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Video

A Quantitative Risk Analysis for AeroMACS Network Security in SESAR

2012-03-16
The growing need for an efficient worldwide airspace system management, generated by an increasing traffic load, requires new capabilities for air-ground data communication technologies. In order to cope with these requirements, the Federal Aviation Administration (FAA), EUROCONTROL, and the International Civil Aviation Organization (ICAO) have jointly made specific recommendations for candidate technologies for the airport surface communication network. In the SESAR project, the Aeronautical Mobile Airport Communication System (AeroMACS) technology is being developed in such a way to provide next generation broadband and wireless data communications for airport surface applications (i.e. Air Traffic Control ? ATC, Airline Operational Communications ? AOC, and surface vehicles services).
Video

Review and Assessment of the ISO 26262 Draft Road Vehicle - Functional Safety

2012-09-18
ISO 26262 is the first comprehensive automotive safety standard that addresses the safety of the growing number of electric/electronic and software intensive features in today's road vehicles. This paper assesses the standard's ability to provide safety assurance. The strengths of the standard are: (1) emphasizing safety management and safety culture; (2) prescribing a system engineering development process; (3) setting up a framework for hazard elimination early in the design process; (4) disassociating system safety risk assessment from component probabilistic failure rate. The third and fourth strengths are noteworthy departure from the philosophy of IEC61508. This standard has taken much-needed and very positive steps towards ensuring the functional safety of the modern road vehicles. SAE publications from industry show a lot of enthusiasm towards this standard.
Video

Automotive Functional Safety Standard ISO 26262 and the Current Challenges

2021-03-20
The ISO 26262, titled "Road vehicles - Functional safety," is a Functional Safety standard that gives a guidance to reduce the risks to tolerable level by providing feasible requirements and processes. This standard is an adaptation of the Functional Safety standard IEC 61508 for Automotive Electrical/Electronic and programmable electronic Systems. The standard covers the development of safety-related electrical, electronic and programmable electronics systems in the road vehicles. It will have a significant impact on the way such systems are designed, developed, integrated and validated for safety. Functional safety of embedded systems has become an integral part in automotive engineering activities due to the recently released safety standard ISO 26262. One main challenge is to perform development activities compliant to the standard and provide the respective documentation.
SAE MOBILUS Subscription

Wiley Cyber Security Collection Add-On

2018-03-23
As an annual subscription, the Wiley Cyber Security Collection Add-On is available for purchase along with one or both of the following: Wiley Aerospace Collection Wiley Automotive Collection The titles from the Wiley Cyber Security Collection are included in the SAE MOBILUS® eBook Package. Titles: Network Forensics Penetration Testing Essentials Security in Fixed and Wireless Networks, 2nd Edition The Network Security Test Lab: A Step-by-Step Guide Risk Centric Threat Modeling: Process for Attack Simulation and Threat Analysis Applied Cryptography: Protocols, Algorithms and Source Code in C, 20th Anniversary Edition Computer Security Handbook, Set, 6th Edition Threat Modeling: Designing for Security Other available Wiley collections: Wiley SAE MOBILUS eBook Package Wiley Aerospace Collection Wiley Automotive Collection Wiley Computer Systems Collection Add-On (purchasable with the Wiley Aerospace Collection and/or the Wiley Automotive Collection)
Technical Paper

A Contribution to Risk Analysis and the Characteristics of Truck Accidents

1984-01-01
845017
The subject of research into truck accidents with a view to making safety modifications to trucks is steadily gaining in importance. In the light of newly compiled truck accident material comprising 2000 cases from 1979 to 1983 the problem of truck accidents can be assessed comprehensively. This study covers truck accidents with pedestrians, bicycles and motorcycles, cars, truck/truck collisions and single-truck accidents. Because all accident groups and their percentage weighting according to real life are considered, it is possible to transfer the results to the general accident occurrence. The internal structure of the accident groups is contrasted with the official accident statistics in significant accident parameters. The frequencies of essential parameters, i.e. the kind of collision, the type of accident and the risk for the truck occupants and the other traffic participants involved are indicated.
Technical Paper

Quantified Risk in a Democratic Society

1984-04-01
840870
THE EMPHASIS IN THIS ANALYSIS is on the word “democratic”. We live in a democratic society, and we intend to continue to do so. If risk analysis is to have a useful contribution to our society it must fit itself into its democratic decision making structure. If necessary, it must subordinate itself to this democratic tradition. The subject being considered is complex. In order to provide some coherence to the presentation, the following approach will be adopted: First, the societal framework will be mapped out. Second, quantified risk analysis itself will be defined. Third, its status will be analyzed by means of a case study. Fourth, some conclusions will be drawn.
Technical Paper

An Analytical Methodology for Engine Gear Rattle and Whine Assessment and Noise Simulation

