Analyzing Software Requirements Errors in Safety-Critical, Embedded Systems
NASA Technical Reports Server (NTRS)
Lutz, Robyn R.
1993-01-01
This paper analyzes the root causes of safety-related software errors in safety-critical, embedded systems. The results show that software errors identified as potentially hazardous to the system tend to be produced by different error mechanisms than non- safety-related software errors. Safety-related software errors are shown to arise most commonly from (1) discrepancies between the documented requirements specifications and the requirements needed for correct functioning of the system and (2) misunderstandings of the software's interface with the rest of the system. The paper uses these results to identify methods by which requirements errors can be prevented. The goal is to reduce safety-related software errors and to enhance the safety of complex, embedded systems.
Review of battery powered embedded systems design for mission-critical low-power applications
NASA Astrophysics Data System (ADS)
Malewski, Matthew; Cowell, David M. J.; Freear, Steven
2018-06-01
The applications and uses of embedded systems is increasingly pervasive. Mission and safety critical systems relying on embedded systems pose specific challenges. Embedded systems is a multi-disciplinary domain, involving both hardware and software. Systems need to be designed in a holistic manner so that they are able to provide the desired reliability and minimise unnecessary complexity. The large problem landscape means that there is no one solution that fits all applications of embedded systems. With the primary focus of these mission and safety critical systems being functionality and reliability, there can be conflicts with business needs, and this can introduce pressures to reduce cost at the expense of reliability and functionality. This paper examines the challenges faced by battery powered systems, and then explores at more general problems, and several real-world embedded systems.
Analyzing Software Errors in Safety-Critical Embedded Systems
NASA Technical Reports Server (NTRS)
Lutz, Robyn R.
1994-01-01
This paper analyzes the root causes of safty-related software faults identified as potentially hazardous to the system are distributed somewhat differently over the set of possible error causes than non-safety-related software faults.
Remote Diagnosis of the International Space Station Utilizing Telemetry Data
NASA Technical Reports Server (NTRS)
Deb, Somnath; Ghoshal, Sudipto; Malepati, Venkat; Domagala, Chuck; Patterson-Hine, Ann; Alena, Richard; Norvig, Peter (Technical Monitor)
2000-01-01
Modern systems such as fly-by-wire aircraft, nuclear power plants, manufacturing facilities, battlefields, etc., are all examples of highly connected network enabled systems. Many of these systems are also mission critical and need to be monitored round the clock. Such systems typically consist of embedded sensors in networked subsystems that can transmit data to central (or remote) monitoring stations. Moreover, many legacy are safety systems were originally not designed for real-time onboard diagnosis, but a critical and would benefit from such a solution. Embedding additional software or hardware in such systems is often considered too intrusive and introduces flight safety and validation concerns. Such systems can be equipped to transmit the sensor data to a remote-processing center for continuous health monitoring. At Qualtech Systems, we are developing a Remote Diagnosis Server (RDS) that can support multiple simultaneous diagnostic sessions from a variety of remote subsystems.
2017-03-20
computation, Prime Implicates, Boolean Abstraction, real- time embedded software, software synthesis, correct by construction software design , model...types for time -dependent data-flow networks". J.-P. Talpin, P. Jouvelot, S. Shukla. ACM-IEEE Conference on Methods and Models for System Design ...information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and
Development of a methodology for assessing the safety of embedded software systems
NASA Technical Reports Server (NTRS)
Garrett, C. J.; Guarro, S. B.; Apostolakis, G. E.
1993-01-01
A Dynamic Flowgraph Methodology (DFM) based on an integrated approach to modeling and analyzing the behavior of software-driven embedded systems for assessing and verifying reliability and safety is discussed. DFM is based on an extension of the Logic Flowgraph Methodology to incorporate state transition models. System models which express the logic of the system in terms of causal relationships between physical variables and temporal characteristics of software modules are analyzed to determine how a certain state can be reached. This is done by developing timed fault trees which take the form of logical combinations of static trees relating the system parameters at different point in time. The resulting information concerning the hardware and software states can be used to eliminate unsafe execution paths and identify testing criteria for safety critical software functions.
Testing of Safety-Critical Software Embedded in an Artificial Heart
NASA Astrophysics Data System (ADS)
Cha, Sungdeok; Jeong, Sehun; Yoo, Junbeom; Kim, Young-Gab
Software is being used more frequently to control medical devices such as artificial heart or robotic surgery system. While much of software safety issues in such systems are similar to other safety-critical systems (e.g., nuclear power plants), domain-specific properties may warrant development of customized techniques to demonstrate fitness of the system on patients. In this paper, we report results of a preliminary analysis done on software controlling a Hybrid Ventricular Assist Device (H-VAD) developed by Korea Artificial Organ Centre (KAOC). It is a state-of-the-art artificial heart which completed animal testing phase. We performed software testing in in-vitro experiments and animal experiments. An abnormal behaviour, never detected during extensive in-vitro analysis and animal testing, was found.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-20
... NUCLEAR REGULATORY COMMISSION [NRC-2013-0098] Embedded Digital Devices in Safety-Related Systems... (NRC) is issuing for public comment Draft Regulatory Issue Summary (RIS) 2013-XX, ``Embedded Digital... requirements for the quality and reliability of basic components with embedded digital devices. DATES: Submit...
ASSIP Study of Real-Time Safety-Critical Embedded Software-Intensive System Engineering Practices
2008-02-01
and assessment 2. product engineering processes 3. tooling processes 6 | CMU/SEI-2008-SR-001 Slide 1 Process Standards IEC/ ISO 12207 Software...and technical effort to align with 12207 IEC/ ISO 15026 System & Software Integrity Levels Generic Safety SAE ARP 4754 Certification Considerations...Process Frameworks in revision – ISO 9001, ISO 9004 – ISO 15288/ ISO 12207 harmonization – RTCA DO-178B, MOD Standard UK 00-56/3, … • Methods & Tools
Proceedings of the Twenty-Third Annual Software Engineering Workshop
NASA Technical Reports Server (NTRS)
1999-01-01
The Twenty-third Annual Software Engineering Workshop (SEW) provided 20 presentations designed to further the goals of the Software Engineering Laboratory (SEL) of the NASA-GSFC. The presentations were selected on their creativity. The sessions which were held on 2-3 of December 1998, centered on the SEL, Experimentation, Inspections, Fault Prediction, Verification and Validation, and Embedded Systems and Safety-Critical Systems.
Fault Tree Analysis Application for Safety and Reliability
NASA Technical Reports Server (NTRS)
Wallace, Dolores R.
2003-01-01
Many commercial software tools exist for fault tree analysis (FTA), an accepted method for mitigating risk in systems. The method embedded in the tools identifies a root as use in system components, but when software is identified as a root cause, it does not build trees into the software component. No commercial software tools have been built specifically for development and analysis of software fault trees. Research indicates that the methods of FTA could be applied to software, but the method is not practical without automated tool support. With appropriate automated tool support, software fault tree analysis (SFTA) may be a practical technique for identifying the underlying cause of software faults that may lead to critical system failures. We strive to demonstrate that existing commercial tools for FTA can be adapted for use with SFTA, and that applied to a safety-critical system, SFTA can be used to identify serious potential problems long before integrator and system testing.
Scheduling Real-Time Mixed-Criticality Jobs
NASA Astrophysics Data System (ADS)
Baruah, Sanjoy K.; Bonifaci, Vincenzo; D'Angelo, Gianlorenzo; Li, Haohan; Marchetti-Spaccamela, Alberto; Megow, Nicole; Stougie, Leen
Many safety-critical embedded systems are subject to certification requirements; some systems may be required to meet multiple sets of certification requirements, from different certification authorities. Certification requirements in such "mixed-criticality" systems give rise to interesting scheduling problems, that cannot be satisfactorily addressed using techniques from conventional scheduling theory. In this paper, we study a formal model for representing such mixed-criticality workloads. We demonstrate first the intractability of determining whether a system specified in this model can be scheduled to meet all its certification requirements, even for systems subject to two sets of certification requirements. Then we quantify, via the metric of processor speedup factor, the effectiveness of two techniques, reservation-based scheduling and priority-based scheduling, that are widely used in scheduling such mixed-criticality systems, showing that the latter of the two is superior to the former. We also show that the speedup factors are tight for these two techniques.
Proceedings of the Sixth NASA Langley Formal Methods (LFM) Workshop
NASA Technical Reports Server (NTRS)
Rozier, Kristin Yvonne (Editor)
2008-01-01
Today's verification techniques are hard-pressed to scale with the ever-increasing complexity of safety critical systems. Within the field of aeronautics alone, we find the need for verification of algorithms for separation assurance, air traffic control, auto-pilot, Unmanned Aerial Vehicles (UAVs), adaptive avionics, automated decision authority, and much more. Recent advances in formal methods have made verifying more of these problems realistic. Thus we need to continually re-assess what we can solve now and identify the next barriers to overcome. Only through an exchange of ideas between theoreticians and practitioners from academia to industry can we extend formal methods for the verification of ever more challenging problem domains. This volume contains the extended abstracts of the talks presented at LFM 2008: The Sixth NASA Langley Formal Methods Workshop held on April 30 - May 2, 2008 in Newport News, Virginia, USA. The topics of interest that were listed in the call for abstracts were: advances in formal verification techniques; formal models of distributed computing; planning and scheduling; automated air traffic management; fault tolerance; hybrid systems/hybrid automata; embedded systems; safety critical applications; safety cases; accident/safety analysis.
Java Source Code Analysis for API Migration to Embedded Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Winter, Victor; McCoy, James A.; Guerrero, Jonathan
Embedded systems form an integral part of our technological infrastructure and oftentimes play a complex and critical role within larger systems. From the perspective of reliability, security, and safety, strong arguments can be made favoring the use of Java over C in such systems. In part, this argument is based on the assumption that suitable subsets of Java’s APIs and extension libraries are available to embedded software developers. In practice, a number of Java-based embedded processors do not support the full features of the JVM. For such processors, source code migration is a mechanism by which key abstractions offered bymore » APIs and extension libraries can made available to embedded software developers. The analysis required for Java source code-level library migration is based on the ability to correctly resolve element references to their corresponding element declarations. A key challenge in this setting is how to perform analysis for incomplete source-code bases (e.g., subsets of libraries) from which types and packages have been omitted. This article formalizes an approach that can be used to extend code bases targeted for migration in such a manner that the threats associated the analysis of incomplete code bases are eliminated.« less
NASA Technical Reports Server (NTRS)
Joshi, Anjali; Heimdahl, Mats P. E.; Miller, Steven P.; Whalen, Mike W.
2006-01-01
System safety analysis techniques are well established and are used extensively during the design of safety-critical systems. Despite this, most of the techniques are highly subjective and dependent on the skill of the practitioner. Since these analyses are usually based on an informal system model, it is unlikely that they will be complete, consistent, and error free. In fact, the lack of precise models of the system architecture and its failure modes often forces the safety analysts to devote much of their effort to gathering architectural details about the system behavior from several sources and embedding this information in the safety artifacts such as the fault trees. This report describes Model-Based Safety Analysis, an approach in which the system and safety engineers share a common system model created using a model-based development process. By extending the system model with a fault model as well as relevant portions of the physical system to be controlled, automated support can be provided for much of the safety analysis. We believe that by using a common model for both system and safety engineering and automating parts of the safety analysis, we can both reduce the cost and improve the quality of the safety analysis. Here we present our vision of model-based safety analysis and discuss the advantages and challenges in making this approach practical.
Lacson, Ronilda; O'Connor, Stacy D; Sahni, V Anik; Roy, Christopher; Dalal, Anuj; Desai, Sonali; Khorasani, Ramin
2016-07-01
Optimal critical test result communication is a Joint Commission national patient safety goal and requires documentation of closed-loop communication among care providers in the medical record. Electronic alert notification systems can facilitate an auditable process for creating alerts for transmission and acknowledgement of critical test results. We evaluated the impact of a patient safety initiative with an alert notification system on reducing critical results lacking documented communication, and assessed potential overuse of the alerting system for communicating results. We implemented an alert notification system-Alert Notification of Critical Results (ANCR)-in January 2010. We reviewed radiology reports finalised in 2009-2014 which lacked documented communication between the radiologist and another care provider, and assessed the impact of ANCR on the proportion of such reports with critical findings, using trend analysis over 10 semiannual time periods. To evaluate potential overuse of ANCR, we assessed the proportion of reports with non-critical results among provider-communicated reports. The proportion of reports with critical results among reports without documented communication decreased significantly over 4 years (2009-2014) from 0.19 to 0.05 (p<0.0001, Cochran-Armitage trend test). The proportion of provider-communicated reports with non-critical results remained unchanged over time before and after ANCR implementation (0.20 to 0.15, p=0.45, Cochran-Armitage trend test). A patient safety initiative with an alert notification system reduced the proportion of critical results among reports lacking documented communication between care providers. We observed no change in documented communication of non-critical results, suggesting the system did not promote overuse. Future studies are needed to evaluate whether such systems prevent subsequent patient harm. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
XtratuM: An Open Source Hypervisor for TSP Embedded Systems in Aerospace
NASA Astrophysics Data System (ADS)
Crespo, A.; Ripoll, I.; Masmano, M.; Arberet, P.; Metge, J. J.
2009-05-01
XtratuM is an hypervisor designed to meet safety critical requirements. XtratuM 2.1.0 is a redesign of the former version XtratuM 2.0 (for x86 architectures) to meet safety critical requirements. It has been ported to SPARC v8 arquitecture and specially to the to the LEON2 processor, which is the reference platform for the spatial sector. Adaptation involves a strong effort in redesign to be closer to the ARINC-653 standards. As far as we know, XtratuM is the first hypervisor for the SPARC v8 arquitecture. In this paper, the main design aspects are discussed and the internal architecture described. An initial evaluation of the most significant metrics is also provided.
A Comparison of Bus Architectures for Safety-Critical Embedded Systems
NASA Technical Reports Server (NTRS)
Rushby, John; Miner, Paul S. (Technical Monitor)
2003-01-01
We describe and compare the architectures of four fault-tolerant, safety-critical buses with a view to deducing principles common to all of them, the main differences in their design choices, and the tradeoffs made. Two of the buses come from an avionics heritage, and two from automobiles, though all four strive for similar levels of reliability and assurance. The avionics buses considered are the Honeywell SAFEbus (the backplane data bus used in the Boeing 777 Airplane Information Management System) and the NASA SPIDER (an architecture being developed as a demonstrator for certification under the new DO-254 guidelines); the automobile buses considered are the TTTech Time-Triggered Architecture (TTA), recently adopted by Audi for automobile applications, and by Honeywell for avionics and aircraft control functions, and FlexRay, which is being developed by a consortium of BMW, DaimlerChrysler, Motorola, and Philips.
People and computers--some recent highlights.
Shackel, B
2000-12-01
This paper aims to review selectively a fair proportion of the literature on human-computer interaction (HCI) over the three years since Shackel (J. Am. Soc. Inform. Sci. 48 (11) (1997) 970-986). After a brief note of history I discuss traditional input, output and workplace aspects, the web and 'E-topics', web-related aspects, virtual reality, safety-critical systems, and the need to move from HCI to human-system integration (HSI). Finally I suggest, and consider briefly, some future possibilities and issues including web consequences, embedded ubiquitous computing, and 'back to systems ergonomics?'.
``Carbon Credits'' for Resource-Bounded Computations Using Amortised Analysis
NASA Astrophysics Data System (ADS)
Jost, Steffen; Loidl, Hans-Wolfgang; Hammond, Kevin; Scaife, Norman; Hofmann, Martin
Bounding resource usage is important for a number of areas, notably real-time embedded systems and safety-critical systems. In this paper, we present a fully automatic static type-based analysis for inferring upper bounds on resource usage for programs involving general algebraic datatypes and full recursion. Our method can easily be used to bound any countable resource, without needing to revisit proofs. We apply the analysis to the important metrics of worst-case execution time, stack- and heap-space usage. Our results from several realistic embedded control applications demonstrate good matches between our inferred bounds and measured worst-case costs for heap and stack usage. For time usage we infer good bounds for one application. Where we obtain less tight bounds, this is due to the use of software floating-point libraries.
The VATES-Diamond as a Verifier's Best Friend
NASA Astrophysics Data System (ADS)
Glesner, Sabine; Bartels, Björn; Göthel, Thomas; Kleine, Moritz
Within a model-based software engineering process it needs to be ensured that properties of abstract specifications are preserved by transformations down to executable code. This is even more important in the area of safety-critical real-time systems where additionally non-functional properties are crucial. In the VATES project, we develop formal methods for the construction and verification of embedded systems. We follow a novel approach that allows us to formally relate abstract process algebraic specifications to their implementation in a compiler intermediate representation. The idea is to extract a low-level process algebraic description from the intermediate code and to formally relate it to previously developed abstract specifications. We apply this approach to a case study from the area of real-time operating systems and show that this approach has the potential to seamlessly integrate modeling, implementation, transformation and verification stages of embedded system development.
NASA Technical Reports Server (NTRS)
Goethel, Thomas; Glesner, Sabine
2009-01-01
The correctness of safety-critical embedded software is crucial, whereas non-functional properties like deadlock-freedom and real-time constraints are particularly important. The real-time calculus Timed Communicating Sequential Processes (CSP) is capable of expressing such properties and can therefore be used to verify embedded software. In this paper, we present our formalization of Timed CSP in the Isabelle/HOL theorem prover, which we have formulated as an operational coalgebraic semantics together with bisimulation equivalences and coalgebraic invariants. Furthermore, we apply these techniques in an abstract specification with real-time constraints, which is the basis for current work in which we verify the components of a simple real-time operating system deployed on a satellite.
NASA Astrophysics Data System (ADS)
Schoitsch, Erwin
1988-07-01
Our society is depending more and more on the reliability of embedded (real-time) computer systems even in every-day life. Considering the complexity of the real world, this might become a severe threat. Real-time programming is a discipline important not only in process control and data acquisition systems, but also in fields like communication, office automation, interactive databases, interactive graphics and operating systems development. General concepts of concurrent programming and constructs for process-synchronization are discussed in detail. Tasking and synchronization concepts, methods of process communication, interrupt- and timeout handling in systems based on semaphores, signals, conditional critical regions or on real-time languages like Concurrent PASCAL, MODULA, CHILL and ADA are explained and compared with each other and with respect to their potential to quality and safety.
Siegel, Nathan A; Kobayashi, Leo; Dunbar-Viveiros, Jennifer A; Devine, Jeffrey; Al-Rasheed, Rakan S; Gardiner, Fenwick G; Olsson, Krister; Lai, Stella; Jones, Mark S; Dannecker, Max; Overly, Frank L; Gosbee, John W; Portelli, David C; Jay, Gregory D
2015-06-01
Patient safety during emergency department procedural sedation (EDPS) can be difficult to study. Investigators sought to delineate and experimentally assess EDPS performance and safety practices of senior-level emergency medicine residents through in situ simulation. Study sessions used 2 pilot-tested EDPS scenarios with critical action checklists, institutional forms, embedded probes, and situational awareness questionnaires. An experimental informatics system was separately developed for bedside EDPS process guidance. Postgraduate year 3 and 4 subjects completed both scenarios in randomized order; only experimental subjects were provided with the experimental system during second scenarios. Twenty-four residents were recruited into a control group (n = 12; 6.2 ± 7.4 live EDPS experience) and experimental group (n = 12; 11.3 ± 8.2 live EDPS experience [P = 0.10]). Critical actions for EDPS medication selection, induction, and adverse event recognition with resuscitation were correctly performed by most subjects. Presedation evaluations, sedation rescue preparation, equipment checks, time-outs, and documentation were frequently missed. Time-outs and postsedation assessments increased during second scenarios in the experimental group. Emergency department procedural sedation safety probe detection did not change across scenarios in either group. Situational awareness scores were 51% ± 7% for control group and 58% ± 12% for experimental group. Subjects using the experimental system completed more time-outs and scored higher Simulation EDPS Safety Composite Scores, although without comprehensive improvements in EDPS practice or safety. Study simulations delineated EDPS and assessed safety behaviors in senior emergency medicine residents, who exhibited the requisite medical knowledge base and procedural skill set but lacked some nontechnical skills that pertain to emergency department microsystem functions and patient safety. The experimental system exhibited limited impact only on in-simulation time-out compliance.
Comments on the "Byzantine Self-Stabilizing Pulse Synchronization" Protocol: Counter-examples
NASA Technical Reports Server (NTRS)
Malekpour, Mahyar R.; Siminiceanu, Radu
2006-01-01
Embedded distributed systems have become an integral part of many safety-critical applications. There have been many attempts to solve the self-stabilization problem of clocks across a distributed system. An analysis of one such protocol called the Byzantine Self-Stabilizing Pulse Synchronization (BSS-Pulse-Synch) protocol from a paper entitled "Linear Time Byzantine Self-Stabilizing Clock Synchronization" by Daliot, et al., is presented in this report. This report also includes a discussion of the complexity and pitfalls of designing self-stabilizing protocols and provides counter-examples for the claims of the above protocol.
Automatic Implementation of Ttethernet-Based Time-Triggered Avionics Applications
NASA Astrophysics Data System (ADS)
Gorcitz, Raul Adrian; Carle, Thomas; Lesens, David; Monchaux, David; Potop-Butucaruy, Dumitru; Sorel, Yves
2015-09-01
The design of safety-critical embedded systems such as those used in avionics still involves largely manual phases. But in avionics the definition of standard interfaces embodied in standards such as ARINC 653 or TTEthernet should allow the definition of fully automatic code generation flows that reduce the costs while improving the quality of the generated code, much like compilers have done when replacing manual assembly coding. In this paper, we briefly present such a fully automatic implementation tool, called Lopht, for ARINC653-based time-triggered systems, and then explain how it is currently extended to include support for TTEthernet networks.
An Incremental Life-cycle Assurance Strategy for Critical System Certification
2014-11-04
for Safe Aircraft Operation Embedded software systems introduce a new class of problems not addressed by traditional system modeling & analysis...Platform Runtime Architecture Application Software Embedded SW System Engineer Data Stream Characteristics Latency jitter affects control behavior...do system level failures still occur despite fault tolerance techniques being deployed in systems ? Embedded software system as major source of
DOT National Transportation Integrated Search
2013-12-01
Monitoring installation of driven pile foundations : is critically important to ensure adequate safety : of structures with piles, such as the many bridges : which are maintained by the Florida Department : of Transportation (FDOT). Dynamic load test...
Systems thinking and incivility in nursing practice: An integrative review.
Phillips, Janet M; Stalter, Ann M; Winegardner, Sherri; Wiggs, Carol; Jauch, Amy
2018-01-23
There is a critical need for nurses and interprofessional healthcare providers to implement systems thinking (ST) across international borders, addressing incivility and its perilous effects on patient quality and safety. An estimated one million patients die in hospitals worldwide due to avoidable patient-related errors. Establishing safe and civil workplaces using ST is paramount to promoting clear, level-headed thinking from which patient-centered nursing actions can impact health systems. The purpose of the paper is to answer the research question, What ST evidence fosters the effect of workplace civility in practice settings? Whittemore and Knafl's integrative review method guided this study. The quality of articles was determined using Chu et al.'s Mixed Methods Assessment Tool. Thirty-eight studies were reviewed. Themes emerged describing antecedents and consequences of incivility as embedded within complex systems, suggesting improvements for civility and systems/ST in nursing practice. This integrative review provides information about worldwide incivility in nursing practice from a systems perspective. Several models are offered as a means of promoting civility in nursing practice to improve patient quality and safety. Further study is needed regarding incivility and resultant effects on patient quality and safety. © 2018 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Mbaya, Timmy
Embedded Aerospace Systems have to perform safety and mission critical operations in a real-time environment where timing and functional correctness are extremely important. Guidance, Navigation, and Control (GN&C) systems substantially rely on complex software interfacing with hardware in real-time; any faults in software or hardware, or their interaction could result in fatal consequences. Integrated Software Health Management (ISWHM) provides an approach for detection and diagnosis of software failures while the software is in operation. The ISWHM approach is based on probabilistic modeling of software and hardware sensors using a Bayesian network. To meet memory and timing constraints of real-time embedded execution, the Bayesian network is compiled into an Arithmetic Circuit, which is used for on-line monitoring. This type of system monitoring, using an ISWHM, provides automated reasoning capabilities that compute diagnoses in a timely manner when failures occur. This reasoning capability enables time-critical mitigating decisions and relieves the human agent from the time-consuming and arduous task of foraging through a multitude of isolated---and often contradictory---diagnosis data. For the purpose of demonstrating the relevance of ISWHM, modeling and reasoning is performed on a simple simulated aerospace system running on a real-time operating system emulator, the OSEK/Trampoline platform. Models for a small satellite and an F-16 fighter jet GN&C (Guidance, Navigation, and Control) system have been implemented. Analysis of the ISWHM is then performed by injecting faults and analyzing the ISWHM's diagnoses.
A system-level approach for embedded memory robustness
NASA Astrophysics Data System (ADS)
Mariani, Riccardo; Boschi, Gabriele
2005-11-01
New ultra-deep submicron technologies are bringing not only new advantages such extraordinary transistor densities or unforeseen performances, but also new uncertainties such soft-error susceptibility, modelling complexity, coupling effects, leakage contribution and increased sensitivity to internal and external disturbs. Nowadays, embedded memories are taking profit of such new technologies and they are more and more used in systems: therefore as robustness and reliability requirement increase, memory systems must be protected against different kind of faults (permanent and transient) and that should be done in an efficient way. It means that reliability and costs, such overhead and performance degradation, must be efficiently tuned based on the system and on the application. Moreover, the new emerging norms for safety-critical applications such IEC 61508 are requiring precise answers in terms of robustness also in the case of memory systems. In this paper, classical protection techniques for error detection and correction are enriched with a system-aware approach, where the memory system is analyzed based on its role in the application. A configurable memory protection system is presented, together with the results of its application to a proof-of-concept architecture. This work has been developed in the framework of MEDEA+ T126 project called BLUEBERRIES.
Yim, Taeeun; Park, Min-Sik; Woo, Sang-Gil; Kwon, Hyuk-Kwon; Yoo, Jung-Keun; Jung, Yeon Sik; Kim, Ki Jae; Yu, Ji-Sang; Kim, Young-Jun
2015-08-12
User safety is one of the most critical issues for the successful implementation of lithium ion batteries (LIBs) in electric vehicles and their further expansion in large-scale energy storage systems. Herein, we propose a novel approach to realize self-extinguishing capability of LIBs for effective safety improvement by integrating temperature-responsive microcapsules containing a fire-extinguishing agent. The microcapsules are designed to release an extinguisher agent upon increased internal temperature of an LIB, resulting in rapid heat absorption through an in situ endothermic reaction and suppression of further temperature rise and undesirable thermal runaway. In a standard nail penetration test, the temperature rise is reduced by 74% without compromising electrochemical performances. It is anticipated that on the strengths of excellent scalability, simplicity, and cost-effectiveness, this novel strategy can be extensively applied to various high energy-density devices to ensure human safety.
Healthcare software assurance.
Cooper, Jason G; Pauley, Keith A
2006-01-01
Software assurance is a rigorous, lifecycle phase-independent set of activities which ensure completeness, safety, and reliability of software processes and products. This is accomplished by guaranteeing conformance to all requirements, standards, procedures, and regulations. These assurance processes are even more important when coupled with healthcare software systems, embedded software in medical instrumentation, and other healthcare-oriented life-critical systems. The current Food and Drug Administration (FDA) regulatory requirements and guidance documentation do not address certain aspects of complete software assurance activities. In addition, the FDA's software oversight processes require enhancement to include increasingly complex healthcare systems such as Hospital Information Systems (HIS). The importance of complete software assurance is introduced, current regulatory requirements and guidance discussed, and the necessity for enhancements to the current processes shall be highlighted.
Cooper, Jason G.; Pauley, Keith A.
2006-01-01
Software assurance is a rigorous, lifecycle phase-independent set of activities which ensure completeness, safety, and reliability of software processes and products. This is accomplished by guaranteeing conformance to all requirements, standards, procedures, and regulations. These assurance processes are even more important when coupled with healthcare software systems, embedded software in medical instrumentation, and other healthcare-oriented life-critical systems. The current Food and Drug Administration (FDA) regulatory requirements and guidance documentation do not address certain aspects of complete software assurance activities. In addition, the FDA’s software oversight processes require enhancement to include increasingly complex healthcare systems such as Hospital Information Systems (HIS). The importance of complete software assurance is introduced, current regulatory requirements and guidance discussed, and the necessity for enhancements to the current processes shall be highlighted. PMID:17238324
Lowry, Svetlana Z; Patterson, Emily S
2014-01-01
Background There is growing recognition that design flaws in health information technology (HIT) lead to increased cognitive work, impact workflows, and produce other undesirable user experiences that contribute to usability issues and, in some cases, patient harm. These usability issues may in turn contribute to HIT utilization disparities and patient safety concerns, particularly among “non-typical” HIT users and their health care providers. Health care disparities are associated with poor health outcomes, premature death, and increased health care costs. HIT has the potential to reduce these disparate outcomes. In the computer science field, it has long been recognized that embedded cultural assumptions can reduce the usability, usefulness, and safety of HIT systems for populations whose characteristics differ from “stereotypical” users. Among these non-typical users, inappropriate embedded design assumptions may contribute to health care disparities. It is unclear how to address potentially inappropriate embedded HIT design assumptions once detected. Objective The objective of this paper is to explain HIT universal design principles derived from the human factors engineering literature that can help to overcome potential usability and/or patient safety issues that are associated with unrecognized, embedded assumptions about cultural groups when designing HIT systems. Methods Existing best practices, guidance, and standards in software usability and accessibility were subjected to a 5-step expert review process to identify and summarize those best practices, guidance, and standards that could help identify and/or address embedded design assumptions in HIT that could negatively impact patient safety, particularly for non-majority HIT user populations. An iterative consensus-based process was then used to derive evidence-based design principles from the data to address potentially inappropriate embedded cultural assumptions. Results Design principles that may help identify and address embedded HIT design assumptions are available in the existing literature. Conclusions Evidence-based HIT design principles derived from existing human factors and informatics literature can help HIT developers identify and address embedded cultural assumptions that may underlie HIT-associated usability and patient safety concerns as well as health care disparities. PMID:27025349
Gibbons, Michael C; Lowry, Svetlana Z; Patterson, Emily S
2014-12-18
There is growing recognition that design flaws in health information technology (HIT) lead to increased cognitive work, impact workflows, and produce other undesirable user experiences that contribute to usability issues and, in some cases, patient harm. These usability issues may in turn contribute to HIT utilization disparities and patient safety concerns, particularly among "non-typical" HIT users and their health care providers. Health care disparities are associated with poor health outcomes, premature death, and increased health care costs. HIT has the potential to reduce these disparate outcomes. In the computer science field, it has long been recognized that embedded cultural assumptions can reduce the usability, usefulness, and safety of HIT systems for populations whose characteristics differ from "stereotypical" users. Among these non-typical users, inappropriate embedded design assumptions may contribute to health care disparities. It is unclear how to address potentially inappropriate embedded HIT design assumptions once detected. The objective of this paper is to explain HIT universal design principles derived from the human factors engineering literature that can help to overcome potential usability and/or patient safety issues that are associated with unrecognized, embedded assumptions about cultural groups when designing HIT systems. Existing best practices, guidance, and standards in software usability and accessibility were subjected to a 5-step expert review process to identify and summarize those best practices, guidance, and standards that could help identify and/or address embedded design assumptions in HIT that could negatively impact patient safety, particularly for non-majority HIT user populations. An iterative consensus-based process was then used to derive evidence-based design principles from the data to address potentially inappropriate embedded cultural assumptions. Design principles that may help identify and address embedded HIT design assumptions are available in the existing literature. Evidence-based HIT design principles derived from existing human factors and informatics literature can help HIT developers identify and address embedded cultural assumptions that may underlie HIT-associated usability and patient safety concerns as well as health care disparities.
Beacon system based on light-emitting diode sources for runways lighting
NASA Astrophysics Data System (ADS)
Montes, Mario González; Vázquez, Daniel; Fernandez-Balbuena, Antonio A.; Bernabeu, Eusebio
2014-06-01
New aeronautical ground lighting techniques are becoming increasingly important to ensure the safety and reduce the maintenance costs of the plane's tracks. Until recently, tracks had embedded lighting systems whose sources were based on incandescent lamps. But incandescent lamps have several disadvantages: high energy consumption and frequent breakdowns that result in high maintenance costs (lamp average life-time is ˜1500 operating hours) and the lamp's technology has a lack of new lighting functions, such as signal handling and modification. To solve these problems, the industry has developed systems based on light-emitting diode (LED) technology with improved features: (1) LED lighting consumes one tenth the power, (2) it improves preventive maintenance (an LED's lifetime range is between 25,000 and 100,000 hours), and (3) LED lighting technology can be controlled remotely according to the needs of the track configuration. LEDs have been in use for more than three decades, but only recently, around 2002, have they begun to be used as visual aids, representing the greatest potential change for airport lighting since their inception in the 1920s. Currently, embedded LED systems are not being broadly used due to the specific constraints of the rules and regulations of airports (beacon dimensions, power system technology, etc.). The fundamental requirements applied to embedded lighting systems are to be hosted on a volume where the dimensions are usually critical and also to integrate all the essential components for operation. An embedded architecture that meets the lighting regulations for airport runways is presented. The present work is divided into three main tasks: development of an optical system to optimize lighting according to International Civil Aviation Organization, manufacturing prototype, and model validation.
Localized attacks on spatially embedded networks with dependencies.
Berezin, Yehiel; Bashan, Amir; Danziger, Michael M; Li, Daqing; Havlin, Shlomo
2015-03-11
Many real world complex systems such as critical infrastructure networks are embedded in space and their components may depend on one another to function. They are also susceptible to geographically localized damage caused by malicious attacks or natural disasters. Here, we study a general model of spatially embedded networks with dependencies under localized attacks. We develop a theoretical and numerical approach to describe and predict the effects of localized attacks on spatially embedded systems with dependencies. Surprisingly, we find that a localized attack can cause substantially more damage than an equivalent random attack. Furthermore, we find that for a broad range of parameters, systems which appear stable are in fact metastable. Though robust to random failures-even of finite fraction-if subjected to a localized attack larger than a critical size which is independent of the system size (i.e., a zero fraction), a cascading failure emerges which leads to complete system collapse. Our results demonstrate the potential high risk of localized attacks on spatially embedded network systems with dependencies and may be useful for designing more resilient systems.
Advanced information processing system: Authentication protocols for network communication
NASA Technical Reports Server (NTRS)
Harper, Richard E.; Adams, Stuart J.; Babikyan, Carol A.; Butler, Bryan P.; Clark, Anne L.; Lala, Jaynarayan H.
1994-01-01
In safety critical I/O and intercomputer communication networks, reliable message transmission is an important concern. Difficulties of communication and fault identification in networks arise primarily because the sender of a transmission cannot be identified with certainty, an intermediate node can corrupt a message without certainty of detection, and a babbling node cannot be identified and silenced without lengthy diagnosis and reconfiguration . Authentication protocols use digital signature techniques to verify the authenticity of messages with high probability. Such protocols appear to provide an efficient solution to many of these problems. The objective of this program is to develop, demonstrate, and evaluate intercomputer communication architectures which employ authentication. As a context for the evaluation, the authentication protocol-based communication concept was demonstrated under this program by hosting a real-time flight critical guidance, navigation and control algorithm on a distributed, heterogeneous, mixed redundancy system of workstations and embedded fault-tolerant computers.
Mission-Oriented Sensor Arrays and UAVs - a Case Study on Environmental Monitoring
NASA Astrophysics Data System (ADS)
Figueira, N. M.; Freire, I. L.; Trindade, O.; Simões, E.
2015-08-01
This paper presents a new concept of UAV mission design in geomatics, applied to the generation of thematic maps for a multitude of civilian and military applications. We discuss the architecture of Mission-Oriented Sensors Arrays (MOSA), proposed in Figueira et Al. (2013), aimed at splitting and decoupling the mission-oriented part of the system (non safety-critical hardware and software) from the aircraft control systems (safety-critical). As a case study, we present an environmental monitoring application for the automatic generation of thematic maps to track gunshot activity in conservation areas. The MOSA modeled for this application integrates information from a thermal camera and an on-the-ground microphone array. The use of microphone arrays technology is of particular interest in this paper. These arrays allow estimation of the direction-of-arrival (DOA) of the incoming sound waves. Information about events of interest is obtained by the fusion of the data provided by the microphone array, captured by the UAV, fused with information from the termal image processing. Preliminary results show the feasibility of the on-the-ground sound processing array and the simulation of the main processing module, to be embedded into an UAV in a future work. The main contributions of this paper are the proposed MOSA system, including concepts, models and architecture.
An Approach to V&V of Embedded Adaptive Systems
NASA Technical Reports Server (NTRS)
Liu, Yan; Yerramalla, Sampath; Fuller, Edgar; Cukic, Bojan; Gururajan, Srikaruth
2004-01-01
Rigorous Verification and Validation (V&V) techniques are essential for high assurance systems. Lately, the performance of some of these systems is enhanced by embedded adaptive components in order to cope with environmental changes. Although the ability of adapting is appealing, it actually poses a problem in terms of V&V. Since uncertainties induced by environmental changes have a significant impact on system behavior, the applicability of conventional V&V techniques is limited. In safety-critical applications such as flight control system, the mechanisms of change must be observed, diagnosed, accommodated and well understood prior to deployment. In this paper, we propose a non-conventional V&V approach suitable for online adaptive systems. We apply our approach to an intelligent flight control system that employs a particular type of Neural Networks (NN) as the adaptive learning paradigm. Presented methodology consists of a novelty detection technique and online stability monitoring tools. The novelty detection technique is based on Support Vector Data Description that detects novel (abnormal) data patterns. The Online Stability Monitoring tools based on Lyapunov's Stability Theory detect unstable learning behavior in neural networks. Cases studies based on a high fidelity simulator of NASA's Intelligent Flight Control System demonstrate a successful application of the presented V&V methodology. ,
ESSAA: Embedded system safety analysis assistant
NASA Technical Reports Server (NTRS)
Wallace, Peter; Holzer, Joseph; Guarro, Sergio; Hyatt, Larry
1987-01-01
The Embedded System Safety Analysis Assistant (ESSAA) is a knowledge-based tool that can assist in identifying disaster scenarios. Imbedded software issues hazardous control commands to the surrounding hardware. ESSAA is intended to work from outputs to inputs, as a complement to simulation and verification methods. Rather than treating the software in isolation, it examines the context in which the software is to be deployed. Given a specified disasterous outcome, ESSAA works from a qualitative, abstract model of the complete system to infer sets of environmental conditions and/or failures that could cause a disasterous outcome. The scenarios can then be examined in depth for plausibility using existing techniques.
Palo Alto Research Center - Smart Embedded Network of Sensors with an Optical Readout
Raghavan, Ajay; Sahu, Saroj; Bringans, Ross; Johnson, Noble; Kiesel, Peter; Saha, Bhaskar
2018-05-18
PARC is developing new fiber optic sensors that would be embedded into batteries to monitor and measure key internal parameters during charge and discharge cycles. Two significant problems with today's best batteries are their lack of internal monitoring capabilities and their design oversizing. The lack of monitoring interferes with the ability to identify and manage performance or safety issues as they arise, which are presently managed by very conservative design oversizing and protection approaches that result in cost inefficiencies. PARC's design combines low-cost, embedded optical battery sensors and smart algorithms to overcome challenges faced by today's best battery management systems. These advanced fiber optic sensing technologies have the potential to dramatically improve the safety, performance, and life-time of energy storage systems.
A Course in Real-Time Embedded Software
ERIC Educational Resources Information Center
Archibald, J. K.; Fife, W. S.
2007-01-01
Embedded systems are increasingly pervasive, and the creation of reliable controlling software offers unique challenges. Embedded software must interact directly with hardware, it must respond to events in a time-critical fashion, and it typically employs concurrency to meet response time requirements. This paper describes an innovative course…
Self-Test Procedures for Gas Sensors Embedded in Microreactor Systems
Helwig, Andreas; Hackner, Angelika; Zappa, Dario; Sberveglieri, Giorgio
2018-01-01
Metal oxide (MOX) gas sensors sensitively respond to a wide variety of combustible, explosive and poisonous gases. However, due to the lack of a built-in self-test capability, MOX gas sensors have not yet been able to penetrate safety-critical applications. In the present work we report on gas sensing experiments performed on MOX gas sensors embedded in ceramic micro-reaction chambers. With the help of an external micro-pump, such systems can be operated in a periodic manner alternating between flow and no-flow conditions, thus allowing repetitive measurements of the sensor resistances under clean air, R0, and under gas exposure, Rgas, to be obtained, even under field conditions. With these pairs of resistance values, eventual drifts in the sensor baseline resistance can be detected and drift-corrected values of the relative resistance response Resp=(R0−Rgas)/R0 can be determined. Residual poisoning-induced changes in the relative resistance response can be detected by reference to humidity measurements taken with room-temperature-operated capacitive humidity sensors which are insensitive to the poisoning processes operative on heated MOX gas sensors. PMID:29401673
Safety Capital: The Management of Organizational Knowledge on Occupational Health and Safety
ERIC Educational Resources Information Center
Nunez, Imanol; Villanueva, Mikel
2011-01-01
Purpose: The concept of Safety Capital was developed by analyzing the creation and composition of the Intellectual Capital embedded in Occupational Health and Safety (OHS) systems. The paper aims to address this relationship. Design/methodology/approach: By drawing a theoretical link for the relationship between OHS activities and intellectual…
A Review on Internet of Things for Defense and Public Safety
Fraga-Lamas, Paula; Fernández-Caramés, Tiago M.; Suárez-Albela, Manuel; Castedo, Luis; González-López, Miguel
2016-01-01
The Internet of Things (IoT) is undeniably transforming the way that organizations communicate and organize everyday businesses and industrial procedures. Its adoption has proven well suited for sectors that manage a large number of assets and coordinate complex and distributed processes. This survey analyzes the great potential for applying IoT technologies (i.e., data-driven applications or embedded automation and intelligent adaptive systems) to revolutionize modern warfare and provide benefits similar to those in industry. It identifies scenarios where Defense and Public Safety (PS) could leverage better commercial IoT capabilities to deliver greater survivability to the warfighter or first responders, while reducing costs and increasing operation efficiency and effectiveness. This article reviews the main tactical requirements and the architecture, examining gaps and shortcomings in existing IoT systems across the military field and mission-critical scenarios. The review characterizes the open challenges for a broad deployment and presents a research roadmap for enabling an affordable IoT for defense and PS. PMID:27782052
A Review on Internet of Things for Defense and Public Safety.
Fraga-Lamas, Paula; Fernández-Caramés, Tiago M; Suárez-Albela, Manuel; Castedo, Luis; González-López, Miguel
2016-10-05
The Internet of Things (IoT) is undeniably transforming the way that organizations communicate and organize everyday businesses and industrial procedures. Its adoption has proven well suited for sectors that manage a large number of assets and coordinate complex and distributed processes. This survey analyzes the great potential for applying IoT technologies (i.e., data-driven applications or embedded automation and intelligent adaptive systems) to revolutionize modern warfare and provide benefits similar to those in industry. It identifies scenarios where Defense and Public Safety (PS) could leverage better commercial IoT capabilities to deliver greater survivability to the warfighter or first responders, while reducing costs and increasing operation efficiency and effectiveness. This article reviews the main tactical requirements and the architecture, examining gaps and shortcomings in existing IoT systems across the military field and mission-critical scenarios. The review characterizes the open challenges for a broad deployment and presents a research roadmap for enabling an affordable IoT for defense and PS.
Kobayashi, Leo; Boss, Robert M; Gibbs, Frantz J; Goldlust, Eric; Hennedy, Michelle M; Monti, James E; Siegel, Nathan A
2011-01-01
Investigators studied an emergency department (ED) physical chart system and identified inconsistent, small font labeling; a single-color scheme; and an absence of human factors engineering (HFE) cues. A case study and description of the methodology with which surrogate measures of chart-related patient safety were studied and subsequently used to reduce latent hazards are presented. Medical records present a challenge to patient safety in EDs. Application of HFE can improve specific aspects of existing medical chart organization systems as they pertain to patient safety in acute care environments. During 10 random audits over 5 consecutive days (573 data points), 56 (9.8%) chart binders (range 0.0-23%) were found to be either misplaced or improperly positioned relative to other chart binders; 12 (21%) were in the critical care area. HFE principles were applied to develop an experimental chart binder system with alternating color-based chart groupings, simple and prominent identifiers, and embedded visual cues. Post-intervention audits revealed significant reductions in chart binder location problems overall (p < 0.01), for Urgent Care A and B pods (6.4% to 1.2%; p < 0.05), Fast Track C pod (19.3% to 0.0%; p < 0.05) and Behavioral/Substance Abuse D pod (15.7% to 0.0%; p < 0.05) areas of the ED. The critical care room area did not display an improvement (11.4% to 13.2%; p = 0.40). Application of HFE methods may aid the development, assessment, and modification of acute care clinical environments through evidence-based design methodologies and contribute to safe patient care delivery.
Software Safety Risk in Legacy Safety-Critical Computer Systems
NASA Technical Reports Server (NTRS)
Hill, Janice; Baggs, Rhoda
2007-01-01
Safety-critical computer systems must be engineered to meet system and software safety requirements. For legacy safety-critical computer systems, software safety requirements may not have been formally specified during development. When process-oriented software safety requirements are levied on a legacy system after the fact, where software development artifacts don't exist or are incomplete, the question becomes 'how can this be done?' The risks associated with only meeting certain software safety requirements in a legacy safety-critical computer system must be addressed should such systems be selected as candidates for reuse. This paper proposes a method for ascertaining formally, a software safety risk assessment, that provides measurements for software safety for legacy systems which may or may not have a suite of software engineering documentation that is now normally required. It relies upon the NASA Software Safety Standard, risk assessment methods based upon the Taxonomy-Based Questionnaire, and the application of reverse engineering CASE tools to produce original design documents for legacy systems.
Real-Time System Verification by Kappa-Induction
NASA Technical Reports Server (NTRS)
Pike, Lee S.
2005-01-01
We report the first formal verification of a reintegration protocol for a safety-critical, fault-tolerant, real-time distributed embedded system. A reintegration protocol increases system survivability by allowing a node that has suffered a fault to regain state consistent with the operational nodes. The protocol is verified in the Symbolic Analysis Laboratory (SAL), where bounded model checking and decision procedures are used to verify infinite-state systems by k-induction. The protocol and its environment are modeled as synchronizing timeout automata. Because k-induction is exponential with respect to k, we optimize the formal model to reduce the size of k. Also, the reintegrator's event-triggered behavior is conservatively modeled as time-triggered behavior to further reduce the size of k and to make it invariant to the number of nodes modeled. A corollary is that a clique avoidance property is satisfied.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, T.
2000-07-01
The Write One, Run Many (WORM) site (worm.csirc.net) is the on-line home of the WORM language and is hosted by the Criticality Safety Information Resource Center (CSIRC) (www.csirc.net). The purpose of this web site is to create an on-line community for WORM users to gather, share, and archive WORM-related information. WORM is an embedded, functional, programming language designed to facilitate the creation of input decks for computer codes that take standard ASCII text files as input. A functional programming language is one that emphasizes the evaluation of expressions, rather than execution of commands. The simplest and perhaps most common examplemore » of a functional language is a spreadsheet such as Microsoft Excel. The spreadsheet user specifies expressions to be evaluated, while the spreadsheet itself determines the commands to execute, as well as the order of execution/evaluation. WORM functions in a similar fashion and, as a result, is very simple to use and easy to learn. WORM improves the efficiency of today's criticality safety analyst by allowing: (1) input decks for parameter studies to be created quickly and easily; (2) calculations and variables to be embedded into any input deck, thus allowing for meaningful parameter specifications; (3) problems to be specified using any combination of units; and (4) complex mathematically defined models to be created. WORM is completely written in Perl. Running on all variants of UNIX, Windows, MS-DOS, MacOS, and many other operating systems, Perl is one of the most portable programming languages available. As such, WORM works on practically any computer platform.« less
Speculation detection for Chinese clinical notes: Impacts of word segmentation and embedding models.
Zhang, Shaodian; Kang, Tian; Zhang, Xingting; Wen, Dong; Elhadad, Noémie; Lei, Jianbo
2016-04-01
Speculations represent uncertainty toward certain facts. In clinical texts, identifying speculations is a critical step of natural language processing (NLP). While it is a nontrivial task in many languages, detecting speculations in Chinese clinical notes can be particularly challenging because word segmentation may be necessary as an upstream operation. The objective of this paper is to construct a state-of-the-art speculation detection system for Chinese clinical notes and to investigate whether embedding features and word segmentations are worth exploiting toward this overall task. We propose a sequence labeling based system for speculation detection, which relies on features from bag of characters, bag of words, character embedding, and word embedding. We experiment on a novel dataset of 36,828 clinical notes with 5103 gold-standard speculation annotations on 2000 notes, and compare the systems in which word embeddings are calculated based on word segmentations given by general and by domain specific segmenters respectively. Our systems are able to reach performance as high as 92.2% measured by F score. We demonstrate that word segmentation is critical to produce high quality word embedding to facilitate downstream information extraction applications, and suggest that a domain dependent word segmenter can be vital to such a clinical NLP task in Chinese language. Copyright © 2016 Elsevier Inc. All rights reserved.
Traceability of Software Safety Requirements in Legacy Safety Critical Systems
NASA Technical Reports Server (NTRS)
Hill, Janice L.
2007-01-01
How can traceability of software safety requirements be created for legacy safety critical systems? Requirements in safety standards are imposed most times during contract negotiations. On the other hand, there are instances where safety standards are levied on legacy safety critical systems, some of which may be considered for reuse for new applications. Safety standards often specify that software development documentation include process-oriented and technical safety requirements, and also require that system and software safety analyses are performed supporting technical safety requirements implementation. So what can be done if the requisite documents for establishing and maintaining safety requirements traceability are not available?
NASA Astrophysics Data System (ADS)
Robinson, Nidia; Saafi, Mohamed
2006-03-01
Critical civil infrastructure systems such as bridges, high rises, dams, nuclear power plants and pipelines present a major investment and the health of the United States' economy and the lifestyle of its citizens both depend on their safety and security. The challenge for engineers is to maintain the safety and security of these large structures in the face of terrorism threats, natural disasters and long-term deterioration, as well as to meet the demands of emergency response times. With the significant negative impact that these threats can have on the structural environment, health monitoring of civil infrastructure holds promise as a way to provide information for near real-time condition assessment of the structure's safety and security. This information can be used to assess the integrity of the structure for post-earthquake and terrorist attacks rescue and recovery, and to safely and rapidly remove the debris and to temporary shore specific structural elements. This information can also be used for identification of incipient damage in structures experiencing long-term deterioration. However, one of the major obstacles preventing sensor-based monitoring is the lack of reliable, easy-to-install, cost-effective and harsh environment resistant sensors that can be densely embedded into large-scale civil infrastructure systems. Nanotechnology and MEMS-based systems which have matured in recent years represent an innovative solution to current damage detection systems, leading to wireless, inexpensive, durable, compact, and high-density information collection. In this paper, ongoing research activities at Alabama A&M University (AAMU) Center for Transportation Infrastructure Safety and Security on the application of nanotechnology and MEMS to Civil Infrastructure for health monitoring will presented. To date, research showed that nanotechnology and MEMS-based systems can be used to wirelessly detect and monitor different damage mechanisms in concrete structures as well as monitor critical structures' stability during floods and barge impact. However, some technical issues that needs to be addressed before full implementation of these new systems and will also be discussed in this paper.
Conformal and embedded IDT microsensors for health monitoring of structures
NASA Astrophysics Data System (ADS)
Varadan, Vijay K.; Varadan, Vasundara V.
2000-06-01
MEMS are currently being applied to the structural health monitoring of critical aircraft components and composites. The approach integrates acoustic emission, strain gauges, MEMS accelerometers and vibration monitoring aircraft components with a known history of catastrophic failure due to fracture. Recently a combination of the need for safety in the air and the desire to control costs is encouraging the use of in-flight monitoring of aircraft components and systems using light-weight, wireless and cost effective microsensors and MEMS. An in-situ aircraft structural health monitoring system, with sensors embedded in the composite structure or surface-mounted on the structure, would permit the timely detection of damage in aircraft. Micromachining offers the potential for fabricating a range of microsensor and MEMS for structural applications including load, vibration and acoustics characterization and monitoring. Such microsensors are extremely small; they can be embedded into structural materials, can be mass-produced and are therefore potentially cheap. The smart sensors are being developed using the standard microelectronics and micromachining in conjunction with novel Penn State wireless communication systems suitable for condition monitoring of aircraft structures in-flight. The main application areas of this investigation include continuos monitoring of a) structural integrity of aging aircraft, b) fatigue cracking, c) corrosion, d) deflection and strain of aircraft structures, wings, and rotorblades, e) impact damage, f) delamination and g) location and propagation of cracks. In this paper we give an overview of wireless programmable microsensors and MEMS and their associated driving electronics for such applications.
A design and implementation methodology for diagnostic systems
NASA Technical Reports Server (NTRS)
Williams, Linda J. F.
1988-01-01
A methodology for design and implementation of diagnostic systems is presented. Also discussed are the advantages of embedding a diagnostic system in a host system environment. The methodology utilizes an architecture for diagnostic system development that is hierarchical and makes use of object-oriented representation techniques. Additionally, qualitative models are used to describe the host system components and their behavior. The methodology architecture includes a diagnostic engine that utilizes a combination of heuristic knowledge to control the sequence of diagnostic reasoning. The methodology provides an integrated approach to development of diagnostic system requirements that is more rigorous than standard systems engineering techniques. The advantages of using this methodology during various life cycle phases of the host systems (e.g., National Aerospace Plane (NASP)) include: the capability to analyze diagnostic instrumentation requirements during the host system design phase, a ready software architecture for implementation of diagnostics in the host system, and the opportunity to analyze instrumentation for failure coverage in safety critical host system operations.
ERIC Educational Resources Information Center
Pollack, Julia
2017-01-01
This project considers the efficacy and scalability of embedded librarianship initiatives within the City University of New York (CUNY) library system and presents findings of an original research study conducted in 2015. Through an analysis of recent LIS literature on embedment, response data from a survey of librarians, and a selection of…
Self-Test Procedures for Gas Sensors Embedded in Microreactor Systems.
Helwig, Andreas; Hackner, Angelika; Müller, Gerhard; Zappa, Dario; Sberveglieri, Giorgio
2018-02-03
Metal oxide (MOX) gas sensors sensitively respond to a wide variety of combustible, explosive and poisonous gases. However, due to the lack of a built-in self-test capability, MOX gas sensors have not yet been able to penetrate safety-critical applications. In the present work we report on gas sensing experiments performed on MOX gas sensors embedded in ceramic micro-reaction chambers. With the help of an external micro-pump, such systems can be operated in a periodic manner alternating between flow and no-flow conditions, thus allowing repetitive measurements of the sensor resistances under clean air, R 0 , and under gas exposure, R g a s , to be obtained, even under field conditions. With these pairs of resistance values, eventual drifts in the sensor baseline resistance can be detected and drift-corrected values of the relative resistance response R e s p = ( R 0 - R g a s ) / R 0 can be determined. Residual poisoning-induced changes in the relative resistance response can be detected by reference to humidity measurements taken with room-temperature-operated capacitive humidity sensors which are insensitive to the poisoning processes operative on heated MOX gas sensors.
