Communicating Mobile Processes

This paper presents a new model for mobile processes in occam-pi. A process, embedded anywhere in a dynamically evolving network, may suspend itself mid-execution, be safely disconnected from its local environment, moved (by communication along a channel), reconnected to a new environment and reactivated. Upon reactivation, the process resumes execution from the same state (i.e. data values and code positions) it held when it suspended. Its view of its environment is unchanged, since that is abstracted by its synchronisation (e.g. channels and barriers) interface and that remains constant. The environment behind that interface will (usually) be completely different. The mobile process itself may contain any number of levels of dynamic sub-network. This model is simpler and, in some ways, more powerful than our earlier proposal, which required a process to terminate before it could be moved. Its formal semantics and implementation, however, throw up extra challenges. We present details and performance of an initial implementation

Technology, Theology, Thinking, and the Church

From the midst of what sometimes seems a brave new world of communication—Web 2.0, blogs, mobile phone service from almost anywhere, video by mobile phone—we should not forget that the Church and humanity have lived through it all before. In fact, our communication revolution follows several others, dating back at least 3500 years, starting with the invention of writing, jumping to the mechanical writing of the printing press, to the electrical communication of the telegraph, and finally to our electronic world. At each stage, humans encoded communication in ever more complex symbolic and technical systems, which make communication more powerful but require more sophisticated interpretation. Both have an interesting and not always predictable impact on theology and Church life. The pattern of our communication and the larger communication world, of which it forms a part, create a communication environment for human living. Like any environment, one can study it, and people do, under the general title media ecology. What can we know about the communication environment? Several principles apply to its study. First, like all environments, its elements interact and affect each individual and process within it. Second, a change in one area will lead to changes in others—enhancing or diminishing them, for example. Third, people often take their environments for granted; not noticing them, they do not notice their influence. Media ecology attempts to call attention to the environment created by communication. To see how communication technology has influenced the Church, we can start with how the People of God have interacted and shared their faith. It shouldn’t surprise us to see changes in one area—communication technology—prompting changes in another—the articulation of faith; similarly, we should not find it surprising that other parts of the environment (including religious practices) trigger changes in communication. Addressing only writing, Walter Ong, S.J., memorably called attention to this pattern of interacting changes with a chapter heading, “writing restructures consciousness.” Here he traced thousands of years of the history of writing systems, using evidence from oral tales, proverbs, and epic poetry, and later novels and printed texts, to show how key elements of our thinking processes and self-consciousness changed once humans had mastered writing

Scholarly Publishers and Scholarly Publishing in an Electronic World

Argues that the present publishing model is not infinitely sustainable in the emerging electronic environment. Publishers are seen as protectionist and displaying the classic Luddite approach to fundamental revolutions by erecting barriers against innovators and are then a hindrance to scholarly communication. While there is little doubt that publishers can and do add value to the scholarly communication process, it may be that a quite different breed of publishers will emerge

Dynamics Governing Women's Decision on Reproductive Health Matters: Reflections from a Qualitative Study in Central India

One of the major challenges of Reproductive and Child Health Programme in India is addressing the barriers in communication and improve dialogue between diverse stakeholders, particularly women in the community. Through a qualitative study conducted in one of the rural districts of India, it was attempted to understand the factors affecting women's decision-making process. It is observed that most of the factors are affected by strong intrinsic environment and hence it becomes important for programme managers to understand the environment first in order to design an acceptable and effective communication strategy. In this study, knowledge, tradition, stigma and accessibility of services are identified as the key primary factors affecting decision making of women in the community, particularly on their health related issues. These in turn are governed by various supporting factors. Finally, it is observed that communication strategies can achieve their desired objective only when the local intrinsic environment is taken into cognisance

A particle system in interaction with a rapidly varying environment: Mean field limits and applications

We study an interacting particle system whose dynamics depends on an interacting random environment. As the number of particles grows large, the transition rate of the particles slows down (perhaps because they share a common resource of fixed capacity). The transition rate of a particle is determined by its state, by the empirical distribution of all the particles and by a rapidly varying environment. The transitions of the environment are determined by the empirical distribution of the particles. We prove the propagation of chaos on the path space of the particles and establish that the limiting trajectory of the empirical measure of the states of the particles satisfies a deterministic differential equation. This deterministic differential equation involves the time averages of the environment process. We apply our results to analyze the performance of communication networks where users access some resources using random distributed multi-access algorithms. For these networks, we show that the environment process corresponds to a process describing the number of clients in a certain loss network, which allows us provide simple and explicit expressions of the network performance.Comment: 31 pages, 2 figure

