632 resultados para Discharge Service


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Transitions between the two discharge modes in a low-frequency (∼460 kHz) inductively coupled plasma sustained by an internal oscillating radio frequency (rf) current sheet are studied. The unidirectional rf current sheet is generated by an internal antenna comprising two orthogonal sets of synphased rf currents driven in alternately reconnected copper litz wires. It is shown that in the low-to-intermediate pressure range the plasma source can be operated in the electrostatic (E) and electromagnetic (H) discharge modes. The brightness of the E -mode argon plasma glow is found remarkably higher than in inductively coupled plasmas with external flat spiral "pancake" coils. The cyclic variations of the input rf power result in pronounced hysteretic variations of the optical emission intensity and main circuit parameters of the plasma source. Under certain conditions, it appears possible to achieve a spontaneous E→H transition ("self-transition"). The observed phenomenon can be attributed to the thermal drift of the plasma parameters due to the overheating of the working gas. The discharge destabilizing factors due to the gas heating and step-wise ionization are also discussed. © 2005 American Vacuum Society.

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A theoretical model of the plasma discharge in a metal cylinder pumped by an operating gas of an arbitrary nature is presented. The ionization is carried out by the surface wave (SW) propagating along a coaxial metal wire. The model includes the local dispersion relation, the energy balance equation, and the relation between the absorbed power per unit length and the local plasma density. Two typical regimes of the discharge are analyzed. In both regimes the axial and radial profiles of the plasma density of the electromagnetic field components and of the SW intensity are obtained. The possible use of the obtained results in plasma technology are discussed.

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The structure of a microwave gas discharge produced and sustained by a surface wave (SW) propagating along a cylindrical metal antenna with a dielectric coating is studied. The SW that produces and sustains the microwave gas discharge propagates along an external magnetic field and has an eigenfrequency in the range between the electron cyclotron and electron plasma frequencies. The presence of a dielectric (vacuum) sheath region separating the antenna from the plasma is assumed. The spatial distributions of the produced plasma density, electromagnetic fields, energy flow density, phase velocity and reverse skin depth of the SW are obtained analytically and numerically.

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This study adopts the premise that innovation capability underpins a service firm's value creation ability and that management style, employee behaviors and marketing underpin its innovation capability. This study examines the role of managers and employees in the creation and delivery of superior value to customers via the firm's innovation capability. To test this premise the current study examines the role of transformational leadership (TFL) as an aspect of the service firm's management style in creating and delivering value to customers through its services. This study adopts a multi-level study, collecting data from managers, employees and customers of service firms in a Southeast-Asian country, Cambodia. The results show that a service firm's innovation capability has a positive effect on the firm's value offering (VO), the VO has a positive relationship with customer perceived value-in use (PVI), and PVI has a positive relationship with firm performance. This study also finds moderating effects of TFL on the relationship between service innovation capability and VO, and of service marketing capability on the relationship between VO and PVI respectively.

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Purpose This study seeks to extend the existing literature on value creation by specifically focusing on service brand value creation (SBVC) and the role of brand marketing. Design/methodology/approach The authors first develop a model of SBVC and simultaneously investigate SBVC from the firm perspective (service brand value offering – SBVO) and from the customer perspective (service brand perceive value-in use – SBPVI). Subsequently, they investigate the effects of SBVO on SBPVI and integrate the moderation role of service brand marketing capability (SBMC) on the relationship between SBVO-SBPVI outcomes. SBVO is viewed as the firms' interpretation of and responsiveness to customer requirements via the delivery of superior performance the value offering through the service brand and SBPVI customers' perceived value from the firms' service brand. The contributions of SBVC to customer-based performance outcomes are then investigated. Hypotheses were tested using a sample of the senior managers of service firms in Cambodia and their customers. A survey was used to gather data via a drop-and-collect approach. Findings Results indicated that SBVO is positively related to SBPVI and SBPVI is positively related to customer-based performance. Noticeably, the results revealed that SBMC enhances the positive relationship between the firm SBVO and the customers SBPVI. Originality/value The paper extends the previous literature on value creation to capture SBVC. More significantly, the premise of the theoretical framework provides a breakthrough in the current SBVC literature which has so far neglected to take into account the dyadic approach (firm-customer) in understanding value creation and more specifically SBVC. The model is expanded by looking at the contingency role of SBMC in communicating value to customers.

