405 research outputs found

    Operational implications of manufacturing outsourcing for subcontractor plants: An empirical investigation

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    Purpose – The objectives of this paper are: to identify the key defining elements of a subcontractor plant from an operations management perspective and examine whether there are differences between the operational contexts of such plants and original equipment manufacturer (OEM) plants; and to examine whether these differences should translate into different operational practices, addressing the specific case of process quality management practices. Design/methodology/approach – The paper uses a multiple case study involving five plants in the electronics industry representative of the OEM and different subcontractor contexts. Findings – Results suggest that the operational contexts of subcontractor and OEM plants are different and that, as a result, these types of plants should emphasize different sets of process quality management practices. Research limitations/implications – Results are considered to be generalizable to most discrete goods industries. However, future research should ascertain whether these results replicate in industries other than electronics. Practical implications – OEMs, who have a critical role in disseminating best practice within the supply chain, must recognize the differences between OEM and subcontractor environments and avoid pushing one-size-fits-all best practice programs along the chain. Originality/value – Research in outsourcing to date has focused on the outsourcing decision per se and has mainly taken the perspective of the outsourcer firm. This study contributes to a better understanding of the operational implications of outsourcing decisions for subcontractor plants. It also responds to calls for more research linking quality management and supply chain management

    Simultaneous Measurement of Middle-Ear Input Impedance and Forward/Reverse Transmission in Cat

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    Reported here is a technique for measuring forward and reverse middle-ear transmission that exploits distortion-product otoacoustic emissions (DPOAEs) to drive the middle ear in reverse without opening the inner ear. The technique allows measurement of DPOAEs, middle-ear input impedance, and forward and reverse middle-ear transfer functions in the same animal. Intermodulation distortion in the cochlea generates a DPOAE at frequency 2f1-f 2 measurable in both ear-canal pressure and the velocity of the stapes. The forward transfer function is computed from stapes velocities and corresponding ear-canal pressures measured at the two primary frequencies; the reverse transfer function is computed from velocity and pressure measurements at the DPOAE frequency. Middle-ear input impedance is computed from ear-canal pressure measurements and the measured ThĂŠvenin equivalent of the sound-delivery system. The technique was applied to measure middle-ear characteristics in anesthetized cats with widely opened middle-ear cavities (0.2-10 kHz). Stapes velocity was measured at the incudo-stapedial joint. Results on five animals are reported and compared with a published middle-ear model. The measured forward transfer functions and input impedances generally agree with previous measurements, and all measurements agree qualitatively with model predictions. The reverse transfer function is shown to depend on the acoustic load in the ear canal, and the measurements are used to compute the round-trip middle-ear gain and delay. Finally, the measurements are used to estimate the parameters of a two-port transfer-matrix description of the cat middle ear

    The Effects of Service Failure and Service Recovery on Customer Loyalty in E-Services: An Empirical Investigation

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    Although there has been a lot of research examining the effect of service failures and recovery on customer loyalty in traditional (bricks-and-mortar) services, there is still little rigorous empirical research examining this in e-service settings. The objective of this study is to empirically examine the impact of service failures and service recovery on customer loyalty in e-services. The study is based on data from an online questionnaire of customers of an e-banking service. The results validated the relationships generally found in traditional services: i) service failures result in decreased customer loyalty intentions; ii) effective recovery from failures increases customer loyalty intentions; and iii) unless recovery efforts elicit very high levels of satisfaction from customers, they can, at best, restore loyalty to the levels existing prior to the failures. The implications for the management of e-services are discussed

    Acoustic Mechanisms that Determine the Ear-Canal Sound Pressures Generated by Earphones

