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For five decades, the semiconductor industry has distinguished itself by the rapid pace of improvement in miniaturization of electronics products-Moore's Law. Now, scaling hits a brick wall, a paradigm shift. The industry roadmaps recognized the scaling limitation and project that packaging technologies will meet further miniaturization needs or ak.a "More than Moore". This paper presents packaging technology trends and accelerated reliability testing methods currently being practiced. Then, it presents industry status on key advanced electronic packages, factors affecting accelerated solder joint reliability of area array packages, and IPC/JEDEC/Mil specifications for characterizations of assemblies under accelerated thermal and mechanical loading. Finally, it presents an examples demonstrating how Accelerated Testing and Analysis have been effectively employed in the development of complex spacecraft thereby reducing risk. Quantitative assessments necessarily involve the mathematics of probability and statistics. In addition, accelerated tests need to be designed which consider the desired risk posture and schedule for particular project. Such assessments relieve risks without imposing additional costs. and constraints that are not value added for a particular mission. Furthermore, in the course of development of complex systems, variances and defects will inevitably present themselves and require a decision concerning their disposition, necessitating quantitative assessments. In summary, this paper presents a comprehensive view point, from technology to systems, including the benefits and impact of accelerated testing in offsetting risk.

This report presents the results of a preliminary investigation of the feasibility of incorporating structural degradation into time-dependent reliability analysis of navigation infrastructure on inland and coastal waterways. An appraisal is presented of methodologies for engineering decision that might enable the owner/operator of a navigation facility to perform condition assessments, determine its economical remaining service life, and schedule routine maintenance and repair so as to minimize total operating costs without endangering public safety. The report is developed around the following specific research objectives: (1) Identify mathematical models to evaluate degradation in strength of navigation structures over time in terms of initial construction conditions, servicc load history, and aggressive environmental factors. (2) Develop a methodology to assess the probability that structural capacity has degraded below a specified level, taking into account initial conditions of the structure, service load history and structural aging, and deterioration. (3) Examine the role played by peridic inspection, nondestructive evaluation and maintenance in maintaining reliability and minimizing overall costs during a projected service period. This feasibility study is based on a review, synthesis and interpretation of existing procedures and data in the structural engineering, material science, and structural reliability literature. It provides a prospectus for subsequent research on reliabiity-based evaluation of navigation structures, some of which is initiating. (MM)

This report presents the results of a preliminary investigation of the feasibility of incorporating structural degradation into time-dependent reliability analysis of navigation infrastructure on inland and coastal waterways. An appraisal is presented of methodologies for engineering decision that might enable the owner/operator of a navigation facility to perform condition assessments, determine its economical remaining service life, and schedule routine maintenance and repair so as to minimize total operating costs without endangering public safety. The report is developed around the following specific research objectives: (1) Identify mathematical models to evaluate degradation in strength of navigation structures over time in terms of initial construction conditions, servicc load history, and aggressive environmental factors. (2) Develop a methodology to assess the probability that structural capacity has degraded below a specified level, taking into account initial conditions of the structure, service load history and structural aging, and deterioration. (3) Examine the role played by peridic inspection, nondestructive evaluation and maintenance in maintaining reliability and minimizing overall costs during a projected service period. This feasibility study is based on a review, synthesis and interpretation of existing procedures and data in the structural engineering, material science, and structural reliability literature. It provides a prospectus for subsequent research on reliabiity-based evaluation of navigation structures, some of which is initiating. (MM)

This report presents the results of a preliminary investigation of the feasibility of incorporating structural degradation into time-dependent reliability analysis of navigation infrastructure on inland and coastal waterways. An appraisal is presented of methodologies for engineering decision that might enable the owner/operator of a navigation facility to perform condition assessments, determine its economical remaining service life, and schedule routine maintenance and repair so as to minimize total operating costs without endangering public safety. The report is developed around the following specific research objectives: (1) Identify mathematical models to evaluate degradation in strength of navigation structures over time in terms of initial construction conditions, servicc load history, and aggressive environmental factors. (2) Develop a methodology to assess the probability that structural capacity has degraded below a specified level, taking into account initial conditions of the structure, service load history and structural aging, and deterioration. (3) Examine the role played by peridic inspection, nondestructive evaluation and maintenance in maintaining reliability and minimizing overall costs during a projected service period. This feasibility study is based on a review, synthesis and interpretation of existing procedures and data in the structural engineering, material science, and structural reliability literature. It provides a prospectus for subsequent research on reliabiity-based evaluation of navigation structures, some of which is initiating. (MM)

