease (CHD) is a significant cause of morbidity and mortality in the UK. While there is evidence to support the effectiveness of some community pharmacy HP strategies in CHD, there is paucity of research in relation to screening services.2 Against this background, Alliance Pharmacy introduced a free CHD risk screening programme to provide tailored HP advice as part of a participant–pharmacist consultation. The aim of this study is to report on the CHD risk levels of participants and to provide a qualitative indication of consultation outcomes. Methods Case records for 12 733 people who accessed a free CHD risk screening service between August 2004 and April 2006 offered at 217 community pharmacies were obtained. The service involved initial self-completion of the Healthy Heart Assessment (HHA) form and measurement of height, weight, body mass index, blood pressure, total cholesterol and highdensity lipoprotein levels by pharmacists to calculate CHD risk.3 Action taken by pharmacists (lifestyle advice, statin recommendation or general practitioner (GP) referral) and qualitative statements of advice were recorded, and a copy provided to the participants. The service did not include follow-up of participants. All participants consented to taking part in evaluations of the service. Ethical committee scrutiny was not required for this service development evaluation. Results Case records for 10 035 participants (3658 male) were evaluable; 5730 (57%) were at low CHD risk (<15%); 3636 (36%) at moderate-to-high CHD risk (≥15%); and 669 (7%) had existing heart disease. A significantly higher proportion of male (48% versus 30% female) participants were at moderate- to-high risk of CHD (chi-square test; P < 0.005). A range of outcomes resulted from consultations. Lifestyle advice was provided irrespective of participants’ CHD risk or existing disease. In the moderate-to-high-risk group, of which 52% received prescribed medication, lifestyle advice was recorded for 62%, 16% were referred and 34% were advised to have a re-assessment. Statin recommendations were made in 1% of all cases. There was evidence of supportive and motivational statements in the advice recorded. Discussion Pharmacists were able to identify individuals’ level of CHD risk and provide them with bespoke advice. Identification of at-risk participants did not automatically result in referrals or statin recommendation. One-third of those accessing the screening service had moderate-to-high risk of CHD, a significantly higher proportion of whom were men. It is not known whether these individuals had been previously exposed to HP but presumably by accessing this service they may have contemplated change. As effectiveness of HP advice will depend among other factors on ability to influence change, future consultations may need to explore patients’ attitude towards change in relation to the Trans Theoretical Model4 to better tailor HP advice. The high uptake of the service by those at moderate-to-high CHD risk indicates a need for this type of screening programme in community pharmacy, perhaps specifically to reach men who access medical services less.

The relationships of age and length of service with job satisfaction: an examination of hotel employees in Thailand

Earlier studies suggest age is positively associated with job satisfaction, while others use length of service, or tenure, as a predictor of job satisfaction levels. This article examines whether age and tenure are individual determinants of satisfaction, or whether there is an interaction between the two. The results indicate that employee age is not significantly associated with overall job satisfaction level, but that tenure is. There is also significant relationship between tenure and facets of satisfaction (job, pay and fringe benefits), but the effect of tenure on satisfaction is significantly modified by age.

Understanding construction consortia: Theory, practice and opinions

Firms form consortia in order to win contracts. Once a project has been awarded to a consortium each member then concentrates on his or her own contract with the client. Therefore, consortia are marketing devices, which present the impression of teamworking, but the production process is just as fragmented as under conventional procurement methods. In this way, the consortium forms a barrier between the client and the actual construction production process. Firms form consortia, not as a simple development of normal ways of working, but because the circumstances for specific projects make it a necessary vehicle. These circumstances include projects that are too large or too complex to undertake alone or projects that require on-going services which cannot be provided by the individual firms inhouse. It is not a preferred way of working, because participants carry extra risk in the form of liability for the actions of their partners in the consortium. The behaviour of members of consortia is determined by their relative power, based on several factors, including financial commitment and ease of replacement. The level of supply chain visibility to the public sector client and to the industry is reduced by the existence of a consortium because the consortium forms an additional obstacle between the client and the firms undertaking the actual construction work. Supply chain visibility matters to the client who otherwise loses control over the process of construction or service provision, while remaining accountable for cost overruns. To overcome this separation there is a convincing argument in favour of adopting the approach put forward in the Project Partnering Contract 2000 (PPC2000) Agreement. Members of consortia do not necessarily go on to work in the same consortia again because members need to respond flexibly to opportunities as and when they arise. Decision-making processes within consortia tend to be on an ad hoc basis. Construction risk is taken by the contractor and the construction supply chain but the reputational risk is carried by all the firms associated with a consortium. There is a wide variation in the manner that consortia are formed, determined by the individual circumstances of each project; its requirements, size and complexity, and the attitude of individual project leaders. However, there are a number of close working relationships based on generic models of consortia-like arrangements for the purpose of building production, such as the Housing Corporation Guidance Notes and the PPC2000.

In-service and pre-service teachers' opinion on the use of models in teaching chemistry

The presented study examined the opinion of in-service and prospective chemistry teachers about the importance of usage of molecular and crystal models in secondary-level school practice, and investigated some of the reasons for their (non-) usage. The majority of participants stated that the use of models plays an important role in chemistry education and that they would use them more often if the circumstances were more favourable. Many teachers claimed that three-dimensional (3d) models are still not available in sufficient number at their schools; they also pointed to the lack of available computer facilities during chemistry lessons. The research revealed that, besides the inadequate material circumstances, less than one third of participants are able to use simple (freeware) computer programs for drawing molecular structures and their presentation in virtual space; however both groups of teachers expressed the willingness to improve their knowledge in the subject area. The investigation points to several actions which could be undertaken to improve the current situation.

Comparison of results from several AOGCMs for global and regional sea-level change 1900-2100

Sea-level rise is an important aspect of climate change because of its impact on society and ecosystems. Here we present an intercomparison of results from ten coupled atmosphere-ocean general circulation models (AOGCMs) for sea-level changes simulated for the twentieth century and projected to occur during the twenty first century in experiments following scenario IS92a for greenhouse gases and sulphate aerosols. The model results suggest that the rate of sea-level rise due to thermal expansion of sea water has increased during the twentieth century, but the small set of tide gauges with long records might not be adequate to detect this acceleration. The rate of sea-level rise due to thermal expansion continues to increase throughout the twenty first century, and the projected total is consequently larger than in the twentieth century; for 1990-2090 it amounts to 0.20-0.37 in. This wide range results from systematic uncertainty in modelling of climate change and of heat uptake by the ocean. The AOGCMs agree that sea-level rise is expected to be geographically non-uniform, with some regions experiencing as much as twice the global average, and others practically zero, but they do not agree about the geographical pattern. The lack of agreement indicates that we cannot currently have confidence in projections of local sea- level changes, and reveals a need for detailed analysis and intercomparison in order to understand and reduce the disagreements.