4850818
Analysis of Weblog Link Structure - A Community Perspective
In this paper, we report a two level study on weblog link structures. At the micro level, we carried out an in-depth investigation of individual weblogs. Our goal was to obtain some preliminary understanding of the different types of links that might indicate underlying communities of bloggers. Complete and detailed link data was collected from eight weblogs followed by a variety of analyses. The result shows that both incoming and outgoings follow Zipf like distribution in terms of the sources of those links. These suggest clustering patterns (communities) within the whole blogspace. We also examine the temporal aspects of weblogs. The average life span of a weblog entry is fairly long in most of our sample cases. In addition, analysis on individual comment authors shows that in average, active comment authors maintain a rather long relationship with a certain weblog. It provides evidence that historical data may be useful in understanding weblog communities. On a larger scale, we developed a program to collect complete link data from large number of interconnected weblogs and performed cluster analysis on it. Communities with common topics are successfully extracted using those link data.
35187915
Conceptual Data Modelling in Database Design: Similarities and Differences between Expert and Novice Designers
Abstract This paper explores the similarities and differences between experts and novices engaged in a conceptual data modelling task, a critical part of overall database design, using data gathered in the form of think-aloud protocols. It develops a three-level process model of the subjects' behavior and the differentiated application of this model by experts and novices. The study found that the experts focused on generating a holistic understanding of the problem before developing the conceptual model. They were able to categorize problem descriptions into standard abstractions. The novices tended to have more errors in their solutions largely due to their inability to integrate the various parts of the problem description and map them into appropriate knowledge structures. The study also found that the expert and novice behavior was similar in terms of modelling facets like entity, identifier, descriptor and binary relationship, somewhat different in modelling ternary relationship, but quite different in the modelling of unary relationship and category. These findings are discussed in relation to the results of previous expert-novice studies in other domains.
18286129
Workflow Based Just-in-time Training
This paper focuses on the problem of information overload for newcomers in an organisation. We propose to address it by constructing a smart personal training assistant based upon workflow tools to drive temporal management of a just-intime workplace training system which will deliver a personalised and structured presentation of organisational documents.
3198534
Understanding Information Technology Complementarities Using an Augmented Endogenous Growth Framework
The complex relationships between information technology investments and organizational practices have been the focus of intensive research in recent years. The research focus appears to have shifted to investigating the effects of various organizational practices and their interactions with information technology capital. There also is emerging evidence of recent emphasis on organizational factors and a greater shift toward IT complementarities in which value addition is linked to combining complementary organizational practices with IT investments. In this paper we focus on the contributions of IT use and organizational practices and their interactions. We use firm-level data to extend previous studies in three ways: (1) by using a large sample covering 3,299 firms spanning 11 industries, (2) by focusing on a large number of organizational practices, and (3) by augmenting the endogenous growth accounting framework with a data mining technique. Our findings indicate that the set of interrelated organizational practices that complement positively to IT use is different from the set of practices hindering IT use. We conclude that IT complementary factors that positively affect productivity growth do not necessarily have a reverse effect when they are reduced or removed. It appears that some organizational factors have asymmetrical effects on growth.
17316572
Aligning Ontologies through Formal Concept Analysis
Abstract.Ontologies have been developed for a number of knowledge domains as di-verseasclinicalterminology,photocamerapartsandmicro-arraygeneexpressiondata.However,aninnatecharacteristicofthedevelopmentofontologiesisthattheyareoftencreatedbyindependentgroupsofexpertise,whichgeneratedthenecessityofmergingandaligningontologiescoveringoverlappingdomains.Manyalgorithmsandtoolshavebeenproposedformergingofontologies,butmostofthemdisregardthestructuralpropertiesofthesourceontologies,focusingmostlyonsyntacticanalysis.This article focuses on an alignment method for ontologies based on Formal ConceptAnalysis,adataanalysistechniquefoundedonlatticetheory. 1 Introduction IntheheartofSemanticWebinitiative,proposedbyTimBerners-lee[2,3],liestheideaofmachineprocessableinformation,suchthatautomatedagents,orsoftbots,couldscanthewebspaceforinformationwithaspeciﬂcmeaning.Nevertheless,theunderstandingofmeaninginWebpagesdesignedforhumansisnotaneasytaskforthepresentgenerationofsoftbotsandontologiescangreatlyassistinthisendeavour.Manyinitiativesaroundtheworldhavecreatedontologies.Someoftheseontologieswerecreatedforhighleveldescriptionoftheworld,whereasothersrepresentveryspeciﬂcsub-jects,likebreastcancer,forinstance.Sometimes,ontologiesdevelopedindependentlymayhavesomeoverlaps.TheforementionedBreastCancerOntology,forexample,mayhavecommonconceptsandrelationswithaGeneOntology.Theseoverlapsareveryimpor-tantfromthepointofviewofinformationintegration,becausethecommonontologicalentitieshavetobeidentiﬂedbeforeinformationcanbesuccessfullyintegrated.Forthisreason,mergeandalignmentofontologieshavereceivedsigniﬂcantattentionfromtheresearchcommunityinthelastsixyears.Theﬂrstimportantissueinmerge/alignmentofontologiesistherelationsymbol-meaning.Ontologiesareconstitutedofsymbols(entities)andrelationsbetweensymbols.However,inSemiotics[18]symbolshaveassociatedmeaning,whichlinksthemtotheirreferent
