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1.
Moving point object data can be analyzed through the discovery of patterns in trajectories. We consider the computational
efficiency of detecting four such spatio-temporal patterns, namely flock, leadership, convergence, and encounter, as defined
by Laube et al., Finding REMO—detecting relative motion patterns in geospatial lifelines, 201–214, ( 2004). These patterns are large enough subgroups of the moving point objects that exhibit similar movement in the sense of direction,
heading for the same location, and/or proximity. By the use of techniques from computational geometry, including approximation
algorithms, we improve the running time bounds of existing algorithms to detect these patterns.
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2.
This paper describes security and privacy issues for multimedia database management systems. Multimedia data includes text,
images, audio and video. It describes access control for multimedia database management systems and describes security policies
and security architectures for such systems. Privacy problems that result from multimedia data mining are also discussed.
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3.
In the last few years there has been an increasing interest for a novel category of access control models known as location-based
or spatially-aware role-based access control (RBAC) models. Those models advance classical RBAC models in that they regulate
the access to sensitive resources based on the position of mobile users. An issue that has not yet been investigated is how
to administer spatially-aware access control policies. In this paper we introduce GEO-RBAC Admin, the administration model
for the location-based GEO-RBAC model. We discuss the concepts underlying such administrative model and present a language
for the specification of GEO-RBAC policies.
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4.
Recent growth of the geospatial information on the web has made it possible to easily access a wide variety of spatial data.
The ability to combine various sets of geospatial data into a single composite dataset has been one of central issues of modern
geographic information processing. By conflating diverse spatial datasets, one can support a rich set of queries that could
have not been answered given any of these sets in isolation. However, automatically conflating geospatial data from different
data sources remains a challenging task. This is because geospatial data obtained from various data sources may have different
projections, different accuracy levels and different formats (e.g., raster or vector format), thus resulting in various positional
inconsistencies. Most of the existing algorithms only deal with vector to vector data conflation or require human intervention
to accomplish vector data to imagery conflation. In this paper, we describe a novel geospatial data fusion approach, named
AMS-Conflation, which achieves automatic vector to imagery conflation. We describe an efficient technique to automatically
generate control point pairs from the orthoimagery and vector data by exploiting the information from the vector data to perform
localized image processing on the orthoimagery. We also evaluate a filtering technique to automatically eliminate inaccurate
pairs from the generated control points. We show that these conflation techniques can automatically align the roads in orthoimagery,
such that 75% of the conflated roads are within 3.6 meters from the real road axes compared to 35% for the original vector
data for partial areas of the county of St. Louis, MO.
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5.
We present a study of using camera-phones and visual-tags to access mobile services. Firstly, a user-experience study is described in which participants were both observed learning to interact with a prototype mobile service and interviewed
about their experiences. Secondly, a pointing-device task is presented in which quantitative data was gathered regarding the speed and accuracy with which participants aimed and clicked
on visual-tags using camera-phones. We found that participants’ attitudes to visual-tag-based applications were broadly positive,
although they had several important reservations about camera-phone technology more generally. Data from our pointing-device
task demonstrated that novice users were able to aim and click on visual-tags quickly (well under 3 s per pointing-device
trial on average) and accurately (almost all meeting our defined speed/accuracy tradeoff of 6% error-rate). Based on our findings,
design lessons for camera-phone and visual-tag applications are presented.
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6.
Vector data and in particular road networks are being queried, hosted and processed in many application domains such as in
mobile computing. Many client systems such as PDAs would prefer to receive the query results in unrasterized format without
introducing an overhead on overall system performance and result size. While several general vector data compression schemes
have been studied by different communities, we propose a novel approach in vector data compression which is easily integrated
within a geospatial query processing system. It uses line aggregation to reduce the number of relevant tuples and Huffman
compression to achieve a multi-resolution compressed representation of a road network database. Our experiments performed
on an end-to-end prototype verify that our approach exhibits fast query processing on both client and server sides as well
as high compression ratio.
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7.
