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32.
Online social networks (OSN) are technology-enabled relationship tools in which a user creates a profile, connects to other individuals, and shares user-generated content with them. One of the many features OSN offer is the ability to post messages in the form of product and service recommendations. Although word-of-mouth research has examined this type of personal communication to intentionally influence consumer decisions, limited understanding exists regarding when a user acts upon a recommendation received from one of their contacts. In this study, we draw on relationship theories and research on trust to analyze the impact relationship characteristics and behaviors of the OSN contacts have on trust in the recommendation that subsequently leads a user to act on this OSN contact’s recommendation. The results of a survey of 116 OSN users showed that closeness, excessive posting behavior, and past recommendation experience have a positive impact on trust and intention to act on the recommendation. One characteristic of the relationships, that is, similarity, however, does not affect recommendation trust in the context of OSN. The findings enhance our understanding of relationships and their defining characteristics in OSN. The results also provide insights into how companies might leverage OSN in their marketing efforts. 相似文献
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34.
Leonid B. Freidovich Pedro La Hera Uwe Mettin Anders Robertsson Anton S. Shiriaev Rolf Johansson 《Asian journal of control》2009,11(5):548-556
We consider an underactuated two‐link robot called the inertia wheel pendulum. The system consists of a free planar rotational pendulum and a symmetric disk attached to its end, which is directly controlled by a DC‐motor. The goal is to create stable oscillations of the pendulum, which is not directly actuated. We exploit a recently proposed feedback‐control design strategy based on motion planning via virtual holonomic constraints. This strategy is shown to be useful for design of regulators for achieving orbitally exponentially stable oscillatory motions. The main contribution is a step‐by‐step procedure on how to achieve oscillations with pre‐specified amplitude from a given range and an arbitrary independently chosen period. The theoretical results are verified via experiments with a real hardware setup. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
35.
Nordahl R Turchet L Serafin S 《IEEE transactions on visualization and computer graphics》2011,17(9):1234-1244
We propose a system that affords real-time sound synthesis of footsteps on different materials. The system is based on microphones, which detect real footstep sounds from subjects, from which the ground reaction force (GRF) is estimated. Such GRF is used to control a sound synthesis engine based on physical models. Two experiments were conducted. In the first experiment, the ability of subjects to recognize the surface they were exposed to was assessed. In the second experiment, the sound synthesis engine was enhanced with environmental sounds. Results show that, in some conditions, adding a soundscape significantly improves the recognition of the simulated environment. 相似文献
36.
Michael A. Bender Gerth Stølting Brodal Rolf Fagerberg Riko Jacob Elias Vicari 《Theory of Computing Systems》2010,47(4):934-962
We study the problem of sparse-matrix dense-vector multiplication (SpMV) in external memory. The task of SpMV is to compute
y:=Ax, where A is a sparse N×N matrix and x is a vector. We express sparsity by a parameter k, and for each choice of k consider the class of matrices where the number of nonzero entries is kN, i.e., where the average number of nonzero entries per column is k. 相似文献
37.
Arnaud Grasset Philippe Millet Philippe Bonnot Sami Yehia Wolfram Putzke-Roeming Fabio Campi Alberto Rosti Michael Huebner Nikolaos S. Voros Davide Rossi Henning Sahlbach Rolf Ernst 《International journal of parallel programming》2011,39(3):328-356
Reconfigurable computing offers a wide range of low cost and efficient solutions for embedded systems. The proper choice of the reconfigurable device, the granularity of its processing elements and its memory architecture highly depend on the type of application and their data flow. Existing solutions either offer fine grain FPGAs, which rely on a hardware synthesis flow and offer the maximum degree of flexibility, or coarser grain solutions, which are usually more suitable for a particular type of data flow and applications. In this paper, we present the MORPHEUS architecture, a versatile reconfigurable heterogeneous System-on-Chip targeting streaming applications. The presented architecture exploits different reconfigurable technologies at several computation granularities that efficiently address the different applications needs. In order to efficiently exploit the presented architecture, we implemented a complete software solution to map C applications to the reconfigurable architecture. In this paper, we describe the complete toolset and provide concrete use cases of the architecture. 相似文献
38.
Holger Maune Mohsen Sazegar Yuliang Zheng Xianghui Zhou Andre Giere Patrick Scheele Florian Paul Joachim R. Binder Rolf Jakoby 《Microsystem Technologies》2011,17(2):213-224
The research on materials and systems for tunable microwave devices has gained attraction within the last years. The radio
frequency characterization and the component design of tunable microwave components based on dielectric ceramics especially
barium-strontium-titanate (BST) are presented in this second part, whereas the basic material properties are discussed in
detail in the first part. After a short introduction to the processing technology used for the fabrication of tunable components
based on a BST thick film, the relations between microwave properties and material properties as well as the microstructure
are presented in detail. The design process for tunable microwave components based on BST thick films is described. Especially
the considerations related to micro- and macrostructure and their connection are highlighted. The paper closes with two different
application examples: a reconfigurable array antenna for satellite communication and varactors for high power applications. 相似文献
39.
Sabine Schlabach Rolf Ochs Thomas Hanemann Doroth��e Vinga Szab�� 《Microsystem Technologies》2011,17(2):183-193
Regarding the development of nanoparticles for polymer matrix composites the particle/agglomerate size and particle/agglomerate
distribution in the composites, respectively, is often crucial. This is exemplarily shown for, e.g. optical applications with
measurements of refractive index and transmittance. Classical blending techniques, where nanoparticles are dispersed in polymers
or resins, are compared to a combination of a special gas-phase synthesis method with subsequent in-situ deposition of nanoparticles
in high-boiling liquids. The particles/agglomerates were characterized regarding particle size and particle size distribution
using transmission electron microscopy and dynamic light scattering. Additionally, important material properties like mechanical
properties, relevant for application, or like viscosity, relevant for processing, are determined. It is shown, that with in-situ
dispersed nanoparticles synthesized in a microwave plasma process composites with finely dispersed particles/agglomerates
are attainable. 相似文献
40.
Valence electron energy-loss spectroscopy (VEELS) performed in a monochromated scanning transmission electron microscope was used to measure the energy gaps of individual quantum dots (QDs). The gap energies of a series of CdSe QDs measured by VEELS reveal the expected quantum confinement effect; the gap energy increases with decreasing particle size. However, the values derived from these first VEELS measurements of single QDs are larger than the values commonly measured by optical spectroscopy. As standard optical methods lack the spatial resolution to probe individual nanoparticles, the particle-size distribution influences the optical response. It is suggested that the impact of the particle-size distribution accounts for the discrepancy between the energy-gap values derived from VEELS of single QDs and from optical methods of ensembles of QDs. 相似文献