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Sample records for achieve reliable information

  1. Reliability and Validity of Information about Student Achievement: Comparing Large-Scale and Classroom Testing Contexts

    ERIC Educational Resources Information Center

    Cizek, Gregory J.

    2009-01-01

    Reliability and validity are two characteristics that must be considered whenever information about student achievement is collected. However, those characteristics--and the methods for evaluating them--differ in large-scale testing and classroom testing contexts. This article presents the distinctions between reliability and validity in the two…

  2. Achieving reliable communication in dynamic emergency responses.

    PubMed

    Chipara, Octav; Plymoth, Anders N; Liu, Fang; Huang, Ricky; Evans, Brian; Johansson, Per; Rao, Ramesh; Griswold, William G

    2011-01-01

    Emergency responses require the coordination of first responders to assess the condition of victims, stabilize their condition, and transport them to hospitals based on the severity of their injuries. WIISARD is a system designed to facilitate the collection of medical information and its reliable dissemination during emergency responses. A key challenge in WIISARD is to deliver data with high reliability as first responders move and operate in a dynamic radio environment fraught with frequent network disconnections. The initial WIISARD system employed a client-server architecture and an ad-hoc routing protocol was used to exchange data. The system had low reliability when deployed during emergency drills. In this paper, we identify the underlying causes of unreliability and propose a novel peer-to-peer architecture that in combination with a gossip-based communication protocol achieves high reliability. Empirical studies show that compared to the initial WIISARD system, the redesigned system improves reliability by as much as 37% while reducing the number of transmitted packets by 23%. PMID:22195075

  3. Achieving Reliable Communication in Dynamic Emergency Responses

    PubMed Central

    Chipara, Octav; Plymoth, Anders N.; Liu, Fang; Huang, Ricky; Evans, Brian; Johansson, Per; Rao, Ramesh; Griswold, William G.

    2011-01-01

    Emergency responses require the coordination of first responders to assess the condition of victims, stabilize their condition, and transport them to hospitals based on the severity of their injuries. WIISARD is a system designed to facilitate the collection of medical information and its reliable dissemination during emergency responses. A key challenge in WIISARD is to deliver data with high reliability as first responders move and operate in a dynamic radio environment fraught with frequent network disconnections. The initial WIISARD system employed a client-server architecture and an ad-hoc routing protocol was used to exchange data. The system had low reliability when deployed during emergency drills. In this paper, we identify the underlying causes of unreliability and propose a novel peer-to-peer architecture that in combination with a gossip-based communication protocol achieves high reliability. Empirical studies show that compared to the initial WIISARD system, the redesigned system improves reliability by as much as 37% while reducing the number of transmitted packets by 23%. PMID:22195075

  4. Reliability achievement in high technology space systems

    NASA Technical Reports Server (NTRS)

    Lindstrom, D. L.

    1981-01-01

    The production of failure-free hardware is discussed. The elements required to achieve such hardware are: technical expertise to design, analyze, and fully understand the design; use of high reliability parts and materials control in the manufacturing process; and testing to understand the system and weed out defects. The durability of the Hughes family of satellites is highlighted.

  5. Understanding the Elements of Operational Reliability: A Key for Achieving High Reliability

    NASA Technical Reports Server (NTRS)

    Safie, Fayssal M.

    2010-01-01

    This viewgraph presentation reviews operational reliability and its role in achieving high reliability through design and process reliability. The topics include: 1) Reliability Engineering Major Areas and interfaces; 2) Design Reliability; 3) Process Reliability; and 4) Reliability Applications.

  6. Reliability Technology to Achieve Insertion of Advanced Packaging (RELTECH) program

    NASA Technical Reports Server (NTRS)

    Fayette, Daniel F.; Speicher, Patricia; Stoklosa, Mark J.; Evans, Jillian V.; Evans, John W.; Gentile, Mike; Pagel, Chuck A.; Hakim, Edward

    1993-01-01

    A joint military-commercial effort to evaluate multichip module (MCM) structures is discussed. The program, Reliability Technology to Achieve Insertion of Advanced Packaging (RELTECH), has been designed to identify the failure mechanisms that are possible in MCM structures. The RELTECH test vehicles, technical assessment task, product evaluation plan, reliability modeling task, accelerated and environmental testing, and post-test physical analysis and failure analysis are described. The information obtained through RELTECH can be used to address standardization issues, through development of cost effective qualification and appropriate screening criteria, for inclusion into a commercial specification and the MIL-H-38534 general specification for hybrid microcircuits.

  7. Methods and Costs to Achieve Ultra Reliable Life Support

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.

    2012-01-01

    A published Mars mission is used to explore the methods and costs to achieve ultra reliable life support. The Mars mission and its recycling life support design are described. The life support systems were made triply redundant, implying that each individual system will have fairly good reliability. Ultra reliable life support is needed for Mars and other long, distant missions. Current systems apparently have insufficient reliability. The life cycle cost of the Mars life support system is estimated. Reliability can be increased by improving the intrinsic system reliability, adding spare parts, or by providing technically diverse redundant systems. The costs of these approaches are estimated. Adding spares is least costly but may be defeated by common cause failures. Using two technically diverse systems is effective but doubles the life cycle cost. Achieving ultra reliability is worth its high cost because the penalty for failure is very high.

  8. Recent achievements in module reliability research. [amorphous Si solar cells

    NASA Technical Reports Server (NTRS)

    Ross, R. G., Jr.

    1987-01-01

    After 10 years of extensive research on crystalline-silicon flat-plate photovoltaic modules, the emphasis of recent reliability research has shifted to the emerging first-generation thin-film amorphous-silicon modules. These modules share much in common with their crystalline precursors, but also include many materials and processes that demand the development of reliability technologies. Key research thrusts include light-induced effects, cell corrosion, thermal diffusion, hot-spot heating, and electrical isolation of the cells from the module exterior. Research goals and recent achievements are described in each of these areas.

  9. Infants track the reliability of potential informants.

    PubMed

    Tummeltshammer, Kristen Swan; Wu, Rachel; Sobel, David M; Kirkham, Natasha Z

    2014-09-01

    Across two eye-tracking experiments, we showed that infants are sensitive to the statistical reliability of informative cues and selective in their use of information generated by such cues. We familiarized 8-month-olds with faces (Experiment 1) or arrows (Experiment 2) that cued the locations of animated animals with different degrees of reliability. The reliable cue always cued a box containing an animation, whereas the unreliable cue cued a box that contained an animation only 25% of the time. At test, infants searched longer in the boxes that were reliably cued, but did not search longer in the boxes that were unreliably cued. At generalization, when boxes were cued that never contained animations before, only infants in the face experiment followed the reliable cue. These results provide the first evidence that even young infants can track the reliability of potential informants and use this information judiciously to modify their future behavior. PMID:25022277

  10. Finding Reliable Health Information Online

    MedlinePlus

    ... with your physician any articles that interest you. Internet Credibility Help from Genetic Alliance The Access To ... for people developing educational materials. Top of page Internet Resources Genetics Information Genetic Testing Registry www.ncbi. ...

  11. Desert ants achieve reliable recruitment across noisy interactions

    PubMed Central

    Razin, Nitzan; Eckmann, Jean-Pierre; Feinerman, Ofer

    2013-01-01

    We study how desert ants, Cataglyphis niger, a species that lacks pheromone-based recruitment mechanisms, inform each other about the presence of food. Our results are based on automated tracking that allows us to collect a large database of ant trajectories and interactions. We find that interactions affect an ant's speed within the nest. Fast ants tend to slow down, whereas slow ones increase their speed when encountering a faster ant. Faster ants tend to exit the nest more frequently than slower ones. So, if an ant gains enough speed through encounters with others, then she tends to leave the nest and look for food. On the other hand, we find that the probability for her to leave the nest depends only on her speed, but not on whether she had recently interacted with a recruiter that has found the food. This suggests a recruitment system in which ants communicate their state by very simple interactions. Based on this assumption, we estimate the information-theoretical channel capacity of the ants’ pairwise interactions. We find that the response to the speed of an interacting nest-mate is very noisy. The question is then how random interactions with ants within the nest can be distinguished from those interactions with a recruiter who has found food. Our measurements and model suggest that this distinction does not depend on reliable communication but on behavioural differences between ants that have found the food and those that have not. Recruiters retain high speeds throughout the experiment, regardless of the ants they interact with; non-recruiters communicate with a limited number of nest-mates and adjust their speed following these interactions. These simple rules lead to the formation of a bistable switch on the level of the group that allows the distinction between recruitment and random noise in the nest. A consequence of the mechanism we propose is a negative effect of ant density on exit rates and recruitment success. This is, indeed, confirmed by

  12. Achieving High Reliability Operations Through Multi-Program Integration

    SciTech Connect

    Holly M. Ashley; Ronald K. Farris; Robert E. Richards

    2009-04-01

    Over the last 20 years the Idaho National Laboratory (INL) has adopted a number of operations and safety-related programs which has each periodically taken its turn in the limelight. As new programs have come along there has been natural competition for resources, focus and commitment. In the last few years, the INL has made real progress in integrating all these programs and are starting to realize important synergies. Contributing to this integration are both collaborative individuals and an emerging shared vision and goal of the INL fully maturing in its high reliability operations. This goal is so powerful because the concept of high reliability operations (and the resulting organizations) is a masterful amalgam and orchestrator of the best of all the participating programs (i.e. conduct of operations, behavior based safety, human performance, voluntary protection, quality assurance, and integrated safety management). This paper is a brief recounting of the lessons learned, thus far, at the INL in bringing previously competing programs into harmony under the goal (umbrella) of seeking to perform regularly as a high reliability organization. In addition to a brief diagram-illustrated historical review, the authors will share the INL’s primary successes (things already effectively stopped or started) and the gaps yet to be bridged.

  13. Reliability of dynamic systems under limited information.

    SciTech Connect

    Field, Richard V., Jr.; Grigoriu, Mircea

    2006-09-01

    A method is developed for reliability analysis of dynamic systems under limited information. The available information includes one or more samples of the system output; any known information on features of the output can be used if available. The method is based on the theory of non-Gaussian translation processes and is shown to be particularly suitable for problems of practical interest. For illustration, we apply the proposed method to a series of simple example problems and compare with results given by traditional statistical estimators in order to establish the accuracy of the method. It is demonstrated that the method delivers accurate results for the case of linear and nonlinear dynamic systems, and can be applied to analyze experimental data and/or mathematical model outputs. Two complex applications of direct interest to Sandia are also considered. First, we apply the proposed method to assess design reliability of a MEMS inertial switch. Second, we consider re-entry body (RB) component vibration response during normal re-entry, where the objective is to estimate the time-dependent probability of component failure. This last application is directly relevant to re-entry random vibration analysis at Sandia, and may provide insights on test-based and/or model-based qualification of weapon components for random vibration environments.

  14. Validity and Reliability of Trichotomous Achievement Goal Scale

    ERIC Educational Resources Information Center

    Ilker, Gokce Erturan; Arslan, Yunus; Demirhan, Giyasettin

    2011-01-01

    The Trichotomous Achievement Goal Scale was developed by Agbuga and Xiang (2008) by including selected items from the scales of Duda and Nicholls (1992), Elliot (1999), and Elliot and Church (1997) and adapting them into Turkish. The scale consists of 18 items, and students rated each item on a 7-point Likert scale. To ascertain the validity and…

  15. Development of Achievement Test: Validity and Reliability Study for Achievement Test on Matter Changing

    ERIC Educational Resources Information Center

    Kara, Filiz; Celikler, Dilek

    2015-01-01

    For "Matter Changing" unit included in the Secondary School 5th Grade Science Program, it is intended to develop a test conforming the gains described in the program, and that can determine students' achievements. For this purpose, a multiple-choice test of 48 questions is arranged, consisting of 8 questions for each gain included in the…

  16. Improving Reliability and Validity of "Achievement via Conformance" Through Computer Applications.

    ERIC Educational Resources Information Center

    Riggs, Donald E.

    This paper describes an experiment conducted in order to improve the reliability and validity of the Achievement via Conformance (AC) scale of the California Psychological Inventory (CPI). The primary goal of AC is to identify those factors of interest and motivation which facilitate achievement in any setting where conformance is positive…

  17. Evaluating reliability and resolution of ensemble forecasts using information theory

    NASA Astrophysics Data System (ADS)

    Weijs, Steven; van de Giesen, Nick

    2010-05-01

    -theoretical measures of entropy (uncertainty) and relative entropy (Kullback-Leibler divergence) to formulate scores analogous to the BS and RPS, that allow for a similar decomposition into uncertainty, resolution and reliability. The BS and it's components are shown to be second order approximations their information-theoretical counterparts. In the new score, named the divergence score, the resolution can be seen as the information gained from the conditioning data on which the forecast is based, while the reliability measures to which degree the information gain is annihilated by the information loss that occurs due to inadequate processing of this data. In other words, resolution measures the right information in the forecast, while reliability measures the wrong information in the forecast. Furthermore, the new decomposition allows for a precise definition of the difference between estimated uncertainty (depending only on the ensemble) and actual uncertainty (depending on how the ensembles compare to the observations). It follows that a minimum actual uncertainty can only be achieved when the estimated uncertainty equals the actual. Because deterministic forecasts (unless perfect) do not satisfy this condition, they necessarily lead to a loss of information. This provides a clear case for the use of ensemble forecasts, which can now be evaluated using tools from information theory.

  18. A strategy for achieving high reliability for reusable launch vehicles (RLVs)

    NASA Astrophysics Data System (ADS)

    Sholtis, Joseph A.

    2002-01-01

    Expendable launch vehicles (ELVs) have been used since the early 1960s to put numerous payloads, including humans, into space. Yet, in spite of their widespread use since that time, ELV reliability has not improved much. Why has this been the case? And, more importantly, what might be done to substantially improve the reliability of future reusable launch vehicles (RLVs) to levels needed for commercial viability, i.e., approaching that of the U.S. commercial airline industry? This paper attempts to answer these questions-by reviewing the history of launch vehicles, identifying factors important to their reliability and safety, and in doing so, offering a potential strategy for achieving high RLV reliability. The conclusion reached is that there is every reason to believe that high reliability (~0.99999 per mission) is achievable for future RLVs, if key features to enhance their inherent robustness, forgiveness, and recoverability are considered and integrated into RLV design and operation at the outset. It is hoped that this paper will serve as a catalyst for further discussions intended to ensure that high reliability is realized for RLVs. .

  19. Validity, Reliability, and Utility of the Observation Survey of Early Literacy Achievement

    ERIC Educational Resources Information Center

    Denton, Carolyn A.; Ciancio, Dennis J.; Fletcher, Jack M.

    2006-01-01

    This study evaluated the validity, reliability, and utility of five of the six subtests of Clay's (2002) Observation Survey of Early Literacy Achievement (OS), including Letter Identification, Word Reading, Writing Vocabulary, Hearing and Recording Sounds in Words, and Text Reading. In addition to a review of studies providing assessment of the…

  20. Development of a Valid and Reliable Student-Achievement and Process-Skills Instrument

    ERIC Educational Resources Information Center

    Bunce, Diane M.; VandenPlas, Jessica R.; Neiles, Kelly Y.; Flens, Elizabeth A.

    2010-01-01

    Development of a research instrument to measure student achievement requires planning and reliability and validity testing before the instrument is used to collect data. These steps are often overlooked in research studies, but when the instrument is to be used across a wider population, the inclusion of these steps is vital to address the…

  1. Our Commitment to Reliable Health and Medical Information

    MedlinePlus

    ... below: The commitment to reliable health and medical information on the internet HON was founded to encourage the dissemination of ... and trustworthy code for medical and health related information available on Internet.The HONcode is designed for three target audiences: ...

  2. Modeling Achievement Trajectories when Attrition Is Informative

    ERIC Educational Resources Information Center

    Feldman, Betsy J.; Rabe-Hesketh, Sophia

    2012-01-01

    In longitudinal education studies, assuming that dropout and missing data occur completely at random is often unrealistic. When the probability of dropout depends on covariates and observed responses (called "missing at random" [MAR]), or on values of responses that are missing (called "informative" or "not missing at random" [NMAR]),…

  3. Using Information from Operating Experience to Inform Human Reliability Analysis

    SciTech Connect

    Bruce P. Hallbert; David I. Gertman; Julie Marble; Erasmia Lois; Nathan Siu

    2004-06-01

    This paper reports on efforts being sponsored by the U.S. NRC and performed by INEEL to develop a technical basis and perform work to extract information from sources for use in HRA. The objectives of this work are to: 1) develop a method for conducting risk-informed event analysis of human performance information that stems from operating experience at nuclear power plants and for compiling and documenting the results in a structured manner; 2) provide information from these analyses for use in risk-informed and performance-based regulatory activities; 3) create methods for information extraction and a repository for this information that, likewise, support HRA methods and their applications.

  4. The Reliability of Informal Reading Inventories: What Has Changed?

    ERIC Educational Resources Information Center

    Nilsson, Nina L.

    2013-01-01

    Over time, criticisms related to the technical rigor of informal reading inventories (IRIs) have led many to question using these assessment instruments for high- or low-stakes purposes. In this article, I examine reliability evidence reported in 11 new and updated IRIs and make comparisons with Spector's earlier analysis that revealed fewer…

  5. Reliability and Validity of Curriculum-Based Informal Reading Inventories.

    ERIC Educational Resources Information Center

    Fuchs, Lynn; And Others

    A study was conducted to explore the reliability and validity of three prominent procedures used in informal reading inventories (IRIs): (1) choosing a 95% word recognition accuracy standard for determining student instructional level, (2) arbitrarily selecting a passage to represent the difficulty level of a basal reader, and (3) employing…

  6. Quantifying neurotransmission reliability through metrics-based information analysis.

    PubMed

    Brasselet, Romain; Johansson, Roland S; Arleo, Angelo

    2011-04-01

    We set forth an information-theoretical measure to quantify neurotransmission reliability while taking into full account the metrical properties of the spike train space. This parametric information analysis relies on similarity measures induced by the metrical relations between neural responses as spikes flow in. Thus, in order to assess the entropy, the conditional entropy, and the overall information transfer, this method does not require any a priori decoding algorithm to partition the space into equivalence classes. It therefore allows the optimal parameters of a class of distances to be determined with respect to information transmission. To validate the proposed information-theoretical approach, we study precise temporal decoding of human somatosensory signals recorded using microneurography experiments. For this analysis, we employ a similarity measure based on the Victor-Purpura spike train metrics. We show that with appropriate parameters of this distance, the relative spike times of the mechanoreceptors' responses convey enough information to perform optimal discrimination--defined as maximum metrical information and zero conditional entropy--of 81 distinct stimuli within 40 ms of the first afferent spike. The proposed information-theoretical measure proves to be a suitable generalization of Shannon mutual information in order to consider the metrics of temporal codes explicitly. It allows neurotransmission reliability to be assessed in the presence of large spike train spaces (e.g., neural population codes) with high temporal precision. PMID:21222522

  7. Fair and Just Culture, Team Behavior, and Leadership Engagement: The Tools to Achieve High Reliability

    PubMed Central

    Frankel, Allan S; Leonard, Michael W; Denham, Charles R

    2006-01-01

    Background Disparate health care provider attitudes about autonomy, teamwork, and administrative operations have added to the complexity of health care delivery and are a central factor in medicine's unacceptably high rate of errors. Other industries have improved their reliability by applying innovative concepts to interpersonal relationships and administrative hierarchical structures (Chandler 1962). In the last 10 years the science of patient safety has become more sophisticated, with practical concepts identified and tested to improve the safety and reliability of care. Objective Three initiatives stand out as worthy regarding interpersonal relationships and the application of provider concerns to shape operational change: The development and implementation of Fair and Just Culture principles, the broad use of Teamwork Training and Communication, and tools like WalkRounds that promote the alignment of leadership and frontline provider perspectives through effective use of adverse event data and provider comments. Methods Fair and Just Culture, Teamwork Training, and WalkRounds are described, and implementation examples provided. The argument is made that they must be systematically and consistently implemented in an integrated fashion. Conclusions There are excellent examples of institutions applying Just Culture principles, Teamwork Training, and Leadership WalkRounds—but to date, they have not been comprehensively instituted in health care organizations in a cohesive and interdependent manner. To achieve reliability, organizations need to begin thinking about the relationship between these efforts and linking them conceptually. PMID:16898986

  8. Laboratory Information Management System Chain of Custody: Reliability and Security

    PubMed Central

    Tomlinson, J. J.; Elliott-Smith, W.; Radosta, T.

    2006-01-01

    A chain of custody (COC) is required in many laboratories that handle forensics, drugs of abuse, environmental, clinical, and DNA testing, as well as other laboratories that want to assure reliability of reported results. Maintaining a dependable COC can be laborious, but with the recent establishment of the criteria for electronic records and signatures by US regulatory agencies, laboratory information management systems (LIMSs) are now being developed to fully automate COCs. The extent of automation and of data reliability can vary, and FDA- and EPA-compliant electronic signatures and system security are rare. PMID:17671623

  9. Agreement, the f-measure, and reliability in information retrieval.

    PubMed

    Hripcsak, George; Rothschild, Adam S

    2005-01-01

    Information retrieval studies that involve searching the Internet or marking phrases usually lack a well-defined number of negative cases. This prevents the use of traditional interrater reliability metrics like the kappa statistic to assess the quality of expert-generated gold standards. Such studies often quantify system performance as precision, recall, and F-measure, or as agreement. It can be shown that the average F-measure among pairs of experts is numerically identical to the average positive specific agreement among experts and that kappa approaches these measures as the number of negative cases grows large. Positive specific agreement-or the equivalent F-measure-may be an appropriate way to quantify interrater reliability and therefore to assess the reliability of a gold standard in these studies. PMID:15684123

  10. Reliability of the Blessed Telephone Information-Memory-Concentration Test.

    PubMed

    Kawas, C; Karagiozis, H; Resau, L; Corrada, M; Brookmeyer, R

    1995-10-01

    In-person cognitive evaluations can be costly and labor intensive in geographically widespread populations. Reliable telephone instruments that screen for cognitive status would greatly facilitate epidemiologic and other longitudinal studies. We evaluated the reliability of the Blessed Information-Memory-Concentration (IMC) test when administered by telephone. Eighty-four subjects with a wide range of cognitive abilities were administered the Blessed IMC twice over a 3-week interval. Forty-nine of the subjects were administered the test both by telephone and in-person, and 35 of the subjects were tested twice by telephone. Spearman's rank correlation was used to compare scores of the different administrations (.96; P < .001) and to examine test-retest reliability (.96; P < .001). The Blessed Telephone IMC (TIMC) test exhibits excellent reliability both when compared to in-person administration as well as in test-retest results. The Blessed TIMC appears to be a practical instrument for population and longitudinal studies when in-person assessment is not feasible. PMID:8561839

  11. Health On the Net's 20 Years of Transparent and Reliable Health Information.

    PubMed

    Boyer, Célia; Appel, Ron D; Ball, Marion J; van Bemmel, Jan H; Bergmans, Jean-Paul; Carpentier, Michel; Hochstrasser, Denis; Lindberg, Donald; Miller, Randolph; Peterschmitt, Jean-Claude; Safran, Charlie; Thonnet, Michèle; Geissbühler, Antoine

    2016-01-01

    The Health On the Net Foundation (HON) was born in 1996, during the beginning of the World Wide Web, from a collective decision by health specialists, led by the late Jean-Raoul Scherrer, who anticipated the need for online trustworthy health information. Because the Internet is a free space that everyone shares, a search for quality information is like a shot in the dark: neither will reliably hit their target. Thus, HON was created to promote deployment of useful and reliable online health information, and to enable its appropriate and efficient use. Two decades on, HON is the oldest and most valued quality marker for online health information. The organization has maintained its reputation through dynamic measures, innovative endeavors and dedication to upholding key values and goals. This paper provides an overview of the HON Foundation, and its activities, challenges, and achievements over the years. PMID:27577475

  12. The Effect of Contiguity on Informational Achievement and Psychomotor Performance.

    ERIC Educational Resources Information Center

    Hudson, Donald W.

    Using a randomized block design and involving the participation of 73 fifth, sixth, and seventh grade pupils, this study sought to ascertain the relative effects of traditional, varied and integrated contiguity on the achievement of information content and the performance of a psychomotor task. The informational content selected for the study…

  13. Toward Obtaining Reliable Particulate Air Quality Information from Satellites

    NASA Astrophysics Data System (ADS)

    Strawa, A. W.; Chatfield, R. B.; Legg, M.; Esswein, R.; Justice, E.

    2009-12-01

    Air quality agencies use ground sites to monitor air quality, providing accurate information at particular points. Using measurements from satellite imagery has the potential to provide air quality information in a timely manner with better spatial resolution and at a lower cost that can also useful for model validation. While previous studies show acceptable correlations between Aerosol Optical Depth (AOD) derived from MODIS and surface Particulate Matter (PM) measurements on the eastern US, the data do not correlate well in the western US (Al-Saadi et al., 2005; Engle-Cox et al., 2004) . This paper seeks to improve the AOD-PM correlations by using advanced statistical analysis techniques. Our study area is the San Joaquin Valley in California because air quality in this region has failed to meet state and federal attainment standards for PM for the past several years. A previous investigation found good correlation of the AOD values between MODIS, MISR and AERONET, but poor correlations (R2 ~ 0.02) between satellite-based AOD and surface PM2.5 measurements. PM2.5 measurements correlated somewhat better (R2 ~ 0.18) with MODIS-derived AOD using the Deep Blue surface reflectance algorithm (Hsu et al., 2006) rather than the standard MODIS algorithm. This level of correlation is not adequate for reliable air quality measurements. Pelletier et al. (2007) used generalized additive models (GAMs) and meteorological data to improve the correlation between PM and AERONET AOD in western Europe. Additive models are more flexible than linear models and the functional relationships can be plotted to give a sense of the relationship between the predictor and the response. In this paper we use GAMs to improve surface PM2.5 to MODIS-AOD correlations. For example, we achieve an R2 ~ 0.44 using a GAM that includes the Deep Blue AOD, and day of year as parameters. Including NOx observations, improves the R2 ~ 0.64. Surprisingly Ångström exponent did not prove to be a significant

  14. The Stories Clinicians Tell: Achieving High Reliability and Improving Patient Safety

    PubMed Central

    Cohen, Daniel L; Stewart, Kevin O

    2016-01-01

    The patient safety movement has been deeply affected by the stories patients have shared that have identified numerous opportunities for improvements in safety. These stories have identified system and/or human inefficiencies or dysfunctions, possibly even failures, often resulting in patient harm. Although patients’ stories tell us much, less commonly heard are the stories of clinicians and how their personal observations regarding the environments they work in and the circumstances and pressures under which they work may degrade patient safety and lead to harm. If the health care industry is to function like a high-reliability industry, to improve its processes and achieve the outcomes that patients rightly deserve, then leaders and managers must seek and value input from those on the front lines—both clinicians and patients. Stories from clinicians provided in this article address themes that include incident identification, disclosure and transparency, just culture, the impact of clinical workload pressures, human factors liabilities, clinicians as secondary victims, the impact of disruptive and punitive behaviors, factors affecting professional morale, and personal failings. PMID:26580146

  15. Assessing readmission databases: how reliable is the information?

    PubMed

    Keeney, James A; Adelani, Muyibat A; Nunley, Ryan M; Clohisy, John C; Barrack, Robert L

    2012-09-01

    Databases are being used to shape health care policy. However, the reliability of coding information entered into the databases may be difficult to validate. In this study, we assess readmission data from an institutional database that identified 1515 readmissions (708 patients) after total hip or total knee arthroplasty during a 5-year interval. After exclusions, 223 readmissions (190 patients) underwent medical record review. Bleeding, wound-related, and arthroplasty-related complications constituted most (62.8%) of readmissions. Bleeding and wound complications were nearly 6 times more frequently associated with readmission than venous thromboembolism events. On secondary review, there was discordance between the diagnosis obtained by a surgeon reviewer and coding for diagnoses consistent with periprosthetic infection (996.66, 77, 78, and 998.59) in 70% of cases. The findings of our study raise questions regarding the validity of accepting information obtained from larger databases without closer scrutiny. PMID:22579350

  16. Resource reliability, accessibility and governance: pillars for managing water resources to achieve water security in Nepal

    NASA Astrophysics Data System (ADS)

    Biggs, E. M.; Duncan, J.; Atkinson, P.; Dash, J.

    2013-12-01

    As one of the world's most water-abundant countries, Nepal has plenty of water yet resources are both spatially and temporally unevenly distributed. With a population heavily engaged in subsistence farming, whereby livelihoods are entirely dependent on rain-fed agriculture, changes in freshwater resources can substantially impact upon survival. The two main sources of water in Nepal come from monsoon precipitation and glacial runoff. The former is essential for sustaining livelihoods where communities have little or no access to perennial water resources. Much of Nepal's population live in the southern Mid-Hills and Terai regions where dependency on the monsoon system is high and climate-environment interactions are intricate. Any fluctuations in precipitation can severely affect essential potable resources and food security. As the population continues to expand in Nepal, and pressures build on access to adequate and clean water resources, there is a need for institutions to cooperate and increase the effectiveness of water management policies. This research presents a framework detailing three fundamental pillars for managing water resources to achieve sustainable water security in Nepal. These are (i) resource reliability; (ii) adequate accessibility; and (iii) effective governance. Evidence is presented which indicates that water resources are adequate in Nepal to sustain the population. In addition, aspects of climate change are having less impact than previously perceived e.g. results from trend analysis of precipitation time-series indicate a decrease in monsoon extremes and interannual variation over the last half-century. However, accessibility to clean water resources and the potential for water storage is limiting the use of these resources. This issue is particularly prevalent given the heterogeneity in spatial and temporal distributions of water. Water governance is also ineffective due to government instability and a lack of continuity in policy

  17. Updating the reference population to achieve constant genomic prediction reliability across generations.

    PubMed

    Pszczola, M; Calus, M P L

    2016-06-01

    The reliability of genomic breeding values (DGV) decays over generations. To keep the DGV reliability at a constant level, the reference population (RP) has to be continuously updated with animals from new generations. Updating RP may be challenging due to economic reasons, especially for novel traits involving expensive phenotyping. Therefore, the goal of this study was to investigate a minimal RP update size to keep the reliability at a constant level across generations. We used a simulated dataset resembling a dairy cattle population. The trait of interest was not included itself in the selection index, but it was affected by selection pressure by being correlated with an index trait that represented the overall breeding goal. The heritability of the index trait was assumed to be 0.25 and for the novel trait the heritability equalled 0.2. The genetic correlation between the two traits was 0.25. The initial RP (n=2000) was composed of cows only with a single observation per animal. Reliability of DGV using the initial RP was computed by evaluating contemporary animals. Thereafter, the RP was used to evaluate animals which were one generation younger from the reference individuals. The drop in the reliability when evaluating younger animals was then assessed and the RP was updated to re-gain the initial reliability. The update animals were contemporaries of evaluated animals (EVA). The RP was updated in batches of 100 animals/update. First, the animals most closely related to the EVA were chosen to update RP. The results showed that, approximately, 600 animals were needed every generation to maintain the DGV reliability at a constant level across generations. The sum of squared relationships between RP and EVA and the sum of off-diagonal coefficients of the inverse of the genomic relationship matrix for RP, separately explained 31% and 34%, respectively, of the variation in the reliability across generations. Combined, these parameters explained 53% of the

  18. Is It Really Possible to Test All Educationally Significant Achievements with High Levels of Reliability?

    ERIC Educational Resources Information Center

    Davis, Andrew

    2015-01-01

    PISA claims that it can extend its reach from its current core subjects of Reading, Science, Maths and problem-solving. Yet given the requirement for high levels of reliability for PISA, especially in the light of its current high stakes character, proposed widening of its subject coverage cannot embrace some important aspects of the social and…

  19. Reliability and Validity of the "Achievement Emotions Questionnaire": A Study of Argentinean University Students

    ERIC Educational Resources Information Center

    Paoloni, Paola Verónica; Vaja, Arabela Beatriz; Muñoz, Verónica Lilian

    2014-01-01

    Introduction: This paper aims at describing the psychometric features of the Achievement Emotions Questionnaire (AEQ), focusing specifically on the section that measures class emotions. From a theoretical perspective, this instrument was designed based on the control-value theory of achievement emotions. Therefore, a description of the…

  20. The Information Function for the One-Parameter Logistic Model: Is it Reliability?

    ERIC Educational Resources Information Center

    Doran, Harold C.

    2005-01-01

    The information function is an important statistic in item response theory (IRT) applications. Although the information function is often described as the IRT version of reliability, it differs from the classical notion of reliability from a critical perspective: replication. This article first explores the information function for the…

  1. Testing the reliability of information extracted from ancient zircon

    NASA Astrophysics Data System (ADS)

    Kielman, Ross; Whitehouse, Martin; Nemchin, Alexander

    2015-04-01

    Studies combining zircon U-Pb chronology, trace element distribution as well as O and Hf isotope systematics are a powerful way to gain understanding of the processes shaping Earth's evolution, especially in detrital populations where constraints from the original host are missing. Such studies of the Hadean detrital zircon population abundant in sedimentary rocks in Western Australia have involved analysis of an unusually large number of individual grains, but also highlighted potential problems with the approach, only apparent when multiple analyses are obtained from individual grains. A common feature of the Hadean as well as many early Archaean zircon populations is their apparent inhomogeneity, which reduces confidence in conclusions based on studies combining chemistry and isotopic characteristics of zircon. In order to test the reliability of information extracted from early Earth zircon, we report results from one of the first in-depth multi-method study of zircon from a relatively simple early Archean magmatic rock, used as an analogue to ancient detrital zircon. The approach involves making multiple SIMS analyses in individual grains in order to be comparable to the most advanced studies of detrital zircon populations. The investigated sample is a relatively undeformed, non-migmatitic ca. 3.8 Ga tonalite collected a few kms south of the Isua Greenstone Belt, southwest Greenland. Extracted zircon grains can be combined into three different groups based on the behavior of their U-Pb systems: (i) grains that show internally consistent and concordant ages and define an average age of 3805±15 Ma, taken to be the age of the rock, (ii) grains that are distributed close to the concordia line, but with significant variability between multiple analyses, suggesting an ancient Pb loss and (iii) grains that have multiple analyses distributed along a discordia pointing towards a zero intercept, indicating geologically recent Pb-loss. This overall behavior has

  2. Reviewing Reliability and Validity of Information for University Educational Evaluation

    NASA Astrophysics Data System (ADS)

    Otsuka, Yusaku

    To better utilize evaluations in higher education, it is necessary to share the methods of reviewing reliability and validity of examination scores and grades, and to accumulate and share data for confirming results. Before the GPA system is first introduced into a university or college, the reliability of examination scores and grades, especially for essay examinations, must be assured. Validity is a complicated concept, so should be assured in various ways, including using professional audits, theoretical models, and statistical data analysis. Because individual students and teachers are continually improving, using evaluations to appraise their progress is not always compatible with using evaluations in appraising the implementation of accountability in various departments or the university overall. To better utilize evaluations and improve higher education, evaluations should be integrated into the current system by sharing the vision of an academic learning community and promoting interaction between students and teachers based on sufficiently reliable and validated evaluation tools.

  3. Technical information report: Plasma melter operation, reliability, and maintenance analysis

    SciTech Connect

    Hendrickson, D.W.

    1995-03-14

    This document provides a technical report of operability, reliability, and maintenance of a plasma melter for low-level waste vitrification, in support of the Hanford Tank Waste Remediation System (TWRS) Low-Level Waste (LLW) Vitrification Program. A process description is provided that minimizes maintenance and downtime and includes material and energy balances, equipment sizes and arrangement, startup/operation/maintence/shutdown cycle descriptions, and basis for scale-up to a 200 metric ton/day production facility. Operational requirements are provided including utilities, feeds, labor, and maintenance. Equipment reliability estimates and maintenance requirements are provided which includes a list of failure modes, responses, and consequences.

  4. A Summary of State Chapter 1 Migrant Education Program Participation and Achievement Information, 1986-87. Volume 2: Achievement.

    ERIC Educational Resources Information Center

    Henderson, Allison; And Others

    This report summarizes the achievement information provided by state educational agencies for the Migrant Education Program, 1986-87. Of the 34 states submitting achievement information for the regular term, 27 used norm-referenced tests, 9 used criterion-referenced tests, and 2 used locally developed instruments. Of the 15 states submitting…

  5. A Summary of State Chapter 1 Migrant Education Program Participation and Achievement Information for 1985-86. Volume 2: Achievement.

    ERIC Educational Resources Information Center

    Gutmann, Babette; And Others

    This report summarizes the achievement information provided by state educational agencies for the Migrant Education Program, 1985-86. Of the 34 states submitting achievement information for the regular term, 29 used norm-referenced tests, 10 used criterion-referenced tests, and 3 used locally developed instruments. Of the 15 states submitting…

  6. Achieving reliability - The evolution of redundancy in American manned spacecraft computers

    NASA Technical Reports Server (NTRS)

    Tomayko, J. E.

