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81.
Examining influencing factors of post-adoption usage of mobile internet: Focus on the user perception of supplier-side attributes 总被引:1,自引:0,他引:1
Young Mee Shin Seung Chang Lee Bongsik Shin Ho Geun Lee 《Information Systems Frontiers》2010,12(5):595-606
Key supplier-side factors that affect the usage level of mobile Internet were identified and the procedural mechanism among
the independent and dependent variables was investigated. For this, a research model was introduced to describe associations
among four external variables (access quality, service variety, cost rationality, and ease of use), an intermediate variable
(usefulness) and a dependent variable (the usage level of mobile Internet). Through the on-line survey, data were gathered
from actual mobile Internet users. Confirmatory factor analysis and path analysis were applied to test the overall integrity
of the research model and of proposed hypotheses. All four external variables affected user perceptions on the usefulness
of mobile Internet. Among them, service variety and cost rationality had a relatively larger influence on perceived usefulness.
Perceived usefulness of the mobile Internet had a positive effect on its usage, confirming the important role of usefulness
as a significant mediator between the four external variables and the dependent variable. Meanwhile, the cost rationality
was the only external variable with direct influence on the MI usage. Theoretical and practical implications of the study
results are discussed. 相似文献
82.
Usage of frequency based error correction methods for repetitive disturbances becomes popular in data storage devices that use a rotating mechanical power plant. Two distinct disturbance cancellation methods, disturbance observer (DOB) and adaptive feed forward control (AFC) are the most popular approaches used for current drive servo integration. DOB reduces error using a predetermined function that is calculated thorough a complicated process. Generally the response to disturbance and initiation of control action of DOB is relatively fast even if the amount of error reduction is limited. Meanwhile the error elimination capability of AFC for the repetitive disturbance is normally better than DOB as it utilizes a Fourier coefficients updating feature that supports an enhanced fine adaptation of a certain frequency disturbance. Of course, AFC suffers for disturbances that have neighboring close frequencies due to the inherent fundamental frequency dependencies of AFC formulation. In the present work, an attempt for combining benefits of AFC and DOB is made. This might enables control action not only to generate fast response to disturbance but also perform an accurate error rejection. This feature also provides to the closed loop system a frequency selection for enabling a strategic selective error rejection. The proposed method named Hybrid Disturbance Observer (HDOB) is compared to the traditional AFC and DOB. 相似文献
83.
Browsing the DOM tree of an XML document is an act of following the links among the nodes of the DOM tree to find some desired nodes without any knowledge for search. When the structure of the XML document is not known to a user, browsing is the basic operation performed for referring the contents of the XML document. If the size of the XML document is very large, however, using a general-purpose XML parser for browsing the DOM tree of the XML document to access arbitrary node may suffer from the lack of memory space for constructing the large DOM tree. To alleviate this problem, we suggest a method to browse the DOM tree of a very large XML document by splitting the XML document into n small XML documents and generating sequentially the DOM tree of each of those small n XML documents. For later reference, the information of some nodes accessed from the DOM tree already generated has been also kept using the concept of their virtual nodes. With our suggested approach, the memory space necessary for browsing the DOM tree of a very large XML document is reduced such that it can be managed by a personal computer. 相似文献
84.
In this paper, we propose a method to jointly transfer the color and detail of multiple source images to a target video or image. Our method is based on a probabilistic segmentation scheme using Gaussian mixture model (GMM) to divide each source image as well as the target video frames or image into soft regions and determine the relevant source regions for each target region. For detail transfer, we first decompose each image as well as the target video frames or image into base and detail components. Then histogram matching is performed for detail components to transfer the detail of matching regions from source images to the target. We propose a unified framework to perform both color and detail transforms in an integrated manner. We also propose a method to maintain consistency for video targets, by enforcing consistent region segmentations for consecutive video frames using GMM-based parameter propagation and adaptive scene change detection. Experimental results demonstrate that our method automatically produces consistent color and detail transferred videos and images from a set of source images. 相似文献
85.
Seung Jae Lee 《Information Systems Frontiers》2017,19(4):705-715
The tourism industry is intimately related to the development of technology. Currently, technology-integrated “smart tourism” provides convenience and interactivity, and offers personalized services to tourists. However, the use of the technology-mediated audio guides among tourists in cultural heritage sites is not as active as expected. The underutilization of the audio guides in palaces is confirmed by a survey at Gyeongbok-gung palace, and the underlying reasons are examined by interviewing visitors to Chateau de Versailles. This paper analyzes the low usage of audio guides as a case-study, utilizing Cohen’s basic concepts of tour guides, Dann’s tourist motivation theory and the museum ecology of Bell. Consequently, this paper confirms the multifunctional complexity of audio guides, and suggests improvement of them in functionality (user-friendliness, usability, interactivity and social functions) for program developers, and the strategic use of ICT in promotion of palaces as smart tourism destination in cultural heritage management. 相似文献
86.
