Foundations of distributed interaction systems

There are numerous applications where a variety of human and software participants interactively pursue a given task (play a game, engage in a simulation, etc.). In this paper, we define a basic architecture for a distributed, interactive system (DIS for short). We then formally define a mathematical construct called a DIS abstraction that provides a theoretical basis for a software platform for building distributed interactive systems. Our framework provides a language for building multiagent applications where each agent has its own behaviors and where the behavior of the multiagent application as a whole is governed by one or more “master” agents. Agents in such a multiagent application may compete for resources, may attempt to take actions based on incorrect beliefs, may attempt to take actions that conflict with actions being concurrently attempted by other agents, and so on. Master agents mediate such conflicts. Our language for building agents (ordinary and master) depends critically on a notion called a “generalized constraint” that we define. All agents attempt to optimize an objective function while satisfying such generalized constraints that the agent is bound to preserve. We develop several algorithms to determine how an agent satisfies its generalized constraints in response to events in the multiagent application. We experimentally evaluate these algorithms in an attempt to understand their advantages and disadvantages. This revised version was published online in June 2006 with corrections to the Cover Date.     

Introduction

Multimedia Tools and Applications -     

Mining Online Opinions

Emerging opinion-mining technology makes it possible to aggregate and financially leverage the opinions of vast numbers of people.     

CARA: A Cultural-Reasoning Architecture

There's a constant need to reason about diverse cultures all over the world. Past cultural-reasoning research has focused primarily on techniques to organize, catalog, and reason about cultural and historical artifacts of the kind typically stored in a museum. This is extremely valuable. However, the term "cultural reasoning" as we use it in the previous examples (and in this article) focuses on understanding how different cultural groups today make decisions and what factors those decisions are based on. An architecture that supports cultural reasoning should, for example, be able to pinpoint characteristics that differentiate organizations engaging political action within legitimate frameworks from those engaging in violence and terror. Key in all this is that cultural reasoning must go hand in hand with environmental reasoning. We believe that any architecture to support cultural reasoning about a given group, political entity, business, or religious organization should contain these components: 1) a semantic Web extraction engine to elicit data about the organization, 2) an opinion-mining engine that captures the organization's opinions, 3) an algorithm to correlate environmental variables with actions that the organization takes, and 4) a simulation or game environment within which analysts and users can see what the organization has done and what it might do in hypothetical situations     

Design theory: a foundation of a new paradigm for design science and engineering

In recent years, the works on design theory (and particularly the works of the design theory SIG of the design society) have contributed to reconstruct the science of design, comparable in its structure, foundations and impact to decision theory, optimization or game theory in their time. These works have reconstructed historical roots and the evolution of design theory, conceptualized the field at a high level of generality and uncovered theoretical foundations, in particular the logic of generativity, the “design-oriented” structures of knowledge, and the logic of design spaces. These results give the academic field of engineering design an ecology of scientific objects and models, which allows for expanding the scope of engineering education and design courses. They have contributed to a paradigm shift in the organization of R&D departments, supporting the development of new methods and processes in innovation departments, and to establishing new models for development projects. Emerging from the field of engineering design, design theory development has now a growing impact in many disciplines and academic communities. The research community may play a significant role in addressing contemporary challenges if it brings the insights and applicability of design theory to open new ways of thinking in the developing and developed world.     

Shared memory in design: A unifying theme for research and practice

This paper presents a new unifying theme for design theory by emphasizing the importance of context. We arrive at our conclusions by examining and then criticizing the legitimacy of universal methods in design upon which the critical importance of context emerges. The collaborative aspects of design focuses attention on the conception of shared meaning. We introduce and elaborate the concept of shared memory as the embodiment both of context and of shared meaning. Using the concept of shared memory in vertical and horizontal forms, within and between disciplines, respectively, we both account for past observations of design in practice and recommend actions to improve design in the future. We examine several practical implications of the growing importance of shared memory in industrial firms and for design teams. We then consider and recommend specific research programs which will help designers capture and make better use of this critical resource.     