    1985-01-01

    The Shuttle is the first launch system deployed by NASA with full redundancy in the on-board computer systems. Fault-tolerance, i.e., restoring to a backup with less capabilities, was the method selected for Apollo. The Gemini capsule was the first to carry a computer, which also served as backup for Titan launch vehicle guidance. Failure of the Gemini computer resulted in manual control of the spacecraft. The Apollo system served vehicle flight control and navigation functions. The redundant computer on Skylab provided attitude control only in support of solar telescope pointing. The STS digital, fly-by-wire avionics system requires 100 percent reliability. The Orbiter carries five general purpose computers, four being fully-redundant and the fifth being soley an ascent-descent tool. The computers are synchronized at input and output points at a rate of about six times a second. The system is projected to cause a loss of an Orbiter only four times in a billion flights.

  7. Reliability training

    NASA Technical Reports Server (NTRS)

    Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Dillard, Richard B.; Wong, Kam L.; Barber, Frank J.; Barina, Frank J.

    1992-01-01

    Discussed here is failure physics, the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low cost reliable products. A review of reliability for the years 1940 to 2000 is given. Next, a review of mathematics is given as well as a description of what elements contribute to product failures. Basic reliability theory and the disciplines that allow us to control and eliminate failures are elucidated.

  8. Foraging Bumble Bees Weigh the Reliability of Personal and Social Information.

    PubMed

    Dunlap, Aimee S; Nielsen, Matthew E; Dornhaus, Anna; Papaj, Daniel R

    2016-05-01

    Many animals, including insects, make decisions using both personally gathered information and social information derived from the behavior of other, usually conspecific, individuals [1]. Moreover, animals adjust use of social versus personal information appropriately under a variety of experimental conditions [2-5]. An important factor in how information is used is the information's reliability, that is, how consistently the information is correlated with something of relevance in the environment [6]. The reliability of information determines which signals should be attended to during communication [6-9], which types of stimuli animals should learn about, and even whether learning should evolve [10, 11]. Here, we show that bumble bees (Bombus impatiens) account for the reliability of personally acquired information (which flower color was previously associated with reward) and social information (which flowers are chosen by other bees) in making foraging decisions; however, the two types of information are not treated equally. Bees prefer to use social information if it predicts a reward at all, but if social information becomes entirely unreliable, flower color will be used instead. This greater sensitivity to the reliability of social information, and avoidance of conspecifics in some cases, may reflect the specific ecological circumstances of bee foraging. Overall, the bees' ability to make decisions based on both personally acquired and socially derived information, and the relative reliability of both, demonstrates a new level of sophistication and flexibility in animal, particularly insect, decision-making. PMID:27133871

  9. Children Assess Informant Reliability Using Bystanders' Non-Verbal Cues

    ERIC Educational Resources Information Center

    Fusaro, Maria; Harris, Paul L.

    2008-01-01

    Recent findings show that preschool children are selective with respect to whom they ask for information and whose claims they endorse. In particular, they monitor an informant's record of past accuracy or inaccuracy and use that record to gauge future trustworthiness. We ask if preschoolers also monitor the non-verbal cues of assent or dissent…

  10. Impact of NDE reliability developments on risk-informed methods

    SciTech Connect

    Walker, S.M.; Ammirato, F.V.

    1996-12-01

    Risk informed inspection procedures are being developed to more effectively and economically manage degradation in plant piping systems. A key element of this process is applying nondestructive examination (NDE) procedures capable of detecting specific damage mechanisms that may be operative in particular locations. Thus, the needs of risk informed analysis are closely coupled with a firm understanding of the capability of NDE.

  11. Nine-spined sticklebacks exploit the most reliable source when public and private information conflict.

    PubMed Central

    van Bergen, Yfke; Coolen, Isabelle; Laland, Kevin N.

    2004-01-01

    Social foragers can potentially use private information gained from personal experience and public information gained from observing the foraging success of others to determine the profitability of a foraging patch. We investigated how nine-spined sticklebacks use conflicting public and private information of variable reliability to make foraging decisions. In a first experiment, when private information was reliable, sticklebacks ignored public information and based their foraging decision on private information. However, when private information was less reliable, sticklebacks tended to use public rather than private information. A second experiment investigated how the time since experiencing private information affected sticklebacks' use of this information when it conflicted with recent public information. Fish based their foraging decisions on recently acquired private information, but reliance on private information diminished as the period since experiencing it increased. Fish used public information if 7 days had elapsed since updating their private information. Our findings suggest that nine-spined sticklebacks flexibly adjust their decision making to exploit the most reliable information available, be it public or private, and that animals will weight private and public information appropriately depending on circumstances. PMID:15255051

  12. Parsing the Achievement Gap II. Policy Information Report

    ERIC Educational Resources Information Center

    Barton, Paul E.; Coley, Richard J.

    2009-01-01

    Gaps in school achievement among racial/ethnic groups and between students from different socioeconomic circumstances are well documented. They are wide and persistent, well known and widely acknowledged. This report focuses on the conditions and experiences that create and perpetuate achievement gaps. It is the second edition of the report…

  13. Individual differences in infants' information processing: reliability, stability, and prediction.

    PubMed

    Rose, S A; Feldman, J F; Wallace, I F

    1988-10-01

    A group of 46 full-term and 54 high-risk preterm (less than 1,500 grams birthweight) infants were tested at 6, 7, and/or 8 months of age (corrected age for preterms) on a battery of problems assessing visual recognition memory and tactual-visual cross-modal transfer. At all 3 ages, scores obtained on aggregates of 6-11 problems in the battery significantly predicted 3-year Stanford-Binet IQ: correlations ranged from r = .37 to r = .63, and clustered between r = .50 and r = .60. When aggregates from 2 or 3 ages were used as predictors, multiple correlations were as high as R = .60 and R = .70. Cutoffs for predicting children at risk for mental retardation (IQ less than 70) or cognitive delay (IQ less than 85) showed reasonable sensitivity and specificity, although low scores were poor at detecting IQs less than 70. The internal consistency of composites, indexed by alpha coefficients, was unexpectedly low, primarily because the problems shared little variance. However, stability coefficients between assessments as much as 1 and 2 months apart were moderate in magnitude, ranging from r = .30 to r = .50. Considering the high degree of predictive validity, the stability figures appear to be better estimates of reliability for these measures than are indices of internal consistency. The relations reported here were similar for both full-terms and preterms. PMID:3168635

  14. A Validity and Reliability Update on the Informal Reading Inventory with Suggestions for Improvement.

    ERIC Educational Resources Information Center

    Klesius, Janell P.; Homan, Susan P.

    1985-01-01

    The article reviews validity and reliability studies on the informal reading inventory, a diagnostic instrument to identify reading grade-level placement and strengths and weaknesses in work recognition and comprehension. Gives suggestions to improve the validity and reliability of existing inventories and to evaluate them in newly published…

  15. Reliability and information content of tests with cardioleader in cyclic types of sports

    NASA Technical Reports Server (NTRS)

    Utkin, V. L.

    1980-01-01

    Tests with cardioleader to control the physical, technical and tactical preparedness of athletes in cyclic types of sports are discussed. Ways of increasing the reliability and information content of the tests were studied.

  16. Effects of lecture information density on medical student achievement.

    PubMed

    Russell, I J; Hendricson, W D; Herbert, R J

    1984-11-01

    With the virtual explosion of biomedical information, the medical educator regularly faces a quandary regarding how much to include in the medical curriculum. Opinions differ regarding how much of the available information on a particular topic should be presented in a medical school lecture. To understand better the effect of lecture information density on learning by medical students, one of the authors gave a basic clinical lecture only or clinical lectures with varying amounts of semirelated information. Tests which measured only retention of the basic material were given before lecture attendance, immediately after the lecture, and 15 days later. The results indicated that increasing the information density of a lecture reduced retention of the basic information. The memory loss apparently was due to information presented late in the lecture displacing facts learned by the students earlier in the same hour. The data suggest that lectures to medical students are more effective aids to learning when the information density is limited to a few main points that are "essential to know." PMID:6492106

  17. Community First Communication: Reversing Information Disparities to Achieve Environmental Justice

    PubMed Central

    Emmett, Edward A.; Desai, Chintan

    2011-01-01

    We address how information developed and effectively communicated through community based participatory research (CBPR) can reverse long-standing information disparities, empower a community, and be an agent for sustained change. Substantial information and power disparities existed between the polluted community and both the pollution industry and governmental regulators. An environmental justice partnership between a local community organization, physicians, and university performed CBPR and then developed a novel communication strategy to address a series of information disparities around a local water pollution issue. The community established a set of principles to govern the communication of results as soon as they were determined to be scientifically valid, including informing study participants and the community before other interested parties. CBPR results combined with a community-first communication strategy reversed the preexisting information disparities. The novel communication flow reversed the preferential information flow to industry and government associated with the usual scientific publication process. The community was empowered, and industry and government agencies responded positively to study recommendations. The CBPR results together with community first communication led to adoption of both community-wide and individual solutions and provided powerful motivation for behavioral change by industry and residents. PMID:21546988

  18. Integrating Health Information Technology to Achieve Seamless Care Transitions.

    PubMed

    Marcotte, Leah; Kirtane, Janhavi; Lynn, Joanne; McKethan, Aaron

    2015-12-01

    Improving care transitions, or "handoffs" as patients migrate from one care setting to another, is a priority across stakeholder groups and health-care settings and additionally is included in national health-care goals set forth in the National Quality Strategy. Although many demonstrations of improved care transitions have succeeded, particularly for hospital discharges, ensuring consistent, high-quality, and safe transitions of care remains challenging. This paper highlights the potential for health information technology to become an increasing part of effective transitional care interventions, with the potential to reduce the resource burden currently associated with effective care transitions, the ability to spread improved practices to larger numbers of patients and providers efficiently and at scale, and, as health technology interoperability increases, the potential to facilitate critical information flow and feedback loops to clinicians, patients, and caregivers across disparate information systems and care settings. PMID:24522208

  19. The Achievement of Therapeutic Objectives Scale: Interrater Reliability and Sensitivity to Change in Short-Term Dynamic Psychotherapy and Cognitive Therapy

    ERIC Educational Resources Information Center

    Valen, Jakob; Ryum, Truls; Svartberg, Martin; Stiles, Tore C.; McCullough, Leigh

    2011-01-01

    This study examined interrater reliability and sensitivity to change of the Achievement of Therapeutic Objectives Scale (ATOS; McCullough, Larsen, et al., 2003) in short-term dynamic psychotherapy (STDP) and cognitive therapy (CT). The ATOS is a process scale originally developed to assess patients' achievements of treatment objectives in STDP,…

  20. Informational and Dispositional Determinants of Children's Achievement Attributions

    ERIC Educational Resources Information Center

    Ames, Carole; And Others

    1976-01-01

    Results show that consistency of student performance was related to both the stability dimension of attributional behavior and attributions for immediate outcome varied along the locus of control dimension. Findings suggest the dominance of an informationally oriented influence on attributional behavior. (BJG)

  1. Consultation and Reliability of Information Sources Pertaining to University Selection: Some Questions Answered?

    ERIC Educational Resources Information Center

    Veloutsou, Cleopatra; Paton, Robert A.; Lewis, John

    2005-01-01

    Purpose: This paper aims to explore the information sources used by school leavers when selecting a university at which they wish to study and the perceived reliability of these sources of information. Design/methodology/approach: Using data from 306 pupils studying at various schools in England, Scotland and Northern Ireland it was revealed that…

  2. Perception of reliability of human immunodeficiency virus/AIDS information sources.

    PubMed Central

    Essien, E. J.; Ross, M. W.; Linares, A. C.; Osemene, N. I.

    2000-01-01

    The sources of human immunodeficiency virus (HIV)/AIDS information as well as the perception of reliability of information from these sources may have a significant impact on the effectiveness of HIV risk reduction messages in reaching high risk populations. We examined the sources of HIV information and the perception of reliability of information from these sources among African Americans (n = 441), Hispanic Americans (n = 456), and whites (n = 297), in Houston, Texas. The data revealed that African Americans and Hispanics were most likely to receive their HIV/AIDS information from the "media" compared with whites who received most of their information from "government agencies and professionals." Information from "family, friends and schools" were regarded as the least reliable by respondents from all three ethnic groups. The data also showed that perceptions of reliability of information sources were influenced by level of educational attainment. Implications for designing target audience-specific intervention strategies for the prevention of the spread of HIV disease are discussed. PMID:10918761

  3. Reading Information about a Scientific Phenomenon on Webpages Varying for Reliability: An Eye-Movement Analysis

    ERIC Educational Resources Information Center

    Mason, Lucia; Pluchino, Patrik; Ariasi, Nicola

    2014-01-01

    Students search the Web frequently for many purposes, one of which is to search information for academic assignments. Given the huge amount of easily accessible online information, they are required to develop new reading skills and become more able to effectively evaluate the reliability of web sources. This study investigates the distribution of…

  4. Probabilistic framework for reliability analysis of information-theoretic CAD systems in mammography.

    PubMed

    Habas, Piotr A; Zurada, Jacek M; Elmaghraby, Adel S; Tourassi, Georgia D

    2006-01-01

    The purpose of this study is to develop and evaluate a probabilistic framework for reliability analysis of information-theoretic computer-assisted detection (IT-CAD) systems in mammography. The study builds upon our previous work on a feature-based reliability analysis technique tailored to traditional CAD systems developed with a supervised learning scheme. The present study proposes a probabilistic framework to facilitate application of the reliability analysis technique for knowledge-based CAD systems that are not feature-based. The study was based on an information-theoretic CAD system developed for detection of masses in screening mammograms from the Digital Database for Screening Mammography (DDSM). The experimental results reveal that the query-specific reliability estimate provided by the proposed probabilistic framework is an accurate predictor of CAD performance for the query case. It can also be successfully applied as a base for stratification of CAD predictions into clinically meaningful reliability groups (i.e., HIGH, MEDIUM, and LOW). Based on a leave-one-out sampling scheme and ROC analysis, the study demonstrated that the diagnostic performance of the IT-CAD is significantly higher for cases with HIGH reliability (A(z) = 0.92 +/- 0.03) than for those stratified as MEDIUM (A(z) = 0.84 +/- 0.02) or LOW reliability predictions (A(z) = 0.78 +/- 0.02). PMID:17946741

  5. MyOcean Information System : achievements and perspectives

    NASA Astrophysics Data System (ADS)

    Loubrieu, T.; Dorandeu, J.; Claverie, V.; Cordier, K.; Barzic, Y.; Lauret, O.; Jolibois, T.; Blower, J.

    2012-04-01

    MyOcean system (http://www.myocean.eu) objective is to provide a Core Service for the Ocean. This means MyOcean is setting up an operational service for forecasts, analysis and expertise on ocean currents, temperature, salinity, sea level, primary ecosystems and ice coverage. The production of observation and forecasting data is distributed through 12 production centres. The interface with the external users (including web portal) and the coordination of the overall service is managed by a component called service desk. Besides, a transverse component called MIS (myOcean Information System) aims at connecting the production centres and service desk together, manage the shared information for the overall system and implement a standard Inspire interface for the external world. 2012 is a key year for the system. The MyOcean, 3-year project, which has set up the first versions of the system is ending. The MyOcean II, 2-year project, which will upgrade and consolidate the system is starting. Both projects are granted by the European commission within the GMES Program (7th Framework Program). At the end of the MyOcean project, the system has been designed and the 2 first versions have been implemented. The system now offers an integrated service composed with 237 ocean products. The ocean products are homogeneously described in a catalogue. They can be visualized and downloaded by the user (identified with a unique login) through a seamless web interface. The discovery and viewing interfaces are INSPIRE compliant. The data production, subsystems availability and audience are continuously monitored. The presentation will detail the implemented information system architecture and the chosen software solutions. Regarding the information system, MyOcean II is mainly aiming at consolidating the existing functions and promoting the operations cost-effectiveness. In addition, a specific effort will be done so that the less common data features of the system (ocean in

  6. Reliability of Health Information on the Internet: An Examination of Experts' Ratings

    PubMed Central

    Craigie, Mark; Loader, Brian; Burrows, Roger

    2002-01-01

    Background The use of medical experts in rating the content of health-related sites on the Internet has flourished in recent years. In this research, it has been common practice to use a single medical expert to rate the content of the Web sites. In many cases, the expert has rated the Internet health information as poor, and even potentially dangerous. However, one problem with this approach is that there is no guarantee that other medical experts will rate the sites in a similar manner. Objectives The aim was to assess the reliability of medical experts' judgments of threads in an Internet newsgroup related to a common disease. A secondary aim was to show the limitations of commonly-used statistics for measuring reliability (eg, kappa). Method The participants in this study were 5 medical doctors, who worked in a specialist unit dedicated to the treatment of the disease. They each rated the information contained in newsgroup threads using a 6-point scale designed by the experts themselves. Their ratings were analyzed for reliability using a number of statistics: Cohen's kappa, gamma, Kendall's W, and Cronbach's alpha. Results Reliability was absent for ratings of questions, and low for ratings of responses. The various measures of reliability used gave conflicting results. No measure produced high reliability. Conclusions The medical experts showed a low agreement when rating the postings from the newsgroup. Hence, it is important to test inter-rater reliability in research assessing the accuracy and quality of health-related information on the Internet. A discussion of the different measures of agreement that could be used reveals that the choice of statistic can be problematic. It is therefore important to consider the assumptions underlying a measure of reliability before using it. Often, more than one measure will be needed for "triangulation" purposes. PMID:11956034

  7. MyOcean Central Information System - Achievements and Perspectives

    NASA Astrophysics Data System (ADS)

    de Dianous, Rémi; Jolibois, Tony; Besnard, Sophie

    2015-04-01

    MyOcean (http://www.myocean.eu) is providing a pre-operational service, for forecasts, analysis and expertise on ocean currents, temperature, salinity, sea level, primary ecosystems and ice coverage. Since 2009, three successive projects (MyOcean-I, MyOcean-II and MyOcean-Follow-on) have been designed to prepare and to lead the demonstration phases of the future Copernicus Marine Environment Monitoring Service. The main goal of these projects was to build a system of systems offering the users a unique access point to European oceanographic data. Reaching this goal at European level with 59 partners from 28 different countries was a real challenge: initially, each local system had its own human processes and methodology, its own interfaces for production and dissemination. At the end of MyOcean Follow-on, any user can connect to one web portal, browse an interactive catalogue of products and services, use one login to access all data disseminated through harmonized interfaces in a common format and contact a unique centralized service desk. In this organization the central information system plays a key role. The production of observation and forecasting data is done by 48 Production Units (PU). Product download and visualisation are hosted by 26 Dissemination Units (DU). All these products and associated services are gathered in a single system hiding the intricate distributed organization of PUs and DUs. This central system will be presented in detail, including notably the technical choices in architecture and technologies which have been made and why, and the lessons learned during these years of real life of the system, taking into account internal and external feedbacks. Then, perspectives will be presented to sketch the future of such system in the next Marine Copernicus Service which is meant to be fully operational from 2015 onwards.

  8. The Impact of Third-Party Information on Trust: Valence, Source, and Reliability

    PubMed Central

    2016-01-01

    Economic exchange between strangers happens extremely frequently due to the growing number of internet transactions. In trust situations like online transactions, a trustor usually does not know whether she encounters a trustworthy trustee. However, the trustor might form beliefs about the trustee's trustworthiness by relying on third-party information. Different kinds of third-party information can vary dramatically in their importance to the trustor. We ran a factorial design to study how the different characteristics of third-party information affect the trustor’s decision to trust. We systematically varied unregulated third-party information regarding the source (friend or a stranger), the reliability (gossip or experiences), and the valence (positive or negative) of the information. The results show that negative information is more salient for withholding trust than positive information is for placing trust. If third-party information is positive, experience of a friend has the strongest effect on trusting followed by friend’s gossip. Positive information from a stranger does not matter to the trustor. With respect to negative information, the data show that even the slightest hint of an untrustworthy trustee leads to significantly less placed trust irrespective of the source or the reliability of the information. PMID:26882013

  9. The Impact of Third-Party Information on Trust: Valence, Source, and Reliability.

    PubMed

    Bozoyan, Christiane; Vogt, Sonja

    2016-01-01

    Economic exchange between strangers happens extremely frequently due to the growing number of internet transactions. In trust situations like online transactions, a trustor usually does not know whether she encounters a trustworthy trustee. However, the trustor might form beliefs about the trustee's trustworthiness by relying on third-party information. Different kinds of third-party information can vary dramatically in their importance to the trustor. We ran a factorial design to study how the different characteristics of third-party information affect the trustor's decision to trust. We systematically varied unregulated third-party information regarding the source (friend or a stranger), the reliability (gossip or experiences), and the valence (positive or negative) of the information. The results show that negative information is more salient for withholding trust than positive information is for placing trust. If third-party information is positive, experience of a friend has the strongest effect on trusting followed by friend's gossip. Positive information from a stranger does not matter to the trustor. With respect to negative information, the data show that even the slightest hint of an untrustworthy trustee leads to significantly less placed trust irrespective of the source or the reliability of the information. PMID:26882013

  10. The Effects of Concealing Academic Achievement Information on Adolescents' Self-Concept

    ERIC Educational Resources Information Center

    Zhang, Baoshan; Wang, Mo; Li, Juan; Yu, Guoliang; Bi, Yan-Ling

    2011-01-01

    Using an experimental design, the effect of concealing academic achievement information on adolescents' self-concept was examined in the current study. Specifically, adolescents with low academic achievement and adolescents with average to high academic achievement (N = 129) were randomly assigned to different interview contexts wherein…

  11. Teacher Feedback and Student Academic Achievement: Teacher Use of Student Information Systems

    ERIC Educational Resources Information Center

    Bishop, Daniel J.

    2013-01-01

    In an era of professional standards for educators and teacher evaluations linked to measures of student achievement, researchers use data from student information systems to address research questions linking teacher feedback to student achievement. A quantitative study of teacher use of the Skyward student information system (SIS) was conducted…

  12. Validity of Assessment and Recognition of Non-Formal and Informal Learning Achievements in Higher Education

    ERIC Educational Resources Information Center

    Kaminskiene, Lina; Stasiunaitiene, Egle

    2013-01-01

    The article identifies the validity of assessment of non-formal and informal learning achievements (NILA) as one of the key factors for encouraging further development of the process of assessing and recognising non-formal and informal learning achievements in higher education. The authors analyse why the recognition of non-formal and informal…

  13. Digital Avionics Information System (DAIS): Reliability and Maintainability Model. Final Report.

    ERIC Educational Resources Information Center

    Czuchry, Andrew J.; And Others

    The reliability and maintainability (R&M) model described in this report represents an important portion of a larger effort called the Digital Avionics Information System (DAIS) Life Cycle Cost (LCC) Study. The R&M model is the first of three models that comprise a modeling system for use in LCC analysis of avionics systems. The total system will…

  14. Operation reliability assessment for cutting tools by applying a proportional covariate model to condition monitoring information.

    PubMed

    Cai, Gaigai; Chen, Xuefeng; Li, Bing; Chen, Baojia; He, Zhengjia

    2012-01-01

    The reliability of cutting tools is critical to machining precision and production efficiency. The conventional statistic-based reliability assessment method aims at providing a general and overall estimation of reliability for a large population of identical units under given and fixed conditions. However, it has limited effectiveness in depicting the operational characteristics of a cutting tool. To overcome this limitation, this paper proposes an approach to assess the operation reliability of cutting tools. A proportional covariate model is introduced to construct the relationship between operation reliability and condition monitoring information. The wavelet packet transform and an improved distance evaluation technique are used to extract sensitive features from vibration signals, and a covariate function is constructed based on the proportional covariate model. Ultimately, the failure rate function of the cutting tool being assessed is calculated using the baseline covariate function obtained from a small sample of historical data. Experimental results and a comparative study show that the proposed method is effective for assessing the operation reliability of cutting tools. PMID:23201980

  15. Operation Reliability Assessment for Cutting Tools by Applying a Proportional Covariate Model to Condition Monitoring Information

    PubMed Central

    Cai, Gaigai; Chen, Xuefeng; Li, Bing; Chen, Baojia; He, Zhengjia

    2012-01-01

    The reliability of cutting tools is critical to machining precision and production efficiency. The conventional statistic-based reliability assessment method aims at providing a general and overall estimation of reliability for a large population of identical units under given and fixed conditions. However, it has limited effectiveness in depicting the operational characteristics of a cutting tool. To overcome this limitation, this paper proposes an approach to assess the operation reliability of cutting tools. A proportional covariate model is introduced to construct the relationship between operation reliability and condition monitoring information. The wavelet packet transform and an improved distance evaluation technique are used to extract sensitive features from vibration signals, and a covariate function is constructed based on the proportional covariate model. Ultimately, the failure rate function of the cutting tool being assessed is calculated using the baseline covariate function obtained from a small sample of historical data. Experimental results and a comparative study show that the proposed method is effective for assessing the operation reliability of cutting tools. PMID:23201980

  16. Reliability and Validity Evidence of Scores on the Achievement Goal Tendencies Questionnaire in a Sample of Spanish Students of Compulsory Secondary Education

    ERIC Educational Resources Information Center

    Ingles, Candido J.; Garcia-Fernandez, Jose M.; Castejon, Juan L.; Valle, Antonio; Delgado, Beatriz; Marzo, Juan C.

    2009-01-01

    This study examined the reliability and validity evidence drawn from the scores of the Spanish version of the Achievement Goal Tendencies Questionnaire (AGTQ) using a sample of 2,022 (51.1% boys) Spanish students from grades 7 to 10. Confirmatory factor analysis replicated the correlated three-factor structure of the AGTQ in this sample: Learning…

  17. Creation of Reliable Relevance Judgments in Information Retrieval Systems Evaluation Experimentation through Crowdsourcing: A Review

    PubMed Central

    Samimi, Parnia; Ravana, Sri Devi

    2014-01-01

    Test collection is used to evaluate the information retrieval systems in laboratory-based evaluation experimentation. In a classic setting, generating relevance judgments involves human assessors and is a costly and time consuming task. Researchers and practitioners are still being challenged in performing reliable and low-cost evaluation of retrieval systems. Crowdsourcing as a novel method of data acquisition is broadly used in many research fields. It has been proven that crowdsourcing is an inexpensive and quick solution as well as a reliable alternative for creating relevance judgments. One of the crowdsourcing applications in IR is to judge relevancy of query document pair. In order to have a successful crowdsourcing experiment, the relevance judgment tasks should be designed precisely to emphasize quality control. This paper is intended to explore different factors that have an influence on the accuracy of relevance judgments accomplished by workers and how to intensify the reliability of judgments in crowdsourcing experiment. PMID:24977172

  18. Pre-Proposal Assessment of Reliability for Spacecraft Docking with Limited Information

    NASA Technical Reports Server (NTRS)

    Brall, Aron

    2013-01-01

    This paper addresses the problem of estimating the reliability of a critical system function as well as its impact on the system reliability when limited information is available. The approach addresses the basic function reliability, and then the impact of multiple attempts to accomplish the function. The dependence of subsequent attempts on prior failure to accomplish the function is also addressed. The autonomous docking of two spacecraft was the specific example that generated the inquiry, and the resultant impact on total reliability generated substantial interest in presenting the results due to the relative insensitivity of overall performance to basic function reliability and moderate degradation given sufficient attempts to try and accomplish the required goal. The application of the methodology allows proper emphasis on the characteristics that can be estimated with some knowledge, and to insulate the integrity of the design from those characteristics that can't be properly estimated with any rational value of uncertainty. The nature of NASA's missions contains a great deal of uncertainty due to the pursuit of new science or operations. This approach can be applied to any function where multiple attempts at success, with or without degradation, are allowed.

  19. Use and perceptions of information among family physicians: sources considered accessible, relevant, and reliable

    PubMed Central

    Kosteniuk, Julie G.; Morgan, Debra G.; D'Arcy, Carl K.

    2013-01-01

    Objectives: The research determined (1) the information sources that family physicians (FPs) most commonly use to update their general medical knowledge and to make specific clinical decisions, and (2) the information sources FPs found to be most physically accessible, intellectually accessible (easy to understand), reliable (trustworthy), and relevant to their needs. Methods: A cross-sectional postal survey of 792 FPs and locum tenens, in full-time or part-time medical practice, currently practicing or on leave of absence in the Canadian province of Saskatchewan was conducted during the period of January to April 2008. Results: Of 666 eligible physicians, 331 completed and returned surveys, resulting in a response rate of 49.7% (331/666). Medical textbooks and colleagues in the main patient care setting were the top 2 sources for the purpose of making specific clinical decisions. Medical textbooks were most frequently considered by FPs to be reliable (trustworthy), and colleagues in the main patient care setting were most physically accessible (easy to access). Conclusions: When making specific clinical decisions, FPs were most likely to use information from sources that they considered to be reliable and generally physically accessible, suggesting that FPs can best be supported by facilitating easy and convenient access to high-quality information. PMID:23405045

  20. Interventions to Assist Health Consumers to Find Reliable Online Health Information: A Comprehensive Review

    PubMed Central

    Lee, Kenneth; Hoti, Kreshnik; Hughes, Jeffery D.; Emmerton, Lynne M.

    2014-01-01

    Background Health information on the Internet is ubiquitous, and its use by health consumers prevalent. Finding and understanding relevant online health information, and determining content reliability, pose real challenges for many health consumers. Purpose To identify the types of interventions that have been implemented to assist health consumers to find reliable online health information, and where possible, describe and compare the types of outcomes studied. Data Sources PubMed, PsycINFO, CINAHL Plus and Cochrane Library databases; WorldCat and Scirus ‘gray literature’ search engines; and manual review of reference lists of selected publications. Study Selection Publications were selected by firstly screening title, abstract, and then full text. Data Extraction Seven publications met the inclusion criteria, and were summarized in a data extraction form. The form incorporated the PICOS (Population Intervention Comparators Outcomes and Study Design) Model. Two eligible gray literature papers were also reported. Data Synthesis Relevant data from included studies were tabulated to enable descriptive comparison. A brief critique of each study was included in the tables. This review was unable to follow systematic review methods due to the paucity of research and humanistic interventions reported. Limitations While extensive, the gray literature search may have had limited reach in some countries. The paucity of research on this topic limits conclusions that may be drawn. Conclusions The few eligible studies predominantly adopted a didactic approach to assisting health consumers, whereby consumers were either taught how to find credible websites, or how to use the Internet. Common types of outcomes studied include knowledge and skills pertaining to Internet use and searching for reliable health information. These outcomes were predominantly self-assessed by participants. There is potential for further research to explore other avenues for assisting health

  1. Increasing the Reliability of Ability-Achievement Difference Scores: An Example Using the Kaufman Assessment Battery for Children.

    ERIC Educational Resources Information Center

    Caruso, John C.; Witkiewitz, Katie

    2002-01-01

    As an alternative to equally weighted difference scores, examined an orthogonal reliable component analysis (RCA) solution and an oblique principal components analysis (PCA) solution for the standardization sample of the Kaufman Assessment Battery for Children (KABC; A. Kaufman and N. Kaufman, 1983). Discusses the practical implications of the…

  2. Protecting Quantum Dot Fluorescence from Quenching to Achieve a Reliable Automated Multiplex Fluorescence In Situ Hybridization Assay.

    PubMed

    Zhang, Wenjun; Hubbard, Antony; Pang, Lizhen; Parkinson, Leslie Baca; Brunhoeber, Patrick; Wang, Yixin; Tang, Lei

    2015-09-01

    Quantum dots (QD) are novel inorganic fluorochromes that are ultra-bright, photo-stable, and available in multiple, highly-resolvable colors. QDs represent an ideal detection material for in situ hybridization (ISH) because they may provide unprecedented resolution and strong signal intensities that are not attainable with traditional fluorophores. Unfortunately, lack of reliability has been an impediment to widespread adoption of QD-based fluorescence in situ hybridization (QD FISH) technology. By optimizing QD-to-target accessibility, we have developed a QD FISH staining procedure that dramatically improves the reliability of an automated ERG/PTEN QD FISH assay (91% 1st pass rate). Here, we report improvements to the assay that protects QD fluorescence from quenching due to trace amounts of heavy metals and minimizes QD background signals. When using this method, highly-consistent staining was observed with the ERG/PTEN QD FISH assay in prostate tissue. Successful staining of several other clinically-relevant genetic markers was also possible. We further demonstrated improved reliability for determining HER2 gene status in breast cancer, identifying anaplastic lymphoma kinase (ALK) gene break-apart in non-small cell lung cancer, and detecting human papillomavirus 16 (HPV16) in cervical intraepithelial neoplasia. The enhanced QD FISH assay allows for examining complicated genetic aberrances without use of enzymatic amplification. Our optimized methods now demonstrate reliability sufficient for QD FISH technology to be a diagnostic tool in a clinical setting. PMID:26485928

  3. Factors Associated with Low Achievement among Students from Nairobi's Urban Informal Neighborhoods

    ERIC Educational Resources Information Center

    Ejakait, Epari; Mutisya, Maurice; Ezeh, Alex; Oketch, Moses; Ngware, Moses

    2011-01-01

    This article contributes new evidence on factors associated with low achievement among pupils in urban informal neighborhoods in Nairobi, Kenya. The authors use three different data sets to examine the effect of residence in particular neighborhoods, pupil gender, primary school type, and household socioeconomic status on pupil achievement in the…

  4. Finding Ways to Effectively Use Year 12 Achievement Data to Inform Practice in Secondary Schools

    ERIC Educational Resources Information Center

    Italiano, Frank; Hine, Gregory

    2014-01-01

    This action research explored how Year 12 achievement data were used by school personnel to inform practice within seven Catholic secondary schools. Deputy Principals of Curriculum from participating schools were interviewed regarding their perceptions of the improvement of Year 12 student achievement outcomes, and their insights into how to…

  5. The Effect of Creative Drama on Student Achievement in the Course of Information Technologies

    ERIC Educational Resources Information Center

    Özek, Müzeyyen Bulut

    2016-01-01

    The purpose of this study is to determine the effect of creative drama on student achievement in the Information Technologies course. The study was carried out for the unit "Tomorrow's Technology" which is the first unit of Information Technologies course. For this study, 89 sixth grade students were selected from primary school in…

  6. Out-of-School Factors Affecting Academic Achievement. Information Capsule. Volume 1004

    ERIC Educational Resources Information Center

    Romanik, Dale

    2010-01-01

    This Information Capsule is the third in a series of papers addressing factors contributing to low academic achievement. The two previous papers addressed issues relevant to class size reduction and teacher quality/preparation. The premise of this Information Capsule is that there is no single smoking gun relative to improving school performance.…

  7. The minimization of inter-module interface for the achievement of reliability of multi-version software

    NASA Astrophysics Data System (ADS)

    Kovalev, I.; Zelenkov, P.; Ognerubov, S.

    2015-01-01

    This article shows that the use of the modular principle for the stage of technical designing of multi-version software is connected to the optimization process of the structure and interaction of its components. The new problem definition of the designing of the multi-version, modular structure of software, which provides the minimization of inter-module interface, is presented. This problem definition allows us to create the multi-version set of components which are used in software in the predefined sequences as well as in the random sequences. Simultaneously, the set of versions matches the predefined conditions, providing the maximum reliability for personal computers and the minimal values of the attributes of the inter-module interface.

  8. Adapting the Content of Cancer Web Sites to the Information Needs of Patients: Reliability and Readability

    PubMed Central

    Bermúdez-Tamayo, Clara; Pernett, Jaime Jiménez; Garcia-Gutierrez, Jose Francisco; Cózar-Olmo, José Manuel; Valero-Aguilera, Beatriz

    2013-01-01

    Abstract Background: People who use the Internet to research health topics do not usually find all the information they need and do not trust what they read. This study was designed to assess the reliability, accessibility, readability, and popularity of cancer Web sites in Spanish and to analyze the suitability of Web site content in accordance with the specific information needs of cancer patients. Materials and Methods: This was a two-phase, cross-sectional, descriptive study. The first phase involved data gathering through online searches and direct observation. The second phase involved individual structured interviews with 169 patients with breast, prostate, bladder, and kidney cancer. Spearman rank correlations were calculated between variables. Results: Most sites belonged to nonprofit organizations, followed by universities or medical centers (14%). Thirty-one percent of the Web sites had quality seals, 59% provided details of authorship, 62% provided references to bibliographic sources, 38% identified their funding sources, and 54% showed the date of their last update. Twenty-one percent of the Web sites did not meet the minimum accessibility criteria. With regard to readability, 24% of the texts were considered to be “quite difficult.” Patients' information needs vary depending on the type of cancer they have, although all patients want to know about the likelihood of a cure, survival rates, the side effects, and risks of treatment. Conclusions: The health information on cancer available on the Internet in Spanish is not very reliable, accessible, or readable and is not necessarily the information that breast, kidney, prostate, and bladder cancer patients require. The content of cancer Web sites needs to be assessed according to the information needs of patients. PMID:24073899

  9. The Accessibility, Usability, and Reliability of Chinese Web-Based Information on HIV/AIDS

    PubMed Central

    Niu, Lu; Luo, Dan; Liu, Ying; Xiao, Shuiyuan

    2016-01-01

    Objective: The present study was designed to assess the quality of Chinese-language Internet-based information on HIV/AIDS. Methods: We entered the following search terms, in Chinese, into Baidu and Sogou: “HIV/AIDS”, “symptoms”, and “treatment”, and evaluated the first 50 hits of each query using the Minervation validation instrument (LIDA tool) and DISCERN instrument. Results: Of the 900 hits identified, 85 websites were included in this study. The overall score of the LIDA tool was 63.7%; the mean score of accessibility, usability, and reliability was 82.2%, 71.5%, and 27.3%, respectively. Of the top 15 sites according to the LIDA score, the mean DISCERN score was calculated at 43.1 (95% confidence intervals (CI) = 37.7–49.5). Noncommercial websites showed higher DISCERN scores than commercial websites; whereas commercial websites were more likely to be found in the first 20 links obtained from each search engine than the noncommercial websites. Conclusions: In general, the HIV/AIDS related Chinese-language websites have poor reliability, although their accessibility and usability are fair. In addition, the treatment information presented on Chinese-language websites is far from sufficient. There is an imperative need for professionals and specialized institutes to improve the comprehensiveness of web-based information related to HIV/AIDS. PMID:27556475

  10. The application of Plant Reliability Data Information System (PRINS) to CANDU reactor

    SciTech Connect

    Hwang, S. W.; Lim, Y. H.; Park, H. C.

