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21.
Organisations have invested in self‐service information systems (IS) to provide a direct interface for service delivery. Enriching the usage of these systems can provide organisations with immense benefits. However, limited research has been directed towards understanding post‐adoption IS usage behaviour in general and specifically in the context of self‐service IS. This study proposes post‐adoption IS usage behaviour as a broader concept constituting feature level usage of IS, integration of IS in the work system and exploration of new uses of IS. We evaluate how the new conceptualisation can be used to classify users at different stages of self‐service IS usage. Further, we examine user perceptions that differentiate among the users situated at different self‐service IS usage stages. Data were collected in the context of a self‐service Web‐based IS to validate the post‐adoption IS usage constructs and to examine the proposed thesis. The newly developed conceptual structure and measures for post‐adoption IS usage behaviour exhibit strong psychometric properties. The analysis shows three distinct post‐adoption IS usage stages and highlights that usefulness, user‐initiated learning, ease of use, satisfaction and voluntariness of use differentiate users at the different stages of post‐adoption IS usage. The results show that these variables aggregate into value confirmation and learning orientation as two higher‐level concepts. Further, we evaluate the predictive efficacy of the research model in classifying users into different post‐adoption self‐service IS usage stages. Implications are drawn for future research. 相似文献
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This paper presents an innovative micro gyroscope design. The proposed tri-axis gyroscope possesses the capability of detecting
three-dimensional angular motions. The motion of each sensing element is, by elaborate mechanical design, restricted to move
in orthogonal direction to each other such that the measurements by high-resolution capacitors with signal processing circuits
are decoupled and precisely represent, to some extent, angular velocity components in three axes. The drive electrode comb
is used to constantly vibrate the proof mass in tangential direction by sinusoidal voltage. The signal bandwidth is increased
by distributed translational proof masses, placed ninety degree apart from each other. Each individual proof mass is designed
to move solely in radial direction so that superior mode matching can be achieved. In order to ensure better repeatability
and more reliability, the suspension flexures and damping effects are studied such that stress of the proposed micro gyroscope
is reduced but the span of angular displacements is increased. Owing to the complicated geometry of the suspension flexures,
finite element method (FEM) is employed to obtain more exact stiffness values and compared with theoretical analysis. The
dynamic model of the proposed gyroscope is established to include non-linear terms and embedded mechanical constraints. The
entire micro device can be produced merely by surface fabrication such that the mass production cost can be considered at
the design stage, while the resolution, bandwidth and decoupling capability of tri-axis detection are enhanced. 相似文献
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This study investigates Chinese consumers’ adoption of the innovative 3D printing systems for small-scale manufacturing in home settings. Empirical studies were conducted in a survey with 256 participants. The number of significant determinants that affect an individual’s decision to adopt 3D printing systems has been identified by applying a model that integrates the Technology Acceptance Model and Innovation Diffusion Theory. A number of moderation effects of demographic variables (e.g. gender, design background) on the association between motivational variables and participants’ adoption have also been analysed with factor analysis, structural equation modelling and hierarchical regression. Our results shed some light on the characteristics of early adopters of home 3D printing systems in China. This study contributes to the early understanding of Chinese consumers’ adoption of innovative 3D printing systems. 相似文献
28.
Zhe Liang Wanpracha Art Chaovalitwongse Meeyoung Cha Sue B. Moon 《Computers & Operations Research》2010,37(10):1731-1739
This paper presents a redundant multicast routing problem in multilayer networks that arises from large-scale distribution of realtime multicast data (e.g., Internet TV, videocasting, online games, stock quotes). Since these multicast services commonly operate in multilayer networks, the communications paths need to be robust against a single router or link failure as well as multiple such failures due to shared risk link groups (SRLGs). The main challenge of this multicast is to ensure the service availability and reliability using a path protection scheme, which is to find a redundant path that is SRLG-disjoint (diverse) from each working path. The objective of this problem is, therefore, to find two redundant multicast trees, each from one of the two redundant sources to every destination, at a minimum total communication cost whereas two paths from the two sources to every destination are guaranteed to be SRLG-diverse (i.e., links in the same risk group are disjoint). In this paper, we present two new mathematical programming models, edge-based and path-based, for the redundant multicast routing problem with SRLG-diverse constraints. Because the number of paths in path-based model grows exponentially with the network size, it is impossible to enumerate all possible paths in real life networks. We develop three approaches (probabilistic, non-dominated and nearly non-dominated) to generate potentially good paths that may be included in the path-based model. This study is motivated by emerging applications of internet-protocol TV service, and we evaluate the proposed approaches using real life network topologies. Our empirical results suggest that both models perform very well, and the nearly non-dominated path approach outperforms all other path generation approaches. 相似文献
29.
Driven by the complexity of new products and services, project work has become increasingly common in all types of organizations. However, research on project learning suggests that often project teams do not meet their stated objectives and, moreover, there is limited organizational learning from the experiences of project work. We use the dynamic capabilities framework to argue that building a dynamic project learning capability is useful for organizations that make extensive use of projects. We use both survey and interview data to discuss the key ways in which such a dynamic capability can be built. Our survey data demonstrate the importance of documenting project learning, but our interview data show that teams are often remiss at documenting their learning. The results from the two different approaches are synthesized using Boland & Tenkasi’s notions of perspective‐making and perspective‐taking. Importantly, combining the results from the two sets of data suggests that organizations need to emphasize the benefits from project reviews and documentation and explore ways in which the documents produced can be made more useful as boundary objects to encourage the sharing of learning across projects. 相似文献
30.
Pula G Perera S Prokopi M Sidibe A Boulanger CM Mayr M 《Proteomics. Clinical applications》2008,2(6):882-891
The release of proteins and membrane vesicles in the bloodstream regulates diverse vascular processes, both physiological, such as angiogenesis and haemostasis, and pathological, such as atherosclerosis and atherothrombosis. Proteomics, beside its canonical application for the expression profiling in cells and organs, can be applied to the study of secreted proteins and microvesicles, which play a significant role in the homeostasis of the vasculature, and the development of the atherosclerotic disease. 相似文献