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.

Reduced L_1 level width and Coster-Kronig yields by relaxation and continuum interactions in atomic zinc

Calculations of the level width \gamma( L_1) and the f_12 and f_13 Coster-Kronig yields for atomic zinc have been performed with Dirac-Fock wave functions. For \gamma(L_1), a large deviation between theory and evaluated data exists. We include the incomplete orthogonality of the electron orbitals as well as the interchannel interaction of the decaying states. Orbital relaxation reduces the total rates in all groups of the electron-emission spectrum by about 10-20 %. Different, however, is the effect of the continuum interaction. The L_1-L_23X Coster-Kronig part of the spectrum is definitely reduced in its intensity, whereas the MM and MN spectra are slightly enhanced. This results in a reduction of Coster-Kronig yields, where for medium and heavy elements considerable discrepancies have been found in comparison to relativistic theory. Briefly, we discuss the consequences of our calculations for heavier elements.

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.

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

Prevalencia de los trastornos de voz ocupacionales en los docentes de dos instituciones educativas de nivel superior en Colombia en el año 2013-2014

Resumen: En la población docente, el uso de la voz como principal herramienta del trabajo por su esfuerzo constante y prolongado constituye el principal factor de riesgo para padecer trastornos de la voz, concomitante con otros factores que inciden en la presentación de estas patologías. Objetivo: Determinar la prevalencia de los trastornos en la voz y sus factores asociados de la población docente de dos instituciones de educación superior (IES) en Colombia y los factores de riesgo asociados. Materiales y métodos: Se realizó un estudio descriptivo de tipo transversal, en el que participaron 149 docentes de dos IES (instituciones de educación superior) de dos ciudades de Colombia. Se aplicó un cuestionario sustentado en el Modelo de Técnicas Foniátricas para Prevenir la Disfonía en Profesores de Secundaria en Portugal y validado por la escuela de Medicina y Ciencias de la Salud, programa de fonoaudiología de la Universidad del Rosario con el trabajo denominado “La Voz como herramienta de trabajo” para Colombia; el cual indagaba los factores riesgo asociados al uso de la voz en el quehacer docente. Se realizó un análisis descriptivo de las variables cualitativas con frecuencias absolutas y porcentajes, medidas de tendencia central, promedio y mediana, de dispersión y desviación estándar. La información recolectada fue analizada con el software SPSS.PASW 18. La correlación entre las variables dependientes y las independientes, se realizaron con el coeficiente no-paramétrico de Spearman y la asociación con la prueba Ji-cuadrado de Pearson o el test exacto de Fisher (valores esperados < 5). Se evaluaron las distribuciones de las variables ordinales de las variables de problemas de la voz con el género, con la prueba no-paramétrica exacta de Mann Whitney. Las pruebas estadísticas se evaluaron a un nivel de significancia del 5% (p<0.05). Resultados: El promedio de edad fue de 36±11.7 años, con un rango que varió entre 25 y 68 años. El género más frecuente fue el masculino con 57,0% de participación. Los datos presentados se dan como resultado de las respuestas a tres preguntas indicativas de los trastornos de voz, las cuales no fueron respondidas por la totalidad de los docentes, por esta razón los datos se presentan así t= número total de personas que respondieron la pregunta y n= número de personas que respondieron afirmativamente. La prevalencia de alteración de voz fue del 63,4% (t=82; n=52), de disminución en el volumen de su voz de 57,3% (t=122; n=70) y cansancio laríngeo en el 76,8% (t=121; n=93). El cansancio laríngeo fue significativamente mayor en los hombres que en las mujeres (p=0.026, Test Mann Whitney exacto a una cola), con algunos hábitos de voz como el realizar esfuerzos en el cuello al hablar (rs = 0,461; p< 0,001) y con la dificultad para inhalar o exhalar aire al hablar (rs = 0,368; p<0.001), con el ruido de fondo (rs =0,361, p<0,001), al permanecer en ambientes contaminados con polvo y humedad (rs=0,311; p=0.001), con sufrir de estrés representado por dolor cervical en espalda y hombros (rs=0,349, p<0.001), y con los problemas familiares (rs= 0,397; p<0.001). Al analizar con la disminución del volumen de voz durante la práctica docente, las correlaciones más significativas mostradas fue estadísticamente mayor entre los hombres que en las mujeres (p=0.006, Test Mann Whitney exacto a una cola), con el esfuerzo cervical para hablar (rs =:0,596, p=<,001), y con el presentar dificultad para inhalar/exhalar aire al usar la voz (rs =0,508, p<,001), con la exposición a ruido de fondo (rs=0,204, p=0,030), ambientes contaminados con polvo y humedad (rs:=305, p<,001), con el estrés (rs =0,316, p=0,001), con los problemas familiares (rs =0,560, p<,001) y en las mujeres con la alteración de la voz en presencia de la menstruación (rs =0,751, p=0,000). Por último, se correlacionó con las alteraciones de voz durante la exposición laboral en la que se mostró mayor correlación en las mujeres que en los hombres (p=0.001, Test Mann Whitney exacto a una cola). Se mostró correlación directa con el no realizar pausas al hablar (rs=0,337, p<0,001), con toser para aclarar la voz (rs =0,349, p=0,001), y con el uso de la voz grave (rs =0,975; p=,004) ,con la presencia de ruido de fondo mientras se dicta clase (rs =0,370, p=0,001) con el permanecer en ambientes contaminados con polvo y humedad (rs =0,253,p=,023), con los síntomas cervicales asociados al estrés (rs=0,323, p=0,003), e inversa con los cambios en tono y volumen de la voz en presencia de menstruación en las mujeres (rs=-0,414,p=,017). Conclusiones: Con los hallazgos encontrados en este estudio es importante reconocer que en las características demográficas, se encontró que el género masculino refirió mayor cantidad de problemas de voz. Para las características laborales la antigüedad ocupacional es factor principal que incide en los problemas de voz; en el análisis de las características demográfico– laborales en las variables analizadas, el grupo etario que reporto cansancio laríngeo se encontraba entre los 36 a 45 años de edad, y los que referían un tiempo de exposición ocupacional mayor a 6 y menor a 15 años. En cuanto a los factores ambientales se identificó que la asociación más significativa está relacionada con estar sometido a cambios bruscos de temperatura, estar expuesto a ruido de fondo durante su labor y finalmente a permanecer en ambientes contaminados. Por ultimo al analizar las alteraciones de la voz con las características personales de los docentes, se observó que el estrés y los problemas familiares inciden de forma significativa en estas patologías. Con estos resultados se recomienda establecer un sistema de vigilancia epidemiológica en las IES, donde se capacite integralmente a los docentes en cuanto a los factores de riesgo personales y de hábitos de voz, además de supervisar y adecuar los factores ambientales que inciden en la presentación de trastornos de voz para evitar la presentación de estas patologías.

