The foundations of a theory-aware authoring tool for CSCL design

One of the most useful ways to enhance collaboration is to create scenarios where learners are able to interact more effectively. Nevertheless, the design of pedagogically sound and well-thought-out collaborative learning scenarios is a complex issue. This is due to the context of group learning where the synergy among learners’ interactions affects learning processes and, hence, the learning outcome. Although many advances have been made to support the designing of collaborative learning scenarios through technology, a more systematic approach is lacking. With the limitations of the current designing methods and tools, it is difficult to develop intelligent authoring systems that can guide users in order to produce more effective collaboration. One of the main difficulties with creating a more consistent (computer-understandable) approach to designing collaboration is the necessity of proposing better ways to formalize the group learning processes. In this paper, we present an innovative approach that uses ontologies and concepts from learning theories to create a framework that represents collaborative learning and its processes. Ontologies provide the necessary formalization to represent collaboration, while learning theories provide the concepts to justify and support the development of effective learning scenarios. Such an approach contributes to establish the foundations for the development of the next generation of intelligent authoring systems referred to as theory-aware systems. To verify the viability and usefulness of our proposed ontological framework in the context of systematic design, the development and use of an intelligent authoring tool for CSCL design is presented. This system is able to reason on ontologies to give suggestions that help users to create theory-compliant collaborative learning scenarios. We carried out several experiments with teachers in a geometry drawing course and the results indicate that the system helps teachers to create and interchange their scenarios more easily and facilitates the selection of important pedagogical strategies that influence positively the designing and effectiveness of group activities.     

多媒体结构的设计与选择

构造一个上下文敏感,具有可交互性的多媒体表示远比单纯构造视听信息或者单纯构造文本信息复杂得多.多媒体对象之间的交互需要有一个用来同步和异步交互的,包括立即响应的时空关系组织起来.根据构造环境的需要来考虑多媒体的结构构造.先通过介绍影响多媒体结构构造的7个要素来认识多媒体,然后在4种典型的构造模式中进行多媒体环境的选择.这4种构造模式分别是:结构化、时间关系、图关系、脚本形式.通过各种各样的观察和分析发现,结构化的多媒体构造为多媒体的表示提供了最为有效的表示形式.     

The perils of creating a class Web site: it was the best of times,it was the …

This article explains the visual and computing demands of Web-site authoring in a junior level, undergraduate honors course at a large public university. We argue that the students in this course—highly literate and skilled in the production of conventional printed academic writing—performed much like basic writers when challenged with acquiring a broad set of new visual and computer literacy skills. We argue for the value of the illustrated essay as a halfway point for connecting our expectations of Web site authoring to students’ previous experiences with the production of printed academic discourse.     

AI meets authoring: User models for untelligent multimedia

Authoring is a complex, knowledge-intensive activity which until recently has been performed exclusively by humans. New computer-based techniques have added horsepower rather than intelligence to traditional approaches, and have not addressed their principal limitations, chief of which is the inability to tailor presentations to individual users at run-time.We believe a model of the user is needed to support this kind of run-time determination of formand content. We describe our approach to the acquisition, representation and exploitation of user models: themost plausible user model is the result of an abductiverecognition process and it incorporates assumptions about the user which are then used to constrain thedesign by abduction of the best presentation. Both recognition and design processes are performed at run-time. We describe a prototypical implementation designed to demonstrate these ideas in the domain of video authoring.Our approach to authoring is intended to apply across multiple media; we have demonstrated these ideas with video because authoring in the video medium with traditional approaches inherits and exacerbates the problems from traditional media, and because the popularity of video as an authoring medium continues to grow.     

Creating a clickable TV program by sketching and tracking freeform triggers

Viewers watching Interactive TV can click on video objects on the screen, connecting them to an advertisement or more detailed content. But this requires an interactive authoring process to attach triggers to clickable objects, which is time-consuming because these objects can appear intermittently, move, and change shape. We facilitate authoring by combining a sketching interface with shot-based object tracking and trigger verification. Experiments involving professional video authors and non-specialist viewers suggest that this approach is an improvement on previous methods.     

