Narrow Results

This paper discusses a supporting tool for developing software specifications in collaboration of a team — for cooperative specification processes. Typical cooperative specification processes consist of three phases — (1) making a working plan by a team in face-to-face session, (2) performing an assigned task, i.e. designing an assigned part by each member in distributed session, and (3) integrating the developed products in face-to-face session. In this paper, we focus on the support for the second phase, i.e. performing the distributed individual task that a team leader has assigned in the first phase. Our supporting tool consists of two parts; one is called method base, a kind of CASE tool for individual use, and the other is a structured E-mail system for communication use. Method base has various catalogued specification and design methods, so a worker can select a suitable method for his problem domain. He can be navigated through the CASE tool, e.g. the diagram editor, that supports the selected method. Method base has information about product structures and the relationships among the product structures of the different methods. Thus method base can integrate the products developed with the multiple methods by different workers into one. The tools for communications among other members are necessary, and especially a kind of structured E-mail system is very useful for the members to communicate with each other in the second phase. Our E-mail system supports (1) sending and receiving the products with messages or with comments by using hyper-link mechanism, (2) composing comprehensive messages easily by using templates, (3) storing messages in structured mail folders and retrieving them, and (4) automatically notifying the modification of products and the progress status of development activities to the workers.

Since it is necessary to realize virtual organizations in networks, to develop systems to be used for realizing various kinds of cooperation support among users is very important as a basis of virtual organizations. VIEW Media has been developed for such a purpose, utilizing CSCW (Computer Supported Cooperative Work) and database technologies. By introducing the concept of environment, VIEW Media supports flexible information sharing mechanisms. The major purpose of this paper is to show the advantages of the environment model for flexible sharing. Several well-known models are compared and then a representative model, the room model, is selected for comparison to develop the same application. Since the environment model is more general than the room model, we decided to develop "debate systems" which are rather complicated yet can be realized by both models. Debate systems can be regarded as generalization of conference systems and thus we believe the comparison is appropriate. By real usage of debate systems developed by VIEW Media (the environment model) and TeamWave (the room model), the environment model is shown to be suitable for such applications.

Locking is a commonly used mechanism in Computer Supported Cooperative Work (CSCW) for coordinating concurrent users and implementing various styles of information sharing. Part of a sharing style's definition is the granularity of shared objects. Since this varies among different applications, it is desirable to provide a range of different lock granules. In this paper, I first examine existing multiple granularity locking protocols and I evaluate their suitability for CSCW. My main contribution is the development of a new such protocol specifically for CSCW, which provides versionable object locking, guarantees conflict freedom, prevents update loss and ensures greater concurrency than other locking protocols. Its suitability for CSCW is justified by a comparative performance analysis.

Software development for computer-supported cooperative work (CSCW) is a notoriously difficult task, involving often concurrent processes which are bound up with rigid timing constraints. To cope effectively with this difficulty, we propose in this paper the use of abstract finite-state models. The utility of these models is illustrated by encoding a CSCW system that we have built into finite-state automata, specifying in them a number of desired properties with temporal logic, and verifying these properties with model checking. By incorporating timing constraints into this process, we also gain insight into the usability of our system in real cooperative scenarios.

Collaborative work is characterized by frequently changing situations and corresponding demands for tool support and interaction behavior provided by the collaboration environment. Current approaches to address these changing demands include manual tailoring by end-users and automatic adaptation of single user tools or for individual users. Few systems use context as a basis for adapting collaborative work environments, mostly focusing on document recommendation and awareness provision. In this paper, we present, firstly, a generic four layer framework for modeling and exploiting context. Secondly, a generic adaptation process translating user activity into state, deriving context for a given focus, and executing adaptation rules on this context. Thirdly, a collaboration domain model for describing collaboration environments and collaborative situations. Fourthly, examples of exploiting our approach to support context-based adaptation in four typical collaboration situations: co-location, co-access, co-recommendation, and co-dependency.

In this paper, we propose a software architecture based on Web services and Software agents for groupware tailorability. Through our literature study, we realize that the property of tailorability has a significant impact on designing collaborative applications. Although online applications in the recent years have been growing exponentially, online collaborative work between users is often supported by software applications that provide static basic functionalities, mostly centered on communication tools (text, audio and video). Hence, adding more sophisticated tools for enriching the collaborative experience, as for example, an integrated environment for task coordination and production, requires manually coding them into the application, which requires a significant effort in order to adapt the system to the real needs of users. In a collaborative context, the application designers are not able to predict all users' needs at design time. To remedy this problem, we propose a tailorable groupware architecture that enables the dynamic integration/composition of services into the collaborative application, gaining both in time and performance. Our work is based on the 3C functional model by Ellis that decomposes collaboration between users into communication, coordination and cooperation spaces. Through our research, we realized that Web services are powerful distributed components offering the desired tools to adapt a groupware to the real needs of users. In this paper, we propose a collaboration protocol based on Web services between machines over the network in order to exchange common services. Based on this protocol, we propose our groupware architecture, U3D, that introduces tailorability in collaboration applications.

