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61.
Ozgur Sinanoglu Mohammed Al-Mulla Noora A. Shunaiber and Alex Orailoglu Member IEEE 《计算机科学技术学报》2009,24(5):939-948
Ensuring a high manufacturing test quality of an integrated electronic circuit mandates the application of a large volume
test set. Even if the test data can be fit into the memory of an external tester, the consequent increase in test application
time reflects into elevated production costs. Test data compression solutions have been proposed to address the test time
and data volume problem by storing and delivering the test data in a compressed format, and subsequently by expanding the
data on-chip. In this paper, we propose a scan cell positioning methodology that accompanies a compression technique in order
to boost the compression ratio, and squash the test data even further. While we present the application of the proposed approach
in conjunction with the fan-out based decompression architecture, this approach can be extended for application along with
other compression solutions as well. The experimental results also confirm the compression enhancement of the proposed methodology. 相似文献
62.
Dianne Cyr Milena Head Alex Ivanov 《International journal of human-computer studies》2009,67(10):850-869
Novel applications of website interactivity are important to attract and retain online users. In this empirical study five designs for interactivity are examined using different web-poll interfaces. The goal of the investigation is to examine perceived interactivity in a model which includes most commonly tested cognitive elements such as efficiency and effectiveness, but augments this model with the inclusion of a cognitive–affective element for trust, and an affective element of enjoyment. More specifically, a model is created to validate the relationship of perceived interactivity (comprised of user control, user connectedness, and responsiveness of the web-poll application) to efficiency, effectiveness, trust and enjoyment, of the website. In turn, efficiency, effectiveness, trust, and enjoyment are tested for their influence on user behavioral intentions for e-loyalty. All relationships in the model are supported. In addition, exploratory evaluation of qualitative comments is conducted to investigate additional insights between the five web-poll treatments in this investigation. The research confirms the complexity of a model in which cognitive, cognitive–affective and affective elements are present, and advances knowledge on the consequences of perceived interactivity. In additional to theoretical advancements, the research has merit for web designers and online marketers regarding how to enhance interactive online web applications. 相似文献
63.
Delay- and Disruption-Tolerant Networking 总被引:3,自引:0,他引:3
Delay- and disruption-tolerant networking (DTN) grew out of attempts to develop an Interplanetary Internet but has evolved into an active area of networking research, with applications in space networking, military tactical networking, and networking for various challenged communities. The DTN Research Group provides an open forum in which DTN researchers and developers can collaborate to further develop this experimental technology. 相似文献
64.
Hierarchical classification of protein function with ensembles of rules and particle swarm optimisation 总被引:1,自引:1,他引:0
Nicholas Holden Alex A. Freitas 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(3):259-272
This paper focuses on hierarchical classification problems where the classes to be predicted are organized in the form of
a tree. The standard top-down divide and conquer approach for hierarchical classification consists of building a hierarchy
of classifiers where a classifier is built for each internal (non-leaf) node in the class tree. Each classifier discriminates
only between its child classes. After the tree of classifiers is built, the system uses them to classify test examples one
class level at a time, so that when the example is assigned a class at a given level, only the child classes need to be considered
at the next level. This approach has the drawback that, if a test example is misclassified at a certain class level, it will
be misclassified at deeper levels too. In this paper we propose hierarchical classification methods to mitigate this drawback.
More precisely, we propose a method called hierarchical ensemble of hierarchical rule sets (HEHRS), where different ensembles
are built at different levels in the class tree and each ensemble consists of different rule sets built from training examples
at different levels of the class tree. We also use a particle swarm optimisation (PSO) algorithm to optimise the rule weights
used by HEHRS to combine the predictions of different rules into a class to be assigned to a given test example. In addition,
we propose a variant of a method to mitigate the aforementioned drawback of top-down classification. These three types of
methods are compared against the standard top-down hierarchical classification method in six challenging bioinformatics datasets,
involving the prediction of protein function. Overall HEHRS with the rule weights optimised by the PSO algorithm obtains the
best predictive accuracy out of the four types of hierarchical classification method. 相似文献
65.
Wireless sensor networks are increasingly seen as a solution to the problem of performing continuous wide-area monitoring in many environmental, security, and military scenarios. The distributed nature of such networks and the autonomous behavior expected of them present many novel challenges. In this article, the authors argue that a new synthesis of electronic engineering and agent technology is required to address these challenges, and they describe three examples where this synthesis has succeeded. In more detail, they describe how these novel approaches address the need for communication and computationally efficient decentralized algorithms to coordinate the behavior of physically distributed sensors, how they enable the real-world deployment of sensor agent platforms in the field, and finally, how they facilitate the development of intelligent agents that can autonomously acquire data from these networks and perform information processing tasks such as fusion, inference, and prediction. 相似文献
66.
Alex W. Wardrop 《Networks and Spatial Economics》2009,9(1):123-143
The functions of Australia’s railways are divided between the delivery of suburban passenger railway services, long distance
general and intermodal freight services and regional bulk commodity haulage. There is a national interest in the efficient
carriage of export freight flows because Australia is a major trading nation. Australia’s railways are expected play their
part in hauling export commodities. Unsurprisingly, there are conflicting demands on these railways. Hence, universities,
and the industry itself, are directing research and investigation effort into policy, planning, engineering, operational and
human factors matters. A question which then arises is what means could be used to analyse the problems identified during
this research and investigation. This paper is thus concerned with the inter-relationships between the planning, engineering
and operations of railways in Australia. It identifies four areas of analysis associated with the planning and development
of railway infrastructure and operations. It then discusses a range of analytical tools which could be applied to different
components of these analytical areas and critiques their appropriateness from an Australian perspective. Having made this
assessment, the paper uses a recent Australian case study to show how analytical tools could be used and what lessons might
be learnt from the process.