Closing the Gap: Cybersecurity for U.S. Forces and Commands
2017-03-30
Dickson, Ph.D. Professor of Military Studies , JAWS Thesis Advisor Kevin Therrien, Col, USAF Committee Member Stephen Rogers, Colonel, USA Director...infrastructures, and includes the Internet, telecommunications networks, computer systems, and embedded processors and controllers in critical industries.”5...of information technology infrastructures, including the Internet, telecommunications networks, computer systems, and embedded processors and
[What Surgeons Should Know about Risk Management].
Strametz, R; Tannheimer, M; Rall, M
2017-02-01
Background: The fact that medical treatment is associated with errors has long been recognized. Based on the principle of "first do no harm", numerous efforts have since been made to prevent such errors or limit their impact. However, recent statistics show that these measures do not sufficiently prevent grave mistakes with serious consequences. Preventable mistakes such as wrong patient or wrong site surgery still frequently occur in error statistics. Methods: Based on insight from research on human error, in due consideration of recent legislative regulations in Germany, the authors give an overview of the clinical risk management tools needed to identify risks in surgery, analyse their causes, and determine adequate measures to manage those risks depending on their relevance. The use and limitations of critical incident reporting systems (CIRS), safety checklists and crisis resource management (CRM) are highlighted. Also the rationale for IT systems to support the risk management process is addressed. Results/Conclusion: No single tool of risk management can be effective as a standalone instrument, but unfolds its effect only when embedded in a superordinate risk management system, which integrates tailor-made elements to increase patient safety into the workflows of each organisation. Competence in choosing adequate tools, effective IT systems to support the risk management process as well as leadership and commitment to constructive handling of human error are crucial components to establish a safety culture in surgery. Georg Thieme Verlag KG Stuttgart · New York.
48 CFR 209.270 - Aviation and ship critical safety items.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Aviation and ship critical safety items. 209.270 Section 209.270 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements 209.270 Aviation and ship critical safety items. ...
48 CFR 209.270 - Aviation and ship critical safety items.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Aviation and ship critical safety items. 209.270 Section 209.270 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements 209.270 Aviation and ship critical safety items. ...
48 CFR 209.270 - Aviation and ship critical safety items.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Aviation and ship critical safety items. 209.270 Section 209.270 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements 209.270 Aviation and ship critical safety items. ...
48 CFR 209.270 - Aviation and ship critical safety items.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Aviation and ship critical safety items. 209.270 Section 209.270 Federal Acquisition Regulations System DEFENSE ACQUISITION... Requirements 209.270 Aviation and ship critical safety items. ...
48 CFR 209.270 - Aviation and ship critical safety items.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Requirements 209.270 Aviation and ship critical safety items. ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Aviation and ship critical safety items. 209.270 Section 209.270 Federal Acquisition Regulations System DEFENSE ACQUISITION...
NASA Astrophysics Data System (ADS)
Song, Young-Gi; Seol, Kyung-Tae; Jang, Ji-Ho; Kwon, Hyeok-Jung; Cho, Yong-Sub
2012-07-01
The Proton Engineering Frontier Project (PEFP) 20-MeV proton linear accelerator is currently operating at the Korea Atomic Energy Research Institute (KAERI). The ion source of the 100-MeV proton linac needs at least a 100-hour operation time. To meet the goal, we have developed a microwave ion source that uses no filament. For the ion source, a remote control system has been developed by using experimental physics and the industrial control system (EPICS) software framework. The control system consists of a versa module europa (VME) and EPICS-based embedded applications running on a VxWorks real-time operating system. The main purpose of the control system is to control and monitor the operational variables of the components remotely and to protect operators from radiation exposure and the components from critical problems during beam extraction. We successfully performed the operation test of the control system to confirm the degree of safety during the hardware performance.
Semantic Annotation of Complex Text Structures in Problem Reports
NASA Technical Reports Server (NTRS)
Malin, Jane T.; Throop, David R.; Fleming, Land D.
2011-01-01
Text analysis is important for effective information retrieval from databases where the critical information is embedded in text fields. Aerospace safety depends on effective retrieval of relevant and related problem reports for the purpose of trend analysis. The complex text syntax in problem descriptions has limited statistical text mining of problem reports. The presentation describes an intelligent tagging approach that applies syntactic and then semantic analysis to overcome this problem. The tags identify types of problems and equipment that are embedded in the text descriptions. The power of these tags is illustrated in a faceted searching and browsing interface for problem report trending that combines automatically generated tags with database code fields and temporal information.
Overview of Risk Mitigation for Safety-Critical Computer-Based Systems
NASA Technical Reports Server (NTRS)
Torres-Pomales, Wilfredo
2015-01-01
This report presents a high-level overview of a general strategy to mitigate the risks from threats to safety-critical computer-based systems. In this context, a safety threat is a process or phenomenon that can cause operational safety hazards in the form of computational system failures. This report is intended to provide insight into the safety-risk mitigation problem and the characteristics of potential solutions. The limitations of the general risk mitigation strategy are discussed and some options to overcome these limitations are provided. This work is part of an ongoing effort to enable well-founded assurance of safety-related properties of complex safety-critical computer-based aircraft systems by developing an effective capability to model and reason about the safety implications of system requirements and design.
Embedded real-time operating system micro kernel design
NASA Astrophysics Data System (ADS)
Cheng, Xiao-hui; Li, Ming-qiang; Wang, Xin-zheng
2005-12-01
Embedded systems usually require a real-time character. Base on an 8051 microcontroller, an embedded real-time operating system micro kernel is proposed consisting of six parts, including a critical section process, task scheduling, interruption handle, semaphore and message mailbox communication, clock managent and memory managent. Distributed CPU and other resources are among tasks rationally according to the importance and urgency. The design proposed here provides the position, definition, function and principle of micro kernel. The kernel runs on the platform of an ATMEL AT89C51 microcontroller. Simulation results prove that the designed micro kernel is stable and reliable and has quick response while operating in an application system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DAVIS, S.J.
2000-05-25
This document identifies critical characteristics of components to be dedicated for use in Safety Class (SC) or Safety Significant (SS) Systems, Structures, or Components (SSCs). This document identifies the requirements for the components of the common radiation area monitor alarm in the WESF pool cell. These are procured as Commercial Grade Items (CGI), with the qualification testing and formal dedication to be performed at the Waste Encapsulation Storage Facility (WESF), in safety class, safety significant systems. System modifications are to be performed in accordance with the instructions provided on ECN 658230. Components for this change are commercially available and interchangeablemore » with the existing alarm configuration This document focuses on the operational requirements for alarm, declaration of the safety classification, identification of critical characteristics, and interpretation of requirements for procurement. Critical characteristics are identified herein and must be verified, followed by formal dedication, prior to the components being used in safety related applications.« less
Fuzzy Logic Based Anomaly Detection for Embedded Network Security Cyber Sensor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ondrej Linda; Todd Vollmer; Jason Wright
Resiliency and security in critical infrastructure control systems in the modern world of cyber terrorism constitute a relevant concern. Developing a network security system specifically tailored to the requirements of such critical assets is of a primary importance. This paper proposes a novel learning algorithm for anomaly based network security cyber sensor together with its hardware implementation. The presented learning algorithm constructs a fuzzy logic rule based model of normal network behavior. Individual fuzzy rules are extracted directly from the stream of incoming packets using an online clustering algorithm. This learning algorithm was specifically developed to comply with the constrainedmore » computational requirements of low-cost embedded network security cyber sensors. The performance of the system was evaluated on a set of network data recorded from an experimental test-bed mimicking the environment of a critical infrastructure control system.« less
NASA Astrophysics Data System (ADS)
Tamura, Yoshinobu; Yamada, Shigeru
OSS (open source software) systems which serve as key components of critical infrastructures in our social life are still ever-expanding now. Especially, embedded OSS systems have been gaining a lot of attention in the embedded system area, i.e., Android, BusyBox, TRON, etc. However, the poor handling of quality problem and customer support prohibit the progress of embedded OSS. Also, it is difficult for developers to assess the reliability and portability of embedded OSS on a single-board computer. In this paper, we propose a method of software reliability assessment based on flexible hazard rates for the embedded OSS. Also, we analyze actual data of software failure-occurrence time-intervals to show numerical examples of software reliability assessment for the embedded OSS. Moreover, we compare the proposed hazard rate model for the embedded OSS with the typical conventional hazard rate models by using the comparison criteria of goodness-of-fit. Furthermore, we discuss the optimal software release problem for the porting-phase based on the total expected software maintenance cost.
Learning from failure in health care: frequent opportunities, pervasive barriers.
Edmondson, A C
2004-12-01
The notion that hospitals and medical practices should learn from failures, both their own and others', has obvious appeal. Yet, healthcare organisations that systematically and effectively learn from the failures that occur in the care delivery process, especially from small mistakes and problems rather than from consequential adverse events, are rare. This article explores pervasive barriers embedded in healthcare's organisational systems that make shared or organisational learning from failure difficult and then recommends strategies for overcoming these barriers to learning from failure, emphasising the critical role of leadership. Firstly, leaders must create a compelling vision that motivates and communicates urgency for change; secondly, leaders must work to create an environment of psychological safety that fosters open reporting, active questioning, and frequent sharing of insights and concerns; and thirdly, case study research on one hospital's organisational learning initiative suggests that leaders can empower and support team learning throughout their organisations as a way of identifying, analysing, and removing hazards that threaten patient safety.
Learning from failure in health care: frequent opportunities, pervasive barriers
Edmondson, A
2004-01-01
The notion that hospitals and medical practices should learn from failures, both their own and others', has obvious appeal. Yet, healthcare organisations that systematically and effectively learn from the failures that occur in the care delivery process, especially from small mistakes and problems rather than from consequential adverse events, are rare. This article explores pervasive barriers embedded in healthcare's organisational systems that make shared or organisational learning from failure difficult and then recommends strategies for overcoming these barriers to learning from failure, emphasising the critical role of leadership. Firstly, leaders must create a compelling vision that motivates and communicates urgency for change; secondly, leaders must work to create an environment of psychological safety that fosters open reporting, active questioning, and frequent sharing of insights and concerns; and thirdly, case study research on one hospital's organisational learning initiative suggests that leaders can empower and support team learning throughout their organisations as a way of identifying, analysing, and removing hazards that threaten patient safety. PMID:15576689
NASA Technical Reports Server (NTRS)
Torres-Pomales, Wilfredo
2014-01-01
A system is safety-critical if its failure can endanger human life or cause significant damage to property or the environment. State-of-the-art computer systems on commercial aircraft are highly complex, software-intensive, functionally integrated, and network-centric systems of systems. Ensuring that such systems are safe and comply with existing safety regulations is costly and time-consuming as the level of rigor in the development process, especially the validation and verification activities, is determined by considerations of system complexity and safety criticality. A significant degree of care and deep insight into the operational principles of these systems is required to ensure adequate coverage of all design implications relevant to system safety. Model-based development methodologies, methods, tools, and techniques facilitate collaboration and enable the use of common design artifacts among groups dealing with different aspects of the development of a system. This paper examines the application of model-based development to complex and safety-critical aircraft computer systems. Benefits and detriments are identified and an overall assessment of the approach is given.
Bennett, Linda Rae
2017-01-01
In this article I demonstrate what can be learned from the indigenous healing knowledge and practices of traditional Sasak midwives on Lombok island in eastern Indonesia. I focus on the treatment of infertility, contrasting the differential experiences of Sasak women when they consult traditional midwives and biomedical doctors. Women's and midwives' perspectives provide critical insight into how cultural safety is both constituted and compromised in the context of reproductive health care. Core components of cultural safety embedded in the practices of traditional midwives include the treatment of women as embodied subjects rather than objectified bodies, and privileging physical contact as a healing modality. Cultural safety also encompasses respect for women's privacy and bodily dignity, as well as two-way and narrative communication styles. Local understandings of cultural safety have great potential to improve the routine practices of doctors, particularly in relation to doctor-patient communication and protocols for conducting pelvic exams.
Tank waste remediation system nuclear criticality safety program management review
DOE Office of Scientific and Technical Information (OSTI.GOV)
BRADY RAAP, M.C.
1999-06-24
This document provides the results of an internal management review of the Tank Waste Remediation System (TWRS) criticality safety program, performed in advance of the DOE/RL assessment for closure of the TWRS Nuclear Criticality Safety Issue, March 1994. Resolution of the safety issue was identified as Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-40-12, due September 1999.
Code of Federal Regulations, 2012 CFR
2012-10-01
... system technology. However, a subsystem or component of an office system must comply with the requirements of this subpart if it performs safety-critical functions within, or affects the safety performance... this subpart if they result in a degradation of safety or a material increase in safety-critical...
Code of Federal Regulations, 2011 CFR
2011-10-01
... system technology. However, a subsystem or component of an office system must comply with the requirements of this subpart if it performs safety-critical functions within, or affects the safety performance... this subpart if they result in a degradation of safety or a material increase in safety-critical...
Code of Federal Regulations, 2013 CFR
2013-10-01
... system technology. However, a subsystem or component of an office system must comply with the requirements of this subpart if it performs safety-critical functions within, or affects the safety performance... this subpart if they result in a degradation of safety or a material increase in safety-critical...
Code of Federal Regulations, 2014 CFR
2014-10-01
... system technology. However, a subsystem or component of an office system must comply with the requirements of this subpart if it performs safety-critical functions within, or affects the safety performance... this subpart if they result in a degradation of safety or a material increase in safety-critical...
Code of Federal Regulations, 2010 CFR
2010-10-01
... system technology. However, a subsystem or component of an office system must comply with the requirements of this subpart if it performs safety-critical functions within, or affects the safety performance... this subpart if they result in a degradation of safety or a material increase in safety-critical...
A method for identifying EMI critical circuits during development of a large C3
NASA Astrophysics Data System (ADS)
Barr, Douglas H.
The circuit analysis methods and process Boeing Aerospace used on a large, ground-based military command, control, and communications (C3) system are described. This analysis was designed to help identify electromagnetic interference (EMI) critical circuits. The methodology used the MIL-E-6051 equipment criticality categories as the basis for defining critical circuits, relational database technology to help sort through and account for all of the approximately 5000 system signal cables, and Macintosh Plus personal computers to predict critical circuits based on safety margin analysis. The EMI circuit analysis process systematically examined all system circuits to identify which ones were likely to be EMI critical. The process used two separate, sequential safety margin analyses to identify critical circuits (conservative safety margin analysis, and detailed safety margin analysis). These analyses used field-to-wire and wire-to-wire coupling models using both worst-case and detailed circuit parameters (physical and electrical) to predict circuit safety margins. This process identified the predicted critical circuits that could then be verified by test.
Software Safety Risk in Legacy Safety-Critical Computer Systems
NASA Technical Reports Server (NTRS)
Hill, Janice L.; Baggs, Rhoda
2007-01-01
Safety Standards contain technical and process-oriented safety requirements. Technical requirements are those such as "must work" and "must not work" functions in the system. Process-Oriented requirements are software engineering and safety management process requirements. Address the system perspective and some cover just software in the system > NASA-STD-8719.13B Software Safety Standard is the current standard of interest. NASA programs/projects will have their own set of safety requirements derived from the standard. Safety Cases: a) Documented demonstration that a system complies with the specified safety requirements. b) Evidence is gathered on the integrity of the system and put forward as an argued case. [Gardener (ed.)] c) Problems occur when trying to meet safety standards, and thus make retrospective safety cases, in legacy safety-critical computer systems.
2007-06-01
study), so tags placed in the fuze will allow both munitions to be tagged. • Fuze modification : o Four equally spaced grooves, 0.32 inches deep...investigation. Therefore, effort must continue to verify all recommendations before implementing the modifications . The list below highlights critical...concerns that require attention and verification: • Environmental o Manufacturing modifications to attach the tag Worker safety Bio friendliness o
Modeling and Analysis of Mixed Synchronous/Asynchronous Systems
NASA Technical Reports Server (NTRS)
Driscoll, Kevin R.; Madl. Gabor; Hall, Brendan
2012-01-01
Practical safety-critical distributed systems must integrate safety critical and non-critical data in a common platform. Safety critical systems almost always consist of isochronous components that have synchronous or asynchronous interface with other components. Many of these systems also support a mix of synchronous and asynchronous interfaces. This report presents a study on the modeling and analysis of asynchronous, synchronous, and mixed synchronous/asynchronous systems. We build on the SAE Architecture Analysis and Design Language (AADL) to capture architectures for analysis. We present preliminary work targeted to capture mixed low- and high-criticality data, as well as real-time properties in a common Model of Computation (MoC). An abstract, but representative, test specimen system was created as the system to be modeled.
Results from an Independent View on The Validation of Safety-Critical Space Systems
NASA Astrophysics Data System (ADS)
Silva, N.; Lopes, R.; Esper, A.; Barbosa, R.
2013-08-01
The Independent verification and validation (IV&V) has been a key process for decades, and is considered in several international standards. One of the activities described in the “ESA ISVV Guide” is the independent test verification (stated as Integration/Unit Test Procedures and Test Data Verification). This activity is commonly overlooked since customers do not really see the added value of checking thoroughly the validation team work (could be seen as testing the tester's work). This article presents the consolidated results of a large set of independent test verification activities, including the main difficulties, results obtained and advantages/disadvantages for the industry of these activities. This study will support customers in opting-in or opting-out for this task in future IV&V contracts since we provide concrete results from real case studies in the space embedded systems domain.
DOE Office of Scientific and Technical Information (OSTI.GOV)
DAVIS, S.J.
2000-12-28
This document identifies critical characteristics of components to be dedicated for use in Safety Significant (SS) Systems, Structures, or Components (SSCs). This document identifies the requirements for the components of the common, radiation area, monitor alarm in the WESF pool cell. These are procured as Commercial Grade Items (CGI), with the qualification testing and formal dedication to be performed at the Waste Encapsulation Storage Facility (WESF) for use in safety significant systems. System modifications are to be performed in accordance with the approved design. Components for this change are commercially available and interchangeable with the existing alarm configuration This documentmore » focuses on the operational requirements for alarm, declaration of the safety classification, identification of critical characteristics, and interpretation of requirements for procurement. Critical characteristics are identified herein and must be verified, followed by formal dedication, prior to the components being used in safety related applications.« less
Product Engineering Class in the Software Safety Risk Taxonomy for Building Safety-Critical Systems
NASA Technical Reports Server (NTRS)
Hill, Janice; Victor, Daniel
2008-01-01
When software safety requirements are imposed on legacy safety-critical systems, retrospective safety cases need to be formulated as part of recertifying the systems for further use and risks must be documented and managed to give confidence for reusing the systems. The SEJ Software Development Risk Taxonomy [4] focuses on general software development issues. It does not, however, cover all the safety risks. The Software Safety Risk Taxonomy [8] was developed which provides a construct for eliciting and categorizing software safety risks in a straightforward manner. In this paper, we present extended work on the taxonomy for safety that incorporates the additional issues inherent in the development and maintenance of safety-critical systems with software. An instrument called a Software Safety Risk Taxonomy Based Questionnaire (TBQ) is generated containing questions addressing each safety attribute in the Software Safety Risk Taxonomy. Software safety risks are surfaced using the new TBQ and then analyzed. In this paper we give the definitions for the specialized Product Engineering Class within the Software Safety Risk Taxonomy. At the end of the paper, we present the tool known as the 'Legacy Systems Risk Database Tool' that is used to collect and analyze the data required to show traceability to a particular safety standard
MISSION: Mission and Safety Critical Support Environment. Executive overview
NASA Technical Reports Server (NTRS)
Mckay, Charles; Atkinson, Colin
1992-01-01
For mission and safety critical systems it is necessary to: improve definition, evolution and sustenance techniques; lower development and maintenance costs; support safe, timely and affordable system modifications; and support fault tolerance and survivability. The goal of the MISSION project is to lay the foundation for a new generation of integrated systems software providing a unified infrastructure for mission and safety critical applications and systems. This will involve the definition of a common, modular target architecture and a supporting infrastructure.
Code of Federal Regulations, 2013 CFR
2013-10-01
..., the Officer of the Navigational Watch, or GMDSS Operator on watch, shall update the embedded position... (vessels subject to the Global Maritime Distress and Safety System (GMDSS) should also refer to subpart W...
Code of Federal Regulations, 2014 CFR
2014-10-01
..., the Officer of the Navigational Watch, or GMDSS Operator on watch, shall update the embedded position... (vessels subject to the Global Maritime Distress and Safety System (GMDSS) should also refer to subpart W...
Designing the modern pump: engineering aspects of continuous subcutaneous insulin infusion software.
Welsh, John B; Vargas, Steven; Williams, Gary; Moberg, Sheldon
2010-06-01
Insulin delivery systems attracted the efforts of biological, mechanical, electrical, and software engineers well before they were commercially viable. The introduction of the first commercial insulin pump in 1983 represents an enduring milestone in the history of diabetes management. Since then, pumps have become much more than motorized syringes and have assumed a central role in diabetes management by housing data on insulin delivery and glucose readings, assisting in bolus estimation, and interfacing smoothly with humans and compatible devices. Ensuring the integrity of the embedded software that controls these devices is critical to patient safety and regulatory compliance. As pumps and related devices evolve, software engineers will face challenges and opportunities in designing pumps that are safe, reliable, and feature-rich. The pumps and related systems must also satisfy end users, healthcare providers, and regulatory authorities. In particular, pumps that are combined with glucose sensors and appropriate algorithms will provide the basis for increasingly safe and precise automated insulin delivery-essential steps to developing a fully closed-loop system.
A traffic situation analysis system
NASA Astrophysics Data System (ADS)
Sidla, Oliver; Rosner, Marcin
2011-01-01
The observation and monitoring of traffic with smart visions systems for the purpose of improving traffic safety has a big potential. For example embedded vision systems built into vehicles can be used as early warning systems, or stationary camera systems can modify the switching frequency of signals at intersections. Today the automated analysis of traffic situations is still in its infancy - the patterns of vehicle motion and pedestrian flow in an urban environment are too complex to be fully understood by a vision system. We present steps towards such a traffic monitoring system which is designed to detect potentially dangerous traffic situations, especially incidents in which the interaction of pedestrians and vehicles might develop into safety critical encounters. The proposed system is field-tested at a real pedestrian crossing in the City of Vienna for the duration of one year. It consists of a cluster of 3 smart cameras, each of which is built from a very compact PC hardware system in an outdoor capable housing. Two cameras run vehicle detection software including license plate detection and recognition, one camera runs a complex pedestrian detection and tracking module based on the HOG detection principle. As a supplement, all 3 cameras use additional optical flow computation in a low-resolution video stream in order to estimate the motion path and speed of objects. This work describes the foundation for all 3 different object detection modalities (pedestrians, vehi1cles, license plates), and explains the system setup and its design.
NASA Astrophysics Data System (ADS)
Rainieri, Carlo; Song, Yi; Fabbrocino, Giovanni; Schulz, Mark J.; Shanov, Vesselin
2013-08-01
Degradation phenomena can affect civil structures over their lifespan. The recent advances in nanotechnology and sensing allow to monitor the behaviour of a structure, assess its performance and identify damage at an early stage. Thus, maintenance actions can be carried out in a timely manner, improving structural reliability and safety. Structural Health Monitoring (SHM) is traditionally performed at a global level, with a limited number of sensors distributed over a relatively large area of a structure. Thus, only major damage conditions are detectable. Dense sensor networks and innovative structural neural systems, reproducing the structure and the function of the human nervous system, may overcome this drawback of current SHM systems. Miniaturization and embedment are key requirements for successful implementation of structural neural systems. Carbon nanotubes (CNTs) can play an attractive role in the development of embedded sensors and smart structural materials, since they can provide to traditional cement based materials both structural capability and measurable response to applied stresses, strains, cracks and other flaws. In this paper investigations about CNT/cement composites and their self-sensing capabilities are summarized and critically revised. The analysis of available experimental results and theoretical developments provides useful design criteria for the fabrication of CNT/cement composites optimized for SHM applications in civil engineering. Specific attention is paid to the opportunities provided by new RF plasma technologies for the functionalization of CNTs in view of sensor development and SHM applications.
Bouma, Helen; López López, Mónica; Knorth, Erik J; Grietens, Hans
2018-05-01
Policymakers are increasingly focusing on the participation of children in the child protection system (CPS). However, research shows that actual practice still needs to be improved. Embedding children's participation in legislation and policy documents is one important prerequisite for achieving meaningful participation in child protection practice. In this study, the participation of children in the Dutch CPS under the new Youth Act 2015 is critically analyzed. National legislation and policy documents were studied using a model of "meaningful participation" based on article 12 of the UNCRC. Results show that the idea of children's participation is deeply embedded in the current Dutch CPS. However, Dutch policy documents do not fully cover the three dimensions of what is considered to be meaningful participation for children: informing, hearing, and involving. Furthermore, children's participation differs among the organizations included in the child protection chain. A clear overall policy concerning the participation of children in the Dutch CPS is lacking. The conclusions of this critical analysis of policy documents and the framework of meaningful participation presented may provide a basis for the embedding of meaningful participation for children in child protection systems of other countries. Copyright © 2018 Elsevier Ltd. All rights reserved.
Damage Detection Sensor System for Aerospace and Multiple Applications
NASA Technical Reports Server (NTRS)
Williams, Martha; Lewis, Mark; Gibson, Tracy L.; Lane, John; Medelius, Pedro
2017-01-01
NASA has identified structural health monitoring and damage detection and verification as critical needs in multiple technology roadmaps. The sensor systems can be customized for detecting location, damage size, and depth, with velocity options and can be designed for particular environments for monitoring of impact or physical damage to a structure. The damage detection system has been successfully demonstrated in a harsh environment and remote integration tested over 1000 miles apart. Multiple applications includes: Spacecraft and Aircraft; Inflatable, Deployable and Expandable Structures; Space Debris Monitoring; Space Habitats; Military Shelters; Solar Arrays, Smart Garments and Wearables, Extravehicular activity (EVA) suits; Critical Hardware Enclosures; Embedded Composite Structures; and Flexible Hybrid Printed Electronics and Systems. For better implementation and infusion into more flexible architectures, important and improved designs in advancing embedded software and GUI interface, and increasing flexibility, modularity, and configurable capabilities of the system are currently being carried out.
Safety Hazards During Intrahospital Transport: A Prospective Observational Study.
Bergman, Lina M; Pettersson, Monica E; Chaboyer, Wendy P; Carlström, Eric D; Ringdal, Mona L
2017-10-01
To identify, classify, and describe safety hazards during the process of intrahospital transport of critically ill patients. A prospective observational study. Data from participant observations of the intrahospital transport process were collected over a period of 3 months. The study was undertaken at two ICUs in one university hospital. Critically ill patients transported within the hospital by critical care nurses, unlicensed nurses, and physicians. None. Content analysis was performed using deductive and inductive approaches. We detected a total of 365 safety hazards (median, 7; interquartile range, 4-10) during 51 intrahospital transports of critically ill patients, 80% of whom were mechanically ventilated. The majority of detected safety hazards were assessed as increasing the risk of harm, compromising patient safety (n = 204). Using the System Engineering Initiative for Patient Safety, we identified safety hazards related to the work system, as follows: team (n = 61), tasks (n = 83), tools and technologies (n = 124), environment (n = 48), and organization (n = 49). Inductive analysis provided an in-depth description of those safety hazards, contributing factors, and process-related outcomes. Findings suggest that intrahospital transport is a hazardous process for critically ill patients. We have identified several factors that may contribute to transport-related adverse events, which will provide the opportunity for the redesign of systems to enhance patient safety.
Coldwell, T; Cole, P; Edwards, C; Makepeace, J; Murdock, C; Odams, H; Whitcher, R; Willis, S; Yates, L
2015-12-01
The safety culture of any organisation plays a critical role in setting the tone for both effective delivery of service and high standards of performance. By embedding safety at a cultural level, organisations are able to influence the attitudes and behaviours of stakeholders. To achieve this requires the ongoing commitment of heads of organisations and also individuals to prioritise safety no less than other competing goals (e.g. in universities, recruitment and retention are key) to ensure the protection of both people and the environment. The concept of culture is the same whatever the sector, e.g. medical, nuclear, industry, education, and research, but the higher education and research sectors within the UK are a unique challenge in developing a strong safety culture. This report provides an overview of the challenges presented by the sector, the current status of radiation protection culture, case studies to demonstrate good and bad practice in the sector and the practical methods to influence change.
Research on memory management in embedded systems
NASA Astrophysics Data System (ADS)
Huang, Xian-ying; Yang, Wu
2005-12-01
Memory is a scarce resource in embedded system due to cost and size. Thus, applications in embedded systems cannot use memory randomly, such as in desktop applications. However, data and code must be stored into memory for running. The purpose of this paper is to save memory in developing embedded applications and guarantee running under limited memory conditions. Embedded systems often have small memory and are required to run a long time. Thus, a purpose of this study is to construct an allocator that can allocate memory effectively and bear a long-time running situation, reduce memory fragmentation and memory exhaustion. Memory fragmentation and exhaustion are related to the algorithm memory allocated. Static memory allocation cannot produce fragmentation. In this paper it is attempted to find an effective allocation algorithm dynamically, which can reduce memory fragmentation. Data is the critical part that ensures an application can run regularly, which takes up a large amount of memory. The amount of data that can be stored in the same size of memory is relevant with the selected data structure. Skills for designing application data in mobile phone are explained and discussed also.
The Department of Energy Nuclear Criticality Safety Program
NASA Astrophysics Data System (ADS)
Felty, James R.
2005-05-01
This paper broadly covers key events and activities from which the Department of Energy Nuclear Criticality Safety Program (NCSP) evolved. The NCSP maintains fundamental infrastructure that supports operational criticality safety programs. This infrastructure includes continued development and maintenance of key calculational tools, differential and integral data measurements, benchmark compilation, development of training resources, hands-on training, and web-based systems to enhance information preservation and dissemination. The NCSP was initiated in response to Defense Nuclear Facilities Safety Board Recommendation 97-2, Criticality Safety, and evolved from a predecessor program, the Nuclear Criticality Predictability Program, that was initiated in response to Defense Nuclear Facilities Safety Board Recommendation 93-2, The Need for Critical Experiment Capability. This paper also discusses the role Dr. Sol Pearlstein played in helping the Department of Energy lay the foundation for a robust and enduring criticality safety infrastructure.
Ginsburg, Liane R; Dhingra-Kumar, Neelam; Donaldson, Liam J
2017-01-01
Objectives The improvement of safety in healthcare worldwide depends in part on the knowledge, skills and attitudes of staff providing care. Greater patient safety content in health professional education and training programmes has been advocated internationally. While WHO Patient Safety Curriculum Guides (for Medical Schools and Multi-Professional Curricula) have been widely disseminated in low-income and middle-income countries (LMICs) over the last several years, little is known about patient safety curriculum implementation beyond high-income countries. The present study examines patient safety curriculum implementation in LMICs. Methods Two cross-sectional surveys were carried out. First, 88 technical officers in Ministries of Health and WHO country offices were surveyed to identify the pattern of patient safety curricula at country level. A second survey followed that gathered information from 71 people in a position to provide institution-level perspectives on patient safety curriculum implementation. Results The majority, 69% (30/44), of the countries were either considering whether to implement a patient safety curriculum or actively planning, rather than actually implementing, or embedding one. Most organisations recognised the need for patient safety education and training and felt a safety curriculum was compatible with the values of their organisation; however, important faculty-level barriers to patient safety curriculum implementation were identified. Key structural markers, such as dedicated financial resources and relevant assessment tools to evaluate trainees’ patient safety knowledge and skills, were in place in fewer than half of organisations studied. Conclusions Greater attention to patient safety curriculum implementation is needed. The barriers to patient safety curriculum implementation we identified in LMICs are not unique to these regions. We propose a framework to act as a global standard for patient safety curriculum implementation. Educating leaders through the system in order to embed patient safety culture in education and clinical settings is a critical first step. PMID:28619782
Integrated Software Health Management for Aircraft GN and C
NASA Technical Reports Server (NTRS)
Schumann, Johann; Mengshoel, Ole
2011-01-01
Modern aircraft rely heavily on dependable operation of many safety-critical software components. Despite careful design, verification and validation (V&V), on-board software can fail with disastrous consequences if it encounters problematic software/hardware interaction or must operate in an unexpected environment. We are using a Bayesian approach to monitor the software and its behavior during operation and provide up-to-date information about the health of the software and its components. The powerful reasoning mechanism provided by our model-based Bayesian approach makes reliable diagnosis of the root causes possible and minimizes the number of false alarms. Compilation of the Bayesian model into compact arithmetic circuits makes SWHM feasible even on platforms with limited CPU power. We show initial results of SWHM on a small simulator of an embedded aircraft software system, where software and sensor faults can be injected.
RICIS Symposium 1992: Mission and Safety Critical Systems Research and Applications
NASA Technical Reports Server (NTRS)
1992-01-01
This conference deals with computer systems which control systems whose failure to operate correctly could produce the loss of life and or property, mission and safety critical systems. Topics covered are: the work of standards groups, computer systems design and architecture, software reliability, process control systems, knowledge based expert systems, and computer and telecommunication protocols.
Acoustic Techniques for Structural Health Monitoring
NASA Astrophysics Data System (ADS)
Frankenstein, B.; Augustin, J.; Hentschel, D.; Schubert, F.; Köhler, B.; Meyendorf, N.
2008-02-01
Future safety and maintenance strategies for industrial components and vehicles are based on combinations of monitoring systems that are permanently attached to or embedded in the structure, and periodic inspections. The latter belongs to conventional nondestructive evaluation (NDE) and can be enhanced or partially replaced by structural health monitoring systems. However, the main benefit of this technology for the future will consist of systems that can be differently designed based on improved safety philosophies, including continuous monitoring. This approach will increase the efficiency of inspection procedures at reduced inspection times. The Fraunhofer IZFP Dresden Branch has developed network nodes, miniaturized transmitter and receiver systems for active and passive acoustical techniques and sensor systems that can be attached to or embedded into components or structures. These systems have been used to demonstrate intelligent sensor networks for the monitoring of aerospace structures, railway systems, wind energy generators, piping system and other components. Material discontinuities and flaws have been detected and monitored during full scale fatigue testing. This paper will discuss opportunities and future trends in nondestructive evaluation and health monitoring based on new sensor principles and advanced microelectronics. It will outline various application examples of monitoring systems based on acoustic techniques and will indicate further needs for research and development.
Assurance of Fault Management: Risk-Significant Adverse Condition Awareness
NASA Technical Reports Server (NTRS)
Fitz, Rhonda
2016-01-01
Fault Management (FM) systems are ranked high in risk-based assessment of criticality within flight software, emphasizing the importance of establishing highly competent domain expertise to provide assurance for NASA projects, especially as spaceflight systems continue to increase in complexity. Insight into specific characteristics of FM architectures seen embedded within safety- and mission-critical software systems analyzed by the NASA Independent Verification Validation (IVV) Program has been enhanced with an FM Technical Reference (TR) suite. Benefits are aimed beyond the IVV community to those that seek ways to efficiently and effectively provide software assurance to reduce the FM risk posture of NASA and other space missions. The identification of particular FM architectures, visibility, and associated IVV techniques provides a TR suite that enables greater assurance that critical software systems will adequately protect against faults and respond to adverse conditions. The role FM has with regard to overall asset protection of flight software systems is being addressed with the development of an adverse condition (AC) database encompassing flight software vulnerabilities.Identification of potential off-nominal conditions and analysis to determine how a system responds to these conditions are important aspects of hazard analysis and fault management. Understanding what ACs the mission may face, and ensuring they are prevented or addressed is the responsibility of the assurance team, which necessarily should have insight into ACs beyond those defined by the project itself. Research efforts sponsored by NASAs Office of Safety and Mission Assurance defined terminology, categorized data fields, and designed a baseline repository that centralizes and compiles a comprehensive listing of ACs and correlated data relevant across many NASA missions. This prototype tool helps projects improve analysis by tracking ACs, and allowing queries based on project, mission type, domain component, causal fault, and other key characteristics. The repository has a firm structure, initial collection of data, and an interface established for informational queries, with plans for integration within the Enterprise Architecture at NASA IVV, enabling support and accessibility across the Agency. The development of an improved workflow process for adaptive, risk-informed FM assurance is currently underway.
Providing Nuclear Criticality Safety Analysis Education through Benchmark Experiment Evaluation
DOE Office of Scientific and Technical Information (OSTI.GOV)
John D. Bess; J. Blair Briggs; David W. Nigg
2009-11-01
One of the challenges that today's new workforce of nuclear criticality safety engineers face is the opportunity to provide assessment of nuclear systems and establish safety guidelines without having received significant experience or hands-on training prior to graduation. Participation in the International Criticality Safety Benchmark Evaluation Project (ICSBEP) and/or the International Reactor Physics Experiment Evaluation Project (IRPhEP) provides students and young professionals the opportunity to gain experience and enhance critical engineering skills.
A Byzantine-Fault Tolerant Self-Stabilizing Protocol for Distributed Clock Synchronization Systems
NASA Technical Reports Server (NTRS)
Malekpour, Mahyar R.
2006-01-01
Embedded distributed systems have become an integral part of safety-critical computing applications, necessitating system designs that incorporate fault tolerant clock synchronization in order to achieve ultra-reliable assurance levels. Many efficient clock synchronization protocols do not, however, address Byzantine failures, and most protocols that do tolerate Byzantine failures do not self-stabilize. Of the Byzantine self-stabilizing clock synchronization algorithms that exist in the literature, they are based on either unjustifiably strong assumptions about initial synchrony of the nodes or on the existence of a common pulse at the nodes. The Byzantine self-stabilizing clock synchronization protocol presented here does not rely on any assumptions about the initial state of the clocks. Furthermore, there is neither a central clock nor an externally generated pulse system. The proposed protocol converges deterministically, is scalable, and self-stabilizes in a short amount of time. The convergence time is linear with respect to the self-stabilization period. Proofs of the correctness of the protocol as well as the results of formal verification efforts are reported.
Y-12 PLANT NUCLEAR SAFETY HANDBOOK
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wachter, J.W. ed.; Bailey, M.L.; Cagle, T.J.
1963-03-27
Information needed to solve nuclear safety problems is condensed into a reference book for use by persons familiar with the field. Included are a glossary of terms; useful tables; nuclear constants; criticality calculations; basic nuclear safety limits; solution geometries and critical values; metal critical values; criticality values for intermediate, heterogeneous, and interacting systems; miscellaneous and related information; and report number, author, and subject indexes. (C.H.)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grebogi, C.; Yorke, J.A.
This report discusses the following topics: controlling chaotic dynamical systems; embedding of experimental data; effect of noise on critical exponents of crises; transition to chaotic scattering; and distribution of floaters on a fluid surface. (LSP)
Four Pillars for Improving the Quality of Safety-Critical Software-Reliant Systems
2013-04-01
Studies of safety-critical software-reliant systems developed using the current practices of build-then-test show that requirements and architecture ... design defects make up approximately 70% of all defects, many system level related to operational quality attributes, and 80% of these defects are
Rethinking healthcare as a safety--critical industry.
Lwears, Robert
2012-01-01
The discipline of ergonomics, or human factors engineering, has made substantial contributions to both the development of a science of safety, and to the improvement of safety in a wide variety of hazardous industries, including nuclear power, aviation, shipping, energy extraction and refining, military operations, and finance. It is notable that healthcare, which in most advanced societies is a substantial sector of the economy (eg, 15% of US gross domestic product) and has been associated with large volumes of potentially preventable morbidity and mortality, has heretofore not been viewed as a safety-critical industry. This paper proposes that improving safety performance in healthcare must involve a re-envisioning of healthcare itself as a safety-critical industry, but one with considerable differences from most engineered safety-critical systems. This has implications both for healthcare, and for conceptions of safety-critical industries.
A Practical Risk Assessment Methodology for Safety-Critical Train Control Systems
DOT National Transportation Integrated Search
2009-07-01
This project proposes a Practical Risk Assessment Methodology (PRAM) for analyzing railroad accident data and assessing the risk and benefit of safety-critical train control systems. This report documents in simple steps the algorithms and data input...
49 CFR 533.6 - Measurement and calculation procedures.
Code of Federal Regulations, 2014 CFR
2014-10-01
... the technology is related to crash-avoidance technologies, safety critical systems or systems affecting safety-critical functions, or technologies designed for the purpose of reducing the frequency of... improvements related to air conditioning efficiency, off-cycle technologies, and hybridization and other...
NASA Astrophysics Data System (ADS)
Arief, I. S.; Suherman, I. H.; Wardani, A. Y.; Baidowi, A.
2017-05-01
Control and monitoring system is a continuous process of securing the asset in the Marine Current Renewable Energy. A control and monitoring system is existed each critical components which is embedded in Failure Mode Effect Analysis (FMEA) method. As the result, the process in this paper developed through a matrix sensor. The matrix correlated to critical components and monitoring system which supported by sensors to conduct decision-making.
A Framework for Evaluating Regional-Scale Numerical Photochemical Modeling Systems
This paper discusses the need for critically evaluating regional-scale (~ 200-2000 km) three dimensional numerical photochemical air quality modeling systems to establish a model's credibility in simulating the spatio-temporal features embedded in the observations. Because of li...
Criticality Safety Evaluation for the TACS at DAF
DOE Office of Scientific and Technical Information (OSTI.GOV)
Percher, C. M.; Heinrichs, D. P.
2011-06-10
Hands-on experimental training in the physical behavior of multiplying systems is one of ten key areas of training required for practitioners to become qualified in the discipline of criticality safety as identified in DOE-STD-1135-99, Guidance for Nuclear Criticality Safety Engineer Training and Qualification. This document is a criticality safety evaluation of the training activities and operations associated with HS-3201-P, Nuclear Criticality 4-Day Training Course (Practical). This course was designed to also address the training needs of nuclear criticality safety professionals under the auspices of the NNSA Nuclear Criticality Safety Program1. The hands-on, or laboratory, portion of the course will utilizemore » the Training Assembly for Criticality Safety (TACS) and will be conducted in the Device Assembly Facility (DAF) at the Nevada Nuclear Security Site (NNSS). The training activities will be conducted by Lawrence Livermore National Laboratory following the requirements of an Integrated Work Sheet (IWS) and associated Safety Plan. Students will be allowed to handle the fissile material under the supervision of an LLNL Certified Fissile Material Handler.« less
What Is John Dewey Doing in "To Kill a Mockingbird"?
ERIC Educational Resources Information Center
Frank, Jeff
2015-01-01
Harper Lee's novel "To Kill a Mockingbird" is taught in countless public schools and is beloved by many teachers and future teachers. Embedded within this novel--interestingly--is a strong criticism of an approach to education mockingly referred to as the "Dewey Decimal System." In this essay I explore Lee's criticism of…
On Space Exploration and Human Error: A Paper on Reliability and Safety
NASA Technical Reports Server (NTRS)
Bell, David G.; Maluf, David A.; Gawdiak, Yuri
2005-01-01
NASA space exploration should largely address a problem class in reliability and risk management stemming primarily from human error, system risk and multi-objective trade-off analysis, by conducting research into system complexity, risk characterization and modeling, and system reasoning. In general, in every mission we can distinguish risk in three possible ways: a) known-known, b) known-unknown, and c) unknown-unknown. It is probably almost certain that space exploration will partially experience similar known or unknown risks embedded in the Apollo missions, Shuttle or Station unless something alters how NASA will perceive and manage safety and reliability
49 CFR 533.6 - Measurement and calculation procedures.
Code of Federal Regulations, 2013 CFR
2013-10-01
... technology is related to crash-avoidance technologies, safety critical systems or systems affecting safety-critical functions, or technologies designed for the purpose of reducing the frequency of vehicle crashes... improvements related to air conditioning efficiency, off-cycle technologies, and hybridization and other...
Design and implement of pack filter module base on embedded firewall
NASA Astrophysics Data System (ADS)
Tian, Libo; Wang, Chen; Yang, Shunbo
2011-10-01
In the traditional security solution conditions, software firewall cannot intercept and respond the invasion before being attacked. And because of the high cost, the hardware firewall does not apply to the security strategy of the end nodes, so we have designed a kind of solution of embedded firewall with hardware and software. With ARM embedding Linux operating system, we have designed packet filter module and intrusion detection module to implement the basic function of firewall. Experiments and results show that that firewall has the advantages of low cost, high processing speed, high safety and the application of the computer terminals. This paper focuses on packet filtering module design and implementation.
New research opportunities for roadside safety barriers improvement
NASA Astrophysics Data System (ADS)
Cantisani, Giuseppe; Di Mascio, Paola; Polidori, Carlo
2017-09-01
Among the major topics regarding the protection of roads, restraint systems still represent a big opportunity in order to increase safety performances. When accidents happen, in fact, the infrastructure can substantially contribute to the reduction of consequences if its marginal spaces are well designed and/or effective restraint systems are installed there. Nevertheless, basic concepts and technology of road safety barriers have not significantly changed for the last two decades. The paper proposes a new approach to the study aimed to define possible enhancements of restraint safety systems performances, by using new materials and defining innovative design principles. In particular, roadside systems can be developed with regard to vehicle-barrier interaction, vehicle-oriented design (included low-mass and extremely low-mass vehicles), traffic suitability, user protection, working width reduction. In addition, thanks to sensors embedded into the barriers, it is also expected to deal with new challenges related to the guidance of automatic vehicles and I2V communication.
Software Design Improvements. Part 2; Software Quality and the Design and Inspection Process
NASA Technical Reports Server (NTRS)
Lalli, Vincent R.; Packard, Michael H.; Ziemianski, Tom
1997-01-01
The application of assurance engineering techniques improves the duration of failure-free performance of software. The totality of features and characteristics of a software product are what determine its ability to satisfy customer needs. Software in safety-critical systems is very important to NASA. We follow the System Safety Working Groups definition for system safety software as: 'The optimization of system safety in the design, development, use and maintenance of software and its integration with safety-critical systems in an operational environment. 'If it is not safe, say so' has become our motto. This paper goes over methods that have been used by NASA to make software design improvements by focusing on software quality and the design and inspection process.
Andalam, Sidharta; Ramanna, Harshavardhan; Malik, Avinash; Roop, Parthasarathi; Patel, Nitish; Trew, Mark L
2016-08-01
Virtual heart models have been proposed for closed loop validation of safety-critical embedded medical devices, such as pacemakers. These models must react in real-time to off-the-shelf medical devices. Real-time performance can be obtained by implementing models in computer hardware, and methods of compiling classes of Hybrid Automata (HA) onto FPGA have been developed. Models of ventricular cardiac cell electrophysiology have been described using HA which capture the complex nonlinear behavior of biological systems. However, many models that have been used for closed-loop validation of pacemakers are highly abstract and do not capture important characteristics of the dynamic rate response. We developed a new HA model of cardiac cells which captures dynamic behavior and we implemented the model in hardware. This potentially enables modeling the heart with over 1 million dynamic cells, making the approach ideal for closed loop testing of medical devices.
An overheight vehicle bridge collision monitoring system using piezoelectric transducers
NASA Astrophysics Data System (ADS)
Song, G.; Olmi, C.; Gu, H.
2007-04-01
With increasing traffic volume follows an increase in the number of overheight truck collisions with highway bridges. The detection of collision impact and evaluation of the impact level is a critical issue in the maintenance of a concrete bridge. In this paper, an overheight collision detection and evaluation system is developed for concrete bridge girders using piezoelectric transducers. An electric circuit is designed to detect the impact and to activate a digital camera to take photos of the offending truck. Impact tests and a health monitoring test were conducted on a model concrete bridge girder by using three piezoelectric transducers embedded before casting. From the experimental data of the impact test, it can be seen that there is a linear relation between the output of sensor energy and the impact energy. The health monitoring results show that the proposed damage index indicates the level of damage inside the model concrete bridge girder. The proposed overheight truck-bridge collision detection and evaluation system has the potential to be applied to the safety monitoring of highway bridges.
Donovan, Sarah-Louise; Salmon, Paul M; Horberry, Timothy; Lenné, Michael G
2018-01-01
Safety leadership is an important factor in supporting safe performance in the workplace. The present case study examined the role of safety leadership during the Bingham Canyon Mine high-wall failure, a significant mining incident in which no fatalities or injuries were incurred. The Critical Decision Method (CDM) was used in conjunction with a self-reporting approach to examine safety leadership in terms of decisions, behaviours and actions that contributed to the incidents' safe outcome. Mapping the analysis onto Rasmussen's Risk Management Framework (Rasmussen, 1997), the findings demonstrate clear links between safety leadership decisions, and emergent behaviours and actions across the work system. Communication and engagement based decisions featured most prominently, and were linked to different leadership practices across the work system. Further, a core sub-set of CDM decision elements were linked to the open flow and exchange of information across the work system, which was critical to supporting the safe outcome. The findings provide practical implications for the development of safety leadership capability to support safety within the mining industry. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Rosenberg, Linda
1997-01-01
If software is a critical element in a safety critical system, it is imperative to implement a systematic approach to software safety as an integral part of the overall system safety programs. The NASA-STD-8719.13A, "NASA Software Safety Standard", describes the activities necessary to ensure that safety is designed into software that is acquired or developed by NASA, and that safety is maintained throughout the software life cycle. A PDF version, is available on the WWW from Lewis. A Guidebook that will assist in the implementation of the requirements in the Safety Standard is under development at the Lewis Research Center (LeRC). After completion, it will also be available on the WWW from Lewis.
Walton, Merrilyn; Harrison, Reema; Burgess, Annette; Foster, Kirsty
2015-10-01
Preventable harm is one of the top six health problems in the developed world. Developing patient safety skills and knowledge among advanced trainee doctors is critical. Clinical supervision is the main form of training for advanced trainees. The use of supervision to develop patient safety competence has not been established. To establish the use of clinical supervision and other workplace training to develop non-technical patient safety competency in advanced trainee doctors. Keywords, synonyms and subject headings were used to search eight electronic databases in addition to hand-searching of relevant journals up to 1 March 2014. Titles and abstracts of retrieved publications were screened by two reviewers and checked by a third. Full-text articles were screened against the eligibility criteria. Data on design, methods and key findings were extracted. Clinical supervision documents were assessed against components common to established patient safety frameworks. Findings from the reviewed articles and document analysis were collated in a narrative synthesis. Clinical supervision is not identified as an avenue for embedding patient safety skills in the workplace and is consequently not evaluated as a method to teach trainees these skills. Workplace training in non-technical patient safety skills is limited, but one-off training courses are sometimes used. Clinical supervision is the primary avenue for learning in postgraduate medical education but the most overlooked in the context of patient safety learning. The widespread implementation of short courses is not matched by evidence of rigorous evaluation. Supporting supervisors to identify teaching moments during supervision and to give weight to non-technical skills and technical skills equally is critical. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
DOT National Transportation Integrated Search
2014-12-01
In reinforced concrete systems, ensuring that a good bond between the : concrete and the embedded reinforcing steel is critical to long-term structural : performance. Without good bond between the two, the system simply cannot : behave as intended. :...
DOT National Transportation Integrated Search
2014-12-01
In reinforced concrete systems, ensuring that a good bond between the concrete and the embedded reinforcing steel is critical to : long-term structural performance. Without good bond between the two, the system simply cannot behave as intended. The b...
ERIC Educational Resources Information Center
Duggan, James R.
2014-01-01
The article engages with the opportunities and constraints raised by embedded research during times of rapid and extensive organisational change. Embedded research is an increasingly common approach for funding PhD studentships. The rapid and extensive reforms of the English public sector pose significant and underexplored challenges for embedded…
A Software Safety Risk Taxonomy for Use in Retrospective Safety Cases
NASA Technical Reports Server (NTRS)
Hill, Janice L.
2007-01-01
Safety standards contain technical and process-oriented safely requirements. The best time to include these requirements is early in the development lifecycle of the system. When software safety requirements are levied on a legacy system after the fact, a retrospective safety case will need to be constructed for the software in the system. This can be a difficult task because there may be few to no art facts available to show compliance to the software safely requirements. The risks associated with not meeting safely requirements in a legacy safely-critical computer system must be addressed to give confidence for reuse. This paper introduces a proposal for a software safely risk taxonomy for legacy safely-critical computer systems, by specializing the Software Engineering Institute's 'Software Development Risk Taxonomy' with safely elements and attributes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
White, W.F.
The purpose of this document is to provide the definition and means of maintaining the Safety Envelope (SE) related to the Criticality Alarm System (CAS). This document provides amplification of the Limiting Condition for Operation (LCO) described in the Plutonium Finishing Plant (PFP) Operational Safety Requirements (OSR), WHC-SD-CP-OSR-010, Rev. 0, 1994, Section 3.1.2, Criticality Detectors and Alarms. This document, with its appendices, provides the following: (1) System functional requirements for determining system operability (Section 3); (2) A list of annotated system block diagrams which indicate the safety envelope boundaries (Appendix C); (3) A list of the Safety Class 1 andmore » 2 Safety Envelope (SC-1/2 SE) equipment for input into the Master Component Index (Appendix B); (4) Functional requirements for individual SC-1/2 SE components, including appropriate setpoints and process parameters (Section 6 and Appendix A); (5) A list of the operational, maintenance and surveillance procedures necessary to operate and maintain the SC-1/2 SE components as required by the LCO (Section 6 and Appendix A).« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, P.B.; Yatabe, M.
1987-01-01
In this report the Nuclear Criticality Safety Analytical Methods Resource Center describes a new interactive version of CESAR, a critical experiments storage and retrieval program available on the Nuclear Criticality Information System (NCIS) database at Lawrence Livermore National Laboratory. The original version of CESAR did not include interactive search capabilities. The CESAR database was developed to provide a convenient, readily accessible means of storing and retrieving code input data for the SCALE Criticality Safety Analytical Sequences and the codes comprising those sequences. The database includes data for both cross section preparation and criticality safety calculations. 3 refs., 1 tab.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, P.B.; Yatabe, M.
1987-01-01
The Nuclear Criticality Safety Analytical Methods Resource Center announces the availability of a new interactive version of CESAR, a critical experiments storage and retrieval program available on the Nuclear Criticality Information System (NCIS) data base at Lawrence Livermore National Laboratory. The original version of CESAR did not include interactive search capabilities. The CESAR data base was developed to provide a convenient, readily accessible means of storing and retrieving code input data for the SCALE criticality safety analytical sequences and the codes comprising those sequences. The data base includes data for both cross-section preparation and criticality safety calculations.