Enhanced convolution approach for CAC in ATM networks, an analytical study and implementation

The characteristics of service independence and flexibility of ATM networks make the control problems of such networks very critical. One of the main challenges in ATM networks is to design traffic control mechanisms that enable both economically efficient use of the network resources and desired quality of service to higher layer applications. Window flow control mechanisms of traditional packet switched networks are not well suited to real time services, at the speeds envisaged for the future networks. In this work, the utilisation of the Probability of Congestion (PC) as a bandwidth decision parameter is presented. The validity of PC utilisation is compared with QOS parameters in buffer-less environments when only the cell loss ratio (CLR) parameter is relevant. The convolution algorithm is a good solution for CAC in ATM networks with small buffers. If the source characteristics are known, the actual CLR can be very well estimated. Furthermore, this estimation is always conservative, allowing the retention of the network performance guarantees. Several experiments have been carried out and investigated to explain the deviation between the proposed method and the simulation. Time parameters for burst length and different buffer sizes have been considered. Experiments to confine the limits of the burst length with respect to the buffer size conclude that a minimum buffer size is necessary to achieve adequate cell contention. Note that propagation delay is a no dismiss limit for long distance and interactive communications, then small buffer must be used in order to minimise delay. Under previous premises, the convolution approach is the most accurate method used in bandwidth allocation. This method gives enough accuracy in both homogeneous and heterogeneous networks. But, the convolution approach has a considerable computation cost and a high number of accumulated calculations. To overcome this drawbacks, a new method of evaluation is analysed: the Enhanced Convolution Approach (ECA). In ECA, traffic is grouped in classes of identical parameters. By using the multinomial distribution function instead of the formula-based convolution, a partial state corresponding to each class of traffic is obtained. Finally, the global state probabilities are evaluated by multi-convolution of the partial results. This method avoids accumulated calculations and saves storage requirements, specially in complex scenarios. Sorting is the dominant factor for the formula-based convolution, whereas cost evaluation is the dominant factor for the enhanced convolution. A set of cut-off mechanisms are introduced to reduce the complexity of the ECA evaluation. The ECA also computes the CLR for each j-class of traffic (CLRj), an expression for the CLRj evaluation is also presented. We can conclude that by combining the ECA method with cut-off mechanisms, utilisation of ECA in real-time CAC environments as a single level scheme is always possible.