    2012-07-01

    As risk-informed applications (RIAs) are actively implanted in the nuclear industry, an issue associated with technical adequacy of Probabilistic Safety Assessment (PSA) arises in its modeling and data sourcing. In Korea, PSA for all Korean NPPs has been completed and KHNP(Korea Hydro and Nuclear Power Plant Company) developed the database called the Plant Reliability Data Information System (PRinS). It has several characteristics that distinguish it from other database system such as NPRDs (INPO,1994), PRIS (IAEA), and SRDF (EdF). This database has the function of systematic data management such as automatic data-gathering, periodic data deposition and updating, statistical analysis including Bayesian method, and trend analysis of failure rate or unavailability. In recent PSA for CANDU reactor, the component failure data of EPRI ALWR URD and Component Reliability Database were preferentially used as generic data set. The error factor for most component failure data was estimated by using the information NUREG/CR-4550 and NUREG/CR-4639. Also, annual trend analysis was performed for the functional losses of components using the statistical analysis and chart module of PRinS. Furthermore, the database has been updated regularly and maintained as a living program to reflect the current status. This paper presents the failure data analysis using PRinS which provides Bayesian analysis on main components in the CANDU reactor. (authors)

  11. The reliability of the Personal and Social Performance scale - informing its training and use.

    PubMed

    White, Sarah; Dominise, Christianne; Naik, Dhruv; Killaspy, Helen

    2016-09-30

    Social functioning is as an important outcome in studies of people with schizophrenia. Most measures of social function include a person's ability to manage everyday activities as well as their abilities to engage in leisure and occupational activities. The Personal Social Performance (PSP) scale assesses functioning across four dimensions (socially useful activities, personal and social relationships, self-care, disturbing and aggressive behaviours) rather than one global score and thus has been reported to be easier to use. In a pan-European study of people with severe mental illness a team of 26 researchers received training in rating the scale, after which the inter-rater reliability (IRR) was assessed and found to be not sufficiently high. A brief survey of the researchers elicited information with which to explore the low IRR and their experience of using the PSP. Clinicians were found to have higher IRR, in particular, psychologists. Patients' employment status was found to be the most important predictor of PSP. Researchers used multiple sources of information when rating the scale. Sufficient training is required to ensure IRR, particularly for non-clinical researchers, if the PSP is to be established as a reliable research tool. PMID:27428085

  12. Informed consent: what does it mean and how is it achieved?

    PubMed

    2016-05-01

    Informed consent is an essential part of any contract and, in veterinary practice, it is vital that the client understands the range of treatment options, estimated costs and the significance and risks of any procedure that a veterinary surgeon may carry out. But what does informed consent actually mean, and how is this achieved in day-to-day practice? Georgina Mills reports from a panel discussion of this topic, held during the BSAVA congress last month. PMID:27154930

  13. Evaluating Written Patient Information for Eczema in German: Comparing the Reliability of Two Instruments, DISCERN and EQIP

    PubMed Central

    McCool, Megan E.; Wahl, Josepha; Schlecht, Inga; Apfelbacher, Christian

    2015-01-01

    Patients actively seek information about how to cope with their health problems, but the quality of the information available varies. A number of instruments have been developed to assess the quality of patient information, primarily though in English. Little is known about the reliability of these instruments when applied to patient information in German. The objective of our study was to investigate and compare the reliability of two validated instruments, DISCERN and EQIP, in order to determine which of these instruments is better suited for a further study pertaining to the quality of information available to German patients with eczema. Two independent raters evaluated a random sample of 20 informational brochures in German. All the brochures addressed eczema as a disorder and/or therapy options and care. Intra-rater and inter-rater reliability were assessed by calculating intra-class correlation coefficients, agreement was tested with weighted kappas, and the correlation of the raters’ scores for each instrument was measured with Pearson’s correlation coefficient. DISCERN demonstrated substantial intra- and inter-rater reliability. It also showed slightly better agreement than EQIP. There was a strong correlation of the raters’ scores for both instruments. The findings of this study support the reliability of both DISCERN and EQIP. However, based on the results of the inter-rater reliability, agreement and correlation analyses, we consider DISCERN to be the more precise tool for our project on patient information concerning the treatment and care of eczema. PMID:26440612

  14. Writing for Understanding: The Effect of Using Informational Writing on Student Science Achievement

    ERIC Educational Resources Information Center

    Parson, Atiya

    2013-01-01

    The purpose of this quantitative study was to investigate whether or not informational writing in the science curriculum would impact fifth grade students' science achievement and conceptual understanding. The population of this study came from a metropolitan school district in the state of Georgia for school year 2012-2013. The quantitative data…

  15. Achievement, Anxiety and Self-Concept in Formal and Informal Settings.

    ERIC Educational Resources Information Center

    O'Tuel, Frances S.; Terry, Diane

    This study investigated relationships among anxiety, self-concept, achievement, sex and I.Q. in two educational settings: a structured formal setting and an open informal setting. A sample of 326 fourth grade students attending schools differing in structure and formality were given the following tests: The California Mental Aptitude Test; the…

  16. Self-Regulating Informational Text Reading Comprehension: Perceptions of Low-Achieving Students

    ERIC Educational Resources Information Center

    Mason, Linda H.; Meadan-Kaplansky, Hedda; Hedin, Laura; Taft, Raol

    2013-01-01

    Students who struggle with learning may not have the metacognition needed to support the multiple processes required to understand what is read in informational text. Instruction for these students, therefore, should include methodologies that promote self-regulation of critical thinking processes. Fifty-eight low-achieving students were provided…

  17. Students' Attitudes towards Information Technology and the Relationship with Their Academic Achievement

    ERIC Educational Resources Information Center

    Abdullah, Zhwan Dalshad; Bit Abu Ziden, Azidah; Binti Chi Aman, Rahimi; Mustafa, Khalid Ismail

    2015-01-01

    The present quantitative study aims to find out the underlying factors of attitudes towards information technology and the relationship with academic achievement among students, through a self-developed questionnaire. The attitudes of the respondents were assessed in terms of three dimensions; namely affection, behavior, and belief. The results…

  18. Technology for Educational Achievement in Wisconsin Board. Informational Paper No. 34.

    ERIC Educational Resources Information Center

    Collins, Tricia

    In an effort to address concerns in the educational community related to the use and costs of information and communications technology, the Technology for Educational Achievement in Wisconsin (TEACH) Board was created in 1997. The TEACH Board administers the distribution of grants under the technology block grant and technology training and…

  19. Key Attributes of the SAPHIRE Risk and Reliability Analysis Software for Risk-Informed Probabilistic Applications

    SciTech Connect

    Curtis Smith; James Knudsen; Kellie Kvarfordt; Ted Wood

    2008-08-01

    The Idaho National Laboratory is a primary developer of probabilistic risk and reliability analysis (PRRA) tools, dating back over 35 years. Evolving from mainframe-based software, the current state-of-the-practice has lead to the creation of the SAPHIRE software. Currently, agencies such as the Nuclear Regulatory Commission, the National Aeronautics and Aerospace Agency, the Department of Energy, and the Department of Defense use version 7 of the SAPHIRE software for many of their risk-informed activities. In order to better understand and appreciate the power of software as part of risk-informed applications, we need to recall that our current analysis methods and solution methods have built upon pioneering work done 30 to 40 years ago. We contrast this work with the current capabilities in the SAPHIRE analysis package. As part of this discussion, we provide information for both the typical features and special analysis capabilities which are available. We also present the application and results typically found with state-of-the-practice PRRA models. By providing both a high-level and detailed look at the SAPHIRE software, we give a snapshot in time for the current use of software tools in a risk-informed decision arena.

  20. Waste container weighing data processing to create reliable information of household waste generation.

    PubMed

    Korhonen, Pirjo; Kaila, Juha

    2015-05-01

    Household mixed waste container weighing data was processed by knowledge discovery and data mining techniques to create reliable information of household waste generation. The final data set included 27,865 weight measurements covering the whole year 2013 and it was selected from a database of Helsinki Region Environmental Services Authority, Finland. The data set contains mixed household waste arising in 6m(3) containers and it was processed identifying missing values and inconsistently low and high values as errors. The share of missing values and errors in the data set was 0.6%. This provides evidence that the waste weighing data gives reliable information of mixed waste generation at collection point level. Characteristic of mixed household waste arising at the waste collection point level is a wide variation between pickups. The seasonal variation pattern as a result of collective similarities in behaviour of households was clearly detected by smoothed medians of waste weight time series. The evaluation of the collection time series against the defined distribution range of pickup weights on the waste collection point level shows that 65% of the pickups were from collection points with optimally dimensioned container capacity and the collection points with over- and under-dimensioned container capacities were noted in 9.5% and 3.4% of all pickups, respectively. Occasional extra waste in containers occurred in 21.2% of the pickups indicating the irregular behaviour of individual households. The results of this analysis show that processing waste weighing data using knowledge discovery and data mining techniques provides trustworthy information of household waste generation and its variations. PMID:25765610

  1. A highly reliable, autonomous data communication subsystem for an advanced information processing system

    NASA Technical Reports Server (NTRS)

    Nagle, Gail; Masotto, Thomas; Alger, Linda

    1990-01-01

    The need to meet the stringent performance and reliability requirements of advanced avionics systems has frequently led to implementations which are tailored to a specific application and are therefore difficult to modify or extend. Furthermore, many integrated flight critical systems are input/output intensive. By using a design methodology which customizes the input/output mechanism for each new application, the cost of implementing new systems becomes prohibitively expensive. One solution to this dilemma is to design computer systems and input/output subsystems which are general purpose, but which can be easily configured to support the needs of a specific application. The Advanced Information Processing System (AIPS), currently under development has these characteristics. The design and implementation of the prototype I/O communication system for AIPS is described. AIPS addresses reliability issues related to data communications by the use of reconfigurable I/O networks. When a fault or damage event occurs, communication is restored to functioning parts of the network and the failed or damage components are isolated. Performance issues are addressed by using a parallelized computer architecture which decouples Input/Output (I/O) redundancy management and I/O processing from the computational stream of an application. The autonomous nature of the system derives from the highly automated and independent manner in which I/O transactions are conducted for the application as well as from the fact that the hardware redundancy management is entirely transparent to the application.

  2. Improving University Ranking to Achieve University Competitiveness by Management Information System

    NASA Astrophysics Data System (ADS)

    Dachyar, M.; Dewi, F.

    2015-05-01

    One way to increase university competitiveness is through information system management. A literature review was done to find information system factors that affect university performance in Quacquarelli Symonds (QS) University Ranking: Asia evaluation. Information system factors were then eliminated using Delphi method through consensus of 7 experts. Result from Delphi method was used as measured variables in PLS-SEM. Estimation with PLS-SEM method through 72 respondents shows that the latent variable academic reputation and citation per paper have significant correlation to university competitiveness. In University of Indonesia (UI) the priority to increase university competitiveness as follow: (i) network building in international conference, (ii) availability of research data to public, (iii) international conference information, (iv) information on achievements and accreditations of each major, (v) ease of employment for alumni.

  3. Accessibility and reliability of cutaneous laser surgery information on the World Wide Web.

    PubMed

    Bykowski, J L; Alora, M B; Dover, J S; Arndt, K A

    2000-05-01

    The World Wide Web has provided the public with easy and affordable access to a vast range of information. However, claims may be unsubstantiated and misleading. The purpose of this study was to use cutaneous laser surgery as a model to assess the availability and reliability of Web sites and to evaluate this resource for the quality of patient and provider education. Three commercial methods of searching the Internet were used, identifying nearly 500,000 possible sites. The first 100 sites listed by each search engine (a total of 300 sites) were compared. Of these, 126 were listed repeatedly within a given retrieval method, whereas only 3 sites were identified by all 3 search engines. After elimination of duplicates, 40 sites were evaluated for content and currency of information. The most common features included postoperative care suggestions, options for pain management or anesthesia, a description of the way in which lasers work, and the types of lasers used for different procedures. Potential contraindications to laser procedures were described on fewer than 30% of the sites reviewed. None of the sites contained substantiation of claims or referrals to peer-reviewed publications or research. Because of duplication and the prioritization systems of search engines, the ease of finding sites did not correlate with the quality of the site's content. Our findings show that advertisements for services exceed useful information. PMID:10775854

  4. Regular Deployment of Wireless Sensors to Achieve Connectivity and Information Coverage.

    PubMed

    Cheng, Wei; Li, Yong; Jiang, Yi; Yin, Xipeng

    2016-01-01

    Coverage and connectivity are two of the most critical research subjects in WSNs, while regular deterministic deployment is an important deployment strategy and results in some pattern-based lattice WSNs. Some studies of optimal regular deployment for generic values of rc/rs were shown recently. However, most of these deployments are subject to a disk sensing model, and cannot take advantage of data fusion. Meanwhile some other studies adapt detection techniques and data fusion to sensing coverage to enhance the deployment scheme. In this paper, we provide some results on optimal regular deployment patterns to achieve information coverage and connectivity as a variety of rc/rs, which are all based on data fusion by sensor collaboration, and propose a novel data fusion strategy for deployment patterns. At first the relation between variety of rc/rs and density of sensors needed to achieve information coverage and connectivity is derived in closed form for regular pattern-based lattice WSNs. Then a dual triangular pattern deployment based on our novel data fusion strategy is proposed, which can utilize collaborative data fusion more efficiently. The strip-based deployment is also extended to a new pattern to achieve information coverage and connectivity, and its characteristics are deduced in closed form. Some discussions and simulations are given to show the efficiency of all deployment patterns, including previous patterns and the proposed patterns, to help developers make more impactful WSN deployment decisions. PMID:27529246

  5. Extracting information from an ensemble of GCMs to reliably assess future global runoff change

    NASA Astrophysics Data System (ADS)

    Sperna Weiland, F. C.; van Beek, L. P. H.; Weerts, A. H.; Bierkens, M. F. P.

    2012-01-01

    SummaryFuture runoff projections derived from different global climate models (GCMs) show large differences. Therefore, within this study the, information from multiple GCMs has been combined to better assess hydrological changes. For projections of precipitation and temperature the Reliability ensemble averaging (REA) method was introduced to calculate weighted average ensemble change with an accompanying uncertainty range. In this study the original REA method is compared with three other methods that calculate runoff change by selecting or weighting GCMs on their inter-model similarity for the current and future climate. All methods are applied to distributed runoff fields calculated with the hydrological model PCR-GLOBWB forced with meteorological data from an ensemble of 12 GCMs. Differences between weighted and non-weighted average runoff changes for 2100 are small. Within a validation experiment, where GCM ensemble mean change is derived between the time-slices 1961-1975 and 1976-1990, the non-weighted ensemble change resembled observed change best. Yet, both the weighted and non-weighted average change were too conservative. This underscores the importance of considering an uncertainty range alongside the ensemble average change. In this study the uncertainty range (or 95% confidence interval) is defined by four times the root mean square difference around the ensemble mean change. The uncertainty range derived with the non-weighted method is relatively wide, upper and lower uncertainty bounds show large biases from observed change. However, the uncertainty range was reliably be reduced by using only a selection of GCMs which show high inter-model similarity for the current and future climate.

  6. HELIOS Critical Design Review: Reliability

    NASA Technical Reports Server (NTRS)

    Benoehr, H. C.; Herholz, J.; Prem, H.; Mann, D.; Reichert, L.; Rupp, W.; Campbell, D.; Boettger, H.; Zerwes, G.; Kurvin, C.

    1972-01-01

    This paper presents Helios Critical Design Review Reliability form October 16-20, 1972. The topics include: 1) Reliability Requirement; 2) Reliability Apportionment; 3) Failure Rates; 4) Reliability Assessment; 5) Reliability Block Diagram; and 5) Reliability Information Sheet.

  7. A proteomic approach for the rapid, multi-informative and reliable identification of blood.

    PubMed

    Patel, E; Cicatiello, P; Deininger, L; Clench, M R; Marino, G; Giardina, P; Langenburg, G; West, A; Marshall, P; Sears, V; Francese, S

    2016-01-01

    Blood evidence is frequently encountered at the scene of violent crimes and can provide valuable intelligence in the forensic investigation of serious offences. Because many of the current enhancement methods used by crime scene investigators are presumptive, the visualisation of blood is not always reliable nor does it bear additional information. In the work presented here, two methods employing a shotgun bottom up proteomic approach for the detection of blood are reported; the developed protocols employ both an in solution digestion method and a recently proposed procedure involving immobilization of trypsin on hydrophobin Vmh2 coated MALDI sample plate. The methods are complementary as whilst one yields more identifiable proteins (as biomolecular signatures), the other is extremely rapid (5 minutes). Additionally, data demonstrate the opportunity to discriminate blood provenance even when two different blood sources are present in a mixture. This approach is also suitable for old bloodstains which had been previously chemically enhanced, as experiments conducted on a 9-year-old bloodstain deposited on a ceramic tile demonstrate. PMID:26596622

  8. Reliability and Validity of the Clinical Dementia Rating for Community-Living Elderly Subjects without an Informant

    PubMed Central

    Nyunt, Ma Shwe Zin; Chong, Mei Sian; Lim, Wee Shiong; Lee, Tih Shih; Yap, Philip; Ng, Tze Pin

    2013-01-01

    Background The Clinical Dementia Rating (CDR) scale is widely used to assess cognitive impairment in Alzheimer's disease. It requires collateral information from a reliable informant who is not available in many instances. We adapted the original CDR scale for use with elderly subjects without an informant (CDR-NI) and evaluated its reliability and validity for assessing mild cognitive impairment (MCI) and dementia among community-dwelling elderly subjects. Method At two consecutive visits 1 week apart, nurses trained in CDR assessment interviewed, observed and rated cognitive and functional performance according to a protocol in 90 elderly subjects with suboptimal cognitive performance [Mini-Mental State Examination (MMSE) <26 and/or Montreal Cognitive Assessment (MOCA) <26] and without informants according to a protocol. CDR domains and global scores were assigned after the second visit based upon corroborative information from the subjects' responses to questions, role-play, and observed performance in specifically assigned tasks at home and within the community. Results The CDR-NI scores (0, 0.5, 1) showed good internal consistency (Crohnbach's α 0.83-0.84), inter-rater reliability (κ 0.77-1.00 for six domains and 0.95 for global rating) and test-retest reliability (κ 0.75-1.00 for six domains and 0.80 for global rating), good agreement (κ 0.79) with the clinical assessment status of MCI (n = 37) and dementia (n = 4) and significant differences in the mean scores for MMSE, MOCA and Instrumental Activities of Daily Living (ANOVA global p < 0.001). Conclusion Owing to the protocol of the interviews, assessments and structured observations gathered during the two visits, CDR-NI provides valid and reliable assessment of MCI and dementia in community-living elderly subjects without an informant. PMID:24348502

  9. Eco-label conveys reliable information on fish stock health to seafood consumers.

    PubMed

    Gutiérrez, Nicolás L; Valencia, Sarah R; Branch, Trevor A; Agnew, David J; Baum, Julia K; Bianchi, Patricia L; Cornejo-Donoso, Jorge; Costello, Christopher; Defeo, Omar; Essington, Timothy E; Hilborn, Ray; Hoggarth, Daniel D; Larsen, Ashley E; Ninnes, Chris; Sainsbury, Keith; Selden, Rebecca L; Sistla, Seeta; Smith, Anthony D M; Stern-Pirlot, Amanda; Teck, Sarah J; Thorson, James T; Williams, Nicholas E

    2012-01-01

    Concerns over fishing impacts on marine populations and ecosystems have intensified the need to improve ocean management. One increasingly popular market-based instrument for ecological stewardship is the use of certification and eco-labeling programs to highlight sustainable fisheries with low environmental impacts. The Marine Stewardship Council (MSC) is the most prominent of these programs. Despite widespread discussions about the rigor of the MSC standards, no comprehensive analysis of the performance of MSC-certified fish stocks has yet been conducted. We compared status and abundance trends of 45 certified stocks with those of 179 uncertified stocks, finding that 74% of certified fisheries were above biomass levels that would produce maximum sustainable yield, compared with only 44% of uncertified fisheries. On average, the biomass of certified stocks increased by 46% over the past 10 years, whereas uncertified fisheries increased by just 9%. As part of the MSC process, fisheries initially go through a confidential pre-assessment process. When certified fisheries are compared with those that decline to pursue full certification after pre-assessment, certified stocks had much lower mean exploitation rates (67% of the rate producing maximum sustainable yield vs. 92% for those declining to pursue certification), allowing for more sustainable harvesting and in many cases biomass rebuilding. From a consumer's point of view this means that MSC-certified seafood is 3-5 times less likely to be subject to harmful fishing than uncertified seafood. Thus, MSC-certification accurately identifies healthy fish stocks and conveys reliable information on stock status to seafood consumers. PMID:22928029

  10. Eco-Label Conveys Reliable Information on Fish Stock Health to Seafood Consumers

    PubMed Central

    Gutiérrez, Nicolás L.; Valencia, Sarah R.; Branch, Trevor A.; Agnew, David J.; Baum, Julia K.; Bianchi, Patricia L.; Cornejo-Donoso, Jorge; Costello, Christopher; Defeo, Omar; Essington, Timothy E.; Hilborn, Ray; Hoggarth, Daniel D.; Larsen, Ashley E.; Ninnes, Chris; Sainsbury, Keith; Selden, Rebecca L.; Sistla, Seeta; Smith, Anthony D. M.; Stern-Pirlot, Amanda; Teck, Sarah J.; Thorson, James T.; Williams, Nicholas E.

    2012-01-01

    Concerns over fishing impacts on marine populations and ecosystems have intensified the need to improve ocean management. One increasingly popular market-based instrument for ecological stewardship is the use of certification and eco-labeling programs to highlight sustainable fisheries with low environmental impacts. The Marine Stewardship Council (MSC) is the most prominent of these programs. Despite widespread discussions about the rigor of the MSC standards, no comprehensive analysis of the performance of MSC-certified fish stocks has yet been conducted. We compared status and abundance trends of 45 certified stocks with those of 179 uncertified stocks, finding that 74% of certified fisheries were above biomass levels that would produce maximum sustainable yield, compared with only 44% of uncertified fisheries. On average, the biomass of certified stocks increased by 46% over the past 10 years, whereas uncertified fisheries increased by just 9%. As part of the MSC process, fisheries initially go through a confidential pre-assessment process. When certified fisheries are compared with those that decline to pursue full certification after pre-assessment, certified stocks had much lower mean exploitation rates (67% of the rate producing maximum sustainable yield vs. 92% for those declining to pursue certification), allowing for more sustainable harvesting and in many cases biomass rebuilding. From a consumer’s point of view this means that MSC-certified seafood is 3–5 times less likely to be subject to harmful fishing than uncertified seafood. Thus, MSC-certification accurately identifies healthy fish stocks and conveys reliable information on stock status to seafood consumers. PMID:22928029

  11. Digital Avionics Information System (DAIS): Reliability and Maintainability Model Users Guide. Final Report, May 1975-July 1977.

    ERIC Educational Resources Information Center

    Czuchry, Andrew J.; And Others

    This report provides a complete guide to the stand alone mode operation of the reliability and maintenance (R&M) model, which was developed to facilitate the performance of design versus cost trade-offs within the digital avionics information system (DAIS) acquisition process. The features and structure of the model, its input data requirements,…

  12. Increased Reliability Of Genetic Evaluations For Dairy Cattle In The United States From Use Of Genomic Information

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of genomic information increased reliability of genetic evaluations compared to parent averages by 28.4% for Holsteins, 20.7% for Jerseys and 12.8% for Brown Swiss when averaged across milk, fat and protein yields and three functional traits. Correlations of genomic predictions based on evaluati...

  13. Reliability and Levels of Difficulty of Objective Test Items in a Mathematics Achievement Test: A Study of Ten Senior Secondary Schools in Five Local Government Areas of Akure, Ondo State

    ERIC Educational Resources Information Center

    Adebule, S. O.

    2009-01-01

    This study examined the reliability and difficult indices of Multiple Choice (MC) and True or False (TF) types of objective test items in a Mathematics Achievement Test (MAT). The instruments used were two variants- 50-items Mathematics achievement test based on the multiple choice and true or false test formats. A total of five hundred (500)…

  14. Librarians’ Role in Development and Achievement of Central Library Users’ Information Literacy (a Case Study: Iran)

    PubMed Central

    Yaminfirooz, Mousa; Siamian, Hasan; Shahrabi, Afsaneh

    2013-01-01

    Introduction: Due to the development of technologies, communications, databases and information resource varieties in today’s information age, our various social, economic, cultural and political needs cannot be fulfilled by relying merely on past knowledge and skills as done previously. Information literacy (IL) as a set of necessary skills for all of us is an effective way of treating new technologies and their effective application in our lives. The study aimed to survey the library users’ views in the Central Library of Babol University of Medical Sciences (The Library), Iran, on the role and influences of librarians on their IL development and improvement. Methods: This analytical survey used a researcher-made questionnaire for data collection. Research population consisted of all users referring Information Unit of The Library during 22 September - 20 December 2010. Of them, 150 users participating in at least 5 workshops held by The Library were selected as the study sample. Results: Based on the findings, 52.7 percent of the subjects rated the influence of the librarians on their IL development much and very much. 44.7 percent claimed that they more acquired IL skills from librarians rather than others. 100 (63.3%) subjects preferred workshops held by the librarian to other workshops. Conclusion: The users of Information Unit of The Library perceived the training IL skills by librarians as a main influencing factor in their IL development and achievement. This emphasized the necessity of teaching IL to users and training the librarians in better teaching IL skills to library user. PMID:24511265

  15. A Service Oriented Architecture Approach to Achieve Interoperability between Immunization Information Systems in Iran

    PubMed Central

    Hosseini, Masoud; Ahmadi, Maryam; Dixon, Brian E.

    2014-01-01

    Clinical decision support (CDS) systems can support vaccine forecasting and immunization reminders; however, immunization decision-making requires data from fragmented, independent systems. Interoperability and accurate data exchange between immunization information systems (IIS) is an essential factor to utilize Immunization CDS systems. Service oriented architecture (SOA) and Health Level 7 (HL7) are dominant standards for web-based exchange of clinical information. We implemented a system based on SOA and HL7 v3 to support immunization CDS in Iran. We evaluated system performance by exchanging 1500 immunization records for roughly 400 infants between two IISs. System turnaround time is less than a minute for synchronous operation calls and the retrieved immunization history of infants were always identical in different systems. CDS generated reports were accordant to immunization guidelines and the calculations for next visit times were accurate. Interoperability is rare or nonexistent between IIS. Since inter-state data exchange is rare in United States, this approach could be a good prototype to achieve interoperability of immunization information. PMID:25954452

  16. A Service Oriented Architecture Approach to Achieve Interoperability between Immunization Information Systems in Iran.

    PubMed

    Hosseini, Masoud; Ahmadi, Maryam; Dixon, Brian E

    2014-01-01

    Clinical decision support (CDS) systems can support vaccine forecasting and immunization reminders; however, immunization decision-making requires data from fragmented, independent systems. Interoperability and accurate data exchange between immunization information systems (IIS) is an essential factor to utilize Immunization CDS systems. Service oriented architecture (SOA) and Health Level 7 (HL7) are dominant standards for web-based exchange of clinical information. We implemented a system based on SOA and HL7 v3 to support immunization CDS in Iran. We evaluated system performance by exchanging 1500 immunization records for roughly 400 infants between two IISs. System turnaround time is less than a minute for synchronous operation calls and the retrieved immunization history of infants were always identical in different systems. CDS generated reports were accordant to immunization guidelines and the calculations for next visit times were accurate. Interoperability is rare or nonexistent between IIS. Since inter-state data exchange is rare in United States, this approach could be a good prototype to achieve interoperability of immunization information. PMID:25954452

  17. Using space and time to encode vibrotactile information: toward an estimate of the skin's achievable throughput.

    PubMed

    Novich, Scott D; Eagleman, David M

    2015-10-01

    Touch receptors in the skin can relay various forms of abstract information, such as words (Braille), haptic feedback (cell phones, game controllers, feedback for prosthetic control), and basic visual information such as edges and shape (sensory substitution devices). The skin can support such applications with ease: They are all low bandwidth and do not require a fine temporal acuity. But what of high-throughput applications? We use sound-to-touch conversion as a motivating example, though others abound (e.g., vision, stock market data). In the past, vibrotactile hearing aids have demonstrated improvement in speech perceptions in the deaf. However, a sound-to-touch sensory substitution device that works with high efficacy and without the aid of lipreading has yet to be developed. Is this because skin simply does not have the capacity to effectively relay high-throughput streams such as sound? Or is this because the spatial and temporal properties of skin have not been leveraged to full advantage? Here, we begin to address these questions with two experiments. First, we seek to determine the best method of relaying information through the skin using an identification task on the lower back. We find that vibrotactile patterns encoding information in both space and time yield the best overall information transfer estimate. Patterns encoded in space and time or "intensity" (the coupled coding of vibration frequency and force) both far exceed performance of only spatially encoded patterns. Next, we determine the vibrotactile two-tacton resolution on the lower back-the distance necessary for resolving two vibrotactile patterns. We find that our vibratory motors conservatively require at least 6 cm of separation to resolve two independent tactile patterns (>80 % correct), regardless of stimulus type (e.g., spatiotemporal "sweeps" versus single vibratory pulses). Six centimeter is a greater distance than the inter-motor distances used in Experiment 1 (2.5 cm), which

  18. Assembly and comparison of available solar hot water system reliability databases and information.

    SciTech Connect

    Menicucci, David F.

    2009-05-01

    Solar hot water (SHW) systems have been installed commercially for over 30 years, yet few quantitative details are known about their reliability. This report describes a comprehensive analysis of all of the known major previous research and data regarding the reliability of SHW systems and components. Some important conclusions emerged. First, based on a detailed inspection of ten-year-old systems in Florida, about half of active systems can be expected to fail within a ten-year period. Second, valves were identified as the probable cause of a majority of active SHW failures. Third, passive integral and thermosiphon SHW systems have much lower failure rates than active ones, probably due to their simple design that employs few mechanical parts. Fourth, it is probable that the existing data about reliability do not reveal the full extent of fielded system failures because most of the data were based on trouble calls. Often an SHW system owner is not aware of a failure because the backup system silently continues to produce hot water. Thus, a repair event may not be generated in a timely manner, if at all. This final report for the project provides all of the pertinent details about this study, including the source of the data, the techniques to assure their quality before analysis, the organization of the data into perhaps the most comprehensive reliability database in existence, a detailed statistical analysis, and a list of recommendations for additional critical work. Important recommendations include the inclusion of an alarm on SHW systems to identify a failed system, the need for a scientifically designed study to collect high-quality reliability data that will lead to design improvements and lower costs, and accelerated testing of components that are identified as highly problematic.

  19. [Experimental studies of reliability of symbolic information perception from the aviation LCD panel].

    PubMed

    Ivanov, A I; Lapa, V V; Davydov, V V; Riabinin, V A; Golosov, S Iu

    2014-01-01

    Results of tachistiscopic experiments on reliability of symbol recognition on LCD panel as a function of screen definition (640 x 480, 800 x 600 and 1024 x 768 pixels), angular size of a picture element (10, 15, 20 and 30 angular min) and luminance contrast (LC) with the background (0.2 to 1.4 standard units) are presented. The obtained quantitative relations indicate significance of the above parameters for recognition reliability. Symbols with the size of 30 angular min and LC of 0.5 were recognizable irrespective of screen definition in the study. Recognition of symbols 20 and 15 angular min of size was much dependent on screen definition and LC of symbols. For symbols of size 10 angular min and LC ≥ 1.0 the recognition probability did not exceed 0.59-0.7. PMID:25365875

  20. Support evidence statistics for operation reliability assessment using running state information and its application to rolling bearing

    NASA Astrophysics Data System (ADS)

    Xiao, Wenrong; Cheng, Wei; Zi, Yanyang; Zhao, Chenlu; Sun, Chuang; Liu, Zhiwen; Chen, Jinglong; He, Zhengjia

    2015-08-01

    Traditional reliability evaluation method generally requires a large amount of previous data and information on historical lifetime. For an individual mechanical device without historical lifetime data, it is difficult to carry out the reliability assessment by using the traditional method. To attempt exploring this difficult problem, support evidence statistics (SES) as an approach to operation reliability assessment is presented in this paper. Moreover, this presented method is also expected to indicate the physical state changes of the individual mechanical device. Since in scientific research, evidence usually goes towards supporting or rejecting a hypothesis. For a running device, evidences derived from the running state information should consistently demonstrate its current sole-running-state within a given short time interval. In practice, due to the interference of environmental noises, these evidences lose the consistency. Accordingly, they can be classified into two classes: the firm evidences and the flimsy evidences. Analogous to the support vector data description (SVDD), these firm evidences which show remarkable consistency can form a support evidence space (SESP) through one-class classification. Suppose that a SESP is obtained by using the evidences accumulated from the normal running state, the device operation reliability at any time of unknown running state can be evaluated through the statistical comparison between the normal SESP and the unknown SESP. This reliability evaluation process is named as SES. The most fundamental distinction between the proposed method and the traditional method lies in different statistical objects. The traditional methods are to analyze lifetime data while the proposed methods are to analyze running state data. Obviously, the evidence feature optimization plays a crucial role in the presented method. The maximum correlation and minimum redundancy (MCMR) method is improved by principal component analysis (PCA) to

  1. Parsing the Achievement Gap: Baselines for Tracking Progress. Policy Information Report.

    ERIC Educational Resources Information Center

    Barton, Paul E.

    The gaps in school achievement among racial and ethnic groups and between students from poor and nonpoor families are well documented. They are large, and have been persistent. This publication is about conditions that help create and perpetuate achievement gaps. It focuses on the many antecedents of differences in school achievement college-going…

  2. Achievable information rates calculation for optical OFDM few-mode fiber long-haul transmission systems.

    PubMed

    Lin, Changyu; Djordjevic, Ivan B; Zou, Ding

    2015-06-29

    We propose a method to estimate the lower bound of achievable information rates (AIRs) of high speed orthogonal frequency-division multiplexing (OFDM) in spatial division multiplexing (SDM) optical long-haul transmission systems. The estimation of AIR is based on the forward recursion of multidimensional super-symbol efficient sliding-window Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm. We consider most of the degradations of fiber links including nonlinear effects in few-mode fiber (FMF). This method does not consider the SDM as a simple multiplexer of independent data streams, but provides a super-symbol version for AIR calculation over spatial channels. This super-symbol version of AIR calculation algorithm, in principle, can be used for arbitrary multiple-input-multiple-output (MIMO)-SDM system with channel memory consideration. We illustrate this method by performing Monte Carlo simulations in a complete FMF model. Both channel model and algorithm for calculation of the AIRs are described in details. We also compare the AIRs results for QPSK/16QAM in both single mode fiber (SMF)- and FMF-based optical OFDM transmission. PMID:26191696

  3. An Information Comparison of Conventional and Adaptive Tests in the Measurement of Classroom Achievement. Research Report 77-7.

    ERIC Educational Resources Information Center

    Bejar, Isaac I.; And Others

    Information provided by typical and improved conventional classroom achievement tests was compared with information provided by an adaptive test covering the same subject matter. Both tests were administered to over 700 college students in a general biology course. Using the same scoring method, adaptive testing was found to yield substantially…

  4. Effects of perceived reliability and generalization of crime-related information on detection in the concealed information test.