Leva, M C; Cahill, J; Kay, A M; Losa, G; McDonald, N
2010-02-01
This paper presents the findings of research relating to the specification of a new human factors report, conducted as part of the work requirements for the Human Integration into the Lifecycle of Aviation Systems project, sponsored by the European Commission. Specifically, it describes the proposed concept for a unique report, which will form the basis for all operational and safety reports completed by flight crew. This includes all mandatory and optional reports. Critically, this form is central to the advancement of improved processes and technology tools, supporting airline performance management, safety management, organisational learning and knowledge integration/information-sharing activities. Specifically, this paper describes the background to the development of this reporting form, the logic and contents of this form and how reporting data will be made use of by airline personnel. This includes a description of the proposed intelligent planning process and the associated intelligent flight plan concept, which makes use of airline operational and safety analyses information. Primarily, this new reporting form has been developed in collaboration with a major Spanish airline. In addition, it has involved research with five other airlines. Overall, this has involved extensive field research, collaborative prototyping and evaluation of new reports/flight plan concepts and a number of evaluation activities. Participants have included both operational and management personnel, across different airline flight operations processes. Statement of Relevance: This paper presents the development of a reporting concept outlined through field research and collaborative prototyping within an airline. The resulting reporting function, embedded in the journey log compiled at the end of each flight, aims at enabling employees to audit the operations of the company they work for.
NASA Technical Reports Server (NTRS)
Neogi, Natasha A.
2016-01-01
There is a current drive towards enabling the deployment of increasingly autonomous systems in the National Airspace System (NAS). However, shifting the traditional roles and responsibilities between humans and automation for safety critical tasks must be managed carefully, otherwise the current emergent safety properties of the NAS may be disrupted. In this paper, a verification activity to assess the emergent safety properties of a clearly defined, safety critical, operational scenario that possesses tasks that can be fluidly allocated between human and automated agents is conducted. Task allocation role sets were proposed for a human-automation team performing a contingency maneuver in a reduced crew context. A safety critical contingency procedure (engine out on takeoff) was modeled in the Soar cognitive architecture, then translated into the Hybrid Input Output formalism. Verification activities were then performed to determine whether or not the safety properties held over the increasingly autonomous system. The verification activities lead to the development of several key insights regarding the implicit assumptions on agent capability. It subsequently illustrated the usefulness of task annotations associated with specialized requirements (e.g., communication, timing etc.), and demonstrated the feasibility of this approach.
Extended time-to-collision measures for road traffic safety assessment.
Minderhoud, M M; Bovy, P H
2001-01-01
This article describes two new safety indicators based on the time-to-collision notion suitable for comparative road traffic safety analyses. Such safety indicators can be applied in the comparison of a do-nothing case with an adapted situation, e.g. the introduction of intelligent driver support systems. In contrast to the classical time-to-collision value, measured at a cross section, the improved safety indicators use vehicle trajectories collected over a specific time horizon for a certain roadway segment to calculate the overall safety indicator value. Vehicle-specific indicator values as well as safety-critical probabilities can easily be determined from the developed safety measures. Application of the derived safety indicators is demonstrated for the assessment of the potential safety impacts of driver support systems from which it appears that some Autonomous Intelligent Cruise Control (AICC) designs are more safety-critical than the reference case without these systems. It is suggested that the indicator threshold value to be applied in the safety assessment has to be adapted when advanced AICC-systems with safe characteristics are introduced.
Supporting Upper-Level Undergraduate Students in Building a Systems Perspective in a Botany Course
ERIC Educational Resources Information Center
Zangori, Laura; Koontz, Jason A.
2017-01-01
Undergraduate biology majors require biological literacy about the critical and dynamic relationships between plants and ecosystems and the effect human-made processes have on these systems. To support students in understanding systems relationships, we redesigned an undergraduate botany course using an ecological framework and embedded systems…
Ginsburg, Liane R; Dhingra-Kumar, Neelam; Donaldson, Liam J
2017-06-15
The improvement of safety in healthcare worldwide depends in part on the knowledge, skills and attitudes of staff providing care. Greater patient safety content in health professional education and training programmes has been advocated internationally. While WHO Patient Safety Curriculum Guides (for Medical Schools and Multi-Professional Curricula) have been widely disseminated in low-income and middle-income countries (LMICs) over the last several years, little is known about patient safety curriculum implementation beyond high-income countries. The present study examines patient safety curriculum implementation in LMICs. Two cross-sectional surveys were carried out. First, 88 technical officers in Ministries of Health and WHO country offices were surveyed to identify the pattern of patient safety curricula at country level. A second survey followed that gathered information from 71 people in a position to provide institution-level perspectives on patient safety curriculum implementation. The majority, 69% (30/44), of the countries were either considering whether to implement a patient safety curriculum or actively planning, rather than actually implementing, or embedding one. Most organisations recognised the need for patient safety education and training and felt a safety curriculum was compatible with the values of their organisation; however, important faculty-level barriers to patient safety curriculum implementation were identified. Key structural markers, such as dedicated financial resources and relevant assessment tools to evaluate trainees' patient safety knowledge and skills, were in place in fewer than half of organisations studied. Greater attention to patient safety curriculum implementation is needed. The barriers to patient safety curriculum implementation we identified in LMICs are not unique to these regions. We propose a framework to act as a global standard for patient safety curriculum implementation. Educating leaders through the system in order to embed patient safety culture in education and clinical settings is a critical first step. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Non-functional Avionics Requirements
NASA Astrophysics Data System (ADS)
Paulitsch, Michael; Ruess, Harald; Sorea, Maria
Embedded systems in aerospace become more and more integrated in order to reduce weight, volume/size, and power of hardware for more fuel-effi ciency. Such integration tendencies change architectural approaches of system ar chi tec tures, which subsequently change non-functional requirements for plat forms. This paper provides some insight into state-of-the-practice of non-func tional requirements for developing ultra-critical embedded systems in the aero space industry, including recent changes and trends. In particular, formal requi re ment capture and formal analysis of non-functional requirements of avionic systems - including hard-real time, fault-tolerance, reliability, and per for mance - are exemplified by means of recent developments in SAL and HiLiTE.
System Guidelines for EMC Safety-Critical Circuits: Design, Selection, and Margin Demonstration
NASA Technical Reports Server (NTRS)
Lawton, R. M.
1996-01-01
Demonstration of safety margins for critical points (circuits) has traditionally been required since it first became a part of systems-level Electromagnetic Compatibility (EMC) requirements of MIL-E-6051C. The goal of this document is to present cost-effective guidelines for ensuring adequate Electromagnetic Effects (EME) safety margins on spacecraft critical circuits. It is for the use of NASA and other government agencies and their contractors to prevent loss of life, loss of spacecraft, or unacceptable degradation. This document provides practical definition and treatment guidance to contain costs within affordable limits.
Time Factor in the Theory of Anthropogenic Risk Prediction in Complex Dynamic Systems
NASA Astrophysics Data System (ADS)
Ostreikovsky, V. A.; Shevchenko, Ye N.; Yurkov, N. K.; Kochegarov, I. I.; Grishko, A. K.
2018-01-01
The article overviews the anthropogenic risk models that take into consideration the development of different factors in time that influence the complex system. Three classes of mathematical models have been analyzed for the use in assessing the anthropogenic risk of complex dynamic systems. These models take into consideration time factor in determining the prospect of safety change of critical systems. The originality of the study is in the analysis of five time postulates in the theory of anthropogenic risk and the safety of highly important objects. It has to be stressed that the given postulates are still rarely used in practical assessment of equipment service life of critically important systems. That is why, the results of study presented in the article can be used in safety engineering and analysis of critically important complex technical systems.
49 CFR 234.275 - Processor-based systems.
Code of Federal Regulations, 2011 CFR
2011-10-01
... new or novel technology, or which provide safety-critical data to a railroad signal or train control... requirements. New or novel technology refers to a technology not previously recognized for use as of March 7... but which provides safety-critical data to a signal or train control system shall be included in the...
49 CFR 234.275 - Processor-based systems.
Code of Federal Regulations, 2010 CFR
2010-10-01
... new or novel technology, or which provide safety-critical data to a railroad signal or train control... requirements. New or novel technology refers to a technology not previously recognized for use as of March 7... but which provides safety-critical data to a signal or train control system shall be included in the...
Quantitative safety assessment of air traffic control systems through system control capacity
NASA Astrophysics Data System (ADS)
Guo, Jingjing
Quantitative Safety Assessments (QSA) are essential to safety benefit verification and regulations of developmental changes in safety critical systems like the Air Traffic Control (ATC) systems. Effectiveness of the assessments is particularly desirable today in the safe implementations of revolutionary ATC overhauls like NextGen and SESAR. QSA of ATC systems are however challenged by system complexity and lack of accident data. Extending from the idea "safety is a control problem" in the literature, this research proposes to assess system safety from the control perspective, through quantifying a system's "control capacity". A system's safety performance correlates to this "control capacity" in the control of "safety critical processes". To examine this idea in QSA of the ATC systems, a Control-capacity Based Safety Assessment Framework (CBSAF) is developed which includes two control capacity metrics and a procedural method. The two metrics are Probabilistic System Control-capacity (PSC) and Temporal System Control-capacity (TSC); each addresses an aspect of a system's control capacity. And the procedural method consists three general stages: I) identification of safety critical processes, II) development of system control models and III) evaluation of system control capacity. The CBSAF was tested in two case studies. The first one assesses an en-route collision avoidance scenario and compares three hypothetical configurations. The CBSAF was able to capture the uncoordinated behavior between two means of control, as was observed in a historic midair collision accident. The second case study compares CBSAF with an existing risk based QSA method in assessing the safety benefits of introducing a runway incursion alert system. Similar conclusions are reached between the two methods, while the CBSAF has the advantage of simplicity and provides a new control-based perspective and interpretation to the assessments. The case studies are intended to investigate the potential and demonstrate the utilities of CBSAF and are not intended for thorough studies of collision avoidance and runway incursions safety, which are extremely challenging problems. Further development and thorough validations are required to allow CBSAF to reach implementation phases, e.g. addressing the issues of limited scalability and subjectivity.
FAILSAFE Health Management for Embedded Systems
NASA Technical Reports Server (NTRS)
Horvath, Gregory A.; Wagner, David A.; Wen, Hui Ying; Barry, Matthew
2010-01-01
The FAILSAFE project is developing concepts and prototype implementations for software health management in mission- critical, real-time embedded systems. The project unites features of the industry-standard ARINC 653 Avionics Application Software Standard Interface and JPL s Mission Data System (MDS) technology (see figure). The ARINC 653 standard establishes requirements for the services provided by partitioned, real-time operating systems. The MDS technology provides a state analysis method, canonical architecture, and software framework that facilitates the design and implementation of software-intensive complex systems. The MDS technology has been used to provide the health management function for an ARINC 653 application implementation. In particular, the focus is on showing how this combination enables reasoning about, and recovering from, application software problems.
SHINE Virtual Machine Model for In-flight Updates of Critical Mission Software
NASA Technical Reports Server (NTRS)
Plesea, Lucian
2008-01-01
This software is a new target for the Spacecraft Health Inference Engine (SHINE) knowledge base that compiles a knowledge base to a language called Tiny C - an interpreted version of C that can be embedded on flight processors. This new target allows portions of a running SHINE knowledge base to be updated on a "live" system without needing to halt and restart the containing SHINE application. This enhancement will directly provide this capability without the risk of software validation problems and can also enable complete integration of BEAM and SHINE into a single application. This innovation enables SHINE deployment in domains where autonomy is used during flight-critical applications that require updates. This capability eliminates the need for halting the application and performing potentially serious total system uploads before resuming the application with the loss of system integrity. This software enables additional applications at JPL (microsensors, embedded mission hardware) and increases the marketability of these applications outside of JPL.
System Guidelines for EMC Safety-Critical Circuits: Design, Selection, and Margin Demonstration
NASA Technical Reports Server (NTRS)
Lawton, R. M.
1996-01-01
Demonstration of required safety margins on critical electrical/electronic circuits in large complex systems has become an implementation and cost problem. These margins are the difference between the activation level of the circuit and the electrical noise on the circuit in the actual operating environment. This document discusses the origin of the requirement and gives a detailed process flow for the identification of the system electromagnetic compatibility (EMC) critical circuit list. The process flow discusses the roles of engineering disciplines such as systems engineering, safety, and EMC. Design and analysis guidelines are provided to assist the designer in assuring the system design has a high probability of meeting the margin requirements. Examples of approaches used on actual programs (Skylab and Space Shuttle Solid Rocket Booster) are provided to show how variations of the approach can be used successfully.
Quasi-Static Probabilistic Structural Analyses Process and Criteria
NASA Technical Reports Server (NTRS)
Goldberg, B.; Verderaime, V.
1999-01-01
Current deterministic structural methods are easily applied to substructures and components, and analysts have built great design insights and confidence in them over the years. However, deterministic methods cannot support systems risk analyses, and it was recently reported that deterministic treatment of statistical data is inconsistent with error propagation laws that can result in unevenly conservative structural predictions. Assuming non-nal distributions and using statistical data formats throughout prevailing stress deterministic processes lead to a safety factor in statistical format, which integrated into the safety index, provides a safety factor and first order reliability relationship. The embedded safety factor in the safety index expression allows a historically based risk to be determined and verified over a variety of quasi-static metallic substructures consistent with the traditional safety factor methods and NASA Std. 5001 criteria.
Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agamy, Mohammed
The “Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System” program is focused on developing innovative concepts for residential photovoltaic (PV) systems with the following objectives: to create an Innovative micro-inverter topology that reduces the cost from the best in class micro-inverter and provides high efficiency (>96% CEC - California Energy Commission), and 25+ year warranty, as well as reactive power support; integrate micro-inverter and PV module to reduce system price by at least $0.25/W through a) accentuating dual use of the module metal frame as a large area heat spreader reducing operating temperature, and b) eliminating redundant wiringmore » and connectors; and create micro-inverter controller handles smart grid and safety functions to simplify implementation and reduce cost.« less
Generalized implementation of software safety policies
NASA Technical Reports Server (NTRS)
Knight, John C.; Wika, Kevin G.
1994-01-01
As part of a research program in the engineering of software for safety-critical systems, we are performing two case studies. The first case study, which is well underway, is a safety-critical medical application. The second, which is just starting, is a digital control system for a nuclear research reactor. Our goal is to use these case studies to permit us to obtain a better understanding of the issues facing developers of safety-critical systems, and to provide a vehicle for the assessment of research ideas. The case studies are not based on the analysis of existing software development by others. Instead, we are attempting to create software for new and novel systems in a process that ultimately will involve all phases of the software lifecycle. In this abstract, we summarize our results to date in a small part of this project, namely the determination and classification of policies related to software safety that must be enforced to ensure safe operation. We hypothesize that this classification will permit a general approach to the implementation of a policy enforcement mechanism.
NASA Technical Reports Server (NTRS)
Swift, Gary M.; Allen, Gregory S.; Farmanesh, Farhad; George, Jeffrey; Petrick, David J.; Chayab, Fayez
2006-01-01
Shown in this presentation are recent results for the upset susceptibility of the various types of memory elements in the embedded PowerPC405 in the Xilinx V2P40 FPGA. For critical flight designs where configuration upsets are mitigated effectively through appropriate design triplication and configuration scrubbing, these upsets of processor elements can dominate the system error rate. Data from irradiations with both protons and heavy ions are given and compared using available models.
Some Challenges in the Design of Human-Automation Interaction for Safety-Critical Systems
NASA Technical Reports Server (NTRS)
Feary, Michael S.; Roth, Emilie
2014-01-01
Increasing amounts of automation are being introduced to safety-critical domains. While the introduction of automation has led to an overall increase in reliability and improved safety, it has also introduced a class of failure modes, and new challenges in risk assessment for the new systems, particularly in the assessment of rare events resulting from complex inter-related factors. Designing successful human-automation systems is challenging, and the challenges go beyond good interface development (e.g., Roth, Malin, & Schreckenghost 1997; Christoffersen & Woods, 2002). Human-automation design is particularly challenging when the underlying automation technology generates behavior that is difficult for the user to anticipate or understand. These challenges have been recognized in several safety-critical domains, and have resulted in increased efforts to develop training, procedures, regulations and guidance material (CAST, 2008, IAEA, 2001, FAA, 2013, ICAO, 2012). This paper points to the continuing need for new methods to describe and characterize the operational environment within which new automation concepts are being presented. We will describe challenges to the successful development and evaluation of human-automation systems in safety-critical domains, and describe some approaches that could be used to address these challenges. We will draw from experience with the aviation, spaceflight and nuclear power domains.
Visual warning system for worker safety on roadside work-zones.
DOT National Transportation Integrated Search
2016-08-01
Growing traffic on US roadways and heavy construction machinery on road construction sites pose a critical safety : threat to construction workers. This report summarizes the design and development of a worker safety system using : Dedicated Short Ra...
Aluminum Data Measurements and Evaluation for Criticality Safety Applications
NASA Astrophysics Data System (ADS)
Leal, L. C.; Guber, K. H.; Spencer, R. R.; Derrien, H.; Wright, R. Q.
2002-12-01
The Defense Nuclear Facility Safety Board (DNFSB) Recommendation 93-2 motivated the US Department of Energy (DOE) to develop a comprehensive criticality safety program to maintain and to predict the criticality of systems throughout the DOE complex. To implement the response to the DNFSB Recommendation 93-2, a Nuclear Criticality Safety Program (NCSP) was created including the following tasks: Critical Experiments, Criticality Benchmarks, Training, Analytical Methods, and Nuclear Data. The Nuclear Data portion of the NCSP consists of a variety of differential measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) at the Oak Ridge National Laboratory (ORNL), data analysis and evaluation using the generalized least-squares fitting code SAMMY in the resolved, unresolved, and high energy ranges, and the development and benchmark testing of complete evaluations for a nuclide for inclusion into the Evaluated Nuclear Data File (ENDF/B). This paper outlines the work performed at ORNL to measure, evaluate, and test the nuclear data for aluminum for applications in criticality safety problems.
Quality of life technology: the state of personal transportation.
van Roosmalen, Linda; Paquin, Gregory J; Steinfeld, Aaron M
2010-02-01
Motor vehicles are a technology that has been embedded in the built environment since the early 1900s. Personal transportation is important for the quality of life of individuals who have disabilities because it gives a feeling of freedom and enables individuals who have mobility impairments to participate in the community. This article describes the evaluation of individuals and their cognitive, sensory, and physical abilities that are important for (safe) driving. A case is made for independent mobility for individuals who have disabilities and elderly individuals by first giving an overview of the functional, cognitive, and sensory abilities that are critical for driving. Second, the types of vehicle modifications and state-of-the-art controls that are available and on the horizon are described and the way in which these technologies are selected to meet driver needs is explained. Requirements for driver safety systems for drivers who remain in their wheelchairs are then discussed. Finally, emerging and innovative driving enhancement systems, such as obstacle avoidance and navigation, are discussed, as are their benefits in helping drivers who have disabilities and elderly drivers to experience safe and independent driving.
Modelling safety of multistate systems with ageing components
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kołowrocki, Krzysztof; Soszyńska-Budny, Joanna
An innovative approach to safety analysis of multistate ageing systems is presented. Basic notions of the ageing multistate systems safety analysis are introduced. The system components and the system multistate safety functions are defined. The mean values and variances of the multistate systems lifetimes in the safety state subsets and the mean values of their lifetimes in the particular safety states are defined. The multi-state system risk function and the moment of exceeding by the system the critical safety state are introduced. Applications of the proposed multistate system safety models to the evaluation and prediction of the safty characteristics ofmore » the consecutive “m out of n: F” is presented as well.« less
Embedding technology into inter-professional best practices in home safety evaluation.
Burns, Suzanne Perea; Pickens, Noralyn Davel
2017-08-01
To explore inter-professional home evaluators' perspectives and needs for building useful and acceptable decision-support tools for the field of home modifications. Twenty semi-structured interviews were conducted with a range of home modification professionals from different regions of the United States. The interview transcripts were analyzed with a qualitative, descriptive, perspective approach. Technology supports current best practice and has potential to inform decision making through features that could enhance home evaluation processes, quality, efficiency and inter-professional communication. Technological advances with app design have created numerous opportunities for the field of home modifications. Integrating technology and inter-professional best practices will improve home safety evaluation and intervention development to meet client-centred and societal needs. Implications for rehabilitation Understanding home evaluators technology needs for home safety evaluations contributes to the development of app-based assessments. Integrating inter-professional perspectives of best practice and technological needs in an app for home assessments improves processes. Novice and expert home evaluators would benefit from decision support systems embedded in app-based assessments. Adoption of app-based assessment would improve efficiency while remaining client-centred.
Security for safety critical space borne systems
NASA Technical Reports Server (NTRS)
Legrand, Sue
1987-01-01
The Space Station contains safety critical computer software components in systems that can affect life and vital property. These components require a multilevel secure system that provides dynamic access control of the data and processes involved. A study is under way to define requirements for a security model providing access control through level B3 of the Orange Book. The model will be prototyped at NASA-Johnson Space Center.
Does the concept of safety culture help or hinder systems thinking in safety?
Reiman, Teemu; Rollenhagen, Carl
2014-07-01
The concept of safety culture has become established in safety management applications in all major safety-critical domains. The idea that safety culture somehow represents a "systemic view" on safety is seldom explicitly spoken out, but nevertheless seem to linger behind many safety culture discourses. However, in this paper we argue that the "new" contribution to safety management from safety culture never really became integrated with classical engineering principles and concepts. This integration would have been necessary for the development of a more genuine systems-oriented view on safety; e.g. a conception of safety in which human, technological, organisational and cultural factors are understood as mutually interacting elements. Without of this integration, researchers and the users of the various tools and methods associated with safety culture have sometimes fostered a belief that "safety culture" in fact represents such a systemic view about safety. This belief is, however, not backed up by theoretical or empirical evidence. It is true that safety culture, at least in some sense, represents a holistic term-a totality of factors that include human, organisational and technological aspects. However, the departure for such safety culture models is still human and organisational factors rather than technology (or safety) itself. The aim of this paper is to critically review the various uses of the concept of safety culture as representing a systemic view on safety. The article will take a look at the concepts of culture and safety culture based on previous studies, and outlines in more detail the theoretical challenges in safety culture as a systems concept. The paper also presents recommendations on how to make safety culture more systemic. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bakhri, S.; Sumarno, E.; Himawan, R.; Akbar, T. Y.; Subekti, M.; Sunaryo, G. R.
2018-02-01
Three research reactors owned by BATAN have been more than 25 years. Aging of (Structure, System and Component) SSC which is mainly related to mechanical causes become the most important issue for the sustainability and safety operation. Acoustic Emission (AE) is one of the appropriate and recommended methods by the IAEA for inspection as well as at the same time for the monitoring of mechanical SSC related. However, the advantages of AE method in detecting the acoustic emission both for the inspection and the online monitoring require a relatively complex measurement system including hardware software system for the signal detection and analysis purposes. Therefore, aim of this work was to develop an AE system based on an embedded system which capable for doing both the online monitoring and inspection of the research reactor’s integrity structure. An embedded system was selected due to the possibility to install the equipment on the field in extreme environmental condition with capability to store, analyses, and send the required information for further maintenance and operation. The research was done by designing the embedded system based on the Field Programmable Gate Array (FPGA) platform, because of their execution speed and system reconfigurable opportunities. The AE embedded system is then tested to identify the AE source location and AE characteristic under tensile material testing. The developed system successfully acquire the AE elastic waveform and determine the parameter-based analysis such as the amplitude, peak, duration, rise time, counts and the average frequency both for the source location test and the tensile test.
Copilot: Monitoring Embedded Systems
NASA Technical Reports Server (NTRS)
Pike, Lee; Wegmann, Nis; Niller, Sebastian; Goodloe, Alwyn
2012-01-01
Runtime verification (RV) is a natural fit for ultra-critical systems, where correctness is imperative. In ultra-critical systems, even if the software is fault-free, because of the inherent unreliability of commodity hardware and the adversity of operational environments, processing units (and their hosted software) are replicated, and fault-tolerant algorithms are used to compare the outputs. We investigate both software monitoring in distributed fault-tolerant systems, as well as implementing fault-tolerance mechanisms using RV techniques. We describe the Copilot language and compiler, specifically designed for generating monitors for distributed, hard real-time systems. We also describe two case-studies in which we generated Copilot monitors in avionics systems.
Evaluating real-time Java for mission-critical large-scale embedded systems
NASA Technical Reports Server (NTRS)
Sharp, D. C.; Pla, E.; Luecke, K. R.; Hassan, R. J.
2003-01-01
This paper describes benchmarking results on an RT JVM. This paper extends previously published results by including additional tests, by being run on a recently available pre-release version of the first commercially supported RTSJ implementation, and by assessing results based on our experience with avionics systems in other languages.
Verification and Implementation of Operations Safety Controls for Flight Missions
NASA Technical Reports Server (NTRS)
Smalls, James R.; Jones, Cheryl L.; Carrier, Alicia S.
2010-01-01
There are several engineering disciplines, such as reliability, supportability, quality assurance, human factors, risk management, safety, etc. Safety is an extremely important engineering specialty within NASA, and the consequence involving a loss of crew is considered a catastrophic event. Safety is not difficult to achieve when properly integrated at the beginning of each space systems project/start of mission planning. The key is to ensure proper handling of safety verification throughout each flight/mission phase. Today, Safety and Mission Assurance (S&MA) operations engineers continue to conduct these flight product reviews across all open flight products. As such, these reviews help ensure that each mission is accomplished with safety requirements along with controls heavily embedded in applicable flight products. Most importantly, the S&MA operations engineers are required to look for important design and operations controls so that safety is strictly adhered to as well as reflected in the final flight product.
USDA-ARS?s Scientific Manuscript database
Facing the increasing food safety issues, Chinese government has been carrying out compulsory tests on food to meet the requirements of domestic and foreign markets. Colloidal-gold test strips using the colorimetric principle are widely used for rapid qualitative detection of harmful residues in fo...
Software Dependability and Safety Evaluations ESA's Initiative
NASA Astrophysics Data System (ADS)
Hernek, M.
ESA has allocated funds for an initiative to evaluate Dependability and Safety methods of Software. The objectives of this initiative are; · More extensive validation of Safety and Dependability techniques for Software · Provide valuable results to improve the quality of the Software thus promoting the application of Dependability and Safety methods and techniques. ESA space systems are being developed according to defined PA requirement specifications. These requirements may be implemented through various design concepts, e.g. redundancy, diversity etc. varying from project to project. Analysis methods (FMECA. FTA, HA, etc) are frequently used during requirements analysis and design activities to assure the correct implementation of system PA requirements. The criticality level of failures, functions and systems is determined and by doing that the critical sub-systems are identified, on which dependability and safety techniques are to be applied during development. Proper performance of the software development requires the development of a technical specification for the products at the beginning of the life cycle. Such technical specification comprises both functional and non-functional requirements. These non-functional requirements address characteristics of the product such as quality, dependability, safety and maintainability. Software in space systems is more and more used in critical functions. Also the trend towards more frequent use of COTS and reusable components pose new difficulties in terms of assuring reliable and safe systems. Because of this, its dependability and safety must be carefully analysed. ESA identified and documented techniques, methods and procedures to ensure that software dependability and safety requirements are specified and taken into account during the design and development of a software system and to verify/validate that the implemented software systems comply with these requirements [R1].
Plutonium Finishing Plant (PFP) HVAC System Component Index
DOE Office of Scientific and Technical Information (OSTI.GOV)
DICK, J.D.
2000-02-28
The Plutonium Finishing Plant (PFP) WAC System includes sub-systems 25A through 25K. Specific system boundaries and justifications are contained in HNF-SD-CP-SDD-005, ''Definition and Means of Maintaining the Ventilation System Confinement Portion of the PFP Safety Envelope.'' The procurement requirements associated with the system necessitates procurement of some system equipment as Commercial Grade Items in accordance with HNF-PRO-268, ''Control of Purchased Items and Services.'' This document lists safety class and safety significant components for the Heating Ventilation Air Conditioning and specifies the critical characteristics for Commercial Grade Items, as required by HNF-PRO-268 and HNF-PRO-1819. These are the minimum specifications that themore » equipment must meet in order to properly perform its safety function. There may be several manufacturers or models that meet the critical characteristics for any one item.« less
Code of Federal Regulations, 2011 CFR
2011-10-01
... subsystem, system, or vessel to determine the least critical consequence. (b) All automatic control, remote control, safety control, and alarm systems must be failsafe. ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING VITAL SYSTEM AUTOMATION Reliability and Safety...
Planning the Unplanned Experiment: Assessing the Efficacy of Standards for Safety Critical Software
NASA Technical Reports Server (NTRS)
Graydon, Patrick J.; Holloway, C. Michael
2015-01-01
We need well-founded means of determining whether software is t for use in safety-critical applications. While software in industries such as aviation has an excellent safety record, the fact that software aws have contributed to deaths illustrates the need for justi ably high con dence in software. It is often argued that software is t for safety-critical use because it conforms to a standard for software in safety-critical systems. But little is known about whether such standards `work.' Reliance upon a standard without knowing whether it works is an experiment; without collecting data to assess the standard, this experiment is unplanned. This paper reports on a workshop intended to explore how standards could practicably be assessed. Planning the Unplanned Experiment: Assessing the Ecacy of Standards for Safety Critical Software (AESSCS) was held on 13 May 2014 in conjunction with the European Dependable Computing Conference (EDCC). We summarize and elaborate on the workshop's discussion of the topic, including both the presented positions and the dialogue that ensued.
2011 Annual Criticality Safety Program Performance Summary
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andrea Hoffman
The 2011 review of the INL Criticality Safety Program has determined that the program is robust and effective. The review was prepared for, and fulfills Contract Data Requirements List (CDRL) item H.20, 'Annual Criticality Safety Program performance summary that includes the status of assessments, issues, corrective actions, infractions, requirements management, training, and programmatic support.' This performance summary addresses the status of these important elements of the INL Criticality Safety Program. Assessments - Assessments in 2011 were planned and scheduled. The scheduled assessments included a Criticality Safety Program Effectiveness Review, Criticality Control Area Inspections, a Protection of Controlled Unclassified Information Inspection,more » an Assessment of Criticality Safety SQA, and this management assessment of the Criticality Safety Program. All of the assessments were completed with the exception of the 'Effectiveness Review' for SSPSF, which was delayed due to emerging work. Although minor issues were identified in the assessments, no issues or combination of issues indicated that the INL Criticality Safety Program was ineffective. The identification of issues demonstrates the importance of an assessment program to the overall health and effectiveness of the INL Criticality Safety Program. Issues and Corrective Actions - There are relatively few criticality safety related issues in the Laboratory ICAMS system. Most were identified by Criticality Safety Program assessments. No issues indicate ineffectiveness in the INL Criticality Safety Program. All of the issues are being worked and there are no imminent criticality concerns. Infractions - There was one criticality safety related violation in 2011. On January 18, 2011, it was discovered that a fuel plate bundle in the Nuclear Materials Inspection and Storage (NMIS) facility exceeded the fissionable mass limit, resulting in a technical safety requirement (TSR) violation. The TSR limits fuel plate bundles to 1085 grams U-235, which is the maximum loading of an ATR fuel element. The overloaded fuel plate bundle contained 1097 grams U-235 and was assembled under an 1100 gram U-235 limit in 1982. In 2003, the limit was reduced to 1085 grams citing a new criticality safety evaluation for ATR fuel elements. The fuel plate bundle inventories were not checked for compliance prior to implementing the reduced limit. A subsequent review of the NMIS inventory did not identify further violations. Requirements Management - The INL Criticality Safety program is organized and well documented. The source requirements for the INL Criticality Safety Program are from 10 CFR 830.204, DOE Order 420.1B, Chapter III, 'Nuclear Criticality Safety,' ANSI/ANS 8-series Industry Standards, and DOE Standards. These source requirements are documented in LRD-18001, 'INL Criticality Safety Program Requirements Manual.' The majority of the criticality safety source requirements are contained in DOE Order 420.1B because it invokes all of the ANSI/ANS 8-Series Standards. DOE Order 420.1B also invokes several DOE Standards, including DOE-STD-3007, 'Guidelines for Preparing Criticality Safety Evaluations at Department of Energy Non-Reactor Nuclear Facilities.' DOE Order 420.1B contains requirements for DOE 'Heads of Field Elements' to approve the criticality safety program and specific elements of the program, namely, the qualification of criticality staff and the method for preparing criticality safety evaluations. This was accomplished by the approval of SAR-400, 'INL Standardized Nuclear Safety Basis Manual,' Chapter 6, 'Prevention of Inadvertent Criticality.' Chapter 6 of SAR-400 contains sufficient detail and/or reference to the specific DOE and contractor documents that adequately describe the INL Criticality Safety Program per the elements specified in DOE Order 420.1B. The Safety Evaluation Report for SAR-400 specifically recognizes that the approval of SAR-400 approves the INL Criticality Safety Program. No new source requirements were released in 2011. A revision to LRD-18001 is planned for 2012 to clarify design requirements for criticality alarms. Training - Criticality Safety Engineering has developed training and provides training for many employee positions, including fissionable material handlers, facility managers, criticality safety officers, firefighters, and criticality safety engineers. Criticality safety training at the INL is a program strength. A revision to the training module developed in 2010 to supplement MFC certified fissionable material handlers (operators) training was prepared and presented in August of 2011. This training, 'Applied Science of Criticality Safety,' builds upon existing training and gives operators a better understanding of how their criticality controls are derived. Improvements to 00INL189, 'INL Criticality Safety Principles' are planned for 2012 to strengthen fissionable material handler training.« less
Embedding research to improve program implementation in Latin America and the Caribbean.
Tran, Nhan; Langlois, Etienne V; Reveiz, Ludovic; Varallyay, Ilona; Elias, Vanessa; Mancuso, Arielle; Becerra-Posada, Francisco; Ghaffar, Abdul
2017-06-08
In the last 10 years, implementation research has come to play a critical role in improving the implementation of already-proven health interventions by promoting the systematic uptake of research findings and other evidence-based strategies into routine practice. The Alliance for Health Policy and Systems Research and the Pan American Health Organization implemented a program of embedded implementation research to support health programs in Latin America and the Caribbean (LAC) in 2014-2015. A total of 234 applications were received from 28 countries in the Americas. The Improving Program Implementation through Embedded Research (iPIER) scheme supported 12 implementation research projects led by health program implementers from nine LAC countries: Argentina, Bolivia, Brazil, Chile, Colombia, Mexico, Panama, Peru, and Saint Lucia. Through this experience, we learned that the "insider" perspective, which implementers bring to the research proposal, is particularly important in identifying research questions that focus on the systems failures that often manifest in barriers to implementation. This paper documents the experience of and highlights key conclusions about the conduct of embedded implementation research. The iPIER experience has shown great promise for embedded research models that place implementers at the helm of implementation research initiatives.
The Space Station Freedom - International cooperation and innovation in space safety
NASA Technical Reports Server (NTRS)
Rodney, George A.
1989-01-01
The Space Station Freedom (SSF) being developed by the United States, European Space Agency (ESA), Japan, and Canada poses novel safety challenges in design, operations, logistics, and program management. A brief overview discloses many features that make SSF a radical departure from earlier low earth orbit (LEO) space stations relative to safety management: size and power levels; multiphase manned assembly; 30-year planned lifetime, with embedded 'hooks and scars' forevolution; crew size and skill-mix variability; sustained logistical dependence; use of man, robotics and telepresence for on-orbit maintenance of station and free-flyer systems; closed-environment recycling; use of automation and expert systems; long-term operation of collocated life-sciences and materials-science experiments, requiring control and segregation of hazardous and chemically incompatible materials; and materials aging in space.
Terahertz Computed Tomography of NASA Thermal Protection System Materials
NASA Technical Reports Server (NTRS)
Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.
2011-01-01
A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.
Cyber Security Threats to Safety-Critical, Space-Based Infrastructures
NASA Astrophysics Data System (ADS)
Johnson, C. W.; Atencia Yepez, A.
2012-01-01
Space-based systems play an important role within national critical infrastructures. They are being integrated into advanced air-traffic management applications, rail signalling systems, energy distribution software etc. Unfortunately, the end users of communications, location sensing and timing applications often fail to understand that these infrastructures are vulnerable to a wide range of security threats. The following pages focus on concerns associated with potential cyber-attacks. These are important because future attacks may invalidate many of the safety assumptions that support the provision of critical space-based services. These safety assumptions are based on standard forms of hazard analysis that ignore cyber-security considerations This is a significant limitation when, for instance, security attacks can simultaneously exploit multiple vulnerabilities in a manner that would never occur without a deliberate enemy seeking to damage space based systems and ground infrastructures. We address this concern through the development of a combined safety and security risk assessment methodology. The aim is to identify attack scenarios that justify the allocation of additional design resources so that safety barriers can be strengthened to increase our resilience against security threats.
Validation of Safety-Critical Systems for Aircraft Loss-of-Control Prevention and Recovery
NASA Technical Reports Server (NTRS)
Belcastro, Christine M.
2012-01-01
Validation of technologies developed for loss of control (LOC) prevention and recovery poses significant challenges. Aircraft LOC can result from a wide spectrum of hazards, often occurring in combination, which cannot be fully replicated during evaluation. Technologies developed for LOC prevention and recovery must therefore be effective under a wide variety of hazardous and uncertain conditions, and the validation framework must provide some measure of assurance that the new vehicle safety technologies do no harm (i.e., that they themselves do not introduce new safety risks). This paper summarizes a proposed validation framework for safety-critical systems, provides an overview of validation methods and tools developed by NASA to date within the Vehicle Systems Safety Project, and develops a preliminary set of test scenarios for the validation of technologies for LOC prevention and recovery
ERIC Educational Resources Information Center
Good, Jennifer; Bennett, Joan
2005-01-01
Teacher retention is a critical problem in public education (Ingersoll, 2002), demanding collaboration between universities and local public school systems. Using veteran teacher mentors employed in a public school system to facilitate ongoing monthly support groups, communities of beginning teachers were formed, embedded within the public schools…
Wireless microsensors for health monitoring of aircraft structures
NASA Astrophysics Data System (ADS)
Varadan, Vijay K.
2003-01-01
The integration of MEMS, IDTs (interdigital transducers) and required microelectronics and conformal antennas to realize programmable, robust and low cost passive microsensors suitable for many military structures and systems including aircraft, missiles and munitions is presented in this paper. The technology is currently being applied to the structural health monitoring of critical aircraft components. The approach integrates acoustic emission, strain gauges, MEMS accelerometers, gyroscopes and vibration monitoring devices with signal processing electronics to provide real-time indicators of incipient failure of aircraft components with a known history of catastrophic failure due to fracture. Recently a combination of the need for safety in the air and the desire to control costs is encouraging the use of in-flight monitoring of aircraft components and systems using light-weight, wireless and cost effective microsensors and MEMS. An in-situ Aircraft structural health monitoring (ASHM) system, with sensors embedded in the composite structure or surface-mounted on the structure, would permit the timely detection of damage in aircraft. Micromachining offers the potential for fabricating a range of microsensors and MEMS for structural applications including load, vibration and acoustics characterization and monitoring. Such microsensors are extremely small; they can be embedded into structural materials, can be mass-produced and are therefore potentially cheap. Additionally a range of sensor types can be integrated onto a single chip with built-in electronics and ASIC (Application Specific Integrated Circuit), providing a low power Microsystems. The smart sensors are being developed using the standard microelectronics and micromachining in conjunction with novel Penn State smart electronics or wireless communication systems suitable for condition monitoring of aircraft structures in-flight. A hybrid accelerometer and gyroscope in a single chip suitable for inertial navigation system and other microsensors for health monitoring and condition-based maintenance of structures, drag sensing and control of aircraft, strain and deflection of structures and systems, ice sensing on aircraft, remote temperature and humidity measurement of propellant in munitions, chemical sensing, etc. are discussed.
Issues in Software System Safety: Polly Ann Smith Co. versus Ned I. Ludd
NASA Technical Reports Server (NTRS)
Holloway, C. Michael
2002-01-01
This paper is a work of fiction, but it is fiction with a very real purpose: to stimulate careful thought and friendly discussion about some questions for which thought is often careless and discussion is often unfriendly. To accomplish this purpose, the paper creates a fictional legal case. The most important issue in this fictional case is whether certain proffered expert testimony about software engineering for safety critical systems should be admitted. Resolving this issue requires deciding the extent to which current practices and research in software engineering, especially for safety-critical systems, can rightly be considered based on knowledge, rather than opinion.
Richter, Lars; Bruder, Ralf
2013-05-01
Most medical robotic systems require direct interaction or contact with the robot. Force-Torque (FT) sensors can easily be mounted to the robot to control the contact pressure. However, evaluation is often done in software, which leads to latencies. To overcome that, we developed an independent safety system, named FTA sensor, which is based on an FT sensor and an accelerometer. An embedded system (ES) runs a real-time monitoring system for continuously checking of the readings. In case of a collision or error, it instantaneously stops the robot via the robot's external emergency stop. We found that the ES implementing the FTA sensor has a maximum latency of [Formula: see text] ms to trigger the robot's emergency stop. For the standard settings in the application of robotized transcranial magnetic stimulation, the robot will stop after at most 4 mm. Therefore, it works as an independent safety layer preventing patient and/or operator from serious harm.
SU-E-T-201: Safety-Focused Customization of Treatment Plan Documentation.
Schubert, L; Westerly, D; Stuhr, K; Miften, M
2012-06-01
Plan report documentation contains numerous details about the treatment plan, but critical information for patient safety is often presented without special emphasis. This can make it difficult to detect errors from treatment planning and data transfer during the initial chart review. The objective of this work is to improve safety measures in radiation therapy practice by customizing the treatment plan report to emphasize safety-critical information. Commands within the template file from a commercial planning system (Eclipse, Varian Medical Systems) that automatically generates the treatment plan report were reviewed and modified. Safety-critical plan parameters were identified from published risks known to be inherent in the treatment planning process. Risks having medium to high potential impact on patient safety included incorrect patient identifiers, erroneous use of the treatment prescription, and incorrect transfer of beam parameters or consideration of accessories. Specific examples of critical information in the treatment plan report that can be overlooked during a chart review included prescribed dose per fraction and number of fractions, wedge and open field monitor units, presence of beam accessories, and table shifts for patient setup. Critical information was streamlined and concentrated. Patient and plan identification, dose prescription details, and patient positioning couch shift instructions were placed on the first page. Plan information to verify the correct data transfer to the record and verify system was re-organized in an easy to review tabular format and placed in the second page of the customized printout. Placeholders were introduced to indicate both the presence and absence of beam modifiers. Font sizes and spacing were adjusted for clarity, and departmental standards and terminology were introduced to streamline data communication among staff members. Plan reporting documentation has been customized to concentrate and emphasize safety-critical information, which should allow for a more efficient, robust chart review process. © 2012 American Association of Physicists in Medicine.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ondrej Linda; Todd Vollmer; Jim Alves-Foss
2011-08-01
Resiliency and cyber security of modern critical infrastructures is becoming increasingly important with the growing number of threats in the cyber-environment. This paper proposes an extension to a previously developed fuzzy logic based anomaly detection network security cyber sensor via incorporating Type-2 Fuzzy Logic (T2 FL). In general, fuzzy logic provides a framework for system modeling in linguistic form capable of coping with imprecise and vague meanings of words. T2 FL is an extension of Type-1 FL which proved to be successful in modeling and minimizing the effects of various kinds of dynamic uncertainties. In this paper, T2 FL providesmore » a basis for robust anomaly detection and cyber security state awareness. In addition, the proposed algorithm was specifically developed to comply with the constrained computational requirements of low-cost embedded network security cyber sensors. The performance of the system was evaluated on a set of network data recorded from an experimental cyber-security test-bed.« less
Wirtz, Sebastian F; Cunha, Adauto P A; Labusch, Marc; Marzun, Galina; Barcikowski, Stephan; Söffker, Dirk
2018-06-01
Today, the demand for continuous monitoring of valuable or safety critical equipment is increasing in many industrial applications due to safety and economical requirements. Therefore, reliable in-situ measurement techniques are required for instance in Structural Health Monitoring (SHM) as well as process monitoring and control. Here, current challenges are related to the processing of sensor data with a high data rate and low latency. In particular, measurement and analyses of Acoustic Emission (AE) are widely used for passive, in-situ inspection. Advantages of AE are related to its sensitivity to different micro-mechanical mechanisms on the material level. However, online processing of AE waveforms is computationally demanding. The related equipment is typically bulky, expensive, and not well suited for permanent installation. The contribution of this paper is the development of a Field Programmable Gate Array (FPGA)-based measurement system using ZedBoard devlopment kit with Zynq-7000 system on chip for embedded implementation of suitable online processing algorithms. This platform comprises a dual-core Advanced Reduced Instruction Set Computer Machine (ARM) architecture running a Linux operating system and FPGA fabric. A FPGA-based hardware implementation of the discrete wavelet transform is realized to accelerate processing the AE measurements. Key features of the system are low cost, small form factor, and low energy consumption, which makes it suitable to serve as field-deployed measurement and control device. For verification of the functionality, a novel automatically realized adjustment of the working distance during pulsed laser ablation in liquids is established as an example. A sample rate of 5 MHz is achieved at 16 bit resolution.
Secure real-time wireless video streaming in the aeronautical telecommunications network
NASA Astrophysics Data System (ADS)
Czernik, Pawel; Olszyna, Jakub
2010-09-01
As Air Traffic Control Systems move from a voice only environment to one in which clearances are issued via data link, there is a risk that an unauthorized entity may attempt to masquerade as either the pilot or controller. In order to protect against this and related attacks, air-ground communications must be secured. The challenge is to add security in an environment in which bandwidth is limited. The Aeronautical Telecommunications Network (ATN) is an enabling digital network communications technology that addresses capacity and efficiency issues associated with current aeronautical voice communication systems. Equally important, the ATN facilitates migration to free flight, where direct computer-to-computer communication will automate air traffic management, minimize controller and pilot workload, and improve overall aircraft routing efficiency. Protecting ATN communications is critical since safety-of-flight is seriously affected if an unauthorized entity, a hacker for example, is able to penetrate an otherwise reliable communications system and accidentally or maliciously introduce erroneous information that jeopardizes the overall safety and integrity of a given airspace. However, an ATN security implementation must address the challenges associated with aircraft mobility, limited bandwidth communication channels, and uninterrupted operation across organizational and geopolitical boundaries. This paper provides a brief overview of the ATN, the ATN security concept, and begins a basic introduction to the relevant security concepts of security threats, security services and security mechanisms. Security mechanisms are further examined by presenting the fundamental building blocks of symmetric encipherment, asymmetric encipherment, and hash functions. The second part of this paper presents the project of cryptographiclly secure wireless communication between Unmanned Aerial Vehicles (UAV) and the ground station in the ATM system, based on the ARM9 processor development kid and Embedded Linux operation system.
Pediatric post-marketing safety systems in North America: assessment of the current status.
McMahon, Ann W; Wharton, Gerold T; Bonnel, Renan; DeCelle, Mary; Swank, Kimberley; Testoni, Daniela; Cope, Judith U; Smith, Phillip Brian; Wu, Eileen; Murphy, Mary Dianne
2015-08-01
It is critical to have pediatric post-marketing safety systems that contain enough clinical and epidemiological detail to draw regulatory, public health, and clinical conclusions. The pediatric safety surveillance workshop (PSSW), coordinated by the Food and Drug Administration (FDA), identified these pediatric systems as of 2010. This manuscript aims to update the information from the PSSW and look critically at the systems currently in use. We reviewed North American pediatric post-marketing safety systems such as databases, networks, and research consortiums found in peer-reviewed journals and other online sources. We detail clinical examples from three systems that FDA used to assess pediatric medical product safety. Of the 59 systems reviewed for pediatric content, only nine were pediatric-focused and met the inclusion criteria. Brief descriptions are provided for these nine. The strengths and weaknesses of three systems (two of the nine pediatric-focused and one including both children and adults) are illustrated with clinical examples. Systems reviewed in this manuscript have strengths such as clinical detail, a large enough sample size to capture rare adverse events, and/or a patient denominator internal to the database. Few systems include all of these attributes. Pediatric drug safety would be better informed by utilizing multiple systems to take advantage of their individual characteristics. Copyright © 2015 John Wiley & Sons, Ltd.
Jerky driving--An indicator of accident proneness?
Bagdadi, Omar; Várhelyi, András
2011-07-01
This study uses continuously logged driving data from 166 private cars to derive the level of jerks caused by the drivers during everyday driving. The number of critical jerks found in the data is analysed and compared with the self-reported accident involvement of the drivers. The results show that the expected number of accidents for a driver increases with the number of critical jerks caused by the driver. Jerk analyses make it possible to identify safety critical driving behaviour or "accident prone" drivers. They also facilitate the development of safety measures such as active safety systems or advanced driver assistance systems, ADAS, which could be adapted for specific groups of drivers or specific risky driving behaviour. Copyright © 2011 Elsevier Ltd. All rights reserved.
Safety Analysis of Soybean Processing for Advanced Life Support
NASA Technical Reports Server (NTRS)
Hentges, Dawn L.
1999-01-01
Soybeans (cv. Hoyt) is one of the crops planned for food production within the Advanced Life Support System Integration Testbed (ALSSIT), a proposed habitat simulation for long duration lunar/Mars missions. Soybeans may be processed into a variety of food products, including soymilk, tofu, and tempeh. Due to the closed environmental system and importance of crew health maintenance, food safety is a primary concern on long duration space missions. Identification of the food safety hazards and critical control points associated with the closed ALSSIT system is essential for the development of safe food processing techniques and equipment. A Hazard Analysis Critical Control Point (HACCP) model was developed to reflect proposed production and processing protocols for ALSSIT soybeans. Soybean processing was placed in the type III risk category. During the processing of ALSSIT-grown soybeans, critical control points were identified to control microbiological hazards, particularly mycotoxins, and chemical hazards from antinutrients. Critical limits were suggested at each CCP. Food safety recommendations regarding the hazards and risks associated with growing, harvesting, and processing soybeans; biomass management; and use of multifunctional equipment were made in consideration of the limitations and restraints of the closed ALSSIT.
NASA Technical Reports Server (NTRS)
Gwaltney, David A.; Briscoe, Jeri M.
2005-01-01
Integrated System Health Management (ISHM) architectures for spacecraft will include hard real-time, critical subsystems and soft real-time monitoring subsystems. Interaction between these subsystems will be necessary and an architecture supporting multiple criticality levels will be required. Demonstration hardware for the Integrated Safety-Critical Advanced Avionics Communication & Control (ISAACC) system has been developed at NASA Marshall Space Flight Center. It is a modular system using a commercially available time-triggered protocol, ?Tp/C, that supports hard real-time distributed control systems independent of the data transmission medium. The protocol is implemented in hardware and provides guaranteed low-latency messaging with inherent fault-tolerance and fault-containment. Interoperability between modules and systems of modules using the TTP/C is guaranteed through definition of messages and the precise message schedule implemented by the master-less Time Division Multiple Access (TDMA) communications protocol. "Plug-and-play" capability for sensors and actuators provides automatically configurable modules supporting sensor recalibration and control algorithm re-tuning without software modification. Modular components of controlled physical system(s) critical to control algorithm tuning, such as pumps or valve components in an engine, can be replaced or upgraded as "plug and play" components without modification to the ISAACC module hardware or software. ISAACC modules can communicate with other vehicle subsystems through time-triggered protocols or other communications protocols implemented over Ethernet, MIL-STD- 1553 and RS-485/422. Other communication bus physical layers and protocols can be included as required. In this way, the ISAACC modules can be part of a system-of-systems in a vehicle with multi-tier subsystems of varying criticality. The goal of the ISAACC architecture development is control and monitoring of safety critical systems of a manned spacecraft. These systems include spacecraft navigation and attitude control, propulsion, automated docking, vehicle health management and life support. ISAACC can integrate local critical subsystem health management with subsystems performing long term health monitoring. The ISAACC system and its relationship to ISHM will be presented.
A Process-Centered Tool for Evaluating Patient Safety Performance and Guiding Strategic Improvement
2005-01-01
next patient safety steps in individual health care organizations. The low priority given to Category 3 (Focus on patients , other customers , and...presents a patient safety applicator tool for implementing and assessing patient safety systems in health care institutions. The applicator tool consists...the survey rounds. The study addressed three research questions: 1. What critical processes should be included in health care patient safety systems
14 CFR 417.123 - Computing systems and software.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Computing systems and software. 417.123... systems and software. (a) A launch operator must document a system safety process that identifies the... systems and software. (b) A launch operator must identify all safety-critical functions associated with...
14 CFR 417.123 - Computing systems and software.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Computing systems and software. 417.123... systems and software. (a) A launch operator must document a system safety process that identifies the... systems and software. (b) A launch operator must identify all safety-critical functions associated with...
14 CFR 417.123 - Computing systems and software.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Computing systems and software. 417.123... systems and software. (a) A launch operator must document a system safety process that identifies the... systems and software. (b) A launch operator must identify all safety-critical functions associated with...
14 CFR 417.123 - Computing systems and software.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Computing systems and software. 417.123... systems and software. (a) A launch operator must document a system safety process that identifies the... systems and software. (b) A launch operator must identify all safety-critical functions associated with...
14 CFR 417.123 - Computing systems and software.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Computing systems and software. 417.123... systems and software. (a) A launch operator must document a system safety process that identifies the... systems and software. (b) A launch operator must identify all safety-critical functions associated with...
Automated Pedestrian Detection, Count and Analysis System
DOT National Transportation Integrated Search
2015-04-15
Pedestrian and bicycle count data is necessary for transportation planning, implementing safety countermeasures, and traffic management. This data is critical when evaluating the pedestrian level of service of safety (LOSS) and pedestrian safety perf...
Human factors systems approach to healthcare quality and patient safety
Carayon, Pascale; Wetterneck, Tosha B.; Rivera-Rodriguez, A. Joy; Hundt, Ann Schoofs; Hoonakker, Peter; Holden, Richard; Gurses, Ayse P.
2013-01-01
Human factors systems approaches are critical for improving healthcare quality and patient safety. The SEIPS (Systems Engineering Initiative for Patient Safety) model of work system and patient safety is a human factors systems approach that has been successfully applied in healthcare research and practice. Several research and practical applications of the SEIPS model are described. Important implications of the SEIPS model for healthcare system and process redesign are highlighted. Principles for redesigning healthcare systems using the SEIPS model are described. Balancing the work system and encouraging the active and adaptive role of workers are key principles for improving healthcare quality and patient safety. PMID:23845724
Assessing drivers' response during automated driver support system failures with non-driving tasks.
Shen, Sijun; Neyens, David M
2017-06-01
With the increase in automated driver support systems, drivers are shifting from operating their vehicles to supervising their automation. As a result, it is important to understand how drivers interact with these automated systems and evaluate their effect on driver responses to safety critical events. This study aimed to identify how drivers responded when experiencing a safety critical event in automated vehicles while also engaged in non-driving tasks. In total 48 participants were included in this driving simulator study with two levels of automated driving: (a) driving with no automation and (b) driving with adaptive cruise control (ACC) and lane keeping (LK) systems engaged; and also two levels of a non-driving task (a) watching a movie or (b) no non-driving task. In addition to driving performance measures, non-driving task performance and the mean glance duration for the non-driving task were compared between the two levels of automated driving. Drivers using the automated systems responded worse than those manually driving in terms of reaction time, lane departure duration, and maximum steering wheel angle to an induced lane departure event. These results also found that non-driving tasks further impaired driver responses to a safety critical event in the automated system condition. In the automated driving condition, driver responses to the safety critical events were slower, especially when engaged in a non-driving task. Traditional driver performance variables may not necessarily effectively and accurately evaluate driver responses to events when supervising autonomous vehicle systems. Thus, it is important to develop and use appropriate variables to quantify drivers' performance under these conditions. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.