Designing audio-enhanced paper photos for older adult emotional wellbeing in communication therapy

This article introduces audio-enhanced paper photos enabled by digital pen technology as an interaction paradigm for supporting and understanding emotional wellbeing in late adulthood, particularly in the context of communication therapy activities and related social interactions. We describe the development of a multimodal pen-based system that enables creation of audio-enhanced paper photos and the application of this technology to two domains: older adults with aphasia working to regain expressive and receptive language after a stroke, and older adults wanting to interact with a family member of advanced age with memory loss. Our pen-based authoring software enables caregivers, both therapists and family members, to create audio-enhanced paper photos to encourage meaningful and emotionally appropriate interaction with the older adults they support. We examine the ways in which emotional information is embedded in audio-enhanced photos and how this approach addresses various aspects of emotional wellbeing in late adulthood.     

Taking advantage of metadata semantics: the case of learning-object-based lesson graphs

Learning objects (LOs) are pieces of educational material characterized with a valuable amount of information about their content and usage. This additional information is defined as a set of metadata generally following the IEEE LOM specification. This specification also serves to characterize the relations existing between LOs. LOs whose relations are explicit are regarded as the nodes of a lesson graph. Link types and LO metadata constitute the lesson graph semantics. This article proposes to take advantage of lesson graph semantics using a context diffusion approach. It consists in diffusing the metadata-based processes along the edges of the lesson graph. This technique aims at coping with the metadata processing issues arising when some graph metadata are missing, incorrect, or incomplete. This article also presents a three-layer extensible framework for easing the use of context diffusion in a graph. As part of the framework, two original types of metadata processes are introduced. The first one takes advantage of the metadata attribute similarities between related LOs. The second one focuses on the lesson graph consistency. The framework and the application examples were implemented as an open-source Java library used in the lesson graph authoring tool LessonMapper2. During the lesson authoring process, we show that the framework can bring support not only for generating and validating metadata, but also for retrieving LOs.     

Interpreting Presuppositions Using Active Logic: From Contexts to Utterances

Presupposition is a pervasive feature of human language. It involves many interesting interactions between the utterances of a discourse and the context of the discourse. In this paper we focus on issues of logical form connected with the interaction of presupposition and discourse context, and illustrate our theory with some implementational work using the active logic framework. After reviewing some of the major issues in presupposition theory we turn to a largely successful unified approach of Heim. We show how the main principles of this theory can be implemented in active logic. But we also find two serious difficulties. These consist in (a) a straightforward counterexample and (b) a type of discourse that we call a garden‐path discourse. We maintain that both the counterexample and the garden‐path type of discourse can be handled by our active‐logic version of Heim's theory. This requires us to reformulate and extend Heim's theorey. Although this work is largely theoretical, both Heim's theory and ours have important things to say about the incremental processing of the utterances that make up discourse. And we present our theory as a specification of a processing device that takes logical form of a sentence along with current discourse context as input and delivers an updated discourse context as output. As an experiment, we have implemented portions of this device.     

A generic approach for developing process-level hydrologic modeling components

Component software architectures offer an alternative approach for building large, complex hydrologic modeling systems. In contrast to more traditional software paradigms (i.e. procedural or object-oriented approaches), using component-based approaches allows individuals to construct autonomous modeling units that can be linked together through shared boundary conditions during a simulation run. One of the challenges in component-based modeling is designing a simple yet robust means for authoring model components. We address this challenge by presenting an approach for efficiently creating standards-based, process-level hydrologic modeling components. Using this approach, a hydrologic process is implemented as a modeling component by (1) authoring a configuration file that defines the properties of the component and (2) creating a class with three methods that define the pre-run, runtime, and post-run behavior of the modeling component. We present the design and implementation of this approach, which we call the Simple Model Wrapper (SMW), and demonstrate how it can be applied to create an Open Modeling Interface (OpenMI)-compliant modeling component for a basic hydrologic process.     

