In this paper, a novel technique is presented to solve tolerance design problems. To achieve the desired performance tolerance, the technique uses a subtle, but significant, change in the design: the addition of a tuning parameter in place of an increase in component precision. Statistical models are used to develop a framework for the tuning parameter design method. Also developed is a new, di...

We show how mutually utility independent hierarchies, which weigh the various costs of an experiment against benefits expressed through a mixed Bayes linear utility representing the potential gains in knowledge from the experiment, provide a flexible and intuitive methodology for experimental design which remains tractable even for complex multivariate problems. A key feature of the approach is...

ÐMessage-driven confidence-driven (MDCD) error containment and recovery, a low-cost approach to mitigating the effect of software design faults in distributed embedded systems, is developed for onboard guarded software upgrading for deep-space missions. In this paper, we first describe and verify the MDCD algorithms in which we introduce the notion of ªconfidence-drivenº to complement the ªcomm...

The proposed software technique is a very low cost and an effective solution towards designing Byzantine fault tolerant computing application systems that are not so safety critical. It does not rely on multiple versions of software running simultaneously on multiple machines. The proposed software approach is to mask various hardware random errors on adopting the so-called, ESVP (an enhanced s...

The interactive video (IV) market has been expected t o capture a significant share of the huge potential revenues t o be g business and residential markets. The level of revenues generated depends on the completion rate of calls the service provide support, no matter what the IV system or network condition. Thus, a cost-effective, scalable fault-tolerant IV system is needed t mize the video ca...

This paper describes a framework and algorithms for robust kinematic design of mechanical assemblies. The framework, developed over a period of ten years, is based on the configuration space method and supports automatic modeling, nominal and toleranced analysis, and part tolerance envelope computation of open and closed loop planar mechanisms with multiple, changing contacts. It also supports ...

This paper describes the design and realization of a transition from a microstrip line to a ridge gap waveguide operating between 95 and 115 GHz. The study includes simulations, measurements, and a Monte Carlo analysis of the assembly tolerances. The purpose of this tolerance study is to identify the most critical misalignments that affect the circuit performance, and to provide guidelines abou...

Many fault tolerance techniques that have been devised, applied and improved over the past three decades represent general solutions to recurring problems in the design of fault tolerant computer systems. This document presents some of the best known such techniques, formatted as patterns and organized by a classification scheme into a system of patterns for fault tolerance. This pattern system...

Recently we developed a new tolerance modeling scheme, semantic tolerance modeling, to enable interpretable and accurate tolerance analysis. In this paper, a new dimensioning and tolerancing practice, semantic tolerancing, is proposed with the theoretical support of semantic tolerance modeling. Based on the principles of interpretability, this tolerancing approach allows for better design inten...

The mission of UNU/IIST is to assist developing countries in the application and development of software technology. UNU/IIST contributes through its programmatic activities: 1. advanced development projects in which software techniques supported by tools are applied, 2. research projects in which new techniques for software development are investigated, 3. curriculum development projects in wh...