E-precision agriculture for small scale cash crops in Tobasa regency
NASA Astrophysics Data System (ADS)
Putra Simanjuntak, Panca; Tiurniari Napitupulu, Pangeran; Pratama Silalahi, Soni; Kisno; Pasaribu, Norlina; Valešová, Libuše
2017-09-01
Cash crop is a promising sector in Tobasa regency; however, the trend showed a negative change of the cash crop production in. This research aims to develop an application which is based on Arduino for watering and fertilizing corn land. The result of using e-precision agriculture based on embedded system is 100% higher than the conventional one and the risk of harvesting failure using the embedded system decreased to 50%. Embedded system in this study acquired critical environment measurements which at last affected the yield raising and risk reduction. As the result, the use of e-precision agriculture provided a framework to be used by different stakeholders to implement e-agriculture platform that supports marketing of agricultural production since the system is proven to save the material and time which finally reduces the risk of harvesting failure and increases the yield. In other words, the system is able to economize the use of water and fertilizer on a small corn land. The system will be developed for more efficiency in material loss and the mobile-based application development to reach sustainable rural development particularly for cash-crop farmers.
Embedding Context in Teaching Engineering Design
ERIC Educational Resources Information Center
Neumeyer, Xaver; Chen, Wei; McKenna, Ann F.
2013-01-01
Understanding the global, societal, environmental and economic (GSEE) context of a product, process or system is critical to an engineer's ability to design and innovate. The already packed curricula in engineering programs provide few occasions to offer meaningful experiences to address this issue, and most departments delegate this requirement…
Nursing leadership competencies: low-fidelity simulation as a teaching strategy.
Pollard, Cheryl L; Wild, Carol
2014-11-01
Nurses must demonstrate leadership and followership competencies within complex adaptive team environments to ensure patient and staff safety, effective use of resources, and an adaptive health care system. These competencies are demonstrated through the use of communication strategies that are embedded within a relational practice. Health care professionals, regardless of formal position, need to assert their opinions and perspectives using a communication style that demonstrates value of all team members in open discussions about quality patient care, appropriate access, and stewardship. Challenges to effective communication and relational practice are the individual and organizational patterns of behavior, and the subsequent impact that these behaviors have on others. Students articulate situational awareness when they conduct a critical analysis of individual, team, and organizational functioning, and then use this information and evidence gained from a critical literature review to develop recommendations to improve individual, team, and/or organizational performance. Leadership and followership simulation exercises, inclusive of public feedback and debriefing, are used as a pedagogical/andragogical strategy in a nursing baccalaureate senior leadership course to facilitate learning of team communication skills and improve situational awareness. We view this strategy as an alternative to traditional classroom learning activities which provide little opportunity for recursive learning. Copyright © 2014 Elsevier Ltd. All rights reserved.
The European space suit, a design for productivity and crew safety.
Skoog, A I; Berthier, S; Ollivier, Y
1991-01-01
In order to fulfill the two major mission objectives, i.e. support planned and unplanned external servicing of the COLUMBUS FFL and support the HERMES vehicle for safety critical operations and emergencies, the European Space Suit System baseline configuration incorporates a number of design features, which shall enhance the productivity and the crew safety of EVA astronauts. The work in EVA is today--and will be for several years--a manual work. Consequently, to improve productivity, the first challenge is to design a suit enclosure which minimizes movement restrictions and crew fatigue. It is covered by the "ergonomic" aspect of the suit design. Furthermore, it is also necessary to help the EVA crewmember in his work, by giving him the right information at the right time. Many solutions exist in this field of Man-Machine Interface, from a very simple system, based on cuff check lists, up to advanced systems, including Head-Up Displays. The design concept for improved productivity encompasses following features: easy donning/doffing thru rear entry, suit ergonomy optimisation, display of operational information in alpha-numerical and graphical form, and voice processing for operations and safety critical information. Concerning crew safety the major design features are: a lower R-factor for emergency EVA operations thru increased suit pressure, zero prebreath conditions for normal operations, visual and voice processing of all safety critical functions, and an autonomous life support system to permit unrestricted operations around HERMES and the CFFL. The paper analyses crew safety and productivity criteria and describes how these features are being built into the design of the European Space Suit System.
Product-based Safety Certification for Medical Devices Embedded Software.
Neto, José Augusto; Figueiredo Damásio, Jemerson; Monthaler, Paul; Morais, Misael
2015-01-01
Worldwide medical device embedded software certification practices are currently focused on manufacturing best practices. In Brazil, the national regulatory agency does not hold a local certification process for software-intensive medical devices and admits international certification (e.g. FDA and CE) from local and international industry to operate in the Brazilian health care market. We present here a product-based certification process as a candidate process to support the Brazilian regulatory agency ANVISA in medical device software regulation. Center of Strategic Technology for Healthcare (NUTES) medical device embedded software certification is based on a solid safety quality model and has been tested with reasonable success against the Class I risk device Generic Infusion Pump (GIP).
PFP Public Automatic Exchange (PAX) Commercial Grade Item (CGI) Critical Characteristics
DOE Office of Scientific and Technical Information (OSTI.GOV)
WHITE, W.F.
2000-04-04
This document specifies the critical characteristics for Commercial Grade Items (CGI) procured for use within the safety envelope of PFP's PAX system as required by HNF-PRO-268 and HNF-PRO-1819. These are the minimum specifications that the equipment must meet in order to properly perform its safety function. There may be several manufacturers or models that meet the critical characteristics for any one item.
NASA Technical Reports Server (NTRS)
Goodin, James Ronald
2006-01-01
NASA's Columbia Accident Investigation Board (CAIB) referred 8 times to the NASA "Silent Safety Program." This term, "Silent Safety Program" was not an original observation but first appeared in the Rogers Commission's Investigation of the Challenger Mishap. The CAIB on page 183 of its report in the paragraph titled 'Encouraging Minority Opinion,' stated "The Naval Reactor Program encourages minority opinions and "bad news." Leaders continually emphasize that when no minority opinions are present, the responsibility for a thorough and critical examination falls to management. . . Board interviews revealed that it is difficult for minority and dissenting opinions to percolate up through the agency's hierarchy. . ." The first question and perhaps the only question is - what is a silent safety program? Well, a silent safety program may be the same as the dog that didn't bark in Sherlock Holmes' "Adventure of the Silver Blaze" because system safety should behave as a devil's advocate for the program barking on every occasion to insure a critical review inclusion. This paper evaluates the NASA safety program and provides suggestions to prevent the recurrence of the silent safety program alluded to in the Challenger Mishap Investigation. Specifically targeted in the CAM report, "The checks and balances the safety system was meant to provide were not working." A silent system safety program is not unique to NASA but could emerge in any and every organization. Principles developed by Irving Janis in his book, Groupthink, listed criteria used to evaluate an organization's cultural attributes that allows a silent safety program to evolve. If evidence validates Jams's criteria, then Jams's recommendations for preventing groupthink can also be used to improve a critical evaluation and thus prevent the development of a silent safety program.
An aspect-oriented approach for designing safety-critical systems
NASA Astrophysics Data System (ADS)
Petrov, Z.; Zaykov, P. G.; Cardoso, J. P.; Coutinho, J. G. F.; Diniz, P. C.; Luk, W.
The development of avionics systems is typically a tedious and cumbersome process. In addition to the required functions, developers must consider various and often conflicting non-functional requirements such as safety, performance, and energy efficiency. Certainly, an integrated approach with a seamless design flow that is capable of requirements modelling and supporting refinement down to an actual implementation in a traceable way, may lead to a significant acceleration of development cycles. This paper presents an aspect-oriented approach supported by a tool chain that deals with functional and non-functional requirements in an integrated manner. It also discusses how the approach can be applied to development of safety-critical systems and provides experimental results.
Non-standard analysis and embedded software
NASA Technical Reports Server (NTRS)
Platek, Richard
1995-01-01
One model for computing in the future is ubiquitous, embedded computational devices analogous to embedded electrical motors. Many of these computers will control physical objects and processes. Such hidden computerized environments introduce new safety and correctness concerns whose treatment go beyond present Formal Methods. In particular, one has to begin to speak about Real Space software in analogy with Real Time software. By this we mean, computerized systems which have to meet requirements expressed in the real geometry of space. How to translate such requirements into ordinary software specifications and how to carry out proofs is a major challenge. In this talk we propose a research program based on the use of no-standard analysis. Much detail remains to be carried out. The purpose of the talk is to inform the Formal Methods community that Non-Standard Analysis provides a possible avenue to attack which we believe will be fruitful.
Hoshiba, Kotaro; Washizaki, Kai; Wakabayashi, Mizuho; Ishiki, Takahiro; Bando, Yoshiaki; Gabriel, Daniel; Nakadai, Kazuhiro; Okuno, Hiroshi G.
2017-01-01
In search and rescue activities, unmanned aerial vehicles (UAV) should exploit sound information to compensate for poor visual information. This paper describes the design and implementation of a UAV-embedded microphone array system for sound source localization in outdoor environments. Four critical development problems included water-resistance of the microphone array, efficiency in assembling, reliability of wireless communication, and sufficiency of visualization tools for operators. To solve these problems, we developed a spherical microphone array system (SMAS) consisting of a microphone array, a stable wireless network communication system, and intuitive visualization tools. The performance of SMAS was evaluated with simulated data and a demonstration in the field. Results confirmed that the SMAS provides highly accurate localization, water resistance, prompt assembly, stable wireless communication, and intuitive information for observers and operators. PMID:29099790
Hoshiba, Kotaro; Washizaki, Kai; Wakabayashi, Mizuho; Ishiki, Takahiro; Kumon, Makoto; Bando, Yoshiaki; Gabriel, Daniel; Nakadai, Kazuhiro; Okuno, Hiroshi G
2017-11-03
In search and rescue activities, unmanned aerial vehicles (UAV) should exploit sound information to compensate for poor visual information. This paper describes the design and implementation of a UAV-embedded microphone array system for sound source localization in outdoor environments. Four critical development problems included water-resistance of the microphone array, efficiency in assembling, reliability of wireless communication, and sufficiency of visualization tools for operators. To solve these problems, we developed a spherical microphone array system (SMAS) consisting of a microphone array, a stable wireless network communication system, and intuitive visualization tools. The performance of SMAS was evaluated with simulated data and a demonstration in the field. Results confirmed that the SMAS provides highly accurate localization, water resistance, prompt assembly, stable wireless communication, and intuitive information for observers and operators.
Automotive Airbag Safety Enhancement Final Report CRADA No. TSB-1165-95
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cutting, Jack; Durrell, Robert
The Vehicle Safety systems (VSS) Division of Quantic Industries, Inc. (QII) manufactured automotive airbag components. When both the driver and the passenger side airbags inflated in a tightly sealed passenger compartment, the compression of the surrounding air could and, in some instances, would cause damage to the eardrums of the occupants. The Aerospace and Division (ADD) of QII had partially developed the technology to fracture the canopy of a jet aircraft at the time of pilot ejection. The technical problem was how to adapt the canopy fracturing technology to the rear window of a motor vehicle in a safe andmore » cost effective manner. The existing approach was to replace the embedded rear window defroster with a series-parallel network of exploding bridge wires (EBWs). This would still provide the defrost function at low voltage/ current, but would cause fracturing of the window when a high current/voltage pulse was applied without pyrotechnics or explosives. The elements of this system were the embedded EBW network and a trunk-mounted fireset. The fireset would store the required energy to fire the network upon the receipt of a trigger signal from the existing air bag crash sensor.« less
ERIC Educational Resources Information Center
American School Board Journal, 1964
1964-01-01
Several aspects of school safety and protection are presented for school administrators and architects. Among those topics discussed are--(1) life safety, (2) vandalism controlled through proper design, (3) personal protective devices, and (4) fire alarm systems. Another critical factor in providing a complete school safety program is proper…
Winkelman, Warren J; Leonard, Kevin J
2004-01-01
There are constraints embedded in medical record structure that limit use by patients in self-directed disease management. Through systematic review of the literature from a critical perspective, four characteristics that either enhance or mitigate the influence of medical record structure on patient utilization of an electronic patient record (EPR) system have been identified: environmental pressures, physician centeredness, collaborative organizational culture, and patient centeredness. An evaluation framework is proposed for use when considering adaptation of existing EPR systems for online patient access. Exemplars of patient-accessible EPR systems from the literature are evaluated utilizing the framework. From this study, it appears that traditional information system research and development methods may not wholly capture many pertinent social issues that arise when expanding access of EPR systems to patients. Critically rooted methods such as action research can directly inform development strategies so that these systems may positively influence health outcomes.
Flexible Audit Trailing in Interactive Courseware.
ERIC Educational Resources Information Center
Judd, Terry; Kennedy, Gregor
This paper reports on the development and implementation of a flexible audit trail system comprising a library of auditing functions that can be embedded into interactive courseware and customized to the requirements of researchers and developers. A series of essential criteria considered critical to the development of a robust, flexible audit…
[Preliminary studies on critical control point of traceability system in wolfberry].
Liu, Sai; Xu, Chang-Qing; Li, Jian-Ling; Lin, Chen; Xu, Rong; Qiao, Hai-Li; Guo, Kun; Chen, Jun
2016-07-01
As a traditional Chinese medicine, wolfberry (Lycium barbarum) has a long cultivation history and a good industrial development foundation. With the development of wolfberry production, the expansion of cultivation area and the increased attention of governments and consumers on food safety, the quality and safety requirement of wolfberry is higher demanded. The quality tracing and traceability system of production entire processes is the important technology tools to protect the wolfberry safety, and to maintain sustained and healthy development of the wolfberry industry. Thus, this article analyzed the wolfberry quality management from the actual situation, the safety hazard sources were discussed according to the HACCP (hazard analysis and critical control point) and GAP (good agricultural practice for Chinese crude drugs), and to provide a reference for the traceability system of wolfberry. Copyright© by the Chinese Pharmaceutical Association.
Rimmed and edge thickened Stodola shaped flywheel
Kulkarni, S.V.; Stone, R.G.
1983-10-11
A flywheel is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel has a body composed of essentially planar isotropic high strength material. The flywheel body is enclosed by a rim of circumferentially wound fiber embedded in resin. The rim promotes flywheel safety and survivability. The flywheel has a truncated and edge thickened Stodola shape designed to optimize system mass and energy storage capability. 6 figs.
Rimmed and edge thickened stodola shaped flywheel. [Patent application
Kulkarni, S.V.; Stone, R.G.
1980-09-24
A flywheel is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel has a body composed of essentially planar isotropic high strength material. The flywheel body is enclosed by a rim of circumferentially wound fiber embedded in resin. The rim promotes flywheel safety and survivability. The flywheel has a truncated and edge thickened Stodola shape designed to optimize system mass and energy storage capability.
Safe and Efficient Support for Embeded Multi-Processors in ADA
NASA Astrophysics Data System (ADS)
Ruiz, Jose F.
2010-08-01
New software demands increasing processing power, and multi-processor platforms are spreading as the answer to achieve the required performance. Embedded real-time systems are also subject to this trend, but in the case of real-time mission-critical systems, the properties of reliability, predictability and analyzability are also paramount. The Ada 2005 language defined a subset of its tasking model, the Ravenscar profile, that provides the basis for the implementation of deterministic and time analyzable applications on top of a streamlined run-time system. This Ravenscar tasking profile, originally designed for single processors, has proven remarkably useful for modelling verifiable real-time single-processor systems. This paper proposes a simple extension to the Ravenscar profile to support multi-processor systems using a fully partitioned approach. The implementation of this scheme is simple, and it can be used to develop applications amenable to schedulability analysis.
NASA's Software Safety Standard
NASA Technical Reports Server (NTRS)
Ramsay, Christopher M.
2005-01-01
NASA (National Aeronautics and Space Administration) relies more and more on software to control, monitor, and verify its safety critical systems, facilities and operations. Since the 1960's there has hardly been a spacecraft (manned or unmanned) launched that did not have a computer on board that provided vital command and control services. Despite this growing dependence on software control and monitoring, there has been no consistent application of software safety practices and methodology to NASA's projects with safety critical software. Led by the NASA Headquarters Office of Safety and Mission Assurance, the NASA Software Safety Standard (STD-18l9.13B) has recently undergone a significant update in an attempt to provide that consistency. This paper will discuss the key features of the new NASA Software Safety Standard. It will start with a brief history of the use and development of software in safety critical applications at NASA. It will then give a brief overview of the NASA Software Working Group and the approach it took to revise the software engineering process across the Agency.
Quantum-dot light-emitting diodes utilizing CdSe /ZnS nanocrystals embedded in TiO2 thin film
NASA Astrophysics Data System (ADS)
Kang, Seung-Hee; Kumar, Ch. Kiran; Lee, Zonghoon; Kim, Kyung-Hyun; Huh, Chul; Kim, Eui-Tae
2008-11-01
Quantum-dot (QD) light-emitting diodes (LEDs) are demonstrated on Si wafers by embedding core-shell CdSe /ZnS nanocrystals in TiO2 thin films via plasma-enhanced metallorganic chemical vapor deposition. The n-TiO2/QDs /p-Si LED devices show typical p-n diode current-voltage and efficient electroluminescence characteristics, which are critically affected by the removal of QD surface ligands. The TiO2/QDs /Si system we presented can offer promising Si-based optoelectronic and electronic device applications utilizing numerous nanocrystals synthesized by colloidal solution chemistry.
A novel 6-DOF parallel robot and its pose errors compensation
NASA Astrophysics Data System (ADS)
Shi, Zhixin; Ye, Meiyan; Luo, Yufeng
2011-10-01
In the traditional security solution conditions, software firewall cannot intercept and respond the invasion before being attacked. And because of the high cost, the hardware firewall does not apply to the security strategy of the end nodes, so we have designed a kind of solution of embedded firewall with hardware and software. With ARM embedding Linux operating system, we have designed packet filter module and intrusion detection module to implement the basic function of firewall. Experiments and results show that that firewall has the advantages of low cost, high processing speed, high safety and the application of the computer terminals. This paper focuses on packet filtering module design and implementation.
Casing pipe damage detection with optical fiber sensors: a case study in oil well constructions
NASA Astrophysics Data System (ADS)
Zhou, Zhi; He, Jianping; Huang, Minghua; He, Jun; Ou, Jinping; Chen, Genda
2010-04-01
Casing pipes in oil well constructions may suddenly buckle inward as their inside and outside hydrostatic pressure difference increases. For the safety of construction workers and the steady development of oil industries, it is critically important to measure the stress state of a casing pipe. This study develops a rugged, real-time monitoring, and warning system that combines the distributed Brillouin Scattering Time Domain Reflectometry (BOTDR) and the discrete fiber Bragg grating (FBG) measurement. The BOTDR optical fiber sensors were embedded with no optical fiber splice joints in a fiber reinforced polymer (FRP) rebar and the FBG sensors were wrapped in epoxy resins and glass clothes, both installed during the segmental construction of casing pipes. In-situ tests indicate that the proposed sensing system and installation technique can survive the downhole driving process of casing pipes, withstand a harsh service environment, and remain in tact with the casing pipes for compatible strain measurements. The relative error of the measured strains between the distributed and discrete sensors is less than 12%. The FBG sensors successfully measured the maximum horizontal principal stress with a relative error of 6.7% in comparison with a cross multi-pole array acoustic instrument.
Noise switching at a dynamical critical point in a cavity-conductor hybrid
NASA Astrophysics Data System (ADS)
Armour, Andrew D.; Kubala, Björn; Ankerhold, Joachim
2017-12-01
Coupling a mesoscopic conductor to a microwave cavity can lead to fascinating feedback effects which generate strong correlations between the dynamics of photons and charges. We explore the connection between cavity dynamics and charge transport in a model system consisting of a voltage-biased Josephson junction embedded in a high-Q cavity, focusing on the behavior as the system is tuned through a dynamical critical point. On one side of the critical point the noise is strongly suppressed, signaling the existence of a regime of highly coherent transport, but on the other side it switches abruptly to a much larger value. Using a semiclassical approach we show that this behavior arises because of the strongly nonlinear cavity drive generated by the Cooper pairs. We also uncover an equivalence between charge and photonic current noise in the system which opens up a route to detecting the critical behavior through straightforward microwave measurements.
Issues and Methods for Assessing COTS Reliability, Maintainability, and Availability
NASA Technical Reports Server (NTRS)
Schneidewind, Norman F.; Nikora, Allen P.
1998-01-01
Many vendors produce products that are not domain specific (e.g., network server) and have limited functionality (e.g., mobile phone). In contrast, many customers of COTS develop systems that am domain specific (e.g., target tracking system) and have great variability in functionality (e.g., corporate information system). This discussion takes the viewpoint of how the customer can ensure the quality of COTS components. In evaluating the benefits and costs of using COTS, we must consider the environment in which COTS will operate. Thus we must distinguish between using a non-mission critical application like a spreadsheet program to produce a budget and a mission critical application like military strategic and tactical operations. Whereas customers will tolerate an occasional bug in the former, zero tolerance is the rule in the latter. We emphasize the latter because this is the arena where there are major unresolved problems in the application of COTS. Furthermore, COTS components may be embedded in the larger customer system. We refer to these as embedded systems. These components must be reliable, maintainable, and available, and must be with the larger system in order for the customer to benefit from the advertised advantages of lower development and maintenance costs. Interestingly, when the claims of COTS advantages are closely examined, one finds that to a great extent these COTS components consist of hardware and office products, not mission critical software [1]. Obviously, COTS components are different from custom components with respect to one or more of the following attributes: source, development paradigm, safety, reliability, maintainability, availability, security, and other attributes. However, the important question is whether they should be treated differently when deciding to deploy them for operational use; we suggest the answer is no. We use reliability as an example to justify our answer. In order to demonstrate its reliability, a COTS component must pass the same reliability evaluations as the custom components, otherwise the COTS components will be the weakest link in the chain of components and will be the determinant of software system reliability. The challenge is that there will be less information available for evaluating COTS components than for custom components but this does not mean we should despair and do nothing. Actually, there is a lot we can do even in the absence of documentation on COTS components because the customer will have information about how COTS components are to be used in the larger system. To illustrate our approach, we will consider the reliability, maintainability, and availability (RMA) of COTS components as used in larger systems. Finally, COTS suppliers might consider increasing visibility into their products to assist customers in determining the components' fitness for use in a particular application. We offer ideas of information that would be useful to customers, and what vendors might do to provide it.
2014-06-10
Safety is NASA's top priority! The search for innovative new ways to validate and verify is vital for the development of safety-critical systems. Such techniques have been successfully used to assure systems for air traffic control, airplane separation assurance, autopilots, logic designs, medical devices, and other functions that ensure human safety.
Reasons For Physicians Not Adopting Clinical Decision Support Systems: Critical Analysis.
Khairat, Saif; Marc, David; Crosby, William; Al Sanousi, Ali
2018-04-18
Clinical decision support systems (CDSSs) are an integral component of today's health information technologies. They assist with interpretation, diagnosis, and treatment. A CDSS can be embedded throughout the patient safety continuum providing reminders, recommendations, and alerts to health care providers. Although CDSSs have been shown to reduce medical errors and improve patient outcomes, they have fallen short of their full potential. User acceptance has been identified as one of the potential reasons for this shortfall. The purpose of this paper was to conduct a critical review and task analysis of CDSS research and to develop a new framework for CDSS design in order to achieve user acceptance. A critical review of CDSS papers was conducted with a focus on user acceptance. To gain a greater understanding of the problems associated with CDSS acceptance, we conducted a task analysis to identify and describe the goals, user input, system output, knowledge requirements, and constraints from two different perspectives: the machine (ie, the CDSS engine) and the user (ie, the physician). Favorability of CDSSs was based on user acceptance of clinical guidelines, reminders, alerts, and diagnostic suggestions. We propose two models: (1) the user acceptance and system adaptation design model, which includes optimizing CDSS design based on user needs/expectations, and (2) the input-process-output-engagemodel, which reveals to users the processes that govern CDSS outputs. This research demonstrates that the incorporation of the proposed models will improve user acceptance to support the beneficial effects of CDSSs adoption. Ultimately, if a user does not accept technology, this not only poses a threat to the use of the technology but can also pose a threat to the health and well-being of patients. ©Saif Khairat, David Marc, William Crosby, Ali Al Sanousi. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 18.04.2018.
Reliability and Maintainability Engineering - A Major Driver for Safety and Affordability
NASA Technical Reports Server (NTRS)
Safie, Fayssal M.
2011-01-01
The United States National Aeronautics and Space Administration (NASA) is in the midst of an effort to design and build a safe and affordable heavy lift vehicle to go to the moon and beyond. To achieve that, NASA is seeking more innovative and efficient approaches to reduce cost while maintaining an acceptable level of safety and mission success. One area that has the potential to contribute significantly to achieving NASA safety and affordability goals is Reliability and Maintainability (R&M) engineering. Inadequate reliability or failure of critical safety items may directly jeopardize the safety of the user(s) and result in a loss of life. Inadequate reliability of equipment may directly jeopardize mission success. Systems designed to be more reliable (fewer failures) and maintainable (fewer resources needed) can lower the total life cycle cost. The Department of Defense (DOD) and industry experience has shown that optimized and adequate levels of R&M are critical for achieving a high level of safety and mission success, and low sustainment cost. Also, lessons learned from the Space Shuttle program clearly demonstrated the importance of R&M engineering in designing and operating safe and affordable launch systems. The Challenger and Columbia accidents are examples of the severe impact of design unreliability and process induced failures on system safety and mission success. These accidents demonstrated the criticality of reliability engineering in understanding component failure mechanisms and integrated system failures across the system elements interfaces. Experience from the shuttle program also shows that insufficient Reliability, Maintainability, and Supportability (RMS) engineering analyses upfront in the design phase can significantly increase the sustainment cost and, thereby, the total life cycle cost. Emphasis on RMS during the design phase is critical for identifying the design features and characteristics needed for time efficient processing, improved operational availability, and optimized maintenance and logistic support infrastructure. This paper discusses the role of R&M in a program acquisition phase and the potential impact of R&M on safety, mission success, operational availability, and affordability. This includes discussion of the R&M elements that need to be addressed and the R&M analyses that need to be performed in order to support a safe and affordable system design. The paper also provides some lessons learned from the Space Shuttle program on the impact of R&M on safety and affordability.
Implementation of a critical incident reporting system in a neurosurgical department.
Kantelhardt, P; Müller, M; Giese, A; Rohde, V; Kantelhardt, S R
2011-02-01
Critical incident monitoring is an important tool for quality improvement and the maintenance of high safety standards. It was developed for aviation safety and is now widely accepted as a useful tool to reduce medical care-related morbidity and mortality. Despite this widespread acceptance, the literature has no reports on any neurosurgical applications of critical incident monitoring. We describe the introduction of a mono-institutional critical incident reporting system in a neurosurgical department. Furthermore, we have developed a formula to assess possible counterstrategies. All staff members of a neurosurgical department were advised to report critical incidents. The anonymous reporting form contained a box for the description of the incident, several multiple-choice questions on specific risk factors, place and reason for occurrence of the incident, severity of the consequences and suggested counterstrategies. The incident data was entered into an online documentation system (ADKA DokuPik) and evaluated by an external specialist. For data analysis we applied a modified assessment scheme initially designed for flight safety. Data collection was started in September 2008. The average number of reported incidents was 18 per month (currently 216 in total). Most incidents occurred on the neurosurgical ward (64%). Human error was involved in 86% of the reported incidents. The largest group of incidents consisted of medication-related problems. Accordingly, counterstrategies were developed, resulting in a decrease in the relative number of reported medication-related incidents from 42% (March 09) to 30% (September 09). Implementation of the critical incident reporting system presented no technical problems. The reporting rate was high compared to that reported in the current literature. The formulation, evaluation and introduction of specific counterstrategies to guard against selected groups of incidents may improve patient safety in neurosurgical departments. © Georg Thieme Verlag KG Stuttgart · New York.
Xu, Kai; Deng, Qingshan; Cai, Lujun; Ho, Siuchun; Song, Gangbing
2018-04-28
Some of the most severe structural loadings come in the form of blast loads, which may be caused by severe accidents or even terrorist activities. Most commonly after exposure to explosive forces, a structure will suffer from different degrees of damage, and even progress towards a state of collapse. Therefore, damage detection of a structure subject to explosive loads is of importance. This paper proposes a new approach to damage detection of a concrete column structure subjected to blast loads using embedded piezoceramic smart aggregates (SAs). Since the sensors are embedded in the structure, the proposed active-sensing based approach is more sensitive to internal or through cracks than surface damage. In the active sensing approach, the embedded SAs act as actuators and sensors, that can respectively generate and detect stress waves. If the stress wave propagates across a crack, the energy of the wave attenuates, and the reduction of the energy compared to the healthy baseline is indicative of a damage. With a damage index matrix constructed by signals obtained from an array of SAs, cracks caused by blast loads can be detected throughout the structure. Conventional sensing methods such as the measurement of dynamic strain and acceleration were included in the experiment. Since columns are critical elements needed to prevent structural collapse, knowledge of their integrity and damage conditions is essential for safety after exposure to blast loads. In this research, a concrete column with embedded SAs was chosen as the specimen, and a series of explosive tests were conducted on the column. Experimental results reveal that surface damages, though appear severe, cause minor changes in the damage index, and through cracks result in significant increase of the damage index, demonstrating the effectiveness of the active sensing, enabled by embedded SAs, in damage monitoring of the column under blast loads, and thus providing a reliable indication of structural integrity in the event of blast loads.
Damage Detection of a Concrete Column Subject to Blast Loads Using Embedded Piezoceramic Transducers
Deng, Qingshan; Cai, Lujun; Ho, Siuchun; Song, Gangbing
2018-01-01
Some of the most severe structural loadings come in the form of blast loads, which may be caused by severe accidents or even terrorist activities. Most commonly after exposure to explosive forces, a structure will suffer from different degrees of damage, and even progress towards a state of collapse. Therefore, damage detection of a structure subject to explosive loads is of importance. This paper proposes a new approach to damage detection of a concrete column structure subjected to blast loads using embedded piezoceramic smart aggregates (SAs). Since the sensors are embedded in the structure, the proposed active-sensing based approach is more sensitive to internal or through cracks than surface damage. In the active sensing approach, the embedded SAs act as actuators and sensors, that can respectively generate and detect stress waves. If the stress wave propagates across a crack, the energy of the wave attenuates, and the reduction of the energy compared to the healthy baseline is indicative of a damage. With a damage index matrix constructed by signals obtained from an array of SAs, cracks caused by blast loads can be detected throughout the structure. Conventional sensing methods such as the measurement of dynamic strain and acceleration were included in the experiment. Since columns are critical elements needed to prevent structural collapse, knowledge of their integrity and damage conditions is essential for safety after exposure to blast loads. In this research, a concrete column with embedded SAs was chosen as the specimen, and a series of explosive tests were conducted on the column. Experimental results reveal that surface damages, though appear severe, cause minor changes in the damage index, and through cracks result in significant increase of the damage index, demonstrating the effectiveness of the active sensing, enabled by embedded SAs, in damage monitoring of the column under blast loads, and thus providing a reliable indication of structural integrity in the event of blast loads. PMID:29710807
Prompt Global Strike: China and the Spear
2014-04-01
longer range systems that are embedded in a larger system of advanced C4ISR is also evidenced by studies that detail China’s long-range hypersonic...to view U.S. PGS as a threat to Beijing’s conventional and nuclear weapons systems , as well as its command and control centers. With the breadth of...U.S. platforms defined as PGS-related systems in China, its analysts have not ruled out their delivery of nuclear weapons. Despite its criticism of
Aviation Weather Information Communications Study (AWIN). Phase 1 and 2
NASA Technical Reports Server (NTRS)
Ball, J. W.; Herron, R. G.; Nozawa, E. T.; Thomas, E. A.; Witchey, R. D.
2000-01-01
This two part study examines the communication requirements to provide weather information in the cockpit as well as public and private communication systems available to address the requirements. Ongoing research projects combined with user needs for weather related information are used to identify and describe potential weather products that address decision support in three time frames: Far-Term Strategic, Near-Term Strategic and Tactical. Data requirements of these future products are identified and quantified. Communications systems and technologies available in the public as well as private sector are analyzed to identify potential solutions. Recommendations for further research identify cost, performance, and safety benefits to justify the investment. The study concludes that not all weather information has the same level of urgency to safety-of-flight and some information is more critical to one category of flight than another. Specific weather products need to be matched with communication systems with appropriate levels of reliability to support the criticality of the information. Available bandwidth for highly critical information should be preserved and dedicated to safety. Meanwhile, systems designed for in-flight-entertainment and other passenger/crew services could be used to support less critical information that is used only for planning and economic decision support.
The European space suit, a design for productivity and crew safety
NASA Astrophysics Data System (ADS)
Skoog, A. Ingemar; Berthier, S.; Ollivier, Y.
In order to fulfil the two major mission objectives, i.e. support planned and unplanned external servicing of the COLUMBUS FFL and support the HERMES vehicle for safety critical operations and emergencies, the European Space Suit System baseline configuration incorporates a number of design features, which shall enhance the productivity and the crew safety of EVA astronauts. The work in EVA is today - and will be for several years - a manual work. Consequently, to improve productivity, the first challenge is to design a suit enclosure which minimizes movement restrictions and crew fatigue. It is covered by the "ergonomic" aspect of the suit design. Furthermore, it is also necessary to help the EVA crewmember in his work, by giving him the right information at the right time. Many solutions exist in this field of Man-Machine Interface, from a very simple system, based on cuff check lists, up to advanced systems, including Head-Up Displays. The design concept for improved productivity encompasses following features: • easy donning/doffing thru rear entry, • suit ergonomy optimisation, • display of operational information in alpha-numerical and graphical from, and • voice processing for operations and safety critical information. Concerning crew safety the major design features are: • a lower R-factor for emergency EVA operations thru incressed suit pressure, • zero prebreath conditions for normal operations, • visual and voice processing of all safety critical functions, and • an autonomous life support system to permit unrestricted operations around HERMES and the CFFL. The paper analyses crew safety and productivity criteria and describes how these features are being built into the design of the European Space Suit System.
Automated Analysis of Stateflow Models
NASA Technical Reports Server (NTRS)
Bourbouh, Hamza; Garoche, Pierre-Loic; Garion, Christophe; Gurfinkel, Arie; Kahsaia, Temesghen; Thirioux, Xavier
2017-01-01
Stateflow is a widely used modeling framework for embedded and cyber physical systems where control software interacts with physical processes. In this work, we present a framework a fully automated safety verification technique for Stateflow models. Our approach is two-folded: (i) we faithfully compile Stateflow models into hierarchical state machines, and (ii) we use automated logic-based verification engine to decide the validity of safety properties. The starting point of our approach is a denotational semantics of State flow. We propose a compilation process using continuation-passing style (CPS) denotational semantics. Our compilation technique preserves the structural and modal behavior of the system. The overall approach is implemented as an open source toolbox that can be integrated into the existing Mathworks Simulink Stateflow modeling framework. We present preliminary experimental evaluations that illustrate the effectiveness of our approach in code generation and safety verification of industrial scale Stateflow models.
Certification of COTS Software in NASA Human Rated Flight Systems
NASA Technical Reports Server (NTRS)
Goforth, Andre
2012-01-01
Adoption of commercial off-the-shelf (COTS) products in safety critical systems has been seen as a promising acquisition strategy to improve mission affordability and, yet, has come with significant barriers and challenges. Attempts to integrate COTS software components into NASA human rated flight systems have been, for the most part, complicated by verification and validation (V&V) requirements necessary for flight certification per NASA s own standards. For software that is from COTS sources, and, in general from 3rd party sources, either commercial, government, modified or open source, the expectation is that it meets the same certification criteria as those used for in-house and that it does so as if it were built in-house. The latter is a critical and hidden issue. This paper examines the longstanding barriers and challenges in the use of 3rd party software in safety critical systems and cover recent efforts to use COTS software in NASA s Multi-Purpose Crew Vehicle (MPCV) project. It identifies some core artifacts that without them, the use of COTS and 3rd party software is, for all practical purposes, a nonstarter for affordable and timely insertion into flight critical systems. The paper covers the first use in a flight critical system by NASA of COTS software that has prior FAA certification heritage, which was shown to meet the RTCA-DO-178B standard, and how this certification may, in some cases, be leveraged to allow the use of analysis in lieu of testing. Finally, the paper proposes the establishment of an open source forum for development of safety critical 3rd party software.
Flexible thin-film battery based on graphene-oxide embedded in solid polymer electrolyte
NASA Astrophysics Data System (ADS)
Kammoun, M.; Berg, S.; Ardebili, H.
2015-10-01
Enhanced safety of flexible batteries is an imperative objective due to the intimate interaction of such devices with human organs such as flexible batteries that are integrated with touch-screens or embedded in clothing or space suits. In this study, the fabrication and testing of a high performance thin-film Li-ion battery (LIB) is reported that is both flexible and relatively safer compared to the conventional electrolyte based batteries. The concept is facilitated by the use of solid polymer nanocomposite electrolyte, specifically, composed of polyethylene oxide (PEO) matrix and 1 wt% graphene oxide (GO) nanosheets. The flexible LIB exhibits a high maximum operating voltage of 4.9 V, high capacity of 0.13 mA h cm-2 and an energy density of 4.8 mW h cm-3. The battery is encapsulated using a simple lamination method that is economical and scalable. The laminated battery shows robust mechanical flexibility over 6000 bending cycles and excellent electrochemical performance in both flat and bent configurations. Finite element analysis (FEA) of the LIB provides critical insights into the evolution of mechanical stresses during lamination and bending.Enhanced safety of flexible batteries is an imperative objective due to the intimate interaction of such devices with human organs such as flexible batteries that are integrated with touch-screens or embedded in clothing or space suits. In this study, the fabrication and testing of a high performance thin-film Li-ion battery (LIB) is reported that is both flexible and relatively safer compared to the conventional electrolyte based batteries. The concept is facilitated by the use of solid polymer nanocomposite electrolyte, specifically, composed of polyethylene oxide (PEO) matrix and 1 wt% graphene oxide (GO) nanosheets. The flexible LIB exhibits a high maximum operating voltage of 4.9 V, high capacity of 0.13 mA h cm-2 and an energy density of 4.8 mW h cm-3. The battery is encapsulated using a simple lamination method that is economical and scalable. The laminated battery shows robust mechanical flexibility over 6000 bending cycles and excellent electrochemical performance in both flat and bent configurations. Finite element analysis (FEA) of the LIB provides critical insights into the evolution of mechanical stresses during lamination and bending. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04339e
The adaptive safety analysis and monitoring system
NASA Astrophysics Data System (ADS)
Tu, Haiying; Allanach, Jeffrey; Singh, Satnam; Pattipati, Krishna R.; Willett, Peter
2004-09-01
The Adaptive Safety Analysis and Monitoring (ASAM) system is a hybrid model-based software tool for assisting intelligence analysts to identify terrorist threats, to predict possible evolution of the terrorist activities, and to suggest strategies for countering terrorism. The ASAM system provides a distributed processing structure for gathering, sharing, understanding, and using information to assess and predict terrorist network states. In combination with counter-terrorist network models, it can also suggest feasible actions to inhibit potential terrorist threats. In this paper, we will introduce the architecture of the ASAM system, and discuss the hybrid modeling approach embedded in it, viz., Hidden Markov Models (HMMs) to detect and provide soft evidence on the states of terrorist network nodes based on partial and imperfect observations, and Bayesian networks (BNs) to integrate soft evidence from multiple HMMs. The functionality of the ASAM system is illustrated by way of application to the Indian Airlines Hijacking, as modeled from open sources.
Advanced vehicle dynamics of heavy trucks with the perspective of road safety
NASA Astrophysics Data System (ADS)
Trigell, Annika Stensson; Rothhämel, Malte; Pauwelussen, Joop; Kural, Karel
2017-10-01
This paper presents state-of-the art within advanced vehicle dynamics of heavy trucks with the perspective of road safety. The most common accidents with heavy trucks involved are truck against passenger cars. Safety critical situations are for example loss of control (such as rollover and lateral stability) and a majority of these occur during speed when cornering. Other critical situations are avoidance manoeuvre and road edge recovery. The dynamic behaviour of heavy trucks have significant differences compared to passenger cars and as a consequence, successful application of vehicle dynamic functions for enhanced safety of trucks might differ from the functions in passenger cars. Here, the differences between vehicle dynamics of heavy trucks and passenger cars are clarified. Advanced vehicle dynamics solutions with the perspective of road safety of trucks are presented, beginning with the topic vehicle stability, followed by the steering system, the braking system and driver assistance systems that differ in some way from that of passenger cars as well.
Perfetti, Christopher M.; Rearden, Bradley T.
2016-03-01
The sensitivity and uncertainty analysis tools of the ORNL SCALE nuclear modeling and simulation code system that have been developed over the last decade have proven indispensable for numerous application and design studies for nuclear criticality safety and reactor physics. SCALE contains tools for analyzing the uncertainty in the eigenvalue of critical systems, but cannot quantify uncertainty in important neutronic parameters such as multigroup cross sections, fuel fission rates, activation rates, and neutron fluence rates with realistic three-dimensional Monte Carlo simulations. A more complete understanding of the sources of uncertainty in these design-limiting parameters could lead to improvements in processmore » optimization, reactor safety, and help inform regulators when setting operational safety margins. A novel approach for calculating eigenvalue sensitivity coefficients, known as the CLUTCH method, was recently explored as academic research and has been found to accurately and rapidly calculate sensitivity coefficients in criticality safety applications. The work presented here describes a new method, known as the GEAR-MC method, which extends the CLUTCH theory for calculating eigenvalue sensitivity coefficients to enable sensitivity coefficient calculations and uncertainty analysis for a generalized set of neutronic responses using high-fidelity continuous-energy Monte Carlo calculations. Here, several criticality safety systems were examined to demonstrate proof of principle for the GEAR-MC method, and GEAR-MC was seen to produce response sensitivity coefficients that agreed well with reference direct perturbation sensitivity coefficients.« less
Untangling Brain-Wide Dynamics in Consciousness by Cross-Embedding
Tajima, Satohiro; Yanagawa, Toru; Fujii, Naotaka; Toyoizumi, Taro
2015-01-01
Brain-wide interactions generating complex neural dynamics are considered crucial for emergent cognitive functions. However, the irreducible nature of nonlinear and high-dimensional dynamical interactions challenges conventional reductionist approaches. We introduce a model-free method, based on embedding theorems in nonlinear state-space reconstruction, that permits a simultaneous characterization of complexity in local dynamics, directed interactions between brain areas, and how the complexity is produced by the interactions. We demonstrate this method in large-scale electrophysiological recordings from awake and anesthetized monkeys. The cross-embedding method captures structured interaction underlying cortex-wide dynamics that may be missed by conventional correlation-based analysis, demonstrating a critical role of time-series analysis in characterizing brain state. The method reveals a consciousness-related hierarchy of cortical areas, where dynamical complexity increases along with cross-area information flow. These findings demonstrate the advantages of the cross-embedding method in deciphering large-scale and heterogeneous neuronal systems, suggesting a crucial contribution by sensory-frontoparietal interactions to the emergence of complex brain dynamics during consciousness. PMID:26584045
Ensuring the validity of calculated subcritical limits
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clark, H.K.
1977-01-01
The care taken at the Savannah River Laboratory and Plant to ensure the validity of calculated subcritical limits is described. Close attention is given to ANSI N16.1-1975, ''Validation of Calculational Methods for Nuclear Criticality Safety.'' The computer codes used for criticality safety computations, which are listed and are briefly described, have been placed in the SRL JOSHUA system to facilitate calculation and to reduce input errors. A driver module, KOKO, simplifies and standardizes input and links the codes together in various ways. For any criticality safety evaluation, correlations of the calculational methods are made with experiment to establish bias. Occasionallymore » subcritical experiments are performed expressly to provide benchmarks. Calculated subcritical limits contain an adequate but not excessive margin to allow for uncertainty in the bias. The final step in any criticality safety evaluation is the writing of a report describing the calculations and justifying the margin.« less
Rimmed and edge thickened Stodola shaped flywheel
Kulkarni, Satish V.; Stone, Richard G.
1983-01-01
A flywheel (10) is described that is useful for energy storage in a hybrid vehicle automotive power system or in some stationary applications. The flywheel (10) has a body (15) composed of essentially planar isotropic high strength material. The flywheel (10) body (15) is enclosed by a rim (50) of circumferentially wound fiber (2) embedded in resin (3). The rim (50) promotes flywheel (10) safety and survivability. The flywheel (10) has a truncated and edge thickened Stodola shape designed to optimize system mass and energy storage capability.
Nonlinear soil parameter effects on dynamic embedment of offshore pipeline on soft clay
NASA Astrophysics Data System (ADS)
Yu, Su Young; Choi, Han Suk; Lee, Seung Keon; Park, Kyu-Sik; Kim, Do Kyun
2015-06-01
In this paper, the effects of nonlinear soft clay on dynamic embedment of offshore pipeline were investigated. Seabed embedment by pipe-soil interactions has impacts on the structural boundary conditions for various subsea structures such as pipeline, riser, pile, and many other systems. A number of studies have been performed to estimate real soil behavior, but their estimation of seabed embedment has not been fully identified and there are still many uncertainties. In this regards, comparison of embedment between field survey and existing empirical models has been performed to identify uncertainties and investigate the effect of nonlinear soil parameter on dynamic embedment. From the comparison, it is found that the dynamic embedment with installation effects based on nonlinear soil model have an influence on seabed embedment. Therefore, the pipe embedment under dynamic condition by nonlinear parameters of soil models was investigated by Dynamic Embedment Factor (DEF) concept, which is defined as the ratio of the dynamic and static embedment of pipeline, in order to overcome the gap between field embedment and currently used empirical and numerical formula. Although DEF through various researches is suggested, its range is too wide and it does not consider dynamic laying effect. It is difficult to find critical parameters that are affecting to the embedment result. Therefore, the study on dynamic embedment factor by soft clay parameters of nonlinear soil model was conducted and the sensitivity analyses about parameters of nonlinear soil model were performed as well. The tendency on dynamic embedment factor was found by conducting numerical analyses using OrcaFlex software. It is found that DEF was influenced by shear strength gradient than other factors. The obtained results will be useful to understand the pipe embedment on soft clay seabed for applying offshore pipeline designs such as on-bottom stability and free span analyses.
Coordinated traffic incident management using the I-Net embedded sensor architecture
NASA Astrophysics Data System (ADS)
Dudziak, Martin J.
1999-01-01
The I-Net intelligent embedded sensor architecture enables the reconfigurable construction of wide-area remote sensing and data collection networks employing diverse processing and data acquisition modules communicating over thin- server/thin-client protocols. Adaptive initially for operation using mobile remotely-piloted vehicle platforms such as small helicopter robots such as the Hornet and Ascend-I, the I-Net architecture lends itself to a critical problem in the management of both spontaneous and planned traffic congestion and rerouting over major interstate thoroughfares such as the I-95 Corridor. Pre-programmed flight plans and ad hoc operator-assisted navigation of the lightweight helicopter, using an auto-pilot and gyroscopic stabilization augmentation units, allows daytime or nighttime over-the-horizon flights of the unit to collect and transmit real-time video imagery that may be stored or transmitted to other locations. With on-board GPS and ground-based pattern recognition capabilities to augment the standard video collection process, this approach enables traffic management and emergency response teams to plan and assist real-time in the adjustment of traffic flows in high- density or congested areas or during dangerous road conditions such as during ice, snow, and hurricane storms. The I-Net architecture allows for integration of land-based and roadside sensors within a comprehensive automated traffic management system with communications to and form an airborne or other platform to devices in the network other than human-operated desktop computers, thereby allowing more rapid assimilation and response for critical data. Experiments have been conducted using several modified platforms and standard video and still photographic equipment. Current research and development is focused upon modification of the modular instrumentation units in order to accommodate faster loading and reloading of equipment onto the RPV, extension of the I-Net architecture to enable RPV-to-RPV signaling and control, and refinement of safety and emergency mechanisms to handle RPV mechanical failure during flight.
ERIC Educational Resources Information Center
Contrino, Jacline L.
2016-01-01
Demonstrating library impact on student success is critical for all academic libraries today. This article discusses how the library of a large online university serving non-traditional students evaluated how customized point-of-need learning objects (LOs) embedded in the learning management system impacted student learning. Using a comprehensive…
Model Transformation for a System of Systems Dependability Safety Case
NASA Technical Reports Server (NTRS)
Murphy, Judy; Driskell, Stephen B.
2010-01-01
Software plays an increasingly larger role in all aspects of NASA's science missions. This has been extended to the identification, management and control of faults which affect safety-critical functions and by default, the overall success of the mission. Traditionally, the analysis of fault identification, management and control are hardware based. Due to the increasing complexity of system, there has been a corresponding increase in the complexity in fault management software. The NASA Independent Validation & Verification (IV&V) program is creating processes and procedures to identify, and incorporate safety-critical software requirements along with corresponding software faults so that potential hazards may be mitigated. This Specific to Generic ... A Case for Reuse paper describes the phases of a dependability and safety study which identifies a new, process to create a foundation for reusable assets. These assets support the identification and management of specific software faults and, their transformation from specific to generic software faults. This approach also has applications to other systems outside of the NASA environment. This paper addresses how a mission specific dependability and safety case is being transformed to a generic dependability and safety case which can be reused for any type of space mission with an emphasis on software fault conditions.
NASA Astrophysics Data System (ADS)
Bucheli, D.; Caprara, S.; Castellani, C.; Grilli, M.
2013-02-01
Motivated by recent experimental data on thin film superconductors and oxide interfaces, we propose a random-resistor network apt to describe the occurrence of a metal-superconductor transition in a two-dimensional electron system with disorder on the mesoscopic scale. We consider low-dimensional (e.g. filamentary) structures of a superconducting cluster embedded in the two-dimensional network and we explore the separate effects and the interplay of the superconducting structure and of the statistical distribution of local critical temperatures. The thermal evolution of the resistivity is determined by a numerical calculation of the random-resistor network and, for comparison, a mean-field approach called effective medium theory (EMT). Our calculations reveal the relevance of the distribution of critical temperatures for clusters with low connectivity. In addition, we show that the presence of spatial correlations requires a modification of standard EMT to give qualitative agreement with the numerical results. Applying the present approach to an LaTiO3/SrTiO3 oxide interface, we find that the measured resistivity curves are compatible with a network of spatially dense but loosely connected superconducting islands.
Critical care nursing: Embedded complex systems.
Trinier, Ruth; Liske, Lori; Nenadovic, Vera
2016-01-01
Variability in parameters such as heart rate, respiratory rate and blood pressure defines healthy physiology and the ability of the person to adequately respond to stressors. Critically ill patients have lost this variability and require highly specialized nursing care to support life and monitor changes in condition. The critical care environment is a dynamic system through which information flows. The critical care unit is typically designed as a tree structure with generally one attending physician and multiple nurses and allied health care professionals. Information flow through the system allows for identification of deteriorating patient status and timely interventionfor rescue from further deleterious effects. Nurses provide the majority of direct patient care in the critical care setting in 2:1, 1:1 or 1:2 nurse-to-patient ratios. The bedside nurse-critically ill patient relationship represents the primary, real-time feedback loop of information exchange, monitoring and treatment. Variables that enhance information flow through this loop and support timely nursing intervention can improve patient outcomes, while barriers can lead to errors and adverse events. Examining patient information flow in the critical care environment from a dynamic systems perspective provides insights into how nurses deliver effective patient care and prevent adverse events.
Hung, Yu-Ting; Liu, Chi-Te; Peng, I-Chen; Hsu, Chin; Yu, Roch-Chui; Cheng, Kuan-Chen
2015-09-01
To ensure the safety of the peanut butter ice cream manufacture, a Hazard Analysis and Critical Control Point (HACCP) plan has been designed and applied to the production process. Potential biological, chemical, and physical hazards in each manufacturing procedure were identified. Critical control points for the peanut butter ice cream were then determined as the pasteurization and freezing process. The establishment of a monitoring system, corrective actions, verification procedures, and documentation and record keeping were followed to complete the HACCP program. The results of this study indicate that implementing the HACCP system in food industries can effectively enhance food safety and quality while improving the production management. Copyright © 2015. Published by Elsevier B.V.
Ward, Marie; McAuliffe, Eilish; Ní Shé, Éidín; Duffy, Ann; Geary, Una; Cunningham, Una; Holland, Catherine; McDonald, Nick; Egan, Karen; Korpos, Christian
2017-07-17
Healthcare organisations have a responsibility for ensuring that the governance of workplace settings creates a culture that supports good professional practice. Encouraging such a culture needs to start from an understanding of the factors that make it difficult for health professionals to raise issues of concern in relation to patient safety. The focus of this study is to determine whether a customised education intervention, developed as part of the study, with interns and senior house officers (SHOs) can imbue a culture of medical professionalism in relation to patient safety and support junior doctors to raise issues of concern, while shaping a culture of responsiveness and learning. We will use quantitative and qualitative methods to collect data. The sample size will be approximately 200 interns and SHOs across the two hospital sites. Two surveys will be included with one measuring leadership inclusiveness and psychological safety and a second capturing information on safety concerns that participants may have witnessed in their places of work. The PlayDecide embedded learning intervention will be developed with key stakeholders. This will be trialled in the middle stage of data collection for both interns and SHOs. A detailed content analysis will be conducted on the surveys to assess any changes in reporting following the PlayDecide intervention. This will be compared with the incident reporting levels and the results of the preintervention and postintervention leadership inclusiveness and psychological safety survey. Statistical analysis will be conducted using SPSS. Differences will be considered statistically significant at p<0.05. Semistructured interviews using a critical incident technique will be used for the ongoing analysis and evaluation of the project. These will be transcribed, de-identified and coded into themes. The study has been granted ethics approval from University College Dublin (Ref. LS-15-19-Ward-McAuliffe: Imbuing Medical Professionalism in Relation to Safety). The study results will be disseminated through peer-reviewed publications. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Influence Map Methodology for Evaluating Systemic Safety Issues
NASA Technical Reports Server (NTRS)
2008-01-01
"Raising the bar" in safety performance is a critical challenge for many organizations, including Kennedy Space Center. Contributing-factor taxonomies organize information about the reasons accidents occur and therefore are essential elements of accident investigations and safety reporting systems. Organizations must balance efforts to identify causes of specific accidents with efforts to evaluate systemic safety issues in order to become more proactive about improving safety. This project successfully addressed the following two problems: (1) methods and metrics to support the design of effective taxonomies are limited and (2) influence relationships among contributing factors are not explicitly modeled within a taxonomy.