    PubMed

    Elaad, Eitan

    2010-03-01

    The accuracy of the Concealed Information Test (CIT) in detecting information concealed by informed innocent participants was assessed under varying levels of probability that the obtained information is related to the crime and is therefore correct. For this purpose, 64 participants were randomly assigned to four experimental conditions that were formed by probability levels that the gathered information is correct and is related to the crime. Either absolutely correct (100% correct), highly correct (80%, correct), highly incorrect (20% correct) or totally incorrect (0%, correct) conditions were created. Response generalization was manipulated by replacing 3 of 6 correct items with related stimuli. The replaced stimuli were related to the correct items either semantically, phonetically, or numerically. Informed innocent participants showed larger electrodermal responses to items with a higher probability of being correct. It was further found that participants elicited stronger responses to correct than to replaced items. Theoretical and practical implications of the present results are discussed. PMID:20093151

  5. Trust in Testimony about Strangers: Young Children Prefer Reliable Informants Who Make Positive Attributions

    ERIC Educational Resources Information Center

    Boseovski, Janet J.

    2012-01-01

    Young children have been described as critical consumers of information, particularly in the domain of language learning. Indeed, children are more likely to learn novel words from people with accurate histories of object labeling than with inaccurate ones. But what happens when informant testimony conflicts with a tendency to see the world in a…

  6. Reliable and robust transmission and storage techniques for medical images with patient information.

    PubMed

    Nergui, Myagmarbayar; Acharya, U Sripati; Acharya U, Rajendra; Yu, Wenwei

    2010-12-01

    There is an increased emphasis on the use of digital techniques in all aspects of human life today. Broadcast radio and television, cellular phone services, consumer and entertainment electronics etc are increasingly using digital signal processing techniques to improve the quality of service. Transmission and storage of documentation and images pertaining to patient records cannot remain an exception to this global trend. Hence, patient records (text and image information) are increasingly stored and processed in digital form. Currently, text and image information, which constitute two separate pieces of data are handled as different files. Thus, there is a possibility of the text and message information, pertaining to different patients, being interchanged and thus mishandled. This can be avoided by merging text and image information in such a manner that the two can be separated without perceptible damage to information contained in either file. Digital watermarking techniques can be used to interleave patient information with medical images. In this work, we have employed digital watermarking along with strong cryptographic protocols and powerful error correcting codes. This reduces the probability of sensitive patient information falling into the wrong hands and ensures information integrity when it is conveyed over noisy channels. PMID:20703594

  7. The Development of Dynamic Human Reliability Analysis Simulations for Inclusion in Risk Informed Safety Margin Characterization Frameworks

    SciTech Connect

    Jeffrey C. Joe; Diego Mandelli; Ronald L. Boring; Curtis L. Smith; Rachel B. Shirley

    2015-07-01

    The United States Department of Energy is sponsoring the Light Water Reactor Sustainability program, which has the overall objective of supporting the near-term and the extended operation of commercial nuclear power plants. One key research and development (R&D) area in this program is the Risk-Informed Safety Margin Characterization pathway, which combines probabilistic risk simulation with thermohydraulic simulation codes to define and manage safety margins. The R&D efforts to date, however, have not included robust simulations of human operators, and how the reliability of human performance or lack thereof (i.e., human errors) can affect risk-margins and plant performance. This paper describes current and planned research efforts to address the absence of robust human reliability simulations and thereby increase the fidelity of simulated accident scenarios.

  8. Accuracy and reliability of Chile's National Air Quality Information System for measuring particulate matter: Beta attenuation monitoring issue.

    PubMed

    Toro A, Richard; Campos, Claudia; Molina, Carolina; Morales S, Raul G E; Leiva-Guzmán, Manuel A

    2015-09-01

    A critical analysis of Chile's National Air Quality Information System (NAQIS) is presented, focusing on particulate matter (PM) measurement. This paper examines the complexity, availability and reliability of monitoring station information, the implementation of control systems, the quality assurance protocols of the monitoring station data and the reliability of the measurement systems in areas highly polluted by particulate matter. From information available on the NAQIS website, it is possible to confirm that the PM2.5 (PM10) data available on the site correspond to 30.8% (69.2%) of the total information available from the monitoring stations. There is a lack of information regarding the measurement systems used to quantify air pollutants, most of the available data registers contain gaps, almost all of the information is categorized as "preliminary information" and neither standard operating procedures (operational and validation) nor assurance audits or quality control of the measurements are reported. In contrast, events that cause saturation of the monitoring detectors located in northern and southern Chile have been observed using beta attenuation monitoring. In these cases, it can only be concluded that the PM content is equal to or greater than the saturation concentration registered by the monitors and that the air quality indexes obtained from these measurements are underestimated. This occurrence has been observed in 12 (20) public and private stations where PM2.5 (PM10) is measured. The shortcomings of the NAQIS data have important repercussions for the conclusions obtained from the data and for how the data are used. However, these issues represent opportunities for improving the system to widen its use, incorporate comparison protocols between equipment, install new stations and standardize the control system and quality assurance. PMID:25796098

  9. The Information Edge: Using Data to Accelerate Achievement--Technology Counts, 2006

    ERIC Educational Resources Information Center

    Edwards, Virginia, Ed.

    2006-01-01

    This special issue presents the ninth edition of "Education Week's" annual report on education technology, "Technology Counts." The annual report found that the nation has made dramatic progress in developing computerized data systems that can reliably guide education decision-making, but still has plenty of work to do before those systems can…

  10. Reliability of neuronal information conveyed by unreliable neuristor-based leaky integrate-and-fire neurons: a model study

    PubMed Central

    Lim, Hyungkwang; Kornijcuk, Vladimir; Seok, Jun Yeong; Kim, Seong Keun; Kim, Inho; Hwang, Cheol Seong; Jeong, Doo Seok

    2015-01-01

    We conducted simulations on the neuronal behavior of neuristor-based leaky integrate-and-fire (NLIF) neurons. The phase-plane analysis on the NLIF neuron highlights its spiking dynamics – determined by two nullclines conditional on the variables on the plane. Particular emphasis was placed on the operational noise arising from the variability of the threshold switching behavior in the neuron on each switching event. As a consequence, we found that the NLIF neuron exhibits a Poisson-like noise in spiking, delimiting the reliability of the information conveyed by individual NLIF neurons. To highlight neuronal information coding at a higher level, a population of noisy NLIF neurons was analyzed in regard to probability of successful information decoding given the Poisson-like noise of each neuron. The result demonstrates highly probable success in decoding in spite of large variability – due to the variability of the threshold switching behavior – of individual neurons. PMID:25966658

  11. Achievement Information Monitoring in Schools (AIMS): Larger Straws in the Winds of Change. Professional Paper 36.

    ERIC Educational Resources Information Center

    Follettie, Joseph F.

    The Southwest Regional Laboratory for Educational Research and Development (SWRL) is dedicated to the belief that individual differences among students do not stand in the way of universal quality instructional achievement in the nation's schools. Important steps towards the condition of universal instructionalized achievement are: (1) the…

  12. Turning State Data and Research into Information: An Example from Washington State's Student Achievement Initiative

    ERIC Educational Resources Information Center

    Prince, David; Seppanen, Loretta; Stephens, Deborah; Stewart, Carmen

    2010-01-01

    This chapter discusses Washington State's Student Achievement Initiative, a new performance funding system for community and technical colleges. Its purposes are to improve public accountability by more accurately describing what students achieve from enrolling in state colleges each year and provide incentives through financial rewards to…

  13. Is the internet a reliable source of information for patients seeking total ankle replacement?

    PubMed

    Elliott, Andrew D; Bartel, Annette F P; Simonson, Devin; Roukis, Thomas S

    2015-01-01

    The modern patient population relies on the Internet to provide knowledge about medical procedures. However, a gap between established medical guidelines and the information provided on the Internet exists. Because of the general poor quality of the medical information available on the Internet and the increasing popularity of total ankle replacement (TAR) with its known potential serious complications, we undertook the present study to evaluate the information on TAR available to the general public through the Internet and to determine the quality of information according to authorship type and site certification status. Three common search engines were used to identify a total of 105 websites. The TAR information quality was rated as "excellent," "high," "moderate," "low," or "unacceptable." The sites were evaluated for authorship or sponsorship, content, and other criteria. The data were analyzed as a complete set, as a comparison among authorship types (academic, private, industry, or other), and by certification status. Websites with scores of excellent or high were 35% of the sites reviewed, and 48% were ranked as poor or unacceptable. Of the authorship types, the highest quality authorship was for the industry and other sites, which rated high or excellent 46% of the time. Eight percent of the sites evaluated were certified; however, certification status was not associated with improved information quality. Our study has demonstrated a low quality of TAR information available across all website types, regardless of authorship type. We suggest a partnership between professional organizations and physicians to ensure that provider websites reflect the current indications and contraindications of TAR to enhance patient education. PMID:25746768

  14. Tracking the Reliability of the U.S. Electric Power System: An Assessment of Publicly Available Information Reported to State Public Utility Commissions

    SciTech Connect

    LaCommare, Kristina H.; Eto, Joseph H.

    2008-10-10

    Large blackouts, such as the August 14-15, 2003 blackout in the northeasternUnited States and Canada, focus attention on the importance of reliable electric service. As public and private efforts are undertaken to improve reliability and prevent power interruptions, it is appropriate to assess their effectiveness. Measures of reliability, such as the frequency and duration of power interruptions, have been reported by electric utilities to state public utility commissions for many years. This study examines current state and utility practices for collecting and reporting electricity reliability information and discusses challenges that arise in assessing reliability because of differences among these practices. The study is based primarily on reliability information for 2006 reported by 123 utilities to 37 state public utility commissions.

  15. Treatment of Passive Component Reliability in Risk-Informed Safety Margin Characterization FY 2010 Report

    SciTech Connect

    Robert W Youngblood

    2010-09-01

    The Risk-Informed Safety Margin Characterization (RISMC) pathway is a set of activities defined under the U.S. Department of Energy (DOE) Light Water Reactor Sustainability Program. The overarching objective of RISMC is to support plant life-extension decision-making by providing a state-of-knowledge characterization of safety margins in key systems, structures, and components (SSCs). A technical challenge at the core of this effort is to establish the conceptual and technical feasibility of analyzing safety margin in a risk-informed way, which, unlike conventionally defined deterministic margin analysis, is founded on probabilistic characterizations of SSC performance.

  16. A Study on Information Technology Integrated Guided Iscovery Instruction towards Students' Learning Achievement and Learning Retention

    ERIC Educational Resources Information Center

    Shieh, Chich-Jen; Yu, Lean

    2016-01-01

    In the information explosion era with constant changes of information, educators have promoted various effective learning strategies for students adapting to the complex modern society. The impact and influence of traditional teaching method have information technology integrated modern instruction and science concept learning play an important…

  17. The Reliability and Validity of the Mathematics Self-Efficacy Informative Sources Scale

    ERIC Educational Resources Information Center

    Ozyurek, Ragip

    2010-01-01

    This study focused on the convergent and discriminate validity of the Mathematics Self- Efficacy Informative Sources Scale for high school students. A total number of 692 high school students participated in the study. Both explanatory and confirmatory factor analyses were conducted for the content of the scale. Whether the Mathematics…

  18. Microcomputers: Means to Achievement. Using Information More Efficiently for Special Needs Learners.

    ERIC Educational Resources Information Center

    Brown, James M.

    1984-01-01

    Discusses database management systems for special needs student information management. Considers data access policies, implementation, software selection criteria, and special needs related uses. (SK)

  19. Field-Induced Crystalline-to-Amorphous Phase Transformation on the Si Nano-Apex and the Achieving of Highly Reliable Si Nano-Cathodes.

    PubMed

    Huang, Yifeng; Deng, Zexiang; Wang, Weiliang; Liang, Chaolun; She, Juncong; Deng, Shaozhi; Xu, Ningsheng

    2015-01-01

    Nano-scale vacuum channel transistors possess merits of higher cutoff frequency and greater gain power as compared with the conventional solid-state transistors. The improvement in cathode reliability is one of the major challenges to obtain high performance vacuum channel transistors. We report the experimental findings and the physical insight into the field induced crystalline-to-amorphous phase transformation on the surface of the Si nano-cathode. The crystalline Si tip apex deformed to amorphous structure at a low macroscopic field (0.6~1.65 V/nm) with an ultra-low emission current (1~10 pA). First-principle calculation suggests that the strong electrostatic force exerting on the electrons in the surface lattices would take the account for the field-induced atomic migration that result in an amorphization. The arsenic-dopant in the Si surface lattice would increase the inner stress as well as the electron density, leading to a lower amorphization field. Highly reliable Si nano-cathodes were obtained by employing diamond like carbon coating to enhance the electron emission and thus decrease the surface charge accumulation. The findings are crucial for developing highly reliable Si-based nano-scale vacuum channel transistors and have the significance for future Si nano-electronic devices with narrow separation. PMID:25994377

  20. Field-Induced Crystalline-to-Amorphous Phase Transformation on the Si Nano-Apex and the Achieving of Highly Reliable Si Nano-Cathodes

    NASA Astrophysics Data System (ADS)

    Huang, Yifeng; Deng, Zexiang; Wang, Weiliang; Liang, Chaolun; She, Juncong; Deng, Shaozhi; Xu, Ningsheng

    2015-05-01

    Nano-scale vacuum channel transistors possess merits of higher cutoff frequency and greater gain power as compared with the conventional solid-state transistors. The improvement in cathode reliability is one of the major challenges to obtain high performance vacuum channel transistors. We report the experimental findings and the physical insight into the field induced crystalline-to-amorphous phase transformation on the surface of the Si nano-cathode. The crystalline Si tip apex deformed to amorphous structure at a low macroscopic field (0.6~1.65 V/nm) with an ultra-low emission current (1~10 pA). First-principle calculation suggests that the strong electrostatic force exerting on the electrons in the surface lattices would take the account for the field-induced atomic migration that result in an amorphization. The arsenic-dopant in the Si surface lattice would increase the inner stress as well as the electron density, leading to a lower amorphization field. Highly reliable Si nano-cathodes were obtained by employing diamond like carbon coating to enhance the electron emission and thus decrease the surface charge accumulation. The findings are crucial for developing highly reliable Si-based nano-scale vacuum channel transistors and have the significance for future Si nano-electronic devices with narrow separation.

  1. Field-Induced Crystalline-to-Amorphous Phase Transformation on the Si Nano-Apex and the Achieving of Highly Reliable Si Nano-Cathodes

    PubMed Central

    Huang, Yifeng; Deng, Zexiang; Wang, Weiliang; Liang, Chaolun; She, Juncong; Deng, Shaozhi; Xu, Ningsheng

    2015-01-01

    Nano-scale vacuum channel transistors possess merits of higher cutoff frequency and greater gain power as compared with the conventional solid-state transistors. The improvement in cathode reliability is one of the major challenges to obtain high performance vacuum channel transistors. We report the experimental findings and the physical insight into the field induced crystalline-to-amorphous phase transformation on the surface of the Si nano-cathode. The crystalline Si tip apex deformed to amorphous structure at a low macroscopic field (0.6~1.65 V/nm) with an ultra-low emission current (1~10 pA). First-principle calculation suggests that the strong electrostatic force exerting on the electrons in the surface lattices would take the account for the field-induced atomic migration that result in an amorphization. The arsenic-dopant in the Si surface lattice would increase the inner stress as well as the electron density, leading to a lower amorphization field. Highly reliable Si nano-cathodes were obtained by employing diamond like carbon coating to enhance the electron emission and thus decrease the surface charge accumulation. The findings are crucial for developing highly reliable Si-based nano-scale vacuum channel transistors and have the significance for future Si nano-electronic devices with narrow separation. PMID:25994377

  2. Diverse Data Sets Can Yield Reliable Information through Mechanistic Modeling: Salicylic Acid Clearance

    PubMed Central

    Raymond, G. M.; Bassingthwaighte, J. B.

    2016-01-01

    This is a practical example of a powerful research strategy: putting together data from studies covering a diversity of conditions can yield a scientifically sound grasp of the phenomenon when the individual observations failed to provide definitive understanding. The rationale is that defining a realistic, quantitative, explanatory hypothesis for the whole set of studies, brings about a “consilience” of the often competing hypotheses considered for individual data sets. An internally consistent conjecture linking multiple data sets simultaneously provides stronger evidence on the characteristics of a system than does analysis of individual data sets limited to narrow ranges of conditions. Our example examines three very different data sets on the clearance of salicylic acid from humans: a high concentration set from aspirin overdoses; a set with medium concentrations from a research study on the influences of the route of administration and of sex on the clearance kinetics, and a set on low dose aspirin for cardiovascular health. Three models were tested: (1) a first order reaction, (2) a Michaelis-Menten (M-M) approach, and (3) an enzyme kinetic model with forward and backward reactions. The reaction rates found from model 1 were distinctly different for the three data sets, having no commonality. The M-M model 2 fitted each of the three data sets but gave a reliable estimates of the Michaelis constant only for the medium level data (Km = 24±5.4 mg/L); analyzing the three data sets together with model 2 gave Km = 18±2.6 mg/L. (Estimating parameters using larger numbers of data points in an optimization increases the degrees of freedom, constraining the range of the estimates). Using the enzyme kinetic model (3) increased the number of free parameters but nevertheless improved the goodness of fit to the combined data sets, giving tighter constraints, and a lower estimated Km = 14.6±2.9 mg/L, demonstrating that fitting diverse data sets with a single model

  3. Reliable structural information from multiscale decomposition with the Mellor-Brady filter

    NASA Astrophysics Data System (ADS)

    Szilágyi, Tünde; Brady, Michael

    2009-08-01

    Image-based medical diagnosis typically relies on the (poorly reproducible) subjective classification of textures in order to differentiate between diseased and healthy pathology. Clinicians claim that significant benefits would arise from quantitative measures to inform clinical decision making. The first step in generating such measures is to extract local image descriptors - from noise corrupted and often spatially and temporally coarse resolution medical signals - that are invariant to illumination, translation, scale and rotation of the features. The Dual-Tree Complex Wavelet Transform (DT-CWT) provides a wavelet multiresolution analysis (WMRA) tool e.g. in 2D with good properties, but has limited rotational selectivity. Also, it requires computationally-intensive steering due to the inherently 1D operations performed. The monogenic signal, which is defined in n >= 2D with the Riesz transform gives excellent orientation information without the need for steering. Recent work has suggested the Monogenic Riesz-Laplace wavelet transform as a possible tool for integrating these two concepts into a coherent mathematical framework. We have found that the proposed construction suffers from a lack of rotational invariance and is not optimal for retrieving local image descriptors. In this paper we show: 1. Local frequency and local phase from the monogenic signal are not equivalent, especially in the phase congruency model of a "feature", and so they are not interchangeable for medical image applications. 2. The accuracy of local phase computation may be improved by estimating the denoising parameters while maximizing a new measure of "featureness".

  4. How Need for Cognition Affects the Processing of Achievement-Related Information

    ERIC Educational Resources Information Center

    Dickhauser, Oliver; Reinhard, Marc-Andre; Diener, Claudia; Bertrams, Alex

    2009-01-01

    The present article analyzed, how need for cognition (NFC) influences the formation of performance expectancies. When processing information, individuals with lower NFC often rely on salient information and shortcuts compared to individuals higher in NFC. We assume that these preferences of processing will also make individuals low in NFC more…

  5. Identifying Predictors of Achievement in the Newly Defined Information Literacy: A Neural Network Analysis

    ERIC Educational Resources Information Center

    Sexton, Randall; Hignite, Michael; Margavio, Thomas M.; Margavio, Geanie W.

    2009-01-01

    Information Literacy is a concept that evolved as a result of efforts to move technology-based instructional and research efforts beyond the concepts previously associated with "computer literacy." While computer literacy was largely a topic devoted to knowledge of hardware and software, information literacy is concerned with students' abilities…

  6. A Review of Large-Scale "How Much Information?" Inventories: Variations, Achievements and Challenges

    ERIC Educational Resources Information Center

    Hilbert, Martin

    2015-01-01

    Introduction: Pressed by the increasing social importance of digital information, including the current attention given to the "big data paradigm", several research projects have taken up the challenge to quantify the amount of technologically mediated information. Method: This meta-study reviews the eight most important inventories in a…

  7. Information Seeking and Achievement Motivation in Middle Childhood and Adolescence: The Role of Conceptions of Ability.

    ERIC Educational Resources Information Center

    Butler, Ruth

    1999-01-01

    Examined effect of age and conceptions of ability on information seeking, performance, and motivation among middle graders. Found that students who had acquired the concept of ability responded to the task condition with strivings to learn and requests for information relevant to acquiring mastery, and to the ego condition with strivings to…

  8. Informal Learning: Student Achievement and Motivation in Science through Museum-Based Learning

    ERIC Educational Resources Information Center

    Holmes, Julie A.

    2011-01-01

    This study examined changes in student motivation and achievement in science during a visit to a university children's science museum. The study was based on the pretest-posttest control comparison group design with four treatment groups: control, exhibit, lesson and exhibit/lesson. The sample consisted of 228 sixth-grade students from a Louisiana…

  9. The Effect of Poverty on Student Achievement. Information Capsule. Volume 0901

    ERIC Educational Resources Information Center

    Blazer, Christie

    2009-01-01

    There is a strong relationship between students' socioeconomic status and their levels of academic achievement. Although educators should be held accountable for improving the performance of all students, including those living in poverty, schools alone can't eliminate the negative factors associated with poverty that lead to a large…

  10. Robotics as Means to Increase Achievement Scores in an Informal Learning Environment

    ERIC Educational Resources Information Center

    Barker, Bradley S.; Ansorge, John

    2007-01-01

    This paper reports on a pilot study that examined the use of a science and technology curriculum based on robotics to increase the achievement scores of youth ages 9-11 in an after school program. The study examined and compared the pretest and posttest scores of youth in the robotics intervention with youth in a control group. The results…

  11. National Board Certification: Impact on Student Achievement and Teacher Practices. Information Capsule. Volume 0917

    ERIC Educational Resources Information Center

    Blazer, Christie

    2010-01-01

    The combination of difficult economic times and increased accountability has led policymakers to call for evidence that students taught by National Board of Professional Teaching Standards (NBPTS)-certified teachers make greater achievement gains than those taught by non-NBPTS-certified teachers. Overall, studies show mixed results regarding the…

  12. Information and Communication Technology (ICT) Usage and Achievement of Turkish Students in Pisa 2006

    ERIC Educational Resources Information Center

    Aypay, Ahmet

    2010-01-01

    The purpose of this study is to examine the ICT usage and academic achievement of Turkish students in PISA 2006 data. The sample of the study included 4942 students from 160 schools. Frequencies, independent samples t-tests, ANOVAs, pearson correlation coefficients, exploratory factor analysis, and regression analysis were used. A high percentage…

  13. School Climate, Peer Victimization, and Academic Achievement: Results from a Multi-Informant Study

    ERIC Educational Resources Information Center

    Wang, Weijun; Vaillancourt, Tracy; Brittain, Heather L.; McDougall, Patricia; Krygsman, Amanda; Smith, David; Cunningham, Charles E.; Haltigan, J. D.; Hymel, Shelley

    2014-01-01

    School-level school climate was examined in relation to self-reported peer victimization and teacher-rated academic achievement (grade point average; GPA). Participants included a sample of 1,023 fifth-grade children nested within 50 schools. Associations between peer victimization, school climate, and GPA were examined using multilevel modeling,…

  14. Measuring Inequality of Opportunity in Education by Combining Information on Coverage and Achievement in PISA

    ERIC Educational Resources Information Center

    Gamboa, Luis Fernando; Waltenberg, Fábio D.

    2015-01-01

    Measuring the distance between countries and the goal of equality of opportunity in education has been the focus of recent contributions in the economic literature, which have concentrated either on intergroup gaps in access to a given level of studies or on intergroup gaps in educational achievement. We argue that both aspects are important and…

  15. Reliable transformation system for Microbotryum lychnidis-dioicae informed by genome and transcriptome project.

    PubMed

    Toh, Su San; Treves, David S; Barati, Michelle T; Perlin, Michael H

    2016-10-01

    Microbotryum lychnidis-dioicae is a member of a species complex infecting host plants in the Caryophyllaceae. It is used as a model system in many areas of research, but attempts to make this organism tractable for reverse genetic approaches have not been fruitful. Here, we exploited the recently obtained genome sequence and transcriptome analysis to inform our design of constructs for use in Agrobacterium-mediated transformation techniques currently available for other fungi. Reproducible transformation was demonstrated at the genomic, transcriptional and functional levels. Moreover, these initial proof-of-principle experiments provide evidence that supports the findings from initial global transcriptome analysis regarding expression from the respective promoters under different growth conditions of the fungus. The technique thus provides for the first time the ability to stably introduce transgenes and over-express target M. lychnidis-dioicae genes. PMID:27215216

  16. How reliable is online diffusion of medical information targeting patients and families?

    PubMed Central

    Xavier-Elsas, Pedro; Bastos, Sandra Epifânio; Gaspar-Elsas, Maria Ignez C

    2015-01-01

    AIM: To determine whether online diffusion of the “Ten Warning Signs of Primary Immunodeficiency Diseases (PID)’’ adheres to accepted scientific standards. METHODS: We analyzed how reproducible is online diffusion of a unique instrument, the “Ten Warning Signs of PID”, created by the Jeffrey Modell Foundation (JMF), by Google-assisted searches among highly visited sites from professional, academic and scientific organizations; governmental agencies; and patient support/advocacy organizations. We examined the diffusion, consistency of use and adequate referencing of this instrument. Where applicable, variant versions of the instrument were examined for changes in factual content that would have practical impact on physicians or on patients and their families. RESULTS: Among the first 100 sites identified by Google search, 85 faithfully reproduced the JMF model, and correctly referenced to its source. By contrast, the other 15 also referenced the JMF source but presented one or more changes in content relative to their purported model and therefore represent uncontrolled variants, of unknown origin. Discrepancies identified in the latter included changes in factual content of the original JMF list (C), as well as removal (R) and introduction (I) of novel signs (Table 2), all made without reference to any scientific publications that might account for the drastic changes in factual content. Factual changes include changes in the number of infectious episodes considered necessary to raise suspicion of PID, as well as the inclusion of various medical conditions not mentioned in the original. Together, these changes will affect the way physicians use the instrument to consult or to inform patients, and the way patients and families think about the need for specialist consultation in view of a possible PID diagnosis. CONCLUSION: The retrieved adaptations and variants, which significantly depart from the original instrument, raise concerns about standards for

  17. Validity and reliability of the Caregiver Reaction Assessment scale among primary informal caregivers for older persons in Singapore.

    PubMed

    Malhotra, Rahul; Chan, Angelique; Malhotra, Chetna; Østbye, Truls

    2012-01-01

    Previous studies evaluating the validity and reliability of the Caregiver Reaction Assessment (CRA) scale (24 items; five subscales: schedule, health, finances, family support, and esteem) in different countries are not fully congruent. This article assesses the validity and reliability of the CRA among informal caregivers of older persons in Singapore. Data from a national survey of 1190 primary informal caregivers of Singaporeans aged ≥75 years with ≥1 activity of daily living limitation was analyzed. Fit of the five-factor model was tested in half of the sample using confirmatory factor analysis (CFA) and the other half subjected to exploratory factor analysis (EFA). The CRA was modified accordingly and again subjected to CFA. The CRA's measurement equivalence/invariance (ME/I) across language of administration (Chinese/English/Malay) was assessed. CFA showed a poor fit for the five-factor model. EFA suggested the presence of four factors, three items to have neither sufficient nor unique factor loadings and items on two of the subscales to load on a single factor. CFA of the 'modified' CRA (21 items; four subscales: schedule and health, finances, family support, and esteem) suggested a better fit for the four-factor model than for the five-factor model. ME/I analysis supported partial invariance of the CRA across language of administration. The CRA scale should be assessed for relevance in Asian settings. With the suggested modifications, it is suitable for assessing negative and positive effects of caregiving among informal caregivers of older persons with activity limitations in Singapore. PMID:22838393

  18. PLME as a Cognitive Tool for Knowledge Achievement and Informal Learning

    NASA Astrophysics Data System (ADS)

    Nelkner, Tobias; Magenheim, Johannes; Reinhardt, Wolfgang

    Since 2003 the research on Personal Learning Environments has increased. These environments support problem based, situated and informal learning in social networks within organisations and educational institutions and in subject related communities. The EU project MATURE [1] enhanced this idea with the concept of a Personal Learning and Maturing Environment (PLME), which shall support and foster learning and knowledge maturing. In this paper, we present a model that describes the maturing of knowledge and informal learning. Based on an example of changing a university study course, we present the personal, community and organisational perspective on knowledge maturing and informal learning. This leads to a derivation of requirements for a PLME implementation.

  19. Challenges to Achieving Sustainable Sanitation in Informal Settlements of Kigali, Rwanda

    PubMed Central

    Tsinda, Aime; Abbott, Pamela; Pedley, Steve; Charles, Katrina; Adogo, Jane; Okurut, Kenan; Chenoweth, Jonathan

    2013-01-01

    Like most cities in developing countries, Kigali is experiencing rapid urbanisation leading to an increase in the urban population and rapid growth in the size and number of informal settlements. More than 60% of the city’s population resides in these settlements, where they experience inadequate and poor quality urban services including sanitation. This article discusses the issues and constraints related to the provision of sustainable sanitation in the informal settlements in Kigali. Two informal settlements (Gatsata and Kimisagara) were selected for the study, which used a mixed method approach for data collection. The research found that residents experienced multiple problems because of poor sanitation and that the main barrier to improved sanitation was cost. Findings from this study can be used by the city authorities in the planning of effective sanitation intervention strategies for communities in informal settlements. PMID:24336021

  20. Reliability of directional information in unsorted spikes and local field potentials recorded in human motor cortex

    NASA Astrophysics Data System (ADS)

    Perge, János A.; Zhang, Shaomin; Malik, Wasim Q.; Homer, Mark L.; Cash, Sydney; Friehs, Gerhard; Eskandar, Emad N.; Donoghue, John P.; Hochberg, Leigh R.

    2014-08-01

    Objective. Action potentials and local field potentials (LFPs) recorded in primary motor cortex contain information about the direction of movement. LFPs are assumed to be more robust to signal instabilities than action potentials, which makes LFPs, along with action potentials, a promising signal source for brain-computer interface applications. Still, relatively little research has directly compared the utility of LFPs to action potentials in decoding movement direction in human motor cortex. Approach. We conducted intracortical multi-electrode recordings in motor cortex of two persons (T2 and [S3]) as they performed a motor imagery task. We then compared the offline decoding performance of LFPs and spiking extracted from the same data recorded across a one-year period in each participant. Main results. We obtained offline prediction accuracy of movement direction and endpoint velocity in multiple LFP bands, with the best performance in the highest (200-400 Hz) LFP frequency band, presumably also containing low-pass filtered action potentials. Cross-frequency correlations of preferred directions and directional modulation index showed high similarity of directional information between action potential firing rates (spiking) and high frequency LFPs (70-400 Hz), and increasing disparity with lower frequency bands (0-7, 10-40 and 50-65 Hz). Spikes predicted the direction of intended movement more accurately than any individual LFP band, however combined decoding of all LFPs was statistically indistinguishable from spike-based performance. As the quality of spiking signals (i.e. signal amplitude) and the number of significantly modulated spiking units decreased, the offline decoding performance decreased 3.6[5.65]%/month (for T2 and [S3] respectively). The decrease in the number of significantly modulated LFP signals and their decoding accuracy followed a similar trend (2.4[2.85]%/month, ANCOVA, p = 0.27[0.03]). Significance. Field potentials provided comparable

  1. Reliability of ICD-10 external cause of death codes in the National Coroners Information System.

    PubMed

    Bugeja, Lyndal; Clapperton, Angela J; Killian, Jessica J; Stephan, Karen L; Ozanne-Smith, Joan

    2010-01-01

    Availability of ICD-10 cause of death codes in the National Coroners Information System (NCIS) strengthens its value as a public health surveillance tool. This study quantified the completeness of external cause ICD-10 codes in the NCIS for Victorian deaths (as assigned by the Australian Bureau of Statistics (ABS) in the yearly Cause of Death data). It also examined the concordance between external cause ICD-10 codes contained in the NCIS and a re-code of the same deaths conducted by an independent coder. Of 7,400 NCIS external cause deaths included in this study, 961 (13.0%) did not contain an ABS assigned ICD-10 code and 225 (3.0%) contained only a natural cause code. Where an ABS assigned external cause ICD-10 code was present (n=6,214), 4,397 (70.8%) matched exactly with the independently assigned ICD-10 code. Coding disparity primarily related to differences in assignment of intent and specificity. However, in a small number of deaths (n=49, 0.8%) there was coding disparity for both intent and external cause category. NCIS users should be aware of the limitations of relying only on ICD-10 codes contained within the NCIS for deaths prior to 2007 and consider using these in combination with the other NCIS data fields and code sets to ensure optimum case identification. PMID:21041843

  2. Toward reliable retrieval of functional information of papillary dermis using spatially resolved diffuse reflectance spectroscopy.

    PubMed

    Chen, Yu-Wen; Guo, Jun-Yen; Tzeng, Shih-Yu; Chou, Ting-Chun; Lin, Ming-Jen; Huang, Lynn Ling-Huei; Yang, Chao-Chun; Hsu, Chao-Kai; Tseng, Sheng-Hao

    2016-02-01

    Spatially resolved diffuse reflectance spectroscopy (SRDRS) has been employed to quantify tissue optical properties and its interrogation volume is majorly controlled by the source-to-detector separations (SDSs). To noninvasively quantify properties of dermis, a SRDRS setup that includes SDS shorter than 1 mm is required. It will be demonstrated in this study that Monte Carlo simulations employing the Henyey-Greenstein phase function cannot always precisely predict experimentally measured diffuse reflectance at such short SDSs, and we speculated this could be caused by the non-negligible backward light scattering at short SDSs that cannot be properly modeled by the Henyey-Greenstein phase function. To accurately recover the optical properties and functional information of dermis using SRDRS, we proposed the use of the modified two-layer (MTL) geometry. Monte Carlo simulations and phantom experiment results revealed that the MTL probing geometry was capable of faithfully recovering the optical properties of upper dermis. The capability of the MTL geometry in probing the upper dermis properties was further verified through a swine study, and it was found that the measurement results were reasonably linked to histological findings. Finally, the MTL probe was utilized to study psoriatic lesions. Our results showed that the MTL probe was sensitive to the physiological condition of tissue volumes within the papillary dermis and could be used in studying the physiology of psoriasis. PMID:26977361

  3. Toward reliable retrieval of functional information of papillary dermis using spatially resolved diffuse reflectance spectroscopy

    PubMed Central

    Chen, Yu-Wen; Guo, Jun-Yen; Tzeng, Shih-Yu; Chou, Ting-Chun; Lin, Ming-Jen; Huang, Lynn Ling-Huei; Yang, Chao-Chun; Hsu, Chao-Kai; Tseng, Sheng-Hao

    2016-01-01

    Spatially resolved diffuse reflectance spectroscopy (SRDRS) has been employed to quantify tissue optical properties and its interrogation volume is majorly controlled by the source-to-detector separations (SDSs). To noninvasively quantify properties of dermis, a SRDRS setup that includes SDS shorter than 1 mm is required. It will be demonstrated in this study that Monte Carlo simulations employing the Henyey-Greenstein phase function cannot always precisely predict experimentally measured diffuse reflectance at such short SDSs, and we speculated this could be caused by the non-negligible backward light scattering at short SDSs that cannot be properly modeled by the Henyey-Greenstein phase function. To accurately recover the optical properties and functional information of dermis using SRDRS, we proposed the use of the modified two-layer (MTL) geometry. Monte Carlo simulations and phantom experiment results revealed that the MTL probing geometry was capable of faithfully recovering the optical properties of upper dermis. The capability of the MTL geometry in probing the upper dermis properties was further verified through a swine study, and it was found that the measurement results were reasonably linked to histological findings. Finally, the MTL probe was utilized to study psoriatic lesions. Our results showed that the MTL probe was sensitive to the physiological condition of tissue volumes within the papillary dermis and could be used in studying the physiology of psoriasis. PMID:26977361

  4. Reliability and Maintainability (RAM) Training

    NASA Technical Reports Server (NTRS)

    Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Packard, Michael H. (Editor)

    2000-01-01

    The theme of this manual is failure physics-the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low-cost reliable products. In a broader sense the manual should do more. It should underscore the urgent need CI for mature attitudes toward reliability. Five of the chapters were originally presented as a classroom course to over 1000 Martin Marietta engineers and technicians. Another four chapters and three appendixes have been added, We begin with a view of reliability from the years 1940 to 2000. Chapter 2 starts the training material with a review of mathematics and a description of what elements contribute to product failures. The remaining chapters elucidate basic reliability theory and the disciplines that allow us to control and eliminate failures.

  5. The Comparative Effects of Two Laboratory Approaches on Informational Achievement, Informational Retention and Attitudes in Wood Technology at the College Level.

    ERIC Educational Resources Information Center

    Landers, Jack M.

    Using a project-approach treatment and an exercise/experiment-approach treatment administered to twenty subjects in each of the two groups studied, this research attempted to compare the relative effectiveness of the two approaches to laboratory activity in an industrial arts course at Central Mississippi State College. Informational achievement,…

  6. Aspects of the Relationship of Cultural Information to Motivation and Achievement in Foreign Language Acquisition.

    ERIC Educational Resources Information Center

    Bedford, David A.