Based on historical data, a large percentage of U.S. military systems struggle to achieve their reliability requirements, resulting in significant penalties, such as decreased system availability, increased life-cycle costs, and schedule delays. These impacts are all applicable to studies of Risk Assessment and Analysis of Alternatives (AoA) which assess technical, schedule, and cost risks. In order to effectively analyze the reliability risks for programs of interest in a Risk Assessment or AoA, a new approach has been developed. The recently adopted approach consists of four separate techniques that can be used individually or collectively to inform decision makers and positively improve defense acquisition: 1. Assess the reliability estimates of similar systems to gauge the feasibility of the reliability requirement and the likelihood of achieving it. 2. Conduct an assessment using the U.S. Army Materiel Systems Analysis Activity (AMSAA) Reliability Scorecard to determine the adequacy of the overall reliability program through a quantitative risk score. 3. Create a realistic Reliability Growth Planning Curve (RGPC) using AMSAA s Planning Model based on Projection Methodology (PM2) and gauge the associated risks using AMSAA s RGPC Risk Assessment Matrix. 4. Examine the impact of the reliability requirement on test duration and Operations & Support (O&S) life-cycle costs.

Based on historical data, a large percentage of U.S. military systems struggle to achieve their reliability requirements, resulting in significant penalties, such as decreased system availability, increased life-cycle costs, and schedule delays. These impacts are all applicable to studies of Risk Assessment and Analysis of Alternatives (AoA) which assess technical, schedule, and cost risks. In order to effectively analyze the reliability risks for programs of interest in a Risk Assessment or AoA, a new approach has been developed. The recently adopted approach consists of four separate techniques that can be used individually or collectively to inform decision makers and positively improve defense acquisition: 1. Assess the reliability estimates of similar systems to gauge the feasibility of the reliability requirement and the likelihood of achieving it. 2. Conduct an assessment using the U.S. Army Materiel Systems Analysis Activity (AMSAA) Reliability Scorecard to determine the adequacy of the overall reliability program through a quantitative risk score. 3. Create a realistic Reliability Growth Planning Curve (RGPC) using AMSAA s Planning Model based on Projection Methodology (PM2) and gauge the associated risks using AMSAA s RGPC Risk Assessment Matrix. 4. Examine the impact of the reliability requirement on test duration and Operations & Support (O&S) life-cycle costs.

The Aircraft Structural Reliability and Risk Handbook provides: a) A reference on basic statistics, probability, and reliability techniques required for conducting structural risk and reliability analyses, and b) Illustrative examples of how to apply these techniques to problems involving the nucleation and growth of fatigue cracks in metallic airframe structure. This particular volume describes the fundamentals of probabilistic analysis and structural reliability analysis for the next flight.

Aircraft structural risk and reliability analysis has gained considerable interest in the area of aircraft structural integrity and fleet management in recent times. In this report, a literature review of the current approaches and methodologies that have been utilised in the area of structural risk and reliability analysis for aircraft structures and components is conducted. The structural risk and reliability approach discussed here deals mainly with the probability of failure due to aircraft structural fatigue. It reviews the engineering techniques and probabilistic methodologies that have been reported in the literature. It also discuss the advantages, disadvantage and the limitations of this approach and the reason for its need in aircraft structural and component integrity. The application of structural risk and reliability analysis is not limited to structural fatigue problem, its implication in areas other than airframe and component fatigue are also presented. This review shows that risk and reliability analysis can be a very useful tool for fleet management and it has potential implications for structural design.

Aircraft structural risk and reliability analysis has gained considerable interest in the area of aircraft structural integrity and fleet management in recent times. In this report, a literature review of the current approaches and methodologies that have been utilised in the area of structural risk and reliability analysis for aircraft structures and components is conducted. The structural risk and reliability approach discussed here deals mainly with the probability of failure due to aircraft structural fatigue. It reviews the engineering techniques and probabilistic methodologies that have been reported in the literature. It also discuss the advantages, disadvantage and the limitations of this approach and the reason for its need in aircraft structural and component integrity. The application of structural risk and reliability analysis is not limited to structural fatigue problem, its implication in areas other than airframe and component fatigue are also presented. This review shows that risk and reliability analysis can be a very useful tool for fleet management and it has potential implications for structural design.