Cynthia Szydlek Photo of Cynthia Szydlek Cynthia Szydlek NWTC Training Coordinator/Project Support increased safety expectations and comply with comprehensive training requirements. She maintains the NWTC's Environmental, Health, and Safety (EHS) training and safety management systems and ensures all critical on-site
ERIC Educational Resources Information Center
Epperly, Anna C.
2017-01-01
This qualitative, collective case study documented the development of the self-efficacy beliefs of special education preservice candidates during one semester of a course-embedded field experience in a small, private, faith-based university in the Midwest. Interviews of candidates regarding critical incidents in field experiences as documented by…
Vicente, K
2003-01-01
There is a tendency to assume that medical error can be stamped out by automation. Technology may improve patient safety, but cognitive engineering research findings in several complex safety critical systems, including both aviation and health care, show that more is not always better. Less sophisticated technological systems can sometimes lead to better performance than more sophisticated systems. This "less is more" effect arises because safety critical systems are open systems where unanticipated events are bound to occur. In these contexts, decision support provided by a technological aid will be less than perfect because there will always be situations that the technology cannot accommodate. Designing sophisticated automation that suggests an uncertain course of action seems to encourage people to accept the imperfect advice, even though information to decide independently on a better course of action is available. It may be preferable to create more modest designs that merely provide feedback about the current state of affairs or that critique human generated solutions than to rush to automate by creating sophisticated technological systems that recommend (fallible) courses of action. PMID:12897363
Verification and Validation in a Rapid Software Development Process
NASA Technical Reports Server (NTRS)
Callahan, John R.; Easterbrook, Steve M.
1997-01-01
The high cost of software production is driving development organizations to adopt more automated design and analysis methods such as rapid prototyping, computer-aided software engineering (CASE) tools, and high-level code generators. Even developers of safety-critical software system have adopted many of these new methods while striving to achieve high levels Of quality and reliability. While these new methods may enhance productivity and quality in many cases, we examine some of the risks involved in the use of new methods in safety-critical contexts. We examine a case study involving the use of a CASE tool that automatically generates code from high-level system designs. We show that while high-level testing on the system structure is highly desirable, significant risks exist in the automatically generated code and in re-validating releases of the generated code after subsequent design changes. We identify these risks and suggest process improvements that retain the advantages of rapid, automated development methods within the quality and reliability contexts of safety-critical projects.
Hearns, S; Shirley, P J
2006-01-01
Retrieval and transfer of critically ill and injured patients is a high risk activity. Risk can be minimised with robust safety and clinical governance systems in place. This article describes the various governance systems that can be employed to optimise safety and efficiency in retrieval services. These include operating procedure development, equipment management, communications procedures, crew resource management, significant event analysis, audit and training. PMID:17130608
DOT National Transportation Integrated Search
1995-09-01
This report describes the development of a methodology designed to assure that a sufficiently high level of safety is achieved and maintained in computer-based systems which perform safety critical functions in high-speed rail or magnetic levitation ...
ERIC Educational Resources Information Center
Jacobsen, Jared; Ackermann, Richard; Eguez, Jane; Ganguli, Debalina; Rickard, Patricia; Taylor, Linda
2011-01-01
A computer adaptive test (CAT) is a delivery methodology that serves the larger goals of the assessment system in which it is embedded. A thorough analysis of the assessment system for which a CAT is being designed is critical to ensure that the delivery platform is appropriate and addresses all relevant complexities. As such, a CAT engine must be…
Information Retrieval and Criticality in Parity-Time-Symmetric Systems.
Kawabata, Kohei; Ashida, Yuto; Ueda, Masahito
2017-11-10
By investigating information flow between a general parity-time (PT-)symmetric non-Hermitian system and an environment, we find that the complete information retrieval from the environment can be achieved in the PT-unbroken phase, whereas no information can be retrieved in the PT-broken phase. The PT-transition point thus marks the reversible-irreversible criticality of information flow, around which many physical quantities such as the recurrence time and the distinguishability between quantum states exhibit power-law behavior. Moreover, by embedding a PT-symmetric system into a larger Hilbert space so that the entire system obeys unitary dynamics, we reveal that behind the information retrieval lies a hidden entangled partner protected by PT symmetry. Possible experimental situations are also discussed.
Verification and Validation for Flight-Critical Systems (VVFCS)
NASA Technical Reports Server (NTRS)
Graves, Sharon S.; Jacobsen, Robert A.
2010-01-01
On March 31, 2009 a Request for Information (RFI) was issued by NASA s Aviation Safety Program to gather input on the subject of Verification and Validation (V & V) of Flight-Critical Systems. The responses were provided to NASA on or before April 24, 2009. The RFI asked for comments in three topic areas: Modeling and Validation of New Concepts for Vehicles and Operations; Verification of Complex Integrated and Distributed Systems; and Software Safety Assurance. There were a total of 34 responses to the RFI, representing a cross-section of academic (26%), small & large industry (47%) and government agency (27%).
Towards A Comprehensive Consideration of Epistemic Questions in Software System Safety
NASA Technical Reports Server (NTRS)
Holloway, C. M.; Johnson, Chris W.
2009-01-01
For any software system upon which lives depend, the most important question one can ask about it is, 'How do we know the system is safe?' Despite the critical importance of this question, no widely accepted, generally applicable answer exists. Instead, debate continues to rage over the question, with theorists and practitioners quarrelling with each other and amongst themselves. This paper suggests a possible way forward towards quelling the quarrels, based on refining the critical safety question into additional questions, which may be more likely to have answers on which a consensus can be reached.
A Possible Approach for Addressing Neglected Human Factors Issues of Systems Engineering
NASA Technical Reports Server (NTRS)
Johnson, Christopher W.; Holloway, C. Michael
2011-01-01
The increasing complexity of safety-critical applications has led to the introduction of decision support tools in the transportation and process industries. Automation has also been introduced to support operator intervention in safety-critical applications. These innovations help reduce overall operator workload, and filter application data to maximize the finite cognitive and perceptual resources of system operators. However, these benefits do not come without a cost. Increased computational support for the end-users of safety-critical applications leads to increased reliance on engineers to monitor and maintain automated systems and decision support tools. This paper argues that by focussing on the end-users of complex applications, previous research has tended to neglect the demands that are being placed on systems engineers. The argument is illustrated through discussing three recent accidents. The paper concludes by presenting a possible strategy for building and using highly automated systems based on increased attention by management and regulators, improvements in competency and training for technical staff, sustained support for engineering team resource management, and the development of incident reporting systems for infrastructure failures. This paper represents preliminary work, about which we seek comments and suggestions.
NASA Technical Reports Server (NTRS)
Belcastro, Christine M.
2010-01-01
Loss of control remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft loss-of-control accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents and reducing them will require a holistic integrated intervention capability. Future onboard integrated system technologies developed for preventing loss of vehicle control accidents must be able to assure safe operation under the associated off-nominal conditions. The transition of these technologies into the commercial fleet will require their extensive validation and verification (V and V) and ultimate certification. The V and V of complex integrated systems poses major nontrivial technical challenges particularly for safety-critical operation under highly off-nominal conditions associated with aircraft loss-of-control events. This paper summarizes the V and V problem and presents a proposed process that could be applied to complex integrated safety-critical systems developed for preventing aircraft loss-of-control accidents. A summary of recent research accomplishments in this effort is also provided.
ERIC Educational Resources Information Center
Slater, Beverley L.; Lawton, Rebecca; Armitage, Gerry; Bibby, John; Wright, John
2012-01-01
Introduction: Despite an explosion of interest in improving safety and reducing error in health care, one important aspect of patient safety that has received little attention is a systematic approach to education and training for the whole health care workforce. This article describes an evaluation of an innovative multiprofessional, team-based…
Fault tree applications within the safety program of Idaho Nuclear Corporation
NASA Technical Reports Server (NTRS)
Vesely, W. E.
1971-01-01
Computerized fault tree analyses are used to obtain both qualitative and quantitative information about the safety and reliability of an electrical control system that shuts the reactor down when certain safety criteria are exceeded, in the design of a nuclear plant protection system, and in an investigation of a backup emergency system for reactor shutdown. The fault tree yields the modes by which the system failure or accident will occur, the most critical failure or accident causing areas, detailed failure probabilities, and the response of safety or reliability to design modifications and maintenance schemes.
SAFEGUARD: An Assured Safety Net Technology for UAS
NASA Technical Reports Server (NTRS)
Dill, Evan T.; Young, Steven D.; Hayhurst, Kelly J.
2016-01-01
As demands increase to use unmanned aircraft systems (UAS) for a broad spectrum of commercial applications, regulatory authorities are examining how to safely integrate them without loss of safety or major disruption to existing airspace operations. This work addresses the development of the Safeguard system as an assured safety net technology for UAS. The Safeguard system monitors and enforces conformance to a set of rules defined prior to flight (e.g., geospatial stay-out or stay-in regions, speed limits, altitude limits). Safeguard operates independently of the UAS autopilot and is strategically designed in a way that can be realized by a small set of verifiable functions to simplify compliance with regulatory standards for commercial aircraft. A framework is described that decouples the system from any other devices on the UAS as well as introduces complementary positioning source(s) for applications that require integrity and availability beyond what the Global Positioning System (GPS) can provide. Additionally, the high level logic embedded within the software is presented, as well as the steps being taken toward verification and validation (V&V) of proper functionality. Next, an initial prototype implementation of the described system is disclosed. Lastly, future work including development, testing, and system V&V is summarized.
CRITICALITY SAFETY CONTROLS AND THE SAFETY BASIS AT PFP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kessler, S
2009-04-21
With the implementation of DOE Order 420.1B, Facility Safety, and DOE-STD-3007-2007, 'Guidelines for Preparing Criticality Safety Evaluations at Department of Energy Non-Reactor Nuclear Facilities', a new requirement was imposed that all criticality safety controls be evaluated for inclusion in the facility Documented Safety Analysis (DSA) and that the evaluation process be documented in the site Criticality Safety Program Description Document (CSPDD). At the Hanford site in Washington State the CSPDD, HNF-31695, 'General Description of the FH Criticality Safety Program', requires each facility develop a linking document called a Criticality Control Review (CCR) to document performance of these evaluations. Chapter 5,more » Appendix 5B of HNF-7098, Criticality Safety Program, provided an example of a format for a CCR that could be used in lieu of each facility developing its own CCR. Since the Plutonium Finishing Plant (PFP) is presently undergoing Deactivation and Decommissioning (D&D), new procedures are being developed for cleanout of equipment and systems that have not been operated in years. Existing Criticality Safety Evaluations (CSE) are revised, or new ones written, to develop the controls required to support D&D activities. Other Hanford facilities, including PFP, had difficulty using the basic CCR out of HNF-7098 when first implemented. Interpretation of the new guidelines indicated that many of the controls needed to be elevated to TSR level controls. Criterion 2 of the standard, requiring that the consequence of a criticality be examined for establishing the classification of a control, was not addressed. Upon in-depth review by PFP Criticality Safety staff, it was not clear that the programmatic interpretation of criterion 8C could be applied at PFP. Therefore, the PFP Criticality Safety staff decided to write their own CCR. The PFP CCR provides additional guidance for the evaluation team to use by clarifying the evaluation criteria in DOE-STD-3007-2007. In reviewing documents used in classifying controls for Nuclear Safety, it was noted that DOE-HDBK-1188, 'Glossary of Environment, Health, and Safety Terms', defines an Administrative Control (AC) in terms that are different than typically used in Criticality Safety. As part of this CCR, a new term, Criticality Administrative Control (CAC) was defined to clarify the difference between an AC used for criticality safety and an AC used for nuclear safety. In Nuclear Safety terms, an AC is a provision relating to organization and management, procedures, recordkeeping, assessment, and reporting necessary to ensure safe operation of a facility. A CAC was defined as an administrative control derived in a criticality safety analysis that is implemented to ensure double contingency. According to criterion 2 of Section IV, 'Linkage to the Documented Safety Analysis', of DOESTD-3007-2007, the consequence of a criticality should be examined for the purposes of classifying the significance of a control or component. HNF-PRO-700, 'Safety Basis Development', provides control selection criteria based on consequence and risk that may be used in the development of a Criticality Safety Evaluation (CSE) to establish the classification of a component as a design feature, as safety class or safety significant, i.e., an Engineered Safety Feature (ESF), or as equipment important to safety; or merely provides defense-in-depth. Similar logic is applied to the CACs. Criterion 8C of DOE-STD-3007-2007, as written, added to the confusion of using the basic CCR from HNF-7098. The PFP CCR attempts to clarify this criterion by revising it to say 'Programmatic commitments or general references to control philosophy (e.g., mass control or spacing control or concentration control as an overall control strategy for the process without specific quantification of individual limits) is included in the PFP DSA'. Table 1 shows the PFP methodology for evaluating CACs. This evaluation process has been in use since February of 2008 and has proven to be simple and effective. Each control identified in the applicable new/revised CSE is evaluated via the table. The results of this evaluation are documented in tables attached to the CCR as an appendix, for each CSE, to the base document.« less
Ward, Marie; McDonald, Nick; Morrison, Rabea; Gaynor, Des; Nugent, Tony
2010-02-01
Aircraft maintenance is a highly regulated, safety critical, complex and competitive industry. There is a need to develop innovative solutions to address process efficiency without compromising safety and quality. This paper presents the case that in order to improve a highly complex system such as aircraft maintenance, it is necessary to develop a comprehensive and ecologically valid model of the operational system, which represents not just what is meant to happen, but what normally happens. This model then provides the backdrop against which to change or improve the system. A performance report, the Blocker Report, specific to aircraft maintenance and related to the model was developed gathering data on anything that 'blocks' task or check performance. A Blocker Resolution Process was designed to resolve blockers and improve the current check system. Significant results were obtained for the company in the first trial and implications for safety management systems and hazard identification are discussed. Statement of Relevance: Aircraft maintenance is a safety critical, complex, competitive industry with a need to develop innovative solutions to address process and safety efficiency. This research addresses this through the development of a comprehensive and ecologically valid model of the system linked with a performance reporting and resolution system.
48 CFR 252.246-7003 - Notification of Potential Safety Issues.
Code of Federal Regulations, 2013 CFR
2013-10-01
.... Critical safety item means a part, subassembly, assembly, subsystem, installation equipment, or support... impact for systems, or subsystems, assemblies, subassemblies, or parts integral to a system, acquired by... the extent known at the time of notification; (iv) A point of contact to coordinate problem analysis...
48 CFR 252.246-7003 - Notification of Potential Safety Issues.
Code of Federal Regulations, 2010 CFR
2010-10-01
.... Critical safety item means a part, subassembly, assembly, subsystem, installation equipment, or support... impact for systems, or subsystems, assemblies, subassemblies, or parts integral to a system, acquired by... the extent known at the time of notification; (iv) A point of contact to coordinate problem analysis...
48 CFR 252.246-7003 - Notification of Potential Safety Issues.
Code of Federal Regulations, 2011 CFR
2011-10-01
.... Critical safety item means a part, subassembly, assembly, subsystem, installation equipment, or support... impact for systems, or subsystems, assemblies, subassemblies, or parts integral to a system, acquired by... the extent known at the time of notification; (iv) A point of contact to coordinate problem analysis...
48 CFR 252.246-7003 - Notification of Potential Safety Issues.
Code of Federal Regulations, 2012 CFR
2012-10-01
.... Critical safety item means a part, subassembly, assembly, subsystem, installation equipment, or support... impact for systems, or subsystems, assemblies, subassemblies, or parts integral to a system, acquired by... the extent known at the time of notification; (iv) A point of contact to coordinate problem analysis...
48 CFR 252.246-7003 - Notification of Potential Safety Issues.
Code of Federal Regulations, 2014 CFR
2014-10-01
.... Critical safety item means a part, subassembly, assembly, subsystem, installation equipment, or support... impact for systems, or subsystems, assemblies, subassemblies, or parts integral to a system, acquired by... the extent known at the time of notification; (iv) A point of contact to coordinate problem analysis...
ERIC Educational Resources Information Center
Atkins, Kemal M.
2017-01-01
Crisis management is a critical issue facing higher education. Higher education leaders and campus safety advocates agree that the Virginia Tech massacre changed perceptions and approaches to campus safety at colleges and universities nationally. In the University of North Carolina System, it was the two murders of University of North Carolina at…
Switching theory-based steganographic system for JPEG images
NASA Astrophysics Data System (ADS)
Cherukuri, Ravindranath C.; Agaian, Sos S.
2007-04-01
Cellular communications constitute a significant portion of the global telecommunications market. Therefore, the need for secured communication over a mobile platform has increased exponentially. Steganography is an art of hiding critical data into an innocuous signal, which provide answers to the above needs. The JPEG is one of commonly used format for storing and transmitting images on the web. In addition, the pictures captured using mobile cameras are in mostly in JPEG format. In this article, we introduce a switching theory based steganographic system for JPEG images which is applicable for mobile and computer platforms. The proposed algorithm uses the fact that energy distribution among the quantized AC coefficients varies from block to block and coefficient to coefficient. Existing approaches are effective with a part of these coefficients but when employed over all the coefficients they show there ineffectiveness. Therefore, we propose an approach that works each set of AC coefficients with different frame work thus enhancing the performance of the approach. The proposed system offers a high capacity and embedding efficiency simultaneously withstanding to simple statistical attacks. In addition, the embedded information could be retrieved without prior knowledge of the cover image. Based on simulation results, the proposed method demonstrates an improved embedding capacity over existing algorithms while maintaining a high embedding efficiency and preserving the statistics of the JPEG image after hiding information.
NASA Astrophysics Data System (ADS)
Dulo, D. A.
Safety critical software systems permeate spacecraft, and in a long term venture like a starship would be pervasive in every system of the spacecraft. Yet software failure today continues to plague both the systems and the organizations that develop them resulting in the loss of life, time, money, and valuable system platforms. A starship cannot afford this type of software failure in long journeys away from home. A single software failure could have catastrophic results for the spaceship and the crew onboard. This paper will offer a new approach to developing safe reliable software systems through focusing not on the traditional safety/reliability engineering paradigms but rather by focusing on a new paradigm: Resilience and Failure Obviation Engineering. The foremost objective of this approach is the obviation of failure, coupled with the ability of a software system to prevent or adapt to complex changing conditions in real time as a safety valve should failure occur to ensure safe system continuity. Through this approach, safety is ensured through foresight to anticipate failure and to adapt to risk in real time before failure occurs. In a starship, this type of software engineering is vital. Through software developed in a resilient manner, a starship would have reduced or eliminated software failure, and would have the ability to rapidly adapt should a software system become unstable or unsafe. As a result, long term software safety, reliability, and resilience would be present for a successful long term starship mission.
Cusato, Sueli; Gameiro, Augusto H; Corassin, Carlos H; Sant'ana, Anderson S; Cruz, Adriano G; Faria, José de Assis F; de Oliveira, Carlos Augusto F
2013-01-01
The present study describes the implementation of a food safety system in a dairy processing plant located in the State of São Paulo, Brazil, and the challenges found during the process. In addition, microbiological indicators have been used to assess system's implementation performance. The steps involved in the implementation of a food safety system included a diagnosis of the prerequisites, implementation of the good manufacturing practices (GMPs), sanitation standard operating procedures (SSOPs), training of the food handlers, and hazard analysis and critical control point (HACCP). In the initial diagnosis, conformity with 70.7% (n=106) of the items analyzed was observed. A total of 12 critical control points (CCPs) were identified: (1) reception of the raw milk, (2) storage of the raw milk, (3 and 4) reception of the ingredients and packaging, (5) milk pasteurization, (6 and 7) fermentation and cooling, (8) addition of ingredients, (9) filling, (10) storage of the finished product, (11) dispatching of the product, and (12) sanitization of the equipment. After implementation of the food safety system, a significant reduction in the yeast and mold count was observed (p<0.05). The main difficulties encountered for the implementation of food safety system were related to the implementation of actions established in the flow chart and to the need for constant training/adherence of the workers to the system. Despite this, the implementation of the food safety system was shown to be challenging, but feasible to be reached by small-scale food industries.
Popova, A Yu; Trukhina, G M; Mikailova, O M
In the article there is considered the quality control and safety system implemented in the one of the largest flight catering food production plant for airline passengers and flying squad. The system for the control was based on the Hazard Analysis And Critical Control Points (HACCP) principles and developed hygienic and antiepidemic measures. There is considered the identification of hazard factors at stages of the technical process. There are presented results of the analysis data of monitoring for 6 critical control points over the five-year period. The quality control and safety system permit to decline food contamination risk during acceptance, preparation and supplying of in-flight meal. There was proved the efficiency of the implemented system. There are determined further ways of harmonization and implementation for HACCP principles in the plant.
NASA Technical Reports Server (NTRS)
Carrio, Miguel A., Jr.
1988-01-01
Rapidly emerging technology and methodologies have out-paced the systems development processes' ability to use them effectively, if at all. At the same time, the tools used to build systems are becoming obsolescent themselves as a consequence of the same technology lag that plagues systems development. The net result is that systems development activities have not been able to take advantage of available technology and have become equally dependent on aging and ineffective computer-aided engineering tools. New methods and tools approaches are essential if the demands of non-stop and Mission and Safety Critical (MASC) components are to be met.
A database management capability for Ada
NASA Technical Reports Server (NTRS)
Chan, Arvola; Danberg, SY; Fox, Stephen; Landers, Terry; Nori, Anil; Smith, John M.
1986-01-01
The data requirements of mission critical defense systems have been increasing dramatically. Command and control, intelligence, logistics, and even weapons systems are being required to integrate, process, and share ever increasing volumes of information. To meet this need, systems are now being specified that incorporate data base management subsystems for handling storage and retrieval of information. It is expected that a large number of the next generation of mission critical systems will contain embedded data base management systems. Since the use of Ada has been mandated for most of these systems, it is important to address the issues of providing data base management capabilities that can be closely coupled with Ada. A comprehensive distributed data base management project has been investigated. The key deliverables of this project are three closely related prototype systems implemented in Ada. These three systems are discussed.
SMART Layer and SMART Suitcase for structural health monitoring applications
NASA Astrophysics Data System (ADS)
Lin, Mark; Qing, Xinlin; Kumar, Amrita; Beard, Shawn J.
2001-06-01
Knowledge of integrity of in-service structures can greatly enhance their safety and reliability and lower structural maintenance cost. Current practices limit the extent of real-time knowledge that can be obtained from structures during inspection, are labor-intensive and thereby increase life-cycle costs. Utilization of distributed sensors integrated with the structure is a viable and cost-effective means of monitoring the structure and reducing inspection costs. Acellent Technologies is developing a novel system for actively and passively interrogating the health of a structure through an integrated network of sensors and actuators. Acellent's system comprises of SMART Layers, SMART Suitcase and diagnostic software. The patented SMART Layer is a thin dielectric film with an embedded network of distributed piezoelectric actuators/sensors that can be surface-mounted on metallic structures or embedded inside composite structures. The SMART Suitcase is a portable diagnostic unit designed with multiple sensor/actuator channels to interface with the SMART Layer, generate diagnostic signals from actuators and record measurements from the embedded sensors. With appropriate diagnostic software, Acellent's system can be used for monitoring structural condition and for detecting damage while the structures are in service. This paper enumerates on the SMART Layer and SMART Suitcase and their applicability to composite and metal structures.
Stocks, Flows, and Distribution of Critical Metals in Embedded Electronics in Passenger Vehicles.
Restrepo, Eliette; Løvik, Amund N; Wäger, Patrick; Widmer, Rolf; Lonka, Radek; Müller, Daniel B
2017-02-07
One of the major applications of critical metals (CMs) is in electrical and electronic equipment (EEE), which is increasingly embedded in other products, notably passenger vehicles. However, recycling strategies for future CM quantities in end-of-life vehicles (ELVs) are poorly understood, mainly due to a limited understating of the complexity of automotive embedded EEE. We introduce a harmonization of the network structure of automotive electronics that enables a comprehensive quantification of CMs in all embedded EEE in a vehicle. This network is combined with a material flow analysis along the vehicle lifecycle in Switzerland to quantify the stocks and flows of Ag, Au, Pd, Ru, Dy, La, Nd, and Co in automotive embedded EEE. In vehicles in use, we calculated 5 -2 +3 t precious metals in controllers embedded in all vehicle types and 220 -60 +90 t rare earth elements (REE); found mainly in five electric motors: alternator, starter, radiator-fan and electronic power steering motor embedded in conventional passenger vehicles and drive motor/generator embedded in hybrid and electric vehicles. Dismantling these devices before ELV shredding, as well as postshredder treatment of automobile shredder residue may increase the recovery of CMs from ELVs. Environmental and economic implications of such recycling strategies must be considered.
Limited-scope probabilistic safety analysis for the Los Alamos Meson Physics Facility (LAMPF)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharirli, M.; Rand, J.L.; Sasser, M.K.
1992-01-01
The reliability of instrumentation and safety systems is a major issue in the operation of accelerator facilities. A probabilistic safety analysis was performed or the key safety and instrumentation systems at the Los Alamos Meson Physics Facility (LAMPF). in Phase I of this unique study, the Personnel Safety System (PSS) and the Current Limiters (XLs) were analyzed through the use of the fault tree analyses, failure modes and effects analysis, and criticality analysis. Phase II of the program was done to update and reevaluate the safety systems after the Phase I recommendations were implemented. This paper provides a brief reviewmore » of the studies involved in Phases I and II of the program.« less
Limited-scope probabilistic safety analysis for the Los Alamos Meson Physics Facility (LAMPF)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sharirli, M.; Rand, J.L.; Sasser, M.K.
1992-12-01
The reliability of instrumentation and safety systems is a major issue in the operation of accelerator facilities. A probabilistic safety analysis was performed or the key safety and instrumentation systems at the Los Alamos Meson Physics Facility (LAMPF). in Phase I of this unique study, the Personnel Safety System (PSS) and the Current Limiters (XLs) were analyzed through the use of the fault tree analyses, failure modes and effects analysis, and criticality analysis. Phase II of the program was done to update and reevaluate the safety systems after the Phase I recommendations were implemented. This paper provides a brief reviewmore » of the studies involved in Phases I and II of the program.« less
Feature-based component model for design of embedded systems
NASA Astrophysics Data System (ADS)
Zha, Xuan Fang; Sriram, Ram D.
2004-11-01
An embedded system is a hybrid of hardware and software, which combines software's flexibility and hardware real-time performance. Embedded systems can be considered as assemblies of hardware and software components. An Open Embedded System Model (OESM) is currently being developed at NIST to provide a standard representation and exchange protocol for embedded systems and system-level design, simulation, and testing information. This paper proposes an approach to representing an embedded system feature-based model in OESM, i.e., Open Embedded System Feature Model (OESFM), addressing models of embedded system artifacts, embedded system components, embedded system features, and embedded system configuration/assembly. The approach provides an object-oriented UML (Unified Modeling Language) representation for the embedded system feature model and defines an extension to the NIST Core Product Model. The model provides a feature-based component framework allowing the designer to develop a virtual embedded system prototype through assembling virtual components. The framework not only provides a formal precise model of the embedded system prototype but also offers the possibility of designing variation of prototypes whose members are derived by changing certain virtual components with different features. A case study example is discussed to illustrate the embedded system model.
NASA Astrophysics Data System (ADS)
Godavarthi, Bhavana; Nalajala, Paparao; Ganapuram, Vasavi
2017-08-01
Advanced vehicle monitoring and tracking system based on embedded Linux board and android application is designed and implemented for monitoring the school vehicle from any location A to location B at real time. The present system would make good use of new technology that based on embedded Linux namely Raspberry Pi and Smartphone android application. This system works on GPS/GPRS/GSM SIM900A. GPS finds the current location of the vehicle, GPRS sends the tracking information to the server and the GSM is used for sending alert message to vehicle’s owner mobile. This system is placed inside the vehicle whose position is to be determined on the web page and monitored at real time. There is a comparison between the current vehicle path already specified paths into the file system. Inside the raspberry pi’s file system taken from vehicle owners through android phone using android application. Means the selection of path from location A to B takes place from vehicle owner’s android application which gives more safety and secures traveling to the traveler. Hence the driver drives the vehicle only on the vehicle owner’s specified path. The driver drives the vehicle only on the vehicle owner’s specified path but if the driver drives in wrong path the message alert will be sent from this system to the vehicle owners mobile and also sent speakers alert to driver through audio jack. If the vehicles speed goes beyond the specified value of the speed, then warning message will be sent to owner mobile. This system also takes care of the traveler’s safety by using Gas leakage and Temperature sensors
Designing Crane Controls with Applied Mechanical and Electrical Safety Features
NASA Technical Reports Server (NTRS)
Lytle, Bradford P.; Walczak, Thomas A.
2002-01-01
The use of overhead traveling bridge cranes in many varied applications is common practice. In particular, the use of cranes in the nuclear, military, commercial, aerospace, and other industries can involve safety critical situations. Considerations for Human Injury or Casualty, Loss of Assets, Endangering the Environment, or Economic Reduction must be addressed. Traditionally, in order to achieve additional safety in these applications, mechanical systems have been augmented with a variety of devices. These devices assure that a mechanical component failure shall reduce the risk of a catastrophic loss of the correct and/or safe load carrying capability. ASME NOG-1-1998, (Rules for Construction of Overhead and Gantry Cranes, Top Running Bridge, and Multiple Girder), provides design standards for cranes in safety critical areas. Over and above the minimum safety requirements of todays design standards, users struggle with obtaining a higher degree of reliability through more precise functional specifications while attempting to provide "smart" safety systems. Electrical control systems also may be equipped with protective devices similar to the mechanical design features. Demands for improvement of the cranes "control system" is often recognized, but difficult to quantify for this traditionally "mechanically" oriented market. Finite details for each operation must be examined and understood. As an example, load drift (or small motions) at close tolerances can be unacceptable (and considered critical). To meet these high functional demands encoders and other devices are independently added to control systems to provide motion and velocity feedback to the control drive. This paper will examine the implementation of Programmable Electronic Systems (PES). PES is a term this paper will use to describe any control system utilizing any programmable electronic device such as Programmable Logic Controllers (PLC), or an Adjustable Frequency Drive (AID) 'smart' programmable motion controller. Therefore the use of the term Programmable Electronic Systems (PES) is an encompassing description for a large spectrum of programmable electronic control devices.
Learning Embedded Software Design in an Open 3A Multiuser Laboratory
ERIC Educational Resources Information Center
Shih, Chien-Chou; Hwang, Lain-Jinn
2011-01-01
The need for professional programmers in embedded applications has become critical for industry growth. This need has increased the popularity of embedded software design courses, which are resource-intensive and space-limited in traditional real lab-based instruction. To overcome geographic and time barriers in enhancing practical skills that…
Winkelman, Warren J.; Leonard, Kevin J.
2004-01-01
There are constraints embedded in medical record structure that limit use by patients in self-directed disease management. Through systematic review of the literature from a critical perspective, four characteristics that either enhance or mitigate the influence of medical record structure on patient utilization of an electronic patient record (EPR) system have been identified: environmental pressures, physician centeredness, collaborative organizational culture, and patient centeredness. An evaluation framework is proposed for use when considering adaptation of existing EPR systems for online patient access. Exemplars of patient-accessible EPR systems from the literature are evaluated utilizing the framework. From this study, it appears that traditional information system research and development methods may not wholly capture many pertinent social issues that arise when expanding access of EPR systems to patients. Critically rooted methods such as action research can directly inform development strategies so that these systems may positively influence health outcomes. PMID:14633932
14 CFR 1214.501 - Applicability.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Applicability. 1214.501 Section 1214.501 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mission Critical Space System... the safety and success of mission critical space systems. (b) The provisions of this regulation apply...
14 CFR 1214.501 - Applicability.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Applicability. 1214.501 Section 1214.501 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mission Critical Space System... the safety and success of mission critical space systems. (b) The provisions of this regulation apply...
14 CFR 1214.501 - Applicability.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Applicability. 1214.501 Section 1214.501 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mission Critical Space System... the safety and success of mission critical space systems. (b) The provisions of this regulation apply...
14 CFR 1214.501 - Applicability.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Applicability. 1214.501 Section 1214.501 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mission Critical Space System... the safety and success of mission critical space systems. (b) The provisions of this regulation apply...
Safety Metrics for Human-Computer Controlled Systems
NASA Technical Reports Server (NTRS)
Leveson, Nancy G; Hatanaka, Iwao
2000-01-01
The rapid growth of computer technology and innovation has played a significant role in the rise of computer automation of human tasks in modem production systems across all industries. Although the rationale for automation has been to eliminate "human error" or to relieve humans from manual repetitive tasks, various computer-related hazards and accidents have emerged as a direct result of increased system complexity attributed to computer automation. The risk assessment techniques utilized for electromechanical systems are not suitable for today's software-intensive systems or complex human-computer controlled systems.This thesis will propose a new systemic model-based framework for analyzing risk in safety-critical systems where both computers and humans are controlling safety-critical functions. A new systems accident model will be developed based upon modem systems theory and human cognitive processes to better characterize system accidents, the role of human operators, and the influence of software in its direct control of significant system functions Better risk assessments will then be achievable through the application of this new framework to complex human-computer controlled systems.
NASA's Software Safety Standard
NASA Technical Reports Server (NTRS)
Ramsay, Christopher M.
2007-01-01
NASA relies more and more on software to control, monitor, and verify its safety critical systems, facilities and operations. Since the 1960's there has hardly been a spacecraft launched that does not have a computer on board that will provide command and control services. There have been recent incidents where software has played a role in high-profile mission failures and hazardous incidents. For example, the Mars Orbiter, Mars Polar Lander, the DART (Demonstration of Autonomous Rendezvous Technology), and MER (Mars Exploration Rover) Spirit anomalies were all caused or contributed to by software. The Mission Control Centers for the Shuttle, ISS, and unmanned programs are highly dependant on software for data displays, analysis, and mission planning. Despite this growing dependence on software control and monitoring, there has been little to no consistent application of software safety practices and methodology to NASA's projects with safety critical software. Meanwhile, academia and private industry have been stepping forward with procedures and standards for safety critical systems and software, for example Dr. Nancy Leveson's book Safeware: System Safety and Computers. The NASA Software Safety Standard, originally published in 1997, was widely ignored due to its complexity and poor organization. It also focused on concepts rather than definite procedural requirements organized around a software project lifecycle. Led by NASA Headquarters Office of Safety and Mission Assurance, the NASA Software Safety Standard has recently undergone a significant update. This new standard provides the procedures and guidelines for evaluating a project for safety criticality and then lays out the minimum project lifecycle requirements to assure the software is created, operated, and maintained in the safest possible manner. This update of the standard clearly delineates the minimum set of software safety requirements for a project without detailing the implementation for those requirements. This allows the projects leeway to meet these requirements in many forms that best suit a particular project's needs and safety risk. In other words, it tells the project what to do, not how to do it. This update also incorporated advances in the state of the practice of software safety from academia and private industry. It addresses some of the more common issues now facing software developers in the NASA environment such as the use of Commercial-Off-the-Shelf Software (COTS), Modified OTS (MOTS), Government OTS (GOTS), and reused software. A team from across NASA developed the update and it has had both NASA-wide internal reviews by software engineering, quality, safety, and project management. It has also had expert external review. This presentation and paper will discuss the new NASA Software Safety Standard, its organization, and key features. It will start with a brief discussion of some NASA mission failures and incidents that had software as one of their root causes. It will then give a brief overview of the NASA Software Safety Process. This will include an overview of the key personnel responsibilities and functions that must be performed for safety-critical software.
[Comparison of port needle with safety device between Huber Plus (HP) and Poly PERF Safe (PPS)].
Shimono, Chigusa; Tanaka, Atsuko; Fujita, Ai; Ishimoto, Miki; Oura, Shoji; Yamaue, Hiroki; Sato, Morio
2010-05-01
An embedded port is frequently used for outpatients with advanced cancer in central venous chemotherapy or hepatic arterial chemoinfusion. The port needle with a safety device in an ambulatory treatment center is indispensable for medical employees and patient plus family to reduce the risk of a needle puncture accident and to prevent iatrogenic infection. The port needle with safety system has been already introduced in our chemotherapy center. There are two types of port needle with safety device; Huber Plus (HP, Medicon Co., Ltd.) and POLY PERF Safe (PPS, Pyolax Device, Co., Ltd.). The comparison of the feasibility between HP and PPS was conducted by both medical employees and patients plus family using an inquiry score method. HP was highly regarded for its stability plus fixation and PPS for its usefulness in puncture and extraction of the needle. PPS was found to be preferable to HP based on the overall evaluation.
NASA Technical Reports Server (NTRS)
Zhu, Dongming; Miller, Robert A.
2000-01-01
A steady-state laser heat flux technique has been developed at the NASA Glenn Research Center at Lewis Field to obtain critical thermal conductivity data of ceramic thermal barrier coatings under the temperature and thermal gradients that are realistically expected to be encountered in advanced engine systems. In this study, thermal conductivity change kinetics of a plasma-sprayed, 254-mm-thick ZrO2-8 wt % Y2O3 ceramic coating were obtained at high temperatures. During the testing, the temperature gradients across the coating system were carefully measured by the surface and back pyrometers and an embedded miniature thermocouple in the substrate. The actual heat flux passing through the coating system was determined from the metal substrate temperature drop (measured by the embedded miniature thermocouple and the back pyrometer) combined with one-dimensional heat transfer models.
System modeling with the DISC framework: evidence from safety-critical domains.
Reiman, Teemu; Pietikäinen, Elina; Oedewald, Pia; Gotcheva, Nadezhda
2012-01-01
The objective of this paper is to illustrate the development and application of the Design for Integrated Safety Culture (DISC) framework for system modeling by evaluating organizational potential for safety in nuclear and healthcare domains. The DISC framework includes criteria for good safety culture and a description of functions that the organization needs to implement in order to orient the organization toward the criteria. Three case studies will be used to illustrate the utilization of the DISC framework in practice.
Formalin-fixed paraffin-embedded (FFPE) samples provide a vast untapped resource for chemical safety and translational science. To date, genomic profiling of FFPE samples has been limited by poor RNA quality and inconsistent results with limited utility in dose-response assessmen...
Experimental criticality specifications. An annotated bibliography through 1977
DOE Office of Scientific and Technical Information (OSTI.GOV)
Paxton, H.C.
1978-05-01
The compilation of approximately 300 references gives sources of experimental criticality parameters of systems containing /sup 235/U, /sup 233/U, and /sup 239/Pu. The intent is to cover basic data for criticality safety applications. The references are arranged by subject.
Solar powered automobile automation for heatstroke prevention
NASA Astrophysics Data System (ADS)
Singh, Navtej Swaroop; Sharma, Ishan; Jangid, Santosh
2016-03-01
Heatstroke inside a car has been critical problem in every part of the world. Non-exertional heat stroke results from exposure to a high environmental temperature. Exertional heat stroke happens from strenuous exercise. This paper presents a solution for this fatal problem and proposes an embedded solution, which is cost effective and shows the feasibility in implementation. The proposed system consists of information sharing platform, interfacing of sensors, Global System Mobile (GSM), real time monitoring system and the system is powered by the solar panel. The system has been simulated and tested with experimental setup.
Critical Landau Velocity in Helium Nanodroplets
NASA Astrophysics Data System (ADS)
Brauer, Nils B.; Smolarek, Szymon; Loginov, Evgeniy; Mateo, David; Hernando, Alberto; Pi, Marti; Barranco, Manuel; Buma, Wybren J.; Drabbels, Marcel
2013-10-01
The best-known property of superfluid helium is the vanishing viscosity that objects experience while moving through the liquid with speeds below the so-called critical Landau velocity. This critical velocity is generally considered a macroscopic property as it is related to the collective excitations of the helium atoms in the liquid. In the present work we determine to what extent this concept can still be applied to nanometer-scale, finite size helium systems. To this end, atoms and molecules embedded in helium nanodroplets of various sizes are accelerated out of the droplets by means of optical excitation, and the speed distributions of the ejected particles are determined. The measurements reveal the existence of a critical velocity in these systems, even for nanodroplets consisting of only a thousand helium atoms. Accompanying theoretical simulations based on a time-dependent density functional description of the helium confirm and further elucidate this experimental finding.
Wetmore, Douglas; Goldberg, Andrew; Gandhi, Nishant; Spivack, John; McCormick, Patrick; DeMaria, Samuel
2016-10-01
Anaesthesiologists work in a high stress, high consequence environment in which missed steps in preparation may lead to medical errors and potential patient harm. The pre-anaesthetic induction period has been identified as a time in which medical errors can occur. The Anesthesia Patient Safety Foundation has developed a Pre-Anesthetic Induction Patient Safety (PIPS) checklist. We conducted this study to test the effectiveness of this checklist, when embedded in our institutional Anesthesia Information Management System (AIMS), on resident performance in a simulated environment. Using a randomised, controlled, observer-blinded design, we compared performance of anaesthesiology residents in a simulated operating room under production pressure using a checklist in completing a thorough pre-anaesthetic induction evaluation and setup with that of residents with no checklist. The checklist was embedded in the simulated operating room's electronic medical record. Data for 38 anaesthesiology residents shows a statistically significant difference in performance in pre-anaesthetic setup and evaluation as scored by blinded raters (maximum score 22 points), with the checklist group performing better by 7.8 points (p<0.01). The effects of gender and year of residency on total score were not significant. Simulation duration (time to anaesthetic agent administration) was increased significantly by the use of the checklist. Required use of a pre-induction checklist improves anaesthesiology resident performance in a simulated environment. The PIPS checklist as an integrated part of a departmental AIMS warrant further investigation as a quality measure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Software-Based Safety Systems in Space - Learning from other Domains
NASA Astrophysics Data System (ADS)
Klicker, M.; Putzer, H.
2012-01-01
Increasing complexity and new emerging capabilities for manned and unmanned missions have been the hallmark of the past decades of space exploration. One of the drivers in this process was the ever increasing use of software and software-intensive systems to implement system functions necessary to the capabilities needed. The course of technological evolution suggests that this development will continue well into the future with a number of challenges for the safety community some of which shall be discussed in this paper. The current state of the art reveals a number of problems with developing and assessing safety critical software which explains the reluctance of the space community to rely on software-based safety measures to mitigate hazards. Among others, usually lack of trustworthy evidence of software integrity in all foreseeable situations and the difficulties to integrate software in the traditional safety analysis framework are cited. Experience from other domains and recent developments in modern software development methodologies and verification techniques are analysed for the suitability for space systems and an avionics architectural framework (see STANAG 4626) for the implementation of safety critical software is proposed. This is shown to create among other features the possibility of numerous degradation modes enhancing overall system safety and interoperability of computerized space systems. It also potentially simplifies international cooperation on a technical level by introducing a higher degree of compatibility. As software safety cannot be tested or argued into a system in hindsight, the development process and especially the architecture chosen are essential to establish safety properties for the software used to implement safety functions. The core of the safety argument revolves around the separation of different functions and software modules from each other by minimal coupling of functions and credible separation mechanisms in the architecture combined with rigorous development methodologies for the software itself.
Acoustic emission safety monitoring of intermodal transportation infrastructure.
DOT National Transportation Integrated Search
2015-09-01
Safety and integrity of the national transportation infrastructure are of paramount importance and highway bridges are critical components of the highway system network. This network provides an immense contribution to the industry productivity and e...
Smoke Detection: Critical Element of a University Residential Fire Safety Program.
ERIC Educational Resources Information Center
Robinson, Donald A.
1979-01-01
A program at the University of Massachusetts/Amherst to assess the fire protection needs of its residential system is described. The study culminated in a multiphase fire safety improvement plan. (JMF)
1994-08-01
AGARD-AG-300 Vol. 12 04 ADVISORY GROUP FOR AEROSPACE RESEARCH & DEVELOPMENT 7 RUE ANCELLE, 92200 NEUILLY-SUR-SEINE, FRANCE AUG 0195 AGARDograph 300...AGARD Flight Test Techniques Series Volume 12 on The Principles of Flight Test Assessment of Flight-Safety-Critical Systems in Helicopters (Les...and Availability on Back Cover AGARD-AG-300 Vol. 12 ADVISORY GROUP FOR AEROSPACE RESEARCH & DEVELOPMENT 7 RUE ANCELLE, 92200 NEUILLY-SUR-SEINE, FRANCE
Evaluating Models of Human Performance: Safety-Critical Systems Applications
NASA Technical Reports Server (NTRS)
Feary, Michael S.
2012-01-01
This presentation is part of panel discussion on Evaluating Models of Human Performance. The purpose of this panel is to discuss the increasing use of models in the world today and specifically focus on how to describe and evaluate models of human performance. My presentation will focus on discussions of generating distributions of performance, and the evaluation of different strategies for humans performing tasks with mixed initiative (Human-Automation) systems. I will also discuss issues with how to provide Human Performance modeling data to support decisions on acceptability and tradeoffs in the design of safety critical systems. I will conclude with challenges for the future.
2018-01-01
Advanced driver assistance systems, ADAS, have shown the possibility to anticipate crash accidents and effectively assist road users in critical traffic situations. This is not the case for motorcyclists, in fact ADAS for motorcycles are still barely developed. Our aim was to study a camera-based sensor for the application of preventive safety in tilting vehicles. We identified two road conflict situations for which automotive remote sensors installed in a tilting vehicle are likely to fail in the identification of critical obstacles. Accordingly, we set two experiments conducted in real traffic conditions to test our stereo vision sensor. Our promising results support the application of this type of sensors for advanced motorcycle safety applications. PMID:29351267
System safety in Stirling engine development
NASA Technical Reports Server (NTRS)
Bankaitis, H.
1981-01-01
The DOE/NASA Stirling Engine Project Office has required that contractors make safety considerations an integral part of all phases of the Stirling engine development program. As an integral part of each engine design subtask, analyses are evolved to determine possible modes of failure. The accepted system safety analysis techniques (Fault Tree, FMEA, Hazards Analysis, etc.) are applied in various degrees of extent at the system, subsystem and component levels. The primary objectives are to identify critical failure areas, to enable removal of susceptibility to such failures or their effects from the system and to minimize risk.
Information Retrieval and Criticality in Parity-Time-Symmetric Systems
NASA Astrophysics Data System (ADS)
Kawabata, Kohei; Ashida, Yuto; Ueda, Masahito
2017-11-01
By investigating information flow between a general parity-time (P T -)symmetric non-Hermitian system and an environment, we find that the complete information retrieval from the environment can be achieved in the P T -unbroken phase, whereas no information can be retrieved in the P T -broken phase. The P T -transition point thus marks the reversible-irreversible criticality of information flow, around which many physical quantities such as the recurrence time and the distinguishability between quantum states exhibit power-law behavior. Moreover, by embedding a P T -symmetric system into a larger Hilbert space so that the entire system obeys unitary dynamics, we reveal that behind the information retrieval lies a hidden entangled partner protected by P T symmetry. Possible experimental situations are also discussed.
Threats to safety during sedation outside of the operating room and the death of Michael Jackson.
Webster, Craig S; Mason, Keira P; Shafer, Steven L
2016-03-01
From an understanding of human psychology and the reliability of high-technology systems, this review considers critical threats to the safety of patients undergoing sedation outside of the operating room, and will stratify these threats along what we define as the 'Patient Risk Continuum'. We then consider interventions suitable for addressing identified risks. The technology, organization and delivery of healthcare continue to become more complex, highlighting the importance of maintaining the safety of patients. Sedation outside of the operating room is known to be associated with higher rates of adverse events. However, a number of recent safety initiatives have shown benefit in improving patient safety. The following threats to patients undergoing sedation, in increasing order of risk, are discussed: equipment and environmental factors, known patient risks, poor team performance, combinatorial problems and egregious violations. To address these threats, we discuss a number of approaches consistent with the systems approach to safety, namely: encouraging functions, forcing functions, cognitive safety nets, information sharing, recovery strategies and regulatory change. Demonstrating improvement with any safety initiative relies critically on quality data collected on the problem area in question.
OSI for hardware/software interoperability
NASA Astrophysics Data System (ADS)
Wood, Richard J.; Harvey, Donald L.; Linderman, Richard W.; Gardener, Gary A.; Capraro, Gerard T.
1994-03-01
There is a need in public safety for real-time data collection and transmission from one or more sensors. The Rome Laboratory and the Ballistic Missile Defense Organization are pursuing an effort to bring the benefits of Open System Architectures (OSA) to embedded systems within the Department of Defense. When developed properly OSA provides interoperability, commonality, graceful upgradeability, survivability and hardware/software transportability to greatly minimize life cycle costs, integration and supportability. Architecture flexibility can be achieved to take advantage of commercial accomplishments by basing these developments on vendor-neutral commercially accepted standards and protocols.
Müller-Leonhardt, Alice; Mitchell, Shannon G; Vogt, Joachim; Schürmann, Tim
2014-07-01
In complex systems, such as hospitals or air traffic control operations, critical incidents (CIs) are unavoidable. These incidents can not only become critical for victims but also for professionals working at the "sharp end" who may have to deal with critical incident stress (CIS) reactions that may be severe and impede emotional, physical, cognitive and social functioning. These CIS reactions may occur not only under exceptional conditions but also during every-day work and become an important safety issue. In contrast to air traffic management (ATM) operations in Europe, which have readily adopted critical incident stress management (CISM), most hospitals have not yet implemented comprehensive peer support programs. This survey was conducted in 2010 at the only European general hospital setting which implemented CISM program since 2004. The aim of the article is to describe possible contribution of CISM in hospital settings framed from the perspective of organizational safety and individual health for healthcare professionals. Findings affirm that daily work related incidents also can become critical for healthcare professionals. Program efficiency appears to be influenced by the professional culture, as well as organizational structure and policies. Overall, findings demonstrate that the adaptation of the CISM program in general hospitals takes time but, once established, it may serve as a mechanism for changing professional culture, thereby permitting the framing of even small incidents or near misses as an opportunity to provide valuable feedback to the system. Copyright © 2014 Elsevier Ltd. All rights reserved.
Software Reliability Issues Concerning Large and Safety Critical Software Systems
NASA Technical Reports Server (NTRS)
Kamel, Khaled; Brown, Barbara
1996-01-01
This research was undertaken to provide NASA with a survey of state-of-the-art techniques using in industrial and academia to provide safe, reliable, and maintainable software to drive large systems. Such systems must match the complexity and strict safety requirements of NASA's shuttle system. In particular, the Launch Processing System (LPS) is being considered for replacement. The LPS is responsible for monitoring and commanding the shuttle during test, repair, and launch phases. NASA built this system in the 1970's using mostly hardware techniques to provide for increased reliability, but it did so often using custom-built equipment, which has not been able to keep up with current technologies. This report surveys the major techniques used in industry and academia to ensure reliability in large and critical computer systems.
NASA Technical Reports Server (NTRS)
Mackall, D. A.; Ishmael, S. D.; Regenie, V. A.
1983-01-01
Qualification considerations for assuring the safety of a life-critical digital flight control system include four major areas: systems interactions, verification, validation, and configuration control. The AFTI/F-16 design, development, and qualification illustrate these considerations. In this paper, qualification concepts, procedures, and methodologies are discussed and illustrated through specific examples.
Estimation of adhesive bond strength in laminated safety glass using guided mechanical waves
NASA Astrophysics Data System (ADS)
Huo, Shihong
Laminated safety glass is used in the automobile industry and in architectural applications. Laminated safety glass consists of a plastic interlayer, such as a layer of poly vinyl butyral (PVB) or Butacite, surrounded by two adjacent glass plates. The glass can be float glass, plate glass, tempered glass, or sheet glass, and the plastic interlayer is made of a viscoelastic material with relatively high damping. The level of adhesive bond strength between the plastic interlayer and the two adjacent glass plates has a significant role in the penetration resistance against flying objects and is a critical parameter towards ensuring the proper performance of safety glass. Therefore, estimation and control of adhesive bond levels in laminated safety glass is a critical issue. There are several destructive testing procedures used to quantify the adhesion level in laminated safety glass. These tests include the tension test, the peel test, the impact test, and the pummel test. All these tests have drawbacks including the pummel test method, which has been the most widely used in industry for over 80 years. The primary drawbacks of the pummel test method are that it is destructive and subjective (i.e., involves individual human judgment), which precludes this method for use as an on-line test method for quality control. Consequently, a quantitative nondestructive testing method to evaluate adhesion levels would be an asset to the laminated safety glass industry. In this study, adhesion levels in laminated safety glass samples, i.e., windshields, have been assessed using the guided mechanical wave method. To study the adhesive bond strength analytically, the imperfect interfaces between the plastic interlayer and the two adjacent glass plates in laminated safety glass are modeled using a bed of longitudinal and shear springs, and their stiffness characteristics are estimated using fracture mechanics and atomic force microscopy (AFM) surface measurements. The atomic force microscopy measurements are used to estimate the contact area at the imperfect interfaces between the plastic interlayer and the two adjacent glass plates for each of the laminates. The spring layers are then embedded in the global matrix method, which is used to predict the guided wave dispersion behavior of the laminated system. Based upon the guided wave energy velocity predictions for each of the laminates with different levels of adhesion, the S0 mode was selected as the most promising for use in nondestructively estimating adhesion levels in laminated safety glass. The predicted energy velocities (obtained using this multilayered model) were validated using guided wave energy velocity experimental measurements. The experimentally obtained velocity measurements are in good agreement with the predicted values. Guided wave attenuation in laminated safety glass is primarily due to the viscoelastic material properties of the PVB plastic interlayer. The attenuation properties of S1 mode were also explored to estimate the adhesive bond strength between the plastic interlayer and the two adjacent glass plates. Results show that the combination of both the energy velocity and attenuation methods has promise towards replacing the pummel test method to estimate the adhesion level in laminated safety glass.
Nuclear criticality safety: 5-day training course
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schlesser, J.A.
1992-11-01
This compilation of notes is presented as a source reference for the criticality safety course. It represents the contributions of many people, particularly Tom McLaughlin, the course's primary instructor. At the completion of this training course, the attendee will: be able to define terms commonly used in nuclear criticality safety; be able to appreciate the fundamentals of nuclear criticality safety; be able to identify factors which affect nuclear criticality safety; be able to identify examples of criticality controls as used at Los Alamos; be able to identify examples of circumstances present during criticality accidents; be able to identify examples ofmore » computer codes used by the nuclear criticality safety specialist; be able to identify examples of safety consciousness required in nuclear criticality safety.« less
ISHM Implementation for Constellation Systems
NASA Technical Reports Server (NTRS)
Figueroa, Fernando; Holland, Randy; Schmalzel, John; Duncavage, Dan; Crocker, Alan; Alena, Rick
2006-01-01
Integrated System Health Management (ISHM) is a capability that focuses on determining the condition (health) of every element in a complex System (detect anomalies, diagnose causes, prognosis of future anomalies), and provide data, information, and knowledge (DIaK) "not just data" to control systems for safe and effective operation. This capability is currently done by large teams of people, primarily from ground, but needs to be embedded on-board systems to a higher degree to enable NASA's new Exploration Mission (long term travel and stay in space), while increasing safety and decreasing life cycle costs of systems (vehicles; platforms; bases or outposts; and ground test, launch, and processing operations). This viewgraph presentation reviews the use of ISHM for the Constellation system.
