J. Arlin Cooper

Fuzzy-Algebra Uncertainty Analysis for Abnormal-Environment Safety Assessment

Many safety analyses depend on uncertain inputs and on mathematical models chosen from various alternatives, but give fixed results implying no uncertainty. Conventional uncertainty analyses help, but are also based on assumptions and models, the accuracy of which may be difficult to assure. Some of the models and assumptions that on cursory examination seem reasonable can be misleading. As a result, quantitative assessments, even those accompanied by uncertainty measures, can give unwarranted impressions of accuracy. Because analysis results can be a major contributor to a safety-measure decision process, risk management depends on relating uncertainty to only the information available. The uncertainties due to abnormal environments are even more challenging than those in normal-environment safety assessments, and therefore require an even more cautious approach. A fuzzy-algebra analysis is proposed in this article that has the potential to appropriately reflect the information available and portray uncertainties well, especially for abnormal environments.

The Lightning Arrestor-Connector Concept: Description and Data

Experimental and theoretical data show that a new compact lightning arrestor can be incorporated into a multipin connector housing to protect components in missile, aircraft, and ground systems from lightning energy. This energy is sometimes transmitted into component compartments causing component burnout, ignition of explosives, and circuit malfunctions. By properly incorporating the lightning arrestor-connector, these effects can be minimized or eliminated. The lightning arrestor-connector concept has been analyzed, and prototype devices have been tested extensively at Sandia Laboratories. Production for use in several missile systems has begun. The design and initial development of the device is described along with data demonstrating the device behavior under simulated lightning tests.

Decision analysis for transportation risk management

Modern transport systems are complex, therefore requiring highly effective management decision tools. These tools would aid in ranking alternatives, allocating resources, and certifying critical transportation operations. Existing methods may not accommodate the dynamics of changing environments and personnel threats. They also may not handle hard-to-quantify, disparate data, and may be unable to realistically estimate uncertainty. In this paper, the authors discuss a coordinated set of ongoing model development efforts to overcome such difficulties.

MEMS safety switch for controlling critical software operations

This work is intended to help improve the safety of software-controlled safety-critical systems, while also helping to improve the mathematical characterization of such systems. Software processing is an essential part of many safety-critical operations. However, safety and reliability vulnerabilities are inherent in typical software logic and in hardware implementations representing the software logic, because it is impossible to assure perfect software, and it is difficult to make microelectronics invulnerable to many environments. Also, the safety of systems depending on software control is very difficult to assure probabilistically.

Integrating Monitoring and Decision Modeling within a Cooperative Framework: Promoting Transboundary Water Management and Avoiding Regional Conflict

Surface and groundwater resources do not recognize political boundaries. Where nature and boundary cross, tension over shared water resources can erupt. Such tension is exacerbated in regions where demand approaches or exceeds sustainable supplies of water. Establishing equitable management strategies can help prevent and resolve conflict over shared water resources. This paper describes a methodology for addressing transboundary water issues predicated on the integration of monitoring and modeling within a framework of cooperation. Cooperative monitoring begins with agreement by international scientists and/or policy makers on transboundary monitoring goals and strategies; it leads to the process of obtaining and sharing agreed-upon information among parties with the purpose of providing verifiable and secure data. Cooperative modeling is the process by which the parties jointly interpret the data, forecast future events and trends, and quantify cause and effect relationships. Together, cooperative monitoring and modeling allow for the development and assessment of alternative management and remediation strategies that could form the basis of regional watershed agreements or treaties. An example of how this multifaceted approach might be used to manage a shared water resource is presented for the Kura River basin in the Caucasus.

The Lightning Arrestor-Connector - A New Concept in System Electrical Protection

A new compact lightning arrestor can be incorporated into a connector housing to protect missile, aircraft and ground systems from lightning energy that can sometimes be transmitted to sensitive components on wires that pass into component compartments. This energy can cause component burnout, ignition of explosives, and circuit malfunctions. By properly incorporating the lightning arrestor-connector, these effects can be minimized or eliminated. The lightning arrestor-connector concept has been theoretically studied and prototype devices have been tested extensively at Sandia Laboratories. The design and development of the device is described along with data demonstrating the device behavior under simulated lightning tests.