View management in multimedia databases

Abstract. Though there has been extensive work on multimedia databases in the last few years, there is no prevailing notion of a multimedia view, nor there are techniques to create, manage, and maintain such views. Visualizing the results of a dynamic multimedia query or materializing a dynamic multimedia view corresponds to assembling and delivering an interactive multimedia presentation in accordance with the visualization specifications. In this paper, we suggest that a non-interactive multimedia presentation is a set of virtual objects with associated spatial and temporal presentation constraints. A virtual object is either an object, or the result of a query. As queries may have different answers at different points in time, scheduling the presentation of such objects is nontrivial. We then develop a probabilistic model of interactive multimedia presentations, extending the non-interactive model described earlier. We also develop a probabilistic model of interactive visualization where the probabilities reflect the user profiles, or the likelihood of certain user interactions. Based on this probabilistic model, we develop three utility-theoretic based types of prefetching algorithms that anticipate how users will interact with the presentation. These prefetching algorithms allow efficient visualization of the query results in accordance with the underlying specification. We have built a prototype system that incorporates these algorithms. We report on the results of experiments conducted on top of this implementation. Received June 10, 1998 / Accepted November 10, 1999     

Computing most probable worlds of action probabilistic logic programs: scalable estimation for 1030,000 worlds

The semantics of probabilistic logic programs (PLPs) is usually given through a possible worlds semantics. We propose a variant of PLPs called action probabilistic logic programs or -programs that use a two-sorted alphabet to describe the conditions under which certain real-world entities take certain actions. In such applications, worlds correspond to sets of actions these entities might take. Thus, there is a need to find the most probable world (MPW) for -programs. In contrast, past work on PLPs has primarily focused on the problem of entailment. This paper quickly presents the syntax and semantics of -programs and then shows a naive algorithm to solve the MPW problem using the linear program formulation commonly used for PLPs. As such linear programs have an exponential number of variables, we present two important new algorithms, called and to solve the MPW problem exactly. Both these algorithms can significantly reduce the number of variables in the linear programs. Subsequently, we present a “binary” algorithm that applies a binary search style heuristic in conjunction with the Naive, and algorithms to quickly find worlds that may not be “most probable.” We experimentally evaluate these algorithms both for accuracy (how much worse is the solution found by these heuristics in comparison to the exact solution) and for scalability (how long does it take to compute). We show that the results of are very accurate and also very fast: more than 10^30,000 worlds can be handled in a few minutes. Subsequently, we develop parallel versions of these algorithms and show that they provide further speedups.      

Restless leg syndrome presenting as chronic severe limb pain in a dialysis patient

“Chronic pain” is a commonly reported symptom among hemodialysis patients. Despite its high prevalence and the poor health-related quality of life associated with it, chronic pain remains an ineffectively assessed and managed entity in dialysis patients. We report a case of a 55-year-old gentleman on maintenance hemodialysis who presented with 3 months history of “excruciating flitting and fleeting type” of pain largely involving both lower limbs and occasionally neck, shoulder, chest, and upper limbs. The pain was so intolerable that it even triggered suicidal intentions in the patient. Common causes of chronic pain in dialysis patients were considered, but the initial history and clinical examination remained elusive. The patient was empirically started on oral analgesics, benzodiazepines, calcitriol, and levocarnitine supplementation but had no significant effect on his symptoms. A comprehensive repeat clinical history revealed the nocturnal periodicity of symptoms, specific aggravation of pain with inactivity, and its temporary relief with movement. This helped us narrow down the diagnosis to restless leg syndrome (RLS) amidst the myriad causes of chronic pain in dialysis patients. The “constant urge to move the legs” which is the defining characteristic of RLS was inconspicuous in our patient and excruciating pain was the predominant manifestation. This atypical presentation of RLS with agonizing pain involving multiple sites of the body led to a delay in the diagnosis and initiation of appropriate therapeutic measures. The patient had a dramatic response to therapy with dopamine agonists and withdrawal of the drug led to reappearance of his symptoms which further confirmed the diagnosis of RLS. RLS should be considered in the evaluation of chronic pain in dialysis patients and renal health care providers should familiarize themselves with the varied atypical, forme fruste manifestations of RLS to avoid diagnostic delay of this disabling but treatable condition.