Context‐Centric Speech‐Based Human–Computer Interaction

This paper describes research that addresses the problem of dialog management from a strong, context‐centric approach. We further present a quantitative method of measuring the importance of contextual cues when dealing with speech‐based human–computer interactions. It is generally accepted that using context in conjunction with a human input, such as spoken speech, enhances a machine's understanding of the user's intent as a means to pinpoint an adequate reaction. For this work, however, we present a context‐centric approach in which the use of context is the primary basis for understanding and not merely an auxiliary process. We employ an embodied conversation agent that facilitates the seamless engagement of a speech‐based information‐deployment entity by its human end user. This dialog manager emphasizes the use of context to drive its mixed‐initiative discourse model. A typical, modern automatic speech recognizer (ASR) was incorporated to handle the speech‐to‐text translations. As is the nature of these ASR systems, the recognition rate is consistently less than perfect, thus emphasizing the need for contextual assistance. The dialog system was encapsulated into a speech‐based embodied conversation agent platform for prototyping and testing purposes. Experiments were performed to evaluate the robustness of its performance, namely through measures of naturalness and usefulness, with respect to the emphasized use of context. The contribution of this work is to provide empirical evidence of the importance of conversational context in speech‐based human–computer interaction using a field‐tested context‐centric dialog manager.     

汉语显式篇章关系分析

篇章关系分为显式和隐式两种。显式关系的显著特征是篇章的基本单元之间存在显式连接词。针对汉语显式篇章关系,构建了包括汉语连接词识别和篇章关系分类的显式篇章关系分析平台。该文选取汉语宾州树库(Chinese Penn Treebank, CTB)中的500篇文本进行了汉语显式篇章关系标注;结合连接词的中心词,采用最大熵分类器构建了汉语连接词识别模块,其性能F₁值达到了66.79%;基于连接词及其词性等上下文特征,构建了篇章关系分类器,其在最顶层4大类语义关系上的分类性能的F₁值为91.92%。     

Employing personality-rich virtual persons—New tools required

Digital personalities are virtual characters that possess situation dependent, personality revealing behaviors. This paper introduces concepts, current and prospective usages of personality-rich virtual characters, and focus on authoring issues for artists that want to create digital portrays of digital persons. Different categories of digital personalities are introduced, in particular virtual actors for CG-movies are explained in more detail because of the importance of understanding the functioning of virtual actors—other types of virtual personalities will often be build upon the faculties of virtual actors. It is proposed that an essential feature of the prospective authoring process of digital personalities is the support of generalization. This would allow for a “concrete authoring”, that modifies and defines concrete cases. Thus, the author would be able to employ concrete cases as basis for generalizations. In this context, possible technologies that would support a concrete authoring process are presented, in particular Case-Based Reasoning.     

ZYX-a multimedia document model for reuse and adaptationof multimedia content

Advanced multimedia applications require adequate support for the modeling of multimedia content by multimedia document models. More and more this support calls for not only the adequate modeling of the temporal and spatial course of a multimedia presentation and its interactions, but also for the partial reuse of multimedia documents and adaptation to a given user context. However, our thorough investigation of existing standards for multimedia document models such as HTML, MHEG, SMIL, and HyTime leads to us the conclusion that these standard models do not provide sufficient modeling support for reuse and adaptation. Therefore, we propose a new approach for the modeling of adaptable and reusable multimedia content, the Z_YX model. The model offers primitives that provide-beyond the more or less common primitives for temporal, spatial, and interaction modeling-a variform support for reuse of structure and layout of document fragments and for the adaptation of the content and its presentation to the user context. We present the model in detail and illustrate the application and effectiveness of these concepts by samples taken from our Cardio-OP application in the domain of cardiac surgery. With the Z_YX model, we developed a comprehensive means for advanced multimedia content creation: support for template-driven authoring of multimedia content and support for flexible, dynamic composition of multimedia documents customized to the user's local context and needs. The approach significantly impacts and supports the authoring process in terms of methodology and economic aspects     

Overcoming the pitfalls of ontology authoring: Strategies and implications for tool design

The process of authoring ontologies appears to be fragmented across several tools and workarounds, and there exists no well accepted framework for common authoring tasks such as exploring ontologies, comparing versions, debugging, and testing. This lack of an adequate and seamless tool chain potentially hinders the broad uptake of ontologies, especially OWL, as a knowledge representation formalism. We start to address this situation by presenting insights from an interview-based study with 15 ontology experts. We uncover the tensions that may emerge between ontology authors including antagonistic ontology building styles (definition-driven vs. manually crafted hierarchies). We identify the problems reported by the ontology authors and the strategies they employ to solve them. These data are mapped to a set of key design recommendations, which should inform and guide future efforts for improving ontology authoring tool support, thus opening up ontology authoring to a new generation of users. We discuss future research avenues in light of these results.     