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    In clinical measurements of hearing sensitivity, a given earphone is assumed to produce essentially the same sound-pressure level in all ears. However, recent measurements [Voss et al., Ear and Hearing (in press)] show that with some middle-ear pathologies, ear-canal sound pressures can deviate by as much as 35 dB from the normal-ear value; the deviations depend on the earphone, the middle-ear pathology, and frequency. These pressure variations cause errors in the results of hearing tests. Models developed here identify acoustic mechanisms that cause pressure variations in certain pathological conditions. The models combine measurement-based Thevenin equivalents for insert and supra-aural earphones with lumped-element models for both the normal ear and ears with pathologies that alter the ear\u27s impedance (mastoid bowl, tympanostomy tube, tympanic-membrane perforation, and a \u27high- impedance\u27 ear). Comparison of the earphones\u27 Thevenin impedances to the ear\u27s input impedance with these middle-ear conditions shows that neither class of earphone acts as an ideal pressure source; with some middle-ear pathologies, the ear\u27s input impedance deviates substantially from normal and thereby causes abnormal ear-canal pressure levels. In general, for the three conditions that make the ear\u27s impedance magnitude lower than normal, the model predicts a reduced ear-canal pressure (as much as 35 dB), with a greater pressure reduction with an insert earphone than with a supra-aural earphone. In contrast, the model predicts that ear-canal pressure levels increase only a few dB when the ear has an increased impedance magnitude; the compliance of the air-space between the tympanic membrane and the earphone determines an upper limit on the effect of the middle-ear\u27s impedance increase. Acoustic leaks at the earphone-to-ear connection can also cause uncontrolled pressure variations during hearing tests. From measurements at the supra-aural earphone-to-ear connection, we conclude that it is unusual for the connection between the earphone cushion and the pinna to seal effectively for frequencies below 250 Hz. The models developed here explain the measured pressure variations with several pathologic ears. Understanding these mechanisms should inform the design of more accurate audiometric systems which might include a microphone that monitors the ear-canal pressure and corrects deviations from normal

    Service research priorities in a rapidly changing context

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    The context in which service is delivered and experienced has, in many respects, fundamentally changed. For instance, advances in technology, especially information technology, are leading to a proliferation of revolutionary services and changing how customers serve themselves before, during, and after purchase. To understand this changing landscape, the authors engaged in an international and interdisciplinary research effort to identify research priorities that have the potential to advance the service field and benefit customers, organizations, and society. The priority-setting process was informed by roundtable discussions with researchers affiliated with service research centers and networks located around the world and resulted in the following 12 service research priorities: • stimulating service innovation, • facilitating servitization, service infusion, and solutions, • understanding organization and employee issues relevant to successful service, • developing service networks and systems, • leveraging service design, • using big data to advance service, • understanding value creation, • enhancing the service experience, • improving well-being through transformative service, • measuring and optimizing service performance and impact, • understanding service in a global context, and • leveraging technology to advance service. For each priority, the authors identified important specific service topics and related research questions. Then, through an online survey, service researchers assessed the subtopics’ perceived importance and the service field’s extant knowledge about them. Although all the priorities and related topics were deemed important, the results show that topics related to transformative service and measuring and optimizing service performance are particularly important for advancing the service field along with big data, which had the largest gap between importance and current knowledge of the field. The authors present key challenges that should be addressed to move the field forward and conclude with a discussion of the need for additional interdisciplinary research

    Posture-Induced Changes in Distortion-Product Otoacoustic Emissions and the Potential for Noninvasive Monitoring of Changes in Intracranial Pressure

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    Introduction Intracranial pressure (ICP) monitoring is currently an invasive procedure that requires access to the intracranial space through an opening in the skull. Noninvasive monitoring of ICP via the auditory system is theoretically possible because changes in ICP transfer to the inner ear through connections between the cerebral spinal fluid and the cochlear fluids. In particular, low-frequency distortion-product otoacoustic emissions (DPOAEs), measured noninvasively in the external ear canal, have magnitudes that depend on ICP. Postural changes in healthy humans cause systematic changes in ICP. Here, we quantify the effects of postural changes, and presumably ICP changes, on DPOAE magnitudes. Methods DPOAE magnitudes were measured on seven normal-hearing, healthy subjects at four postural positions on a tilting table (angles 90°, 0°, −30°, and −45° to the horizontal). At these positions, it is expected that ICP varied from about 0 (90°) to 22 mm Hg (−45°). DPOAE magnitudes were measured for a set of frequencies 750\u3cf 2\u3c4000, with f 2/f 1=1.2. Results For the low-frequency range of 750≤f 2≤1500, the differences in DPOAE magnitude between upright and −45° were highly significant (all p\u3c0.01), and above 1500 Hz there were minimal differences between magnitudes at 90° versus −45°. There were no significant differences in the DPOAE magnitudes with subjects at 90° and 0° postures. Conclusions Changes in ICP can be detected using the auditory-based measurement of DPOAEs. In particular, changes are largest at low frequencies. Although this approach does not allow for absolute measurement of ICP, it appears that measurement of DPOAEs may be a useful means of noninvasively monitoring ICP