    1981-01-01

    Describes experiment carried out at the University of Texas at Austin to test hypothesis that the inclusion of cultural information describing society of language being studied would increase occurrence of integrative motivation in students and this would result in superior acquisition of cognitive language skills. Results neither proved nor…

  7. Relations between Informational Sources, Self-Efficacy and Academic Achievement: A Developmental Approach

    ERIC Educational Resources Information Center

    Phan, Huy Phuong

    2012-01-01

    As a cognitive-motivational construct, self-efficacy has been researched extensively and has involved two important lines of inquiries, namely the impact of sources of information on self-efficacy and the predictive effect of self-efficacy on learning outcomes. We proposed and tested the relations between the four major sources of information…

  8. Utilizing Information and Communication Technologies to Achieve Lifelong Education for All: A Case Study of Myanmar

    ERIC Educational Resources Information Center

    Mar, Naing Yee

    2004-01-01

    This paper examines the role of information and communication technologies (ICTs) in advancing the cause of education for all and livelong learning. After examining the claimed benefits of ICTs for promoting education and schooling, and the characteristics of education and the basic education movement in Asia, the paper focuses on providing a case…

  9. An Informal Reading Readiness Inventory: A Diagnostic Method of Predicting First Grade Reading Achievement.

    ERIC Educational Resources Information Center

    Anderson, Carolyn C.; Koenke, Karl

    A study was undertaken to create and validate a diagnostic, task-based Informal Reading Readiness Inventory (IRRI). IRRI subtests were created to reflect four areas found to be important in reading readiness: awareness of self and media, language experience, reasoning, and phonics. Prereading curriculum components formed the basis for test item…

  10. Decision-Making, Information Communication Technology, and Data Analysis by School Leaders about Student Achievement

    ERIC Educational Resources Information Center

    Akoma, Ahunna Margaux

    2012-01-01

    This case study of one school district examined how school leaders use student performance data and technology-based data analysis tools to engage in data-informed decision-making for continuous improvement. School leaders in this context included leaders at the district, school, and classroom levels. An extensive literature review provided the…

  11. National Library of Medicine Disaster Information Management Research Center: Achieving the vision, 2010–2013

    PubMed Central

    Love, Cynthia B.; Arnesen, Stacey J.; Phillips, Steven J.; Windom, Robert E.

    2016-01-01

    From 2010 to 2013, the National Library of Medicine (NLM) Disaster Information Management Research Center (DIMRC) continued to build its programs and services on the foundation laid in its starting years, 2008–2010. Prior to 2008, NLM had a long history of providing health information, training, and tools in response to disasters. Aware of this legacy, the NLM long range plan (Charting a Course for the 21st Century: NLM’s Long Range Plan 2006–2016) called for creation of a center to show “a strong commitment to disaster remediation and to provide a platform for demonstrating how libraries and librarians can be part of the solution to this national problem”. NLM is continuing efforts to ensure that medical libraries have plans for the continuity of their operations, librarians are trained to understand their roles in preparedness and response, online disaster health information resources are available for many audiences and in multiple formats, and research is conducted on tools to enhance the exchange of critical information during and following disasters. This paper describes the 2010–2013 goals and activities of DIMRC and its future plans. PMID:27570333

  12. Qualitative Parameters for Evaluation Procedures of Non-Formal and Informal Learning Achievements

    ERIC Educational Resources Information Center

    Stasiunaitiene, Egle; Kaminskiene, Lina

    2009-01-01

    The article introduces evaluation principles of non-formal and informal learning that determine the quality of evaluation, describes stages of the evaluation procedure, differentiates their qualitative parameters and defines their criteria and indicators. It also brings in the discussion that consideration of qualitative parameters for the…

  13. Robust fusion with reliabilities weights

    NASA Astrophysics Data System (ADS)

    Grandin, Jean-Francois; Marques, Miguel

    2002-03-01

    The reliability is a value of the degree of trust in a given measurement. We analyze and compare: ML (Classical Maximum Likelihood), MLE (Maximum Likelihood weighted by Entropy), MLR (Maximum Likelihood weighted by Reliability), MLRE (Maximum Likelihood weighted by Reliability and Entropy), DS (Credibility Plausibility), DSR (DS weighted by reliabilities). The analysis is based on a model of a dynamical fusion process. It is composed of three sensors, which have each it's own discriminatory capacity, reliability rate, unknown bias and measurement noise. The knowledge of uncertainties is also severely corrupted, in order to analyze the robustness of the different fusion operators. Two sensor models are used: the first type of sensor is able to estimate the probability of each elementary hypothesis (probabilistic masses), the second type of sensor delivers masses on union of elementary hypotheses (DS masses). In the second case probabilistic reasoning leads to sharing the mass abusively between elementary hypotheses. Compared to the classical ML or DS which achieves just 50% of correct classification in some experiments, DSR, MLE, MLR and MLRE reveals very good performances on all experiments (more than 80% of correct classification rate). The experiment was performed with large variations of the reliability coefficients for each sensor (from 0 to 1), and with large variations on the knowledge of these coefficients (from 0 0.8). All four operators reveal good robustness, but the MLR reveals to be uniformly dominant on all the experiments in the Bayesian case and achieves the best mean performance under incomplete a priori information.

  14. Achievable Steps Toward Building a National Health Information Infrastructure in the United States

    PubMed Central

    Stead, William W.; Kelly, Brian J.; Kolodner, Robert M.

    2005-01-01

    Consensus is growing that a health care information and communication infrastructure is one key to fixing the crisis in the United States in health care quality, cost, and access. The National Health Information Infrastructure (NHII) is an initiative of the Department of Health and Human Services receiving bipartisan support. There are many possible courses toward its objective. Decision makers need to reflect carefully on which approaches are likely to work on a large enough scale to have the intended beneficial national impacts and which are better left to smaller projects within the boundaries of health care organizations. This report provides a primer for use by informatics professionals as they explain aspects of that dividing line to policy makers and to health care leaders and front-line providers. It then identifies short-term, intermediate, and long-term steps that might be taken by the NHII initiative. PMID:15561783

  15. Ethical issues in implementation research: a discussion of the problems in achieving informed consent

    PubMed Central

    Hutton, Jane L; Eccles, Martin P; Grimshaw, Jeremy M

    2008-01-01

    Background Improved quality of care is a policy objective of health care systems around the world. Implementation research is the scientific study of methods to promote the systematic uptake of clinical research findings into routine clinical practice, and hence to reduce inappropriate care. It includes the study of influences on healthcare professionals' behaviour and methods to enable them to use research findings more effectively. Cluster randomized trials represent the optimal design for evaluating the effectiveness of implementation strategies. Various codes of medical ethics, such as the Nuremberg Code and the Declaration of Helsinki inform medical research, but their relevance to cluster randomised trials in implementation research is unclear. This paper discusses the applicability of various ethical codes to obtaining consent in cluster trials in implementation research. Discussion The appropriate application of biomedical codes to implementation research is not obvious. Discussion of the nature and practice of informed consent in implementation research cluster trials must consider the levels at which consent can be sought, and for what purpose it can be sought. The level at which an intervention is delivered can render the idea of patient level consent meaningless. Careful consideration of the ownership of information, and rights of access to and exploitation of data is required. For health care professionals and organizations, there is a balance between clinical freedom and responsibility to participate in research. Summary While ethical justification for clinical trials relies heavily on individual consent, for implementation research aspects of distributive justice, economics, and political philosophy underlie the debate. Societies may need to trade off decisions on the choice between individualized consent and valid implementation research. We suggest that social sciences codes could usefully inform the consideration of implementation research by

  16. Leveraging health information technology to achieve the “triple aim” of healthcare reform

    PubMed Central

    Sood, Harpreet S; Bates, David W

    2015-01-01

    Objective To investigate experiences with leveraging health information technology (HIT) to improve patient care and population health, and reduce healthcare expenditures. Materials and methods In-depth qualitative interviews with federal government employees, health policy, HIT and medico-legal experts, health providers, physicians, purchasers, payers, patient advocates, and vendors from across the United States. Results The authors undertook 47 interviews. There was a widely shared belief that Health Information Technology for Economic and Clinical Health (HITECH) had catalyzed the creation of a digital infrastructure, which was being used in innovative ways to improve quality of care and curtail costs. There were however major concerns about the poor usability of electronic health records (EHRs), their limited ability to support multi-disciplinary care, and major difficulties with health information exchange, which undermined efforts to deliver integrated patient-centered care. Proposed strategies for enhancing the benefits of HIT included federal stimulation of competition by mandating vendors to open-up their application program interfaces, incenting development of low-cost consumer informatics tools, and promoting Congressional review of the The Health Insurance Portability and Accountability Act (HIPPA) to optimize the balance between data privacy and reuse. Many underscored the need to “kick the legs from underneath the fee-for-service model” and replace it with a data-driven reimbursement system that rewards high quality care. Conclusions The HITECH Act has stimulated unprecedented, multi-stakeholder interest in HIT. Early experiences indicate that the resulting digital infrastructure is being used to improve quality of care and curtail costs. Reform efforts are however severely limited by problems with usability, limited interoperability and the persistence of the fee-for-service paradigm—addressing these issues therefore needs to be the federal

  17. Reliability and relative weighting of visual and nonvisual information for perceiving direction of self-motion during walking.

    PubMed

    Saunders, Jeffrey A

    2014-01-01

    Direction of self-motion during walking is indicated by multiple cues, including optic flow, nonvisual sensory cues, and motor prediction. I measured the reliability of perceived heading from visual and nonvisual cues during walking, and whether cues are weighted in an optimal manner. I used a heading alignment task to measure perceived heading during walking. Observers walked toward a target in a virtual environment with and without global optic flow. The target was simulated to be infinitely far away, so that it did not provide direct feedback about direction of self-motion. Variability in heading direction was low even without optic flow, with average RMS error of 2.4°. Global optic flow reduced variability to 1.9°-2.1°, depending on the structure of the environment. The small amount of variance reduction was consistent with optimal use of visual information. The relative contribution of visual and nonvisual information was also measured using cue conflict conditions. Optic flow specified a conflicting heading direction (±5°), and bias in walking direction was used to infer relative weighting. Visual feedback influenced heading direction by 16%-34% depending on scene structure, with more effect with dense motion parallax. The weighting of visual feedback was close to the predictions of an optimal integration model given the observed variability measures. PMID:24648194

  18. School climate, peer victimization, and academic achievement: results from a multi-informant study.

    PubMed

    Wang, Weijun; Vaillancourt, Tracy; Brittain, Heather L; McDougall, Patricia; Krygsman, Amanda; Smith, David; Cunningham, Charles E; Haltigan, J D; Hymel, Shelley

    2014-09-01

    School-level school climate was examined in relation to self-reported peer victimization and teacher-rated academic achievement (grade point average; GPA). Participants included a sample of 1,023 fifth-grade children nested within 50 schools. Associations between peer victimization, school climate, and GPA were examined using multilevel modeling, with school climate as a contextual variable. Boys and girls reported no differences in victimization by their peers, although boys had lower GPAs than girls. Peer victimization was related to lower GPA and to a poorer perception of school climate (individual-level), which was also associated with lower GPA. Results of multilevel analyses revealed that peer victimization was again negatively associated with GPA, and that lower school-level climate was associated with lower GPA. Although no moderating effects of school-level school climate or sex were observed, the relation between peer victimization and GPA remained significant after taking into account (a) school-level climate scores, (b) individual variability in school-climate scores, and (c) several covariates--ethnicity, absenteeism, household income, parental education, percentage of minority students, type of school, and bullying perpetration. These findings underscore the importance of a positive school climate for academic success and viewing school climate as a fundamental collective school outcome. Results also speak to the importance of viewing peer victimization as being harmfully linked to students' academic performance. PMID:25198617

  19. Achieving Informed Consent for Cellular Therapies: A Preclinical Translational Research Perspective on Regulations versus a Dose of Reality.

    PubMed

    Anderson, Aileen J; Cummings, Brian J

    2016-09-01

    A central principle of bioethics is "subject autonomy," the acknowledgement of the primacy of the informed consent of the subject of research. Autonomy requires informed consent - the assurance that the research participant is informed about the possible risks and benefits of the research. In fact, informed consent is difficult when a single drug is being tested, although subjects have a baseline understanding of the testing of a pharmacological agent and the understanding that they can stop taking the drug if there were an adverse event. However, informed consent is even less easily achieved in the modern arena of complex new molecular and cellular therapies. In this article, we argue that as science confronts new issues such as transplantation of stem cell products, which may live within the participant for the rest of their lives, researchers must carefully consider and constantly re-examine how they properly inform subjects considering participation trials of these novel therapeutic strategies.For example, the manufacture of a vial of a cell product that consists of a collection of growing cells is very different than the production of a vial of identical pills, which can be presumed to be identical. The scientific concepts on which these cellular approaches are based may seem alien and incomprehensible to a research subject, who thinks of a clinical trial as simply the selection and testing of the most efficacious pharmaceutical agent already proven to work in preclinical animal studies. The research subject would be wrong. PMID:27587445

  20. Information processes in visual and object buffers of scene understanding system for reliable target detection, separation from background, and identification

    NASA Astrophysics Data System (ADS)

    Kuvich, Gary

    2006-05-01

    Modern target recognition systems suffer from the lack of human-like abilities to understand the visual scene, detect, unambiguously identify and recognize objects. As result, the target recognition systems become dysfunctional if target doesn't demonstrate remarkably distinctive and contrast features that allow for unambiguous separation from background and identification upon such features. This is somewhat similar to visual systems of primitive animals like frogs, which can separate and recognize only moving objects. However, human vision unambiguously separates any object from its background. Human vision combines a rough but wide peripheral, and narrow but precise foveal systems with visual intelligence that utilize both scene and object contexts and resolve ambiguity and uncertainty in the visual information. Perceptual grouping is one of the most important processes in human vision, and it binds visual information into meaningful patterns and structures. Unlike the traditional computer vision models, biologically-inspired Network-Symbolic models convert image information into an "understandable" Network-Symbolic format, which is similar to relational knowledge models. The equivalent of interaction between peripheral and foveal systems in the network-symbolic system is achieved via interaction between Visual and Object Buffers and the top-level system of Visual Intelligence. This interaction provides recursive rough context identification of regions of interest in the visual scene and their analysis in the object buffer for precise and unambiguous separation of the object from background/clutter with following recognition of the target.

  1. The relationship of learning motivation, achievement and satisfaction for nurses learning simple excel VBA information systems programming.

    PubMed

    Lee, Ying Li; Chien, Tsai Feng; Kuo, Ming Chuan; Chang, Polun

    2014-01-01

    This study aims to understand the relationship between participating nurses' motivation, achievement and satisfaction before and after they learned to program in Excel Visual Basic for Applications (Excel VBA). We held a workshop to train nurses in developing simple Excel VBA information systems to support their clinical or administrative practices. Before and after the workshop, the participants were evaluated on their knowledge of Excel VBA, and a questionnaire was given to survey their learning motivation and satisfaction. Statistics softwares Winsteps and SPSS were used for data analysis. Results show that the participants are more knowledgeable about VBA as well as more motivated in learning VBA after the workshop. Participants were highly satisfied with the overall arrangement of the workshop and instructors, but didn't have enough confidence in promoting the application of Excel VBA themselves. In addition, we were unable to predict the participants' achievement by their demographic characteristics or pre-test motivation level. PMID:24943568

  2. Network reliability

    NASA Technical Reports Server (NTRS)

    Johnson, Marjory J.

    1985-01-01

    Network control (or network management) functions are essential for efficient and reliable operation of a network. Some control functions are currently included as part of the Open System Interconnection model. For local area networks, it is widely recognized that there is a need for additional control functions, including fault isolation functions, monitoring functions, and configuration functions. These functions can be implemented in either a central or distributed manner. The Fiber Distributed Data Interface Medium Access Control and Station Management protocols provide an example of distributed implementation. Relative information is presented here in outline form.

  3. Gearbox Reliability Collaborative Update (Presentation)

    SciTech Connect

    Sheng, S.

    2013-10-01

    This presentation was given at the Sandia Reliability Workshop in August 2013 and provides information on current statistics, a status update, next steps, and other reliability research and development activities related to the Gearbox Reliability Collaborative.

  4. Brief Report: How Do They Manage Social Interaction? The Influence of Concealing Academic Achievement Information on Self-Monitoring by Adolescents with Low Achievement

    ERIC Educational Resources Information Center

    Zhang, Baoshan; Zhao, Jun-Yan; Yu, Guoliang

    2010-01-01

    During social interactions people self-monitor their behavior at least partially to conceal socially devalued characteristics. This study examined the influences of concealing academic achievement on self-monitoring in an academically-relevant social interaction. An interview paradigm called for school-aged adolescent participants (total N = 86)…

  5. Readability and Test-Retest Reliability of a Psychometric Instrument Designed to Assess HIV/AIDS Attitudes, Beliefs, Behaviours and Sources of HIV Prevention Information of Young Adults

    ERIC Educational Resources Information Center

    Balogun, Joseph; Abiona, Titilayo; Lukobo-Durrell, Mainza; Adefuye, Adedeji; Amosun, Seyi; Frantz, Jose; Yakut, Yavuz

    2011-01-01

    Objective: This comparative study evaluated the readability and test-retest reliability of a questionnaire designed to assess the attitudes, beliefs behaviours and sources of information about HIV/AIDS among young adults recruited from universities in the United States of America (USA), Turkey and South Africa. Design/Setting: The instrument was…

  6. CISN Display Progress to Date - Reliable Delivery of Real-Time Earthquake Information, and ShakeMap to Critical End Users

    NASA Astrophysics Data System (ADS)

    Rico, H.; Hauksson, E.; Thomas, E.; Friberg, P.; Frechette, K.; Given, D.

    2003-12-01

    can give Emergency Response managers' information needed to allocate limited personnel and resources after a major event. The shaking intensity shape files may be downloaded out-of-band to the client computer, and with the GIS mapping tool, users can plot organizational assets on the CISN Display map and analyze their inventory against potentially damaged areas. Lastly, in support of a robust design is a well-established and reliable set of communication protocols. To achieve a state-full server connection and messaging via a signaling channel the application uses a Common Object Request Broker Architecture (CORBA). The client responds to keep-alive signals from the server, and alerts users of changes in the connection status. This full-featured messaging service will allow the system to trigger a reconnect strategy whenever the client detects a loss of connectivity. This sets the CISN Display apart from its predecessors, which do not provide a failover mechanism, or a state of connection. Thus by building on past programming successes and advances in proven Internet technologies, the CISN Display will augment the emergency responder's ability to make informed decisions following a potentially damaging earthquake.

  7. 'Give us the full story': overcoming the challenges to achieving informed choice about fetal anomaly screening in Australian Aboriginal communities.

    PubMed

    Wild, Kayli; Maypilama, Elaine Lawurrpa; Kildea, Sue; Boyle, Jacqueline; Barclay, Lesley; Rumbold, Alice

    2013-12-01

    This cross-cultural qualitative study examined the ethical, language and cultural complexities around offering fetal anomaly screening in Australian Aboriginal communities. There were five study sites across the Northern Territory (NT), including urban and remote Aboriginal communities. In-depth interviews were conducted between October 2009 and August 2010, and included 35 interviews with 59 health providers and 33 interviews with 62 Aboriginal women. The findings show that while many providers espoused the importance of achieving equity in access to fetal anomaly screening, their actions were inconsistent with this ideal. Providers reported they often modified their practice depending on the characteristics of their client, including their English skills, the perception of the woman's interest in the tests and assumptions based on their risk profile and cultural background. Health providers were unsure whether it was better to tailor information to the specific needs of their client or to provide the same level of information to all clients. Very few Aboriginal women were aware of fetal anomaly screening. The research revealed they did want to be offered screening and wanted the 'full story' about all aspects of the tests. The communication processes advocated by Aboriginal women to improve understanding about screening included community discussions led by elders and educators. These processes promote culturally defined ways of sharing information, rather than the individualised, biomedical approaches to information-giving in the clinical setting. A different and arguably more ethical approach to introducing fetal anomaly screening would be to initiate dialogue with appropriate groups of women in the community, particularly young women, build relationships and utilise Aboriginal health workers. This could accommodate individual choice and broader cultural values and allow women to discuss the moral and philosophical debates surrounding fetal anomaly screening

  8. Being an Informed Consumer of Health Information and Assessment of Electronic Health Literacy in a National Sample of Internet Users: Validity and Reliability of the e-HLS Instrument

    PubMed Central

    Yeatts, Dale; Hughes, Susan; Hudson, Cassie; Bell, Valarie

    2016-01-01

    Background The Internet, with its capacity to provide information that transcends time and space barriers, continues to transform how people find and apply information to their own lives. With the current explosion in electronic sources of health information, including thousands of websites and hundreds of mobile phone health apps, electronic health literacy is gaining an increasing prominence in health and medical research. An important dimension of electronic health literacy is the ability to appraise the quality of information that will facilitate everyday health care decisions. Health information seekers explore their care options by gathering information from health websites, blogs, Web-based forums, social networking websites, and advertisements, despite the fact that information quality on the Internet varies greatly. Nonetheless, research has lagged behind in establishing multidimensional instruments, in part due to the evolving construct of health literacy itself. Objective The purpose of this study was to examine psychometric properties of a new electronic health literacy (ehealth literacy) measure in a national sample of Internet users with specific attention to older users. Our paper is motivated by the fact that ehealth literacy is an underinvestigated area of inquiry. Methods Our sample was drawn from a panel of more than 55,000 participants maintained by Knowledge Networks, the largest national probability-based research panel for Web-based surveys. We examined the factor structure of a 19-item electronic Health Literacy Scale (e-HLS) through exploratory factor analysis (EFA) and confirmatory factor analysis, internal consistency reliability, and construct validity on sample of adults (n=710) and a subsample of older adults (n=194). The AMOS graphics program 21.0 was used to construct a measurement model, linking latent factors obtained from EFA with 19 indicators to determine whether this factor structure achieved a good fit with our entire sample

  9. Testing the Mediating Role of Teachers' Self-Efficacy Beliefs in the Relationship between Sources of Efficacy Information and Students Achievement

    ERIC Educational Resources Information Center

    Mohamadi, Fatemeh Shaterian; Asadzadeh, Hassan

    2012-01-01

    The purpose of this study is to test the mediating role of teachers' self-efficacy beliefs in the relationship between sources of efficacy information and students achievement. For achieving this aim, this study suggests two alternative models, tested by Structural equation modeling (SEM) technique. In the first model, sources of efficacy…

  10. Parts, Materials, and Processes Experience Summary. Volume 1; [Catalog of ALERT and Other Information on Basic Design, Reliability, Quality and Applications Programs

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The ALERT program, a system for communicating common problems with parts, materials, and processes, is condensed and catalogued. Expanded information on selected topics is provided by relating the problem area (failure) to the cause, the investigations and findings, the suggestions for avoidance (inspections, screening tests, proper part applications), and failure analysis procedures. The basic objective of ALERT is the avoidance of the recurrence of parts, materials, and processed problems, thus improving the reliability of equipment produced for and used by the government.

  11. Associations between Reading Achievement and Independent Reading in Early Elementary School: A Genetically Informative Cross-Lagged Study

    ERIC Educational Resources Information Center

    Harlaar, Nicole; Deater-Deckard, Kirby; Thompson, Lee A.; DeThorne, Laura S.; Petrill, Stephen A.

    2011-01-01

    This study used a cross-lagged twin design to examine reading achievement and independent reading from 10 to 11 years (n = 436 twin pairs). Reading achievement at age 10 significantly predicted independent reading at age 11. The alternative path, from independent reading at age 10 to reading achievement at age 11, was not significant. Individual…

  12. Development and reliability of a scale of physical-activity related informal social control for parents of Chinese pre-schoolers

    PubMed Central

    2014-01-01

    Background Parents’ perceived informal social control, defined as the informal ways residents intervene to create a safe and orderly neighbourhood environment, may influence young children’s physical activity (PA) in the neighbourhood. This study aimed to develop and test the reliability of a scale of PA-related informal social control relevant to Chinese parents/caregivers of pre-schoolers (children aged 3 to 5 years) living in Hong Kong. Methods Nominal Group Technique (NGT), a structured, multi-step brainstorming technique, was conducted with two groups of caregivers (mainly parents; n = 11) of Hong Kong pre-schoolers in June 2011. Items collected in the NGT sessions and those generated by a panel of experts were used to compile a list of items (n = 22) for a preliminary version of a questionnaire of informal social control. The newly-developed scale was tested with 20 Chinese-speaking parents/caregivers using cognitive interviews (August 2011). The modified scale, including all 22 original items of which a few were slightly reworded, was subsequently administered on two occasions, a week apart, to 61 Chinese parents/caregivers of Hong Kong pre-schoolers in early 2012. The test-retest reliability and internal consistency of the items and scale were examined using intraclass correlation coefficients (ICC), paired t-tests, relative percentages of shifts in responses to items, and Cronbach’s α coefficient. Results Thirteen items generated by parents/caregivers and nine items generated by the panel of experts (total 22 items) were included in a first working version of the scale and classified into three subscales: “Personal involvement and general informal supervision”, “Civic engagement for the creation of a better neighbourhood environment” and “Educating and assisting neighbourhood children”. Twenty out of 22 items showed moderate to excellent test-test reliability (ICC range: 0.40-0.81). All three subscales of informal social control

  13. Reliability of health information for the public on the World Wide Web: systematic survey of advice on managing fever in children at home.

    PubMed Central

    Impicciatore, P.; Pandolfini, C.; Casella, N.; Bonati, M.

    1997-01-01

    OBJECTIVE: To assess the reliability of healthcare information on the world wide web and therefore how it may help lay people cope with common health problems. METHODS: Systematic search by means of two search engines, Yahoo and Excite, of parent oriented web pages relating to home management of feverish children. Reliability of information on the web sites was checked by comparison with published guidelines. MAIN OUTCOME MEASURES: Minimum temperature of child that should be considered as fever, optimal sites for measuring temperature, pharmacological and physical treatment of fever, conditions that may warrant a doctor's visit. RESULTS: 41 web pages were retrieved and considered. 28 web pages gave a temperature above which a child is feverish; 26 pages indicated the optimal site for taking temperature, most recommending rectal measurement; 31 of the 34 pages that mentioned drug treatment recommended paracetamol as an antipyretic; 38 pages recommended non-drug measures, most commonly tepid sponging, dressing lightly, and increasing fluid intake; and 36 pages gave some indication of when a doctor should be called. Only four web pages adhered closely to the main recommendations in the guidelines. The largest deviations were in sponging procedures and how to take a child's temperature, whereas there was a general agreement in the use of paracetamol. CONCLUSIONS: Only a few web sites provided complete and accurate information for this common and widely discussed condition. This suggests an urgent need to check public oriented healthcare information on the internet for accuracy, completeness, and consistency. PMID:9224132

  14. Child Welfare: Most States Are Developing Statewide Information Systems, but Reliability of Child Welfare Data Could Be Improved.

    ERIC Educational Resources Information Center

    Pietrowiak, Diana; Schibanoff, Sara L.

    To better monitor children and families served by state child welfare agencies, Congress authorized matching funds for the development of statewide automatic child welfare information systems (SACWIS) and required that U.S. Department of Health and Human Services (HHS) compile information on children served by state agencies. This report to…

  15. Reliability design for impact vibration of hydraulic pressure pipeline systems

    NASA Astrophysics Data System (ADS)

    Zhang, Tianxiao; Liu, Xinhui

    2013-09-01

    The research of reliability design for impact vibration of hydraulic pressure pipeline systems is still in the primary stage, and the research of quantitative reliability of hydraulic components and system is still incomplete. On the condition of having obtained the numerical characteristics of basic random parameters, several techniques and methods including the probability statistical theory, hydraulic technique and stochastic perturbation method are employed to carry out the reliability design for impact vibration of the hydraulic pressure system. Considering the instantaneous pressure pulse of hydraulic impact in pipeline, the reliability analysis model of hydraulic pipeline system is established, and the reliability-based optimization design method is presented. The proposed method can reflect the inherent reliability of hydraulic pipe system exactly, and the desired result is obtained. The reliability design of hydraulic pipeline system is achieved by computer programs and the reliability design information of hydraulic pipeline system is obtained. This research proposes a reliability design method, which can solve the problem of the reliability-based optimization design for the hydraulic pressure system with impact vibration practically and effectively, and enhance the quantitative research on the reliability design of hydraulic pipeline system. The proposed method has generality for the reliability optimization design of hydraulic pipeline system.

  16. Museum-based learning: Informal learning settings and their role in student motivation and achievement in science

    NASA Astrophysics Data System (ADS)

    Holmes, Julie Ann

    This study examined changes in student motivation and achievement in science in relationship with a visit to the IDEA Place Experiment Gallery. The study was based on the pretest-posttest control comparison group design with four treatment groups: control, exhibit, lesson, and exhibit/lesson. The sample was 228 sixth grade students from a public north central Louisiana school who were randomly assigned to one of the four experimental groups. Pretest, posttest, and delayed posttest measures of intrinsic motivation and achievement in science were determined using the Children's Academic Intrinsic Motivation Inventory and an achievement test written to measure areas of science incorporated in the Experiment Gallery exhibits. The data were analyzed using a one way Analysis of Variance (ANOVA), dependent t tests, and Pearson r. Statistical analysis revealed: (a) no significant differences in motivation or achievement on pretest and posttest scores between groups and, (b) no significant relationships between motivation level and achievement between groups on the posttest. Significant differences were found within groups for (a) the lesson group in motivation, and (b) the exhibit group in achievement from pretest to posttest and from posttest to delayed posttest. A significant relationship between level of motivation and science achievement was revealed for the exhibit group on the delayed posttests. There were no other significant findings to support that the effects of the treatment led to any long term effects on motivation or achievement within any of the four experimental groups.

  17. Associations between reading achievement and independent reading in early elementary school: A genetically-informative cross-lagged study

    PubMed Central

    Harlaar, Nicole; Deater-Deckard, Kirby; Thompson, Lee A.; DeThorne, Laura S.; Petrill, Stephen A.

    2013-01-01

    This study used a cross-lagged twin design to examine reading achievement and independent reading from 10 to 11 years (n = 436 twin pairs). Reading achievement at age 10 significantly predicted independent reading at age 11. The alternative path, from independent reading at age 10 to reading achievement at age 11, was not significant. Individual differences in reading achievement and independent reading at both ages were primarily due to genetic influences. Furthermore, individual differences in independent reading at age 11 partly reflected genetic influences on reading achievement at age 10. These findings suggest that genetic influences that contribute to individual differences in children’s reading abilities also influence the extent to which children actively seek out and create opportunities to read. PMID:22026450

  18. Health Literacy INDEX: development, reliability, and validity of a new tool for evaluating the health literacy demands of health information materials.

    PubMed

    Kaphingst, Kimberly A; Kreuter, Matthew W; Casey, Chris; Leme, Luisa; Thompson, Tess; Cheng, Meng-Ru; Jacobsen, Heather; Sterling, Ryan; Oguntimein, Joy; Filler, Carl; Culbert, Arthur; Rooney, Megan; Lapka, Christy

    2012-01-01

    There is no consensus on how best to assess the health literacy demands of health information materials. Comprehensive, reliable, and valid assessment tools are needed. The authors report on the development, refinement, and testing of Health Literacy INDEX, a new tool reflecting empirical evidence and best practices. INDEX is comprised of 63 indicators organized into 10 criteria: plain language, clear purpose, supporting graphics, user involvement, skill-based learning, audience appropriateness, user instruction, development details, evaluation methods, and strength of evidence. In a sample of 100 materials, intercoder agreement was high: 90% or better for 52% of indicators, and above 80% for nearly all others. Overall scores generated by INDEX were highly correlated with average ratings from 12 health literacy experts (r = 0.89, p < .0001). Additional research is warranted to examine the association between evaluation ratings generated by INDEX and individual understanding, behaviors, and improved health. Health Literacy INDEX is a comprehensive tool with evidence for reliability and validity that can be used to evaluate the health literacy demands of health information materials. Although improvement in health information materials is just one aspect of mitigating the effects of limited health literacy on health outcomes, it is an essential step toward a more health literate public. PMID:23030571

  19. Combining Self-Assessments and Achievement Tests in Information Literacy Assessment: Empirical Results and Recommendations for Practice

    ERIC Educational Resources Information Center

    Rosman, Tom; Mayer, Anne-Kathrin; Krampen, Günter

    2015-01-01

    This article examines the significance of information literacy self-assessments in higher education with a special focus on situational conditions increasing their explanatory power. First, it was hypothesised that self-assessments of information literacy correlate higher with factual information literacy if measured after the administration of…

  20. Materials Reliability Program: Risk-Informed Revision of ASME Section XI Appendix G - Proof of Concept (MRP-143)

    SciTech Connect

    B. Bishop; et al

    2005-03-30

    This study indicates that risk-informed methods can be used to significantly relax the current ASME and NRC Appendix G requirements while still maintaining satisfactory levels of reactor vessel structural integrity. This relaxation in Appendix G requirements directly translates into significant improvements in operational flexibility.

  1. The enzymatic nature of an anonymous protein sequence cannot reliably be inferred from superfamily level structural information alone.

    PubMed

    Roche, Daniel Barry; Brüls, Thomas

    2015-05-01

    As the largest fraction of any proteome does not carry out enzymatic functions, and in order to leverage 3D structural data for the annotation of increasingly higher volumes of sequence data, we wanted to assess the strength of the link between coarse grained structural data (i.e., homologous superfamily level) and the enzymatic versus non-enzymatic nature of protein sequences. To probe this relationship, we took advantage of 41 phylogenetically diverse (encompassing 11 distinct phyla) genomes recently sequenced within the GEBA initiative, for which we integrated structural information, as defined by CATH, with enzyme level information, as defined by Enzyme Commission (EC) numbers. This analysis revealed that only a very small fraction (about 1%) of domain sequences occurring in the analyzed genomes was found to be associated with homologous superfamilies strongly indicative of enzymatic function. Resorting to less stringent criteria to define enzyme versus non-enzyme biased structural classes or excluding highly prevalent folds from the analysis had only modest effect on this proportion. Thus, the low genomic coverage by structurally anchored protein domains strongly associated to catalytic activities indicates that, on its own, the power of coarse grained structural information to infer the general property of being an enzyme is rather limited. PMID:25559918

  2. A reliable user authentication and key agreement scheme for Web-based Hospital-acquired Infection Surveillance Information System.

    PubMed

    Wu, Zhen-Yu; Tseng, Yi-Ju; Chung, Yufang; Chen, Yee-Chun; Lai, Feipei

    2012-08-01

    With the rapid development of the Internet, both digitization and electronic orientation are required on various applications in the daily life. For hospital-acquired infection control, a Web-based Hospital-acquired Infection Surveillance System was implemented. Clinical data from different hospitals and systems were collected and analyzed. The hospital-acquired infection screening rules in this system utilized this information to detect different patterns of defined hospital-acquired infection. Moreover, these data were integrated into the user interface of a signal entry point to assist physicians and healthcare providers in making decisions. Based on Service-Oriented Architecture, web-service techniques which were suitable for integrating heterogeneous platforms, protocols, and applications, were used. In summary, this system simplifies the workflow of hospital infection control and improves the healthcare quality. However, it is probable for attackers to intercept the process of data transmission or access to the user interface. To tackle the illegal access and to prevent the information from being stolen during transmission over the insecure Internet, a password-based user authentication scheme is proposed for information integrity. PMID:21556897

  3. Correlation Between the General Information Subtest of the Peabody Individual Achievement Test and the Full Scale Intelligence Quotient of the WISC-R.

    ERIC Educational Resources Information Center

    Simpson, Robert G.

    1982-01-01

    The usefulness of the Peabody Individual Achievement Test General Information subtest as a general screening instrument with non-retarded subjects is shown in a study of concurrent validity between the subtest and the Wechsler Intelligence Scale for Children-Revised. Correlations between the instruments in two intelligence groups are discussed.…

  4. The Role of Arts-Related Information and Communication Technology Use in Problem Solving and Achievement: Findings from the Programme for International Student Assessment

    ERIC Educational Resources Information Center

    Liem, Gregory Arief D.; Martin, Andrew J.; Anderson, Michael; Gibson, Robyn; Sudmalis, David

    2014-01-01

    Drawing on the Programme for International Student Assessment 2003 data set comprising over 190,000 15-year-old students in 25 countries, the current study sought to examine the role of arts-related information and communication technology (ICT) use in students' problem-solving skill and science and mathematics achievement. Structural equation…

  5. Working Group summary reports from the Advanced Photon Source reliability workshop

    SciTech Connect

    Not Available

    1992-05-01

    A workshop was held at APS to address reliability goals for accelerator systems. Seventy-one individuals participated in the workshop, including 30 from other institutions. The goals of the workshop were to: (1) Give attendees an introduction to the basic concepts of reliability analysis. (2) Exchange information on operating experience at existing accelerator facilities and strategies for achieving reliability at facilities under design or in construction. (3) Discuss reliability goals for APS and the means of their achievement. This report contains the working group summary report an APS`s following systems: RF Systems; Power Supplies; Magnet Systems; Interlock and Diagnostics; and Vacuum Systems.

