410 research outputs found

    Antecedents and Outcomes of Customer Engagement: Bridging Customer Value Co-Creation Behavior and Customer Psychological State Engagement

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    This dissertation draws on service-dominant logic and reviews the engagement literature to explore the antecedents and outcomes of two multi-dimensional customer engagement constructs: psychological state engagement (PSEngagement) and value co-creation behavior. PSEngagement is a precursor to value co-creation behavior, with the latter also known as behavioral engagement in prior research. The model proposed in this dissertation was tested in two service contexts: higher education, with a sample size of 454, and fitness, with a sample size of 122. To minimize the common method variance typical of survey research (Podsakoff, et al. 2003), the model was tested twice per context, once using self-report data only, and the second time using a combination of self-report and objective data. This dissertation integrates two research streams by including customer engagement and customer value co-creation behavior, explores the conceptual and operational definitions of each, and models their antecedents and outcomes. This research is important for theoretical as well as practical reasons. Theoretically, it contributes by corroborating the interplay between PSEngagement and value co-creation behavior and by examining that interplay within the broader nomological network of antecedents and outcomes. For practitioners, this research identifies the positive outcomes of having engaged customers as well as the mechanisms through which firms can engage customers

    Some Pre-filters in EQ-Algebras

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    In this paper, the notion of an obstinate prefilter (filter) in an EQ-algebra ξ is introduced and a characterization of it is obtained by some theorems. Then the notion of maximal prefilter is defined and is characterized under some conditions. Finally, the relations among obstinate, prime, maximal, implicative and positive implicative prefilters are studied

    Evaluation of Progressive Collapse Performance in Double layer Diamatic Domes

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    Double-layer spatial domes are one of the most common spatial structures, the stability and progressive collapse of which are of great importance in design, construction and maintenance of such special structures. In this paper considering three loading cases and two types of support conditions, the collapse behaviour of double layer Diamatic dome has been investigated utilizing non-linear static analysis and alternate path method usage. In order to modelling compressive member behaviour, effective buckling modes have been obtained by eigenvalue buckling analysis for all of the members. Behaviour of compressive members has been obtained via definition of initial imperfection and non-linear static analysis. Riks arc-length method has been utilized for non-linear static analysis. The numerical results have indicated that reducing the number of the supports and focusing  of load in a local area of the dome extremely impact on its vulnerability to failure, as in similar loading condition, decreasing the number of the supports reduces the capacity of damage resistance in spatial domes up to 50 percent. Investigating some models has shown that removing the critical members of the top layer has little effect on load-bearing capacity of the dome and it causes a slight failure in the structure. In this condition, structural redundancy can be considered equal to static indeterminacy. Load bearing capacity of the structure decreased up to 39 percent when compressive members of the web and bottom layers were removed. In this condition, the structure failure is considered moderate

    Utilization of a carbon-dioxide laser to form an amorphous metallic layer on gray cast iron with various amount of boron

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    The study of the amorphous metals in important because of their technological usefulness. One class of these materials, iron-based metallic glass, has shown great promise in application because of the superior chemical, mechanical, electrical, and magnetic properties of these materials. This study was conducted to examine the capability of a medium-powered carbon-dioxide laser to form an amorphous metallic layer on the surface of a ferritic gray cast iron in order to improve the wear and corrosion resistance of engineered components. Boron was used as an alloying element for the retardation of nucleation and for the formation of the amorphous metallic layer. Homogenization heat treatment was followed by vacuum emission spectroscopy, which provided the quantitative information related to the chemical composition prior to the laser processing. The laser parameters were chosen and they were examined experimentally to identify the optimum conditions for the process. The characteristics of the laser-formed layer on the surface of specimens were determined by chemical testing, x-ray diffraction techniques, scanning electron microscopy, and electron diffraction techniques to substantiate the formation of the metallic glass layer and examine its features. Micro-hardness examination was used to determine the hardness profile of the generated layer at the heat-affected zone. Metallographic examination provided such information as the surface condition, the depth of the fusion zone, and any defects caused by the process. The test results led to the conclusion that the carbon-dioxide laser, with medium power output within a certain range of operation, is capable of forming metallic glass structures on the surface of gray cast iron, alloyed with boron. In such a process, the laser must operate at the pulse mode generating a pulse with short width and long dwell time. In addition, the boron content of the sample should be in the range of 3.8 (eutectic point) to 4.17 percent by weight. The specimen with 8 percent boron content, after it was irradiated with the laser at the continuous mode, also produced an interlocking structure often seen in glassy structures. The identification and characterization of this structure was not within the scope of this investigation. The hardness measurement of the untreated surface showed a notable increase in the hardness of the specimen containing two percent boron. The micro-hardness examination of the laser-treated area revealed that the treatment caused a further increase in the micro-hardness of the specimens. Electron Diffraction Spectro-Analysis of the laser heat treated zones did not conform to the structures predicted by the iron-carbon-boron and iron-carbon-silicon ternary diagrams. The laser treated surfaces produced a super-saturated structure with a high hardness and good resistance to corrosion