1126755
Creating Shared Information Spaces to Support Collaborative Design Work
The provision of computer support for collaborative work is a central concern for Information Systems (IS) research and practice. In this paper we present the details of an information flow study undertaken in the household division of a large European design and manufacturing company (Delta). The goal of the study was to elicit user requirements for a computer system to facilitate the collaborative work of new product design teams. These requirements form the basis for the design and development of a Web-based LIRÉ (Living Repository) prototype system, the functionalities, features, and rationale of which are discussed. We also present the results of the evaluation of LIRÉ by the users at Delta and our observations on enhancing the sophistication and usefulness of this class of system. A production version based on the prototype but using commercially available software is currently in use by the New Product Development group at Delta.
8707443
Transactional memory coherence and consistency
In this paper, we propose a new shared memory model: transactional memory coherence and consistency (TCC). TCC provides a model in which atomic transactions are always the basic unit of parallel work, communication, memory coherence, and memory reference consistency. TCC greatly simplifies parallel software by eliminating the need for synchronization using conventional locks and semaphores, along with their complexities. TCC hardware must combine all writes from each transaction region in a program into a single packet and broadcast this packet to the permanent shared memory state atomically as a large block. This simplifies the coherence hardware because it reduces the need for small, low-latency messages and completely eliminates the need for conventional snoopy cache coherence protocols, as multiple speculatively written versions of a cache line may safely coexist within the system. Meanwhile, automatic, hardware-controlled rollback of speculative transactions resolves any correctness violations that may occur when several processors attempt to read and write the same data simultaneously. The cost of this simplified scheme is higher interprocessor bandwidth. To explore the costs and benefits of TCC, we study the characteristics of an optimal transaction-based memory system, and examine how different design parameters could affect the performance of real systems. Across a spectrum of applications, the TCC model itself did not limit available parallelism. Most applications are easily divided into transactions requiring only small write buffers, on the order of 4-8 KB. The broadcast requirements of TCC are high, but are well within the capabilities of CMPs and small-scale SMPs with high-speed interconnects.
147709
Spacetime stereo: a unifying framework for depth from triangulation
Depth from triangulation has traditionally been investigated in a number of independent threads of research, with methods such as stereo, laser scanning, and coded structured light considered separately. We propose a common framework called spacetime stereo that unifies and generalizes many of these previous methods. To show the practical utility of the framework, we develop two new algorithms for depth estimation: depth from unstructured illumination change and depth estimation in dynamic scenes. Based on our analysis, we show that methods derived from the spacetime stereo framework can be used to recover depth in situations in which existing methods perform poorly.
2402326
Efficiently combining positions and normals for precise 3D geometry
Range scanning, manual 3D editing, and other modeling approaches can provide information about the geometry of surfaces in the form of either 3D positions (e.g., triangle meshes or range images) or orientations (normal maps or bump maps). We present an algorithm that combines these two kinds of estimates to produce a new surface that approximates both. Our formulation is linear, allowing it to operate efficiently on complex meshes commonly used in graphics. It also treats high-and low-frequency components separately, allowing it to optimally combine outputs from data sources such as stereo triangulation and photometric stereo, which have different error-vs.-frequency characteristics. We demonstrate the ability of our technique to both recover high-frequency details and avoid low-frequency bias, producing surfaces that are more widely applicable than position or orientation data alone.
31090559
The SSP: an example of high-assurance systems engineering
The SSP is a high assurance systems engineering effort spanning both hardware and software. Extensive design review, first principle design, n-version programming, program transformation, verification, and consistency checking are the techniques used to provide assurance in the correctness of the resulting system.
18888326
Analysis and recognition of walking movements
We present an approach for recognizing human walking movements using low-level motion regularities and constraints. Biomechanical features for classification are automatically extracted from video sequences of walkers. A multiplicative classification rule using statistical distances is then used to determine whether an unknown motion is consistent with normal walking patterns. Recognition results are shown distinguishing walking examples across multiple speeds from other nonwalking locomotions.