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1.
There are several data based methods in the field of artificial intelligence which are nowadays frequently used for analyzing
classification problems in the context of medical applications. As we show in this paper, the application of enhanced evolutionary
computation techniques to classification problems has the potential to evolve classifiers of even higher quality than those
trained by standard machine learning methods. On the basis of five medical benchmark classification problems taken from the
UCI repository as well as the Melanoma data set (prepared by members of the Department of Dermatology of the Medical University Vienna) we document that the enhanced
genetic programming approach presented here is able to produce comparable or even better results than linear modeling methods,
artificial neural networks, kNN classification, support vector machines and also various genetic programming approaches.
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2.
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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3.
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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4.
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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5.
A category of Distributed Real-Time Systems (DRTS) that has multiprocessor pipeline architecture is increasingly used. The
key challenge of such systems is to guarantee the end-to-end deadlines of aperiodic tasks. This paper proposes an end-to-end
deadline control model, called Linear Quadratic Stochastic Optimal Control Model (LQ-SOCM), which features a distributed feedback
control that dynamically enforces the desired performance. The control system considers the aperiodic task arrivals and execution
times’ variation as the two external factors of the system unpredictability. LQ-SOCM uses discrete time state space equation
to describe the real-time computing system. Then, in the actuator design, a continuous manner is adopted to deal with discrete
QoS (Quality of Service) adaptation. Finally, experiments demonstrate that the system is globally stable and can statistically
provide the end-to-end deadline guarantee for aperiodic tasks. At the same time, LQ-SOCM is capable of effectively improving
the system throughput.
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6.
3D computer graphics have been an important feature in games development since it was first introduced in the early 80s and
there is no doubt that 3D based content is often viewed as more attractive in games than the more abstract 2D graphics. Many
games publishers are keen to leverage their success in the console market into the mobile phone platform. However, the resource
constraints of mobile phones and the fragmented nature of the environment present considerable challenges for games developers.
In this paper we consider some of the current constraints together with current and, probable, future developments both in
the software and hardware of mobile phones. As part of this process we benchmark some of the latest and most prevalent software
and hardware devices to ascertain both the quality of the graphics produced and the effects upon battery life. Whilst our
test results highlight that the current market does indeed present challenges, our research into the future developments highlights
the fact we are approaching greater standardization, which will be an important factor for the successful development of 3D
mobile games.
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7.
This paper presents an application of the quaternion Fourier transform for the preprocessing for neural-computing. In a new
way the 1D acoustic signals of French spoken words are represented as 2D signals in the frequency and time domain. These kind
of images are then convolved in the quaternion Fourier domain with a quaternion Gabor filter for the extraction of features.
This approach allows to greatly reduce the dimension of the feature vector. Two methods of feature extraction are tested.
The features vectors were used for the training of a simple MLP, a TDNN and a system of neural experts. The improvement in
the classification rate of the neural network classifiers are very encouraging which amply justify the preprocessing in the
quaternion frequency domain. This work also suggests the application of the quaternion Fourier transform for other image processing
tasks.
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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.
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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10.
A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have
been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal
model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO’s temporal
schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO’s
temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query
performance on feature history by removing topological comparison during query process. Further, a prototype system has been
developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of
temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure.
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11.
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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12.
We present an algorithmic growth process that is an extension of Lindenmayer’s Map L-systems. This growth process relies upon
a set of rewrite rules, a map axiom and a geometric interpreter which is integrated with a 3D simulated environment. The outcome
of the growth process is a digital surface in 3D space which has “grown” within and in response to its environment. We have
developed a complementary evolutionary algorithm that is able to take over the task of generating the rewrite rules set for
a growth process. Using a quantitative multi-objective fitness function that evaluates a variety of surface properties, the
integrated system (evolutionary algorithm and growth process) can explore and generate diverse and interesting surfaces with
a resemblance of organic form. The algorithms have been implemented to create a design tool for architects called Genr8.
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13.
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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14.
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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15.