This document, Bayesian Inference for NASA Probabilistic Risk and Reliability Analysis, is intended to provide guidelines for the collection and evaluation of risk and reliability-related data. It is aimed at scientists and engineers familiar with risk and reliability methods and provides a hands-on approach to the investigation and application of a variety of risk and reliability data assessment methods, tools, and techniques. This document provides both: A broad perspective on data analysis collection and evaluation issues. A narrow focus on the methods to implement a comprehensive information repository. The topics addressed herein cover the fundamentals of how data and information are to be used in risk and reliability analysis models and their potential role in decision making. Understanding these topics is essential to attaining a risk informed decision making environment that is being sought by NASA requirements and procedures such as 8000.4 (Agency Risk Management Procedural Requirements), NPR 8705.05 (Probabilistic Risk Assessment Procedures for NASA Programs and Projects), and the System Safety requirements of NPR 8715.3 (NASA General Safety Program Requirements).

This document, Bayesian Inference for NASA Probabilistic Risk and Reliability Analysis, is intended to provide guidelines for the collection and evaluation of risk and reliability-related data. It is aimed at scientists and engineers familiar with risk and reliability methods and provides a hands-on approach to the investigation and application of a variety of risk and reliability data assessment methods, tools, and techniques. This document provides both: A broad perspective on data analysis collection and evaluation issues. A narrow focus on the methods to implement a comprehensive information repository. The topics addressed herein cover the fundamentals of how data and information are to be used in risk and reliability analysis models and their potential role in decision making. Understanding these topics is essential to attaining a risk informed decision making environment that is being sought by NASA requirements and procedures such as 8000.4 (Agency Risk Management Procedural Requirements), NPR 8705.05 (Probabilistic Risk Assessment Procedures for NASA Programs and Projects), and the System Safety requirements of NPR 8715.3 (NASA General Safety Program Requirements).

The Johnson Space Center (JSC) Safety & Mission Assurance (S&MA) Directorate s Risk and Reliability Analysis Group provides both mathematical and engineering analysis expertise in the areas of Probabilistic Risk Assessment (PRA), Reliability and Maintainability (R&M) analysis, and data collection and analysis. The fundamental goal of this group is to provide National Aeronautics and Space Administration (NASA) decisionmakers with the necessary information to make informed decisions when evaluating personnel, flight hardware, and public safety concerns associated with current operating systems as well as with any future systems. The Analysis Group includes a staff of statistical and reliability experts with valuable backgrounds in the statistical, reliability, and engineering fields. This group includes JSC S&MA Analysis Branch personnel as well as S&MA support services contractors, such as Science Applications International Corporation (SAIC) and SoHaR. The Analysis Group s experience base includes nuclear power (both commercial and navy), manufacturing, Department of Defense, chemical, and shipping industries, as well as significant aerospace experience specifically in the Shuttle, International Space Station (ISS), and Constellation Programs. The Analysis Group partners with project and program offices, other NASA centers, NASA contractors, and universities to provide additional resources or information to the group when performing various analysis tasks. The JSC S&MA Analysis Group is recognized as a leader in risk and reliability analysis within the NASA community. Therefore, the Analysis Group is in high demand to help the Space Shuttle Program (SSP) continue to fly safely, assist in designing the next generation spacecraft for the Constellation Program (CxP), and promote advanced analytical techniques. The Analysis Section s tasks include teaching classes and instituting personnel qualification processes to enhance the professional abilities of our analysts as well as performing major probabilistic assessments used to support flight rationale and help establish program requirements. During 2008, the Analysis Group performed more than 70 assessments. Although all these assessments were important, some were instrumental in the decisionmaking processes for the Shuttle and Constellation Programs. Two of the more significant tasks were the Space Transportation System (STS)-122 Low Level Cutoff PRA for the SSP and the Orion Pad Abort One (PA-1) PRA for the CxP. These two activities, along with the numerous other tasks the Analysis Group performed in 2008, are summarized in this report. This report also highlights several ongoing and upcoming efforts to provide crucial statistical and probabilistic assessments, such as the Extravehicular Activity (EVA) PRA for the Hubble Space Telescope service mission and the first fully integrated PRAs for the CxP's Lunar Sortie and ISS missions.