A new kernel-based approach for linear system identification

This paper describes a new kernel-based approach for linear system identification of stable systems. We model the impulse response as the realization of a Gaussian process whose statistics, differently from previously adopted priors, include information not only on smoothness but also on BIBO-stability. The associated autocovariance defines what we call a stable spline kernel. The corresponding minimum variance estimate belongs to a reproducing kernel Hilbert space which is spectrally characterized. Compared to parametric identification techniques, the impulse response of the system is searched for within an infinite-dimensional space, dense in the space of continuous functions. Overparametrization is avoided by tuning few hyperparameters via marginal likelihood maximization. The proposed approach may prove particularly useful in the context of robust identification in order to obtain reduced order models by exploiting a two-step procedure that projects the nonparametric estimate onto the space of nominal models. The continuous-time derivation immediately extends to the discrete-time case. On several continuous- and discrete-time benchmarks taken from the literature the proposed approach compares very favorably with the existing parametric and nonparametric techniques.     

COM组件技术在多媒体软件开发中的应用

提出了一种采用COM组件技术和著作系统相结合的方式开发高质量多媒体课件的方法，在著作系统支持的开放体系结构的基础上，新的基于COM组件技术的功能可以被加入到多媒体课件中，并举例说明，利用COM组件技术和基于MOA（Macromedia Open Architecture)的Xtras进行进程间通信，多媒体课件可以和其他应用程序进行交互。     

Deriving requirements from process models via the problem frames approach

Jackson's problem frames is an approach to describing a recurring software problem. It is presumed that some knowledge of the application domain and context has been gathered so that an appropriate problem frame can be determined. However, the identification of aspects of the problem, and its appropriate ‘framing’ is recognised as a difficult task. One way to describe a software problem context is through process modelling. Once contextual information has been elicited, and explicitly described, an understanding of what problems need to be solved should emerge. However, this use of process models to inform requirements is often rather ad hoc; the traceability from business process to software requirement is not always as straightforward as it ought to be. Hence, this paper proposes an approach for deriving and contextualising software requirements through use of the problem frames approach from business process models. We apply the approach on a live industrial e-business project in which we assess the relevance and usefulness of problem frames as a means of describing the requirements context. We found that the software problem did not always match easily with Jackson's five existing frames. Where no frame was identified, however, we found that Jackson's problem diagrams did couch the requirements in their right context, and thus application of the problem frames approach was useful. This implies a need for further work in adapting a problem frames approach to the context of e-business systems.     

The semantic pathfinder: using an authoring metaphor for generic multimedia indexing

This paper presents the semantic pathfinder architecture for generic indexing of multimedia archives. The semantic pathfinder extracts semantic concepts from video by exploring different paths through three consecutive analysis steps, which we derive from the observation that produced video is the result of an authoring-driven process. We exploit this authoring metaphor for machine-driven understanding. The pathfinder starts with the content analysis step. In this analysis step, we follow a data-driven approach of indexing semantics. The style analysis step is the second analysis step. Here, we tackle the indexing problem by viewing a video from the perspective of production. Finally, in the context analysis step, we view semantics in context. The virtue of the semantic pathfinder is its ability to learn the best path of analysis steps on a per-concept basis. To show the generality of this novel indexing approach, we develop detectors for a lexicon of 32 concepts and we evaluate the semantic pathfinder against the 2004 NIST TRECVID video retrieval benchmark, using a news archive of 64 hours. Top ranking performance in the semantic concept detection task indicates the merit of the semantic pathfinder for generic indexing of multimedia archives.