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101.
Effects of Auditory Cues for Linear and Differential Magnification Methods on Visual Inspection Performance
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The unfavorable consequence of biased attention to peripheral objects was reported with the use of a newly proposed differential magnification method by the authors. Given the favorable influence of auditory cueing on attention orientation, this study investigated the effectiveness of auditory cues in directing participants’ attention from the peripheral to foveal areas of the differential magnifying lens for improving inspection performance. Thirty‐nine Chinese undergraduates performed a simulated inspection task using a particular magnification method (between‐participant factor). Three within‐participant factors of auditory cue interval, target difficulty, and magnification power were tested. Objective performance measures of speed and accuracy and subjective evaluation using NASA task load index were collected and analyzed. The results showed that positive effects of auditory cues were found for the differential magnification methods but not for the traditional linear magnification method. Significant effects of target difficulty and magnification power were also found. It was concluded that the aid of auditory cues, which did not share the same attentional resource with the visual inspection task, proved to be an appropriate reminder for the differential magnification methods to improve participants’ visual inspection performance. Attention should also be paid to selecting an appropriate auditory cue interval for search tasks of different target difficulties. The findings of this study have implications for the design of video magnifiers in the context of multimodal human–machine interfaces. 相似文献
102.
103.
Abstract Previous research shows that although collaboration technology can improve the exchange of information during team decision making, one of the challenges is that this better discussion often does not lead to better decisions. In this paper, we investigate the impact of individual information processing on team decision making. We investigated the effects of two types of collaboration technology when participants were either the member of a team majority or a team minority. There was little impact due to the majority/minority, but the use of collaboration technology that required users to categorize the comments they received from others resulted in increased information processing, which in turn led to better decisions and more satisfied participants. 相似文献
104.
Richmond VL Rayson MP Wilkinson DM Carter JM Blacker SD Nevill A Ross JD Moore S 《Ergonomics》2008,51(6):935-946
Since 2002, the Royal Air Force (RAF) has been working towards developing role-related physical tests for use as an operational fitness test (OFT). The purpose of this study was to establish reliability of the OFT (comprising four tests), investigate gym-based tests as predictors of performance and establish performance standards. Fifty-eight RAF personnel performed the OFT on three occasions. A separate cohort carried out fitness and anthropometric tests before performing the OFT, by way of establishing performance predictors. Documented evidence and views of an expert panel were used to determine OFT standards. Reliability ranged from moderate to good for three tests, with one test (Dig) showing poor reliability. The 95% limits of agreement for the prediction models ranged from good to poor (6.7-34.2%). The prediction models were not sufficiently accurate to estimate confidently OFT performance, but could be used as a guide to quantify likely outcome and training needs. 相似文献
105.
Decision support for network disruption mitigation 总被引:1,自引:0,他引:1
Our increasing reliance on networks of all types, coupled with their increasing vulnerability to disruption, makes it critical to better understand risks associated with natural disasters, terrorist attacks, and other incidents. However, choosing how to best protect, reinforce, and improve a network given a limited budget is a complex problem. We have developed an integrated approach that examines the effects of different network disruption scenarios for a variety of performance measures. The developed decision support methodology allows for comprehensive exploration of disruption impacts, statistically and visually, and facilitates examination of “what-if” planning scenarios. 相似文献
106.
Reconfigurable computing (RC) applications employing both microprocessors and FPGAs have potential for large speedup when compared with traditional (software) parallel applications. However, this potential is marred by the additional complexity of these dual-paradigm systems, making it difficult to identify performance bottlenecks and achieve desired performance. Performance analysis concepts and tools are well researched and widely available for traditional parallel applications but are lacking in RC, despite being of great importance due to the applications’ increased complexity. In this paper, we explore challenges and present new techniques in automated instrumentation, runtime measurement, and visualization of RC application behavior. We also present ideas for integration with conventional performance analysis tools to create a unified tool for RC applications as well as our initial framework for FPGA instrumentation and measurement. Results from a case study are provided using a prototype of this new tool. 相似文献
107.
Zhen He X. Sean Wang Byung Suk Lee Alan C. H. Ling 《Knowledge and Information Systems》2008,15(1):31-54
Recently, periodic pattern mining from time series data has been studied extensively. However, an interesting type of periodic
pattern, called partial periodic (PP) correlation in this paper, has not been investigated. An example of PP correlation is
that power consumption is high either on Monday or Tuesday but not on both days. In general, a PP correlation is a set of
offsets within a particular period such that the data at these offsets are correlated with a certain user-desired strength.