Understanding projections of sea level rise in a Hadley Centre coupled climate model

Sea level changes resulting from CO2-induced climate changes in ocean density and circulation have been investigated in a series of idealised experiments with the Hadley Centre HadCM3 AOGCM. Changes in the mass of the ocean were not included. In the global mean, salinity changes have a negligible effect compared with the thermal expansion of the ocean. Regionally, sea level changes are projected to deviate greatly from the global mean (standard deviation is 40% of the mean). Changes in surface fluxes of heat, freshwater and wind stress are all found to produce significant and distinct regional sea level changes, wind stress changes being the most important and the cause of several pronounced local features, while heat and freshwater flux changes affect large parts of the North Atlantic and Southern Ocean. Regional change is related mainly to density changes, with a relatively small contribution in mid and high latitudes from change in the barotropic circulation. Regional density change has an important contribution from redistribution of ocean heat content. In general, unlike in the global mean, the regional pattern of sea level change due to density change appears to be influenced almost as much by salinity changes as by temperature changes, often in opposition. Such compensation is particularly marked in the North Atlantic, where it is consistent with recent observed changes. We suggest that density compensation is not a property of climate change specifically, but a general behavior of the ocean.

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.

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.

A micro-level simulation for the prediction of intention and behaviour

In this contribution we aim at anchoring Agent-Based Modeling (ABM) simulations in actual models of human psychology. More specifically, we apply unidirectional ABM to social psychological models using low level agents (i.e., intra-individual) to examine whether they generate better predictions, in comparison to standard statistical approaches, concerning the intentions of performing a behavior and the behavior. Moreover, this contribution tests to what extent the predictive validity of models of attitude such as the Theory of Planned Behavior (TPB) or Model of Goal-directed Behavior (MGB) depends on the assumption that peoples’ decisions and actions are purely rational. Simulations were therefore run by considering different deviations from rationality of the agents with a trembling hand method. Two data sets concerning respectively the consumption of soft drinks and physical activity were used. Three key findings emerged from the simulations. First, compared to standard statistical approach the agent-based simulation generally improves the prediction of behavior from intention. Second, the improvement in prediction is inversely proportional to the complexity of the underlying theoretical model. Finally, the introduction of varying degrees of deviation from rationality in agents’ behavior can lead to an improvement in the goodness of fit of the simulations. By demonstrating the potential of ABM as a complementary perspective to evaluating social psychological models, this contribution underlines the necessity of better defining agents in terms of psychological processes before examining higher levels such as the interactions between individuals.

Service oriented approach to facility management using extended building information modelling

Facility management (FM), from a service oriented approach, addresses the functions and requirements of different services such as energy management, space planning and security service. Different service requires different information to meet the needs arising from the service. Object-based Building Information Modelling (BIM) is limited to support FM services; though this technology is able to generate 3D models that semantically represent facility’s information dynamically over the lifecycle of a building. This paper presents a semiotics-inspired framework to extend BIM from a service-oriented perspective. The extended BIM, which specifies FM services and required information, will be able to express building service information in the right format for the right purposes. The service oriented approach concerns pragmatic aspect of building’s information beyond semantic level. The pragmatics defines and provides context for utilisation of building’s information. Semiotics theory adopted in this paper is to address pragmatic issues of utilisation of BIM for FM services.

Knowledge dissemination in the global service marketing community

Purpose– The evolution of the service marketing field was marked by the emergence of a global, vigorous and tolerant community of service marketing researchers. This paper seeks to examine the history of the service marketing community and argues that it may be an archetype for building the emergent global service research community. Design/methodology/approach– The study combines qualitative and quantitative approaches. The authors interviewed four pioneering service scholars and also collected descriptive data (e.g. Authorship, Affiliation, Title, Keywords) of all service related articles published in 13 top peer‐reviewed marketing and service journals over the last 30 years (5,432 articles; 6,450 authors). In a dynamic analysis the authors mapped global collaboration between countries over time and detected clusters of international collaboration. Findings– Findings suggest a growing international collaboration for the USA and the UK, while for other countries like Israel the global collaboration started from a high level and decreases now. Further, the service marketing community never became polarized and there were always contributions from researchers all over the world. Research limitations/implications– As the global service research community is developing, service marketing becomes a research neighborhood within the broader service research community. Simultaneously, other research neighborhoods are emerging within this new community (e.g. service arts, service management, service engineering, service science). Originality/value– Anchored on the social evolution and biological evolution metaphors, this study explains the evolution of the service marketing field from both qualitative and quantitative perspectives. Furthermore, it explains the development of the service marketing community as an archetype for building the global service research community.

The brand likeability scale: an exploratory study of likeability in firm-level brands

We develop a new measurement scale to assess consumers’ brand likeability in firm-level brands. We present brand likeability as a multidimensional construct. In the context of service experience purchases, we find that increased likeability in brands results in: (1) greater amount of positive association; (2) increased interaction interest; (3) more personified quality; and (4) increased brand contentment. The four-dimensional multiple-item scale demonstrates good psychometric properties, showing strong evidence of reliability as well as convergent, discriminant and nomological validity. Our findings reveal that brand likeability is positively associated with satisfaction and positive word of mouth. The scale extends existing branding research, providing brand managers with a metric so that likeability can be managed strategically. It addresses the need for firms to act more likeably in an interaction-dominated economy. Focusing on likeability acts as a differentiator and encourages likeable brand personality traits. We present theoretical implications and future research directions on the holistic brand likeability concept.