Workflow management systems (WfMSs) also known as business process management systems (BPMSs) are increasingly popular in today’s large organizations. In spite of this popularity, many processes are still supported by ad hoc systems based, for example, on spreadsheets and homegrown databases. In particular, there is a lack of flexible process automation approaches that are able to bridge the gap between these ad hoc solutions and large-scale systems. This paper reports on a flexible WfMS and approach that blends formal and informal workflow modeling and execution, thus supporting different types of processes. We validate our work by discussing its design and implementation, and by analyzing its use in four different use cases within Siemens business units. We also discuss the role of action items as important flexibility mechanisms behind our model. Showing its ability to handle exceptions and ad hoc workflows.

This paper presents a distributed system for the cooperative design in a 3D virtual environment with full interactive 3D graphics functionality. The system includes a multi-site 3D cooperative editor, a database and a cooperative support platform. The users can design and modify a common 3D virtual world from remote sites simultaneously and cooperatively via long distance communication network. The design information can be stored into the design database and retrieved from it. The cooperative and communication support platform keeps the application away from the network process detail.

Real and virtual organizations are conducted by preferences, goals, and policies. Since virtual organizations have a two-level structure the preferences of these different levels are a source of conflicting interests. Also, management policies itself are subject to change, especially in a virtual setting. Therefore, agility has superior value, causing the need to develop business information and planning systems that may be adapted easily. Both mentioned aspects of business planning software, namely, ease adaptation on one side and the integration of individual preferences and goals on the other are treated in the paper. An architectural design is proposed that meets the needs of virtual organizations as far as any conflicts can be solved on an individual basis. This concept is further elaborated. Negotiating agents that obey the preferences of their principals are considered as a means to search for compromise solutions. An extensive example derived from hospital management illustrates the concept.

In distributed systems, traders mediate between clients and service providers. This paper introduces a trading model, which supports multiagent systems (MAS) and goes beyond simple trading in three ways: (a) Service composition — The trader composes complex services of the current service offers. During the composition, it checks the availability of the service offers. (b) Use of group agents — Group agents represent a group of agents with their individual policies and other context information. The trader can use the group agent's information for a pre-selection of service offers. (c) Adaptability — The trading model uses the notion of clients' trust into services and adapts to the clients' preferences and system policies. The trading model is used in a Computer-Supported Cooperative Work (CSCW) application, in which the trader finds adequate communication services for project teams with geographically distributed members.

Product development capability is more and more important for an enterprise in a knowledge-based economic era. In the philosophy of concurrent engineering, product development should be carried out in a concurrent way. Computer support is necessary for Concurrent Product Development (CPD). As an excellent tool to meet complex needs, CSCW has been used in CPD. But nearly all CSCW systems that have been developed so far concentrate on a more or less narrow sub-field of cooperative work. Thus, the need of integrated CSCW applications are apparent. The agent is a suitable programming paradigm that can be used to meet the complex needs. In this paper, a P-PROCE (Process, Product, Resource, Organization, Control & Evaluation) model is introduced for CPD firstly. By categorizing the agents of the multi-agent system (MAS) into different types of agent according to P-PROCE model and offering a structure of MAS, the CPD is mapped to MAS. The cooperation among agents is very important for MAS. In the paper, a two-layer cooperation structure of MAS is proposed. In the macro layer, agent based workflow control the CPD process and in the micro layer the entity agents interact with each other directly to fulfill the task. The key issues of these two cooperation layers are discussed in the paper. Component based structure of agent and an implemented case are also provided in the paper.

This paper introduces a novel sketch-based CSCW (Computer Supported Collaborative Works) system for UML design. Being different from traditional CSCW and CAD systems, our system uses free hand sketch as user interface, which will fully exploit the advantages of sketch — natural, convenient, and more capable of handling brainstorm. When using sketch as interface in CSCW systems, two problems have to be solved first: (1) how to store, edit and exchange sketch-based document consistently; (2) how to visualize sketch-based document. To solve the first problem, we propose a new document format SKETCH, which is able to represent sketches and related semantics. To solve the second problem, we propose an ontology-based conceptual model which is helpful of recognizing sketches and providing uniform visualization of sketches. To demonstrate our ideas, we have developed a prototype system that can support simple UML Class Diagram design in collaborative environment. It shows us good results, but still, more works are going to be done in the future.

Motivated by the need to support concurrent, collaborative access to shared documents, we have designed and validated an architecture that integrates existing and familiar systems for client editing software and document repositories. Through Web-services, we achieve an open system wherein numerous clients can use varied editing tools to fit their preferences and access documents distributed on a heterogeneous collection of document repository systems (configuration management systems, or CMS). Our simulation results on numerous client/server configurations validate our architecture and demonstrate an increase in concurrent access to shared documents; by adding a Lock Manager to the server, our system achieves a 67% reduction in check-out failures. Additionally, we present a novel algorithm that avoids operational transformation (OT) by utilizing a dynamic, hierarchical locking scheme that is transparent to the user. This algorithm maximizes concurrent access and enables edit caching to minimize communication costs.