In the above example, the period is a week (7 days), and each day of the week is an offset of the period. PP correlations
can provide insightful knowledge about the time series and can be used for predicting future values. This paper introduces
an algorithm to mine time series for PP correlations based on the principal component analysis (PCA) method. Specifically,
given a period, the algorithm maps the time series data to data points in a multidimensional space, where the dimensions correspond
to the offsets within the period. A PP correlation is then equivalent to correlation of data when projected to a subset of
the dimensions. The algorithm discovers, with one sequential scan of data, all those PP correlations (called minimum PP correlations)
that are not unions of some other PP correlations. Experiments using both real and synthetic data sets show that the PCA-based
algorithm is highly efficient and effective in finding the minimum PP correlations.
Zhen He is a lecturer in the Department of Computer Science at La Trobe University. His main research areas are database systems
optimization, time series mining, wireless sensor networks, and XML information retrieval. Prior to joining La Trobe University,
he worked as a postdoctoral research associate in the University of Vermont. He holds Bachelors, Honors and Ph.D degrees in
Computer Science from the Australian National University.
X. Sean Wang received his Ph.D degree in Computer Science from the University of Southern California in 1992. He is currently the Dorothean
Chair Professor in Computer Science at the University of Vermont. He has published widely in the general area of databases
and information security, and was a recipient of the US National Science Foundation Research Initiation and CAREER awards.
His research interests include database systems, information security, data mining, and sensor data processing.
Byung Suk Lee is associate professor of Computer Science at the University of Vermont. His main research areas are database systems, data
modeling, and information retrieval. He held positions in industry and academia: Gold Star Electric, Bell Communications Research,
Datacom Global Communications, University of St. Thomas, and currently University of Vermont. He was also a visiting professor
at Dartmouth College and a participating guest at Lawrence Livermore National Laboratory. He served on international conferences
as a program committee member, a publicity chair, and a special session organizer, and also on US federal funding proposal
review panel. He holds a BS degree from Seoul National University, MS from Korea Advanced Institute of Science and Technology,
and Ph.D from Stanford University.
Alan C. H. Ling is an assistant professor at Department of Computer Science in University of Vermont. His research interests include combinatorial
design theory, coding theory, sequence designs, and applications of design theory. 相似文献
108.
Park-and-ride services are an important component of many public transportation systems in the United States. Locating park-and-ride facilities is an essential step when planning for these services. In this research we focus on three major siting/modeling concerns that need to be addressed when siting park-and-ride facilities: covering as much potential demand as possible, locating park-and-ride facilities as close as possible to major roadways, and siting such facilities in the context of an existing system. Unfortunately, existing models do not enable each of these concerns to be simultaneously addressed. This paper presents a multi-objective spatial optimization model for integrating these considerations. This model is applied for siting park-and-ride facilities in Columbus, Ohio. Application results show the usefulness of the developed model in supporting transit planning in an urban region. 相似文献
109.
Guided by the Uses and Gratifications (U&G) perspective, this study examined the influence of unwillingness to communicate, loneliness, Internet-use motives, and Internet (CMC) use and interaction (amount and types of use and self-disclosure) in online communication satisfaction and online relationship closeness. There were 261 participants in this study. Overall, participants who perceived their face-to-face communication to be rewarding, used CMC for self-fulfillment, and disclosed their personal feelings to others tended to feel close to their online partners. Moreover, those who used the Internet for purposes of self-fulfillment and affection and intended to disclose their feelings to others felt satisfied with their online communication. The associations among the constructs extend our knowledge of the U&G theoretical model, how and why people communicate interpersonally in CMC settings, and the influence of individual differences on CMC for relational communication. 相似文献
110.
Transfer in variable-reward hierarchical reinforcement learning 总被引:2,自引:1,他引:1
Transfer learning seeks to leverage previously learned tasks to achieve faster learning in a new task. In this paper, we consider
transfer learning in the context of related but distinct Reinforcement Learning (RL) problems. In particular, our RL problems are derived from Semi-Markov Decision Processes (SMDPs) that share the same
transition dynamics but have different reward functions that are linear in a set of reward features. We formally define the
transfer learning problem in the context of RL as learning an efficient algorithm to solve any SMDP drawn from a fixed distribution
after experiencing a finite number of them. Furthermore, we introduce an online algorithm to solve this problem, Variable-Reward
Reinforcement Learning (VRRL), that compactly stores the optimal value functions for several SMDPs, and uses them to optimally
initialize the value function for a new SMDP. We generalize our method to a hierarchical RL setting where the different SMDPs
share the same task hierarchy. Our experimental results in a simplified real-time strategy domain show that significant transfer
learning occurs in both flat and hierarchical settings. Transfer is especially effective in the hierarchical setting where
the overall value functions are decomposed into subtask value functions which are more widely amenable to transfer across
different SMDPs. 相似文献