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An increasing range of services are now offered via online applications and e-commerce websites. However, problems with online services still occur at times, even for the best service providers due to the technical failures, informational failures, or lack of required website functionalities. Also, the widespread and increasing implementation of web services means that service failures are both more likely to occur, and more likely to have serious consequences. In this paper we first develop a digital service value chain framework based on existing service delivery models adapted for digital services. We then review current literature on service failure prevention, and provide a typology of technolo- gies and approaches that can be used to prevent failures of different types (functional, informational, system), that can occur at different stages in the web service delivery. This makes a contribution to theory by relating specific technologies and technological approaches to the point in the value chain framework where they will have the maximum impact. Our typology can also be used to guide the planning, justification and design of robust, reliable web services.

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The nature of services and service delivery has been changing rapidly since the 1980’s when many seminal papers in services research were published. Services are increasingly digital, or have a digital component. Further, a large and heterogeneous literature, with competing and overlapping definitions, many of which are dated and inappropriate to contemporary digital services offerings is impeding progress in digital services research. In this conceptual paper, we offer a critical review of some existing conceptualizations of services and digital services. We argue that an inductive approach to understanding cognition about digital services is required to develop a taxonomy of digital services and a new vocabulary. We argue that this is a pre-requisite to theorizing about digital services, including understanding quality drivers, value propositions, and quality determinants for different digital service types. We propose a research approach for reconceptualising digital services and service quality, and outline methodological approaches and outcomes.

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Enacting appropriate behaviors often requires service employees to suppress genuine emotions and/or express other emotions, genuine or contrived. Managing emotions to act in a socially appropriate manner constitutes a form of labor: emotional labor. If labor demands exceed the resources of the employee, burnout arises, with negative consequences for overall psychological well-being and job performance. Similarly, task related activities engender role stress, which can also lead to burnout. Both task related role demands and socio-emotional demands are likely to be omnipresent in interpersonal interactions in service settings. Accordingly, this study sets out to investigate the simultaneous impact of these job demands on burnout in front line service professionals. Based on survey data collected from allied health service workers, the study findings strongly suggest that both socio-emotional demands and task related role demands are significant determinants of workplace stress and that their simultaneous effects on employee burnout can be large.

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Service mismatches involve the adaptation of structural and behavioural interfaces of services, which in practice incurs long lead times through manual, coding e ort. We propose a framework, complementary to conventional service adaptation, to extract comprehensive and seman- tically normalised service interfaces, useful for interoperability in large business networks and the Internet of Services. The framework supports introspection and analysis of large and overloaded operational signa- tures to derive focal artefacts, namely the underlying business objects of services. A more simpli ed and comprehensive service interface layer is created based on these, and rendered into semantically normalised in- terfaces, given an ontology accrued through the framework from service analysis history. This opens up the prospect of supporting capability comparisons across services, and run-time request backtracking and ad- justment, as consumers discover new features of a service's operations through corresponding features of similar services. This paper provides a rst exposition of the service interface synthesis framework, describing patterns having novel requirements for unilateral service adaptation, and algorithms for interface introspection and business object alignment. A prototype implementation and analysis of web services drawn from com- mercial logistic systems are used to validate the algorithms and identify open challenges and future research directions.

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Background  Models of service provision and professional training differ between countries. This study aims to investigate a specialist intellectual disabilities model and a generic mental health model, specifically comparing psychiatrists’ knowledge and competencies, and service quality and accessibility in meeting the mental health needs of people with intellectual disabilities. Method  Data were collected from consultant and trainee psychiatrists within a specialist intellectual disabilities model (UK) and a generic mental health model (Australia). Results  The sample sizes were 294 (UK) and 205 (Australia). Statistically significant differences were found, with UK participants having positive views about the specialist intellectual disabilities service model they worked within, demonstrating flexible and accessible working practices and service provision, responsive to the range of mental health needs of the population with intellectual disabilities, and providing a wide range of treatments and supports. The UK participants were knowledgeable, well trained and confident in their work. They wanted to work with people with intellectual disabilities. In all of these areas, the converse was found from the Australian generic mental health service model. Conclusions  The specialist intellectual disabilities model of service provision and training has advantages over the generic mental health model.