    Posture Systematically Alters Ear-Canal Reflectance and DPOAE Properties

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    Several studies have demonstrated that the auditory system is sensitive to changes in posture, presumably through changes in intracranial pressure (ICP) that in turn alter the intracochlear pressure, which affects the stiffness of the middle-ear system. This observation has led to efforts to develop an ear-canal based noninvasive diagnostic measure for monitoring ICP, which is currently monitored invasively via access through the skull or spine. Here, we demonstrate the effects of postural changes, and presumably ICP changes, on distortion product otoacoustic emissions (DPOAE) magnitude, DPOAE angle, and power reflectance. Measurements were made on 12 normal-hearing subjects in two postural positions: upright at 90 degrees and tilted at −45 degrees to the horizontal. Measurements on each subject were repeated five times across five separate measurement sessions. All three measures showed significant changes (p \u3c 0.001) between upright and tilted for frequencies between 500 and 2000 Hz, and DPOAE angle changes were significant at all measured frequencies (500–4000 Hz). Intrasubject variability, assessed via standard deviations for each subject’s multiple measurements, were generally smaller in the upright position relative to the tilted position

    “Futurizing” smart service : implications for service researchers and managers

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    Purpose: – The purpose of this paper is to craft a future research agenda to advance smart service research and practice. Smart services are delivered to or via intelligent objects that feature awareness and connectivity. For service researchers and managers, one of the most fascinating aspects of smart service provision is that the connected object is able to sense its own condition and its surroundings and thus allows for real-time data collection, continuous communication and interactive feedback. Design/methodology/approach: – This article is based on discussions in the workshop on “Fresh perspectives on technology in service” at the International Network of Service Researchers on September 26, 2014 at CTF, Karlstad, Sweden. The paper summarizes the discussion on smart services, adds an extensive literature review, provides examples from business practice and develops a structured approach to new research avenues. Findings: – We propose that smart services vary on their individual level of autonomous decision-making, visibility and embeddedness in objects and customer lives. Based on a discussion of these characteristics, we identify research avenues regarding the perception and nature of smart services, the adoption of smart services, the innovation through smart services as well as regarding the development of new business models. Originality/value: – Smart services is a new emerging topic in service marketing research, their implications on organizations, customers and the service landscape have not been fully explored. We provide a fresh perspective on service research by characterizing relevant aspects of smart service that will stimulate fruitful future research and advance the understanding and practice of smart services

    Secondary nucleating sequences affect kinetics and thermodynamics of tau aggregation

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    Tau protein was scanned for highly amyloidogenic sequences in amphiphilic motifs (X)nZ, Z(X)nZ (n≥2) or (XZ)n (n≥2), where X is a hydrophobic residue and Z is a charged or polar residue. N-acetyl peptides homologous to these sequences were used to study aggregation. Transmission electron microscopy (TEM) showed 7 peptides, in addition to well known primary nucleating sequences c275VQIINK (AcPHF6*) and Ac306VQIVYK (AcPHF6), formed fibers, tubes, ribbons or rolled sheets. Of the peptides shown by TEM to form amyloid, Ac10VME, AcPHF6*, Ac375KLTFR, and Ac393VYK were found to enhance the fraction of β-structure of AcPHF6 formed at equilibrium, and Ac375KLTFR was found to inhibit AcPHF6 and AcPHF6* aggregation kinetics in a dose-dependent manner, consistent with its participation in a hybrid steric zipper model. Single site mutants were generated which transformed predicted amyloidogenic sequences in tau into non-amyloidogenic ones. A M11K mutant had fewer filaments and showed a decrease in aggregation kinetics and an increased lag time compared to wild type tau, while a F378K mutant showed significantly more filaments. Our results infer that sequences throughout tau, in addition to PHF6 and PHF6*, can seed amyloid formation or affect aggregation kinetics or thermodynamics

    Analyzing a fleet solution using scenarios

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    Transportation is one of the most important logistics activities, accounting for a significant part of the logistics costs and with high level of impact in terms of the service level provided to the customer. To counteract the upward trend in costs, it is fundamental to identify a transport strategy that can reduce costs and, at the same time, does not adversely affect the service levels agreed with customers. The main objective of this research is to propose a methodology for companies to identify, from a set of scenarios proposed and through a comparative analysis of scenarios, a new fleet solution, allowing the Company under study to reduce its transport costs without harming the current service level agreements with its customers. This research is grounded on a case study methodology. The case study used is of a small Portuguese company that produces, imports and distributes a wide range of products. The distribution is conducted based on both its own fleet and subcontracted transportation. The comparative analysis of scenarios allowed identifying the current transportation solution as the most advantageous one for the company. A roadmap to address fleet solution is provided.info:eu-repo/semantics/acceptedVersio
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