Evolution of plant reproduction: from fusion and dispersal to interaction and communication

Based on the existing data concerning the evolution of the sexual reproduction, it is argued that the processes of sex differentiation and interactions play a key role in evolution. From the beginning environment and organism are unified. In a changing dynamic environment life originates and the interaction between life and environment develops from simple to more complex organisms. Sexual reproduction is introduced after the origin of meiosis and is a key process in evolution. The asexual reproduction process prepares to dispersal. Sexual reproduction process adds the genome renewal and the gamete-gamete interaction. Reproduction and dispersal are connected and the process of reproduction has similarities between asexual and sexual reproduction. Unicellular algae develop the physiological and morphological sex differentiation. Sex differentiation is connected with the way of dispersal. The step to multicellular plants introduces cell isolation after meiosis and by the stay on the mother plant within a cell or organ, plant-cell apoplastic interaction originates and by prolonged stay the plant-plant interaction. This stay influences the type of dispersal. A life cycle with alternation of generations and two moments of dispersal permits plants to go on land. In ferns a shift in the moment of sex differentiation to meiospore happens and the stay of the macrospore leads to the seed plants. In water all types of sexual reproduction, interactions and the alternation of generations are prepared and these are used to conquest land. On land the biotic dispersal is realized. The phylogeny of sexual reproduction reveals that the sex differentiation and interaction are the main causes in the evolution of sexual reproduction. Sexual reproduction shows interactions during gamete fusion, between organism and environment and in multicellular plants between organisms. With respect to other types of interaction as in symbiosis or the nutrient chain, interaction is considered as an important action which is based on a persisting cooperation and points to a push during evolution. The push is expressed as communication: the driving force in the evolution. Based on the interactions between organisms and interactions between organisms and the dynamic environment, communication is considered as a driving force leading to the evolution as explained in the development of plant reproduction. Consequences for reproduction, its regulation and the process of evolution are discusse

Prototyping a process-centered environment

This paper describes an experimental system developed and used as a vehicle for prototyping the Arcadia-1 software development environment. Prototyping is viewed as a knowledge acquisition process and is used to reduce risks in software development by gaining rapid feedback about the suitability of a production system before the system is completed. Prototyping a software development environment is particularly important due to the lack of experience with them. There is an acute need to acquire knowledge about user interaction requirements for software environments. These needs are especially important for the Arcadia project, as it is one of the first attempts to construct a process-centered environment. Our prototyping effort addresses questions about effective interaction with a process-centered environment by simulating how Arcadia-1 would interact with users in a representative range of usage scenarios. We built a prototyping system, called PRODUCER, and used it to generate a variety of prototypes simulating user interactions with Arcadia-1 process programs.Experience with PRODUCER indicates that our approach is effective at risk reduction. The prototypes greatly improved communication with our customer. They confirmed some of our design decisions but also redirected our research efforts as a result of unexpected insight. We also found that prototyping usage scenarios provides conceptual guides and design information for process programmers. Most of the benefits of our prototyping effort derive from developing and interacting with usage scenarios, so our approach is generalizable to other prototyping systems. This paper reports on our prototyping approach and our experience in prototyping a process-centered environment

IREEL: remote experimentation with real protocols and applications over emulated network (extended version)

In the context of education, experimenting with networking protocols is a very important step in the learning process. These experiments are usually achieved using either simulation or real test bed. Progresses in high speed processing and networking enable the development of network emulators. These emulators use both real protocol implementations and network models that allow a controlled communication environment to be created

Engaging the Digitally Engaged Student: Comparing Technology-Mediated Communication Use and Effects on Student Learning

The role of communication technologies in the learning process is both a dynamic and complex issue. Yet, we know surprisingly little about how the use of specific communication technologies may influence classroom performance, key learning outcomes, and other measures of course satisfaction. The research reported here attempts to add to our knowledge about the role of communication in the technology enhanced classroom (TEC) education and in technology-enhanced online (TEO) education through a direct comparison of two courses. Our findings indicate additional support for “The No Significant Difference Phenomenon.” Furthermore, we found that prior experiences lead students to gravitate towards their preferred learning environments, and that basic website elements are required in any learning environment to enhance student outcomes. Finally, we found that when used appropriately, the benefits of communication technology use in education outweigh many of the drawbacks