The focus of the NASA 'Space Flight Risk Data Collection and Analysis' project was to acquire and evaluate space flight data with the express purpose of establishing a database containing measurements of specific risk assessment - reliability - availability - maintainability - supportability (RRAMS) parameters. The developed comprehensive RRAMS database will support the performance of future NASA and aerospace industry risk and reliability studies. One of the primary goals has been to acquire unprocessed information relating to the reliability and availability of launch vehicles and the subsystems and components thereof from the 45th Space Wing (formerly Eastern Space and Missile Command -ESMC) at Patrick Air Force Base. After evaluating and analyzing this information, it was encoded in terms of parameters pertinent to ascertaining reliability and availability statistics, and then assembled into an appropriate database structure.

The focus of the NASA 'Space Flight Risk Data Collection and Analysis' project was to acquire and evaluate space flight data with the express purpose of establishing a database containing measurements of specific risk assessment - reliability - availability - maintainability - supportability (RRAMS) parameters. The developed comprehensive RRAMS database will support the performance of future NASA and aerospace industry risk and reliability studies. One of the primary goals has been to acquire unprocessed information relating to the reliability and availability of launch vehicles and the subsystems and components thereof from the 45th Space Wing (formerly Eastern Space and Missile Command -ESMC) at Patrick Air Force Base. After evaluating and analyzing this information, it was encoded in terms of parameters pertinent to ascertaining reliability and availability statistics, and then assembled into an appropriate database structure.

The focus of the NASA 'Space Flight Risk Data Collection and Analysis' project was to acquire and evaluate space flight data with the express purpose of establishing a database containing measurements of specific risk assessment - reliability - availability - maintainability - supportability (RRAMS) parameters. The developed comprehensive RRAMS database will support the performance of future NASA and aerospace industry risk and reliability studies. One of the primary goals has been to acquire unprocessed information relating to the reliability and availability of launch vehicles and the subsystems and components thereof from the 45th Space Wing (formerly Eastern Space and Missile Command -ESMC) at Patrick Air Force Base. After evaluating and analyzing this information, it was encoded in terms of parameters pertinent to ascertaining reliability and availability statistics, and then assembled into an appropriate database structure.

One way to stability analysis of tunnel is to examine the convergence and radius of the plastic zone around it. On the other hand, uncertainties in the design parameters lead to the evaluation of the safety of structures using probabilistic and reliability methods. In this research was presented a methodology for stability analysis of two tunnels (under different conditions), by Hock-Brown and Mohr-Coulomb theory using robust reliability methods including: first order method (FORM), second order method (SORM) and Monte Carlo simulation in new RT and @Risk software. After probabilistic modeling in these two software, the results of the analysis show that the second order reliability method is more accurate than the first order method in more complex limit state functions. Also, at high values ​​of failure probability, first order and Monte Carlo simulation methods provide more realistic outputs and at low values ​​of failure probability, Monte Carlo simulation method is not recommended. In addition, the tunnel without pressure has a high probability of failure (24%), so that providing a support with 0.12 MPa pressure is efficient.

One way to stability analysis of tunnel is to examine the convergence and radius of the plastic zone around it. On the other hand, uncertainties in the design parameters lead to the evaluation of the safety of structures using probabilistic and reliability methods. In this research was presented a methodology for stability analysis of two tunnels (under different conditions), by Hock-Brown and Mohr-Coulomb theory using robust reliability methods including: first order method (FORM), second order method (SORM) and Monte Carlo simulation in new RT and @Risk software. After probabilistic modeling in these two software, the results of the analysis show that the second order reliability method is more accurate than the first order method in more complex limit state functions. Also, at high values ​​of failure probability, first order and Monte Carlo simulation methods provide more realistic outputs and at low values ​​of failure probability, Monte Carlo simulation method is not recommended. In addition, the tunnel without pressure has a high probability of failure (24%), so that providing a support with 0.12 MPa pressure is efficient.