  6. Working Group summary reports from the Advanced Photon Source reliability workshop

    SciTech Connect

    Not Available

    1992-05-01

    A workshop was held at APS to address reliability goals for accelerator systems. Seventy-one individuals participated in the workshop, including 30 from other institutions. The goals of the workshop were to: (1) Give attendees an introduction to the basic concepts of reliability analysis. (2) Exchange information on operating experience at existing accelerator facilities and strategies for achieving reliability at facilities under design or in construction. (3) Discuss reliability goals for APS and the means of their achievement. This report contains the working group summary report an APS's following systems: RF Systems; Power Supplies; Magnet Systems; Interlock and Diagnostics; and Vacuum Systems.

  7. Use of Student Achievement Information in the Performance Evaluation of Teachers in the Tennessee Career Ladder Program.

    ERIC Educational Resources Information Center

    Furtwengler, Carol B.

    Tennessee initiated a Career Ladder Program for teachers in July 1984. The program is designed to recruit, retain, and reward outstanding teachers. Teachers who obtain upper career ladder status receive financial rewards ranging from 2,000 to 7,000 dollars per year. This status is achieved by participation in a comprehensive evaluation process.…

  8. An Investigation of World Language Teachers' Use of Student Performance Data to Inform Teaching and to Help Improve Student Achievement

    ERIC Educational Resources Information Center

    Koffi, Bruno N.

    2013-01-01

    This qualitative study investigated the types of content-based student performance data World Language teachers used to improve instruction and student academic achievement, the purposes for which they used data, the issues they encountered, and the suggestions they made for more effective use of data. The Standards for Foreign Language Learning…

  9. Date of first positive HIV test: reliability of information collected for HIV/AIDS surveillance in the United States.

    PubMed Central

    Hall, H. Irene; Li, Jianmin; Campsmith, Michael; Sweeny, Patricia; Lee, Lisa M.

    2005-01-01

    OBJECTIVES: This study examined the reliability of the first positive HIV test date reported in the U.S. HIV/AIDS Reporting System (HARS). This date is essential to determine case counts for resource allocation for HIV treatment and prevention efforts. METHODS: The dates of first positive HIV tests reported by individuals with HIV in an interview survey conducted in 16 states (n=16,394, interviewed 1995-2002) were compared with the dates of HIV diagnosis reported to HARS. The percentage of agreement for the year of diagnosis and the weighed kappa (k) with 95% confidence intervals (CIs) was calculated. RESULTS: Self-reported year of diagnosis agreed with the year of diagnosis in HARS for 56% of date pairs (k=0.69; 95% CI 0.68, 0.70); 30% reported an earlier diagnosis year. Agreement differed by sex, age, race, exposure, and reason or place of testing (p<.01). Lower agreement was found when the self-reported diagnostic test was anonymous (k=0.57; 95% CI 0.52, 0.62) compared with confidential tests (k=0.66; 95% CI 0.64, 0.68). Lower agreement was also found for cases first reported with AIDS (k=0.58; 95% CI 0.55, 0.62) compared with cases first reported with HIV not AIDS (k=0.71; 95% CI 0.70, 0.73) as well as for participants interviewed three years or more after their HARS diagnosis date (k=0.55; 95% CI 0.52, 0.57) compared with those interviewed within one year (k=0.62; 95% CI 0.61, 0.63). More than 20% of participants in almost all groups, however, reported earlier diagnosis years than those recorded in HARS. CONCLUSION: As many as 30% of HIV diagnoses may have occurred earlier than recorded in HARS. Additional studies need to determine mechanisms to adequately capture diagnosis dates in HARS. PMID:15736337

  10. Changes in the Use of Graphic and Contextual Information as Functions of Passage Difficulty and Reading Achievement Level.

    ERIC Educational Resources Information Center

    Biemiller, Andrew

    1979-01-01

    Findings from this study suggest that by the end of the first grade, children taught using "meaning emphasis" curricula shift towards increased use of graphic information when confronted with reading material in which words are harder to identify. (HOD)

  11. Reliability physics

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.; Ross, R. G., Jr.

    1984-01-01

    Speakers whose topics relate to the reliability physics of solar arrays are listed and their topics briefly reviewed. Nine reports are reviewed ranging in subjects from studies of photothermal degradation in encapsulants and polymerizable ultraviolet stabilizers to interface bonding stability to electrochemical degradation of photovoltaic modules.

  12. Achieving a Risk-Informed Decision-Making Environment at NASA: The Emphasis of NASA's Risk Management Policy

    NASA Technical Reports Server (NTRS)

    Dezfuli, Homayoon

    2010-01-01

    This slide presentation reviews the evolution of risk management (RM) at NASA. The aim of the RM approach at NASA is to promote an approach that is heuristic, proactive, and coherent across all of NASA. Risk Informed Decision Making (RIDM) is a decision making process that uses a diverse set of performance measures along with other considerations within a deliberative process to inform decision making. RIDM is invoked for key decisions such as architecture and design decisions, make-buy decisions, and budget reallocation. The RIDM process and how it relates to the continuous Risk Management (CRM) process is reviewed.

  13. Achieving Engineering Competencies in the Global Information Society through the Integration of On-Campus and Workplace Environments

    ERIC Educational Resources Information Center

    Allan, Malcolm; Chisholm, Colin U.

    2008-01-01

    Engineering organizations are increasingly under pressure to perform more efficiently with fewer people. To manage this, organizations need to understand what skills, knowledge and behaviours they need from engineers who have to practise in a global information society. Engineering educators, in collaboration with employers, therefore now need to…

  14. A Methodology to Assist Faculty in Developing Successful Approaches for Achieving Learner Centered Information Systems Curriculum Outcomes: Team Based Methods

    ERIC Educational Resources Information Center

    Wagner, Teresa A.; Longenecker, Herbert E., Jr.; Landry, Jeffrey P.; Lusk, C. Scott; Saulnier, Bruce M.

    2008-01-01

    All industries face the interrelated challenges of identifying and training the critical skills needed to be successful in the workplace. Specifically of interest to the information systems field is that any newly trained IS professional has to be equipped to solve increasingly difficult problems with great confidence and competence. In this paper…

  15. How to achieve informed consent for research from Spanish-speaking individuals with low literacy: a qualitative report.

    PubMed

    Cortés, Dharma E; Drainoni, Mari-Lynn; Henault, Lori E; Paasche-Orlow, Michael K

    2010-01-01

    Investigators have the responsibility to ensure that prospective participants are fully informed about a research protocol prior to consenting to participate, yet many researchers face challenges when obtaining consent, since the majority of the general population has limited or no familiarity with research studies. These challenges are further magnified when obtaining consent from individuals with low literacy levels and who speak languages other than English. In this article we present findings from a qualitative study conducted with Spanish-speaking individuals with low-literacy designed to refine the Agency for Healthcare Research and Quality's Informed Consent and Authorization Toolkit for Minimal Risk Research. Findings from this study indicate that familiarity with providing informed consent and authorization for research or the experience of being a research participant appear to play key roles in an individual's ability to understand the consent and authorization process. While the text of the consent and authorization documents can be simplified using plain language principles, comprehension of several fundamental ideas such as risk and privacy need to be safeguarded with a consent process that confirms comprehension. Recommendations are provided to address the informational needs of individuals with low literacy levels and limited or no experience with research participation. PMID:20845202

  16. Intermediate Trends in Math and Science Partnership-Related Changes in Student Achievement with Management Information System Data

    ERIC Educational Resources Information Center

    Dimitrov, Dimiter M.

    2009-01-01

    This substudy in the evaluation design of the Math and Science Partnership (MSP) Program Evaluation examines student proficiency in mathematics and science for the MSPs' schools in terms of changes across three years (2003/04, 2004/05, and 2005/06) and relationships with MSP-related variables using Management Information System data with the…

  17. Towards an Integrated Analytical Framework of Information and Communications Technology Literacy: From Intended to Implemented and Achieved Dimensions

    ERIC Educational Resources Information Center

    Markauskaite, Lina

    2006-01-01

    Introduction: Theoretical approaches and frameworks that help us to understand the contemporary notion of information and communication technology literacy (ICT literacy) in the formal education sector are reviewed and examined. Method: The analysis is conducted from a technology (i.e., computer science) conceptual perspective. The focus is on…

  18. Multidisciplinary System Reliability Analysis

    NASA Technical Reports Server (NTRS)

    Mahadevan, Sankaran; Han, Song; Chamis, Christos C. (Technical Monitor)

    2001-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code, developed under the leadership of NASA Glenn Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multidisciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  19. Achievements of the DOT-NASA Joint Program on Remote Sensing and Spatial Information Technologies: Application to Multimodal Transportation

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This report presents three-year accomplishments from the national program on Commercial Remote Sensing and Geospatial Technology (CRSGT) application to transportation, administered by the U.S. Department of Transportation (U.S. DOT) in collaboration with the National Aeronautics and Space Administration (NASA). The joint program was authorized under Section 5113 of the Transportation Equity Act for the 21st Century (TEA-21). This is the first national program of its type focusing on transportation applications of emerging commercial remote sensing technologies. U.S. DOT's Research and Special Programs Administration manages the program in coordination with NASA's Earth Science Enterprise's application programs. The program focuses on applications of CRSGT products and systems for providing smarter and more efficient transportation operations and services. The program is performed in partnership with four major National Consortia for Remote Sensing in Transportation (NCRST). Each consortium focuses on research and development of products in one of the four priority areas for transportation application, and includes technical application and demonstration projects carried out in partnership with industries and service providers in their respective areas. The report identifies products and accomplishments from each of the four consortia in meeting the goal of providing smarter and more efficient transportation services. The products and results emerging from the program are being implemented in transportation operations and services through state and local agencies. The Environmental Assessment and Application Consortium (NCRST-E) provides leadership for developing and deploying cost effective environmental and transportation planning services, and integrates CRSGT advances for achieving smarter and cost effective corridor planning. The Infrastructure Management Consortium (NCRST-I) provides leadership in technologies that achieve smarter and cheaper ways of managing

  20. Unraveling the sequence information in COI barcode to achieve higher taxon assignment based on Indian freshwater fishes.

    PubMed

    Chakraborty, Mohua; Ghosh, Sankar Kumar

    2015-04-01

    Efficacy of cytochrome c oxidase subunit I (COI) DNA barcode in higher taxon assignment is still under debate in spite of several attempts, using the conventional DNA barcoding methods, to assign higher taxa. Here we try to understand whether nucleotide and amino acid sequence in COI gene carry sufficient information to assign species to their higher taxonomic rank, using 160 species of Indian freshwater fishes. Our results reveal that with increase in the taxonomic rank, sequence conservation decreases for both nucleotides and amino acids. Order level exhibits lowest conservation with 50% of the nucleotides and amino acids being conserved. Among the variable sites, 30-50% were found to carry high information content within an order, while it was 70-80% within a family and 80-99% within a genus. High information content shows sites with almost conserved sequence but varying at one or two locations, which can be due to variations at species or population level. Thus, the potential of COI gene in higher taxon assignment is revealed with validation of ample inherent signals latent in the gene. PMID:24409929

  1. 78 FR 38851 - Electric Reliability Organization Proposal To Retire Requirements in Reliability Standards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-28

    ... Federal Energy Regulatory Commission 18 CFR Part 40 Electric Reliability Organization Proposal To Retire... Electric Reliability Corporation (NERC), the Commission-certified Electric Reliability Organization. The... 20426, Telephone: (202) 502-6840. Michael Gandolfo (Technical Information), Office of...

  2. Computational methods for efficient structural reliability and reliability sensitivity analysis

    NASA Technical Reports Server (NTRS)

    Wu, Y.-T.

    1993-01-01

    This paper presents recent developments in efficient structural reliability analysis methods. The paper proposes an efficient, adaptive importance sampling (AIS) method that can be used to compute reliability and reliability sensitivities. The AIS approach uses a sampling density that is proportional to the joint PDF of the random variables. Starting from an initial approximate failure domain, sampling proceeds adaptively and incrementally with the goal of reaching a sampling domain that is slightly greater than the failure domain to minimize over-sampling in the safe region. Several reliability sensitivity coefficients are proposed that can be computed directly and easily from the above AIS-based failure points. These probability sensitivities can be used for identifying key random variables and for adjusting design to achieve reliability-based objectives. The proposed AIS methodology is demonstrated using a turbine blade reliability analysis problem.

  3. Reliable vision-guided grasping

    NASA Technical Reports Server (NTRS)

    Nicewarner, Keith E.; Kelley, Robert B.

    1992-01-01

    Automated assembly of truss structures in space requires vision-guided servoing for grasping a strut when its position and orientation are uncertain. This paper presents a methodology for efficient and robust vision-guided robot grasping alignment. The vision-guided grasping problem is related to vision-guided 'docking' problems. It differs from other hand-in-eye visual servoing problems, such as tracking, in that the distance from the target is a relevant servo parameter. The methodology described in this paper is hierarchy of levels in which the vision/robot interface is decreasingly 'intelligent,' and increasingly fast. Speed is achieved primarily by information reduction. This reduction exploits the use of region-of-interest windows in the image plane and feature motion prediction. These reductions invariably require stringent assumptions about the image. Therefore, at a higher level, these assumptions are verified using slower, more reliable methods. This hierarchy provides for robust error recovery in that when a lower-level routine fails, the next-higher routine will be called and so on. A working system is described which visually aligns a robot to grasp a cylindrical strut. The system uses a single camera mounted on the end effector of a robot and requires only crude calibration parameters. The grasping procedure is fast and reliable, with a multi-level error recovery system.

  4. Reliable vision-guided grasping

    NASA Technical Reports Server (NTRS)

    Nicewarner, Keith E.; Kelley, Robert B.

    1992-01-01

    Automated assembly of truss structures in space requires vision-guided servoing for grasping a strut when its position and orientation are uncertain. This paper presents a methodology for efficient and robust vision-guided robot grasping alignment. The vision-guided grasping problem is related to vision-guided 'docking' problems. It differs from other hand-in-eye visual servoing problems such as tracking in that the distance from the target is a relevant servo parameter. The methodology described in this paper is a hierarchy of levels in which the vision/robot interface is decreasingly 'intelligent', and increasingly fast. Speed is achieved primarily by information reduction. This reduction exploits the use of region-of-interest windows in the image plane and feature motion prediction. These reductions invariably require stringent assumptions about the image. Therefore, at a higher level, these assumptions are verified using slower, more reliable methods. This hierarchy provides for robust error recovery in that when a lower-level routine fails, the next-higher routine will be called and so on. A working system is described which visually aligns a robot to grasp a cylindrical strut. The system uses a single camera mounted on the end effector of a robot and requires only crude calibration parameters. The grasping procedure is fast and reliable, with a multi-level error recovery system.

  5. Defining Requirements for Improved Photovoltaic System Reliability

    SciTech Connect

    Maish, A.B.

    1998-12-21

    Reliable systems are an essential ingredient of any technology progressing toward commercial maturity and large-scale deployment. This paper defines reliability as meeting system fictional requirements, and then develops a framework to understand and quantify photovoltaic system reliability based on initial and ongoing costs and system value. The core elements necessary to achieve reliable PV systems are reviewed. These include appropriate system design, satisfactory component reliability, and proper installation and servicing. Reliability status, key issues, and present needs in system reliability are summarized for four application sectors.

  6. The reliability of sensitive information provided by injecting drug users in a clinical setting: clinician-administered versus audio computer-assisted self-interviewing (ACASI).

    PubMed

    Islam, M Mofizul; Topp, Libby; Conigrave, Katherine M; van Beek, Ingrid; Maher, Lisa; White, Ann; Rodgers, Craig; Day, Carolyn A

    2012-01-01

    Research with injecting drug users (IDUs) suggests greater willingness to report sensitive and stigmatised behaviour via audio computer-assisted self-interviewing (ACASI) methods than during face-to-face interviews (FFIs); however, previous studies were limited in verifying this within the same individuals at the same time point. This study examines the relative willingness of IDUs to report sensitive information via ACASI and during a face-to-face clinical assessment administered in health services for IDUs. During recruitment for a randomised controlled trial undertaken at two IDU-targeted health services, assessments were undertaken as per clinical protocols, followed by referral of eligible clients to the trial, in which baseline self-report data were collected via ACASI. Five questions about sensitive injecting and sexual risk behaviours were administered to participants during both clinical interviews and baseline research data collection. "Percentage agreement" determined the magnitude of concordance/discordance in responses across interview methods, while tests appropriate to data format assessed the statistical significance of this variation. Results for all five variables suggest that, relative to ACASI, FFI elicited responses that may be perceived as more socially desirable. Discordance was statistically significant for four of the five variables examined. Participants who reported a history of sex work were more likely to provide discordant responses to at least one socially sensitive item. In health services for IDUs, information collection via ACASI may elicit more reliable and valid responses than FFI. Adoption of a universal precautionary approach to complement individually tailored assessment of and advice regarding health risk behaviours for IDUs may address this issue. PMID:22452446

  7. Photovoltaic module reliability workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986 to 1990. The reliability photovoltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warrantees available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the U.S., PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  8. Photovoltaic module reliability workshop

    SciTech Connect

    Mrig, L.

    1990-01-01

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  9. Use of Sequent Peak Algorithm Drought Severity Index and Hydroclimatic Reconstructions from Tree-Rings to Inform Water Supply Reliability Planning

    NASA Astrophysics Data System (ADS)

    Bray, B. S.; Palhegyi, G.

    2015-12-01

    consistent with Meko et al. (2014) in their analysis of other watersheds in the region. These findings and other insights from the reconstructed runoff timeseries along with the SPADSI provide valuable information for water resource managers evaluating water supply reliability assumptions for future drought planning efforts.

  10. Reliability model of a monopropellant auxiliary propulsion system

    NASA Technical Reports Server (NTRS)

    Greenberg, J. S.

    1971-01-01

    A mathematical model and associated computer code has been developed which computes the reliability of a monopropellant blowdown hydrazine spacecraft auxiliary propulsion system as a function of time. The propulsion system is used to adjust or modify the spacecraft orbit over an extended period of time. The multiple orbit corrections are the multiple objectives which the auxiliary propulsion system is designed to achieve. Thus the reliability model computes the probability of successfully accomplishing each of the desired orbit corrections. To accomplish this, the reliability model interfaces with a computer code that models the performance of a blowdown (unregulated) monopropellant auxiliary propulsion system. The computer code acts as a performance model and as such gives an accurate time history of the system operating parameters. The basic timing and status information is passed on to and utilized by the reliability model which establishes the probability of successfully accomplishing the orbit corrections.

  11. General Achievement Trends: Maryland

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  12. General Achievement Trends: Arkansas

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  13. General Achievement Trends: Idaho

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  14. General Achievement Trends: Nebraska

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  15. General Achievement Trends: Colorado

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  16. General Achievement Trends: Iowa

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  17. General Achievement Trends: Hawaii

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  18. General Achievement Trends: Kentucky

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  19. General Achievement Trends: Florida

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  20. General Achievement Trends: Texas

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  1. General Achievement Trends: Oregon

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  2. General Achievement Trends: Virginia

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  3. Aiming at Achievement.

    ERIC Educational Resources Information Center

    Martinez, Paul

    The Raising Quality and Achievement Program is a 3-year initiative to support further education (FE) colleges in the United Kingdom in their drive to improve students' achievement and the quality of provision. The program offers the following: (1) quality information and advice; (2) onsite support for individual colleges; (3) help with…

  4. General Achievement Trends: Tennessee

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  5. Approach to reliability when applying new technologies

    NASA Technical Reports Server (NTRS)

    Bear, J. C.

    1981-01-01

    Tactical weapon systems, while different in many respects from PTTI applications, face similar risks in achieving reliability in development. General principles derived from experience in achieving high reliability in tactical weapon systems are selectively summarized for application to new technologies in unusual environments.

  6. Reliable VLSI sequential controllers

    NASA Technical Reports Server (NTRS)

    Whitaker, S.; Maki, G.; Shamanna, M.

    1990-01-01

    A VLSI architecture for synchronous sequential controllers is presented that has attractive qualities for producing reliable circuits. In these circuits, one hardware implementation can realize any flow table with a maximum of 2(exp n) internal states and m inputs. Also all design equations are identical. A real time fault detection means is presented along with a strategy for verifying the correctness of the checking hardware. This self check feature can be employed with no increase in hardware. The architecture can be modified to achieve fail safe designs. With no increase in hardware, an adaptable circuit can be realized that allows replacement of faulty transitions with fault free transitions.

  7. CISN Display - Reliable Delivery of Real-time Earthquake Information, Including Rapid Notification and ShakeMap to Critical End Users

    NASA Astrophysics Data System (ADS)

    Rico, H.; Hauksson, E.; Thomas, E.; Friberg, P.; Given, D.

    2002-12-01

    earthquake information on the Web. The links are automatically created when product generators deliver CUBE formatted packets to a Quake Data Distribution System (QDDS) hub (new distribution methods may be used later). The "feeder" modules tap into the QDDS hub and convert the packets into XML-messages. These messages are forwarded to message queues, and then distributed to clients where URLs are dynamically created for these products and linked to events on the CISN Display map. The products may be downloaded out-of-band; and with the inclusion of a GIS mapping tool users can plot organizational assets on the CISN Display map and overlay them against key spectral data, such as ground accelerations. This gives Emergency Response Managers information useful in allocating limited personnel and resources after a major event. At the heart of the system's robustness is a well-established and reliable set of communication protocols for best-effort delivery of data. For critical users a Common Object Request Broker Architecture (CORBA) state-full connection is used via a dedicated signaling channel. The system employs several CORBA methods that alert users of changes in the link status. Loss of connectivity triggers a strategy that attempts to reconnect through various physical and logical paths. Thus, by building on past application successes and proven Internet advances the CISN Display targets a specific audience by providing enhancements previously not available from other applications.

  8. HEPEX - achievements and challenges!

    NASA Astrophysics Data System (ADS)

    Pappenberger, Florian; Ramos, Maria-Helena; Thielen, Jutta; Wood, Andy; Wang, Qj; Duan, Qingyun; Collischonn, Walter; Verkade, Jan; Voisin, Nathalie; Wetterhall, Fredrik; Vuillaume, Jean-Francois Emmanuel; Lucatero Villasenor, Diana; Cloke, Hannah L.; Schaake, John; van Andel, Schalk-Jan

    2014-05-01

    HEPEX is an international initiative bringing together hydrologists, meteorologists, researchers and end-users to develop advanced probabilistic hydrological forecast techniques for improved flood, drought and water management. HEPEX was launched in 2004 as an independent, cooperative international scientific activity. During the first meeting, the overarching goal was defined as: "to develop and test procedures to produce reliable hydrological ensemble forecasts, and to demonstrate their utility in decision making related to the water, environmental and emergency management sectors." The applications of hydrological ensemble predictions span across large spatio-temporal scales, ranging from short-term and localized predictions to global climate change and regional modeling. Within the HEPEX community, information is shared through its blog (www.hepex.org), meetings, testbeds and intercompaison experiments, as well as project reportings. Key questions of HEPEX are: * What adaptations are required for meteorological ensemble systems to be coupled with hydrological ensemble systems? * How should the existing hydrological ensemble prediction systems be modified to account for all sources of uncertainty within a forecast? * What is the best way for the user community to take advantage of ensemble forecasts and to make better decisions based on them? This year HEPEX celebrates its 10th year anniversary and this poster will present a review of the main operational and research achievements and challenges prepared by Hepex contributors on data assimilation, post-processing of hydrologic predictions, forecast verification, communication and use of probabilistic forecasts in decision-making. Additionally, we will present the most recent activities implemented by Hepex and illustrate how everyone can join the community and participate to the development of new approaches in hydrologic ensemble prediction.

  9. Delivery times for caesarean section at Queen Elizabeth Central Hospital, Blantyre, Malawi: is a 30-minute 'informed to start of operative delivery time' achievable?

    PubMed

    O'Regan, M

    2003-08-01

    A timesheet questionnaire was used to assess the time it took from informing the anaesthetist about a case to the start of operative delivery in 78 consecutive patients undergoing caesarean section. Median (IQR [range]) times for grade-1 cases (immediate threat to the life of the mother or fetus) and grade-2 cases (fetal or maternal compromise without immediate threat to life) were 20 (17-35 [6-75]) min and 41 (27-60 [17-136]) min, respectively. Delays occurred in all the component time intervals examined. The primary avoidable delay was the patient's late arrival in theatre. Many significant delays were apparently not perceived by the anaesthetist. In nine (69%) grade-1 cases, the 30-min target decreed by the Association of Anaesthetists of Great Britain & Ireland and the Obstetric Anaesthetists' Association was achieved. PMID:12859467

  10. Reliability and Confidence.

    ERIC Educational Resources Information Center

    Test Service Bulletin, 1952

    1952-01-01

    Some aspects of test reliability are discussed. Topics covered are: (1) how high should a reliability coefficient be?; (2) two factors affecting the interpretation of reliability coefficients--range of talent and interval between testings; (3) some common misconceptions--reliability of speed tests, part vs. total reliability, reliability for what…

  11. Photovoltaic performance and reliability workshop

    SciTech Connect

    Mrig, L.

    1993-12-01

    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986--1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the US, PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  12. Photovoltaic performance and reliability workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    1993-12-01

    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986-1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the U.S., PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  13. Statistical modeling of software reliability

    NASA Technical Reports Server (NTRS)

    Miller, Douglas R.

    1992-01-01

    This working paper discusses the statistical simulation part of a controlled software development experiment being conducted under the direction of the System Validation Methods Branch, Information Systems Division, NASA Langley Research Center. The experiment uses guidance and control software (GCS) aboard a fictitious planetary landing spacecraft: real-time control software operating on a transient mission. Software execution is simulated to study the statistical aspects of reliability and other failure characteristics of the software during development, testing, and random usage. Quantification of software reliability is a major goal. Various reliability concepts are discussed. Experiments are described for performing simulations and collecting appropriate simulated software performance and failure data. This data is then used to make statistical inferences about the quality of the software development and verification processes as well as inferences about the reliability of software versions and reliability growth under random testing and debugging.

  14. Information-seeking Behavior During Residency Is Associated With Quality of Theoretical Learning, Academic Career Achievements, and Evidence-based Medical Practice

    PubMed Central

    Oussalah, Abderrahim; Fournier, Jean-Paul; Guéant, Jean-Louis; Braun, Marc

    2015-01-01

    Abstract Data regarding knowledge acquisition during residency training are sparse. Predictors of theoretical learning quality, academic career achievements and evidence-based medical practice during residency are unknown. We performed a cross-sectional study on residents and attending physicians across several residency programs in 2 French faculties of medicine. We comprehensively evaluated the information-seeking behavior (I-SB) during residency using a standardized questionnaire and looked for independent predictors of theoretical learning quality, academic career achievements, and evidence-based medical practice among I-SB components using multivariate logistic regression analysis. Between February 2013 and May 2013, 338 fellows and attending physicians were included in the study. Textbooks and international medical journals were reported to be used on a regular basis by 24% and 57% of the respondents, respectively. Among the respondents, 47% refer systematically (4.4%) or frequently (42.6%) to published guidelines from scientific societies upon their publication. The median self-reported theoretical learning quality score was 5/10 (interquartile range, 3–6; range, 1–10). A high theoretical learning quality score (upper quartile) was independently and strongly associated with the following I-SB components: systematic reading of clinical guidelines upon their publication (odds ratio [OR], 5.55; 95% confidence interval [CI], 1.77–17.44); having access to a library that offers the leading textbooks of the specialty in the medical department (OR, 2.45, 95% CI, 1.33–4.52); knowledge of the specialty leading textbooks (OR, 2.12; 95% CI, 1.09–4.10); and PubMed search skill score ≥5/10 (OR, 1.94; 95% CI, 1.01–3.73). Research Master (M2) and/or PhD thesis enrolment were independently and strongly associated with the following predictors: PubMed search skill score ≥5/10 (OR, 4.10; 95% CI, 1.46–11.53); knowledge of the leading medical journals of the

  15. Digital Avionics Information System (DAIS): Life Cycle Cost Impact Modeling System Reliability, Maintainability, and Cost Model (RMCM)--Description. Users Guide. Final Report.

    ERIC Educational Resources Information Center

    Goclowski, John C.; And Others

    The Reliability, Maintainability, and Cost Model (RMCM) described in this report is an interactive mathematical model with a built-in sensitivity analysis capability. It is a major component of the Life Cycle Cost Impact Model (LCCIM), which was developed as part of the DAIS advanced development program to be used to assess the potential impacts…

  16. Reliability model generator

    NASA Technical Reports Server (NTRS)

    McMann, Catherine M. (Inventor); Cohen, Gerald C. (Inventor)

    1991-01-01

    An improved method and system for automatically generating reliability models for use with a reliability evaluation tool is described. The reliability model generator of the present invention includes means for storing a plurality of low level reliability models which represent the reliability characteristics for low level system components. In addition, the present invention includes means for defining the interconnection of the low level reliability models via a system architecture description. In accordance with the principles of the present invention, a reliability model for the entire system is automatically generated by aggregating the low level reliability models based on the system architecture description.

  17. Improving Search Engine Reliability

    NASA Astrophysics Data System (ADS)

    Pruthi, Jyoti; Kumar, Ela

    2010-11-01

    Search engines on the Internet are used daily to access and find information. While these services are providing an easy way to find information globally, they are also suffering from artificially created false results. This paper describes two techniques that are being used to manipulate the search engines: spam pages (used to achieve higher rankings on the result page) and cloaking (used to feed falsified data into search engines). This paper also describes two proposed methods to fight this kind of misuse, algorithms for both of the formerly mentioned cases of spamdexing.

  18. An Evaluation of Project Information Packages (PIPs) as Used for the Diffusion of Bilingual Projects. Volume III: A Prototype Guide to Measuring Achievement Level and Program Impact on Achievement in Bilingual Projects.

    ERIC Educational Resources Information Center

    Horst, D. P.; And Others

    This report describes an evaluation of Project Information Packages (PIPs), sets of manuals and other materials intended to help a school district adopt and implement an exemplary education project. Four PIPs were evaluated in a field test, each PIP describing a different bilingual project. It was concluded that the awareness materials produced…

  19. Reliability in the design phase

    SciTech Connect

    Siahpush, A.S.; Hills, S.W.; Pham, H.; Majumdar, D.

    1991-12-01

    A study was performed to determine the common methods and tools that are available to calculated or predict a system`s reliability. A literature review and software survey are included. The desired product of this developmental work is a tool for the system designer to use in the early design phase so that the final design will achieve the desired system reliability without lengthy testing and rework. Three computer programs were written which provide the first attempt at fulfilling this need. The programs are described and a case study is presented for each one. This is a continuing effort which will be furthered in FY-1992. 10 refs.

  20. Reliability in the design phase

    SciTech Connect

    Siahpush, A.S.; Hills, S.W.; Pham, H. ); Majumdar, D. )

    1991-12-01

    A study was performed to determine the common methods and tools that are available to calculated or predict a system's reliability. A literature review and software survey are included. The desired product of this developmental work is a tool for the system designer to use in the early design phase so that the final design will achieve the desired system reliability without lengthy testing and rework. Three computer programs were written which provide the first attempt at fulfilling this need. The programs are described and a case study is presented for each one. This is a continuing effort which will be furthered in FY-1992. 10 refs.

  1. Calculating system reliability with SRFYDO

    SciTech Connect

    Morzinski, Jerome; Anderson - Cook, Christine M; Klamann, Richard M

    2010-01-01

    SRFYDO is a process for estimating reliability of complex systems. Using information from all applicable sources, including full-system (flight) data, component test data, and expert (engineering) judgment, SRFYDO produces reliability estimates and predictions. It is appropriate for series systems with possibly several versions of the system which share some common components. It models reliability as a function of age and up to 2 other lifecycle (usage) covariates. Initial output from its Exploratory Data Analysis mode consists of plots and numerical summaries so that the user can check data entry and model assumptions, and help determine a final form for the system model. The System Reliability mode runs a complete reliability calculation using Bayesian methodology. This mode produces results that estimate reliability at the component, sub-system, and system level. The results include estimates of uncertainty, and can predict reliability at some not-too-distant time in the future. This paper presents an overview of the underlying statistical model for the analysis, discusses model assumptions, and demonstrates usage of SRFYDO.

  2. Advancing Student Achievement

    ERIC Educational Resources Information Center

    Walberg, Herbert J.

    2010-01-01

    For the last half century, higher spending and many modern reforms have failed to raise the achievement of students in the United States to the levels of other economically advanced countries. A possible explanation, says Herbert Walberg, is that much current education theory is ill informed about scientific psychology, often drawing on fads and…

  3. High Reliability and Excellence in Staffing.

    PubMed

    Mensik, Jennifer

    2015-01-01

    Nurse staffing is a complex issue, with many facets and no one right answer. High-reliability organizations (HROs) strive and succeed in achieving a high degree of safety or reliability despite operating in hazardous conditions. HROs have systems in place that make them extremely consistent in accomplishing their goals and avoiding potential errors. However, the inability to resolve quality issues may very well be related to the lack of adoption of high-reliability principles throughout our organizations. PMID:26625582

  4. Reliability analysis in intelligent machines

    NASA Technical Reports Server (NTRS)

    Mcinroy, John E.; Saridis, George N.

    1990-01-01

    Given an explicit task to be executed, an intelligent machine must be able to find the probability of success, or reliability, of alternative control and sensing strategies. By using concepts for information theory and reliability theory, new techniques for finding the reliability corresponding to alternative subsets of control and sensing strategies are proposed such that a desired set of specifications can be satisfied. The analysis is straightforward, provided that a set of Gaussian random state variables is available. An example problem illustrates the technique, and general reliability results are presented for visual servoing with a computed torque-control algorithm. Moreover, the example illustrates the principle of increasing precision with decreasing intelligence at the execution level of an intelligent machine.

  5. Reliability Generalization: "Lapsus Linguae"

    ERIC Educational Resources Information Center

    Smith, Julie M.

    2011-01-01

    This study examines the proposed Reliability Generalization (RG) method for studying reliability. RG employs the application of meta-analytic techniques similar to those used in validity generalization studies to examine reliability coefficients. This study explains why RG does not provide a proper research method for the study of reliability,…

  6. A Study of Secondary Students' Decision-Making Processes with Respect to Information Use, Particularly Students' Judgements of Relevance and Reliability

    ERIC Educational Resources Information Center

    Watson, Curtis L.

    2010-01-01

    This report details an ongoing investigation of the decision-making processes of a group of secondary school students in south-eastern Australia undertaking information search tasks. The study is situated in the field of information seeking and use, and, more broadly, in decision making. Research questions focus on students' decisions about the…

  7. Characterizing reliability in a product/process design-assurance program

    SciTech Connect

    Kerscher, W.J. III; Booker, J.M.; Bement, T.R.; Meyer, M.A.

    1997-10-01

    Over the years many advancing techniques in the area of reliability engineering have surfaced in the military sphere of influence, and one of these techniques is Reliability Growth Testing (RGT). Private industry has reviewed RGT as part of the solution to their reliability concerns, but many practical considerations have slowed its implementation. It`s objective is to demonstrate the reliability requirement of a new product with a specified confidence. This paper speaks directly to that objective but discusses a somewhat different approach to achieving it. Rather than conducting testing as a continuum and developing statistical confidence bands around the results, this Bayesian updating approach starts with a reliability estimate characterized by large uncertainty and then proceeds to reduce the uncertainty by folding in fresh information in a Bayesian framework.

  8. Epistemological Beliefs and Academic Achievement

    ERIC Educational Resources Information Center

    Arslantas, Halis Adnan

    2016-01-01

    This study aimed to identify the relationship between teacher candidates' epistemological beliefs and academic achievement. The participants of the study were 353 teacher candidates studying their fourth year at the Education Faculty. The Epistemological Belief Scale was used which adapted to Turkish through reliability and validity work by…

  9. Can There Be Reliability without "Reliability?"

    ERIC Educational Resources Information Center

    Mislevy, Robert J.