This paper describes the simulated car racing competition that was arranged as part of the 2007 IEEE Congress on Evolutionary
Computation. Both the game that was used as the domain for the competition, the controllers submitted as entries to the competition
and its results are presented. With this paper, we hope to provide some insight into the efficacy of various computational
intelligence methods on a well-defined game task, as well as an example of one way of running a competition. In the process,
we provide a set of reference results for those who wish to use the simplerace game to benchmark their own algorithms. The paper is co-authored by the organizers and participants of the competition.
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8.
Quantitative usability requirements are a critical but challenging, and hence an often neglected aspect of a usability engineering process. A case study is described where quantitative usability requirements played a key role in the development of a new user interface of a mobile phone. Within the practical constraints of the project, existing methods for determining usability requirements and evaluating the extent to which these are met, could not be applied as such, therefore tailored methods had to be developed. These methods and their applications are discussed. 相似文献
9.
In the near future, our life will normally be surrounded with fairly complicated artifacts, enabled by the autonomous robot
and brain–machine interface technologies. In this paper, we argue that what we call the responsibility flaw problem and the
inappropriate use problem need to be overcome in order for us to benefit from complicated artifacts. In order to solve these
problems, we propose an approach to endowing artifacts with an ability of socially communicating with other agents based on
the artifact-as-a-half-mirror metaphor. The idea is to have future artifacts behave according to the hybrid intention composed
of the owner’s intention and the social rules. We outline the approach and discuss its feasibility together with preliminary
work.
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10.
Support vector machines (SVMs) have been promising methods for classification and regression analysis due to their solid mathematical
foundations, which include two desirable properties: margin maximization and nonlinear classification using kernels. However,
despite these prominent properties, SVMs are usually not chosen for large-scale data mining problems because their training
complexity is highly dependent on the data set size. Unlike traditional pattern recognition and machine learning, real-world
data mining applications often involve huge numbers of data records. Thus it is too expensive to perform multiple scans on
the entire data set, and it is also infeasible to put the data set in memory. This paper presents a method, Clustering-Based SVM (CB-SVM), that maximizes the SVM performance for very large data sets given a limited amount of resource, e.g., memory. CB-SVM applies
a hierarchical micro-clustering algorithm that scans the entire data set only once to provide an SVM with high quality samples.
These samples carry statistical summaries of the data and maximize the benefit of learning. Our analyses show that the training
complexity of CB-SVM is quadratically dependent on the number of support vectors, which is usually much less than that of
the entire data set. Our experiments on synthetic and real-world data sets show that CB-SVM is highly scalable for very large
data sets and very accurate in terms of classification.
A preliminary version of the paper, “ Classifying Large Data Sets Using SVM with Hierarchical Clusters”, by H. Yu, J. Yang, and J. Han, appeared in Proc. 2003 Int. Conf. on Knowledge Discovery in Databases (KDD'03), Washington, DC, August 2003. However, this submission has substantially extended the previous paper and contains new and
major-value added technical contribution in comparison with the conference publication.
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11.
Nowadays data mining plays an important role in decision making. Since many organizations do not possess the in-house expertise
of data mining, it is beneficial to outsource data mining tasks to external service providers. However, most organizations
hesitate to do so due to the concern of loss of business intelligence and customer privacy. In this paper, we present a Bloom
filter based solution to enable organizations to outsource their tasks of mining association rules, at the same time, protect
their business intelligence and customer privacy. Our approach can achieve high precision in data mining by trading-off the
storage requirement.
This research was supported by the USA National Science Foundation Grants CCR-0310974 and IIS-0546027.
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12.
In this paper web–based system user interface hybrid recommendation method based on the ant colony metaphor is presented.
We apply the ontology–based user and user interface modeling. The user model is represented as a tuple and user interface
model is represented by a set of connected nodes, what enables suitable user interface design, an interface personalization
and recommendation. The recommendation is performed using ant colony metaphor for selection the most optimal path in the user
interface graph that specifies the user interface parameters for the specified user.
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13.
