Design Assurance Research Articles

Design Assurance Strategy and Toolset for Partially Reconfigurable FPGA Systems

The growth of the Reconfigurable Computing (RC) systems community exposes diverse requirements with regard to functionality of Electronic Design Automation (EDA) tools. Low-level design tools are increasingly required for RC bitstream debugging and IP core design assurance, particularly in multiparty Partially Reconfigurable (PR) designs. While tools for low-level analysis of design netlists do exist, there is increasing demand for automated and customisable bitstream analysis tools. This article discusses the need for low-level IP core verification within PR-enabled FPGA systems and reports FDAT (FPGA Design Analysis Tool), a versatile, modular and open tools framework for low-level analysis and verification of FPGA designs. FDAT provides a set of high-level Application Programming Interfaces (APIs) abstracting the Xilinx FPGA fabric, the implemented design (e.g., placed and routed netlist) and the related bitstream. A lightweight graphic front-end allows custom visualisation of the design within the FPGA fabric. The operation of FDAT is governed by “recipe” scripts which support rapid prototyping of the abstract algorithms for system-level design verification. FDAT recipes, being Python scripts, can be ported to embedded FPGA systems, for example, the previously reported Secure Reconfiguration Controller (SeReCon) which enforces an IP core spatial isolation policy in order to provide run-time protection to the PR system. The paper illustrates the application of FDAT for bit-pattern analysis of Virtex-II Pro and Virtex-5 inter-tile routing and verification of the spatial isolation between designs.

Validation Testing of Drift Reduction Technology Testing Protocol

Abstract A number of pesticide application technologies offer the potential to reduce spray drift from pesticide applications. However, limited information exists on the effectiveness of these technologies in reducing spray drift. Working with a stakeholder technical panel under EPA’s Environmental Technology Council, the Office of Pesticide Programs in EPA has developed and is in the process of validating a testing protocol to verify the effectiveness of drift reduction technologies (DRTs). The DRT testing protocol was adapted from standard test methods and regulatory methods used in other countries and describes the testing approach that will be used to generate high-quality, peer-reviewed data for DRTs, including test design and quality assurance aspects. Both low-speed and high-speed wind tunnel tests were completed using a reference nozzle and two test nozzles to evaluate the performance of the generic DRT testing protocol. By Summer 2010, EPA anticipates to finalize this testing protocol based on the test results performed by EPA and other stakeholders. As a next step, EPA intends to encourage equipment manufacturers to voluntarily use the protocol for testing their equipment. Tested technologies that are proven to significantly reduce spray drift may be considered for addition to pesticide product labels by pesticide registrants and by EPA in its risk assessment and management decisions for the registration of new pesticide and uses and registration review (reevaluation) of currently registered pesticides. Pesticide product labels citing the use of DRTs could have reduced restrictions for applications, provide applicators with greater flexibility, and result in less off-target pesticide deposition. This paper will provide an update of EPA’s efforts to validate the DRT testing protocol and discuss future plans for using a validated protocol in evaluating DRTs in an effort to reduce load from unintended spray drift of pesticides in the environment.

중형항공기 설계검증·인프라구축과 인증기개발의 경제적 타당성 분석

항공기 설계검증 체계를 갖추기 위한 투자 및 인프라개발, 그리고 이 과정에 동반되는 항공기개발의 경제적인 타당성을 분석하였다. 투자와 항공기 양산판매만을 고려한 현금흐름분석에서는 음의 순현재가치가 산정되어 경제적 타당성이 부인되었으나, 수출효과, 수입대체효과 및 사고감소효과를 감안할 때에는 순편익이 투자액의 3-5배에 달하는 것으로 평가되었다. 편익의 전유성이 매우 낮다는 점을 감안할 때 이 투자는 정부가 주체가 되어 실행하여야 하며, 재정지출의 경제적 타당성이 충분한 것으로 확인되었다. We analyse benefits and costs of investment on the assurance of aircraft design and development of related infrastructure. Although the discounted cash flow from the sales of aircrafts is found to be smaller than the amount of required investment, the net present value considering the effects of export increase, import substitution, and the accident cost reduction is very high. This justifies governmental investment, for the effects are not easily appropriated by private investors.