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Throughout a lifetime of operation, a mobile service robot needs to acquire, store and update its knowledge of a working environment. This includes the ability to identify and track objects in different places, as well as using this information for interaction with humans. This paper introduces a long-term updating mechanism, inspired by the modal model of human memory, to enable a mobile robot to maintain its knowledge of a changing environment. The memory model is integrated with a hybrid map that represents the global topology and local geometry of the environment, as well as the respective 3D location of objects. We aim to enable the robot to use this knowledge to help humans by suggesting the most likely locations of specific objects in its map. An experiment using omni-directional vision demonstrates the ability to track the movements of several objects in a dynamic environment over an extended period of time.

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Interaction topologies in service-oriented systems are usually classified into two styles: choreographies and orchestrations. In a choreography, services interact in a peer-to-peer manner and no service plays a privileged role. In contrast, interactions in an orchestration occur between one particular service, the orchestrator, and a number of subordinated services. Each of these topologies has its trade-offs. This paper considers the problem of migrating a service-oriented system from a choreography style to an orchestration style. Specifically, the paper presents a tool chain for synthesising orchestrators from choreographies. Choreographies are initially represented as communicating state machines. Based on this representation, an algorithm is presented that synthesises the behaviour of an orchestrator, which is also represented as a state machine. Concurrent regions are then identified in the synthesised state machine to obtain a more compact representation in the form of a Petri net. Finally, it is shown how the resulting Petri nets can be transformed into notations supported by commercial tools, such as the Business Process Modelling Notation (BPMN).

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Introduction: The role of commercial sex in facilitating infection transmission is a subject of ongoing empirical enquiry, with little attention to the variety and extent of ‘non-traditional’ commercial services that pose a lesser risk of infection. This study sought to examine the supply and demand of a wide range of traditional and non-traditional commercial sexual services among sex workers and their clients from Queensland, Australia. Methods: Cross-sectional convenience sampling was used to compare female sex workers in 1991 (n=200, aged 16-46 years) and 2003 (n=247, aged 18-57 years) and from male clients in 2003. The client sample comprised 160 male clients aged between 19 and 72 years. Results: Over the comparison period there was a significant increase in the provision of ‘exotic’ or non-traditional sexual services. In 2003, the availability of bondage and discipline, submission, fantasy, use of sex toys, golden showers, fisting and lesbian double acts had increased dramatically, while ‘traditional’ services had mostly remained at similar levels. Moreover, the proportion of sex workers in some industry sectors providing ‘exotic’ commercial services seem to have risen over time. Conclusion: Undoubtedly, the sex industry has professionalised and now includes more sophisticated and specialized suppliers. As with any commercial business, the diversification of services is largely driven with client demand, with the ‘menu’ being generally broader than the majority of client preferences. However, although clients demands for particular commercial sexual services seems to have been met, with regard to anal sex and anal play, supply has failed to meet client demand. Disclosure of Interest Statement: Funding for the 2003 study was provided by the Prostitution Licensing Authority. Acknowledgement and sincere thanks to the men and women who participated in this study.

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The conventional measures of benchmarking focus mainly on the water produced or water delivered, and ignore the service quality, and as a result the 'low-cost and low-quality' utilities are rated as efficient units. Benchmarking must credit utilities for improvements in service delivery. This study measures the performance of 20 urban water utilities using data from an Asian Development Bank survey of Indian water utilities in 2005. It applies data envelopment analysis to measure the performance of utilities. The results reveal that incorporation of a quality dimension into the analysis significantly increases the average performance of utilities. The difference between conventional quantity-based measures and quality-adjusted estimates implies that there are significant opportunity costs of maintaining the quality of services in water delivery.