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101.
Pei-Lan Lei Gloria Yi-Ming Kao Sunny S.J. Lin Chuen-Tsai Sun 《Computers in human behavior》2009,25(6):1270-1279
Google Earth search function was used to study the impacts of small-scale spatial ability, large-scale environmental cognition, and geographical knowledge on new technology usage. The participants were 153 junior high students from central Taiwan. Geography grades served as indicators of prior knowledge, mental rotation and abstract reasoning skills as indicators of spatial ability, and sketch maps of school neighborhoods as indicators of environmental cognition (including landmark representation, intersection representation, and frame of reference). Lastly, the authors announced the landmarks searching worksheet and asked the participants to accomplish 16 familiar and unfamiliar landmark searching tasks using Google Earth with keyword search function disabled. The result showed the strongest predictor of landmark searching performance is ‘frame of reference’ in environmental cognition, followed by ‘mental rotation’ of spatial ability, ‘landmark representation’ of environmental cognition, and geographical knowledge. Google Earth landmark searches require complex cognitive processing; therefore, our conclusion is that GIS-supported image search activities give students good practice of active knowledge construction. 相似文献
102.
Muhammad F. Mysorewala Dan O. Popa Frank L. Lewis 《Journal of Intelligent and Robotic Systems》2009,54(4):535-565
The use of robotics in distributed monitoring applications requires wireless sensors that are deployed efficiently. A very
important aspect of sensor deployment includes positioning them for sampling at locations most likely to yield information
about the spatio-temporal field of interest, for instance, the spread of a forest fire. In this paper, we use mobile robots
(agents) that estimate the time-varying spread of wildfires using a distributed multi-scale adaptive sampling strategy. The
proposed parametric sampling algorithm, “EKF-NN-GAS” is based on neural networks, the extended Kalman filter (EKF), and greedy heuristics. It combines measurements arriving
at different times, taken at different scale lengths, such as from ground, airborne, and spaceborne observation platforms.
One of the advantages of our algorithm is the ability to incorporate robot localization uncertainty in addition to sensor
measurement and field parameter uncertainty into the same EKF model. We employ potential fields, generated naturally from
the estimated fire field distribution, in order to generate fire-safe trajectories that could be used to rescue vehicles and
personnel. The covariance of the EKF is used as a quantitative information measure for sampling locations most likely to yield
optimal information about the sampled field distribution. Neural net training is used infrequently to generate initial low
resolution estimates of the fire spread parameters. We present simulation and experimental results for reconstructing complex
spatio-temporal forest fire fields “truth models”, approximated by radial basis function (RBF) parameterizations. When compared
to a conventional raster scan approach, our algorithm shows a significant reduction in the time necessary to map the fire
field. 相似文献
103.
Meiling Liu Xiangnan Liu Menxin Wu Lufeng Li Lina Xiu 《Computers & Geosciences》2011,37(10):1642-1652
A generalized dynamic fuzzy neural network (GDFNN) was created to estimate heavy metal concentrations in rice by integrating spectral indices and environmental parameters. Hyperspectral data, environmental parameters, and heavy metal content were collected from field experiments with different levels of heavy metal pollution (Cu and Cd). Input variables used in the GDFNN model were derived from 10 variables acquired by gray relational analysis. The assessment models for Cd and Cu concentration employed five and six input variables, respectively. The results showed that the GDFNN for estimating Cu and Cd concentrations in rice performed well at prediction with a compact network structure using the training, validation, and testing sets (for Cu, fuzzy rules=9, R2 greater than 0.75, and RMSE less than 2.5; for Cd, fuzzy rules=9, R2 greater than 0.75, and RMSE less than 1.0). The final GDFNN model was then compared with a back-propagation (BP) neural network model, adaptive-network-based fuzzy interference systems (ANFIS), and a regression model. The accuracies of GDFNN model prediction were usually slightly better than those of the other three models. This demonstrates that the GDFNN model is more suitable for predicting heavy metal concentrations in rice. 相似文献
104.
Edzer Pebesma Dan CornfordGregoire Dubois Gerard B.M. HeuvelinkDionisis Hristopulos Jürgen PilzUlrich Stöhlker Gary MorinJon O. Skøien 《Computers & Geosciences》2011,37(3):343-352
INTAMAP is a Web Processing Service for the automatic spatial interpolation of measured point data. Requirements were (i) using open standards for spatial data such as developed in the context of the Open Geospatial Consortium (OGC), (ii) using a suitable environment for statistical modelling and computation, and (iii) producing an integrated, open source solution. The system couples an open-source Web Processing Service (developed by 52°North), accepting data in the form of standardised XML documents (conforming to the OGC Observations and Measurements standard) with a computing back-end realised in the R statistical environment. The probability distribution of interpolation errors is encoded with UncertML, a markup language designed to encode uncertain data. Automatic interpolation needs to be useful for a wide range of applications and the algorithms have been designed to cope with anisotropy, extreme values, and data with known error distributions. Besides a fully automatic mode, the system can be used with different levels of user control over the interpolation process. 相似文献
105.