Methods for simulating and optimizing molded micro components and systems

Casting production of metallic and ceramic micro components is still in the research phase, and the components obtained with the current technologies are suffering of a certain lack of reproducibility. Within the scope of Collaborative Research Center 499 “Design, Production and Quality Assurance of Molded micro components made of Metallic and Ceramic Materials”, basics in a persistent process chain for micro components are acquired. The development, process preparation, mass production and material and components behavior investigation is understood under consistent chain. This work presents computer simulation based methods that contribute to optimize micro molded systems on both a component and a system basis. The introduction of such methods allows studying the behavior of components and systems with regard to their grain structure and the wide geometric tolerances required.

Hardware certification for real-time safety-critical systems: State of the art

This paper discusses issues related to the RTCA document DO-254 Design Assurance Guidance for Airborne Electronic Hardware and its consequences for hardware certification. In particular, problems related to circuits’ compliance with DO-254 in avionics and other industries are considered. Extensive literature review of the subject is given, including current views on and experiences of chip manufacturers and EDA industry with qualification of hardware design tools, including formal approaches to hardware verification. Some results of the authors’ own study on tool qualification are presented.

HE75 Standard Tapped as Vital New Practical Resource

When Craig Mitchell used to have a specific design question about human factors, he would usually search on Google for resources.Now he plans to turn to AAMI's new human factors standard HE75, Human factors engineering—Design of medical devices, a virtual encyclopedia of human factors information and design specifics that was released earlier this year. The clinical engineers, biomedical equipment technicians, regulators, and students—covers a variety of topics, such as visual displays, software-use interface, packaging design, usability testing, and user documentation.The standard can help in the design of products, whether it's making a device easier to use or creating a better alarm.“I plan to use HE75 to validate new product design currently in development and as a resource for future decisions” says Mitchell, the user experience design manager for PatientSafe Solutions Inc. in San Diego.Although HE75 purchasers haven't been able to use the standard on new product development yet, they have already planned how HE75 will change existing processes regarding human factors and validation.“We are in the process of updating our design validation process flow, and are making adjustments based on information within HE75,” says Glen Wagner, director of design assurance with Intel Digital Health Group in Oregon.“The primary benefit so far is being able to use this document to build up the foundation of our human factors processes to ensure conformance with IEC 62366,i ” says Wagner. “There are many known good approaches to user interaction that can be applied in our products.”While many HE75 users are still getting familiar with the standard, they are confident about its benefits, including creating a “one-stop shop” of human factors information.

Certification of software for real-time safety-critical systems: state of the art

This paper presents an overview and discusses the role of certification in safety-critical computer systems focusing on software, and partially hardware, used in the civil aviation domain. It discusses certification activities according to RTCA DO-178B “Software Considerations in Airborne Systems and Equipment Certification” and touches on tool qualification according to RTCA DO-254 “Design Assurance Guidance for Airborne Electronic Hardware.” Specifically, certification issues as related to real-time operating systems and programming languages are reviewed, as well as software development tools and complex electronic hardware tool qualification processes are discussed. Results of an independent industry survey done by the authors are also presented.

Antecedent of brand trust in online tertiary education: A Malaysian and Singapore perspective

Trust decreases the perceived risk of using a service. Since online learners have no direct contact with the education providers, trust plays an important role in an online tertiary setting. However, there is a void of study of trust within the context of consumer-brand relation in tertiary education. In a review of the literature, hypotheses are developed that suggest that the antecedent of brand trust, operating as quality cues in online tertiary education are related to institutional and courseware design assurance factors, site (Web) quality and public awareness. A conceptual model summarizing the hypotheses is subsequently validated in an empirical study reported here.