Kuo, Calvin C; Robb, William J
2013-06-01
The prevention of medical and surgical harm remains an important public health problem despite increased awareness and implementation of safety programs. Successful introduction and maintenance of surgical safety programs require both surgeon leadership and collaborative surgeon-hospital alignment. Documentation of success of such surgical safety programs in orthopaedic practice is limited. We describe the scope of orthopaedic surgical patient safety issues, define critical elements of orthopaedic surgical safety, and outline leadership roles for orthopaedic surgeons needed to establish and sustain a culture of safety in contemporary healthcare systems. We identified the most common causes of preventable surgical harm based on adverse and sentinel surgical events reported to The Joint Commission. A comprehensive literature review through a MEDLINE(®) database search (January 1982 through April 2012) to identify pertinent orthopaedic surgical safety articles found 14 articles. Where gaps in orthopaedic literature were identified, the review was supplemented by 22 nonorthopaedic surgical references. Our final review included 36 articles. Six important surgical safety program elements needed to eliminate preventable surgical harm were identified: (1) effective surgical team communication, (2) proper informed consent, (3) implementation and regular use of surgical checklists, (4) proper surgical site/procedure identification, (5) reduction of surgical team distractions, and (6) routine surgical data collection and analysis to improve the safety and quality of surgical patient care. Successful surgical safety programs require a culture of safety supported by all six key surgical safety program elements, active surgeon champions, and collaborative hospital and/or administrative support designed to enhance surgical safety and improve surgical patient outcomes. Further research measuring improvements from such surgical safety systems in orthopaedic care is needed.
Bayesian Statistics and Uncertainty Quantification for Safety Boundary Analysis in Complex Systems
NASA Technical Reports Server (NTRS)
He, Yuning; Davies, Misty Dawn
2014-01-01
The analysis of a safety-critical system often requires detailed knowledge of safe regions and their highdimensional non-linear boundaries. We present a statistical approach to iteratively detect and characterize the boundaries, which are provided as parameterized shape candidates. Using methods from uncertainty quantification and active learning, we incrementally construct a statistical model from only few simulation runs and obtain statistically sound estimates of the shape parameters for safety boundaries.
NASA Astrophysics Data System (ADS)
Malyshev, Mikhail; Kreimer, Johannes
2013-09-01
Safety analyses for electrical, electronic and/or programmable electronic (E/E/EP) safety-related systems used in payload applications on-board the International Space Station (ISS) are often based on failure modes, effects and criticality analysis (FMECA). For industrial applications of E/E/EP safety-related systems, comparable strategies exist and are defined in the IEC-61508 standard. This standard defines some quantitative criteria based on potential failure modes (for example, Safe Failure Fraction). These criteria can be calculated for an E/E/EP system or components to assess their compliance to requirements of a particular Safety Integrity Level (SIL). The standard defines several SILs depending on how much risk has to be mitigated by a safety-critical system. When a FMECA is available for an ISS payload or its subsystem, it may be possible to calculate the same or similar parameters as defined in the 61508 standard. One example of a payload that has a dedicated functional safety subsystem is the Electromagnetic Levitator (EML). This payload for the ISS is planned to be operated on-board starting 2014. The EML is a high-temperature materials processing facility. The dedicated subsystem "Hazard Control Electronics" (HCE) is implemented to ensure compliance to failure tolerance in limiting samples processing parameters to maintain generation of the potentially toxic by-products to safe limits in line with the requirements applied to the payloads by the ISS Program. The objective of this paper is to assess the implementation of the HCE in the EML against criteria for functional safety systems in the IEC-61508 standard and to evaluate commonalities and differences with respect to safety requirements levied on ISS Payloads. An attempt is made to assess a possibility of using commercially available components and systems certified for compliance to industrial functional safety standards in ISS payloads.
Tiger Team Assessment of the Los Alamos National Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-11-01
The purpose of the safety and health assessment was to determine the effectiveness of representative safety and health programs at the Los Alamos National Laboratory (LANL). Within the safety and health programs at LANL, performance was assessed in the following technical areas: Organization and Administration, Quality Verification, Operations, Maintenance, Training and Certification, Auxiliary Systems, Emergency Preparedness, Technical Support, Packaging and Transportation, Nuclear Criticality Safety, Security/Safety Interface, Experimental Activities, Site/Facility Safety Review, Radiological Protection, Personnel Protection, Worker Safety and Health (OSHA) Compliance, Fire Protection, Aviation Safety, Explosives Safety, Natural Phenomena, and Medical Services.
How does information congruence influence diagnosis performance?
Chen, Kejin; Li, Zhizhong
2015-01-01
Diagnosis performance is critical for the safety of high-consequence industrial systems. It depends highly on the information provided, perceived, interpreted and integrated by operators. This article examines the influence of information congruence (congruent information vs. conflicting information vs. missing information) and its interaction with time pressure (high vs. low) on diagnosis performance on a simulated platform. The experimental results reveal that the participants confronted with conflicting information spent significantly more time generating correct hypotheses and rated the results with lower probability values than when confronted with the other two levels of information congruence and were more prone to arrive at a wrong diagnosis result than when they were provided with congruent information. This finding stresses the importance of the proper processing of non-congruent information in safety-critical systems. Time pressure significantly influenced display switching frequency and completion time. This result indicates the decisive role of time pressure. Practitioner Summary: This article examines the influence of information congruence and its interaction with time pressure on human diagnosis performance on a simulated platform. For complex systems in the process control industry, the results stress the importance of the proper processing of non-congruent information in safety-critical systems.
Edwards, Brian; Hugman, Bruce; Tobin, Mary; Whalen, Matthew
2012-04-01
Robust, active cooperation, and effective, open communication between all stakeholders is essential for ensuring regulatory compliance and healthcare product safety; avoiding the necessity for whistle-blowing; and, most essentially, meeting the transparency requirements of public trust.The focus here is on what can be done within a healthcare product organization (HPO) to achieve actionable, sustainable policies and practices such as leadership, management, and supervision role-modelling of best practice; ongoing process review and improvements in every department; protection of those who report concerns through robust policies endorsed at Board level throughout an organization to eliminate the fear of retaliation; training in open, non-defensive team-working principles; and mediation structure and process for resolution of differences of opinion or interpretation of contradictory and volatile data.Based on analyses of other safety systems, workplace silence and interpersonal breakdowns are warning signs of defective systems underlying poor compliance and compromising safety. Remedying the situation requires attention to the root causes underlying such symptoms of dysfunction, especially the human factor, i.e. those factors that influence human performance. It is essential that leadership and management listen to employees' concerns about systems and processes, assess them impartially and reward contributions that improve safety.Fundamentally, the safety, transparency, and trustworthiness of HPOs, both commercial and regulatory, can be judged by the extent of the freedom of their staff to 'speak up' when the time is right. This, in turn, consolidates the trust of external stakeholders in the safety of a system and its products. The promotion of 'speaking up' in an organization provides an important safeguard against the risk of poor compliance and the undermining of societal confidence in the safety of healthcare products.
ERIC Educational Resources Information Center
Bliquez, Rebecca; Deeken, Lynn
2016-01-01
Professional development is critically important for librarians trying to establish an embedded presence in online and hybrid courses. The institutional learning management system (LMS) provides a medium for enhanced visibility of both library resources and librarians as instructional collaborators and curriculum designers. This case study…
V&V Within Reuse-Based Software Engineering
NASA Technical Reports Server (NTRS)
Addy, Edward A.
1996-01-01
Verification and Validation (V&V) is used to increase the level of assurance of critical software, particularly that of safety-critical and mission-critical software. V&V is a systems engineering discipline that evaluates the software in a systems context, and is currently applied during the development of a specific application system. In order to bring the effectiveness of V&V to bear within reuse-based software engineering, V&V must be incorporated within the domain engineering process.
Critical and Alternative Directions in Applied Linguistics
ERIC Educational Resources Information Center
Pennycook, Alastair
2010-01-01
Critical directions in applied linguistics can be understood in various ways. The term "critical" as it has been used in "critical applied linguistics," "critical discourse analysis," "critical literacy" and so forth, is now embedded as part of applied linguistic work, adding an overt focus on questions of power and inequality to discourse…
Certification Processes for Safety-Critical and Mission-Critical Aerospace Software
NASA Technical Reports Server (NTRS)
Nelson, Stacy
2003-01-01
This document is a quick reference guide with an overview of the processes required to certify safety-critical and mission-critical flight software at selected NASA centers and the FAA. Researchers and software developers can use this guide to jumpstart their understanding of how to get new or enhanced software onboard an aircraft or spacecraft. The introduction contains aerospace industry definitions of safety and safety-critical software, as well as, the current rationale for certification of safety-critical software. The Standards for Safety-Critical Aerospace Software section lists and describes current standards including NASA standards and RTCA DO-178B. The Mission-Critical versus Safety-Critical software section explains the difference between two important classes of software: safety-critical software involving the potential for loss of life due to software failure and mission-critical software involving the potential for aborting a mission due to software failure. The DO-178B Safety-critical Certification Requirements section describes special processes and methods required to obtain a safety-critical certification for aerospace software flying on vehicles under auspices of the FAA. The final two sections give an overview of the certification process used at Dryden Flight Research Center and the approval process at the Jet Propulsion Lab (JPL).
NASA Astrophysics Data System (ADS)
Chalioris, Constantin E.; Papadopoulos, Nikos A.; Angeli, Georgia M.; Karayannis, Chris G.; Liolios, Asterios A.; Providakis, Costas P.
2015-10-01
Damage detection at early cracking stages in shear-critical reinforced concrete beams, before further deterioration and their inevitable brittle shear failure is crucial for structural safety and integrity. The effectiveness of a structural health monitoring technique using the admittance measurements of piezoelectric transducers mounted on a reinforced concrete beam without shear reinforcement is experimentally investigated. Embedded "smart aggregate" transducers and externally bonded piezoelectric patches have been placed in arrays at both shear spans of the beam. Beam were tested till total shear failure and monitored at three different states; healthy, flexural cracking and diagonal cracking. Test results showed that transducers close to the critical diagonal crack provided sound and graduated discrepancies between the admittance responses at the healthy state and thedamage levels.Damage assessment using statistical indices calculated from the measurements of all transducers was also attempted. Rational changes of the index values were obtained with respect to the increase of the damage. Admittance responses and index values of the transducers located on the shear span where the critical diagonal crack formed provided cogent evidence of damage. On the contrary, negligible indication of damage was yielded by the responses of the transducers located on the other shear span, where no diagonal cracking occurred.
Implementing Embedded Training (ET): Volume 4. Identifying ET Requirements
1988-11-01
procedures that support the effective co::sidet·;,tion, definition, development , and integration of e::1 11cddcd trzd;Li:1r; (ET) ;~.:1p:1bilities...an effective ET compo- nent would be impossible or have undesired schedule or cost impacts. Iteration Two: Early System Development Once the new...ET. These needs can sometimes have a significant effect on the design of the prime item system. It is critical that materiel developers be made aware
2007-01-15
it can detect specifically proscribed content changes to critical files (e.g., illegal shells inserted into /etc/ passwd ). Fourth, it can detect the...UNIX password management involves a pair of inter-related files (/etc/ passwd and /etc/shadow). The corresponding access patterns seen at the storage...content integrity verification is utilized. As a concrete example, consider a UNIX system password file (/etc/ passwd ), which consists of a set of well
ERIC Educational Resources Information Center
Almeida, Renita A.; Dickinson, J. Edwin; Maybery, Murray T.; Badcock, Johanna C.; Badcock, David R.
2010-01-01
The Embedded Figure Test (EFT) requires locating a simple shape embedded within a background of overlapping target-irrelevant scene elements. Observers with autism, or those with high levels of autistic-like traits, typically outperform matched comparison groups on the EFT. This research investigated the critical visual properties which give rise…
Using Smart Pumps to Understand and Evaluate Clinician Practice Patterns to Ensure Patient Safety
Mansfield, Jennifer; Jarrett, Steven
2013-01-01
Background: Safety software installed on intravenous (IV) infusion pumps has been shown to positively impact the quality of patient care through avoidance of medication errors. The data derived from the use of smart pumps are often overlooked, although these data provide helpful insight into the delivery of quality patient care. Objective: The objectives of this report are to describe the value of implementing IV infusion safety software and analyzing the data and reports generated by this system. Case study: Based on experience at the Carolinas HealthCare System (CHS), executive score cards provide an aggregate view of compliance rate, number of alerts, overrides, and edits. The report of serious errors averted (ie, critical catches) supplies the location, date, and time of the critical catch, thereby enabling management to pinpoint the end-user for educational purposes. By examining the number of critical catches, a return on investment may be calculated. Assuming 3,328 of these events each year, an estimated cost avoidance would be $29,120,000 per year for CHS. Other reports allow benchmarking between institutions. Conclusion: A review of the data about medication safety across CHS has helped garner support for a medication safety officer position with the goal of ultimately creating a safer environment for the patient. PMID:24474836
Mission and Safety Critical (MASC) plans for the MASC Kernel simulation
NASA Technical Reports Server (NTRS)
1991-01-01
This report discusses a prototype for Mission and Safety Critical (MASC) kernel simulation which explains the intended approach and how the simulation will be used. Smalltalk is chosen for the simulation because of usefulness in quickly building working models of the systems and its object-oriented approach to software. A scenario is also introduced to give details about how the simulation works. The eventual system will be a fully object-oriented one implemented in Ada via Dragoon. To implement the simulation, a scenario using elements typical of those in the Space Station, was created.
Improving patient safety: lessons from rock climbing.
Robertson, Nic
2012-02-01
How to improve patient safety remains an intractable problem, despite large investment and some successes. Academics have argued that the root of the problem is a lack of a comprehensive 'safety culture' in hospitals. Other safety-critical industries such as commercial aviation invest heavily in staff training to develop such a culture, but comparable programmes are almost entirely absent from the health care sector. In rock climbing and many other dangerous activities, the 'buddy system' is used to ensure that safety systems are adhered to despite adverse circumstances. This system involves two or more people using simple checks and clear communication to prevent problems causing harm. Using this system as an example could provide a simple, original and entertaining way of introducing medical students to the idea that human factors are central to ensuring patient safety. Teaching the buddy system may improve understanding and acceptance of other patient safety initiatives, and could also be used by junior doctors as a tool to improve the safety of their practice. © Blackwell Publishing Ltd 2012.
Integrated Systems Health Management for Space Exploration
NASA Technical Reports Server (NTRS)
Uckun, Serdar
2005-01-01
Integrated Systems Health Management (ISHM) is a system engineering discipline that addresses the design, development, operation, and lifecycle management of components, subsystems, vehicles, and other operational systems with the purpose of maintaining nominal system behavior and function and assuring mission safety and effectiveness under off-nominal conditions. NASA missions are often conducted in extreme, unfamiliar environments of space, using unique experimental spacecraft. In these environments, off-nominal conditions can develop with the potential to rapidly escalate into mission- or life-threatening situations. Further, the high visibility of NASA missions means they are always characterized by extraordinary attention to safety. ISHM is a critical element of risk mitigation, mission safety, and mission assurance for exploration. ISHM enables: In-space maintenance and repair; a) Autonomous (and automated) launch abort and crew escape capability; b) Efficient testing and checkout of ground and flight systems; c) Monitoring and trending of ground and flight system operations and performance; d) Enhanced situational awareness and control for ground personnel and crew; e) Vehicle autonomy (self-sufficiency) in responding to off-nominal conditions during long-duration and distant exploration missions; f) In-space maintenance and repair; and g) Efficient ground processing of reusable systems. ISHM concepts and technologies may be applied to any complex engineered system such as transportation systems, orbital or planetary habitats, observatories, command and control systems, life support systems, safety-critical software, and even the health of flight crews. As an overarching design and operational principle implemented at the system-of-systems level, ISHM holds substantial promise in terms of affordability, safety, reliability, and effectiveness of space exploration missions.
NASA Astrophysics Data System (ADS)
Shahriari, D.; Zolfaghari, A.; Masoumi, F.
2011-01-01
Nondestructive evaluation is explained as nondestructive testing, nondestructive inspection, and nondestructive examination. It is a desire to determine some characteristic of the object or to determine whether the object contains irregularities, discontinuities, or flaws. Ultrasound based inspection techniques are used extensively throughout industry for detection of flaws in engineering materials. The range and variety of imperfections encountered is large, and critical assessment of location, size, orientation and type is often difficult. In addition, increasing quality requirements of new standards and codes of practice relating to fitness for purpose are placing higher demands on operators. Applying of an expert knowledge-based analysis in ultrasonic examination is a powerful tool that can help assure safety, quality, and reliability; increase productivity; decrease liability; and save money. In this research, an expert module system is coupled with ultrasonic examination (A-Scan Procedure) to determine and evaluate type and location of flaws that embedded during welding parts. The processing module of this expert system is implemented based on EN standard to classify welding defects, acceptance condition and measuring of their location via echo static pattern and image processing. The designed module introduces new system that can automate evaluating of the results of A-scan method according to EN standard. It can simultaneously recognize the number and type of defects, and determine flaw position during each scan.
Flight control system design factors for applying automated testing techniques
NASA Technical Reports Server (NTRS)
Sitz, Joel R.; Vernon, Todd H.
1990-01-01
Automated validation of flight-critical embedded systems is being done at ARC Dryden Flight Research Facility. The automated testing techniques are being used to perform closed-loop validation of man-rated flight control systems. The principal design features and operational experiences of the X-29 forward-swept-wing aircraft and F-18 High Alpha Research Vehicle (HARV) automated test systems are discussed. Operationally applying automated testing techniques has accentuated flight control system features that either help or hinder the application of these techniques. The paper also discusses flight control system features which foster the use of automated testing techniques.
McEwan, Thomas E.
1997-01-01
A safety device includes a wire loop embedded in the glass of a passenger car window and routed near the closing leading-edge of the window. The wire loop carries microwave pulses around the loop to and from a transceiver with separate output and input ports. An evanescent field only and inch or two in radius is created along the wire loop by the pulses. Just about any object coming within the evanescent field will dramatically reduce the energy of the microwave pulses received back by the transceiver. Such a loss in energy is interpreted as a closing area blockage, and electrical interlocks are provided to halt or reverse a power window motor that is actively trying to close the window.
McEwan, T.E.
1997-08-26
A safety device includes a wire loop embedded in the glass of a passenger car window and routed near the closing leading-edge of the window. The wire loop carries microwave pulses around the loop to and from a transceiver with separate output and input ports. An evanescent field only an inch or two in radius is created along the wire loop by the pulses. Just about any object coming within the evanescent field will dramatically reduce the energy of the microwave pulses received back by the transceiver. Such a loss in energy is interpreted as a closing area blockage, and electrical interlocks are provided to halt or reverse a power window motor that is actively trying to close the window. 5 figs.
Safety management system needs assessment.
DOT National Transportation Integrated Search
2016-04-01
The safety of the traveling public is critical as each year there are approximately 200 highway fatalities in Nebraska and numerous crash injuries. The objective of this research was to conduct a needs assessment to identify the requirements of a sta...
Improved Testing Capability and Adaptability Through the Use of Wireless Sensors
NASA Technical Reports Server (NTRS)
Solano, Wanda M.
2003-01-01
From the first Saturn V rocket booster (S-II-T) testing in 1966 and the routine Space Shuttle Main Engine (SSME) testing beginning in 1975, to more recent test programs such as the X-33 Aerospike Engine, the Integrated Powerhead Development (IPD) program, and the Hybrid Sounding Rocket (HYSR), Stennis Space Center (SSC) continues to be a premier location for conducting large-scale testing. Central to each test program is the capability for sensor systems to deliver reliable measurements and high quality data, while also providing a means to monitor the test stand area to the highest degree of safety and sustainability. Sensor wiring is routed along piping and through cable trenches, making its way from the engine test area, through the test stand area and to the signal conditioning building before final transfer to the test control center. When sensor requirements lie outside the reach of the routine sensor cable routing, the use of wireless sensor networks becomes particularly attractive due to their versatility and ease of installation. As part of an on-going effort to enhance the testing capabilities of Stennis Space Center, the Test Technology and Development group has found numerous applications for its sensor-adaptable wireless sensor suite. While not intended for critical engine measurements or control loops, in-house hardware and software development of the sensor suite can provide improved testing capability for a range of applications including the safety monitoring of propellant storage barrels and as an experimental test-bed for embedded health monitoring paradigms.
Commercial grade item (CGI) dedication of MDR relays for nuclear safety related applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Das, R.K.; Julka, A.; Modi, G.
1994-08-01
MDR relays manufactured by Potter and Brumfield (P and B) have been used in various safety related applications in commercial nuclear power plants. These include emergency safety features (ESF) actuation systems, emergency core cooling systems (ECCS) actuation, and reactor protection systems. The MDR relays manufactured prior to May 1990 showed signs of generic failure due to corrosion and outgassing of coil varnish. P and B has made design changes to correct these problems in relays manufactured after May 1990. However, P and B does not manufacture the relays under any 10CFR50 Appendix B quality assurance (QA) program. They manufacture themore » relays under their commercial QA program and supply these as commercial grade items. This necessitates CGI Dedication of these relays for use in nuclear-safety-related applications. This paper presents a CGI dedication program that has been used to dedicate the MDR relays manufactured after May 1990. The program is in compliance with current Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) guidelines and applicable industry standards; it specifies the critical characteristics of the relays, provides the tests and analysis required to verify the critical characteristics, the acceptance criteria for the test results, performs source verification to qualify P and B for its control of the critical characteristics, and provides documentation. The program provides reasonable assurance that the new MDR relays will perform their intended safety functions.« less
NASA Technical Reports Server (NTRS)
Torres-Pomales, Wilfredo
2014-01-01
This report presents an example of the application of multi-criteria decision analysis to the selection of an architecture for a safety-critical distributed computer system. The design problem includes constraints on minimum system availability and integrity, and the decision is based on the optimal balance of power, weight and cost. The analysis process includes the generation of alternative architectures, evaluation of individual decision criteria, and the selection of an alternative based on overall value. In this example presented here, iterative application of the quantitative evaluation process made it possible to deliberately generate an alternative architecture that is superior to all others regardless of the relative importance of cost.
Patient Safety Learning Systems: A Systematic Review and Qualitative Synthesis.
2017-01-01
A patient safety learning system (sometimes called a critical incident reporting system) refers to structured reporting, collation, and analysis of critical incidents. To inform a provincial working group's recommendations for an Ontario Patient Safety Event Learning System, a systematic review was undertaken to determine design features that would optimize its adoption into the health care system and would inform implementation strategies. The objective of this review was to address two research questions: (a) what are the barriers to and facilitators of successful adoption of a patient safety learning system reported by health professionals and (b) what design components maximize successful adoption and implementation? To answer the first question, we used a published systematic review. To answer the second question, we used scoping study methodology. Common barriers reported in the literature by health care professionals included fear of blame, legal penalties, the perception that incident reporting does not improve patient safety, lack of organizational support, inadequate feedback, lack of knowledge about incident reporting systems, and lack of understanding about what constitutes an error. Common facilitators included a non-accusatory environment, the perception that incident reporting improves safety, clarification of the route of reporting and of how the system uses reports, enhanced feedback, role models (such as managers) using and promoting reporting, legislated protection of those who report, ability to report anonymously, education and training opportunities, and clear guidelines on what to report. Components of a patient safety learning system that increased successful adoption and implementation were emphasis on a blame-free culture that encourages reporting and learning, clear guidelines on how and what to report, making sure the system is user-friendly, organizational development support for data analysis to generate meaningful learning outcomes, and multiple mechanisms to provide feedback through routes to reporters and the wider community (local meetings, email alerts, bulletins, paper contributions, etc.). The design of a patient safety learning system can be optimized by an awareness of the barriers to and facilitators of successful adoption and implementation identified by health care professionals. Evaluation of the effectiveness of a patient safety learning system is needed to refine its design.
NASA Astrophysics Data System (ADS)
Lv, Zhong; Chen, Huisu
2014-10-01
Autonomous healing of cracks using pre-embedded capsules containing healing agent is becoming a promising approach to restore the strength of damaged structures. In addition to the material properties, the size and volume fraction of capsules influence crack healing in the matrix. Understanding the crack and capsule interaction is critical in the development and design of structures made of self-healing materials. Assuming that the pre-embedded capsules are randomly dispersed we theoretically model flat ellipsoidal crack interaction with capsules and determine the probability of a crack intersecting the pre-embedded capsules i.e. the self-healing probability. We also develop a probabilistic model of a crack simultaneously meeting with capsules and catalyst carriers in two-component self-healing system matrix. Using a risk-based healing approach, we determine the volume fraction and size of the pre-embedded capsules that are required to achieve a certain self-healing probability. To understand the effect of the shape of the capsules on self-healing we theoretically modeled crack interaction with spherical and cylindrical capsules. We compared the results of our theoretical model with Monte-Carlo simulations of crack interaction with capsules. The formulae presented in this paper will provide guidelines for engineers working with self-healing structures in material selection and sustenance.
Wireless and embedded carbon nanotube networks for damage detection in concrete structures
NASA Astrophysics Data System (ADS)
Saafi, Mohamed
2009-09-01
Concrete structures undergo an uncontrollable damage process manifesting in the form of cracks due to the coupling of fatigue loading and environmental effects. In order to achieve long-term durability and performance, continuous health monitoring systems are needed to make critical decisions regarding operation, maintenance and repairs. Recent advances in nanostructured materials such as carbon nanotubes have opened the door for new smart and advanced sensing materials that could effectively be used in health monitoring of structures where wireless and real time sensing could provide information on damage development. In this paper, carbon nanotube networks were embedded into a cement matrix to develop an in situ wireless and embedded sensor for damage detection in concrete structures. By wirelessly measuring the change in the electrical resistance of the carbon nanotube networks, the progress of damage can be detected and monitored. As a proof of concept, wireless cement-carbon nanotube sensors were embedded into concrete beams and subjected to monotonic and cyclic loading to evaluate the effect of damage on their response. Experimental results showed that the wireless response of the embedded nanotube sensors changes due to the formation of cracks during loading. In addition, the nanotube sensors were able to detect the initiation of damage at an early stage of loading.
Future Data Communication Architectures for Safety Critical Aircraft Cabin Systems
NASA Astrophysics Data System (ADS)
Berkhahn, Sven-Olaf
2012-05-01
The cabin of modern aircraft is subject to increasing demands for fast reconfiguration and hence flexibility. These demands require studies for new network architectures and technologies of the electronic cabin systems, which consider also weight and cost reductions as well as safety constraints. Two major approaches are in consideration to reduce the complex and heavy wiring harness: the usage of a so called hybrid data bus technology, which enables the common usage of the same data bus for several electronic cabin systems with different safety and security requirements and the application of wireless data transfer technologies for electronic cabin systems.
Russ, Alissa L; Jahn, Michelle A; Patel, Himalaya; Porter, Brian W; Nguyen, Khoa A; Zillich, Alan J; Linsky, Amy; Simon, Steven R
2018-06-01
An electronic medication reconciliation tool was previously developed by another research team to aid provider-patient communication for medication reconciliation. To evaluate the usability of this tool, we integrated artificial safety probes into standard usability methods. The objective of this article is to describe this method of using safety probes, which enabled us to evaluate how well the tool supports users' detection of medication discrepancies. We completed a mixed-method usability evaluation in a simulated setting with 30 participants: 20 healthcare professionals (HCPs) and 10 patients. We used factual scenarios but embedded three artificial safety probes: (1) a missing medication (i.e., omission); (2) an extraneous medication (i.e., commission); and (3) an inaccurate dose (i.e., dose discrepancy). We measured users' detection of each probe to estimate the probability that a HCP or patient would detect these discrepancies. Additionally, we recorded participants' detection of naturally occurring discrepancies. Each safety probe was detected by ≤50% of HCPs. Patients' detection rates were generally higher. Estimates indicate that a HCP and patient, together, would detect 44.8% of these medication discrepancies. Additionally, HCPs and patients detected 25 and 45 naturally-occurring discrepancies, respectively. Overall, detection of medication discrepancies was low. Findings indicate that more advanced interface designs are warranted. Future research is needed on how technologies can be designed to better aid HCPs' and patients' detection of medication discrepancies. This is one of the first studies to evaluate the usability of a collaborative medication reconciliation tool and assess HCPs' and patients' detection of medication discrepancies. Results demonstrate that embedded safety probes can enhance standard usability methods by measuring additional, clinically-focused usability outcomes. The novel safety probes we used may serve as an initial, standard set for future medication reconciliation research. More prevalent use of safety probes could strengthen usability research for a variety of health information technologies. Published by Elsevier Inc.
Ten Recommendations for a Safer School Year. Safety Spotlight
ERIC Educational Resources Information Center
Love, Tyler S.; Roy, Ken R.
2017-01-01
The beginning of a new school year can be hectic, but it is an opportune and critical time for teachers, supervisors, administrators, and school systems to establish proper safety procedures and practices. It can be more difficult to correct inappropriate behaviors or unsafe habits later in the year. This is especially true if a safety accident…
The application of polyethylene glycol (PEG) to electron microscopy
1980-01-01
The cytoplasm of cells from a variety of tissues has been viewed in sections (0.25-1 micrometers) devoid of any embedding resin. Glutaraldehyde- and osmium tetroxide-fixed tissues were infiltrated and embedded in a water-miscible wax, polyethylene glycol (PEG), and subsequently sectioned on dry glass or diamond knives. The PEG matrix was removed and the sections were placed on Formvarcarbon-polylysine- coated grids, dehydrated, dried by the critical-point method, and observed in either the high- or low-voltage electron microscope. Stereoscopic views of cells devoid of embedding resin present an image of cell utrastructure unobscured by electron-scattering resins similar to the image of whole, unembedded critical-point-dried or freeze-dried cultured cells observed by transmission electron microscopy. All organelles, including the cytoskeletal structures, are identified and appear not to have been damaged during processing, although membrane components appear somewhat less distinct. The absence of an embedding matrix eliminates the need for additional staining to increase contrast, unlike the situation with specimens embedded in standard electron-scattering resins. The PEG technique thus appears to be a valuable adjunct to conventional methods for ultrastructural analysis. PMID:7400222
The application of polyethylene glycol (PEG) to electron microscopy.
Wolosewick, J J
1980-08-01
The cytoplasm of cells from a variety of tissues has been viewed in sections (0.25-1 micrometers) devoid of any embedding resin. Glutaraldehyde- and osmium tetroxide-fixed tissues were infiltrated and embedded in a water-miscible wax, polyethylene glycol (PEG), and subsequently sectioned on dry glass or diamond knives. The PEG matrix was removed and the sections were placed on Formvarcarbon-polylysine-coated grids, dehydrated, dried by the critical-point method, and observed in either the high- or low-voltage electron microscope. Stereoscopic views of cells devoid of embedding resin present an image of cell utrastructure unobscured by electron-scattering resins similar to the image of whole, unembedded critical-point-dried or freeze-dried cultured cells observed by transmission electron microscopy. All organelles, including the cytoskeletal structures, are identified and appear not to have been damaged during processing, although membrane components appear somewhat less distinct. The absence of an embedding matrix eliminates the need for additional staining to increase contrast, unlike the situation with specimens embedded in standard electron-scattering resins. The PEG technique thus appears to be a valuable adjunct to conventional methods for ultrastructural analysis.
The changing paradigm in surgery is system integration: How do we respond?
Zenilman, Michael E; Freischlag, Julie-Ann
2017-12-08
With expansion of health care systems across the country, close relationships need to be developed between academic medical centers and their affiliated community hospitals. This creates opportunity to integrate surgical programs across different hospitals. Herein we describe a model of surgical integration at the system level of five large hospitals. We discuss utilizing advantages that both the academic and community hospital bring to the model. A close relationship between an interdisciplinary team, which includes the academic surgical chair, a regional director liaison who was embedded in the community, individual hospital leadership, and practice plan leaders was created. Three pillars as a foundation to success were physician leadership, the use of system infrastructure and development of new processes. This resulted in development of trust, leading to successful recruitments, models of employment and expansion into novel areas of patient safety. Once created, new opportunities for programming for surgical safety across the health care were identified. Copyright © 2017 Elsevier Inc. All rights reserved.
Ross, Joseph S; Bates, Jonathan; Parzynski, Craig S; Akar, Joseph G; Curtis, Jeptha P; Desai, Nihar R; Freeman, James V; Gamble, Ginger M; Kuntz, Richard; Li, Shu-Xia; Marinac-Dabic, Danica; Masoudi, Frederick A; Normand, Sharon-Lise T; Ranasinghe, Isuru; Shaw, Richard E; Krumholz, Harlan M
2017-01-01
Machine learning methods may complement traditional analytic methods for medical device surveillance. Using data from the National Cardiovascular Data Registry for implantable cardioverter-defibrillators (ICDs) linked to Medicare administrative claims for longitudinal follow-up, we applied three statistical approaches to safety-signal detection for commonly used dual-chamber ICDs that used two propensity score (PS) models: one specified by subject-matter experts (PS-SME), and the other one by machine learning-based selection (PS-ML). The first approach used PS-SME and cumulative incidence (time-to-event), the second approach used PS-SME and cumulative risk (Data Extraction and Longitudinal Trend Analysis [DELTA]), and the third approach used PS-ML and cumulative risk (embedded feature selection). Safety-signal surveillance was conducted for eleven dual-chamber ICD models implanted at least 2,000 times over 3 years. Between 2006 and 2010, there were 71,948 Medicare fee-for-service beneficiaries who received dual-chamber ICDs. Cumulative device-specific unadjusted 3-year event rates varied for three surveyed safety signals: death from any cause, 12.8%-20.9%; nonfatal ICD-related adverse events, 19.3%-26.3%; and death from any cause or nonfatal ICD-related adverse event, 27.1%-37.6%. Agreement among safety signals detected/not detected between the time-to-event and DELTA approaches was 90.9% (360 of 396, k =0.068), between the time-to-event and embedded feature-selection approaches was 91.7% (363 of 396, k =-0.028), and between the DELTA and embedded feature selection approaches was 88.1% (349 of 396, k =-0.042). Three statistical approaches, including one machine learning method, identified important safety signals, but without exact agreement. Ensemble methods may be needed to detect all safety signals for further evaluation during medical device surveillance.
Quality and Safety Education for Nurses (QSEN): The Key is Systems Thinking.
Dolansky, Mary A; Moore, Shirley M
2013-09-30
Over a decade has passed since the Institute of Medicine's reports on the need to improve the American healthcare system, and yet only slight improvement in quality and safety has been reported. The Quality and Safety Education for Nurses (QSEN) initiative was developed to integrate quality and safety competencies into nursing education. The current challenge is for nurses to move beyond the application of QSEN competencies to individual patients and families and incorporate systems thinking in quality and safety education and healthcare delivery. This article provides a history of QSEN and proposes a framework in which systems thinking is a critical aspect in the application of the QSEN competencies. We provide examples of how using this framework expands nursing focus from individual care to care of the system and propose ways to teach and measure systems thinking. The conclusion calls for movement from personal effort and individual care to a focus on care of the system that will accelerate improvement of healthcare quality and safety.
[Risk management in anesthesia and critical care medicine].
Eisold, C; Heller, A R
2017-03-01
Throughout its history, anesthesia and critical care medicine has experienced vast improvements to increase patient safety. Consequently, anesthesia has never been performed on such a high level as it is being performed today. As a result, we do not always fully perceive the risks involved in our daily activity. A survey performed in Swiss hospitals identified a total of 169 hot spots which endanger patient safety. It turned out that there is a complex variety of possible errors that can only be tackled through consistent implementation of a safety culture. The key elements to reduce complications are continuing staff education, algorithms and standard operating procedures (SOP), working according to the principles of crisis resource management (CRM) and last but not least the continuous work-up of mistakes identified by critical incident reporting systems.
Birko, Stanislav; Dove, Edward S.; Özdemir, Vural
2015-01-01
Access to clean water is a grand challenge in the 21st century. Water safety testing for pathogens currently depends on surrogate measures such as fecal indicator bacteria (e.g., E. coli). Metagenomics concerns high-throughput, culture-independent, unbiased shotgun sequencing of DNA from environmental samples that might transform water safety by detecting waterborne pathogens directly instead of their surrogates. Yet emerging innovations such as metagenomics are often fiercely contested. Innovations are subject to shaping/construction not only by technology but also social systems/values in which they are embedded, such as experts’ attitudes towards new scientific evidence. We conducted a classic three-round Delphi survey, comprised of 107 questions. A multidisciplinary expert panel (n = 24) representing the continuum of discovery scientists and policymakers evaluated the emergence of metagenomics tests. To the best of our knowledge, we report here the first Delphi foresight study of experts’ attitudes on (1) the top 10 priority evidentiary criteria for adoption of metagenomics tests for water safety, (2) the specific issues critical to governance of metagenomics innovation trajectory where there is consensus or dissensus among experts, (3) the anticipated time lapse from discovery to practice of metagenomics tests, and (4) the role and timing of public engagement in development of metagenomics tests. The ability of a test to distinguish between harmful and benign waterborne organisms, analytical/clinical sensitivity, and reproducibility were the top three evidentiary criteria for adoption of metagenomics. Experts agree that metagenomic testing will provide novel information but there is dissensus on whether metagenomics will replace the current water safety testing methods or impact the public health end points (e.g., reduction in boil water advisories). Interestingly, experts view the publics relevant in a “downstream capacity” for adoption of metagenomics rather than a co-productionist role at the “upstream” scientific design stage of metagenomics tests. In summary, these findings offer strategic foresight to govern metagenomics innovations symmetrically: by identifying areas where acceleration (e.g., consensus areas) and deceleration/reconsideration (e.g., dissensus areas) of the innovation trajectory might be warranted. Additionally, we show how scientific evidence is subject to potential social construction by experts’ value systems and the need for greater upstream public engagement on metagenomics innovations. PMID:26066837
A Validation Metrics Framework for Safety-Critical Software-Intensive Systems
2009-03-01
so does its definition, tools, and techniques, including means for measuring the validation activity, its outputs, and impact on development...independent of the SDLP. When considering the above SDLPs from the safety engineering team’s perspective, there are also large impacts on the way... impact . Interpretation of any actionable metric data will need to be undertaken in the context of the SDLP. 2. Safety Input The software safety
ASIL determination for motorbike's Electronics Throttle Control System (ETCS) mulfunction
NASA Astrophysics Data System (ADS)
Zaman Rokhani, Fakhrul; Rahman, Muhammad Taqiuddin Abdul; Ain Kamsani, Noor; Sidek, Roslina Mohd; Saripan, M. Iqbal; Samsudin, Khairulmizam; Khair Hassan, Mohd
2017-11-01
Electronics Throttle Control System (ETCS) is the principal electronic unit in all fuel injection engine motorbike, augmenting the engine performance efficiency in comparison to the conventional carburetor based engine. ETCS is regarded as a safety-critical component, whereby ETCS malfunction can cause unintended acceleration or deceleration event, which can be hazardous to riders. In this study, Hazard Analysis and Risk Assessment, an ISO26262 functional safety standard analysis has been applied on motorbike's ETCS to determine the required automotive safety integrity level. Based on the analysis, the established automotive safety integrity level can help to derive technical and functional safety measures for ETCS development.
A quantitative risk-based model for reasoning over critical system properties
NASA Technical Reports Server (NTRS)
Feather, M. S.
2002-01-01
This position paper suggests the use of a quantitative risk-based model to help support reeasoning and decision making that spans many of the critical properties such as security, safety, survivability, fault tolerance, and real-time.
Can a digital medicine system improve adherence to antipsychotic treatment?
Papola, D; Gastaldon, C; Ostuzzi, G
2018-06-01
A substantial proportion of people with mental health conditions do not adhere to prescribed pharmacological treatments. Poor adherence is probably one of the most critical elements contributing to relapse in people with schizophrenia and other severe mental disorders. In order to tackle this global issue, in November 2017 the Food and Drug Administration approved a tablet formulation of the atypical antipsychotic aripiprazole embedded with a novel digital adherence-assessment device. In this commentary, we critically appraised the potential beneficial and harmful consequences of this new digital formulation of aripiprazole, and we highlighted expected implications for clinical practice.
Energy efficiency of task allocation for embedded JPEG systems.
Fan, Yang-Hsin; Wu, Jan-Ou; Wang, San-Fu
2014-01-01
Embedded system works everywhere for repeatedly performing a few particular functionalities. Well-known products include consumer electronics, smart home applications, and telematics device, and so forth. Recently, developing methodology of embedded systems is applied to conduct the design of cloud embedded system resulting in the applications of embedded system being more diverse. However, the more energy consumes result from the more embedded system works. This study presents hyperrectangle technology (HT) to embedded system for obtaining energy saving. The HT adopts drift effect to construct embedded systems with more hardware circuits than software components or vice versa. It can fast construct embedded system with a set of hardware circuits and software components. Moreover, it has a great benefit to fast explore energy consumption for various embedded systems. The effects are presented by assessing a JPEG benchmarks. Experimental results demonstrate that the HT, respectively, achieves the energy saving by 29.84%, 2.07%, and 68.80% on average to GA, GHO, and Lin.
Energy Efficiency of Task Allocation for Embedded JPEG Systems
2014-01-01
Embedded system works everywhere for repeatedly performing a few particular functionalities. Well-known products include consumer electronics, smart home applications, and telematics device, and so forth. Recently, developing methodology of embedded systems is applied to conduct the design of cloud embedded system resulting in the applications of embedded system being more diverse. However, the more energy consumes result from the more embedded system works. This study presents hyperrectangle technology (HT) to embedded system for obtaining energy saving. The HT adopts drift effect to construct embedded systems with more hardware circuits than software components or vice versa. It can fast construct embedded system with a set of hardware circuits and software components. Moreover, it has a great benefit to fast explore energy consumption for various embedded systems. The effects are presented by assessing a JPEG benchmarks. Experimental results demonstrate that the HT, respectively, achieves the energy saving by 29.84%, 2.07%, and 68.80% on average to GA, GHO, and Lin. PMID:24982983
Embedded Web Technology: Applying World Wide Web Standards to Embedded Systems
NASA Technical Reports Server (NTRS)
Ponyik, Joseph G.; York, David W.
2002-01-01
Embedded Systems have traditionally been developed in a highly customized manner. The user interface hardware and software along with the interface to the embedded system are typically unique to the system for which they are built, resulting in extra cost to the system in terms of development time and maintenance effort. World Wide Web standards have been developed in the passed ten years with the goal of allowing servers and clients to intemperate seamlessly. The client and server systems can consist of differing hardware and software platforms but the World Wide Web standards allow them to interface without knowing about the details of system at the other end of the interface. Embedded Web Technology is the merging of Embedded Systems with the World Wide Web. Embedded Web Technology decreases the cost of developing and maintaining the user interface by allowing the user to interface to the embedded system through a web browser running on a standard personal computer. Embedded Web Technology can also be used to simplify an Embedded System's internal network.
Embedding health literacy into health systems: a case study of a regional health service.
Vellar, Lucia; Mastroianni, Fiorina; Lambert, Kelly
2017-12-01
Objective The aim of the present study was to describe how one regional health service the Illawarra Shoalhaven Local Health District embedded health literacy principles into health systems over a 3-year period. Methods Using a case study approach, this article describes the development of key programs and the manner in which clinical incidents were used to create a health environment that allows consumers the right to equitably access quality health services and to participate in their own health care. Results The key outcomes demonstrating successful embedding of health literacy into health systems in this regional health service include the creation of a governance structure and web-based platform for developing and testing plain English consumer health information, a clearly defined process to engage with consumers, development of the health literacy ambassador training program and integrating health literacy into clinical quality improvement processes via a formal program with consumers to guide processes such as improvements to access and navigation around hospital sites. Conclusions The Illawarra Shoalhaven Local Health District has developed an evidence-based health literacy framework, guided by the core principles of universal precaution and organisational responsibility. Health literacy was also viewed as both an outcome and a process. The approach taken by the Illawarra Shoalhaven Local Health District to address poor health literacy in a coordinated way has been recognised by the Australian Commission on Safety and Quality in Health Care as an exemplar of a coordinated approach to embed health literacy into health systems. What is known about the topic? Poor health literacy is a significant national concern in Australia. The leadership, governance and consumer partnership culture of a health organisation can have considerable effects on an individual's ability to access, understand and apply the health-related information and services available to them. Currently, only 40% of consumers in Australia have the health literacy skills needed to understand everyday health information to effectively access and use health services. What does this paper add? Addressing health literacy in a coordinated way has the potential to increase safety and quality of care. This paper outlines the practical and sustainable actions the Illawarra Shoalhaven Local Health District took to partner with consumers to address health literacy and to improve the health experience and health outcomes of consumers. Embedding health literacy into public health services requires a coordinated whole-of-organisation approach; it requires the integration of leadership and governance, revision of consumer health information and revision of consumer and staff processes to effect change and support the delivery of health-literate healthcare services. What are the implications for practitioners? Embedding health literacy into health systems promotes equitable, safe and quality healthcare. Practitioners in a health-literate environment adopt consumer-centred communication and care strategies, provide information in a way that is easy to understand and follow and involve consumers and their families in decisions regarding and management of the consumer's care.
Towards a mLearning training solution to the adoption of a CPOE system.
Pakonstantinou, Despoina; Poulymenopoulou, Mikaela; Malamateniou, Flora; Vassilacopoulos, George
2012-01-01
Computerized Physician Order Entry (CPOE) has been introduced as a solution that can fundamentally change the way healthcare is provided, affecting all types of healthcare stakeholders and improving healthcare decisions, patient outcomes, patient safety and efficiency. However, a relatively small proportion of healthcare organizations have implemented CPOE systems, due to its technological complexity and to its low acceptance rate by healthcare professionals who largely disregard the value of CPOE in efficient healthcare delivery. An online training facility embedded within a CPOE service may increase the likelihood of its adoption by healthcare professionals as it offers them guidelines on how to perform each task of the CPOE service. In contrast to CPOE, on the other hand, handheld devices and other mobile technologies have showed an increased adoption rate. This paper considers a CPOE service that can be accessed by authorized healthcare professionals through their mobile devices anytime anywhere, and allows embedded training content, which has been developed through a learning management system (LMS) to be presented to the user automatically upon request.
[Implementation of a safety and health planning system in a teaching hospital].
Mariani, F; Bravi, C; Dolcetti, L; Moretto, A; Palermo, A; Ronchin, M; Tonelli, F; Carrer, P
2007-01-01
University Hospital "L. Sacco" had started in 2006 a two-year project in order to set up a "Health and Safety Management System (HSMS)" referring to the technical guideline OHSAS 18001:1999 and the UNI and INAIL "Guidelines for a health and safety management system at workplace". So far, the following operations had been implemented: Setting up of a specific Commission within the Risk Management Committee; Identification and appointment of Departmental Representatives of HSMS; Carrying out of a training course addressed to Workers Representatives for Safety and Departmental Representatives of HSMS; Development of an Integrated Informative System for Prevention and Safety; Auditors qualification; Inspection of the Occupational Health Unit and the Prevention and Safety Service: reporting of critical situations and monitoring solutions adopted. Short term objectives are: Self-evaluation through check-lists of each department; Sharing of the Improvement Plan among the departments of the hospital; Planning of Health and Safety training activities in the framework of the Hospital Training Plan; Safety audit.
Interprofessional team management in pediatric critical care: some challenges and possible solutions
Stocker, Martin; Pilgrim, Sina B; Burmester, Margarita; Allen, Meredith L; Gijselaers, Wim H
2016-01-01
Background Aiming for and ensuring effective patient safety is a major priority in the management and culture of every health care organization. The pediatric intensive care unit (PICU) has become a workplace with a high diversity of multidisciplinary physicians and professionals. Therefore, delivery of high-quality care with optimal patient safety in a PICU is dependent on effective interprofessional team management. Nevertheless, ineffective interprofessional teamwork remains ubiquitous. Methods We based our review on the framework for interprofessional teamwork recently published in association with the UK Centre for Advancement of Interprofessional Education. Articles were selected to achieve better understanding and to include and translate new ideas and concepts. Findings The barrier between autonomous nurses and doctors in the PICU within their silos of specialization, the failure of shared mental models, a culture of disrespect, and the lack of empowering parents as team members preclude interprofessional team management and patient safety. A mindset of individual responsibility and accountability embedded in a network of equivalent partners, including the patient and their family members, is required to achieve optimal interprofessional care. Second, working competently as an interprofessional team is a learning process. Working declared as a learning process, psychological safety, and speaking up are pivotal factors to learning in daily practice. Finally, changes in small steps at the level of the microlevel unit are the bases to improve interprofessional team management and patient safety. Once small things with potential impact can be changed in one’s own unit, engagement of health care professionals occurs and projects become accepted. Conclusion Bottom–up patient safety initiatives encouraging participation of every single care provider by learning effective interprofessional team management within daily practice may be an effective way of fostering patient safety. PMID:26955279
Stocker, Martin; Pilgrim, Sina B; Burmester, Margarita; Allen, Meredith L; Gijselaers, Wim H
2016-01-01
Aiming for and ensuring effective patient safety is a major priority in the management and culture of every health care organization. The pediatric intensive care unit (PICU) has become a workplace with a high diversity of multidisciplinary physicians and professionals. Therefore, delivery of high-quality care with optimal patient safety in a PICU is dependent on effective interprofessional team management. Nevertheless, ineffective interprofessional teamwork remains ubiquitous. We based our review on the framework for interprofessional teamwork recently published in association with the UK Centre for Advancement of Interprofessional Education. Articles were selected to achieve better understanding and to include and translate new ideas and concepts. The barrier between autonomous nurses and doctors in the PICU within their silos of specialization, the failure of shared mental models, a culture of disrespect, and the lack of empowering parents as team members preclude interprofessional team management and patient safety. A mindset of individual responsibility and accountability embedded in a network of equivalent partners, including the patient and their family members, is required to achieve optimal interprofessional care. Second, working competently as an interprofessional team is a learning process. Working declared as a learning process, psychological safety, and speaking up are pivotal factors to learning in daily practice. Finally, changes in small steps at the level of the microlevel unit are the bases to improve interprofessional team management and patient safety. Once small things with potential impact can be changed in one's own unit, engagement of health care professionals occurs and projects become accepted. Bottom-up patient safety initiatives encouraging participation of every single care provider by learning effective interprofessional team management within daily practice may be an effective way of fostering patient safety.
The 12th International Conference on Computer Safety, Reliability and Security
1993-10-29
then used [10]. The adequacy of the proposed methodology is shown through the design and the validation of a simple control system: a train set example...satisfying the safety condition. 4 Conclusions In this paper we have presented a methodology which can be used for the design of safety-critical systems...has a Burner but no Detector (or the Detector is permanently non -active). The PA: G1 for this design is shown in Fig 3a. The probability matrices are
Evaluation of Design Assurance Regulations for Safety of Space Navigation Services
NASA Astrophysics Data System (ADS)
Ratti, B.; Sarno, M.; De Andreis, C.
2005-12-01
The European Space Agency (ESA), the European Community (EC), and the European Organisation for the Safety of Air Navigation (Eurocontrol) are contributing to the development of a Global positioning and Navigation Satellite System, known as GNSS. The development programme is carried out in two main steps:• GNSS-1: the first-generation system, based on signals received from the GPS (USA) and GLONASS (Russia) constellations, and augmentation systems like EGNOS (European Geostationary Navigation Overlay Service)• GNSS-2: the second-generation system, that will achieve the ultimate objective of European sovereignty for position determination, navigation and time dissemination. This system, named Galileo, comprises a global space and ground control infrastructure.The Galileo navigation signal will be used in the frame of safety-critical transport applications, thus it is necessary to assess the space safety assurance activity against the civil safety regulations and safety management system.. RTCA DO-254 and IEC 61508 standards, considered as part of best practice engineering references, for the development of safety- related systems in most applications, were selected during phases B2 and C0 of the Galileo project for this purpose.
EVA safety: Space suit system interoperability
NASA Technical Reports Server (NTRS)
Skoog, A. I.; McBarron, J. W.; Abramov, L. P.; Zvezda, A. O.
1995-01-01
The results and the recommendations of the International Academy of Astronautics extravehicular activities (IAA EVA) Committee work are presented. The IAA EVA protocols and operation were analyzed for harmonization procedures and for the standardization of safety critical and operationally important interfaces. The key role of EVA and how to improve the situation based on the identified EVA space suit system interoperability deficiencies were considered.
Superradiant phase transition with graphene embedded in one dimensional optical cavity
NASA Astrophysics Data System (ADS)
Li, Benliang; Liu, Tao; Hewak, Daniel W.; Wang, Qi Jie
2018-01-01
We theoretically investigate the cavity QED of graphene embedded in an optical cavity under perpendicular magnetic field. We consider the coupling of cyclotron transition and a multimode cavity described by a multimode Dicke model. This model exhibits a superradiant quantum phase transition, which we describe exactly in an effective Hamiltonian approach. The complete excitation spectrum in both the normal phase and superradiant phase regimes is given. In contrast to the single mode case, multimode coupling of cavity photon and cyclotron transition can greatly reduce the critical vacuum Rabi frequency required for quantum phase transition, and dramatically enhance the superradiant emission by fast modulating the Hamiltonian. Our work paves a way to experimental explorations of quantum phase transitions in solid state systems.
Mitigating Motion Base Safety Issues: The NASA LaRC CMF Implementation
NASA Technical Reports Server (NTRS)
Bryant, Richard B., Jr.; Grupton, Lawrence E.; Martinez, Debbie; Carrelli, David J.
2005-01-01
The NASA Langley Research Center (LaRC), Cockpit Motion Facility (CMF) motion base design has taken advantage of inherent hydraulic characteristics to implement safety features using hardware solutions only. Motion system safety has always been a concern and its implementation is addressed differently by each organization. Some approaches rely heavily on software safety features. Software which performs safety functions is subject to more scrutiny making its approval, modification, and development time consuming and expensive. The NASA LaRC's CMF motion system is used for research and, as such, requires that the software be updated or modified frequently. The CMF's customers need the ability to update the simulation software frequently without the associated cost incurred with safety critical software. This paper describes the CMF engineering team's approach to achieving motion base safety by designing and implementing all safety features in hardware, resulting in applications software (including motion cueing and actuator dynamic control) being completely independent of the safety devices. This allows the CMF safety systems to remain intact and unaffected by frequent research system modifications.
Building food safety into the company culture: a look at Maple Leaf Foods.
Lone, Jespersen; Huffman, Randy
2014-07-01
Maple Leaf Foods learned a hard lesson following its tragic 2008 Listeria outbreak that ended up taking the lives of 23 Canadians. The organization has since 2008 transformed its commitment to food safety with a strong drive and manifest in embedding sustainable food safety behaviours into the existing company culture. Its focus on combining technical risk analysis with behavioural sciences has led to the development and deployment of a food safety strategy deeply rooted in the company values and management commitment. Using five tactics described in this article the organization has been on a journey towards food safety transformation through adoption of best practices for people and systems. The approach to food safety has been one where food safety is treated as a non-competitive issue and Maple Leaf Foods have been open to sharing learning about what happened and how the organization will continue to take a leadership position in food safety to continuously raise the bar for food safety across the industry. Maple Leaf Foods has benefited tremendously by learning about best practice from numerous companies in North America and around the world. The authors believe this brief story will bring value to others as we continue to learn and improve.
