Jose J. Gonzalez

Cooperative effects in random sequential polymer reactions

Abstract We consider the kinetics of a reaction in a polymer system where each reacted unit protects its (r—1)-nearest neighbours completely against reaction and modifies the reactivity of the r-nearest neighbours. The number of sequences containing a specified numberof unreacted units, together with the over-all extent of reaction, is determined as function of time. In a continuum limit the model also describes the time evolution of a sequential filling of hard rods on a line

Maintaining Security and Safety in High-Threat E-Operations Transitions

Migrating to new modes of operation are perilous times for most organizations. For firms that routinely work in high-threat, high-reward situations, the risks of innovation are particularly challenging. This paper develops a systems-based approach to understanding these risks. We draw examples from one firm migrating to e-operations for offshore oil platforms to increase profitability. The firm recently participated in a facilitated group model building exercise to examine the effects of the migration on the organization, and found several interesting and unanticipated barriers and hazards to the transition. The results of the workshop demonstrate the use of qualitative modeling approaches to complex problems, as well as a method to reduce concern about data confidentiality in security-conscious environments.¹

Applying system dynamics to courseware development

The general purpose of the work reported here is to extend and validate system dynamics technologies for their use in managing the complexities and risks of large scale, courseware development projects. Courseware refers to a variety of computer-based instructional materials used for the purpose of creating effective learning environments. While the costs for computer hardware are generally declining, new hardware and software technologies are appearing with a frequency that makes it a serious challenge to hire and train designers, developers and project managers and to plan and produce computer-based instructional materials that are both effective (in terms of learning) and efficient (in terms of costs and technology utilization).

Integrating Systems Thinking and Instructional Science

This chapter presents the young discipline of systems thinking, that is, study of structure, behavior and management of complex systems. We approach systems thinking from two different, though supplementary angles: modeling and simulation (system dynamics), and cognitive psychology of decision making in complex systems. We argue that progress in management of systems requires that system dynamics, cognitive psychology, learning theory and simulation-based instructional design be combined through a framework for automation of instructional system development. We expect this approach to produce insights of general validity to the field of ISD at large.

Improving tools to create learning laboratories for complex problem solving

The experimental results for problem-solving behavior in complex, dynamic systems, though extremely rich and varied, give some clear indications as to how learning laboratories should be devised. However, the best learning laboratories tend to be very resourceful and costly. This paper describes an evolving approach for the design of effective learning laboratories at lower cost by using new tools and combining existing tools in innovative ways.

Introduction to the communication and information systems technology for emergency management minitrack

Communication and Information System Technology is profoundly changing the management of disasters and emergencies. Mobile devices and social media are being used by citizens in innovative ways to help them manage the consequences of disasters for themselves, families, and communities. The trend of increasing traffic flow originating from affected citizens poses many research challenges.

Employment of System Dynamics in Modeling of Instructional Design (ISD4)

In June of 1994, the authors of this chapter met in Grimstad to develop a research agenda to apply system dynamics to instructional design. The purpose of the research and development project is to extend and validate system dynamics technologies for their use in managing the complexities and risks of large-scale, courseware design projects. Courseware consists of a variety of computer-based instructional materials used for the purpose of creating effective learning environments. While computer costs are dropping, new interactive technologies are appearing with a frequency that makes it quite difficult to plan and produce optimally effective (in terms of learning) and efficient (in terms of costs) computer-based instructional materials.

Mass dependence on the quantized fields in quantum electrodynamics

Abstract In this paper it is shown that the mass dependence on quantized fields has always been overlooked when variational principles have been applied. Since the field dependence of the mass was the crucial observation leading to Kramers renormalization principle one expects this inconsistency to be related to the well-known convergence difficulties. We discuss the implications of the field dependence of the mass in quantum electrodynamics, provided that the Hamiltonian formalism is applicable. It is shown that new terms describing weak and strong interactions appear in the field equations. These new terms describe a virtual “structure” of the particles. This virtual structure is neither in contradiction with experimental facts nor does it violate secured theoretical results. Its relation with form factors is discussed.