    2004-01-01

    An "Educational Researcher" article by Pamela Moss (1994) asks the title question, "Can there be validity without reliability?" Yes, she answers, if by reliability one means "consistency among independent observations intended as interchangeable" (Moss, 1994, p. 7), quantified by internal consistency indices such as KR-20 coefficients and…

  10. The effects of geographic information system (GIS) technologies on students' attitudes, self-efficacy, and achievement in middle school science classrooms

    NASA Astrophysics Data System (ADS)

    Baker, Thomas Ray

    Since the publication of the National Science Education Standards , a concerted and evolving movement to make science classrooms more inquiry-oriented has been building. The proliferation of models of teaching and learning where questions and investigations drive learning, while not new are also not easy to plan, implement, or evaluate. In order to make the vision of the Standards come to fruition, educators are calling on the tools of technology to support and foster the shift to scientific inquiry or classroom research. The use of certain data analysis technologies have been suggested to be a particularly powerful ally in the struggle to extend classroom teaching and learning into the realm of problem-driven classroom inquiry. The use of a Geographic Information System (GIS), a technology allowing for the graphical representation of data with a geographic component seems to be one technology that can adequately bolster the dynamic and complex needs of the science classroom engaged in scientific inquiry. In this study, eighth grade Earth science students studying relative, local air quality indicators were divided in two groups; a treatment group that utilized GIS-supported scientific inquiry and a control group that used traditional mapping techniques to support their study. Student attitudes regarding science and technology were measured with a pre/post instrument across the study. Individual student efforts were summarily evaluated with a modified Kansas Science Performance Based Assessment rubric. During the two-week treatment, the students using the GIS-supported materials were found to show positive and significant improvements in science self-efficacy and attitudes toward technology. While female attitudes and self-efficacy were not found to change, males significantly improved on all affective factors. Students using GIS also performed significantly better than traditional mapping students on science process skills, specifically data analysis techniques

  11. New Information Dispersal Techniques for Trustworthy Computing

    ERIC Educational Resources Information Center

    Parakh, Abhishek

    2011-01-01

    Information dispersal algorithms (IDA) are used for distributed data storage because they simultaneously provide security, reliability and space efficiency, constituting a trustworthy computing framework for many critical applications, such as cloud computing, in the information society. In the most general sense, this is achieved by dividing data…

  12. Reliability computation from reliability block diagrams

    NASA Technical Reports Server (NTRS)

    Chelson, P. O.; Eckstein, R. E.

    1971-01-01

    A method and a computer program are presented to calculate probability of system success from an arbitrary reliability block diagram. The class of reliability block diagrams that can be handled include any active/standby combination of redundancy, and the computations include the effects of dormancy and switching in any standby redundancy. The mechanics of the program are based on an extension of the probability tree method of computing system probabilities.

  13. Power electronics reliability analysis.

    SciTech Connect

    Smith, Mark A.; Atcitty, Stanley

    2009-12-01

    This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Analysis of a fictitious device demonstrates the latter process. Optimization can use the resulting baseline model to decide how to improve reliability and/or lower costs. It is recommended that both electric utilities and equipment manufacturers make provisions to collect and share data in order to lay the groundwork for improving reliability into the future. Reliability analysis helps guide reliability improvements in hardware and software technology including condition monitoring and prognostics and health management.

  14. Human Reliability Program Overview

    SciTech Connect

    Bodin, Michael

    2012-09-25

    This presentation covers the high points of the Human Reliability Program, including certification/decertification, critical positions, due process, organizational structure, program components, personnel security, an overview of the US DOE reliability program, retirees and academia, and security program integration.

  15. Advanced reactor instrumentation and control reliability and risk assessment

    SciTech Connect

    Fullwood, R.; Gunther, W.; Valente, J.; Azarm, M.A.

    1991-01-01

    Advanced nuclear power reactors will used different approaches to achieving a higher level of safety than the first generation. One approach used the technological developments in computation and electronics in the form of digital instrumentation and control (I C) to enhance the reliability, and accuracy of information for plant control, responding to the information, and controlling the plant and its systems under normal and upset environments in various states of degradation. Evaluating the reliability and safety of advanced I C systems requires determining the reliability of the I C used in the advanced reactors which involves distributed processing, data pile-up, interactive systems, the man-machine interface, various forms of automatic control, and systems interactions. From these analyses will come an understanding of the potential of the new I C, and protection from its vulnerabilities to enhance the safe operation of the new plants. Technological, safety, reliability, and regulatory issues associated with advanced I C for the new reactors are discussed herein. The issues are presented followed by suggested approaches to their resolution.

  16. Advanced reactor instrumentation and control reliability and risk assessment

    SciTech Connect

    Fullwood, R.; Gunther, W.; Valente, J.; Azarm, M.A.

    1991-12-31

    Advanced nuclear power reactors will used different approaches to achieving a higher level of safety than the first generation. One approach used the technological developments in computation and electronics in the form of digital instrumentation and control (I&C) to enhance the reliability, and accuracy of information for plant control, responding to the information, and controlling the plant and its systems under normal and upset environments in various states of degradation. Evaluating the reliability and safety of advanced I&C systems requires determining the reliability of the I&C used in the advanced reactors which involves distributed processing, data pile-up, interactive systems, the man-machine interface, various forms of automatic control, and systems interactions. From these analyses will come an understanding of the potential of the new I&C, and protection from its vulnerabilities to enhance the safe operation of the new plants. Technological, safety, reliability, and regulatory issues associated with advanced I&C for the new reactors are discussed herein. The issues are presented followed by suggested approaches to their resolution.

  17. Reliable Design Versus Trust

    NASA Technical Reports Server (NTRS)

    Berg, Melanie; LaBel, Kenneth A.

    2016-01-01

    This presentation focuses on reliability and trust for the users portion of the FPGA design flow. It is assumed that the manufacturer prior to hand-off to the user tests FPGA internal components. The objective is to present the challenges of creating reliable and trusted designs. The following will be addressed: What makes a design vulnerable to functional flaws (reliability) or attackers (trust)? What are the challenges for verifying a reliable design versus a trusted design?

  18. Basic Achievement Skills Individual Screener (BASIS).

    ERIC Educational Resources Information Center

    Ysseldyke, James E.

    1985-01-01

    Reviews the behaviors sampled, test administration, scoring, norms, reliability, and validity of the Basic Achievement Skills Individual Screener (BASIS), an individually administered test that measures skill development in reading, mathematics, spelling, and writing. (BL)

  19. Human Capital: Building the Information Technology Workforce To Achieve Results. Testimony before the Subcommittee on Technology and Procurement Policy, Committee on Government Reform, U.S. House of Representatives.

    ERIC Educational Resources Information Center

    Walker, David M.

    The Comptroller General of the United States testified before Congress regarding the General Accounting Office's (GAO's) framework for building the information technology (IT) work force to achieve results. The following were among the key points of his testimony: (1) the federal government is facing pervasive human capital challenges that are…

  20. Predicting software reliability

    NASA Technical Reports Server (NTRS)

    Littlewood, B.

    1989-01-01

    A detailed look is given to software reliability techniques. A conceptual model of the failure process is examined, and some software reliability growth models are discussed. Problems for which no current solutions exist are addressed, emphasizing the very difficult problem of safety-critical systems for which the reliability requirements can be enormously demanding.

  1. Reliability model generator specification

    NASA Technical Reports Server (NTRS)

    Cohen, Gerald C.; Mccann, Catherine

    1990-01-01

    The Reliability Model Generator (RMG), a program which produces reliability models from block diagrams for ASSIST, the interface for the reliability evaluation tool SURE is described. An account is given of motivation for RMG and the implemented algorithms are discussed. The appendices contain the algorithms and two detailed traces of examples.

  2. Reliability assurance for regulation of advanced reactors

    SciTech Connect

    Fullwood, R.; Lofaro, R.; Samanta, P.

    1991-01-01

    The advanced nuclear power plants must achieve higher levels of safety than the first generation of plants. Showing that this is indeed true provides new challenges to reliability and risk assessment methods in the analysis of the designs employing passive and semi-passive protection. Reliability assurance of the advanced reactor systems is important for determining the safety of the design and for determining the plant operability. Safety is the primary concern, but operability is considered indicative of good and safe operation. This paper discusses several concerns for reliability assurance of the advanced design encompassing reliability determination, level of detail required in advanced reactor submittals, data for reliability assurance, systems interactions and common cause effects, passive component reliability, PRA-based configuration control system, and inspection, training, maintenance and test requirements. Suggested approaches are provided for addressing each of these topics.

  3. Reliability assurance for regulation of advanced reactors

    SciTech Connect

    Fullwood, R.; Lofaro, R.; Samanta, P.

    1991-12-31

    The advanced nuclear power plants must achieve higher levels of safety than the first generation of plants. Showing that this is indeed true provides new challenges to reliability and risk assessment methods in the analysis of the designs employing passive and semi-passive protection. Reliability assurance of the advanced reactor systems is important for determining the safety of the design and for determining the plant operability. Safety is the primary concern, but operability is considered indicative of good and safe operation. This paper discusses several concerns for reliability assurance of the advanced design encompassing reliability determination, level of detail required in advanced reactor submittals, data for reliability assurance, systems interactions and common cause effects, passive component reliability, PRA-based configuration control system, and inspection, training, maintenance and test requirements. Suggested approaches are provided for addressing each of these topics.

  4. An asymptotic approach for assessing fatigue reliability

    SciTech Connect

    Tang, J.

    1996-12-01

    By applying the cumulative fatigue damage theory to the random process reliability problem, and the introduction of a new concept of unified equivalent stress level in fatigue life prediction, a technical reliability model for the random process reliability problem under fatigue failure is proposed. The technical model emphasizes efficiency in the design choice and also focuses on the accuracy of the results. Based on this model, an asymptotic method for fatigue reliability under stochastic process loadings is developed. The proposed method uses the recursive iteration algorithm to achieve results which include reliability and corresponding life. The method reconciles the requirement of accuracy and efficiency for the random process reliability problems under fatigue failure. The accuracy and analytical and numerical efforts required are compared. Through numerical example, the advantage of the proposed method is demonstrated.

  5. Reliable timing systems for computer controlled accelerators

    NASA Astrophysics Data System (ADS)

    Knott, Jürgen; Nettleton, Robert

    1986-06-01

    Over the past decade the use of computers has set new standards for control systems of accelerators with ever increasing complexity coupled with stringent reliability criteria. In fact, with very slow cycling machines or storage rings any erratic operation or timing pulse will cause the loss of precious particles and waste hours of time and effort of preparation. Thus, for the CERN linac and LEAR (Low Energy Antiproton Ring) timing system reliability becomes a crucial factor in the sense that all components must operate practically without fault for very long periods compared to the effective machine cycle. This has been achieved by careful selection of components and design well below thermal and electrical limits, using error detection and correction where possible, as well as developing "safe" decoding techniques for serial data trains. Further, consistent structuring had to be applied in order to obtain simple and flexible modular configurations with very few components on critical paths and to minimize the exchange of information to synchronize accelerators. In addition, this structuring allows the development of efficient strategies for on-line and off-line fault diagnostics. As a result, the timing system for Linac 2 has, so far, been operating without fault for three years, the one for LEAR more than one year since its final debugging.

  6. Human Reliability Analysis for Design: Using Reliability Methods for Human Factors Issues

    SciTech Connect

    Ronald Laurids Boring

    2010-11-01

    This paper reviews the application of human reliability analysis methods to human factors design issues. An application framework is sketched in which aspects of modeling typically found in human reliability analysis are used in a complementary fashion to the existing human factors phases of design and testing. The paper provides best achievable practices for design, testing, and modeling. Such best achievable practices may be used to evaluate and human system interface in the context of design safety certifications.

  7. Decision-making and response strategies in interaction with alarms: the impact of alarm reliability, availability of alarm validity information and workload.

    PubMed

    Manzey, Dietrich; Gérard, Nina; Wiczorek, Rebecca

    2014-01-01

    Responding to alarm systems which usually commit a number of false alarms and/or misses involves decision-making under uncertainty. Four laboratory experiments including a total of 256 participants were conducted to gain comprehensive insight into humans' dealing with this uncertainty. Specifically, it was investigated how responses to alarms/non-alarms are affected by the predictive validities of these events, and to what extent response strategies depend on whether or not the validity of alarms/non-alarms can be cross-checked against other data. Among others, the results suggest that, without cross-check possibility (experiment 1), low levels of predictive validity of alarms ( ≤ 0.5) led most participants to use one of two different strategies which both involved non-responding to a significant number of alarms (cry-wolf effect). Yet, providing access to alarm validity information reduced this effect dramatically (experiment 2). This latter result emerged independent of the effort needed for cross-checkings of alarms (experiment 3), but was affected by the workload imposed by concurrent tasks (experiment 4). Theoretical and practical consequences of these results for decision-making and response selection in interaction with alarm systems, as well as the design of effective alarm systems, are discussed. PMID:25224606

  8. General Achievement Trends: South Dakota

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  9. General Achievement Trends: New Jersey

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  10. General Achievement Trends: North Carolina

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  11. Human reliability analysis

    SciTech Connect

    Dougherty, E.M.; Fragola, J.R.

    1988-01-01

    The authors present a treatment of human reliability analysis incorporating an introduction to probabilistic risk assessment for nuclear power generating stations. They treat the subject according to the framework established for general systems theory. Draws upon reliability analysis, psychology, human factors engineering, and statistics, integrating elements of these fields within a systems framework. Provides a history of human reliability analysis, and includes examples of the application of the systems approach.

  12. Model VESL Program Guide, Office Information Systems, International: One Semester Intensive Training Certificate of Achievement Programs in General, Medical, and Legal Office.

    ERIC Educational Resources Information Center

    Alvarez, Irma J.

    The Office Information Systems-International Program at Southwestern College, in California, was designed to provide Hispanic students with training for entry-level office employment. This model program guide stems from a project to improve curricula and delivery and focuses on changes in three intensive bilingual programs in general, medical, and…

  13. Building a Rapid Learning Health Care System for Oncology: Why CancerLinQ Collects Identifiable Health Information to Achieve Its Vision.

    PubMed

    Shah, Alaap; Stewart, Andrew K; Kolacevski, Andrej; Michels, Dina; Miller, Robert

    2016-03-01

    The ever-increasing volume of scientific discoveries, clinical knowledge, novel diagnostic tools, and treatment options juxtaposed with rising costs in health care challenge physicians to identify, prioritize, and use new information rapidly to deliver efficient and high-quality care to a growing and aging patient population. CancerLinQ, a rapid learning health care system in oncology, is an initiative of the American Society of Clinical Oncology and its Institute for Quality that addresses these challenges by collecting information from the electronic health records of large numbers of patients with cancer. CancerLinQ is first and foremost a quality measurement and reporting system through which oncologists can harness the depth and power of their patients' clinical records and other data to assess, monitor, and improve the care they deliver. However, in light of privacy and security concerns with regard to collection, use, and disclosure of patient information, this article addresses the need to collect protected health information as defined under the Health Insurance Portability and Accountability Act of 1996 to drive rapid learning through CancerLinQ. PMID:26755519

  14. Recalibrating software reliability models

    NASA Technical Reports Server (NTRS)

    Brocklehurst, Sarah; Chan, P. Y.; Littlewood, Bev; Snell, John

    1989-01-01

    In spite of much research effort, there is no universally applicable software reliability growth model which can be trusted to give accurate predictions of reliability in all circumstances. Further, it is not even possible to decide a priori which of the many models is most suitable in a particular context. In an attempt to resolve this problem, techniques were developed whereby, for each program, the accuracy of various models can be analyzed. A user is thus enabled to select that model which is giving the most accurate reliability predictions for the particular program under examination. One of these ways of analyzing predictive accuracy, called the u-plot, in fact allows a user to estimate the relationship between the predicted reliability and the true reliability. It is shown how this can be used to improve reliability predictions in a completely general way by a process of recalibration. Simulation results show that the technique gives improved reliability predictions in a large proportion of cases. However, a user does not need to trust the efficacy of recalibration, since the new reliability estimates produced by the technique are truly predictive and so their accuracy in a particular application can be judged using the earlier methods. The generality of this approach would therefore suggest that it be applied as a matter of course whenever a software reliability model is used.

  15. Software Reliability 2002

    NASA Technical Reports Server (NTRS)

    Wallace, Dolores R.

    2003-01-01

    In FY01 we learned that hardware reliability models need substantial changes to account for differences in software, thus making software reliability measurements more effective, accurate, and easier to apply. These reliability models are generally based on familiar distributions or parametric methods. An obvious question is 'What new statistical and probability models can be developed using non-parametric and distribution-free methods instead of the traditional parametric method?" Two approaches to software reliability engineering appear somewhat promising. The first study, begin in FY01, is based in hardware reliability, a very well established science that has many aspects that can be applied to software. This research effort has investigated mathematical aspects of hardware reliability and has identified those applicable to software. Currently the research effort is applying and testing these approaches to software reliability measurement, These parametric models require much project data that may be difficult to apply and interpret. Projects at GSFC are often complex in both technology and schedules. Assessing and estimating reliability of the final system is extremely difficult when various subsystems are tested and completed long before others. Parametric and distribution free techniques may offer a new and accurate way of modeling failure time and other project data to provide earlier and more accurate estimates of system reliability.

  16. Recalibrating software reliability models

    NASA Technical Reports Server (NTRS)

    Brocklehurst, Sarah; Chan, P. Y.; Littlewood, Bev; Snell, John

    1990-01-01

    In spite of much research effort, there is no universally applicable software reliability growth model which can be trusted to give accurate predictions of reliability in all circumstances. Further, it is not even possible to decide a priori which of the many models is most suitable in a particular context. In an attempt to resolve this problem, techniques were developed whereby, for each program, the accuracy of various models can be analyzed. A user is thus enabled to select that model which is giving the most accurate reliability predicitons for the particular program under examination. One of these ways of analyzing predictive accuracy, called the u-plot, in fact allows a user to estimate the relationship between the predicted reliability and the true reliability. It is shown how this can be used to improve reliability predictions in a completely general way by a process of recalibration. Simulation results show that the technique gives improved reliability predictions in a large proportion of cases. However, a user does not need to trust the efficacy of recalibration, since the new reliability estimates prodcued by the technique are truly predictive and so their accuracy in a particular application can be judged using the earlier methods. The generality of this approach would therefore suggest that it be applied as a matter of course whenever a software reliability model is used.

  17. Reliability of fluid systems

    NASA Astrophysics Data System (ADS)

    Kopáček, Jaroslav; Fojtášek, Kamil; Dvořák, Lukáš

    2016-03-01

    This paper focuses on the importance of detection reliability, especially in complex fluid systems for demanding production technology. The initial criterion for assessing the reliability is the failure of object (element), which is seen as a random variable and their data (values) can be processed using by the mathematical methods of theory probability and statistics. They are defined the basic indicators of reliability and their applications in calculations of serial, parallel and backed-up systems. For illustration, there are calculation examples of indicators of reliability for various elements of the system and for the selected pneumatic circuit.

  18. Gearbox Reliability Collaborative (GRC) Description and Loading

    SciTech Connect

    Oyague, F.

    2011-11-01

    This document describes simulated turbine load cases in accordance to the IEC 61400-1 Ed.3 standard, which is representative of the typical wind turbine design process. The information presented herein is intended to provide a broad understanding of the gearbox reliability collaborative 750kW drivetrain and turbine configuration. In addition, fatigue and ultimate strength drivetrain loads resulting from simulations are presented. This information provides the bases for the analytical work of the gearbox reliability collaborative effort.

  19. Six Motivational Reasons for Low School Achievement

    ERIC Educational Resources Information Center

    Reiss, Steven

    2009-01-01

    Reiss ("The normal personality: a new way of thinking about people." Cambridge University Press, New York, 2008) empirically derived a reliable and valid taxonomy of 16 life motives ("psychological needs"). The model suggests six motivational reasons for low achievement in school. Low achievement may be motivated by fear of failure (high need for…

  20. Understanding Reliability: A Review for Veterinary Educators.

    PubMed

    Royal, Kenneth D; Hecker, Kent G

    2016-01-01

    Veterinary medical faculty and administrators routinely administer student assessments and conduct surveys to make decisions regarding student performance and to assess their courses/curricula. The decisions that are made are a result of the scores generated. However, how reliable are the scores and how confident can we be about these decisions? Reliability is one of the hallmarks of validity evidence, but what does this mean and what affects the reliability of scores? The purpose of this article is to provide veterinary medical educators and administrators with fundamental information regarding the concept of reliability. Specifically, we review what sources of error reduce the reliability of scores and we describe the different types of reliability coefficients that are reported. PMID:26560547

  1. Relating design and environmental variables to reliability

    NASA Astrophysics Data System (ADS)

    Kolarik, William J.; Landers, Thomas L.

    The combination of space application and nuclear power source demands high reliability hardware. The possibilities of failure, either an inability to provide power or a catastrophic accident, must be minimized. Nuclear power experiences on the ground have led to highly sophisticated probabilistic risk assessment procedures, most of which require quantitative information to adequately assess such risks. In the area of hardware risk analysis, reliability information plays a key role. One of the lessons learned from the Three Mile Island experience is that thorough analyses of critical components are essential. Nuclear grade equipment shows some reliability advantages over commercial. However, no statistically significant difference has been found. A recent study pertaining to spacecraft electronics reliability, examined some 2500 malfunctions on more than 300 aircraft. The study classified the equipment failures into seven general categories. Design deficiencies and lack of environmental protection accounted for about half of all failures. Within each class, limited reliability modeling was performed using a Weibull failure model.

  2. Effect of ethnicity, gender and drug use history on achieving high rates of affirmative informed consent for genetics research: impact of sharing with a national repository

    PubMed Central

    Ray, Brenda; Jackson, Colin; Ducat, Elizabeth; Ho, Ann; Hamon, Sara; Kreek, Mary Jeanne

    2013-01-01

    Aim Genetic research representative of the population is crucial to understanding the underlying causes of many diseases. In a prospective evaluation of informed consent we assessed the willingness of individuals of different ethnicities, gender and drug dependence history to participate in genetic studies in which their genetic sample could be shared with a repository at the National Institutes of Health. Methods Potential subjects were recruited from the general population through the use of flyers and referrals from previous participants and clinicians with knowledge of our study. They could consent to 11 separate choices so that they could specify how and with whom their genetic sample could be shared. Rates of affirmative consent were then analysed by gender, ethnicity and drug dependence history. Results Of 1416 volunteers enrolled, 99.7% gave affirmative informed consent for studies of addiction conducted in our laboratory. No significant difference was found for participation in genetic studies conducted in our laboratory by gender, ethnicity or drug dependence history. Over all 11 questions, individuals with a history of drug use were more likely to agree to consent to participate in our study than were healthy volunteers. Conclusion A high percentage of each category of gender, ethnicity and drug history, gave affirmative consent at all levels. The level of detail in and the amount of time spent reviewing the informed consent, and a relationship of trust with the clinical investigator may contribute to this outcome. PMID:21266386

  3. Reliability-based casing design

    SciTech Connect

    Maes, M.A.; Gulati, K.C.; Johnson, R.C.; McKenna, D.L.; Brand, P.R.; Lewis, D.B.

    1995-06-01

    The present paper describes the development of reliability-based design criteria for oil and/or gas well casing/tubing. The approach is based on the fundamental principles of limit state design. Limit states for tubulars are discussed and specific techniques for the stochastic modeling of loading and resistance variables are described. Zonation methods and calibration techniques are developed which are geared specifically to the characteristic tubular design for both hydrocarbon drilling and production applications. The application of quantitative risk analysis to the development of risk-consistent design criteria is shown to be a major and necessary step forward in achieving more economic tubular design.

  4. Hawaii electric system reliability.

    SciTech Connect

    Silva Monroy, Cesar Augusto; Loose, Verne William

    2012-09-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  5. Graded Achievement, Tested Achievement, and Validity

    ERIC Educational Resources Information Center

    Brookhart, Susan M.

    2015-01-01

    Twenty-eight studies of grades, over a century, were reviewed using the argument-based approach to validity suggested by Kane as a theoretical framework. The review draws conclusions about the meaning of graded achievement, its relation to tested achievement, and changes in the construct of graded achievement over time. "Graded…

  6. Reliability improvements on Thales RM2 rotary Stirling coolers: analysis and methodology

    NASA Astrophysics Data System (ADS)

    Cauquil, J. M.; Seguineau, C.; Martin, J.-Y.; Benschop, T.

    2016-05-01

    The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. The cooler reliability is thus one of its most important parameters. This parameter has to increase to answer market needs. To do this, the data for identifying the weakest element determining cooler reliability has to be collected. Yet, data collection based on field are hardly usable due to lack of informations. A method for identifying the improvement in reliability has then to be set up which can be used even without field return. This paper will describe the method followed by Thales Cryogénie SAS to reach such a result. First, a database was built from extensive expertizes of RM2 failures occurring in accelerate ageing. Failure modes have then been identified and corrective actions achieved. Besides this, a hierarchical organization of the functions of the cooler has been done with regard to the potential increase of its efficiency. Specific changes have been introduced on the functions most likely to impact efficiency. The link between efficiency and reliability will be described in this paper. The work on the two axes - weak spots for cooler reliability and efficiency - permitted us to increase in a drastic way the MTTF of the RM2 cooler. Huge improvements in RM2 reliability are actually proven by both field return and reliability monitoring. These figures will be discussed in the paper.

  7. Photovoltaic system reliability

    SciTech Connect

    Maish, A.B.; Atcitty, C.; Greenberg, D.

    1997-10-01

    This paper discusses the reliability of several photovoltaic projects including SMUD`s PV Pioneer project, various projects monitored by Ascension Technology, and the Colorado Parks project. System times-to-failure range from 1 to 16 years, and maintenance costs range from 1 to 16 cents per kilowatt-hour. Factors contributing to the reliability of these systems are discussed, and practices are recommended that can be applied to future projects. This paper also discusses the methodology used to collect and analyze PV system reliability data.

  8. Closing the Achievement Gap: Challenges and Opportunities

    ERIC Educational Resources Information Center

    Robards, Shirley N.

    2008-01-01

    Closing the achievement gap between low- and high-achieving public school students is an important goal of public education. This article explores background information and research and discusses examples of best practices to close the achievement gap. Several plans have been proposed as ways to enhance the achievement of under-represented…

  9. Software reliability studies

    NASA Technical Reports Server (NTRS)

    Wilson, Larry W.

    1989-01-01

    The longterm goal of this research is to identify or create a model for use in analyzing the reliability of flight control software. The immediate tasks addressed are the creation of data useful to the study of software reliability and production of results pertinent to software reliability through the analysis of existing reliability models and data. The completed data creation portion of this research consists of a Generic Checkout System (GCS) design document created in cooperation with NASA and Research Triangle Institute (RTI) experimenters. This will lead to design and code reviews with the resulting product being one of the versions used in the Terminal Descent Experiment being conducted by the Systems Validations Methods Branch (SVMB) of NASA/Langley. An appended paper details an investigation of the Jelinski-Moranda and Geometric models for software reliability. The models were given data from a process that they have correctly simulated and asked to make predictions about the reliability of that process. It was found that either model will usually fail to make good predictions. These problems were attributed to randomness in the data and replication of data was recommended.

  10. A Reliability Induction and Reliability Generalization Study of the Cage Questionnaire

    ERIC Educational Resources Information Center

    Shields, Alan L.; Caruso, John C.

    2004-01-01

    The CAGE is a commonly used alcohol screening instrument. Although considerable work has been done on the validity of CAGE scores, relatively little information is available on their reliability. Reliability induction and generalization studies were performed for the CAGE. Of the 259 studies available for analysis, only 19 (7.3%) contained…

  11. Mission Reliability Estimation for Repairable Robot Teams

    NASA Technical Reports Server (NTRS)

    Trebi-Ollennu, Ashitey; Dolan, John; Stancliff, Stephen

    2010-01-01

    A mission reliability estimation method has been designed to translate mission requirements into choices of robot modules in order to configure a multi-robot team to have high reliability at minimal cost. In order to build cost-effective robot teams for long-term missions, one must be able to compare alternative design paradigms in a principled way by comparing the reliability of different robot models and robot team configurations. Core modules have been created including: a probabilistic module with reliability-cost characteristics, a method for combining the characteristics of multiple modules to determine an overall reliability-cost characteristic, and a method for the generation of legitimate module combinations based on mission specifications and the selection of the best of the resulting combinations from a cost-reliability standpoint. The developed methodology can be used to predict the probability of a mission being completed, given information about the components used to build the robots, as well as information about the mission tasks. In the research for this innovation, sample robot missions were examined and compared to the performance of robot teams with different numbers of robots and different numbers of spare components. Data that a mission designer would need was factored in, such as whether it would be better to have a spare robot versus an equivalent number of spare parts, or if mission cost can be reduced while maintaining reliability using spares. This analytical model was applied to an example robot mission, examining the cost-reliability tradeoffs among different team configurations. Particularly scrutinized were teams using either redundancy (spare robots) or repairability (spare components). Using conservative estimates of the cost-reliability relationship, results show that it is possible to significantly reduce the cost of a robotic mission by using cheaper, lower-reliability components and providing spares. This suggests that the

  12. MOV reliability evaluation and periodic verification scheduling

    SciTech Connect

    Bunte, B.D.

    1996-12-01

    The purpose of this paper is to establish a periodic verification testing schedule based on the expected long term reliability of gate or globe motor operated valves (MOVs). The methodology in this position paper determines the nominal (best estimate) design margin for any MOV based on the best available information pertaining to the MOVs design requirements, design parameters, existing hardware design, and present setup. The uncertainty in this margin is then determined using statistical means. By comparing the nominal margin to the uncertainty, the reliability of the MOV is estimated. The methodology is appropriate for evaluating the reliability of MOVs in the GL 89-10 program. It may be used following periodic testing to evaluate and trend MOV performance and reliability. It may also be used to evaluate the impact of proposed modifications and maintenance activities such as packing adjustments. In addition, it may be used to assess the impact of new information of a generic nature which impacts safety related MOVs.

  13. Estimating the Reliability of a Crewed Spacecraft

    NASA Astrophysics Data System (ADS)

    Lutomski, M. G.; Garza, J.

    2012-01-01

    Now that the Space Shuttle Program has been retired, the Russian Soyuz Launcher and Soyuz Spacecraft are the only means for crew transportation to and from the International Space Station (ISS). Are the astronauts and cosmonauts safer on the Soyuz than the Space Shuttle system? How do you estimate the reliability of such a crewed spacecraft? The recent loss of the 44 Progress resupply flight to the ISS has put these questions front and center. The Soyuz launcher has been in operation for over 40 years. There have been only two Loss of Crew (LOC) incidents and two Loss of Mission (LOM) incidents involving crew missions. Given that the most recent crewed Soyuz launcher incident took place in 1983, how do we determine current reliability of such a system? How do all of the failures of unmanned Soyuz family launchers such as the 44P impact the reliability of the currently operational crewed launcher? Does the Soyuz exhibit characteristics that demonstrate reliability growth and how would that be reflected in future estimates of success? In addition NASA has begun development of the Orion or Multi-Purpose Crewed Vehicle as well as started an initiative to purchase Commercial Crew services from private firms. The reliability targets are currently several times higher than the last Shuttle reliability estimate. Can these targets be compared to the reliability of the Soyuz arguably the highest reliable crewed spacecraft and launcher in the world to determine whether they are realistic and achievable? To help answer these questions this paper will explore how to estimate the reliability of the Soyuz launcher/spacecraft system over its mission to give a benchmark for other human spaceflight vehicles and their missions. Specifically this paper will look at estimating the Loss of Mission (LOM) and Loss of Crew (LOC) probability for an ISS crewed Soyuz launcher/spacecraft mission using historical data, reliability growth, and Probabilistic Risk Assessment (PRA) techniques.

  14. Flight control electronics reliability/maintenance study

    NASA Technical Reports Server (NTRS)

    Dade, W. W.; Edwards, R. H.; Katt, G. T.; Mcclellan, K. L.; Shomber, H. A.

    1977-01-01

    Collection and analysis of data are reported that concern the reliability and maintenance experience of flight control system electronics currently in use on passenger carrying jet aircraft. Two airlines B-747 airplane fleets were analyzed to assess the component reliability, system functional reliability, and achieved availability of the CAT II configuration flight control system. Also assessed were the costs generated by this system in the categories of spare equipment, schedule irregularity, and line and shop maintenance. The results indicate that although there is a marked difference in the geographic location and route pattern between the airlines studied, there is a close similarity in the reliability and the maintenance costs associated with the flight control electronics.

  15. A model for managing the cost of reliability

    NASA Astrophysics Data System (ADS)

    Sears, Raymond W., Jr.

    A parametric model which estimates the distribution of effort expended in the achievement of reliability during the various phases of product development has been formulated, with a view to the maximization of return on reliability investment. The model equations and their associated minimization criteria have been programmed on a PC to allow the examination of the effects of varying parameters on the development process and the reliability-achievement strategy, as well as to allow the calibration of modeling parameters against cost and reliability data obtained by various development programs. Model calibration accommodates numerous plausible scenarios of product development.

  16. Recognizing outstanding achievements

    NASA Astrophysics Data System (ADS)

    Speiss, Fred

    One function of any professional society is to provide an objective, informed means for recognizing outstanding achievements in its field. In AGU's Ocean Sciences section we have a variety of means for carrying out this duty. They include recognition of outstanding student presentations at our meetings, dedication of special sessions, nomination of individuals to be fellows of the Union, invitations to present Sverdrup lectures, and recommendations for Macelwane Medals, the Ocean Sciences Award, and the Ewing Medal.Since the decision to bestow these awards requires initiative and judgement by members of our section in addition to a deserving individual, it seems appropriate to review the selection process for each and to urge you to identify those deserving of recognition.

  17. Statistical modelling of software reliability

    NASA Technical Reports Server (NTRS)

    Miller, Douglas R.

    1991-01-01

    During the six-month period from 1 April 1991 to 30 September 1991 the following research papers in statistical modeling of software reliability appeared: (1) A Nonparametric Software Reliability Growth Model; (2) On the Use and the Performance of Software Reliability Growth Models; (3) Research and Development Issues in Software Reliability Engineering; (4) Special Issues on Software; and (5) Software Reliability and Safety.

  18. Photovoltaic Module Reliability Workshop 2014: February 25-26, 2014

    SciTech Connect

    Kurtz, S.

    2014-02-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  19. Photovoltaic Module Reliability Workshop 2012: February 28 - March 1, 2012

    SciTech Connect

    Kurtz, S.

    2013-11-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  20. Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010

    SciTech Connect

    Kurtz, J.

    2013-11-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  1. Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013

    SciTech Connect

    Kurtz, S.

    2013-10-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  2. Photovoltaic Module Reliability Workshop 2011: February 16-17, 2011

    SciTech Connect

    Kurtz, S.

    2013-11-01

    NREL's Photovoltaic (PV) Module Reliability Workshop (PVMRW) brings together PV reliability experts to share information, leading to the improvement of PV module reliability. Such improvement reduces the cost of solar electricity and promotes investor confidence in the technology--both critical goals for moving PV technologies deeper into the electricity marketplace.

  3. Proposed reliability cost model

    NASA Technical Reports Server (NTRS)

    Delionback, L. M.

    1973-01-01

    The research investigations which were involved in the study include: cost analysis/allocation, reliability and product assurance, forecasting methodology, systems analysis, and model-building. This is a classic example of an interdisciplinary problem, since the model-building requirements include the need for understanding and communication between technical disciplines on one hand, and the financial/accounting skill categories on the other. The systems approach is utilized within this context to establish a clearer and more objective relationship between reliability assurance and the subcategories (or subelements) that provide, or reenforce, the reliability assurance for a system. Subcategories are further subdivided as illustrated by a tree diagram. The reliability assurance elements can be seen to be potential alternative strategies, or approaches, depending on the specific goals/objectives of the trade studies. The scope was limited to the establishment of a proposed reliability cost-model format. The model format/approach is dependent upon the use of a series of subsystem-oriented CER's and sometimes possible CTR's, in devising a suitable cost-effective policy.

  4. Orbiter Autoland reliability analysis

    NASA Technical Reports Server (NTRS)

    Welch, D. Phillip

    1993-01-01

    The Space Shuttle Orbiter is the only space reentry vehicle in which the crew is seated upright. This position presents some physiological effects requiring countermeasures to prevent a crewmember from becoming incapacitated. This also introduces a potential need for automated vehicle landing capability. Autoland is a primary procedure that was identified as a requirement for landing following and extended duration orbiter mission. This report documents the results of the reliability analysis performed on the hardware required for an automated landing. A reliability block diagram was used to evaluate system reliability. The analysis considers the manual and automated landing modes currently available on the Orbiter. (Autoland is presently a backup system only.) Results of this study indicate a +/- 36 percent probability of successfully extending a nominal mission to 30 days. Enough variations were evaluated to verify that the reliability could be altered with missions planning and procedures. If the crew is modeled as being fully capable after 30 days, the probability of a successful manual landing is comparable to that of Autoland because much of the hardware is used for both manual and automated landing modes. The analysis indicates that the reliability for the manual mode is limited by the hardware and depends greatly on crew capability. Crew capability for a successful landing after 30 days has not been determined yet.

  5. Reliable and robust entanglement witness

    NASA Astrophysics Data System (ADS)

    Yuan, Xiao; Mei, Quanxin; Zhou, Shan; Ma, Xiongfeng

    2016-04-01

    Entanglement, a critical resource for quantum information processing, needs to be witnessed in many practical scenarios. Theoretically, witnessing entanglement is by measuring a special Hermitian observable, called an entanglement witness (EW), which has non-negative expected outcomes for all separable states but can have negative expectations for certain entangled states. In practice, an EW implementation may suffer from two problems. The first one is reliability. Due to unreliable realization devices, a separable state could be falsely identified as an entangled one. The second problem relates to robustness. A witness may not be optimal for a target state and fail to identify its entanglement. To overcome the reliability problem, we employ a recently proposed measurement-device-independent entanglement witness scheme, in which the correctness of the conclusion is independent of the implemented measurement devices. In order to overcome the robustness problem, we optimize the EW to draw a better conclusion given certain experimental data. With the proposed EW scheme, where only data postprocessing needs to be modified compared to the original measurement-device-independent scheme, one can efficiently take advantage of the measurement results to maximally draw reliable conclusions.