Stephen G. McGill Seung‐Joon Yi Hak Yi Min Sung Ahn Sanghyun Cho Kevin Liu Daniel Sun Bhoram Lee Heejin Jeong Jinwook Huh Dennis Hong Daniel D. Lee 《野外机器人技术杂志》2017,34(4):775-801
This paper describes Team THOR's approach to human‐in‐the‐loop disaster response robotics for the 2015 DARPA Robotics Challenge (DRC) Finals. Under the duress of unpredictable networking and terrain, fluid operator interactions and dynamic disturbance rejection become major concerns for effective teleoperation. We present a humanoid robot designed to effectively traverse a disaster environment while allowing for a wide range of manipulation abilities. To complement the robot hardware, a hierarchical software foundation implements network strategies that provide real‐time feedback to an operator under restricted bandwidth using layered user interfaces. Our strategy for humanoid locomotion includes a backward‐facing knee configuration paired with specialized toe and heel lifting strategies that allow the robot to traverse difficult surfaces while rejecting external perturbations. With an upper body planner that encodes operator preferences, predictable motion plans are executed in unforeseen circumstances. These plans are critical for manipulation in unknown environments. Our approach was validated during the DRC Finals competition, where Team THOR scored three points in 18 min of operation time, and the results are presented along with an analysis of each task. 相似文献
87.
Jino Heo Min-Sung Kang Chang-Ho Hong Hyeon Yang Seong-Gon Choi 《Quantum Information Processing》2017,16(1):24
We propose quantum information processing schemes based on cavity quantum electrodynamics (QED) for quantum communication. First, to generate entangled states (Bell and Greenberger–Horne–Zeilinger [GHZ] states) between flying photons and three-level atoms inside optical cavities, we utilize a controlled phase flip (CPF) gate that can be implemented via cavity QED). Subsequently, we present an entanglement swapping scheme that can be realized using single-qubit measurements and CPF gates via optical cavities. These schemes can be directly applied to construct an entanglement channel for a communication system between two users. Consequently, it is possible for the trust center, having quantum nodes, to accomplish the linked channel (entanglement channel) between the two separate long-distance users via the distribution of Bell states and entanglement swapping. Furthermore, in our schemes, the main physical component is the CPF gate between the photons and the three-level atoms in cavity QED, which is feasible in practice. Thus, our schemes can be experimentally realized with current technology. 相似文献
88.
Contour matching using epipolar geometry 总被引:15,自引:0,他引:15
Joon Hee Han Jong Seung Park 《IEEE transactions on pattern analysis and machine intelligence》2000,22(4):358-370
Matching features computed in images is an important process in multiview image analysis. When the motion between two images is large, the matching problem becomes very difficult. In this paper, we propose a contour matching algorithm based on geometric constraints. With the assumption that the contours are obtained from images taken from a moving camera with static scenes, we apply the epipolar constraint between two sets of contours and compute the corresponding points on the contours. From the initial epipolar constraints obtained from corner point matching, candidate contours are selected according to the epipolar geometry, contour end point constraints, and contour distance measures. In order to reduce the possibility of false matches, the number of match points on a contour is also used as a selection measure. The initial epipolar constraint is refined from the matched sets of contours. The algorithm can be applied to a pair or two pairs of images. All of the processes are fully automatic and successfully implemented and tested with various real images 相似文献
89.
Optimization of 3.5-in. HDD spindle motors for OP-vibration performance: theoretical prediction and experimental verification 总被引:1,自引:1,他引:0
The purpose of this paper is to optimize OP-vibration performance of 3.5-in. hard disk drive (HDD) spindle motors through theoretical prediction and experimental verification. OP-vibration performance of HDD is closely related to the first rocking vibration of spindle motors because excited frequencies of 3.5-in. HDD from the environment are mostly below 500 Hz and the first rocking vibration is the only resonance in the corresponding frequencies. Therefore, minimizing first rocking vibration leads to improve OP-vibration performance of the spindle motors. In order to minimize the first rocking vibration key parameters of FDB spindle motors were selected from a previous work done by Heo and Shen (Microsyst Technol 11:1204–1213, 2005). Then, the selected parameters have been optimized to minimize the first rocking vibration through a theoretical model developed at University of Washington. Then, experiments with ten prototype FDB spindle motors have been conducted to verify the theoretical results. Each prototype motor has different spindle parameter configurations including bearing coefficients, bearing locations, and center of gravity location, etc. Also, this paper demonstrated that radial measurements of spindle rocking vibration have better correlation with OP-vibration performance than axial measurements through PES measurements. Finally, the optimized design has been manufactured by a motor maker and has also successfully verified the theoretical prediction experimentally. 相似文献
90.
Multimedia systems design generally requires a collaborative effort from a group of designers with a variety of backgrounds and tasks, such as content experts, instructional designers, media specialists, users, and so forth. However, currently available design tools on the market are mainly designed for a single user. Tools intended to support a collaborative design process should coordinate independent activities of individual designers.This research investigated support for work groups engaged in designing multimedia systems. Specifically, it discussed a new collaborative design environment, called the KMS (Knowledge Management System)-based design environment, in which multimedia designers could share their design knowledge freely. Through two experimental groups, the research investigated impacts of the KMS-based design environment on their collaborative design activities (knowledge creating, knowledge securing, knowledge distributing, and knowledge retrieving activities). The research findings showed that the KMS-based design environment was a promising environment for collaborative multimedia systems design. More specifically, the research findings indicated that the KMS-based design environment supported creating, securing, and retrieving knowledge, but it did not support distributing knowledge. In addition, the research found that the social interactions between group members played important roles in the success of the collaborative multimedia systems design and that the KMS-based design environment did not support the socialization of group members. Furthermore, the research found that the inability of the KMS-based design environment to support the socialization was linked to its low performance level in supporting the knowledge distributing activity. The research explored the desired features of a collaborative support tool for multimedia systems design. 相似文献