Theory and design of reliable spacecraft data systems Quarterly progress report, 10 Aug. - 9 Nov. 1969

Design analysis and fault diagnosis for spacecraft data system

A survey of an introduction to fault diagnosis algorithms

This report surveys the field of diagnosis and introduces some of the key algorithms and heuristics currently in use. Fault diagnosis is an important and a rapidly growing discipline. This is important in the design of self-repairable computers because the present diagnosis resolution of its fault-tolerant computer is limited to a functional unit or processor. Better resolution is necessary before failed units can become partially reuseable. The approach that holds the greatest promise is that of resident microdiagnostics; however, that presupposes a microprogrammable architecture for the computer being self-diagnosed. The presentation is tutorial and contains examples. An extensive bibliography of some 220 entries is included

Theory and design of reliable spacecraft data systems

Theory and techniques applicable to design, analysis, and fault diagnosis of reliable spacecraft data system

An efficient logic fault diagnosis framework based on effect-cause approach

Fault diagnosis plays an important role in improving the circuit design process and the manufacturing yield. With the increasing number of gates in modern circuits, determining the source of failure in a defective circuit is becoming more and more challenging. In this research, we present an efficient effect-cause diagnosis framework for combinational VLSI circuits. The framework consists of three stages to obtain an accurate and reasonably precise diagnosis. First, an improved critical path tracing algorithm is proposed to identify an initial suspect list by backtracing from faulty primary outputs toward primary inputs. Compared to the traditional critical path tracing approach, our algorithm is faster and exact. Second, a novel probabilistic ranking model is applied to rank the suspects so that the most suspicious one will be ranked at or near the top. Several fast filtering methods are used to prune unrelated suspects. Finally, to refine the diagnosis, fault simulation is performed on the top suspect nets using several common fault models. The difference between the observed faulty behavior and the simulated behavior is used to rank each suspect. Experimental results on ISCAS85 benchmark circuits show that this diagnosis approach is efficient both in terms of memory space and CPU time and the diagnosis results are accurate and reasonably precise

Respect & Recognition: What’s the Story?

How do adults experience disrespect and respect in education? How do these experiences affect their identities, relationships and life choices? Has this return to learning had an impact on confidence, self-esteem or personal worth? What does education mean to the learner? In an attempt to answer these questions this research study explores the experience of respect in the lives of 8 students on a pre-access course in inner-city Dublin. My intention is to understand how the experience of respect or indeed the lack of respect affected their learning journeys and their life choices. The work of the American sociologist, Richard Sennett, informed my reading of respect and its impact on the individual in the new capitalism. This thesis introduces Sennett’s work as offering a wealth of observations and concepts important to adult educators struggling to navigate the fragmented and shifting waterways of neo liberal, instrumental education. This study is embedded in the recognition theory of Axel Honneth and Sennett’s research concerning respect over the past four decades. The methodology is grounded in social constructionism and the theory contributing is from the Frankfurt School of Critical Theory. The experiences of the research participants were accessed using narrative enquiry in one to one interviews. The research produced is qualitative and gleaned from the stories these individuals shared concerning their learning journeys, both in childhood and as adults. The primary sensitizing concept used in this research is respect. As such, learners’ life histories will be interpreted as containing moments of respect and disrespect and the consequences investigated. The research participants were positive in their views and experiences of returning to education. Each participant affirmed that education had increased her self-esteem and instilled in her the confidence to continue to engage and pursue further study at third level. The research clearly shows how little monetary reward is considered in the return to education. The primary aim of the participants is a general one of self improvement and development. As early school leavers the individuals in this research considered the path to third level a magical one that only the learned few could attain. The re engagement with education demystified this outlook and demonstrated how much could be achieved with the crucial ingredient of support. The findings of this research attest to the central role of respect both in the learning process and in the development of the individual. Relationships are at the centre of these learners’ stories; relationships that are interpreted as either respectful or disrespectful. These relationships are filled with incidents that are intensely personal and impact on how the individual perceives herself, forms relationships and makes life choices. The increase in confidence and self-esteem of the participants in this research has two aspects that inter relate; this is the connection between relationships and successful learning. The experience of respect is telling someone that they can achieve, that they are intelligent, they have value. In these interviews this happens in the classroom and replicates moments these research participants did not experience as children or young adults. Recommendations include raising awareness of the dynamics of intersubjective recognition for positive learning and self-esteem and the central role of respect for an adult education that seeks to promote citizenship and democratic participation. As such, the interpersonal space must now replace student centred learning as education is recognised as a mutual act that takes place together; it is not an individual process. And finally, educational relationships that are grounded in respect increase the self esteem of the learner and allow for the growth of confidence and personal worth so essential for the well-being of the individual and of society. This thesis is part of a re-defining of the concept of curriculum; lifelong learning is not a servant to the economy but is an essential element of being well and well being