Listening to music on personal, digital devices whilst mobile is an enjoyable, everyday activity. We explore a scheme for
exploiting this practice to immerse listeners in navigation cues. Our prototype, ONTRACK, continuously adapts audio, modifying
the spatial balance and volume to lead listeners to their target destination. First we report on an initial lab-based evaluation
that demonstrated the approach’s efficacy: users were able to complete tasks within a reasonable time and their subjective
feedback was positive. Encouraged by these results we constructed a handheld prototype. Here, we discuss this implementation
and the results of field-trials. These indicate that even with a low-fidelity realisation of the concept, users can quite
effectively navigate complicated routes.
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14.
The complexity of group dynamics occurring in small group interactions often hinders the performance of teams. The availability
of rich multimodal information about what is going on during the meeting makes it possible to explore the possibility of providing
support to dysfunctional teams from facilitation to training sessions addressing both the individuals and the group as a whole.
A necessary step in this direction is that of capturing and understanding group dynamics. In this paper, we discuss a particular
scenario, in which meeting participants receive multimedia feedback on their relational behaviour, as a first step towards
increasing self-awareness. We describe the background and the motivation for a coding scheme for annotating meeting recordings
partially inspired by the Bales’ Interaction Process Analysis. This coding scheme was aimed at identifying suitable observable
behavioural sequences. The study is complemented with an experimental investigation on the acceptability of such a service.
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15.
The paper reflects on the unique experience of social and technological development in Lithuania since the regaining of independence
as a newly reshaped society constructing a distinctive competitive IST-based model at global level. This has presented Lithuanian
pattern of how to integrate different experiences and relations between generations in implementing complex information society
approaches. The resulting programme in general is linked to the Lisbon objectives of the European Union. The experience of
transitional countries in Europe, each different but facing some common problems, may be useful to developing countries in
Africa.
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16.
Awareness systems have attracted significant research interest for their potential to support interpersonal relationships.
Investigations of awareness systems for the domestic environment have suggested that such systems can help individuals stay
in touch with dear friends or family and provide affective benefits to their users. Our research provides empirical evidence
to refine and substantiate such suggestions. We report our experience with designing and evaluating the ASTRA awareness system,
for connecting households and mobile family members. We introduce the concept of connectedness and its measurement through
the Affective Benefits and Costs of communication questionnaire (ABC-Q). We inform results that testify the benefits of sharing
experiences at the moment they happen without interrupting potential receivers. Finally, we document the role that lightweight,
picture-based communication can play in the range of communication media available.
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17.
In this paper we present an application fostering the integration and interoperability of computational lexicons, focusing
on the particular case of mutual linking and cross-lingual enrichment of two wordnets, the ItalWordNet and Sinica BOW lexicons.
This is intended as a case-study investigating the needs and requirements of semi-automatic integration and interoperability
of lexical resources, in the view of developing a prototype web application to support the GlobalWordNet Grid initiative.
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18.
We introduce a system for sensing complex social systems with data collected from 100 mobile phones over the course of 9 months.
We demonstrate the ability to use standard Bluetooth-enabled mobile telephones to measure information access and use in different
contexts, recognize social patterns in daily user activity, infer relationships, identify socially significant locations,
and model organizational rhythms.
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19.
We present XFlavor, a framework for providing XML representation of multimedia data. XFlavor can be used to convert multimedia
data back and forth between binary and XML representations. Compared to bitstreams, XML documents are easier to access and
manipulate, and consequently, the development of multimedia processing software is greatly facilitated, as one generic XML
parser can be used to read and write different types of data in XML form.
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20.
There are only a few ethical regulations that deal explicitly with robots, in contrast to a vast number of regulations, which
may be applied. We will focus on ethical issues with regard to “responsibility and autonomous robots”, “machines as a replacement
for humans”, and “tele-presence”. Furthermore we will examine examples from special fields of application (medicine and healthcare,
armed forces, and entertainment). We do not claim to present a complete list of ethical issue nor of regulations in the field
of robotics, but we will demonstrate that there are legal challenges with regard to these issues.
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