Virtual Egalitarianism, Critical Pedagogy, and Geographic Education
ERIC Educational Resources Information Center
Lukinbeal, Chris; Allen, Casey D.
2007-01-01
This article explores the implementation of critical pedagogic practices into a graduate level landscape seminar Web site. Critical pedagogy seeks to reconfigure student-teacher relationships and disrupt embedded power regimes within academia and society. Critical pedagogic practices create a dialogue amongst learners, where everyone has a stake…
Requirements-Based Conformance Testing of ARINC 653 Real-Time Operating Systems
NASA Astrophysics Data System (ADS)
Maksimov, Andrey
2010-08-01
Requirements-based testing is emphasized in avionics certification documents because this strategy has been found to be the most effective at revealing errors. This paper describes the unified requirements-based approach to the creation of conformance test suites for mission-critical systems. The approach uses formal machine-readable specifications of requirements and finite state machine model for test sequences generation on-the-fly. The paper also presents the test system for automated test generation for ARINC 653 services built on this approach. Possible application of the presented approach to various areas of avionics embedded systems testing is discussed.
Mumtaz, Zubia; Bowen, Sarah; Mumtaz, Rubina
2012-01-01
Contemporary public policy, supported by international arbitrators of blood policy such as the World Health Organization and the International Federation of the Red Cross, asserts that the safest blood is that donated by voluntary, non-remunerated donors from low-risk groups of the population. These policies promote anonymous donation and discourage kin-based or replacement donation. However, there is reason to question whether these policies, based largely on Western research and beliefs, are the most appropriate for ensuring an adequate safe blood supply in many other parts of the world. This research explored the various and complex meanings embedded in blood using empirical ethnographic data from Pakistan, with the intent of informing development of a national blood policy in that country. Using a focused ethnographic approach, data were collected in 26 in-depth interviews, 6 focus group discussions, 12 key informant interviews and 25 hours of observations in blood banks and maternity and surgical wards. The key finding was that notions of caste-based purity of blood, together with the belief that donors and recipients are symbolically knitted in a kin relationship, place a preference on kin-blood. The anonymity inherent in current systems of blood extraction, storage and use as embedded in contemporary policy discourse and practice was problematic as it blurred distinctions that were important within this society. The article highlights the importance—to ensuring a safe blood supply—of basing blood procurement policies on local, context-specific belief systems rather than relying on uniform, one-size-fits-all global policies. Drawing on our empirical findings and the literature, it is argued that the practice of kin-donated blood remains a feasible alternative to the global ideal of voluntary, anonymous donations. There is a need to focus on developing context-sensitive strategies for promoting blood safety, and critically revisit the assumptions underlying contemporary global blood procurement policies. PMID:21372061
System Analysis and Performance Benefits of an Optimized Rotorcraft Propulsion System
NASA Technical Reports Server (NTRS)
Bruckner, Robert J.
2007-01-01
The propulsion system of rotorcraft vehicles is the most critical system to the vehicle in terms of safety and performance. The propulsion system must provide both vertical lift and forward flight propulsion during the entire mission. Whereas propulsion is a critical element for all flight vehicles, it is particularly critical for rotorcraft due to their limited safe, un-powered landing capability. This unparalleled reliability requirement has led rotorcraft power plants down a certain evolutionary path in which the system looks and performs quite similarly to those of the 1960 s. By and large the advancements in rotorcraft propulsion have come in terms of safety and reliability and not in terms of performance. The concept of the optimized propulsion system is a means by which both reliability and performance can be improved for rotorcraft vehicles. The optimized rotorcraft propulsion system which couples an oil-free turboshaft engine to a highly loaded gearbox that provides axial load support for the power turbine can be designed with current laboratory proven technology. Such a system can provide up to 60% weight reduction of the propulsion system of rotorcraft vehicles. Several technical challenges are apparent at the conceptual design level and should be addressed with current research.
Brief history of patient safety culture and science.
Ilan, Roy; Fowler, Robert
2005-03-01
The science of safety is well established in such disciplines as the automotive and aviation industry. In this brief history of safety science as it pertains to patient care, we review remote and recent publications that have guided the maturation of this field that has particular relevance to the complex structure of systems, personnel, and therapies involved in caring for the critically ill.
Salmon, Paul M; Read, Gemma J M; Stevens, Nicholas J
2016-11-01
Despite significant progress, road trauma continues to represent a global safety issue. In Queensland (Qld), Australia, there is currently a focus on preventing the 'fatal five' behaviours underpinning road trauma (drug and drink driving, distraction, seat belt wearing, speeding, and fatigue), along with an emphasis on a shared responsibility for road safety that spans road users, vehicle manufacturers, designers, policy makers etc. The aim of this article is to clarify who shares the responsibility for road safety in Qld and to determine what control measures are enacted to prevent the fatal five behaviours. This is achieved through the presentation of a control structure model that depicts the actors and organisations within the Qld road transport system along with the control and feedback relationships that exist between them. Validated through a Delphi study, the model shows a diverse set of actors and organisations who share the responsibility for road safety that goes beyond those discussed in road safety policies and strategies. The analysis also shows that, compared to other safety critical domains, there are less formal control structures in road transport and that opportunities exist to add new controls and strengthen existing ones. Relationships that influence rather than control are also prominent. Finally, when compared to other safety critical domains, the strength of road safety controls is brought into question. Copyright © 2016 Elsevier Ltd. All rights reserved.
Yin, Zhong; Zhang, Jianhua
2014-07-01
Identifying the abnormal changes of mental workload (MWL) over time is quite crucial for preventing the accidents due to cognitive overload and inattention of human operators in safety-critical human-machine systems. It is known that various neuroimaging technologies can be used to identify the MWL variations. In order to classify MWL into a few discrete levels using representative MWL indicators and small-sized training samples, a novel EEG-based approach by combining locally linear embedding (LLE), support vector clustering (SVC) and support vector data description (SVDD) techniques is proposed and evaluated by using the experimentally measured data. The MWL indicators from different cortical regions are first elicited by using the LLE technique. Then, the SVC approach is used to find the clusters of these MWL indicators and thereby to detect MWL variations. It is shown that the clusters can be interpreted as the binary class MWL. Furthermore, a trained binary SVDD classifier is shown to be capable of detecting slight variations of those indicators. By combining the two schemes, a SVC-SVDD framework is proposed, where the clear-cut (smaller) cluster is detected by SVC first and then a subsequent SVDD model is utilized to divide the overlapped (larger) cluster into two classes. Finally, three-class MWL levels (low, normal and high) can be identified automatically. The experimental data analysis results are compared with those of several existing methods. It has been demonstrated that the proposed framework can lead to acceptable computational accuracy and has the advantages of both unsupervised and supervised training strategies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Brooks, Benjamin
2008-01-01
Small to Medium Sized Enterprises (SMEs) form the majority of Australian businesses. This study uses ethnographic research methods to describe the organizational culture of a small furniture-manufacturing business in southern Australia. Results show a range of cultural assumptions variously 'embedded' within the enterprise. In line with memetics - Richard Dawkin's cultural application of Charles Darwin's theory of Evolution by Natural Selection, the author suggests that these assumptions compete to be replicated and retained within the organization. The author suggests that dominant assumptions are naturally selected, and that the selection can be better understood by considering the cultural assumptions in reference to Darwin's original principles and Frederik Barth's anthropological framework of knowledge. The results are discussed with reference to safety systems, negative cultural elements called Cultural Safety Viruses, and how our understanding of this particular organizational culture might be used to build resistance to these viruses.
Nuclear criticality safety staff training and qualifications at Los Alamos National Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Monahan, S.P.; McLaughlin, T.P.
1997-05-01
Operations involving significant quantities of fissile material have been conducted at Los Alamos National Laboratory continuously since 1943. Until the advent of the Laboratory`s Nuclear Criticality Safety Committee (NCSC) in 1957, line management had sole responsibility for controlling criticality risks. From 1957 until 1961, the NCSC was the Laboratory body which promulgated policy guidance as well as some technical guidance for specific operations. In 1961 the Laboratory created the position of Nuclear Criticality Safety Office (in addition to the NCSC). In 1980, Laboratory management moved the Criticality Safety Officer (and one other LACEF staff member who, by that time, wasmore » also working nearly full-time on criticality safety issues) into the Health Division office. Later that same year the Criticality Safety Group, H-6 (at that time) was created within H-Division, and staffed by these two individuals. The training and education of these individuals in the art of criticality safety was almost entirely self-regulated, depending heavily on technical interactions between each other, as well as NCSC, LACEF, operations, other facility, and broader criticality safety community personnel. Although the Los Alamos criticality safety group has grown both in size and formality of operations since 1980, the basic philosophy that a criticality specialist must be developed through mentoring and self motivation remains the same. Formally, this philosophy has been captured in an internal policy, document ``Conduct of Business in the Nuclear Criticality Safety Group.`` There are no short cuts or substitutes in the development of a criticality safety specialist. A person must have a self-motivated personality, excellent communications skills, a thorough understanding of the principals of neutron physics, a safety-conscious and helpful attitude, a good perspective of real risk, as well as a detailed understanding of process operations and credible upsets.« less
RESLanjut: The learning media for improve students understanding in embedded systems
NASA Astrophysics Data System (ADS)
Indrianto, Susanti, Meilia Nur Indah; Karina, Djunaidi
2017-08-01
The use of network in embedded system can be done with many kinds of network, with the use of mobile phones, bluetooths, modems, ethernet cards, wireless technology and so on. Using network in embedded system could help people to do remote controlling. On previous research, researchers found that many students have the ability to comprehend the basic concept of embedded system. They could also make embedded system tools but without network integration. And for that, a development is needed for the embedded system module. The embedded system practicum module design needs a prototype method in order to achieve the desired goal. The prototype method is often used in the real world. Or even, a prototype method is a part of products that consist of logic expression or external physical interface. The embedded system practicum module is meant to increase student comprehension of embedded system course, and also to encourage students to innovate on technology based tools. It is also meant to help teachers to teach the embedded system concept on the course. The student comprehension is hoped to increase with the use of practicum course.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-19
...; or (iii) An uncommanded engine shutdown that jeopardizes safety. Design control activity. (i) With... aviation critical safety item is to be used; and (ii) With respect to a ship critical safety item, means...-AG92 Defense Federal Acquisition Regulation Supplement; Identification of Critical Safety Items (DFARS...
Wireless communication and spectrum sharing for public safety in the United States.
Kapucu, Naim; Haupt, Brittany; Yuksel, Murat
2016-01-01
With the vast number of fragmented, independent public safety wireless communication systems, the United States is encountering major challenges with enhancing interoperability and effectively managing costs while sharing limited availability of critical spectrum. The traditional hierarchical approach of emergency management does not always allow for needed flexibility and is not a mandate. A national system would reduce equipment needs, increase effectiveness, and enrich quality and coordination of response; however, it is dependent on integrating the commercial market. This article discusses components of an ideal national wireless public safety system consists along with key policies in regulating wireless communication and spectrum sharing for public safety and challenges for implementation.
NASA Technical Reports Server (NTRS)
Gupta, Pramod; Schumann, Johann
2004-01-01
High reliability of mission- and safety-critical software systems has been identified by NASA as a high-priority technology challenge. We present an approach for the performance analysis of a neural network (NN) in an advanced adaptive control system. This problem is important in the context of safety-critical applications that require certification, such as flight software in aircraft. We have developed a tool to measure the performance of the NN during operation by calculating a confidence interval (error bar) around the NN's output. Our tool can be used during pre-deployment verification as well as monitoring the network performance during operation. The tool has been implemented in Simulink and simulation results on a F-15 aircraft are presented.
Unfree markets: socially embedded informal health providers in northern Karnataka, India.
George, Asha; Iyer, Aditi
2013-11-01
The dynamics of informal health markets in marginalised regions are relevant to policy discourse in India, but are poorly understood. We examine how informal health markets operate from the viewpoint of informal providers (those without any government-recognised medical degrees, otherwise known as RMPs) by drawing upon data from a household survey in 2002, a provider census in 2004 and ongoing field observations from a research site in Koppal district, Karnataka, India. We find that despite their illegality, RMPs depend on government and private providers for their training and referral networks. Buffeted by unregulated market pressures, RMPs are driven to provide allopathic commodities regardless of need, but can also be circumspect in their practice. Though motivated by profit, their socially embedded practice at community level at times undermines their ability to ensure payment of fees for their services. In addition, RMPs feel that communities can threaten them via violence or malicious rumours, leading them to seek political favour and social protection from village elites and elected representatives. RMPs operate within negotiated quid pro quo bargains that lead to tenuous reciprocity or fragile trust between them and the communities in which they practise. In the context of this 'unfree' market, some RMPs reported being more embedded in health systems, more responsive to communities and more vulnerable to unregulated market pressures than others. Understanding the heterogeneity, nuanced motivations and the embedded social relations that mark informal providers in the health systems, markets and communities they work in, is critical for health system reforms. Copyright © 2013 Elsevier Ltd. All rights reserved.
ESAS Deliverable PS 1.1.2.3: Customer Survey on Code Generations in Safety-Critical Applications
NASA Technical Reports Server (NTRS)
Schumann, Johann; Denney, Ewen
2006-01-01
Automated code generators (ACG) are tools that convert a (higher-level) model of a software (sub-)system into executable code without the necessity for a developer to actually implement the code. Although both commercially supported and in-house tools have been used in many industrial applications, little data exists on how these tools are used in safety-critical domains (e.g., spacecraft, aircraft, automotive, nuclear). The aims of the survey, therefore, were threefold: 1) to determine if code generation is primarily used as a tool for prototyping, including design exploration and simulation, or for fiight/production code; 2) to determine the verification issues with code generators relating, in particular, to qualification and certification in safety-critical domains; and 3) to determine perceived gaps in functionality of existing tools.
Apollo Spacecraft and Saturn V Launch Vehicle Pyrotechnics/Explosive Devices
NASA Technical Reports Server (NTRS)
Interbartolo, Michael
2009-01-01
The Apollo Mission employs more than 210 pyrotechnic devices per mission.These devices are either automatic of commanded from the Apollo spacecraft systems. All devices require high reliability and safety and most are classified as either crew safety critical or mission critical. Pyrotechnic devices have a wide variety of applications including: launch escape tower separation, separation rocket ignition, parachute deployment and release and electrical circuit opening and closing. This viewgraph presentation identifies critical performance, design requirements and safety measures used to ensure quality, reliability and performance of Apollo pyrotechnic/explosive devices. The major components and functions of a typical Apollo pyrotechnic/explosive device are listed and described (initiators, cartridge assemblies, detonators, core charges). The presentation also identifies the major locations and uses for the devices on: the Command and Service Module, Lunar Module and all stages of the launch vehicle.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skiles, S. K.
1994-12-22
An inductive double-contingency analysis (DCA) method developed by the criticality safety function at the Savannah River Site, was applied in Criticality Safety Evaluations (CSEs) of five major plant process systems at the Westinghouse Electric Corporation`s Commercial Nuclear Fuel Manufacturing Plant in Columbia, South Carolina (WEC-Cola.). The method emphasizes a thorough evaluation of the controls intended to provide barriers against criticality for postulated initiating events, and has been demonstrated effective at identifying common mode failure potential and interdependence among multiple controls. A description of the method and an example of its application is provided.
Critical Thinking: Frameworks and Models for Teaching
ERIC Educational Resources Information Center
Fahim, Mansoor; Eslamdoost, Samaneh
2014-01-01
Developing critical thinking since the educational revolution gave rise to flourishing movements toward embedding critical thinking (CT henceforth) stimulating classroom activities in educational settings. Nevertheless the process faced with complications such as teachability potentiality, lack of practical frameworks concerning actualization of…
Integrated Design and Implementation of Embedded Control Systems with Scilab
Ma, Longhua; Xia, Feng; Peng, Zhe
2008-01-01
Embedded systems are playing an increasingly important role in control engineering. Despite their popularity, embedded systems are generally subject to resource constraints and it is therefore difficult to build complex control systems on embedded platforms. Traditionally, the design and implementation of control systems are often separated, which causes the development of embedded control systems to be highly time-consuming and costly. To address these problems, this paper presents a low-cost, reusable, reconfigurable platform that enables integrated design and implementation of embedded control systems. To minimize the cost, free and open source software packages such as Linux and Scilab are used. Scilab is ported to the embedded ARM-Linux system. The drivers for interfacing Scilab with several communication protocols including serial, Ethernet, and Modbus are developed. Experiments are conducted to test the developed embedded platform. The use of Scilab enables implementation of complex control algorithms on embedded platforms. With the developed platform, it is possible to perform all phases of the development cycle of embedded control systems in a unified environment, thus facilitating the reduction of development time and cost. PMID:27873827
Integrated Design and Implementation of Embedded Control Systems with Scilab.
Ma, Longhua; Xia, Feng; Peng, Zhe
2008-09-05
Embedded systems are playing an increasingly important role in control engineering. Despite their popularity, embedded systems are generally subject to resource constraints and it is therefore difficult to build complex control systems on embedded platforms. Traditionally, the design and implementation of control systems are often separated, which causes the development of embedded control systems to be highly timeconsuming and costly. To address these problems, this paper presents a low-cost, reusable, reconfigurable platform that enables integrated design and implementation of embedded control systems. To minimize the cost, free and open source software packages such as Linux and Scilab are used. Scilab is ported to the embedded ARM-Linux system. The drivers for interfacing Scilab with several communication protocols including serial, Ethernet, and Modbus are developed. Experiments are conducted to test the developed embedded platform. The use of Scilab enables implementation of complex control algorithms on embedded platforms. With the developed platform, it is possible to perform all phases of the development cycle of embedded control systems in a unified environment, thus facilitating the reduction of development time and cost.
Percolation of spatially constraint networks
NASA Astrophysics Data System (ADS)
Li, Daqing; Li, Guanliang; Kosmidis, Kosmas; Stanley, H. E.; Bunde, Armin; Havlin, Shlomo
2011-03-01
We study how spatial constraints are reflected in the percolation properties of networks embedded in one-dimensional chains and two-dimensional lattices. We assume long-range connections between sites on the lattice where two sites at distance r are chosen to be linked with probability p(r)~r-δ. Similar distributions have been found in spatially embedded real networks such as social and airline networks. We find that for networks embedded in two dimensions, with 2<δ<4, the percolation properties show new intermediate behavior different from mean field, with critical exponents that depend on δ. For δ<2, the percolation transition belongs to the universality class of percolation in Erdös-Rényi networks (mean field), while for δ>4 it belongs to the universality class of percolation in regular lattices. For networks embedded in one dimension, we find that, for δ<1, the percolation transition is mean field. For 1<δ<2, the critical exponents depend on δ, while for δ>2 there is no percolation transition as in regular linear chains.
Quantifying Pilot Contribution to Flight Safety During an In-Flight Airspeed Failure
NASA Technical Reports Server (NTRS)
Etherington, Timothy J.; Kramer, Lynda J.; Bailey, Randall E.; Kennedey, Kellie D.
2017-01-01
Accident statistics cite the flight crew as a causal factor in over 60% of large transport fatal accidents. Yet a well-trained and well-qualified crew is acknowledged as the critical center point of aircraft systems safety and an integral component of the entire commercial aviation system. A human-in-the-loop test was conducted using a Level D certified Boeing 737-800 simulator to evaluate the pilot's contribution to safety-of-flight during routine air carrier flight operations and in response to system failures. To quantify the human's contribution, crew complement was used as an independent variable in a between-subjects design. This paper details the crew's actions and responses while dealing with an in-flight airspeed failure. Accident statistics often cite flight crew error (Baker, 2001) as the primary contributor in accidents and incidents in transport category aircraft. However, the Air Line Pilots Association (2011) suggests "a well-trained and well-qualified pilot is acknowledged as the critical center point of the aircraft systems safety and an integral safety component of the entire commercial aviation system." This is generally acknowledged but cannot be verified because little or no quantitative data exists on how or how many accidents/incidents are averted by crew actions. Anecdotal evidence suggest crews handle failures on a daily basis and Aviation Safety Action Program data generally supports this assertion, even if the data is not released to the public. However without hard evidence, the contribution and means by which pilots achieve safety of flight is difficult to define. Thus, ways to improve the human ability to contribute or overcome deficiencies are ill-defined.
Procedure for Failure Mode, Effects, and Criticality Analysis (FMECA)
NASA Technical Reports Server (NTRS)
1966-01-01
This document provides guidelines for the accomplishment of Failure Mode, Effects, and Criticality Analysis (FMECA) on the Apollo program. It is a procedure for analysis of hardware items to determine those items contributing most to system unreliability and crew safety problems.
Use of a High-Flow Oxygen Delivery System in a Critically Ill Patient with Dementia
2008-12-01
February 1, 2007. http://www.fda.gov/ cdrh /safety/ 020107_vapotherm.html. Accessed October 7, 2008. HIGH-FLOW OXYGEN IN A CRITICALLY ILL PATIENT WITH DEMENTIA RESPIRATORY CARE • DECEMBER 2008 VOL 53 NO 12 1743
An autonomous structural health monitoring system for Waiau interchange.
DOT National Transportation Integrated Search
2013-03-01
Bridge infrastructure is a critical element of the transportation system which makes maintaining its safety and : performance vital to a healthy society. However, the civil infrastructure systems in the United States are decaying : at an accelerated ...
Improving the Wyoming Road Weather Information System
DOT National Transportation Integrated Search
1998-11-01
A two-year study of the Wyoming Road Weather Information System (RWIS) indicated that the system will facilitate and improve maintenance operations and enhance the safety and convenience of highway travel if certain critical improvements are made. Wi...
Human Factors in Aerospace: Examples from Projects at NASA Ames
NASA Technical Reports Server (NTRS)
Edwards, Tamsyn
2017-01-01
Human factors is a critical consideration in system performance and system safety. This presentation provides examples of how human factors can be utilized in a variety of applied research projects to create system wide benefits
NASA Technical Reports Server (NTRS)
Harris, C. E.; Jelalian, A. V.
1979-01-01
Analyses of the mounting and mount support systems of the clear air turbulence transmitters verify that satisfactory shock and vibration isolation are attained. The mount support structure conforms to flight crash safety requirements with high margins of safety. Restraint cables reinforce the mounts in the critical loaded forward direction limiting maximum forward system deflection to 1 1/4 inches.
9 CFR 417.4 - Validation, Verification, Reassessment.
Code of Federal Regulations, 2012 CFR
2012-01-01
... not have a HACCP plan because a hazard analysis has revealed no food safety hazards that are.... 417.4 Section 417.4 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... ACT HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.4 Validation, Verification...
9 CFR 417.4 - Validation, Verification, Reassessment.
Code of Federal Regulations, 2010 CFR
2010-01-01
... not have a HACCP plan because a hazard analysis has revealed no food safety hazards that are.... 417.4 Section 417.4 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... ACT HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.4 Validation, Verification...
9 CFR 417.4 - Validation, Verification, Reassessment.
Code of Federal Regulations, 2011 CFR
2011-01-01
... not have a HACCP plan because a hazard analysis has revealed no food safety hazards that are.... 417.4 Section 417.4 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... ACT HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.4 Validation, Verification...
Cyber Safety and Security for Reduced Crew Operations (RCO)
NASA Technical Reports Server (NTRS)
Driscoll, Kevin
2017-01-01
NASA and the Aviation Industry is looking into reduced crew operations (RCO) that would cut today's required two-person flight crews down to a single pilot with support from ground-based crews. Shared responsibility across air and ground personnel will require highly reliable and secure data communication and supporting automation, which will be safety-critical for passenger and cargo aircraft. This paper looks at the different types and degrees of authority delegation given from the air to the ground and the ramifications of each, including the safety and security hazards introduced, the mitigation mechanisms for these hazards, and other demands on an RCO system architecture which would be highly invasive into (almost) all safety-critical avionics. The adjacent fields of unmanned aerial systems and autonomous ground vehicles are viewed to find problems that RCO may face and related aviation accident scenarios are described. The paper explores possible data communication architectures to meet stringent performance and information security (INFOSEC) requirements of RCO. Subsequently, potential challenges for RCO data communication authentication, encryption and non-repudiation are identified. The approach includes a comprehensive safety-hazard analysis of the RCO system to determine top level INFOSEC requirements for RCO and proposes an option for effective RCO implementation. This paper concludes with questioning the economic viability of RCO in light of the expense of overcoming the operational safety and security hazards it would introduce.
ERIC Educational Resources Information Center
Pedrosa-de-Jesus, Helena; Moreira, Aurora; Lopes, Betina; Watts, Mike
2014-01-01
Background: Critical thinking is one of the very highest orders of cognitive abilities and a key competency in higher education. Asking questions is an important component of rich learning experiences, structurally embedded in the operations of critical thinking. Our clear sense is that critical thinking and, within that, critical questioning, is…
Certification Strategies using Run-Time Safety Assurance for Part 23 Autopilot Systems
NASA Technical Reports Server (NTRS)
Hook, Loyd R.; Clark, Matthew; Sizoo, David; Skoog, Mark A.; Brady, James
2016-01-01
Part 23 aircraft operation, and in particular general aviation, is relatively unsafe when compared to other common forms of vehicle travel. Currently, there exists technologies that could increase safety statistics for these aircraft; however, the high burden and cost of performing the requisite safety critical certification processes for these systems limits their proliferation. For this reason, many entities, including the Federal Aviation Administration, NASA, and the US Air Force, are considering new options for certification for technologies that will improve aircraft safety. Of particular interest, are low cost autopilot systems for general aviation aircraft, as these systems have the potential to positively and significantly affect safety statistics. This paper proposes new systems and techniques, leveraging run-time verification, for the assurance of general aviation autopilot systems, which would be used to supplement the current certification process and provide a viable path for near-term low-cost implementation. In addition, discussions on preliminary experimentation and building the assurance case for a system, based on these principles, is provided.
Agile Methods for Open Source Safety-Critical Software
Enquobahrie, Andinet; Ibanez, Luis; Cheng, Patrick; Yaniv, Ziv; Cleary, Kevin; Kokoori, Shylaja; Muffih, Benjamin; Heidenreich, John
2011-01-01
The introduction of software technology in a life-dependent environment requires the development team to execute a process that ensures a high level of software reliability and correctness. Despite their popularity, agile methods are generally assumed to be inappropriate as a process family in these environments due to their lack of emphasis on documentation, traceability, and other formal techniques. Agile methods, notably Scrum, favor empirical process control, or small constant adjustments in a tight feedback loop. This paper challenges the assumption that agile methods are inappropriate for safety-critical software development. Agile methods are flexible enough to encourage the right amount of ceremony; therefore if safety-critical systems require greater emphasis on activities like formal specification and requirements management, then an agile process will include these as necessary activities. Furthermore, agile methods focus more on continuous process management and code-level quality than classic software engineering process models. We present our experiences on the image-guided surgical toolkit (IGSTK) project as a backdrop. IGSTK is an open source software project employing agile practices since 2004. We started with the assumption that a lighter process is better, focused on evolving code, and only adding process elements as the need arose. IGSTK has been adopted by teaching hospitals and research labs, and used for clinical trials. Agile methods have matured since the academic community suggested they are not suitable for safety-critical systems almost a decade ago, we present our experiences as a case study for renewing the discussion. PMID:21799545
Agile Methods for Open Source Safety-Critical Software.
Gary, Kevin; Enquobahrie, Andinet; Ibanez, Luis; Cheng, Patrick; Yaniv, Ziv; Cleary, Kevin; Kokoori, Shylaja; Muffih, Benjamin; Heidenreich, John
2011-08-01
The introduction of software technology in a life-dependent environment requires the development team to execute a process that ensures a high level of software reliability and correctness. Despite their popularity, agile methods are generally assumed to be inappropriate as a process family in these environments due to their lack of emphasis on documentation, traceability, and other formal techniques. Agile methods, notably Scrum, favor empirical process control, or small constant adjustments in a tight feedback loop. This paper challenges the assumption that agile methods are inappropriate for safety-critical software development. Agile methods are flexible enough to encourage the rightamount of ceremony; therefore if safety-critical systems require greater emphasis on activities like formal specification and requirements management, then an agile process will include these as necessary activities. Furthermore, agile methods focus more on continuous process management and code-level quality than classic software engineering process models. We present our experiences on the image-guided surgical toolkit (IGSTK) project as a backdrop. IGSTK is an open source software project employing agile practices since 2004. We started with the assumption that a lighter process is better, focused on evolving code, and only adding process elements as the need arose. IGSTK has been adopted by teaching hospitals and research labs, and used for clinical trials. Agile methods have matured since the academic community suggested they are not suitable for safety-critical systems almost a decade ago, we present our experiences as a case study for renewing the discussion.
Mendel, Peter; Weinberg, Daniel A; Gall, Elizabeth M; Leuschner, Kristin J; Kahn, Katherine L
2014-02-01
Strengthening capacity across the healthcare system for improvement is critical to ensuring that past efforts and investments establish a foundation for sustaining progress in patient safety. The objective of this analysis was to identify key system capacity issues for sustainability from evaluation of the Action Plan to prevent healthcare-associated infections, a major national initiative launched by the US Department of Health and Human Services in 2009. The analysis involves the review and synthesis of results across the components of a 3-year evaluation of the Action Plan, as described in the evaluation framework and detailed in separate analyses elsewhere in this special issue. Data collection methods included interviews with government and private stakeholders, document and literature reviews, and observations of meetings and conferences at multiple time points. Key developments in healthcare-associated infection prevention system capacity were extracted on the basis of "major activities" identified through multiple methods and organized into the level of progress based on perspectives of multiple stakeholders. Activities within each level were then examined and compared according to our evaluation's framework of 4 system functions and 5 system properties. Key system capacity and sustainability issues for the Action Plan to be addressed centered on coordination and alignment (among participating agencies, with other federal initiatives, and across levels of healthcare), infrastructure for data and accountability (including more efficient technologies and unintended consequences), cultural embedding of prevention practices, and uncertainty and variability in resources. Sustainability depends on improvements across system functions and properties and how they reinforce each other. Change is more robust if different system elements support and incentivize behavior in similar directions.
Knowledge of Curriculum Embedded Mathematics: Exploring a Critical Domain of Teaching
ERIC Educational Resources Information Center
Remillard, Janine; Kim, Ok-Kyeong
2017-01-01
This paper proposes a framework for identifying the mathematical knowledge teachers activate when using curriculum resources. We use the term "knowledge of curriculum embedded mathematics" (KCEM) to refer to the mathematics knowledge activated by teachers when reading and interpreting mathematical tasks, instructional designs, and…
In situ monitoring of the integrity of bonded repair patches on aircraft and civil infrastructures
NASA Astrophysics Data System (ADS)
Kumar, Amrita; Roach, Dennis; Beard, Shawn; Qing, Xinlin; Hannum, Robert
2006-03-01
Monitoring the continued health of aircraft subsystems and identifying problems before they affect airworthiness has been a long-term goal of the aviation industry. Because in-service conditions and failure modes experienced by structures are generally complex and unknown, conservative calendar-based or usage-based scheduled maintenance practices are overly time-consuming, labor-intensive and expensive. Metal structures such as helicopters and other transportation systems are likely to develop fatigue cracks under cyclic loads and corrosive service environments. Early detection of cracks is a key element to prevent catastrophic failure and prolong structural life. Furthermore, as structures age, maintenance service frequency and costs increase while performance and availability decrease. Current non-destructive inspection (NDI) techniques that can potentially be used for this purpose typically involve complex, time-intensive procedures, which are labor-intensive and expensive. Most techniques require access to the damaged area on at least one side, and sometimes on both sides. This can be very difficult for monitoring of certain inaccessible regions. In those cases, inspection may require removal of access panels or even structural disassembly. Once access has been obtained, automated inspection techniques likely will not be practical due to the bulk of the required equipment. Results obtained from these techniques may also be sensitive to the sweep speed, tool orientation, and downward pressure. This can be especially problematic for hand-held inspection tools where none of these parameters is mechanically controlled. As a result, data can vary drastically from one inspection to the next, from one technician to the next, and even from one sweep to the next. Structural health monitoring (SHM) offers the promise of a paradigm shift from schedule-driven maintenance to condition-based maintenance (CBM) of assets. Sensors embedded permanently in aircraft safety critical structures that can monitor damage can provide for improved reliability and streamlining of aircraft maintenance. Early detection of damage such as fatigue crack initiation can improve personnel safety and prolong service life. This paper presents the testing of an acousto-ultrasonic piezoelectric sensor based structural health monitoring system for real-time monitoring of fatigue cracks and disbonds in bonded repairs. The system utilizes a network of distributed miniature piezoelectric sensors/actuators embedded on a thin dielectric carrier film, to query, monitor and evaluate the condition of a structure. The sensor layers are extremely flexible and can be integrated with any type of metal or composite structure. Diagnostic signals obtained from a structure during structural monitoring are processed by a portable diagnostic unit. With appropriate diagnostic software, the signals can be analyzed to ascertain the integrity of the structure being monitored. Details on the system, its integration and examples of detection of fatigue crack and disbond growth and quantification for bonded repairs will be presented here.
Muinde, R K; Kiinyukia, C; Rombo, G O; Muoki, M A
2012-12-01
To determine the microbial load in food, examination of safety measures and possibility of implementing an Hazard Analysis Critical Control Points (HACCP) system. The target population for this study consisted of restaurants owners in Thika. Municipality (n = 30). Simple randomsamples of restaurantswere selected on a systematic sampling method of microbial analysis in cooked, non-cooked, raw food and water sanitation in the selected restaurants. Two hundred and ninety eight restaurants within Thika Municipality were selected. Of these, 30 were sampled for microbiological testing. From the study, 221 (74%) of the restaurants were ready to eat establishments where food was prepared early enough to hold and only 77(26%) of the total restaurants, customers made an order of food they wanted. 118(63%) of the restaurant operators/staff had knowledge on quality control on food safety measures, 24 (8%) of the restaurants applied these knowledge while 256 (86%) of the restaurants staff showed that food contains ingredients that were hazard if poorly handled. 238 (80%) of the resultants used weighing and sorting of food materials, 45 (15%) used preservation methods and the rest used dry foods as critical control points on food safety measures. The study showed that there was need for implementation of Hazard Analysis Critical Control Points (HACCP) system to enhance food safety. Knowledge of HACCP was very low with 89 (30%) of the restaurants applying some of quality measures to the food production process systems. There was contamination with Coliforms, Escherichia coli and Staphylococcus aureus microbial though at very low level. The means of Coliforms, Escherichia coli and Staphylococcus aureas microbial in sampled food were 9.7 x 103CFU/gm, 8.2 x 103 CFU/gm and 5.4 x 103 CFU/gm respectively with Coliforms taking the highest mean.
Evolution of safety-critical requirements post-launch
NASA Technical Reports Server (NTRS)
Lutz, R. R.; Mikulski, I. C.
2001-01-01
This paper reports the results of a small study of requirements changes to the onboard software of three spacecraft subsequent to launch. Only those requirement changes that resulted from post-launch anoma-lies (i.e., during operations) were of interest here, since the goal was to better understand the relation-ship between critical anomalies during operations and how safety-critical requirements evolve. The results of the study were surprising in that anomaly-driven, post-launch requirements changes were rarely due to previous requirements having been incorrect. Instead, changes involved new requirements (1) for the software to handle rare events or (2) for the software to compensate for hardware failures or limitations. The prevalence of new requirements as a result of post-launch anomalies suggests a need for increased requirements-engineering support of maintenance activities in these systems. The results also confirm both the difficulty and the benefits of pursuing requirements completeness, especially in terms of fault tolerance, during development of critical systems.
Principles and Benefits of Explicitly Designed Medical Device Safety Architecture.
Larson, Brian R; Jones, Paul; Zhang, Yi; Hatcliff, John
The complexity of medical devices and the processes by which they are developed pose considerable challenges to producing safe designs and regulatory submissions that are amenable to effective reviews. Designing an appropriate and clearly documented architecture can be an important step in addressing this complexity. Best practices in medical device design embrace the notion of a safety architecture organized around distinct operation and safety requirements. By explicitly separating many safety-related monitoring and mitigation functions from operational functionality, the aspects of a device most critical to safety can be localized into a smaller and simpler safety subsystem, thereby enabling easier verification and more effective reviews of claims that causes of hazardous situations are detected and handled properly. This article defines medical device safety architecture, describes its purpose and philosophy, and provides an example. Although many of the presented concepts may be familiar to those with experience in realization of safety-critical systems, this article aims to distill the essence of the approach and provide practical guidance that can potentially improve the quality of device designs and regulatory submissions.
Partial least squares models for hyperspectral contaminant detection
USDA-ARS?s Scientific Manuscript database
The United States of America food supply is one of the safest in the world. However, it is not free of pathogens. For the poultry industry, the Food Safety Inspection Service (FSIS) has regulatory responsiblity for food safety and has established a hazard analysis, critical control point system (HAC...
ERIC Educational Resources Information Center
Jones, Rebecca
1998-01-01
In response to growing threat of food-borne illness, the federal government launched the Food Safety Initiative. A key element is the Hazard Analysis Critical Control Points system (HACCP), designed to make everyone in the food-delivery chain responsible for ensuring a safe food supply. The Food and Drug Administration also announced a beef…
Formal verification of software-based medical devices considering medical guidelines.
Daw, Zamira; Cleaveland, Rance; Vetter, Marcus
2014-01-01
Software-based devices have increasingly become an important part of several clinical scenarios. Due to their critical impact on human life, medical devices have very strict safety requirements. It is therefore necessary to apply verification methods to ensure that the safety requirements are met. Verification of software-based devices is commonly limited to the verification of their internal elements without considering the interaction that these elements have with other devices as well as the application environment in which they are used. Medical guidelines define clinical procedures, which contain the necessary information to completely verify medical devices. The objective of this work was to incorporate medical guidelines into the verification process in order to increase the reliability of the software-based medical devices. Medical devices are developed using the model-driven method deterministic models for signal processing of embedded systems (DMOSES). This method uses unified modeling language (UML) models as a basis for the development of medical devices. The UML activity diagram is used to describe medical guidelines as workflows. The functionality of the medical devices is abstracted as a set of actions that is modeled within these workflows. In this paper, the UML models are verified using the UPPAAL model-checker. For this purpose, a formalization approach for the UML models using timed automaton (TA) is presented. A set of requirements is verified by the proposed approach for the navigation-guided biopsy. This shows the capability for identifying errors or optimization points both in the workflow and in the system design of the navigation device. In addition to the above, an open source eclipse plug-in was developed for the automated transformation of UML models into TA models that are automatically verified using UPPAAL. The proposed method enables developers to model medical devices and their clinical environment using clinical workflows as one UML diagram. Additionally, the system design can be formally verified automatically.
Steege, Rosalind; Taegtmeyer, Miriam; McCollum, Rosalind; Hawkins, Kate; Ormel, Hermen; Kok, Maryse; Rashid, Sabina; Otiso, Lilian; Sidat, Mohsin; Chikaphupha, Kingsley; Datiko, Daniel Gemechu; Ahmed, Rukhsana; Tolhurst, Rachel; Gomez, Woedem; Theobald, Sally
2018-05-05
Close-to-community (CTC) providers have been identified as a key cadre to progress universal health coverage and address inequities in health service provision due to their embedded position within communities. CTC providers both work within, and are subject to, the gender norms at community level but may also have the potential to alter them. This paper synthesises current evidence on gender and CTC providers and the services they deliver. This study uses a two-stage exploratory approach drawing upon qualitative research from the six countries (Bangladesh, Indonesia, Ethiopia, Kenya, Malawi, Mozambique) that were part of the REACHOUT consortium. This research took place from 2013 to 2014. This was followed by systematic review that took place from January-September 2017, using critical interpretive synthesis methodology. This review included 58 papers from the literature. The resulting findings from both stages informed the development of a conceptual framework. We present the holistic conceptual framework to show how gender roles and relations shape CTC provider experience at the individual, community, and health system levels. The evidence presented highlights the importance of safety and mobility at the community level. At the individual level, influence of family and intra-household dynamics are of importance. Important at the health systems level, are career progression and remuneration. We present suggestions for how the role of a CTC provider can, with the right support, be an empowering experience. Key priorities for policymakers to promote gender equity in this cadre include: safety and well-being, remuneration, and career progression opportunities. Gender roles and relations shape CTC provider experiences across multiple levels of the health system. To strengthen the equity and efficiency of CTC programmes gender dynamics should be considered by policymakers and implementers during both the conceptualisation and implementation of CTC programmes. Copyright © 2018. Published by Elsevier Ltd.
Instructional games and activities for criticality safety training
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bullard, B.; McBride, J.
1993-01-01
During the past several years, the Training and Management Systems Division (TMSD) staff of Oak Ridge Institute for Science and Education (ORISE) has designed and developed nuclear criticality safety (NCS) training programs that focus on high trainee involvement through the use of instructional games and activities. This paper discusses the instructional game, initial considerations for developing games, advantages and limitations of games, and how games may be used in developing and implementing NCS training. It also provides examples of the various instructional games and activities used in separate courses designed for Martin Marietta Energy Systems (MMES's) supervisors and U.S. Nuclearmore » Regulatory Commission (NRC) fuel facility inspectors.« less
Weinfurt, Kevin P; Hernandez, Adrian F; Coronado, Gloria D; DeBar, Lynn L; Dember, Laura M; Green, Beverly B; Heagerty, Patrick J; Huang, Susan S; James, Kathryn T; Jarvik, Jeffrey G; Larson, Eric B; Mor, Vincent; Platt, Richard; Rosenthal, Gary E; Septimus, Edward J; Simon, Gregory E; Staman, Karen L; Sugarman, Jeremy; Vazquez, Miguel; Zatzick, Douglas; Curtis, Lesley H
2017-09-18
The clinical research enterprise is not producing the evidence decision makers arguably need in a timely and cost effective manner; research currently involves the use of labor-intensive parallel systems that are separate from clinical care. The emergence of pragmatic clinical trials (PCTs) poses a possible solution: these large-scale trials are embedded within routine clinical care and often involve cluster randomization of hospitals, clinics, primary care providers, etc. Interventions can be implemented by health system personnel through usual communication channels and quality improvement infrastructure, and data collected as part of routine clinical care. However, experience with these trials is nascent and best practices regarding design operational, analytic, and reporting methodologies are undeveloped. To strengthen the national capacity to implement cost-effective, large-scale PCTs, the Common Fund of the National Institutes of Health created the Health Care Systems Research Collaboratory (Collaboratory) to support the design, execution, and dissemination of a series of demonstration projects using a pragmatic research design. In this article, we will describe the Collaboratory, highlight some of the challenges encountered and solutions developed thus far, and discuss remaining barriers and opportunities for large-scale evidence generation using PCTs. A planning phase is critical, and even with careful planning, new challenges arise during execution; comparisons between arms can be complicated by unanticipated changes. Early and ongoing engagement with both health care system leaders and front-line clinicians is critical for success. There is also marked uncertainty when applying existing ethical and regulatory frameworks to PCTS, and using existing electronic health records for data capture adds complexity.
Sens, Brigitte
2010-01-01
The concept of general process orientation as an instrument of organisation development is the core principle of quality management philosophy, i.e. the learning organisation. Accordingly, prestigious quality awards and certification systems focus on process configuration and continual improvement. In German health care organisations, particularly in hospitals, this general process orientation has not been widely implemented yet - despite enormous change dynamics and the requirements of both quality and economic efficiency of health care processes. But based on a consistent process architecture that considers key processes as well as management and support processes, the strategy of excellent health service provision including quality, safety and transparency can be realised in daily operative work. The core elements of quality (e.g., evidence-based medicine), patient safety and risk management, environmental management, health and safety at work can be embedded in daily health care processes as an integrated management system (the "all in one system" principle). Sustainable advantages and benefits for patients, staff, and the organisation will result: stable, high-quality, efficient, and indicator-based health care processes. Hospitals with their broad variety of complex health care procedures should now exploit the full potential of total process orientation. Copyright © 2010. Published by Elsevier GmbH.
Application of SAE ARP4754A to Flight Critical Systems
NASA Technical Reports Server (NTRS)
Peterson, Eric M.
2015-01-01
This report documents applications of ARP4754A to the development of modern computer-based (i.e., digital electronics, software and network-based) aircraft systems. This study is to offer insight and provide educational value relative to the guidelines in ARP4754A and provide an assessment of the current state-of-the- practice within industry and regulatory bodies relative to development assurance for complex and safety-critical computer-based aircraft systems.
Autonomous Flight Safety System
NASA Technical Reports Server (NTRS)
Ferrell, Bob; Santuro, Steve; Simpson, James; Zoerner, Roger; Bull, Barton; Lanzi, Jim
2004-01-01
Autonomous Flight Safety System (AFSS) is an independent flight safety system designed for small to medium sized expendable launch vehicles launching from or needing range safety protection while overlying relatively remote locations. AFSS replaces the need for a man-in-the-loop to make decisions for flight termination. AFSS could also serve as the prototype for an autonomous manned flight crew escape advisory system. AFSS utilizes onboard sensors and processors to emulate the human decision-making process using rule-based software logic and can dramatically reduce safety response time during critical launch phases. The Range Safety flight path nominal trajectory, its deviation allowances, limit zones and other flight safety rules are stored in the onboard computers. Position, velocity and attitude data obtained from onboard global positioning system (GPS) and inertial navigation system (INS) sensors are compared with these rules to determine the appropriate action to ensure that people and property are not jeopardized. The final system will be fully redundant and independent with multiple processors, sensors, and dead man switches to prevent inadvertent flight termination. AFSS is currently in Phase III which includes updated algorithms, integrated GPS/INS sensors, large scale simulation testing and initial aircraft flight testing.
A Critical Analysis of Job-Embedded Professional Learning within a Distributed Leadership Framework
ERIC Educational Resources Information Center
Campoli, Ashley Jimerson
2011-01-01
Leadership style and professional learning have been linked to student achievement. Studies have linked leadership styles such as distributed leadership to job-embedded professional learning. However, research is mixed when these two constructs are related to student achievement. This study evaluated the relationship between distributed…
Embedding Research-Based Learning Early in the Undergraduate Geography Curriculum
ERIC Educational Resources Information Center
Walkington, Helen; Griffin, Amy L.; Keys-Mathews, Lisa; Metoyer, Sandra K.; Miller, Wendy E.; Baker, Richard; France, Derek
2011-01-01
This article considers the rationale for embedding research and enquiry skills early in the undergraduate geography curriculum and for making these skills explicit to students. A survey of 52 international geography faculty identified critical thinking, framing research questions, reflectivity and creativity as the most challenging research skills…
Formal Foundations for Hierarchical Safety Cases
NASA Technical Reports Server (NTRS)
Denney, Ewen; Pai, Ganesh; Whiteside, Iain
2015-01-01
Safety cases are increasingly being required in many safety-critical domains to assure, using structured argumentation and evidence, that a system is acceptably safe. However, comprehensive system-wide safety arguments present appreciable challenges to develop, understand, evaluate, and manage, partly due to the volume of information that they aggregate, such as the results of hazard analysis, requirements analysis, testing, formal verification, and other engineering activities. Previously, we have proposed hierarchical safety cases, hicases, to aid the comprehension of safety case argument structures. In this paper, we build on a formal notion of safety case to formalise the use of hierarchy as a structuring technique, and show that hicases satisfy several desirable properties. Our aim is to provide a formal, theoretical foundation for safety cases. In particular, we believe that tools for high assurance systems should be granted similar assurance to the systems to which they are applied. To this end, we formally specify and prove the correctness of key operations for constructing and managing hicases, which gives the specification for implementing hicases in AdvoCATE, our toolset for safety case automation. We motivate and explain the theory with the help of a simple running example, extracted from a real safety case and developed using AdvoCATE.
Proceedings of the Second NASA Formal Methods Symposium
NASA Technical Reports Server (NTRS)
Munoz, Cesar (Editor)
2010-01-01
This publication contains the proceedings of the Second NASA Formal Methods Symposium sponsored by the National Aeronautics and Space Administration and held in Washington D.C. April 13-15, 2010. Topics covered include: Decision Engines for Software Analysis using Satisfiability Modulo Theories Solvers; Verification and Validation of Flight-Critical Systems; Formal Methods at Intel -- An Overview; Automatic Review of Abstract State Machines by Meta Property Verification; Hardware-independent Proofs of Numerical Programs; Slice-based Formal Specification Measures -- Mapping Coupling and Cohesion Measures to Formal Z; How Formal Methods Impels Discovery: A Short History of an Air Traffic Management Project; A Machine-Checked Proof of A State-Space Construction Algorithm; Automated Assume-Guarantee Reasoning for Omega-Regular Systems and Specifications; Modeling Regular Replacement for String Constraint Solving; Using Integer Clocks to Verify the Timing-Sync Sensor Network Protocol; Can Regulatory Bodies Expect Efficient Help from Formal Methods?; Synthesis of Greedy Algorithms Using Dominance Relations; A New Method for Incremental Testing of Finite State Machines; Verification of Faulty Message Passing Systems with Continuous State Space in PVS; Phase Two Feasibility Study for Software Safety Requirements Analysis Using Model Checking; A Prototype Embedding of Bluespec System Verilog in the PVS Theorem Prover; SimCheck: An Expressive Type System for Simulink; Coverage Metrics for Requirements-Based Testing: Evaluation of Effectiveness; Software Model Checking of ARINC-653 Flight Code with MCP; Evaluation of a Guideline by Formal Modelling of Cruise Control System in Event-B; Formal Verification of Large Software Systems; Symbolic Computation of Strongly Connected Components Using Saturation; Towards the Formal Verification of a Distributed Real-Time Automotive System; Slicing AADL Specifications for Model Checking; Model Checking with Edge-valued Decision Diagrams; and Data-flow based Model Analysis.
Formal Modeling and Analysis of a Preliminary Small Aircraft Transportation System (SATS)Concept
NASA Technical Reports Server (NTRS)
Carrreno, Victor A.; Gottliebsen, Hanne; Butler, Ricky; Kalvala, Sara
2004-01-01
New concepts for automating air traffic management functions at small non-towered airports raise serious safety issues associated with the software implementations and their underlying key algorithms. The criticality of such software systems necessitates that strong guarantees of the safety be developed for them. In this paper we present a formal method for modeling and verifying such systems using the PVS theorem proving system. The method is demonstrated on a preliminary concept of operation for the Small Aircraft Transportation System (SATS) project at NASA Langley.
Glass, Robert S.; Clarke, Jr., Willis L.; Ciarlo, Dino R.
1994-01-01
A corrosion sensor array incorporating individual elements for measuring various elements and ions, such as chloride, sulfide, copper, hydrogen (pH), etc. and elements for evaluating the instantaneous corrosion properties of structural materials. The exact combination and number of elements measured or monitored would depend upon the environmental conditions and materials used which are subject to corrosive effects. Such a corrosion monitoring system embedded in or mounted on a structure exposed to the environment would serve as an early warning system for the onset of severe corrosion problems for the structure, thus providing a safety factor as well as economic factors. The sensor array is accessed to an electronics/computational system, which provides a means for data collection and analysis.
Glass, R.S.; Clarke, W.L. Jr.; Ciarlo, D.R.
1994-04-26
A corrosion sensor array is described incorporating individual elements for measuring various elements and ions, such as chloride, sulfide, copper, hydrogen (pH), etc. and elements for evaluating the instantaneous corrosion properties of structural materials. The exact combination and number of elements measured or monitored would depend upon the environmental conditions and materials used which are subject to corrosive effects. Such a corrosion monitoring system embedded in or mounted on a structure exposed to the environment would serve as an early warning system for the onset of severe corrosion problems for the structure, thus providing a safety factor as well as economic factors. The sensor array is accessed to an electronics/computational system, which provides a means for data collection and analysis. 7 figures.
Method for monitoring environmental and corrosion
Glass, Robert S.; Clarke, Jr., Willis L.; Ciarlo, Dino R.
1995-01-01
A corrosion sensor array incorporating individual elements for measuring various elements and ions, such as chloride, sulfide, copper, hydrogen (pH), etc. and elements for evaluating the instantaneous corrosion properties of structural materials. The exact combination and number of elements measured or monitored would depend upon the environmental conditions and materials used which are subject to corrosive effects. Such a corrosion monitoring system embedded in or mounted on a structure exposed to the environment would serve as an early warning system for the onset of severe corrosion problems for the structure, thus providing a safety factor as well as economic factors. The sensor array is accessed to an electronics/computational system, which provides a means for data collection and analysis.
NASA Technical Reports Server (NTRS)
Milos, Frank S.; Watters, David G.; Pallix, Joan B.; Bahr, Alfred J.; Huestis, David L.; Arnold, Jim (Technical Monitor)
2001-01-01
Health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles in order to reduce life cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to develop inspection and health management technologies for thermal protection systems. This paper summarizes a joint project between NASA Ames and SRI International to develop 'SensorTags,' radio frequency identification devices coupled with event-recording sensors, that can be embedded in the thermal protection system to monitor temperature or other quantities of interest. Two prototype SensorTag designs containing thermal fuses to indicate a temperature overlimit are presented and discussed.
Kanter, Robert K
2012-09-01
To empirically describe the integration of pediatric disaster services into regional systems of care after the April 27, 2011, tornado in Tuscaloosa, Alabama, a community with no pediatric emergency department or pediatric intensive care unit and few pediatric subspecialists. Data were obtained in interviews with key informants including professional staff and managers from public health and emergency management agencies, prehospital emergency medical services, fire departments, hospital nurses, physicians, and the trauma program coordinator. A single hospital in Tuscaloosa served 800 patients on the night of the tornado. More than 100 of these patients were children, including more than 20 with critical injuries. Many children were unaccompanied and unidentified on arrival. Resuscitation and stabilization were performed by nonpediatric prehospital and emergency department staff. More than 20 children were secondarily transported to the nearest children's hospital an hour's drive away under the care of nonpediatric local emergency medical services providers. No preventable adverse events were identified in the resuscitation and secondary transport phases of care. Stockpiled supplies and equipment were adequate to serve the needs of the disaster victims, including the children. Essential aspects of preparation include pediatric-specific clinical skills, supplies and equipment, operational disaster plans, and interagency practice embedded in everyday work. Opportunities for improvement identified include more timely response to warnings, improved practices for identifying unaccompanied children, and enhanced child safety in shelters. Successful responses depended on integration of pediatric services into regional systems of care. Copyright © 2012 Mosby, Inc. All rights reserved.
Assuring NASA's Safety and Mission Critical Software
NASA Technical Reports Server (NTRS)
Deadrick, Wesley
2015-01-01
What is IV&V? Independent Verification and Validation (IV&V) is an objective examination of safety and mission critical software processes and products. Independence: 3 Key parameters: Technical Independence; Managerial Independence; Financial Independence. NASA IV&V perspectives: Will the system's software: Do what it is supposed to do?; Not do what it is not supposed to do?; Respond as expected under adverse conditions?. Systems Engineering: Determines if the right system has been built and that it has been built correctly. IV&V Technical Approaches: Aligned with IEEE 1012; Captured in a Catalog of Methods; Spans the full project lifecycle. IV&V Assurance Strategy: The IV&V Project's strategy for providing mission assurance; Assurance Strategy is driven by the specific needs of an individual project; Implemented via an Assurance Design; Communicated via Assurance Statements.
