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61.
62.
M. Oliver 《Journal of Computer Assisted Learning》2011,27(5):373-384
This paper argues that research on the educational uses of technology frequently overemphasizes the influence of technology. Research in the field is considered a form of critical perspective, and assumptions about technology are questioned. Technological determinism is introduced, and different positions on this concept are identified. These are used to discuss the ways in which work within the field might be described as technologically deterministic. Four theoretical perspectives (activity theory, communities of practice, actor–network theory, and the social construction of technology) are then briefly characterized, demonstrating that alternative positions are viable, and positioning each in relation to the earlier discussion of technological determinism. The paper concludes by arguing that research, building on such alternative conceptions of technology, is important in developing our understanding of the relationship between technology and learning, as well as identifying potential methodological implications. 相似文献
63.
64.
The Stanford Event Heap has been shown to provide appropriate support for constructing interactive workspace applications.
Given this success it is natural to consider the Event Heap as a platform to support other classes of Ubiquitous Computing
applications. In this paper we argue that the distributed, spontaneous nature of these applications places additional demands
on the Event Heap that require extensions to both the engineering and API. Suitable extensions are described and their use
to support a typical Ubicomp application is discussed.
相似文献
Oliver Storz (Corresponding author)Email: |
Adrian FridayEmail: |
Nigel DaviesEmail: |
65.
Oliver BG 《Environmental science & technology》1983,17(2):80-83
66.
Social Network Sites (SNSs) rely exclusively on user-generated content to offer engaging and rewarding experience to its members. As a result, stimulating user communication and self-disclosure is vital for the sustainability of SNSs. However, considering that the SNS users are increasingly culturally diverse, motivating this audience to self-disclose requires understanding of their cultural intricacies. Yet existing research offers only limited insights into the role of culture behind the motivation of SNS users to self-disclose. Building on the privacy calculus framework, this study explores the role of two cultural dimensions ?C individualism and uncertainty avoidance ?C in self-disclosure decisions of SNS users. Survey responses of US and German Facebook members are used as the basis for our analysis. Structural equation modeling and multi-group analysis results reveal the distinct role of culture in the cognitive patterns of SNS users. The authors find that trusting beliefs play a key role in the self-disclosure decisions of users from individualistic cultures. At the same time, uncertainty avoidance determines the impact of privacy concerns. This paper contributes to the theory by rejecting the universal nature of privacy calculus processes. The findings provide for an array of managerial implications for SNS providers as they strive to encourage content creation and sharing by their heterogeneous members. 相似文献
67.
Schultheiss Oliver C.; Pang Joyce S.; Torges Cynthia M.; Wirth Michelle M.; Treynor Wendy 《Canadian Metallurgical Quarterly》2005,5(1):41
Participants (N = 216) were administered a differential implicit learning task during which they were trained and tested on 3 maximally distinct 2nd-order visuomotor sequences, with sequence color serving as discriminative stimulus. During training, 1 sequence each was followed by an emotional face, a neutral face, and no face, using backward masking. Emotion (joy, surprise, anger), face gender, and exposure duration (12 ms, 209 ms) were varied between participants; implicit motives were assessed with a picture-story exercise. For power-motivated individuals, low-dominance facial expressions enhanced and high-dominance expressions impaired learning. For affiliation-motivated individuals, learning was impaired in the context of hostile faces. These findings did not depend on explicit learning of fixed sequences or on awareness of sequence-face contingencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Waks E. Inoue K. Oliver W.D. Diamanti E. Yamamoto Y. 《IEEE journal of selected topics in quantum electronics》2003,9(6):1502-1511
The visible light photon counter (VLPC) features high quantum efficiency (QE) and low pulse height dispersion. These properties make it ideal for efficient photon-number state detection. The ability to perform efficient photon-number state detection is important in many quantum information processing applications, including recent proposals for performing quantum computation with linear optical elements. In this paper, we investigate the unique capabilities of the VLPC. The efficiency of the detector and cryogenic system is measured at 543 nm wavelengths to be 85%. A picosecond pulsed laser is then used to excite the detector with pulses having average photon numbers ranging from 3-5. The output of the VLPC is used to discriminate photon numbers in a pulse. The error probability for number state discrimination is an increasing function of the number of photons, due to buildup of multiplication noise. This puts an ultimate limit on the ability of the VLPC to do number state detection. For many applications, it is sufficient to discriminate between 1 and more than one detected photon. The VLPC can do this with 99% accuracy. 相似文献
69.
Holger Friedrich Oliver Rogalla Ru¨diger Dillmann 《Journal of Intelligent Manufacturing》1998,9(2):119-127
Currently, an important topic of robotic research is the design and development of multi-agent robot systems (MASs). In these a number of autonomous robots cooperate and coordinate themselves in order to pursue given goals. The agents of an MAS not only have to work autonomously or in cooperation with other agents, but in dynamic, relatively unstructured environments. Therefore, the agents require agent-specific but flexible skills to cope with their tasks and the environment's variability. On the other hand, the actions to be performed by agents in an MAS have to meet certain requirements imposed by the MAS's structure. The representation of actions has to support planning, inter-agent communication, task negotiation etc. In this paper, we describe a method of combining the agent-specific nature of skills with the requirements for a general action knowledge representation inherent to MASs, by presenting elementary operations (EOs) that provide an appropriate interface. 相似文献
70.
This paper presents a strategy for the design and organization of materials for Web‐based instruction (WBI) founded upon cognitive modeling for the identification and organization of the major concepts in the domain of interest, based upon the Pathfinder paradigm. The original purpose of the Pathfinder paradigm was to model aspects of human semantic (associative) memory. A brief introduction to the Pathfinder paradigm is presented, and the rationale for its use in WBI is discussed. The development of this paradigm for WBI, in the context of eliciting and representing knowledge from domain experts, and its use in a pilot study is described. The domain used for the pilot study was the A* search algorithm, embedded within an introductory course in artificial intelligence. Assessment of the paradigm is also discussed, and preliminary methods are applied to the pilot study. 相似文献