    Value-Focused Assessment of Information System Security in Organizations

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    This paper presents findings of an empirical study of information system (IS) security values adhered to by user managers in a cross section of firms in various industries. Using Keeneyís (1999) value-focused thinking approach, 73 managers were interviewed to identify a set of fundamental and means values that are essential in protecting the information resources of a firm. The findings are used to develop a theoretical framework for conceptualizing individual and organizational issues in managing IS security. The proposed framework will be an appropriate underpinning for the development of an instrument for measuring IS security concerns

    Dual commutative hyper-K-idelas of type 1 in hyper K-algebras of order 3

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    In this note we classify the bounded hyper K-algebras of order 3, which have D1 = {1}, D2 = {1, 2} and D3 = {0, 1} as a dual commutative hyper K-ideal of type 1. In this regard we show that there are such non-isomorphic bounded hyper K-algebras

    Recombinant production of Annexin V protein for apoptosis detection to monitor cancer therapy

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    Introduction: Apoptosis or programmed cell death (PCD) plays an important role not only in physiology but also in pathology. One of the most prominent features of apoptosis is externalization of phosphatidylserine (PS), which in healthy cells are located in the inner leaflet of the plasma membrane. PS-externalization have made a well-explored phenomenon to image cell death for diagnostic and therapeutic purposes. Since many drugs induce a therapeutic effect through the activation of PCD in target cells, imaging of cell death offers a direct way to image therapy response. Moreover, failure of therapy is frequently a result of resistance against apoptosis. Therefore detection and quantification of apoptosis are some of the significant clinical value for diagnosis and assessment for  therapeutic efficacy. In this research we emphasize the expression and purification of recombinant polyhistidine-tagged human annexin V protein that binds to PS with high affinity and has been developed as a molecular imaging agent to measure cell death in vitro and  in vivo in animal models and in patients with cardiovascular diseases and cancer. We also describe conjugation of this protein to the Fluorescein isothiocyanate (FITC) fluorophore for the detection of apoptotic cells by flow cytometry or fluorescence microscopy. Methods and Results: In this project we transformed recombinant plasmid including annexin V gene into competent BL21 strain. after an overnight incubation at 37°C in LB medium,1 mL of that was used to inoculate 100 mL of TB culture. The expression of annexin V was induced with 1 mM IPTG (isopropyl-b-D-thiogalactopyranoside). The expression level of annexin V was evaluated by SDS-PAGE. Recombinant annexin V was expressed and purified to high yields. FITC as the fluorescent conjugate and a signal detector was used to attach to annexin V. we detected apoptotic cells in culture by annexin V-FITC produced probe in real time, using fluorescence microscopy and flow cytometry.  Conclusions: Annexin V staining is a simple and widely used method for detection of apoptosis in a rapid and highly quantitative manner for both early monitoring of therapy capability and assessment of disease development

    Fast Converging Evolutionary Strategy for Multi-Constraint QoS Routing in Computer Networks Using New Decoding Mechanism

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    In recent years, real-time multimedia applications' demands such as Voice-on-IP (VoIP) and video conference are extremely increased which require QoS routing. This type of routing has been considered as an NP-Complete problem since it requires satisfying multiple constraints. Many solutions have been proposed to solve it, but most of them are complex and time consuming. In this paper, a novel multi-constraints QoS routing algorithm is proposed based on Evolutionary Strategies (ES). The algorithm preserves simplicity and offers a feasible solution in a few numbers of generations. This is due to a novel gene decoding mechanism that is used in the algorithm; and consequently more simple evolutionary operators can be applied. The simulation results show that our method outperforms previous algorithms in terms of speed and performance, so that it is 2.6 and 11.3 times faster, and its success ratio is also better
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