Liu, Rui; Chen, Pei; Aihara, Kazuyuki; Chen, Luonan
2015-01-01
Identifying early-warning signals of a critical transition for a complex system is difficult, especially when the target system is constantly perturbed by big noise, which makes the traditional methods fail due to the strong fluctuations of the observed data. In this work, we show that the critical transition is not traditional state-transition but probability distribution-transition when the noise is not sufficiently small, which, however, is a ubiquitous case in real systems. We present a model-free computational method to detect the warning signals before such transitions. The key idea behind is a strategy: “making big noise smaller” by a distribution-embedding scheme, which transforms the data from the observed state-variables with big noise to their distribution-variables with small noise, and thus makes the traditional criteria effective because of the significantly reduced fluctuations. Specifically, increasing the dimension of the observed data by moment expansion that changes the system from state-dynamics to probability distribution-dynamics, we derive new data in a higher-dimensional space but with much smaller noise. Then, we develop a criterion based on the dynamical network marker (DNM) to signal the impending critical transition using the transformed higher-dimensional data. We also demonstrate the effectiveness of our method in biological, ecological and financial systems. PMID:26647650
Control of Suspect/Counterfeit and Defective Items
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheriff, Marnelle L.
2013-09-03
This procedure implements portions of the requirements of MSC-MP-599, Quality Assurance Program Description. It establishes the Mission Support Alliance (MSA) practices for minimizing the introduction of and identifying, documenting, dispositioning, reporting, controlling, and disposing of suspect/counterfeit and defective items (S/CIs). employees whose work scope relates to Safety Systems (i.e., Safety Class [SC] or Safety Significant [SS] items), non-safety systems and other applications (i.e., General Service [GS]) where engineering has determined that their use could result in a potential safety hazard. MSA implements an effective Quality Assurance (QA) Program providing a comprehensive network of controls and verification providing defense-in-depth by preventingmore » the introduction of S/CIs through the design, procurement, construction, operation, maintenance, and modification of processes. This procedure focuses on those safety systems, and other systems, including critical load paths of lifting equipment, where the introduction of S/CIs would have the greatest potential for creating unsafe conditions.« less
Towards sensor array materials: can failure be delayed?
Mekid, Samir; Saheb, Nouari; Khan, Shafique M A; Qureshi, Khurram K
2015-01-01
Further to prior development in enhancing structural health using smart materials, an innovative class of materials characterized by the ability to feel senses like humans, i.e. ‘nervous materials’, is discussed. Designed at all scales, these materials will enhance personnel and public safety, and secure greater reliability of products. Materials may fail suddenly, but any system wishes that failure is known in good time and delayed until safe conditions are reached. Nervous materials are expected to be the solution to this statement. This new class of materials is based on the novel concept of materials capable of feeling multiple structural and external stimuli, e.g. stress, force, pressure and temperature, while feeding information back to a controller for appropriate real-time action. The strain–stress state is developed in real time with the identified and characterized source of stimulus, with optimized time response to retrieve initial specified conditions, e.g. shape and strength. Sensors are volumetrically embedded and distributed, emulating the human nervous system. Immediate applications are in aircraft, cars, nuclear energy and robotics. Such materials will reduce maintenance costs, detect initial failures and delay them with self-healing. This article reviews the common aspects and challenges surrounding this new class of materials with types of sensors to be embedded seamlessly or inherently, including appropriate embedding manufacturing techniques with modeling and simulation methods. PMID:27877794
Towards sensor array materials: can failure be delayed?
NASA Astrophysics Data System (ADS)
Mekid, Samir; Saheb, Nouari; Khan, Shafique M. A.; Qureshi, Khurram K.
2015-06-01
Further to prior development in enhancing structural health using smart materials, an innovative class of materials characterized by the ability to feel senses like humans, i.e. ‘nervous materials’, is discussed. Designed at all scales, these materials will enhance personnel and public safety, and secure greater reliability of products. Materials may fail suddenly, but any system wishes that failure is known in good time and delayed until safe conditions are reached. Nervous materials are expected to be the solution to this statement. This new class of materials is based on the novel concept of materials capable of feeling multiple structural and external stimuli, e.g. stress, force, pressure and temperature, while feeding information back to a controller for appropriate real-time action. The strain-stress state is developed in real time with the identified and characterized source of stimulus, with optimized time response to retrieve initial specified conditions, e.g. shape and strength. Sensors are volumetrically embedded and distributed, emulating the human nervous system. Immediate applications are in aircraft, cars, nuclear energy and robotics. Such materials will reduce maintenance costs, detect initial failures and delay them with self-healing. This article reviews the common aspects and challenges surrounding this new class of materials with types of sensors to be embedded seamlessly or inherently, including appropriate embedding manufacturing techniques with modeling and simulation methods.
Novel Concepts for Radiation Shielding Materials
NASA Technical Reports Server (NTRS)
Oliva-Buisson, Yvette J.
2014-01-01
It is critical that safety factors be maximized with respect to long duration, extraterrestrial space flight. Any significant improvement in radiation protection will be critical in ensuring the safety of crew and hardware on such missions. The project goal is to study novel concepts for radiation shielding materials that can be used for long-duration space missions. As part of this project we will investigate the use of thin films for the evaluation of a containment system that can retain liquid hydrogen and provide the necessary hydrogen density for effective shielding.
Leveraging Embedded Training Systems to Build Higher Level Cognitive Skills in Warfighters
2009-10-01
is not just passive, waiting for key information to be presented, but is an active process . The information that is available to military pilots...train situation awareness (SA) skills and knowledge in military settings. SA is the key cognitive construct upon which decision making rests and one...task analyses in the military domain settings that reveal the critical SA elements for a given warfighter role and the challenges they must contend
A Microbial Assessment Scheme to measure microbial performance of Food Safety Management Systems.
Jacxsens, L; Kussaga, J; Luning, P A; Van der Spiegel, M; Devlieghere, F; Uyttendaele, M
2009-08-31
A Food Safety Management System (FSMS) implemented in a food processing industry is based on Good Hygienic Practices (GHP), Hazard Analysis Critical Control Point (HACCP) principles and should address both food safety control and assurance activities in order to guarantee food safety. One of the most emerging challenges is to assess the performance of a present FSMS. The objective of this work is to explain the development of a Microbial Assessment Scheme (MAS) as a tool for a systematic analysis of microbial counts in order to assess the current microbial performance of an implemented FSMS. It is assumed that low numbers of microorganisms and small variations in microbial counts indicate an effective FSMS. The MAS is a procedure that defines the identification of critical sampling locations, the selection of microbiological parameters, the assessment of sampling frequency, the selection of sampling method and method of analysis, and finally data processing and interpretation. Based on the MAS assessment, microbial safety level profiles can be derived, indicating which microorganisms and to what extent they contribute to food safety for a specific food processing company. The MAS concept is illustrated with a case study in the pork processing industry, where ready-to-eat meat products are produced (cured, cooked ham and cured, dried bacon).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Sangkeun; Chen, Liangzhe; Duan, Sisi
Abstract Critical Infrastructures (CIs) such as energy, water, and transportation are complex networks that are crucial for sustaining day-to-day commodity flows vital to national security, economic stability, and public safety. The nature of these CIs is such that failures caused by an extreme weather event or a man-made incident can trigger widespread cascading failures, sending ripple effects at regional or even national scales. To minimize such effects, it is critical for emergency responders to identify existing or potential vulnerabilities within CIs during such stressor events in a systematic and quantifiable manner and take appropriate mitigating actions. We present here amore » novel critical infrastructure monitoring and analysis system named URBAN-NET. The system includes a software stack and tools for monitoring CIs, pre-processing data, interconnecting multiple CI datasets as a heterogeneous network, identifying vulnerabilities through graph-based topological analysis, and predicting consequences based on what-if simulations along with visualization. As a proof-of-concept, we present several case studies to show the capabilities of our system. We also discuss remaining challenges and future work.« less
Initial experience using the rigid forceps technique to remove wall-embedded IVC filters.
Avery, Allan; Stephens, Maximilian; Redmond, Kendal; Harper, John
2015-06-01
Severely tilted and embedded inferior vena cava (IVC) filters remain the most challenging IVC filters to remove. Heavy endothelialisation over the filter hook can prevent engagement with standard snare and cone recovery techniques. The rigid forceps technique offers a way to dissect the endothelial cap and reliably retrieve severely tilted and embedded filters. By developing this technique, failed IVC retrieval rates can be significantly reduced and the optimum safety profile offered by temporary filters can be achieved. We present our initial experience with the rigid forceps technique described by Stavropoulos et al. for removing wall-embedded IVC filters. We retrospectively reviewed the medical imaging and patient records of all patients who underwent a rigid forceps filter removal over a 22-month period across two tertiary referral institutions. The rigid forceps technique had a success rate of 85% (11/13) for IVC filter removals. All filters in the series showed evidence of filter tilt and embedding of the filter hook into the IVC wall. Average filter tilt from the Z-axis was 19 degrees (range 8-56). Filters observed in the case study were either Bard G2X (n = 6) or Cook Celect (n = 7). Average filter dwell time was 421 days (range 47-1053). There were no major complications observed. The rigid forceps technique can be readily emulated and is a safe and effective technique to remove severely tilted and embedded IVC filters. The development of this technique across both institutions has increased the successful filter removal rate, with perceived benefits to the safety profile of our IVC filter programme. © 2015 The Royal Australian and New Zealand College of Radiologists.
Ross, Joseph S; Bates, Jonathan; Parzynski, Craig S; Akar, Joseph G; Curtis, Jeptha P; Desai, Nihar R; Freeman, James V; Gamble, Ginger M; Kuntz, Richard; Li, Shu-Xia; Marinac-Dabic, Danica; Masoudi, Frederick A; Normand, Sharon-Lise T; Ranasinghe, Isuru; Shaw, Richard E; Krumholz, Harlan M
2017-01-01
Background Machine learning methods may complement traditional analytic methods for medical device surveillance. Methods and results Using data from the National Cardiovascular Data Registry for implantable cardioverter–defibrillators (ICDs) linked to Medicare administrative claims for longitudinal follow-up, we applied three statistical approaches to safety-signal detection for commonly used dual-chamber ICDs that used two propensity score (PS) models: one specified by subject-matter experts (PS-SME), and the other one by machine learning-based selection (PS-ML). The first approach used PS-SME and cumulative incidence (time-to-event), the second approach used PS-SME and cumulative risk (Data Extraction and Longitudinal Trend Analysis [DELTA]), and the third approach used PS-ML and cumulative risk (embedded feature selection). Safety-signal surveillance was conducted for eleven dual-chamber ICD models implanted at least 2,000 times over 3 years. Between 2006 and 2010, there were 71,948 Medicare fee-for-service beneficiaries who received dual-chamber ICDs. Cumulative device-specific unadjusted 3-year event rates varied for three surveyed safety signals: death from any cause, 12.8%–20.9%; nonfatal ICD-related adverse events, 19.3%–26.3%; and death from any cause or nonfatal ICD-related adverse event, 27.1%–37.6%. Agreement among safety signals detected/not detected between the time-to-event and DELTA approaches was 90.9% (360 of 396, k=0.068), between the time-to-event and embedded feature-selection approaches was 91.7% (363 of 396, k=−0.028), and between the DELTA and embedded feature selection approaches was 88.1% (349 of 396, k=−0.042). Conclusion Three statistical approaches, including one machine learning method, identified important safety signals, but without exact agreement. Ensemble methods may be needed to detect all safety signals for further evaluation during medical device surveillance. PMID:28860874
Intelligent monitoring of critical pathological events during anesthesia.
Gohil, Bhupendra; Gholamhhosseini, Hamid; Harrison, Michael J; Lowe, Andrew; Al-Jumaily, Ahmed
2007-01-01
Expert algorithms in the field of intelligent patient monitoring have rapidly revolutionized patient care thereby improving patient safety. Patient monitoring during anesthesia requires cautious attention by anesthetists who are monitoring many modalities, diagnosing clinically critical events and performing patient management tasks simultaneously. The mishaps that occur during day-to-day anesthesia causing disastrous errors in anesthesia administration were classified and studied by Reason [1]. Human errors in anesthesia account for 82% of the preventable mishaps [2]. The aim of this paper is to develop a clinically useful diagnostic alarm system for detecting critical events during anesthesia administration. The development of an expert diagnostic alarm system called ;RT-SAAM' for detecting critical pathological events in the operating theatre is presented. This system provides decision support to the anesthetist by presenting the diagnostic results on an integrative, ergonomic display and thus enhancing patient safety. The performance of the system was validated through a series of offline and real-time testing in the operation theatre. When detecting absolute hypovolaemia (AHV), moderate level of agreement was observed between RT-SAAM and the human expert (anesthetist) during surgical procedures. RT-SAAM is a clinically useful diagnostic tool which can be easily modified for diagnosing additional critical pathological events like relative hypovolaemia, fall in cardiac output, sympathetic response and malignant hyperpyrexia during surgical procedures. RT-SAAM is currently being tested at the Auckland City Hospital with ethical approval from the local ethics committees.
Proceedings of the Nuclear Criticality Technology Safety Workshop
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rene G. Sanchez
1998-04-01
This document contains summaries of most of the papers presented at the 1995 Nuclear Criticality Technology Safety Project (NCTSP) meeting, which was held May 16 and 17 at San Diego, Ca. The meeting was broken up into seven sessions, which covered the following topics: (1) Criticality Safety of Project Sapphire; (2) Relevant Experiments For Criticality Safety; (3) Interactions with the Former Soviet Union; (4) Misapplications and Limitations of Monte Carlo Methods Directed Toward Criticality Safety Analyses; (5) Monte Carlo Vulnerabilities of Execution and Interpretation; (6) Monte Carlo Vulnerabilities of Representation; and (7) Benchmark Comparisons.
GPM Timeline Inhibits For IT Processing
NASA Technical Reports Server (NTRS)
Dion, Shirley K.
2014-01-01
The Safety Inhibit Timeline Tool was created as one approach to capturing and understanding inhibits and controls from IT through launch. Global Precipitation Measurement (GPM) Mission, which launched from Japan in March 2014, was a joint mission under a partnership between the National Aeronautics and Space Administration (NASA) and the Japan Aerospace Exploration Agency (JAXA). GPM was one of the first NASA Goddard in-house programs that extensively used software controls. Using this tool during the GPM buildup allowed a thorough review of inhibit and safety critical software design for hazardous subsystems such as the high gain antenna boom, solar array, and instrument deployments, transmitter turn-on, propulsion system release, and instrument radar turn-on. The GPM safety team developed a methodology to document software safety as part of the standard hazard report. As a result of this process, a new tool safety inhibit timeline was created for management of inhibits and their controls during spacecraft buildup and testing during IT at GSFC and at the launch range in Japan. The Safety Inhibit Timeline Tool was a pathfinder approach for reviewing software that controls the electrical inhibits. The Safety Inhibit Timeline Tool strengthens the Safety Analysts understanding of the removal of inhibits during the IT process with safety critical software. With this tool, the Safety Analyst can confirm proper safe configuration of a spacecraft during each IT test, track inhibit and software configuration changes, and assess software criticality. In addition to understanding inhibits and controls during IT, the tool allows the Safety Analyst to better communicate to engineers and management the changes in inhibit states with each phase of hardware and software testing and the impact of safety risks. Lessons learned from participating in the GPM campaign at NASA and JAXA will be discussed during this session.
Quantifying Pilot Contribution to Flight Safety during Drive Shaft Failure
NASA Technical Reports Server (NTRS)
Kramer, Lynda J.; Etherington, Tim; Last, Mary Carolyn; Bailey, Randall E.; Kennedy, Kellie D.
2017-01-01
Accident statistics cite the flight crew as a causal factor in over 60% of large transport aircraft fatal accidents. Yet, a well-trained and well-qualified pilot is acknowledged as the critical center point of aircraft systems safety and an integral safety component of the entire commercial aviation system. The latter statement, while generally accepted, cannot be verified because little or no quantitative data exists on how and how many accidents/incidents are averted by crew actions. A joint NASA/FAA high-fidelity motion-base simulation experiment specifically addressed this void by collecting data to quantify the human (pilot) contribution to safety-of-flight and the methods they use in today's National Airspace System. A human-in-the-loop test was conducted using the FAA's Oklahoma City Flight Simulation Branch Level D-certified B-737-800 simulator to evaluate the pilot's contribution to safety-of-flight during routine air carrier flight operations and in response to aircraft system failures. These data are fundamental to and critical for the design and development of future increasingly autonomous systems that can better support the human in the cockpit. Eighteen U.S. airline crews flew various normal and non-normal procedures over a two-day period and their actions were recorded in response to failures. To quantify the human's contribution to safety of flight, crew complement was used as the experiment independent variable in a between-subjects design. Pilot actions and performance during single pilot and reduced crew operations were measured for comparison against the normal two-crew complement during normal and non-normal situations. This paper details the crew's actions, including decision-making, and responses while dealing with a drive shaft failure - one of 6 non-normal events that were simulated in this experiment.
Medication safety infrastructure in critical-access hospitals in Florida.
Winterstein, Almut G; Hartzema, Abraham G; Johns, Thomas E; De Leon, Jessica M; McDonald, Kathie; Henshaw, Zak; Pannell, Robert
2006-03-01
The medication safety infrastructure of critical-access hospitals (CAHs) in Florida was evaluated. Qualitative assessments, including a self-administered survey and site visits, were conducted in seven of nine CAHs between January and June 2003. The survey consisted of the Institute for Safe Medication Practices Medication Safety Self-assessment, the 2003 Joint Commission on Accreditation of Healthcare Organizations patient safety goals, health information technology (HIT) questions, and medication-use-process flow charts. On-site visits included interviews of CAH personnel who had safety responsibility and inspections of pharmacy facilities. The findings were compiled into a matrix reflecting structural and procedural components of the CAH medication safety infrastructure. The nine characteristics that emerged as targets for quality improvement (QI) were medication accessibility and storage, sterile product compounding, access to drug information, access to and utilization of patient information in medication order review, advanced safety technology, drug formularies and standardized medication protocols, safety culture, and medication reconciliation. Based on weighted importance and feasibility, QI efforts in CAHs should focus on enhancing medication order review systems, standardizing procedures for handling high-risk medications, promoting an appropriate safety culture, involvement in seamless care, and investment in HIT.
Verification and Validation of Flight-Critical Systems
NASA Technical Reports Server (NTRS)
Brat, Guillaume
2010-01-01
For the first time in many years, the NASA budget presented to congress calls for a focused effort on the verification and validation (V&V) of complex systems. This is mostly motivated by the results of the VVFCS (V&V of Flight-Critical Systems) study, which should materialize as a a concrete effort under the Aviation Safety program. This talk will present the results of the study, from requirements coming out of discussions with the FAA and the Joint Planning and Development Office (JPDO) to technical plan addressing the issue, and its proposed current and future V&V research agenda, which will be addressed by NASA Ames, Langley, and Dryden as well as external partners through NASA Research Announcements (NRA) calls. This agenda calls for pushing V&V earlier in the life cycle and take advantage of formal methods to increase safety and reduce cost of V&V. I will present the on-going research work (especially the four main technical areas: Safety Assurance, Distributed Systems, Authority and Autonomy, and Software-Intensive Systems), possible extensions, and how VVFCS plans on grounding the research in realistic examples, including an intended V&V test-bench based on an Integrated Modular Avionics (IMA) architecture and hosted by Dryden.
30 CFR 27.35 - Tests to determine life of critical components and subassemblies.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tests to determine life of critical components and subassemblies. 27.35 Section 27.35 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test...
30 CFR 27.35 - Tests to determine life of critical components and subassemblies.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Tests to determine life of critical components and subassemblies. 27.35 Section 27.35 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test...
9 CFR 417.6 - Inadequate HACCP Systems.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Inadequate HACCP Systems. 417.6 Section 417.6 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.6 Inadequate HACCP Systems. A HACCP system may be...
9 CFR 417.6 - Inadequate HACCP Systems.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Inadequate HACCP Systems. 417.6 Section 417.6 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.6 Inadequate HACCP Systems. A HACCP system may be...
9 CFR 417.6 - Inadequate HACCP Systems.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Inadequate HACCP Systems. 417.6 Section 417.6 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.6 Inadequate HACCP Systems. A HACCP system may be...
9 CFR 417.6 - Inadequate HACCP Systems.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Inadequate HACCP Systems. 417.6 Section 417.6 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.6 Inadequate HACCP Systems. A HACCP system may be...
9 CFR 417.6 - Inadequate HACCP Systems.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Inadequate HACCP Systems. 417.6 Section 417.6 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.6 Inadequate HACCP Systems. A HACCP system may be...
Sun, F; Chen, J; Tong, Q; Zeng, S
2007-01-01
Management of drinking water safety is changing towards an integrated risk assessment and risk management approach that includes all processes in a water supply system from catchment to consumers. However, given the large number of water supply systems in China and the cost of implementing such a risk assessment procedure, there is a necessity to first conduct a strategic screening analysis at a national level. An integrated methodology of risk assessment and screening analysis is thus proposed to evaluate drinking water safety of a conventional water supply system. The violation probability, indicating drinking water safety, is estimated at different locations of a water supply system in terms of permanganate index, ammonia nitrogen, turbidity, residual chlorine and trihalomethanes. Critical parameters with respect to drinking water safety are then identified, based on which an index system is developed to prioritize conventional water supply systems in implementing a detailed risk assessment procedure. The evaluation results are represented as graphic check matrices for the concerned hazards in drinking water, from which the vulnerability of a conventional water supply system is characterized.
Cyber Safety and Security for Reduced Crew Operations (RCO)
NASA Technical Reports Server (NTRS)
Driscoll, Kevin R.; Roy, Aloke; Ponchak, Denise S.; Downey, Alan N.
2017-01-01
NASA and the Aviation Industry is looking into reduced crew operations (RCO) that would cut today's required two-person flight crews down to a single pilot with support from ground-based crews. Shared responsibility across air and ground personnel will require highly reliable and secure data communication and supporting automation, which will be safety-critical for passenger and cargo aircraft. This paper looks at the different types and degrees of authority delegation given from the air to the ground and the ramifications of each, including the safety and security hazards introduced, the mitigation mechanisms for these hazards, and other demands on an RCO system architecture which would be highly invasive into (almost) all safety-critical avionics. The adjacent fields of unmanned aerial systems and autonomous ground vehicles are viewed to find problems that RCO may face and related aviation accident scenarios are described. The paper explores possible data communication architectures to meet stringent performance and information security (INFOSEC) requirements of RCO. Subsequently, potential challenges for RCO data communication authentication, encryption and non-repudiation are identified.
Donovan, Sarah-Louise; Salmon, Paul M; Lenné, Michael G; Horberry, Tim
2017-10-01
Safety leadership is an important factor in supporting safety in high-risk industries. This article contends that applying systems-thinking methods to examine safety leadership can support improved learning from incidents. A case study analysis was undertaken of a large-scale mining landslide incident in which no injuries or fatalities were incurred. A multi-method approach was adopted, in which the Critical Decision Method, Rasmussen's Risk Management Framework and Accimap method were applied to examine the safety leadership decisions and actions which enabled the safe outcome. The approach enabled Rasmussen's predictions regarding safety and performance to be examined in the safety leadership context, with findings demonstrating the distribution of safety leadership across leader and system levels, and the presence of vertical integration as key to supporting the successful safety outcome. In doing so, the findings also demonstrate the usefulness of applying systems-thinking methods to examine and learn from incidents in terms of what 'went right'. The implications, including future research directions, are discussed. Practitioner Summary: This paper presents a case study analysis, in which systems-thinking methods are applied to the examination of safety leadership decisions and actions during a large-scale mining landslide incident. The findings establish safety leadership as a systems phenomenon, and furthermore, demonstrate the usefulness of applying systems-thinking methods to learn from incidents in terms of what 'went right'. Implications, including future research directions, are discussed.
A Low-Cost, Effective, Fumes Exhaust System.
ERIC Educational Resources Information Center
Jacobs, C. O.
1979-01-01
Discusses the importance of avoiding welding fumes. The sources of these fumes are presented in a table. Criticizes currently used ventilation systems and reviews the Occupational Safety and Health Act requirements. Describes a low-cost exhaust system developed for agricultural mechanics laboratories. (LRA)
Risk-Based Probabilistic Approach to Aeropropulsion System Assessment
NASA Technical Reports Server (NTRS)
Tong, Michael T.
2002-01-01
In an era of shrinking development budgets and resources, where there is also an emphasis on reducing the product development cycle, the role of system assessment, performed in the early stages of an engine development program, becomes very critical to the successful development of new aeropropulsion systems. A reliable system assessment not only helps to identify the best propulsion system concept among several candidates, it can also identify which technologies are worth pursuing. This is particularly important for advanced aeropropulsion technology development programs, which require an enormous amount of resources. In the current practice of deterministic, or point-design, approaches, the uncertainties of design variables are either unaccounted for or accounted for by safety factors. This could often result in an assessment with unknown and unquantifiable reliability. Consequently, it would fail to provide additional insight into the risks associated with the new technologies, which are often needed by decision makers to determine the feasibility and return-on-investment of a new aircraft engine. In this work, an alternative approach based on the probabilistic method was described for a comprehensive assessment of an aeropropulsion system. The statistical approach quantifies the design uncertainties inherent in a new aeropropulsion system and their influences on engine performance. Because of this, it enhances the reliability of a system assessment. A technical assessment of a wave-rotor-enhanced gas turbine engine was performed to demonstrate the methodology. The assessment used probability distributions to account for the uncertainties that occur in component efficiencies and flows and in mechanical design variables. The approach taken in this effort was to integrate the thermodynamic cycle analysis embedded in the computer code NEPP (NASA Engine Performance Program) and the engine weight analysis embedded in the computer code WATE (Weight Analysis of Turbine Engines) with the fast probability integration technique (FPI). FPI was developed by Southwest Research Institute under contract with the NASA Glenn Research Center. The results were plotted in the form of cumulative distribution functions and sensitivity analyses and were compared with results from the traditional deterministic approach. The comparison showed that the probabilistic approach provides a more realistic and systematic way to assess an aeropropulsion system. The current work addressed the application of the probabilistic approach to assess specific fuel consumption, engine thrust, and weight. Similarly, the approach can be used to assess other aspects of aeropropulsion system performance, such as cost, acoustic noise, and emissions. Additional information is included in the original extended abstract.
14 CFR 417.309 - Flight safety system analysis.
Code of Federal Regulations, 2012 CFR
2012-01-01
... system anomaly occurring and all of its effects as determined by the single failure point analysis and... termination system. (c) Single failure point. A command control system must undergo an analysis that... fault tree analysis or a failure modes effects and criticality analysis; (2) Identify all possible...
14 CFR 417.309 - Flight safety system analysis.
Code of Federal Regulations, 2010 CFR
2010-01-01
... system anomaly occurring and all of its effects as determined by the single failure point analysis and... termination system. (c) Single failure point. A command control system must undergo an analysis that... fault tree analysis or a failure modes effects and criticality analysis; (2) Identify all possible...
14 CFR 417.309 - Flight safety system analysis.
Code of Federal Regulations, 2013 CFR
2013-01-01
... system anomaly occurring and all of its effects as determined by the single failure point analysis and... termination system. (c) Single failure point. A command control system must undergo an analysis that... fault tree analysis or a failure modes effects and criticality analysis; (2) Identify all possible...
14 CFR 417.309 - Flight safety system analysis.
Code of Federal Regulations, 2014 CFR
2014-01-01
... system anomaly occurring and all of its effects as determined by the single failure point analysis and... termination system. (c) Single failure point. A command control system must undergo an analysis that... fault tree analysis or a failure modes effects and criticality analysis; (2) Identify all possible...
14 CFR 417.309 - Flight safety system analysis.
Code of Federal Regulations, 2011 CFR
2011-01-01
... system anomaly occurring and all of its effects as determined by the single failure point analysis and... termination system. (c) Single failure point. A command control system must undergo an analysis that... fault tree analysis or a failure modes effects and criticality analysis; (2) Identify all possible...
ERIC Educational Resources Information Center
Revell, Lynn
2015-01-01
This article reviews the influence of liberal ideas on the capacity for Religious Education (RE) to consider religions critically in a climate of increasing government intervention in education. It finds that criticality in some areas of RE is absent or limited but that in key areas criticality is evident if not always deeply embedded. It…
Embedding Critical Thinking in IS Curricula
ERIC Educational Resources Information Center
Thomas, Theda; Davis, Tim; Kazlauskas, Alanah
2007-01-01
It is important for students to develop critical thinking and other higher-order thinking skills during their tertiary studies. Along with the ability to think critically comes the need to develop students' meta-cognitive skills. These abilities work together to enable students to control, monitor, and regulate their own cognitive processes and…
"Critical Bureaucracy" in Action: Embedding Student Voice into School Governance
ERIC Educational Resources Information Center
Carlile, Anna
2012-01-01
This article suggests a model for "youth voice" based on a participatory research methodology, "Illuminate". The article reports on research into the capacity for "Illuminate" to amount to "critical bureaucracy". Critical bureaucracy is presented as an approach to governance activities (here, in schools and further education colleges) which is…
NASA Astrophysics Data System (ADS)
Shamir, Adina; Zion, Michal; Spector Levi, Ornit
2008-08-01
The main objective of the study reported was to explore the effect on young children's critical thinking of a peer-tutoring training embedded with the metacognitive processes required for problem-based learning and, consequently, for critical thinking. The sample consisted of 90 first- and third-grade pupils (45 pairs) randomly assigned to the experimental or control group. The experimental tutors received the Peer Mediation training, an intervention containing embedded metacognitive processes. The control children received a general preparation for peer-assisted learning. Following their respective preparations, all the children participated in a peer-tutoring condition, videotaped for 25 min and subsequently analyzed with an adaptation of the Newman et al. (Interpers Comput Technol 3(2):56-77, 1995) content analysis instrument. Analysis of the discourse conducted during the tutoring session indicated that the tutors and tutees in the experimental groups exhibited greater depth of critical thinking, demonstrated in the higher Quality of Discourse Ratio calculated, than did the tutors and tutees in the control group. The findings supported previous results showing the efficacy of the Peer Mediation for Young Children mediation-training program, with its embedded metacognitive competencies, for reinforcing young children's higher-order thinking. Implications for educators are discussed.
A Model-based Framework for Risk Assessment in Human-Computer Controlled Systems
NASA Technical Reports Server (NTRS)
Hatanaka, Iwao
2000-01-01
The rapid growth of computer technology and innovation has played a significant role in the rise of computer automation of human tasks in modem production systems across all industries. Although the rationale for automation has been to eliminate "human error" or to relieve humans from manual repetitive tasks, various computer-related hazards and accidents have emerged as a direct result of increased system complexity attributed to computer automation. The risk assessment techniques utilized for electromechanical systems are not suitable for today's software-intensive systems or complex human-computer controlled systems. This thesis will propose a new systemic model-based framework for analyzing risk in safety-critical systems where both computers and humans are controlling safety-critical functions. A new systems accident model will be developed based upon modem systems theory and human cognitive processes to better characterize system accidents, the role of human operators, and the influence of software in its direct control of significant system functions. Better risk assessments will then be achievable through the application of this new framework to complex human-computer controlled systems.
Building Safer Systems With SpecTRM
NASA Technical Reports Server (NTRS)
2003-01-01
System safety, an integral component in software development, often poses a challenge to engineers designing computer-based systems. While the relaxed constraints on software design allow for increased power and flexibility, this flexibility introduces more possibilities for error. As a result, system engineers must identify the design constraints necessary to maintain safety and ensure that the system and software design enforces them. Safeware Engineering Corporation, of Seattle, Washington, provides the information, tools, and techniques to accomplish this task with its Specification Tools and Requirements Methodology (SpecTRM). NASA assisted in developing this engineering toolset by awarding the company several Small Business Innovation Research (SBIR) contracts with Ames Research Center and Langley Research Center. The technology benefits NASA through its applications for Space Station rendezvous and docking. SpecTRM aids system and software engineers in developing specifications for large, complex safety critical systems. The product enables engineers to find errors early in development so that they can be fixed with the lowest cost and impact on the system design. SpecTRM traces both the requirements and design rationale (including safety constraints) throughout the system design and documentation, allowing engineers to build required system properties into the design from the beginning, rather than emphasizing assessment at the end of the development process when changes are limited and costly.System safety, an integral component in software development, often poses a challenge to engineers designing computer-based systems. While the relaxed constraints on software design allow for increased power and flexibility, this flexibility introduces more possibilities for error. As a result, system engineers must identify the design constraints necessary to maintain safety and ensure that the system and software design enforces them. Safeware Engineering Corporation, of Seattle, Washington, provides the information, tools, and techniques to accomplish this task with its Specification Tools and Requirements Methodology (SpecTRM). NASA assisted in developing this engineering toolset by awarding the company several Small Business Innovation Research (SBIR) contracts with Ames Research Center and Langley Research Center. The technology benefits NASA through its applications for Space Station rendezvous and docking. SpecTRM aids system and software engineers in developing specifications for large, complex safety critical systems. The product enables engineers to find errors early in development so that they can be fixed with the lowest cost and impact on the system design. SpecTRM traces both the requirements and design rationale (including safety constraints) throughout the system design and documentation, allowing engineers to build required system properties into the design from the beginning, rather than emphasizing assessment at the end of the development process when changes are limited and costly.
Comprehensive target populations for current active safety systems using national crash databases.
Kusano, Kristofer D; Gabler, Hampton C
2014-01-01
The objective of active safety systems is to prevent or mitigate collisions. A critical component in the design of active safety systems is the identification of the target population for a proposed system. The target population for an active safety system is that set of crashes that a proposed system could prevent or mitigate. Target crashes have scenarios in which the sensors and algorithms would likely activate. For example, the rear-end crash scenario, where the front of one vehicle contacts another vehicle traveling in the same direction and in the same lane as the striking vehicle, is one scenario for which forward collision warning (FCW) would be most effective in mitigating or preventing. This article presents a novel set of precrash scenarios based on coded variables from NHTSA's nationally representative crash databases in the United States. Using 4 databases (National Automotive Sampling System-General Estimates System [NASS-GES], NASS Crashworthiness Data System [NASS-CDS], Fatality Analysis Reporting System [FARS], and National Motor Vehicle Crash Causation Survey [NMVCCS]) the scenarios developed in this study can be used to quantify the number of police-reported crashes, seriously injured occupants, and fatalities that are applicable to proposed active safety systems. In this article, we use the precrash scenarios to identify the target populations for FCW, pedestrian crash avoidance systems (PCAS), lane departure warning (LDW), and vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) systems. Crash scenarios were derived using precrash variables (critical event, accident type, precrash movement) present in all 4 data sources. This study found that these active safety systems could potentially mitigate approximately 1 in 5 of all severity and serious injury crashes in the United States and 26 percent of fatal crashes. Annually, this corresponds to 1.2 million all severity, 14,353 serious injury (MAIS 3+), and 7412 fatal crashes. In addition, we provide the source code for the crash scenarios as an appendix (see online supplement) to this article so that researchers can use the crash scenarios in future research.
Terahertz computed tomography of NASA thermal protection system materials
NASA Astrophysics Data System (ADS)
Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.
2012-05-01
A terahertz (THz) axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 m3 (1 ft3) with no safety concerns as for x-ray computed tomography. In this study, the THz-CT system was evaluated for its ability to detect and characterize 1) an embedded void in Space Shuttle external fuel tank thermal protection system (TPS) foam material and 2) impact damage in a TPS configuration under consideration for use in NASA's multi-purpose Orion crew module (CM). Micro-focus X-ray CT is utilized to characterize the flaws and provide a baseline for which to compare the THz CT results.
Robust optical sensors for safety critical automotive applications
NASA Astrophysics Data System (ADS)
De Locht, Cliff; De Knibber, Sven; Maddalena, Sam
2008-02-01
Optical sensors for the automotive industry need to be robust, high performing and low cost. This paper focuses on the impact of automotive requirements on optical sensor design and packaging. Main strategies to lower optical sensor entry barriers in the automotive market include: Perform sensor calibration and tuning by the sensor manufacturer, sensor test modes on chip to guarantee functional integrity at operation, and package technology is key. As a conclusion, optical sensor applications are growing in automotive. Optical sensor robustness matured to the level of safety critical applications like Electrical Power Assisted Steering (EPAS) and Drive-by-Wire by optical linear arrays based systems and Automated Cruise Control (ACC), Lane Change Assist and Driver Classification/Smart Airbag Deployment by camera imagers based systems.
Applications of a damage tolerance analysis methodology in aircraft design and production
NASA Technical Reports Server (NTRS)
Woodward, M. R.; Owens, S. D.; Law, G. E.; Mignery, L. A.
1992-01-01
Objectives of customer mandated aircraft structural integrity initiatives in design are to guide material selection, to incorporate fracture resistant concepts in the design, to utilize damage tolerance based allowables and planned inspection procedures necessary to enhance the safety and reliability of manned flight vehicles. However, validated fracture analysis tools for composite structures are needed to accomplish these objectives in a timely and economical manner. This paper briefly describes the development, validation, and application of a damage tolerance methodology for composite airframe structures. A closed-form analysis code, entitled SUBLAM was developed to predict the critical biaxial strain state necessary to cause sublaminate buckling-induced delamination extension in an impact damaged composite laminate. An embedded elliptical delamination separating a thin sublaminate from a thick parent laminate is modelled. Predicted failure strains were correlated against a variety of experimental data that included results from compression after impact coupon and element tests. An integrated analysis package was developed to predict damage tolerance based margin-of-safety (MS) using NASTRAN generated loads and element information. Damage tolerance aspects of new concepts are quickly and cost-effectively determined without the need for excessive testing.
The Critical Mass Laboratory at Rocky Flats
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rothe, Robert E
2003-10-15
The Critical Mass Laboratory (CML) at Rocky Flats northwest of Denver, Colorado, was built in 1964 and commissioned to conduct nuclear experiments on January 28, 1965. It was built to attain more accurate and precise experimental data to ensure nuclear criticality safety at the plant than were previously possible. Prior to its construction, safety data were obtained from long extrapolations of subcritical data (called in situ experiments), calculated parameters from reactor engineering 'models', and a few other imprecise methods. About 1700 critical and critical-approach experiments involving several chemical forms of enriched uranium and plutonium were performed between then and 1988.more » These experiments included single units and arrays of fissile materials, reflected and 'bare' systems, and configurations with various degrees of moderation, as well as some containing strong neutron absorbers. In 1989, a raid by the Federal Bureau of Investigation (FBI) caused the plant as a whole to focus on 'resumption' instead of further criticality safety experiments. Though either not recognized or not admitted for a few years, that FBI raid did sound the death knell for the CML. The plant's optimistic goal of resumption evolved to one of deactivation, decommissioning, and plantwide demolition during the 1990s. The once-proud CML facility was finally demolished in April of 2002.« less
NASA Technical Reports Server (NTRS)
Mcdonald, K. D.; Miller, C. M.; Scales, W. C.; Dement, D. K.
1990-01-01
The projected application and requirements in the near term (to 1995) and far term (to 2010) for aeronautical mobile services supporting air traffic control operations are addressed. The implications of these requirements on spectrum needs, and the resulting effects on the satellite design and operation are discussed. The U.S. is working with international standards and regulatory organizations to develop the necessary aviation standards, signalling protocols, and implementation methods. In the provision of aeronautical safety services, a number of critical issues were identified, including system reliability and availability, access time, channel restoration time, interoperability, pre-emption techniques, and the system network interfaces. Means for accomplishing these critical services in the aeronautical mobile satellite service (AMSS), and the various activities relating to the future provision of aeronautical safety services are addressed.
NASA Astrophysics Data System (ADS)
McDonald, K. D.; Miller, C. M.; Scales, W. C.; Dement, D. K.
The projected application and requirements in the near term (to 1995) and far term (to 2010) for aeronautical mobile services supporting air traffic control operations are addressed. The implications of these requirements on spectrum needs, and the resulting effects on the satellite design and operation are discussed. The U.S. is working with international standards and regulatory organizations to develop the necessary aviation standards, signalling protocols, and implementation methods. In the provision of aeronautical safety services, a number of critical issues were identified, including system reliability and availability, access time, channel restoration time, interoperability, pre-emption techniques, and the system network interfaces. Means for accomplishing these critical services in the aeronautical mobile satellite service (AMSS), and the various activities relating to the future provision of aeronautical safety services are addressed.
Impact of nuclear data uncertainty on safety calculations for spent nuclear fuel geological disposal
NASA Astrophysics Data System (ADS)
Herrero, J. J.; Rochman, D.; Leray, O.; Vasiliev, A.; Pecchia, M.; Ferroukhi, H.; Caruso, S.
2017-09-01
In the design of a spent nuclear fuel disposal system, one necessary condition is to show that the configuration remains subcritical at time of emplacement but also during long periods covering up to 1,000,000 years. In the context of criticality safety applying burn-up credit, k-eff eigenvalue calculations are affected by nuclear data uncertainty mainly in the burnup calculations simulating reactor operation and in the criticality calculation for the disposal canister loaded with the spent fuel assemblies. The impact of nuclear data uncertainty should be included in the k-eff value estimation to enforce safety. Estimations of the uncertainty in the discharge compositions from the CASMO5 burn-up calculation phase are employed in the final MCNP6 criticality computations for the intact canister configuration; in between, SERPENT2 is employed to get the spent fuel composition along the decay periods. In this paper, nuclear data uncertainty was propagated by Monte Carlo sampling in the burn-up, decay and criticality calculation phases and representative values for fuel operated in a Swiss PWR plant will be presented as an estimation of its impact.
Fuel level sensor based on polymer optical fiber Bragg gratings for aircraft applications
NASA Astrophysics Data System (ADS)
Marques, C. A. F.; Pospori, A.; Sáez-Rodríguez, D.; Nielsen, K.; Bang, O.; Webb, D. J.
2016-04-01
Safety in civil aviation is increasingly important due to the increase in flight routes and their more challenging nature. Like other important systems in aircraft, fuel level monitoring is always a technical challenge. The most frequently used level sensors in aircraft fuel systems are based on capacitive, ultrasonic and electric techniques, however they suffer from intrinsic safety concerns in explosive environments combined with issues relating to reliability and maintainability. In the last few years, optical fiber liquid level sensors (OFLLSs) have been reported to be safe and reliable and present many advantages for aircraft fuel measurement. Different OFLLSs have been developed, such as the pressure type, float type, optical radar type, TIR type and side-leaking type. Amongst these, many types of OFLLSs based on fiber gratings have been demonstrated. However, these sensors have not been commercialized because they exhibit some drawbacks: low sensitivity, limited range, long-term instability, or limited resolution. In addition, any sensors that involve direct interaction of the optical field with the fuel (either by launching light into the fuel tank or via the evanescent field of a fiber-guided mode) must be able to cope with the potential build up of contamination - often bacterial - on the optical surface. In this paper, a fuel level sensor based on microstructured polymer optical fiber Bragg gratings (mPOFBGs), including poly (methyl methacrylate) (PMMA) and TOPAS fibers, embedded in diaphragms is investigated in detail. The mPOFBGs are embedded in two different types of diaphragms and their performance is investigated with aviation fuel for the first time, in contrast to our previous works, where water was used. Our new system exhibits a high performance when compared with other previously published in the literature, making it a potentially useful tool for aircraft fuel monitoring.
A Solution on Identification and Rearing Files Insmallhold Pig Farming
NASA Astrophysics Data System (ADS)
Xiong, Benhai; Fu, Runting; Lin, Zhaohui; Luo, Qingyao; Yang, Liang
In order to meet government supervision of pork production safety as well as consumeŕs right to know what they buy, this study adopts animal identification, mobile PDA reader, GPRS and other information technologies, and put forward a data collection method to set up rearing files of pig in smallhold pig farming, and designs related metadata structures and its mobile database, and develops a mobile PDA embedded system to collect individual information of pig and uploading into the remote central database, and finally realizes mobile links to the a specific website. The embedded PDA can identify both a special pig bar ear tag appointed by the Ministry of Agricultural and a general data matrix bar ear tag designed by this study by mobile reader, and can record all kinds of inputs data including bacterins, feed additives, animal drugs and even some forbidden medicines and submitted them to the center database through GPRS. At the same time, the remote center database can be maintained by mobile PDA and GPRS, and finally reached pork tracking from its origin to consumption and its tracing through turn-over direction. This study has suggested a feasible technology solution how to set up network pig electronic rearing files involved smallhold pig farming based on farmer and the solution is proved practical through its application in the Tianjińs pork quality traceability system construction. Although some individual techniques have some adverse effects on the system running such as GPRS transmitting speed now, these will be resolved with the development of communication technology. The full implementation of the solution around China will supply technical supports in guaranteeing the quality and safety of pork production supervision and meet consumer demand.
NASA Technical Reports Server (NTRS)
Figueroa, Fernando; Morris, Jon; Turowski, Mark; Franzl, Richard; Walker, Mark; Kapadia, Ravi; Venkatesh, Meera; Schmalzel, John
2010-01-01
Severe weather events are likely occurrences on the Mississippi Gulf Coast. It is important to rapidly diagnose and mitigate the effects of storms on Stennis Space Center's rocket engine test complex to avoid delays to critical test article programs, reduce costs, and maintain safety. An Integrated Systems Health Management (ISHM) approach and technologies are employed to integrate environmental (weather) monitoring, structural modeling, and the suite of available facility instrumentation to provide information for readiness before storms, rapid initial damage assessment to guide mitigation planning, and then support on-going assurance as repairs are effected and finally support recertification. The system is denominated Katrina Storm Monitoring System (KStorMS). Integrated Systems Health Management (ISHM) describes a comprehensive set of capabilities that provide insight into the behavior the health of a system. Knowing the status of a system allows decision makers to effectively plan and execute their mission. For example, early insight into component degradation and impending failures provides more time to develop work around strategies and more effectively plan for maintenance. Failures of system elements generally occur over time. Information extracted from sensor data, combined with system-wide knowledge bases and methods for information extraction and fusion, inference, and decision making, can be used to detect incipient failures. If failures do occur, it is critical to detect and isolate them, and suggest an appropriate course of action. ISHM enables determining the condition (health) of every element in a complex system-of-systems or SoS (detect anomalies, diagnose causes, predict future anomalies), and provide data, information, and knowledge (DIaK) to control systems for safe and effective operation. ISHM capability is achieved by using a wide range of technologies that enable anomaly detection, diagnostics, prognostics, and advise for control: (1) anomaly detection algorithms and strategies, (2) fusion of DIaK for anomaly detection (model-based, numerical, statistical, empirical, expert-based, qualitative, etc.), (3) diagnostics/prognostics strategies and methods, (4) user interface, (5) advanced control strategies, (6) integration architectures/frameworks, (7) embedding of intelligence. Many of these technologies are mature, and they are being used in the KStorMS. The paper will describe the design, implementation, and operation of the KStorMS; and discuss further evolution to support other needs such as condition-based maintenance (CBM).
The Shale Hills Critical Zone Observatory for Embedded Sensing and Simulation
NASA Astrophysics Data System (ADS)
Duffy, C.; Davis, K.; Kane, T.; Boyer, E.
2009-04-01
The future of environmental observing systems will utilize embedded sensor networks with continuous real-time measurement of hydrologic, atmospheric, biogeochemical, and ecological variables across diverse terrestrial environments. Embedded environmental sensors, benefitting from advances in information sciences, networking technology, materials science, computing capacity, and data synthesis methods, are undergoing revolutionary change. It is now possible to field spatially-distributed, multi-node sensor networks that provide density and spatial coverage previously accessible only via numerical simulation. At the same time, computational tools are advancing rapidly to the point where it is now possible to simulate the physical processes controlling individual parcels of water and solutes through the complete terrestrial water cycle. Our goal for the Penn State Critical Zone Observatory is to apply environmental sensor arrays, integrated hydrologic models deployed and coordinated at a testbed within the Penn State Experimental Forest. The NSF-funded CZO is designed to observe the detailed space and time complexities of the water and energy cycle for a watershed and ultimately the river basin for all physical states and fluxes (groundwater, soil moisture, temperature, streamflow, latent heat, snowmelt, chemistry, isotopes etc.). Presently fully-coupled physical models are being developed that link the atmosphere-land-vegetation-subsurface system into a fully-coupled distributed system. During the last 5 years the Penn State Integrated Hydrologic Modeling System has been under development as an open-source community modeling project funded by NSF EAR/GEO and NSF CBET/ENG. PIHM represents a strategy for the formulation and solution of fully-coupled process equations at the watershed and river basin scales, and includes a tightly coupled GIS tool for data handling, domain decomposition, optimal unstructured grid generation, and model parameterization. (PIHM; http://sourceforge.net/projects/pihmmodel/; http://sourceforge.net/projects/pihmgis/ ) The CZO sensor and simulation system is being developed to have the following elements: 1) extensive, spatially-distributed smart sensor networks to gather intensive soil, geologic, hydrologic, geochemical and isotopic data; 2) spatially-explicit multiphysics models/solutions of the land-subsurface-vegetation-atmosphere system; and 3) parallel/distributed, adaptive algorithms for rapidly simulating the states of the watershed at high resolution, and 4) signal processing tools for data mining and parameter estimation. The prototype proposed sensor array and simulation system proposed is demonstrated with preliminary results from our first year.
Jiaxi, Qiang; Lin, Yang; Jianhui, He; Qisheng, Zhou
2013-01-01
Batteries, as the main or assistant power source of EV (Electric Vehicle), are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS), the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application. PMID:24194677
Jiaxi, Qiang; Lin, Yang; Jianhui, He; Qisheng, Zhou
2013-01-01
Batteries, as the main or assistant power source of EV (Electric Vehicle), are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS), the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application.
14 CFR 415.109 - Launch description.
Code of Federal Regulations, 2012 CFR
2012-01-01
...) Identification of any facilities at the launch site that will be used for launch processing and flight. (b... dimensions and weight; (iii) Location of all safety critical systems, including any flight termination hardware, tracking aids, or telemetry systems; (iv) Location of all major launch vehicle control systems...
14 CFR 415.109 - Launch description.
Code of Federal Regulations, 2013 CFR
2013-01-01
...) Identification of any facilities at the launch site that will be used for launch processing and flight. (b... dimensions and weight; (iii) Location of all safety critical systems, including any flight termination hardware, tracking aids, or telemetry systems; (iv) Location of all major launch vehicle control systems...
14 CFR 415.109 - Launch description.
Code of Federal Regulations, 2014 CFR
2014-01-01
...) Identification of any facilities at the launch site that will be used for launch processing and flight. (b... dimensions and weight; (iii) Location of all safety critical systems, including any flight termination hardware, tracking aids, or telemetry systems; (iv) Location of all major launch vehicle control systems...
Multiview Locally Linear Embedding for Effective Medical Image Retrieval
Shen, Hualei; Tao, Dacheng; Ma, Dianfu
2013-01-01
Content-based medical image retrieval continues to gain attention for its potential to assist radiological image interpretation and decision making. Many approaches have been proposed to improve the performance of medical image retrieval system, among which visual features such as SIFT, LBP, and intensity histogram play a critical role. Typically, these features are concatenated into a long vector to represent medical images, and thus traditional dimension reduction techniques such as locally linear embedding (LLE), principal component analysis (PCA), or laplacian eigenmaps (LE) can be employed to reduce the “curse of dimensionality”. Though these approaches show promising performance for medical image retrieval, the feature-concatenating method ignores the fact that different features have distinct physical meanings. In this paper, we propose a new method called multiview locally linear embedding (MLLE) for medical image retrieval. Following the patch alignment framework, MLLE preserves the geometric structure of the local patch in each feature space according to the LLE criterion. To explore complementary properties among a range of features, MLLE assigns different weights to local patches from different feature spaces. Finally, MLLE employs global coordinate alignment and alternating optimization techniques to learn a smooth low-dimensional embedding from different features. To justify the effectiveness of MLLE for medical image retrieval, we compare it with conventional spectral embedding methods. We conduct experiments on a subset of the IRMA medical image data set. Evaluation results show that MLLE outperforms state-of-the-art dimension reduction methods. PMID:24349277
A systems-based food safety evaluation: an experimental approach.
Higgins, Charles L; Hartfield, Barry S
2004-11-01
Food establishments are complex systems with inputs, subsystems, underlying forces that affect the system, outputs, and feedback. Building on past exploration of the hazard analysis critical control point concept and Ludwig von Bertalanffy General Systems Theory, the National Park Service (NPS) is attempting to translate these ideas into a realistic field assessment of food service establishments and to use information gathered by these methods in efforts to improve food safety. Over the course of the last two years, an experimental systems-based methodology has been drafted, developed, and tested by the NPS Public Health Program. This methodology is described in this paper.
Monte Carlo capabilities of the SCALE code system
Rearden, Bradley T.; Petrie, Jr., Lester M.; Peplow, Douglas E.; ...
2014-09-12
SCALE is a broadly used suite of tools for nuclear systems modeling and simulation that provides comprehensive, verified and validated, user-friendly capabilities for criticality safety, reactor physics, radiation shielding, and sensitivity and uncertainty analysis. For more than 30 years, regulators, licensees, and research institutions around the world have used SCALE for nuclear safety analysis and design. SCALE provides a “plug-and-play” framework that includes three deterministic and three Monte Carlo radiation transport solvers that can be selected based on the desired solution, including hybrid deterministic/Monte Carlo simulations. SCALE includes the latest nuclear data libraries for continuous-energy and multigroup radiation transport asmore » well as activation, depletion, and decay calculations. SCALE’s graphical user interfaces assist with accurate system modeling, visualization, and convenient access to desired results. SCALE 6.2 will provide several new capabilities and significant improvements in many existing features, especially with expanded continuous-energy Monte Carlo capabilities for criticality safety, shielding, depletion, and sensitivity and uncertainty analysis. Finally, an overview of the Monte Carlo capabilities of SCALE is provided here, with emphasis on new features for SCALE 6.2.« less
DOT National Transportation Integrated Search
2008-03-01
Climate affects the design, construction, safety, operations, and maintenance of transportation : infrastructure and systems. The prospect of a changing climate raises critical questions : regarding how alterations in temperature, precipitation, stor...
49 CFR 238.425 - Electrical system.
Code of Federal Regulations, 2013 CFR
2013-10-01
... insulated from the supports that hold them. (d) Electromagnetic interference and compatibility. (1) The operating railroad shall ensure electromagnetic compatibility of the safety-critical equipment systems with their environment. Electromagnetic compatibility can be achieved through equipment design or changes to...
49 CFR 238.425 - Electrical system.
Code of Federal Regulations, 2010 CFR
2010-10-01
... insulated from the supports that hold them. (d) Electromagnetic interference and compatibility. (1) The operating railroad shall ensure electromagnetic compatibility of the safety-critical equipment systems with their environment. Electromagnetic compatibility can be achieved through equipment design or changes to...
49 CFR 238.425 - Electrical system.
Code of Federal Regulations, 2012 CFR
2012-10-01
... insulated from the supports that hold them. (d) Electromagnetic interference and compatibility. (1) The operating railroad shall ensure electromagnetic compatibility of the safety-critical equipment systems with their environment. Electromagnetic compatibility can be achieved through equipment design or changes to...