Advanced data management system analysis techniques study

The state of the art of system analysis is reviewed, emphasizing data management. Analytic, hardware, and software techniques are described

Autonomous Recovery Of Reconfigurable Logic Devices Using Priority Escalation Of Slack

Field Programmable Gate Array (FPGA) devices offer a suitable platform for survivable hardware architectures in mission-critical systems. In this dissertation, active dynamic redundancy-based fault-handling techniques are proposed which exploit the dynamic partial reconfiguration capability of SRAM-based FPGAs. Self-adaptation is realized by employing reconfiguration in detection, diagnosis, and recovery phases. To extend these concepts to semiconductor aging and process variation in the deep submicron era, resilient adaptable processing systems are sought to maintain quality and throughput requirements despite the vulnerabilities of the underlying computational devices. A new approach to autonomous fault-handling which addresses these goals is developed using only a uniplex hardware arrangement. It operates by observing a health metric to achieve Fault Demotion using Recon- figurable Slack (FaDReS). Here an autonomous fault isolation scheme is employed which neither requires test vectors nor suspends the computational throughput, but instead observes the value of a health metric based on runtime input. The deterministic flow of the fault isolation scheme guarantees success in a bounded number of reconfigurations of the FPGA fabric. FaDReS is then extended to the Priority Using Resource Escalation (PURE) online redundancy scheme which considers fault-isolation latency and throughput trade-offs under a dynamic spare arrangement. While deep-submicron designs introduce new challenges, use of adaptive techniques are seen to provide several promising avenues for improving resilience. The scheme developed is demonstrated by hardware design of various signal processing circuits and their implementation on a Xilinx Virtex-4 FPGA device. These include a Discrete Cosine Transform (DCT) core, Motion Estimation (ME) engine, Finite Impulse Response (FIR) Filter, Support Vector Machine (SVM), and Advanced Encryption Standard (AES) blocks in addition to MCNC benchmark circuits. A iii significant reduction in power consumption is achieved ranging from 83% for low motion-activity scenes to 12.5% for high motion activity video scenes in a novel ME engine configuration. For a typical benchmark video sequence, PURE is shown to maintain a PSNR baseline near 32dB. The diagnosability, reconfiguration latency, and resource overhead of each approach is analyzed. Compared to previous alternatives, PURE maintains a PSNR within a difference of 4.02dB to 6.67dB from the fault-free baseline by escalating healthy resources to higher-priority signal processing functions. The results indicate the benefits of priority-aware resiliency over conventional redundancy approaches in terms of fault-recovery, power consumption, and resource-area requirements. Together, these provide a broad range of strategies to achieve autonomous recovery of reconfigurable logic devices under a variety of constraints, operating conditions, and optimization criteria

A Study of Technology Innovations and Applications in Transforming Safety and Security in Healthcare Facility Management

The increasing complexity of construction projects has transformed the Architecture, Engineering, and Construction (AEC) industry through technology adoption over the last decade. But, Facility Management (FM) as an industry has been slow in technology adoption. Growing market competition, corporate demands and new ways of attracting clients for owners are compelling FM professionals to be more efficient. This requirement is driving technology adoption by FM professionals. This study identifies technologies adopted by Healthcare Facility Management (HFM) professionals for improving safety and security of users that have capabilities and conceived and/or developed applications that can or in some cases are at present used in HFM. Simultaneously, it also looks into potentials and capabilities of a handful of other technologies in further improving safety and security. Using Literature-Based Discovery (LBD), the technology applications and innovations aimed towards safety and security are discovered from the literature that falls within the purview of HFM to form a picture of how these technologies enhance the practice of FM. The study aims at detecting how technologies have contributed towards transforming user experience. Also, this study identifies existing technologies and innovation demands (knowledge and gaps in knowledge), a general understanding of technology, its use and capabilities, and its recognition by users and industry professionals (adoption/rejection). They serve to illustrate how and to what degree the technologies will come to be used in facility management. Technologies, as they mature, will come to be used by facility managers in similar functions and hypothetically, entirely new ones. One should create a better user experience tailored to the functionality demanded. It is important for facility managers to partner with technology companies presenting innovative solutions to create a platform that is tailored to user-specific needs. Acceptance of a unified process, together with input from users, facility managers, and an assessment of current technologies and new advances in practice are productive ways to develop technologies that drive user satisfaction. This paper works to illustrate a future vision of HFM based on these technologies. Healthcare facility managers will have a reference that assembles multiple technological proficiencies that can function in their practice going forward

Techniques for the realization of ultra- reliable spaceborne computer Final report

Bibliography and new techniques for use of error correction and redundancy to improve reliability of spaceborne computer