2019-04-02
2019-01-0799
In this paper, a CAE methodology based on a multiphysics approach for engine gear noise evaluation is reviewed. The method comprises the results and outputs from several different analytical domains to perform the noise risk assessment. The assessment includes the source-path analysis of the gear-induced rattling and whining noise. The vibration data from the exterior surface of the engine is extended through acoustic analysis to perform the engine noise simulation and to identify acoustic hot spots contributing to the noise. The study includes simulations under different engine loading conditions with results presented in both time and frequency domains. Various sensitivity analyses involving different gear geometries and micro-geometries are investigated as well. Finally, the simulation results from three different engines are compared vis-a-vis.
Journal Article

A Method to Estimate Regression Model Confidence Interval and Risk of Artificial Neural Network Model

2022-05-17
Abstract Artificial neural networks (ANNs) have found increasing usage in regression problems because of their ability to map complex nonlinear relationships. In recent years, ANN regression model applications have rapidly increased in the engine calibration and controls area. The data used to build ANN models in engine calibration and controls area generally consists of noise due to instrument error, sensor precision, human error, stochastic process, etc. Filtering the data helps in reducing noise due to instrument error, but noise due to other sources still exist in data. Furthermore, many researchers have found that ANNs are susceptible to learning from noise. Also ANNs cannot quantify the uncertainty of their output in critical applications. Hence, a methodology is developed in the present manuscript which computes the noise-based confidence interval using engine test data. Moreover, a method to assess the risk of ANN learning from noise is also developed.
Technical Paper

Fatigue Damage Prediction for Bonded Composite Repairs Applied to Metallic Aircraft Structures

2001-09-10
2001-01-2628
This paper describes the initial development of methods for predicting the fatigue life of bonded composite repairs applied to cracked aluminum aircraft structures. Bonded repairs offer great potential in stopping or slowing crack growth. The benefits of bonded repairs when compared to riveted repairs are significant, and include improvements in fatigue life, inspectability, and cost. The main barrier to the widespread use of this technology is the lack of methods for ensuring damage tolerance and durability [1–3]. In this paper, approximate analytical equations are developed to characterize both disbonding and crack growth in a repair applied to a center-cracked plate. The equations are in a form suitable for use in probabilistic risk assessments and inclusion in industry codes and standards, and have been validated against a boundary element model.
Technical Paper

Neutron Environment Calculations for Low Earth Orbit

2001-07-09
2001-01-2327
The long term exposure of astronauts on the developing International Space Station (ISS) requires an accurate knowledge of the internal exposure environment for human risk assessment and other onboard processes. The natural environment is moderated by the solar wind, which varies over the solar cycle. The HZETRN high charge and energy transport code developed at NASA Langley Research Center can be used to evaluate the neutron environment on ISS. A time dependent model for the ambient environment in low earth orbit is used. This model includes GCR radiation moderated by the Earth’s magnetic field, trapped protons, and a recently completed model of the albedo neutron environment formed through the interaction of galactic cosmic rays with the Earth’s atmosphere. Using this code, the neutron environments for space shuttle missions were calculated and comparisons were made to measurements by the Johnson Space Center with onboard detectors.
Technical Paper

A Systems Modeling Methodology for Evaluation of Vehicle Aggressivity in the Automotive Accident Environment

2001-03-05
2001-01-1172
A systems modeling approach is presented for assessment of harm in the automotive accident environment. The methodology is presented in general form and then applied to evaluate vehicle aggressivity in frontal crashes. The methodology consists of parametric simulation of several controlled accident variables, with case results weighted by the relative frequency of each specific event. A hierarchy of models is proposed, consisting of a statistical model to define the accident environment and assign weighting factors for each crash situation case, and vehicle and occupant models for kinematic simulation of crash events. Head and chest injury results obtained from simulation are converted to harm vectors, in terms of probabilistic Abbreviated Injury Scale (AIS) distributions based on previously defined risk analyses. These harm vectors are weighted by each case’s probability as defined by the statistical model, and summed to obtain a total estimate of harm for the accident environment.
Technical Paper

Integrated Systems Testing of Spacecraft

2007-07-09
2007-01-3144
How much integrated system level test should be performed on a spacecraft before it is launched? Although sometimes system test is minimized, experience shows that systems level testing should be thorough and complete. Reducing subsystem testing is a less dangerous way to save cost, since it risks finding problems later in system test, while cutting systems test risks finding them even later on orbit. Human-rated spacecraft test planning is informal, subjective, and inconsistent, and its extent is often determined by the decision maker's risk tolerance, decision-making style, and long-term or short-term view. Decisions on what to test should be guided by an overall mission cost-benefit analysis, similar to the risk analysis used to guide development efforts.
Technical Paper

Risk Assessment and Shielding Design for Long-Term Exposure to Ionizing Space Radiation

2006-07-17
2006-01-2108
NASA is now focused on the agency's vision for space exploration encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. As a result, there is a focus on long duration space missions. NASA is committed to the safety of the missions and the crew, and there is an overwhelming emphasis on the reliability issues for space missions and the habitat. The cost effective design of the spacecraft demands a very stringent requirement on the optimization process. Exposure from the hazards of severe space radiation in deep space and/or long duration missions is ‘the show stopper.’ Thus, protection from the hazards of severe space radiation is of paramount importance to the new vision. It is envisioned to have long duration human presence on the Moon for deep space exploration. As NASA is looking forward to exploration in deep space, there is a need to go beyond current technology to the technology of the future.
Technical Paper