Inside the adaptive enterprise: an information technology capabilities perspective on business process agility 总被引:3,自引:2,他引:1
Paul Patrick Tallon 《Information Technology and Management》2008,9(1):21-36
Recent innovations in utility computing, web services, and service-oriented architectures, combined with a growing array of
IT skills, have improved firms’ ability to be more agile in responding to change. Using the resource-based view of the firm,
prior research suggests that IT resources, in isolation, are unlikely to yield superior performance and so as firms try to
boost their agility, the question becomes how to configure IT resources to prepare for, or react to, change. In this paper,
we posit that managerial IT capabilities based on IT-business partnerships, strategic planning, and ex-post IT project analysis
lead to the development of technical IT capabilities associated with a flexible IT infrastructure which in turn drives agility
or a firm’s ability to react to change in its products and markets. Using data from matched surveys of IT and business executives
in 241 firms, we find that managerial and technical capabilities affect agility. In further testing, we reveal that in a stable
setting, technical IT capabilities are more important to agility than managerial IT capabilities, while in a dynamic setting,
the opposite is true. Thus, for firms operating in volatile markets, effective models of managerial IT governance are essential
for delivering superior agility or adaptiveness.
相似文献
Paul Patrick TallonEmail: |
106.
Eiman Kanjo Steve Benford Mark Paxton Alan Chamberlain Danae Stanton Fraser Dawn Woodgate David Crellin Adrain Woolard 《Personal and Ubiquitous Computing》2008,12(8):599-607
Mobile sensing and mapping applications are becoming more prevalent because sensing hardware is becoming more portable and
more affordable. However, most of the hardware uses small numbers of fixed sensors that report and share multiple sets of
environmental data which raises privacy concerns. Instead, these systems can be decentralized and managed by individuals in
their public and private spaces. This paper describes a robust system called MobGeoSens which enables individuals to monitor
their local environment (e.g. pollution and temperature) and their private spaces (e.g. activities and health) by using mobile
phones in their day to day life. The MobGeoSen is a combination of software components that facilitates the phone’s internal
sensing devices (e.g. microphone and camera) and external wireless sensors (e.g. data loggers and GPS receivers) for data
collection. It also adds a new dimension of spatial localization to the data collection process and provides the user with
both textual and spatial cartographic displays. While collecting the data, individuals can interactively add annotations and
photos which are automatically added and integrated in the visualization file/log. This makes it easy to visualize the data,
photos and annotations on a spatial and temporal visualization tool. In addition, the paper will present ways in which mobile
phones can be used as noise sensors using an on-device microphone. Finally, we present our experiences with school children
using the above mentioned system to measure their exposure to environmental pollution.
相似文献
Adrain WoolardEmail: |
107.
Gediminas Adomavicius Jesse C. Bockstedt Alok Gupta Robert J. Kauffman 《Information Technology and Management》2007,8(2):185-202
We propose a new conceptual model for understanding technology evolution that highlights dynamic and highly interdependent
relationships among multiple technologies. We argue that, instead of considering technologies in isolation, technology evolution
is best viewed as a dynamic system or ecosystem that includes a variety of interrelated technologies. By considering the interdependent nature of technology evolution, we
identify three roles that technologies play within a technology ecosystem. These roles are components, products and applications, and support and infrastructure. Technologies within an ecosystem interact through these roles and impact each others’ evolution. We also classify types
of interactions between technology roles, which we term paths of influence. We demonstrate the use of our proposed model through examples of wireless networking (Wi-Fi) technologies and a business
mini-case on the digital music industry.
相似文献
Robert J. KauffmanEmail: |
108.
Toxicoproteomics is the use of proteomic technologies to better understand environmental and genetic factors, toxic mechanisms, and modes of action in response to acute exposure to toxicants and in the long-term development of diseases caused or influenced by these exposures. Use of toxicoproteomic technologies to identify key biochemical pathways, mechanisms, and biomarkers of exposure and toxicity will decrease the uncertainties that are associated with human health risk assessments. This review provides an overview of toxicoproteomics from human health risk assessment perspectives. Key toxicoproteomic technologies such as 2-D gel-based proteomic methods and toxicoproteomic approaches are described, and examples of applications of these technologies and methodologies in the risk assessment context are presented. The discussion includes a focus on challenges and future directions. 相似文献
109.
110.
Mariya Pachman 《Computers & Education》2012,58(1):100-110
This study explores younger and older adults learning of MS Publisher functionalities from a multimedia tutorial. Twenty younger and twenty three older adults assigned to a redundant (experimental) or non-redundant (control) condition were taught how to create a greeting card, while the results of their learning were assessed with immediate and delayed performance measures. While younger learners benefited from a non-redundant condition, older learners exhibited an opposite trend. Redundant condition was beneficial for their performance efficiency on a set of a transfer tasks, and their troubleshooting performance during the delayed session. From a cognitive load perspective, using a redundant text along with an audio narration overloads learner’s working memory by placing more strain on the visual pathway and not providing any additional cognitive advantage. From an environmental support standpoint and decreased processing resources view of cognitive aging, providing additional representational support helps reducing the task demands for older adults and results in better learning. The results have cognitive and practical implications for the design of multimedia learning environments for older adults. 相似文献