Performance evaluation for pinhole collimators of small gamma camera by MTF and NNPS analysis: Monte Carlo simulation study

Presently, the gamma camera system is widely used in various medical diagnostic, industrial and environmental fields. Hence, the quantitative and effective evaluation of its imaging performance is essential for design and quality assurance. The National Electrical Manufacturers Association (NEMA) standards for gamma camera evaluation are insufficient to perform sensitive evaluation. In this study, modulation transfer function (MTF) and normalized noise power spectrum (NNPS) will be suggested to evaluate the performance of small gamma camera with changeable pinhole collimators using Monte Carlo simulation. We simulated the system with a cylinder and a disk source, and seven different pinhole collimators from 1- to 4-mm-diameter pinhole with lead. The MTF and NNPS data were obtained from output images and were compared with full-width at half-maximum (FWHM), sensitivity and differential uniformity. In the result, we found that MTF and NNPS are effective and novel standards to evaluate imaging performance of gamma cameras instead of conventional NEMA standards.

Hardware Certification for Safety-Critical Real-Time Systems

Abstract This paper discusses issues related to the RTCA document DO-254 Design Assurance Guidance for Airborne Electronic Hardware and its consequences for hardware certification. In particular, problems related to circuits’ compliance with DO-254 in avionics and other industries are considered. Extensive literature review of the subject is given, including current views on and experiences with qualification of hardware design tools. Some results of the authors’ own study on tool qualification are presented.

Optimization of a pipe end upsetting process

This paper discusses the application of Design of Experiments, Response Surface Methodology and Robust Optimization techniques for efficient optimization of pipe end upsetting with a non-uniform and transient temperature field. First, target pipe end shape and objective functions are defined, and constraints on the final shape, forging pressures, temperatures and strain rates are specified. Second, parametric initial work piece shape and initial temperature distributions are defined. Material data are obtained from independent compression tests. Third, a Box-Behnken experimental design (BBD) is defined for a set of shape and temperature variables. A set of ABAQUS simulations is run according to the BBD. The results from the simulation runs are processed by a MATLAB-script. The script calculates regression relations for all essential responses and estimates the value of the object functions and constraints in the entire design space. Further, it performs both standard and robust constrained optimization. The robust optimization considers the effects of variability in design variables. Finally, MATLAB plots several 2D cross-sections of objective and constraints functions in the multi-dimensional design space. Such process windows make prediction of the capability of the upsetting process possible and are very valuable input to the design and quality assurance work.

CAD tools integration for robot kinematics design assurance with case studies on PUMA robots

PurposeIn this paper, a CAD‐based integration method for analyzing and verifying robotic mechanisms design is proposed. The work is motivated by the fact that current structural design of complex mechanisms still requires substantial efforts of human intervention even with CAD assistance.Design/methodology/approachIt is accomplished by blending the unique capabilities of two popular engineering CAD packages, namely, the mathematical computations in Matlab and the virtual prototyping functions in Pro/Mechanica. Here we take advantage of the numerical computation capability of Matlab to complete the first portion of design tasks. Consequently, the proposed integration of these two CAD tools comes into play, which involves writing the joint angle values calculated from Matlab to.tab text files first. These.tab files are then directly used as the input for joint angles' drivers in Pro/Mechanica's virtual motion analysis function.FindingsThe proposed method realizes design automation of robotic mechanisms and provides design flexibility by allowing the designers to change designated critical design parameters rather easily and quickly within the blended Matlab and Pro/Mechanica design environment. The results demonstrate that the design process of robot manipulators can be largely automated by using the integrated CAD means proposed in this paper. Thus, the contributions of the work in design cost saving, performance verification, structural flexibility, as well as assembly dynamics are all evidenced.Research limitations/implicationsFuture research will consider the generalization of the methodology to include dynamics aspect for design of complicated mechanisms.Practical implicationsTo show the efficiency and effectiveness of the proposed method, several case studies are conducted aimed at the design analysis and verification of a six degree‐of‐freedom PUMA industrial robot.Originality/valueThe proposed method realizes design automation of robotic mechanisms and provides design flexibility by allowing the designers to change designated critical design parameters rather easily and quickly within the blended Matlab and Pro/Mechanica design environment. As a result, it greatly reduces total design cycle time of complex mechanisms.