Managing Value Stream Risk

2006-08-30
2006-01-2389
A typical risk assessment or audit used in industry today will look at a single organizations risk in an isolated business system dimension, such as the management system, product, or process deployed at a specific company. Risk must be found in both material and information flows and quantified in order to enable effective management decisions. Value Stream Risk Assessment™ (VSRA™) is a tool to identify, quantify, prioritize, and intelligently mitigate risk wherever it resides in a the Value Stream. VSRA™ has been developed to compliment Lean and Six Sigma techniques and enhances the quality audit process to provide more value to the organization.
Technical Paper

Controllability of Active Steering System Hazards: From Standards to Driving Tests

2006-04-03
2006-01-0600
When developing new automotive systems a great deal of the development effort is devoted to ensure a sufficient functional safety of the system. A question that arises during early risk analyses of such a system is that of the controllability of possible system hazards. While this question is answered in early stages very often using worst-case risk graphs, the question comes back later in a much more precise way: in case of active steering systems component failures would produce a deviation between desired and actual road wheel position, the deviation can be measured in terms of amplitude and/or time. The central question is how much deviation can be controlled by the driver? Note, that there will always be a certain, even small, deviation between desired and actual road wheel position since the steering systems controller contains feedback control algorithms aiming at minimising the regulation error but not actually making it disappear totally.
Technical Paper

Discharge of De-Icing Agents from Airports to Nearby Water Recipients in Relation to the Water Framework Directive

2007-09-24
2007-01-3350
Discharge of oxygen demanding substances like glycol, formate, acetate or ammonium may give anaerobic conditions, water with unpleasant odour/taste and appearance, as well as bacterial growth. Fish and bottom fauna may be negatively affected. Formate has the lowest oxygen demand, and will therefore be the most environmental friendly runway de-icing agent. Additives in de-icing agents may have a negative effect on the organisms living in the recipients. The only additive of environmental concern in the de-icing products used at Oslo Airport is an alcohol ethoxylate. This substance is ready biodegradable, probably not bioaccumulating, but is very toxic to aquatic organisms. An environmental risk assessment of the discharge water from the Oslo Airport concluded that the discharge would not be acute toxic for algae or crustacean in the water recipient.
Technical Paper

Improvement of Risk Assessment from Space Radiation Exposure for Future Space Exploration Missions

2007-07-09
2007-01-3116
Protecting astronauts from space radiation exposure is an important challenge for mission design and operations for future exploration-class and long-duration missions. Crew members are exposed to sporadic solar particle events (SPEs) as well as to the continuous galactic cosmic radiation (GCR). If sufficient protection is not provided the radiation risk to crew members from SPEs could be significant. To improve exposure risk estimates and radiation protection from SPEs, detailed evaluations of radiation shielding properties are required. A model using a modern CAD tool ProE™, which is the leading engineering design platform at NASA, has been developed for this purpose. For the calculation of radiation exposure at a specific site, the cosine distribution was implemented to replicate the omnidirectional characteristic of the 4π particle flux on a surface.
Technical Paper

First Results: FORAS in Operation

2007-09-17
2007-01-3881
The Flight Operations Risk Assessment System (FORAS) is a methodology for producing aviation risk models for air carriers. These risk models represent the causal risk factors and their relationships as a fuzzy expert system. Such a risk model, for Approach and Landing incident risk, has been created for EVA Airways. This paper will present some initial findings from the development and trial application period of the risk model.
Technical Paper

Managing Risk Reduction using a Relative Risk Prioritization Tool

2007-09-17
2007-01-3871
The Safety Management System (SMS) provides an environment where undesired events (proactively or reactively identified) are evaluated for the effect on safety using Risk Analysis. When the risk is evaluated, an interim risk reduction (mitigating action) may be applied to reduce the risk to a level that allows operations for a longer period before the safety issue is fully resolved. The risk assessment provides a means of evaluating the risk level and it may be difficult to quantify the “benefit” of interim mitigations that will reduce the risk. Prioritization of issues in the same risk category of the Risk Matrix is often simplified to a schedule and logistics basis of the final corrective action and often does not adequately show the benefit of the interim mitigating actions taken.
Technical Paper

Case for a Multidisciplinary Modeling Platform for Space Launch Risk Analysis

2007-09-17
2007-01-3864
With the development and licensing of inland, state-owned spaceports, and the ongoing development of several new reusable launch vehicles (RLV), the space launch industry is undergoing a significant transformation. As a result, there is a need to reevaluate current launch risk analysis methodologies and practices, which so far have revolved around the conservative casualty expectation analysis developed in the 1950s. Furthermore, an important aspect of launch risk analysis which gives rise to its complexity is its multidisciplinary nature. In analyzing such risk, the physics of and interactions between the varieties of hazards produced by launch vehicles breakups must be captured, modeled and, their effects analyzed. In this paper we discuss how a well-designed multidisciplinary modeling and analysis platform could be a significant step toward reducing the complexity just mentioned.
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