This paper addresses the possibility of measuring perceived usability in an absolute way. It studies the impact of the nature
of the tasks performed in perceived software usability evaluation, using for this purpose the subjective evaluation of an
application’s performance via the Software Usability Measurement Inventory (SUMI). The paper reports on the post-hoc analysis
of data from a productivity study for testing the effect of changes in the graphical user interface (GUI) of a market leading
drafting application. Even though one would expect similar evaluations of an application’s usability for same releases, the
analysis reveals that the output of this subjective appreciation is context sensitive and therefore mediated by the research
design. Our study unmasked a significant interaction between the nature of the tasks used for the usability evaluation and
how users evaluate the performance of this application. This interaction challenges the concept of absolute benchmarking in
subjective usability evaluation, as some software evaluation methods aspire to provide, since subjective measurement of software
quality will be affected most likely by the nature of the testing materials used for the evaluation.
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16.
This paper proposes an appearance generative mixture model based on key frames for meanshift tracking. Meanshift tracking
algorithm tracks an object by maximizing the similarity between the histogram in tracking window and a static histogram acquired
at the beginning of tracking. The tracking therefore could fail if the appearance of the object varies substantially. In this
paper, we assume the key appearances of the object can be acquired before tracking and the manifold of the object appearance
can be approximated by piece-wise linear combination of these key appearances in histogram space. The generative process is
described by a Bayesian graphical model. An Online EM algorithm is proposed to estimate the model parameters from the observed
histogram in the tracking window and to update the appearance histogram. We applied this approach to track human head motion
and to infer the head pose simultaneously in videos. Experiments verify that our online histogram generative model constrained
by key appearance histograms alleviates the drifting problem often encountered in tracking with online updating, that the
enhanced meanshift algorithm is capable of tracking object of varying appearances more robustly and accurately, and that our
tracking algorithm can infer additional information such as the object poses.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
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17.
In this paper, we present an Inverse Multi-Objective Robust Evolutionary (IMORE) design methodology that handles the presence
of uncertainty without making assumptions about the uncertainty structure. We model the clustering of uncertain events in
families of nested sets using a multi-level optimization search. To reduce the high computational costs of the proposed methodology
we proposed schemes for (1) adapting the step-size in estimating the uncertainty, and (2) trimming down the number of calls
to the objective function in the nested search. Both offline and online adaptation strategies are considered in conjunction
with the IMORE design algorithm. Design of Experiments (DOE) approaches further reduce the number of objective function calls
in the online adaptive IMORE algorithm. Empirical studies conducted on a series of test functions having diverse complexities
show that the proposed algorithms converge to a set of Pareto-optimal design solutions with non-dominated nominal and robustness
performances efficiently.
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18.
In this paper we propose MicrelEye, a wireless video node for cooperative distributed video processing applications that involve
image classification. The node is equipped with a low-cost VGA CMOS image sensor, a reconfigurable processing engine (FPGA,
Microcontroller, SRAM) and a Bluetooth 100-m transceiver. It has a size of few cubic centimeters and its typical power consumption
is approximately ten times less than that of typical commercial DSP-based solutions. As regards classification, a highly optimized
hardware-oriented support vector machine-like (SVM-like) algorithm called ERSVM is proposed and implemented. We describe our
hardware and software architecture, its performance and power characteristics. The case study considered in this paper is
people detection. The obtained results suggest that the present technology allows for the design of simple intelligent video
nodes capable of performing classification tasks locally.
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19.
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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20.
Classic task models for real-time systems focus on execution windows expressing earliest start times and deadlines of tasks
for feasibility. Only within these windows the execution of tasks is feasible, and it is considered of uniform utility.
Some tasks, however, have target demands in addition: a task should preferably execute at a specific target point within its execution window, but can execute around
this point, albeit at lower utility. Examples of such applications include control and media processing.
In this paper, we present a task model based on a gravitational analogy to address these issues. Tasks are considered as massive
bobs hanging on a pendulum: a single task, left to itself, will execute at the bottom, the target point. If a force, such
as the weight of other tasks, is applied, it can be shifted around this point. Thus, tasks’ importance and their utility around
target points can be expressed. Since the execution of a task cannot be mapped to a point in time, the model allows tasks
to express an arbitrary point with its execution to represent the whole execution. This point is called the anchor point.
Moreover, we show an example of a scheduling algorithm for this model which finds an approximation to the best compromise
of tasks’ interests based on the equilibrium state of a pendulum. Nonetheless, this task model is not restricted to a particular
scheduling algorithm.
Results from a simulation study show the effectiveness of the approach.
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