Recognizing features from orthographic images using neural networks: a framework for CADCAM and AVI integration

In order to satisfy the current market demands for shorter lead-time and high quality products manufacturing enterprises have to integrate their design, production and quality assurance functions. In a computerized environment these functions are manifested in CAD, CAM and AVI respectively. In the recent past, much success has been achieved in integrating CAD and CAM. It is widely accepted that feature recognition systems, both 2D and 3D, have been one of the main contributors to CADCAM integration. However the existing feature recognition systems could not link CADCAM and AVI and hence could not close the manufacturing loop that ensures the production of designer intended features. This is mainly because the input formats of existing feature recognition systems and AVI systems have been different in format and structure. The system described in this paper attempts to redress this deficit at least partially by using a monochrome bitmap as a generic input, to which both CAD models and vision images could be converted. Hence the input to the system takes a form of third angle orthographic views, however, without hidden lines in order to facilitate dealing with vision images. This, in turn, augments difficulty faced in recognizing features. To overcome this difficulty, the help of evolutionary computing and artificial intelligence is sought in this system. This paper outlines the basis of a 2D feature recognition system that uses artificial neural networks along with a chain code method for eliciting feature information from monochrome bitmap of either vision images or CAD inputs hence providing a generic framework to integrate CADCAM and AVI. With further improvement to deal with geometry of the features, annotations and symbols this system could also help to salvage the massive store of engineering knowledge that exists in 2D form.

Reverse Engineering of Software Life Cycle Data In Certification Projects

Some applicants, developers, and commercial-off-the-shelf (COTS) software vendors have proposed reverse engineering as an approach for satisfying RTCS/DO-178B objectives for airborne software. RTCA/DO-178B, Software Considerations in Airborne Systems and Equipment Certification, serves as means of compliance for most airborne software in civil aircraft. DO-178B defines reverse engineering as the method of extracting software design information from source code and provides guidance particular to reverse engineering, when it is used to upgrade a development baseline. For purposes of this paper, reverse engineering is an approach for creating software life cycle data that did not originally exist, cannot be found, is not adequate, or is not available to a developer in order to meet applicable DO-178B objectives. Reverse engineering is not just generation of data - rather it is a process to assure that data is correct, software functionality is understood and well documented and software functions as intended and required by system. Reverse engineering is not, as some software developers propose, just an effort to generate software life cycle data without intent to build in quality and resulting design assurance. This article explores reverse engineering in airborne software projects, by explaining a definition for certification domain, describing motivation for its use, and documenting certification concerns. Two actual cases of reverse engineering are also described to illustrate certification concerns in real projects.

Quality assurance in micro production

Quality assurance is essential for an efficient support of all developing and manufacturing processes and activities with the forefront objective to reach robust processes with a high throughput of parts meeting their functional requirements. Due to the lack of a broad base of experiences regarding the still developing manufacturing technologies in micro production an adequate quality assurance plays an even more important role in order to efficiently support the transition of micro production processes from non-robust to stable processes. Thereby, quality assurance faces particular challenges in micro production, which render a reasonable application of common quality methods difficult or even impossible. Consequently, it is essential to develop new concepts or adjust widely applied quality assurance methods in order to support and continuously improve the development- and manufacturing processes in micro production. Within the scope of the Collaborative Research Center (SFB) 499 “Design, production and quality assurance of primary shaped micro components manufactured in ceramic and metallic materials” the approach of the subproject working on the topic quality assurance is threefold: (i) An efficient and process-accompanying information management has been implemented and will be enhanced further on. (ii) Specifically adjusted preventive methods of quality assurance have been developed and applied. (iii) In order to implement an efficient operational quality assurance performance data of the manufacturing processes has been collected and provided. In the future this supply of data will be used to control and improve the manufacturing processes.