Figure Use of Railway Analysis Tools from an Australian Perspective
相似文献
Alex W. WardropEmail: |
67.
Ioannis Pogkas Vassil Kriakov Zhongqiang Chen Alex Delis 《Peer-to-Peer Networking and Applications》2009,2(1):37-59
To address the two most critical issues in P2P file-sharing systems: efficient information discovery and authentic data acquisition, we propose a Gnutella-like file-sharing protocol termed Adaptive Gnutella Protocol (AGP) that not only improves the querying efficiency in a P2P network but also enhances the quality of search results at the same time. The reputation scheme in the proposed AGP evaluates the credibility of peers based on their contributions to P2P services and subsequently clusters nodes together according to their reputation and shared content, essentially transforming
the P2P overlay network into a topology with collaborative and reputed nodes as its core. By detecting malicious peers as well as
free-riders and eventually pushing them to the edge of the overlay network, our AGP propagates search queries mainly within the core of the topology, accelerating the information discovery process. Furthermore,
the clustering of nodes based on authentic and similar content in our AGP also improves the quality of search results. We have implemented the AGP with the PeerSim simulation engine and conducted thorough experiments on diverse network topologies and various mixtures of honest/dishonest
nodes to demonstrate improvements in topology transformation, query efficiency, and search quality by our AGP.
Ioannis Pogkas received his BS in Computer Science in 2007 and is currently pursuing postgraduate studies at the Department of Informatics and Telecommunications of the Univesrity of Athens. His research interests focus on search, reputation andtopology adaptation mechanisms in peer-to-peer networks. He is also interested in embedded and operating systems. Vassil Kriakov received his B.S. and M.S. from Polytechnic University in 2001 and is now completing his doctoral studies at the Polytechnic Institute of New York University (NYU-Poly). His PhD research has been partially sponsored by a US Department of Education GAANN Graduate Fellowship. His research interests include distributed spatio-temporal data indexing, correlations in high-frequency data streams, and data management in grid and peer-to-peer networks. Zhongqiang Chen is a senior software engineer at Yahoo! He holds a PhD in Computer Science and MS degrees in both Computer Science and Electrical Engineering all from Polytechnic University in Brooklyn, NY. He is a Computer Engineering MS and BS graduate of Tsinghua University, Beijing, P.R. China. He is interested in network security, information retrieval, and distributed computing and is the recipient of the 2004 Wilkes Award for outstanding paper contribution in The Computer Journal. Alex Delis is a Professor of Computer Science at the University of Athens. He holds a PhD and an MS from the University of Maryland College Park as well as a Diploma in Computer Engineering from the University of Patras. His research interests are in distributed computing systems, networked information systems, databases and information security. He is a member of IEEE Computer Society, the ACM and the Technical Chamber of Greece. 相似文献
Alex DelisEmail: |
Ioannis Pogkas received his BS in Computer Science in 2007 and is currently pursuing postgraduate studies at the Department of Informatics and Telecommunications of the Univesrity of Athens. His research interests focus on search, reputation andtopology adaptation mechanisms in peer-to-peer networks. He is also interested in embedded and operating systems. Vassil Kriakov received his B.S. and M.S. from Polytechnic University in 2001 and is now completing his doctoral studies at the Polytechnic Institute of New York University (NYU-Poly). His PhD research has been partially sponsored by a US Department of Education GAANN Graduate Fellowship. His research interests include distributed spatio-temporal data indexing, correlations in high-frequency data streams, and data management in grid and peer-to-peer networks. Zhongqiang Chen is a senior software engineer at Yahoo! He holds a PhD in Computer Science and MS degrees in both Computer Science and Electrical Engineering all from Polytechnic University in Brooklyn, NY. He is a Computer Engineering MS and BS graduate of Tsinghua University, Beijing, P.R. China. He is interested in network security, information retrieval, and distributed computing and is the recipient of the 2004 Wilkes Award for outstanding paper contribution in The Computer Journal. Alex Delis is a Professor of Computer Science at the University of Athens. He holds a PhD and an MS from the University of Maryland College Park as well as a Diploma in Computer Engineering from the University of Patras. His research interests are in distributed computing systems, networked information systems, databases and information security. He is a member of IEEE Computer Society, the ACM and the Technical Chamber of Greece. 相似文献
68.
Li Wei Joseph Raj Alex Noel Tjahjadi Tardi Zhuang Zhemin 《Applied Intelligence》2022,52(13):15164-15176
Applied Intelligence - The retina is one of the most developed sensing organs in the human body. However, the knowledge on the coding and decoding of the retinal neurons are still rather limited.... 相似文献
69.
70.
Image variability that is impossible or difficult to restore by intra-image processing, such as the variability caused by occlusions, significantly reduces the performance of image-recognition methods. To address this issue, we propose that the pixels associated with large distances obtained by inter-image pixel-by-pixels comparisons should be considered as inter-image outliers and should be removed from the similarity calculation used for the image classification. When this method is combined with the template-matching method for image recognition, it leads to state-of-the-art recognition performance: 91% with AR database that includes occluded face images, 90% with PUT database that includes pose variations of face images and 100% with EYale B database that includes images with large illumination variation. 相似文献