Preventive Quality Assurance in the Context of Micromechanical Component Fabrication by Microfeatures

This article presents an approach of the Microfeature Catalog as an information database that is structured by features and that operates as the basis for preventive and nonpreventive quality assurance information. The microfeature concept is adapted and evaluated in the specific environment of the fabrication of micromechanical components. The development of microparts demands the further development of the new manufacturing technologies, as well as an appropriated development of the accompanying processes like quality assurance. A closed information loop between design, manufacturing, and quality assurance is realized.

Assurance in clinical trial design

Conventional clinical trial design involves considerations of power, and sample size is typically chosen to achieve a desired power conditional on a specified treatment effect. In practice, there is considerable uncertainty about what the true underlying treatment effect may be, and so power does not give a good indication of the probability that the trial will demonstrate a positive outcome. Assurance is the unconditional probability that the trial will yield a ‘positive outcome’. A positive outcome usually means a statistically significant result, according to some standard frequentist significance test. The assurance is then the prior expectation of the power, averaged over the prior distribution for the unknown true treatment effect. We argue that assurance is an important measure of the practical utility of a proposed trial, and indeed that it will often be appropriate to choose the size of the sample (and perhaps other aspects of the design) to achieve a desired assurance, rather than to achieve a desired power conditional on an assumed treatment effect. We extend the theory of assurance to two-sided testing and equivalence trials. We also show that assurance is straightforward to compute in some simple problems of normal, binary and gamma distributed data, and that the method is not restricted to simple conjugate prior distributions for parameters. Several illustrations are given. Copyright © 2005 John Wiley & Sons, Ltd.

Red Team Performance for Improved Computer Security

This research attempts to develop a human factors understanding of red team assessment strategies in computer and information security. Red teaming is an advanced form of assessment that can be used to identify weaknesses in a variety of security systems. The purpose of this research is to identify and define the various dimensions of red team effectiveness with the aim of improving red team performance. A study of a red team was conducted in collaboration with Sandia National Laboratories Information Design Assurance Red Team (IDART). The design of the study included semi-structured individual interviews and focus groups with red team members and observation of red team practices. The analysis yielded various dimensions of red team effectiveness from the customer, management, individual, and team member perspectives.

Mechanical Design Analysis and Test in Support of the Market Introduction of a New Vehicle

This paper reports results from a stress, acoustics and vibration investigation of the ride and driveline components of a new 2-seater sports car. The work was aimed at giving design assurance information to designers and vehicle engineers working to compressed timescales. The paper focuses on two particular areas: design of the power train for NVH refinement, and design analysis of a suspension wishbone. In the first case, a dynamic model of drive shaft torsion effects was created to understand design relationships needed for high power, high torque performance car. In the second case, an investigation was made into the integrity of a suspension wishbone component when gauge thickness was reduced from 3 mm to 2 mm. The work described was carried out in a joint industry academic venture sponsored by Knowledge Transfer Partnership (KTP). It is from this background that the authors give some perspectives on vehicle development.

Integrative quality assurance of micro-parts using Microfeatures

The article introduces the “Microfeature Catalogue” as an information database that is structured by Microfeatures and can be used for preventive and non-preventive quality assurance. The Microfeature conception is adapted and evaluated in the specific fabrication environment of micro mechanical components. The production of micro parts demands a further development of the new fabrication technologies on the one hand and an appropriate development of the concomitant processes such as the quality assurance process on the other hand. A coherent information cycle between design, fabrication and quality assurance is put into practice.