  6. Back to the Basics: In Defense of Achievement (and Achievement Tests) in College Admissions

    ERIC Educational Resources Information Center

    Geiser, Saul

    2009-01-01

    In this article, the author describes the growth and acceptance of achievement tests, such as the Scholastic Aptitude Test (SAT), over the past century, advocating that many SAT claims of equity, uniformity, technical reliability, and prediction, over traditional measures of academic achievement have been found to be illusory. Summarizing a series…

  7. Reliability Centered Maintenance - Methodologies

    NASA Technical Reports Server (NTRS)

    Kammerer, Catherine C.

    2009-01-01

    Journal article about Reliability Centered Maintenance (RCM) methodologies used by United Space Alliance, LLC (USA) in support of the Space Shuttle Program at Kennedy Space Center. The USA Reliability Centered Maintenance program differs from traditional RCM programs because various methodologies are utilized to take advantage of their respective strengths for each application. Based on operational experience, USA has customized the traditional RCM methodology into a streamlined lean logic path and has implemented the use of statistical tools to drive the process. USA RCM has integrated many of the L6S tools into both RCM methodologies. The tools utilized in the Measure, Analyze, and Improve phases of a Lean Six Sigma project lend themselves to application in the RCM process. All USA RCM methodologies meet the requirements defined in SAE JA 1011, Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes. The proposed article explores these methodologies.

  8. Software reliability perspectives

    NASA Technical Reports Server (NTRS)

    Wilson, Larry; Shen, Wenhui

    1987-01-01

    Software which is used in life critical functions must be known to be highly reliable before installation. This requires a strong testing program to estimate the reliability, since neither formal methods, software engineering nor fault tolerant methods can guarantee perfection. Prior to the final testing software goes through a debugging period and many models have been developed to try to estimate reliability from the debugging data. However, the existing models are poorly validated and often give poor performance. This paper emphasizes the fact that part of their failures can be attributed to the random nature of the debugging data given to these models as input, and it poses the problem of correcting this defect as an area of future research.

  9. Quality control and reliability of reported doses.

    PubMed

    Stadtmann, H; Figel, Markus; Kamenopoulou, V; Kluszczynski, D; Roed, H; Van Dijk, J

    2004-01-01

    Results of performance tests verifying the dosimetric properties of dosimetric systems are published in various reports (e.g. IAEA and EURADOS). However, there is hardly any information in the open literature relating to the uncertainty in a dose measurement or in the annual dose, which is increased by failure of the evaluation or data management system, damage of the dosemeter itself or by the loss of dosemeter. In this article, an attempt is made to estimate the importance of the above-mentioned conditions. This is achieved by sending questionnaires to about 200 approved dosimetric services in Europe. In total 88 questionnaires were returned and analysed. In the questionnaires, the frequency of occurrence of the various error conditions were investigated. Participants were also asked to evaluate the impact of the error condition from a dosimetric point of view and what countermeasures are taken. The article summarises all responses and compares different sources of errors according to their impact on the uncertainty of the resulting dose and gives a comprehensive overview on quality control actions and reliability on reported doses from European dosimetric services. PMID:15574990

  10. Materials reliability issues in microelectronics

    SciTech Connect

    Lloyd, J.R. ); Yost, F.G. ); Ho, P.S. )

    1991-01-01

    This book covers the proceedings of a MRS symposium on materials reliability in microelectronics. Topics include: electromigration; stress effects on reliability; stress and packaging; metallization; device, oxide and dielectric reliability; new investigative techniques; and corrosion.

  11. Reliability assessment for components of large scale photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Ahadi, Amir; Ghadimi, Noradin; Mirabbasi, Davar

    2014-10-01

    Photovoltaic (PV) systems have significantly shifted from independent power generation systems to a large-scale grid-connected generation systems in recent years. The power output of PV systems is affected by the reliability of various components in the system. This study proposes an analytical approach to evaluate the reliability of large-scale, grid-connected PV systems. The fault tree method with an exponential probability distribution function is used to analyze the components of large-scale PV systems. The system is considered in the various sequential and parallel fault combinations in order to find all realistic ways in which the top or undesired events can occur. Additionally, it can identify areas that the planned maintenance should focus on. By monitoring the critical components of a PV system, it is possible not only to improve the reliability of the system, but also to optimize the maintenance costs. The latter is achieved by informing the operators about the system component's status. This approach can be used to ensure secure operation of the system by its flexibility in monitoring system applications. The implementation demonstrates that the proposed method is effective and efficient and can conveniently incorporate more system maintenance plans and diagnostic strategies.

  12. Gearbox Reliability Collaborative Phase 3 Gearbox 2 Test Plan

    SciTech Connect

    Link, H.; Keller, J.; Guo, Y.; McNiff, B.

    2013-04-01

    Gearboxes in wind turbines have not been achieving their expected design life even though they commonly meet or exceed the design criteria specified in current design standards. One of the basic premises of the National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) is that the low gearbox reliability results from the absence of critical elements in the design process or insufficient design tools. Key goals of the GRC are to improve design approaches and analysis tools and to recommend practices and test methods resulting in improved design standards for wind turbine gearboxes that lower the cost of energy (COE) through improved reliability. The GRC uses a combined gearbox testing, modeling and analysis approach, along with a database of information from gearbox failures collected from overhauls and investigation of gearbox condition monitoring techniques to improve wind turbine operations and maintenance practices. Testing of Gearbox 2 (GB2) using the two-speed turbine controller that has been used in prior testing. This test series will investigate non-torque loads, high-speed shaft misalignment, and reproduction of field conditions in the dynamometer. This test series will also include vibration testing using an eddy-current brake on the gearbox's high speed shaft.

  13. Reliability and availability studies in the RIA driver linac.

    SciTech Connect

    Lessner, E. S.; Ostroumov, P. N.; Physics

    2005-01-01

    The Rare Isotope Accelerator (RIA) facility will include various complex systems and must provide radioactive beams to many users simultaneously. The availability of radioactive beams for most experiments at the fully-commissioned facility should be as high as possible within design cost limitations. To make a realistic estimate of the achievable reliability a detailed analysis is required. The RIA driver linac is a complex machine containing a large number of superconducting (SC) resonators and capable of accelerating multiple-charge-state beams [1]. At the pre-CDR stage of the design it is essential to identify critical facility subsystem failures that can prevent the driver linac from operating. The reliability and availability of the driver linac were studied using expert information and data from operating machines such as ATLAS, APS, JLab, and LANL. Availability studies are performed with a Monte-Carlo simulation code previously applied to availability assessments of the NLC facility [2] and the results used to identify subsystem failures that most affect the availability and reliability of the RIA driver, and guide design iterations and component specifications to address identified problems.

  14. Reliability and Failure in NASA Missions: Blunders, Normal Accidents, High Reliability, Bad Luck

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.

    2015-01-01

    NASA emphasizes crew safety and system reliability but several unfortunate failures have occurred. The Apollo 1 fire was mistakenly unanticipated. After that tragedy, the Apollo program gave much more attention to safety. The Challenger accident revealed that NASA had neglected safety and that management underestimated the high risk of shuttle. Probabilistic Risk Assessment was adopted to provide more accurate failure probabilities for shuttle and other missions. NASA's "faster, better, cheaper" initiative and government procurement reform led to deliberately dismantling traditional reliability engineering. The Columbia tragedy and Mars mission failures followed. Failures can be attributed to blunders, normal accidents, or bad luck. Achieving high reliability is difficult but possible.

  15. Reliability for Identification of a Select Set of Temporal and Physiologic Features of Infant Swallows.

    PubMed

    Gosa, Memorie M; Suiter, Debra M; Kahane, Joel C

    2015-06-01

    There is little reported evidence regarding the reliability of temporal and physiologic features of infant swallowing from videofluoroscopic swallowing studies (VFSS). The purpose of this retrospective study was to determine a reliable set of temporal and physiologic features from infant swallowing that can be measured from analysis of VFSS. Temporal and physiologic features for testing were determined from review of previously reported features of infant VFSS in the literature. Two novel analysts underwent three training sessions to learn and practice visual recognition of the proposed features. The two analysts then assessed 25 swallows from 10 total subjects' VFSS. To establish inter- and intra-rater reliability, calculation of Pearson's r was used for features that met criteria for parametric analysis and Spearman's rank correlation coefficient was used for the non-continuous features. Percent agreement was used to report on the reliability of the dichotomous features due to insufficient variability for Spearman's rho analyses. Fifteen of the 16 tested features were found to have acceptable inter- and intra-rater reliability measures, with each analyst achieving a correlation of 0.75 or higher. This project identifies 15 variables that can be reliably measured from infant VFSS. This information can be used to assist with determination of normal versus abnormal swallow features and in developing and testing therapeutic strategies for infants with dysphagia. PMID:25840787

  16. Designing reliability into accelerators

    SciTech Connect

    Hutton, A.

    1992-08-01

    For the next generation of high performance, high average luminosity colliders, the ``factories,`` reliability engineering must be introduced right at the inception of the project and maintained as a central theme throughout the project. There are several aspects which will be addressed separately: Concept; design; motivation; management techniques; and fault diagnosis.

  17. Designing reliability into accelerators

    SciTech Connect

    Hutton, A.

    1992-08-01

    For the next generation of high performance, high average luminosity colliders, the factories,'' reliability engineering must be introduced right at the inception of the project and maintained as a central theme throughout the project. There are several aspects which will be addressed separately: Concept; design; motivation; management techniques; and fault diagnosis.

  18. Software reliability report

    NASA Technical Reports Server (NTRS)

    Wilson, Larry

    1991-01-01

    There are many software reliability models which try to predict future performance of software based on data generated by the debugging process. Unfortunately, the models appear to be unable to account for the random nature of the data. If the same code is debugged multiple times and one of the models is used to make predictions, intolerable variance is observed in the resulting reliability predictions. It is believed that data replication can remove this variance in lab type situations and that it is less than scientific to talk about validating a software reliability model without considering replication. It is also believed that data replication may prove to be cost effective in the real world, thus the research centered on verification of the need for replication and on methodologies for generating replicated data in a cost effective manner. The context of the debugging graph was pursued by simulation and experimentation. Simulation was done for the Basic model and the Log-Poisson model. Reasonable values of the parameters were assigned and used to generate simulated data which is then processed by the models in order to determine limitations on their accuracy. These experiments exploit the existing software and program specimens which are in AIR-LAB to measure the performance of reliability models.

  19. Software Reliability Measurement Experience

    NASA Technical Reports Server (NTRS)

    Nikora, A. P.

    1993-01-01

    In this chapter, we describe a recent study of software reliability measurement methods that was conducted at the Jet Propulsion Laboratory. The first section of the chapter, sections 8.1, summarizes the study, characterizes the participating projects, describes the available data, and summarizes the tudy's results.

  20. Reliable solar cookers

    SciTech Connect

    Magney, G.K.

    1992-12-31

    The author describes the activities of SERVE, a Christian relief and development agency, to introduce solar ovens to the Afghan refugees in Pakistan. It has provided 5,000 solar cookers since 1984. The experience has demonstrated the potential of the technology and the need for a durable and reliable product. Common complaints about the cookers are discussed and the ideal cooker is described.

  1. Parametric Mass Reliability Study

    NASA Technical Reports Server (NTRS)

    Holt, James P.

    2014-01-01

    The International Space Station (ISS) systems are designed based upon having redundant systems with replaceable orbital replacement units (ORUs). These ORUs are designed to be swapped out fairly quickly, but some are very large, and some are made up of many components. When an ORU fails, it is replaced on orbit with a spare; the failed unit is sometimes returned to Earth to be serviced and re-launched. Such a system is not feasible for a 500+ day long-duration mission beyond low Earth orbit. The components that make up these ORUs have mixed reliabilities. Components that make up the most mass-such as computer housings, pump casings, and the silicon board of PCBs-typically are the most reliable. Meanwhile components that tend to fail the earliest-such as seals or gaskets-typically have a small mass. To better understand the problem, my project is to create a parametric model that relates both the mass of ORUs to reliability, as well as the mass of ORU subcomponents to reliability.

  2. Nonparametric Methods in Reliability

    PubMed Central

    Hollander, Myles; Peña, Edsel A.

    2005-01-01

    Probabilistic and statistical models for the occurrence of a recurrent event over time are described. These models have applicability in the reliability, engineering, biomedical and other areas where a series of events occurs for an experimental unit as time progresses. Nonparametric inference methods, in particular, the estimation of a relevant distribution function, are described. PMID:16710444

  3. Reliability of fiber optic emitters

    NASA Astrophysics Data System (ADS)

    Twu, B.; Kung, H.

    1982-08-01

    Over the past few years a number of fiber optic links were introduced by an American company. Various transmitter-fiber-receiver combinations were studied to satisfy different link performance and reliability requirements. Light emitting diodes (LEDs) were generally used in the transmitter mode. Attention is given to the characteristics of four types of LED's which had been developed, GaAsP LEDs were made from epi-layers grown by vapor phase epitaxy on GaAs substrate. The composition of GaAs and GaP was adjusted to achieve light emission at the desired wavelength. The p-n junction was formed by diffusing zinc into n type epi-layers. GaAlAs LEDs were made from epi-layers grown by liquid phase epitaxy on GaAs substrate. Long term reliability of four LEDs was evaluated. GaAsP diodes showed gradual degradation as a whole. GaAlAs emitters showed insignificant gradual degradation, but they exhibited dark line or dark spot related catastrophic degradation.

  4. Achieving Safety through Security Management

    NASA Astrophysics Data System (ADS)

    Ridgway, John

    Whilst the achievement of safety objectives may not be possible purely through the administration of an effective Information Security Management System (ISMS), your job as safety manager will be significantly eased if such a system is in place. This paper seeks to illustrate the point by drawing a comparison between two of the prominent standards within the two disciplines of security and safety management.

  5. Multi-Disciplinary System Reliability Analysis

    NASA Technical Reports Server (NTRS)

    Mahadevan, Sankaran; Han, Song

    1997-01-01

    The objective of this study is to develop a new methodology for estimating the reliability of engineering systems that encompass multiple disciplines. The methodology is formulated in the context of the NESSUS probabilistic structural analysis code developed under the leadership of NASA Lewis Research Center. The NESSUS code has been successfully applied to the reliability estimation of a variety of structural engineering systems. This study examines whether the features of NESSUS could be used to investigate the reliability of systems in other disciplines such as heat transfer, fluid mechanics, electrical circuits etc., without considerable programming effort specific to each discipline. In this study, the mechanical equivalence between system behavior models in different disciplines are investigated to achieve this objective. A new methodology is presented for the analysis of heat transfer, fluid flow, and electrical circuit problems using the structural analysis routines within NESSUS, by utilizing the equivalence between the computational quantities in different disciplines. This technique is integrated with the fast probability integration and system reliability techniques within the NESSUS code, to successfully compute the system reliability of multi-disciplinary systems. Traditional as well as progressive failure analysis methods for system reliability estimation are demonstrated, through a numerical example of a heat exchanger system involving failure modes in structural, heat transfer and fluid flow disciplines.

  6. Reliability in perceptual analysis of voice quality.

    PubMed

    Bele, Irene Velsvik

    2005-12-01

    This study focuses on speaking voice quality in male teachers (n = 35) and male actors (n = 36), who represent untrained and trained voice users, because we wanted to investigate normal and supranormal voices. In this study, both substantial and methodologic aspects were considered. It includes a method for perceptual voice evaluation, and a basic issue was rater reliability. A listening group of 10 listeners, 7 experienced speech-language therapists, and 3 speech-language therapist students evaluated the voices by 15 vocal characteristics using VA scales. Two sets of voice signals were investigated: text reading (2 loudness levels) and sustained vowel (3 levels). The results indicated a high interrater reliability for most perceptual characteristics. Connected speech was evaluated more reliably, especially at the normal level, but both types of voice signals were evaluated reliably, although the reliability for connected speech was somewhat higher than for vowels. Experienced listeners tended to be more consistent in their ratings than did the student raters. Some vocal characteristics achieved acceptable reliability even with a smaller panel of listeners. The perceptual characteristics grouped in 4 factors reflected perceptual dimensions. PMID:16301102

  7. Teacher Involvement To Evaluate Science Achievement.

    ERIC Educational Resources Information Center

    Ediger, Marlow

    Teacher-developed tests can be more valid and reliable than standardized tests or state-mandated tests in evaluating student achievement in science. Many teachers, however, are not acquainted with the standards to use in test writing. The National Research Council has released "Classroom Assessment and the National Education Standards," a…

  8. Measurement Practices for Reliability and Power Quality

    SciTech Connect

    Kueck, JD

    2005-05-06

    to support activities to develop and share information among industry and regulatory participants about critical resources and practices. The toolkit has been developed by investigating the status of indices and definitions, surveying utility organizations on information sharing, and preparing summaries of reliability standards and monitoring requirements--the issues, needs, work under way, existing standards, practices and guidelines--for the following three classifications: (1) terms and definitions of reliability; (2) power quality standards, guidelines, and measurements; and (3) activities and organizations developing and sharing information on distribution reliability. As these synopses of reliability measurement practices are provided, it must be noted that an economic penalty may be associated with requiring too high a reliability level from the distribution system for all customers. It may be appropriate for the distribution system to supply only some base, generally accepted level of reliability. This base level would be adequate for the majority of customers. Users who need a higher level may find it economical to supply using distributed energy resources (DER) and other local solutions to reliability and power quality needs. Local solutions implemented by the customer may be the most cost-effective method for addressing the more stringent needs of a digital economy. These local solutions include energy storage, small distributed generators, and microgrids. This report also considers the market's role in addressing reliability issues and requirements. The customer's needs are discussed in view of issues such as power quality requirements of digital electronic equipment, the cost of outages, the cost of storage and new infrastructure, and natural gas prices. The market role in addressing these issues and requirements is explored. The economic considerations associated with the reliability issues are discussed, as well as the levels at which these economic

  9. Space Shuttle Propulsion System Reliability

    NASA Technical Reports Server (NTRS)

    Welzyn, Ken; VanHooser, Katherine; Moore, Dennis; Wood, David

    2011-01-01

    This session includes the following sessions: (1) External Tank (ET) System Reliability and Lessons, (2) Space Shuttle Main Engine (SSME), Reliability Validated by a Million Seconds of Testing, (3) Reusable Solid Rocket Motor (RSRM) Reliability via Process Control, and (4) Solid Rocket Booster (SRB) Reliability via Acceptance and Testing.

  10. Reliable broadcast protocols

    NASA Technical Reports Server (NTRS)

    Joseph, T. A.; Birman, Kenneth P.

    1989-01-01

    A number of broadcast protocols that are reliable subject to a variety of ordering and delivery guarantees are considered. Developing applications that are distributed over a number of sites and/or must tolerate the failures of some of them becomes a considerably simpler task when such protocols are available for communication. Without such protocols the kinds of distributed applications that can reasonably be built will have a very limited scope. As the trend towards distribution and decentralization continues, it will not be surprising if reliable broadcast protocols have the same role in distributed operating systems of the future that message passing mechanisms have in the operating systems of today. On the other hand, the problems of engineering such a system remain large. For example, deciding which protocol is the most appropriate to use in a certain situation or how to balance the latency-communication-storage costs is not an easy question.

  11. Data networks reliability

    NASA Astrophysics Data System (ADS)

    Gallager, Robert G.

    1988-10-01

    The research from 1984 to 1986 on Data Network Reliability had the objective of developing general principles governing the reliable and efficient control of data networks. The research was centered around three major areas: congestion control, multiaccess networks, and distributed asynchronous algorithms. The major topics within congestion control were the use of flow control algorithms. The major topics within congestion control were the use of flow control to reduce congestion and the use of routing to reduce congestion. The major topics within multiaccess networks were the communication properties of multiaccess channels, collision resolution, and packet radio networks. The major topics within asynchronous distributed algorithms were failure recovery, time vs. communication tradeoffs, and the general theory of distributed algorithms.

  12. Human Reliability Program Workshop

    SciTech Connect

    Landers, John; Rogers, Erin; Gerke, Gretchen

    2014-05-18

    A Human Reliability Program (HRP) is designed to protect national security as well as worker and public safety by continuously evaluating the reliability of those who have access to sensitive materials, facilities, and programs. Some elements of a site HRP include systematic (1) supervisory reviews, (2) medical and psychological assessments, (3) management evaluations, (4) personnel security reviews, and (4) training of HRP staff and critical positions. Over the years of implementing an HRP, the Department of Energy (DOE) has faced various challenges and overcome obstacles. During this 4-day activity, participants will examine programs that mitigate threats to nuclear security and the insider threat to include HRP, Nuclear Security Culture (NSC) Enhancement, and Employee Assistance Programs. The focus will be to develop an understanding of the need for a systematic HRP and to discuss challenges and best practices associated with mitigating the insider threat.

  13. Reliability of photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Ross, R. G., Jr.

    1986-01-01

    In order to assess the reliability of photovoltaic modules, four categories of known array failure and degradation mechanisms are discussed, and target reliability allocations have been developed within each category based on the available technology and the life-cycle-cost requirements of future large-scale terrestrial applications. Cell-level failure mechanisms associated with open-circuiting or short-circuiting of individual solar cells generally arise from cell cracking or the fatigue of cell-to-cell interconnects. Power degradation mechanisms considered include gradual power loss in cells, light-induced effects, and module optical degradation. Module-level failure mechanisms and life-limiting wear-out mechanisms are also explored.

  14. Construction of Valid and Reliable Test for Assessment of Students

    ERIC Educational Resources Information Center

    Osadebe, P. U.

    2015-01-01

    The study was carried out to construct a valid and reliable test in Economics for secondary school students. Two research questions were drawn to guide the establishment of validity and reliability for the Economics Achievement Test (EAT). It is a multiple choice objective test of five options with 100 items. A sample of 1000 students was randomly…

  15. Methodology for Physics and Engineering of Reliable Products

    NASA Technical Reports Server (NTRS)

    Cornford, Steven L.; Gibbel, Mark

    1996-01-01

    Physics of failure approaches have gained wide spread acceptance within the electronic reliability community. These methodologies involve identifying root cause failure mechanisms, developing associated models, and utilizing these models to inprove time to market, lower development and build costs and higher reliability. The methodology outlined herein sets forth a process, based on integration of both physics and engineering principles, for achieving the same goals.

  16. Development and Reliability Evaluation of the Movement Rating Instrument for Virtual Reality Video Game Play

    PubMed Central

    Nawrotek, Joanna; Deschenes, Emilie; Giguere, Tia; Serafin, Julie; Bilodeau, Martin; Sveistrup, Heidi

    2016-01-01

    Background Virtual reality active video games are increasingly popular physical therapy interventions for children with cerebral palsy. However, physical therapists require educational resources to support decision making about game selection to match individual patient goals. Quantifying the movements elicited during virtual reality active video game play can inform individualized game selection in pediatric rehabilitation. Objective The objectives of this study were to develop and evaluate the feasibility and reliability of the Movement Rating Instrument for Virtual Reality Game Play (MRI-VRGP). Methods Item generation occurred through an iterative process of literature review and sample videotape viewing. The MRI-VRGP includes 25 items quantifying upper extremity, lower extremity, and total body movements. A total of 176 videotaped 90-second game play sessions involving 7 typically developing children and 4 children with cerebral palsy were rated by 3 raters trained in MRI-VRGP use. Children played 8 games on 2 virtual reality and active video game systems. Intraclass correlation coefficients (ICCs) determined intra-rater and interrater reliability. Results Excellent intrarater reliability was evidenced by ICCs of >0.75 for 17 of the 25 items across the 3 raters. Interrater reliability estimates were less precise. Excellent interrater reliability was achieved for far reach upper extremity movements (ICC=0.92 [for right and ICC=0.90 for left) and for squat (ICC=0.80) and jump items (ICC=0.99), with 9 items achieving ICCs of >0.70, 12 items achieving ICCs of between 0.40 and 0.70, and 4 items achieving poor reliability (close-reach upper extremity-ICC=0.14 for right and ICC=0.07 for left) and single-leg stance (ICC=0.55 for right and ICC=0.27 for left). Conclusions Poor video quality, differing item interpretations between raters, and difficulty quantifying the high-speed movements involved in game play affected reliability. With item definition clarification and

  17. Compact, Reliable EEPROM Controller

    NASA Technical Reports Server (NTRS)

    Katz, Richard; Kleyner, Igor

    2010-01-01

    A compact, reliable controller for an electrically erasable, programmable read-only memory (EEPROM) has been developed specifically for a space-flight application. The design may be adaptable to other applications in which there are requirements for reliability in general and, in particular, for prevention of inadvertent writing of data in EEPROM cells. Inadvertent writes pose risks of loss of reliability in the original space-flight application and could pose such risks in other applications. Prior EEPROM controllers are large and complex and do not provide all reasonable protections (in many cases, few or no protections) against inadvertent writes. In contrast, the present controller provides several layers of protection against inadvertent writes. The controller also incorporates a write-time monitor, enabling determination of trends in the performance of an EEPROM through all phases of testing. The controller has been designed as an integral subsystem of a system that includes not only the controller and the controlled EEPROM aboard a spacecraft but also computers in a ground control station, relatively simple onboard support circuitry, and an onboard communication subsystem that utilizes the MIL-STD-1553B protocol. (MIL-STD-1553B is a military standard that encompasses a method of communication and electrical-interface requirements for digital electronic subsystems connected to a data bus. MIL-STD- 1553B is commonly used in defense and space applications.) The intent was to both maximize reliability while minimizing the size and complexity of onboard circuitry. In operation, control of the EEPROM is effected via the ground computers, the MIL-STD-1553B communication subsystem, and the onboard support circuitry, all of which, in combination, provide the multiple layers of protection against inadvertent writes. There is no controller software, unlike in many prior EEPROM controllers; software can be a major contributor to unreliability, particularly in fault

  18. Spacecraft transmitter reliability

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A workshop on spacecraft transmitter reliability was held at the NASA Lewis Research Center on September 25 and 26, 1979, to discuss present knowledge and to plan future research areas. Since formal papers were not submitted, this synopsis was derived from audio tapes of the workshop. The following subjects were covered: users' experience with space transmitters; cathodes; power supplies and interfaces; and specifications and quality assurance. A panel discussion ended the workshop.

  19. Reliability and testing

    NASA Technical Reports Server (NTRS)

    Auer, Werner

    1996-01-01

    Reliability and its interdependence with testing are important topics for development and manufacturing of successful products. This generally accepted fact is not only a technical statement, but must be also seen in the light of 'Human Factors.' While the background for this paper is the experience gained with electromechanical/electronic space products, including control and system considerations, it is believed that the content could be also of interest for other fields.

  20. Software reliability studies

    NASA Technical Reports Server (NTRS)

    Hoppa, Mary Ann; Wilson, Larry W.

    1994-01-01

    There are many software reliability models which try to predict future performance of software based on data generated by the debugging process. Our research has shown that by improving the quality of the data one can greatly improve the predictions. We are working on methodologies which control some of the randomness inherent in the standard data generation processes in order to improve the accuracy of predictions. Our contribution is twofold in that we describe an experimental methodology using a data structure called the debugging graph and apply this methodology to assess the robustness of existing models. The debugging graph is used to analyze the effects of various fault recovery orders on the predictive accuracy of several well-known software reliability algorithms. We found that, along a particular debugging path in the graph, the predictive performance of different models can vary greatly. Similarly, just because a model 'fits' a given path's data well does not guarantee that the model would perform well on a different path. Further we observed bug interactions and noted their potential effects on the predictive process. We saw that not only do different faults fail at different rates, but that those rates can be affected by the particular debugging stage at which the rates are evaluated. Based on our experiment, we conjecture that the accuracy of a reliability prediction is affected by the fault recovery order as well as by fault interaction.

  1. Comparing Science Achievement Constructs: Targeted and Achieved

    ERIC Educational Resources Information Center

    Ferrara, Steve; Duncan, Teresa

    2011-01-01

    This article illustrates how test specifications based solely on academic content standards, without attention to other cognitive skills and item response demands, can fall short of their targeted constructs. First, the authors inductively describe the science achievement construct represented by a statewide sixth-grade science proficiency test.…

  2. General Aviation Aircraft Reliability Study

    NASA Technical Reports Server (NTRS)

    Pettit, Duane; Turnbull, Andrew; Roelant, Henk A. (Technical Monitor)

    2001-01-01

    This reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was prudent. This was accomplished by benchmarking the reliability of operational Complex GA Aircraft Systems. Specifically, Complex GA Aircraft System reliability was estimated using data obtained from the logbooks of a random sample of the Complex GA Aircraft population.

  3. Varieties of Achievement Motivation.

    ERIC Educational Resources Information Center

    Kukla, Andre; Scher, Hal

    1986-01-01

    A recent article by Nicholls on achievement motivation is criticized on three points: (1) definitions of achievement motives are ambiguous; (2) behavioral consequences predicted do not follow from explicit theoretical assumptions; and (3) Nicholls's account of the relation between his theory and other achievement theories is factually incorrect.…

  4. Motivation and School Achievement.

    ERIC Educational Resources Information Center

    Maehr, Martin L.; Archer, Jennifer

    Addressing the question, "What can be done to promote school achievement?", this paper summarizes the literature on motivation relating to classroom achievement and school effectiveness. Particular attention is given to how values, ideology, and various cultural patterns impinge on classroom performance and serve to enhance motivation to achieve.…

  5. Mobility and Reading Achievement.

    ERIC Educational Resources Information Center

    Waters, Theresa Z.

    A study examined the effect of geographic mobility on elementary school students' achievement. Although such mobility, which requires students to make multiple moves among schools, can have a negative impact on academic achievement, the hypothesis for the study was that it was not a determining factor in reading achievement test scores. Subjects…

  6. PASS and Reading Achievement.

    ERIC Educational Resources Information Center

    Kirby, John R.

    Two studies examined the effectiveness of the PASS (Planning, Attention, Simultaneous, and Successive cognitive processes) theory of intelligence in predicting reading achievement scores of normally achieving children and distinguishing children with reading disabilities from normally achieving children. The first study dealt with predicting…

  7. Illustrated structural application of universal first-order reliability method

    NASA Technical Reports Server (NTRS)

    Verderaime, V.

    1994-01-01

    The general application of the proposed first-order reliability method was achieved through the universal normalization of engineering probability distribution data. The method superimposes prevailing deterministic techniques and practices on the first-order reliability method to surmount deficiencies of the deterministic method and provide benefits of reliability techniques and predictions. A reliability design factor is derived from the reliability criterion to satisfy a specified reliability and is analogous to the deterministic safety factor. Its application is numerically illustrated on several practical structural design and verification cases with interesting results and insights. Two concepts of reliability selection criteria are suggested. Though the method was developed to support affordable structures for access to space, the method should also be applicable for most high-performance air and surface transportation systems.

  8. A Reliability-Based Track Fusion Algorithm

    PubMed Central

    Xu, Li; Pan, Liqiang; Jin, Shuilin; Liu, Haibo; Yin, Guisheng

    2015-01-01

    The common track fusion algorithms in multi-sensor systems have some defects, such as serious imbalances between accuracy and computational cost, the same treatment of all the sensor information regardless of their quality, high fusion errors at inflection points. To address these defects, a track fusion algorithm based on the reliability (TFR) is presented in multi-sensor and multi-target environments. To improve the information quality, outliers in the local tracks are eliminated at first. Then the reliability of local tracks is calculated, and the local tracks with high reliability are chosen for the state estimation fusion. In contrast to the existing methods, TFR reduces high fusion errors at the inflection points of system tracks, and obtains a high accuracy with less computational cost. Simulation results verify the effectiveness and the superiority of the algorithm in dense sensor environments. PMID:25950174

  9. Photovoltaic-Reliability R&D Toward a Solar-Powered World (Presentation)

    SciTech Connect

    Kurtz, S.; Granata, J.

    2009-08-01

    Presentation about the importance of continued progress toward low-cost, high-reliability, and high-performance PV systems. High reliability is an essential element in achieving low-cost solar electricity.

  10. Reliability systems for implantable cardiac defibrillator batteries

    NASA Astrophysics Data System (ADS)

    Takeuchi, Esther S.

    The reliability of the power sources used in implantable cardiac defibrillators is critical due to the life-saving nature of the device. Achieving a high reliability power source depends on several systems functioning together. Appropriate cell design is the first step in assuring a reliable product. Qualification of critical components and of the cells using those components is done prior to their designation as implantable grade. Product consistency is assured by control of manufacturing practices and verified by sampling plans using both accelerated and real-time testing. Results to date show that lithium/silver vanadium oxide cells used for implantable cardiac defibrillators have a calculated maximum random failure rate of 0.005% per test month.

  11. Reliability test procedures for tunable lasers

    NASA Astrophysics Data System (ADS)

    Ciminelli, Caterina; Armenise, Mario Nicola; Passaro, Vittorio M. N.

    2003-04-01

    Widely tunable lasers are promising sources for future high-capacity dense wavelength divison multiplexing and photonic switching systems. These devices can be used for sparing in the cold standby mode, restoring in hot standby restoring, rerouting wavelength rerouting or conversion, or fast switching in all-optical networks. Tunable lasers need to demonstrate some featuers such as wide tunability range, optical output power of 10 dBm or more, cost and structure similar to those of commercial DFB lasers. High performance devices would require low laser chirp, high modulation speed, small size and very high reliability. For system applications, requirements on the tunable laser reliability are very stringent. Reliability studies and appropriate related testing procedures are necessary to define stability of tunable lasers and their expected lifetime. In this paper we propose some reliabilty test 'strategies' useful for qualification of tunable lasers with reference to some critical issues of the main technologies used to achieve the tunability feature.

  12. Health Information on the Web: Finding Reliable Information

    MedlinePlus

    ... they're usually not supported by for-profit companies, such as drug or insurance companies. However, you still need to find out where ... with .com Web addresses may represent a specific company or be published by a company that uses ...

  13. Ultra Reliable Closed Loop Life Support for Long Space Missions

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.; Ewert, Michael K.

    2010-01-01

    Spacecraft human life support systems can achieve ultra reliability by providing sufficient spares to replace all failed components. The additional mass of spares for ultra reliability is approximately equal to the original system mass, provided that the original system reliability is not too low. Acceptable reliability can be achieved for the Space Shuttle and Space Station by preventive maintenance and by replacing failed units. However, on-demand maintenance and repair requires a logistics supply chain in place to provide the needed spares. In contrast, a Mars or other long space mission must take along all the needed spares, since resupply is not possible. Long missions must achieve ultra reliability, a very low failure rate per hour, since they will take years rather than weeks and cannot be cut short if a failure occurs. Also, distant missions have a much higher mass launch cost per kilogram than near-Earth missions. Achieving ultra reliable spacecraft life support systems with acceptable mass will require a well-planned and extensive development effort. Analysis must determine the reliability requirement and allocate it to subsystems and components. Ultra reliability requires reducing the intrinsic failure causes, providing spares to replace failed components and having "graceful" failure modes. Technologies, components, and materials must be selected and designed for high reliability. Long duration testing is needed to confirm very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The system must be designed, developed, integrated, and tested with system reliability in mind. Maintenance and reparability of failed units must not add to the probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass should start soon since it must be a long term effort.

  14. Reliable Signal Transduction

    NASA Astrophysics Data System (ADS)

    Wollman, Roy

    Stochasticity inherent to biochemical reactions (intrinsic noise) and variability in cellular states (extrinsic noise) degrade information transmitted through signaling networks. We analyzed the ability of temporal signal modulation - that is dynamics - to reduce noise-induced information loss. In the extracellular signal-regulated kinase (ERK), calcium (Ca(2 +)) , and nuclear factor kappa-B (NF- κB) pathways, response dynamics resulted in significantly greater information transmission capacities compared to nondynamic responses. Theoretical analysis demonstrated that signaling dynamics has a key role in overcoming extrinsic noise. Experimental measurements of information transmission in the ERK network under varying signal-to-noise levels confirmed our predictions and showed that signaling dynamics mitigate, and can potentially eliminate, extrinsic noise-induced information loss. By curbing the information-degrading effects of cell-to-cell variability, dynamic responses substantially increase the accuracy of biochemical signaling networks.

  15. Ultimately Reliable Pyrotechnic Systems

    NASA Technical Reports Server (NTRS)

    Scott, John H.; Hinkel, Todd

    2015-01-01

    This paper presents the methods by which NASA has designed, built, tested, and certified pyrotechnic devices for high reliability operation in extreme environments and illustrates the potential applications in the oil and gas industry. NASA's extremely successful application of pyrotechnics is built upon documented procedures and test methods that have been maintained and developed since the Apollo Program. Standards are managed and rigorously enforced for performance margins, redundancy, lot sampling, and personnel safety. The pyrotechnics utilized in spacecraft include such devices as small initiators and detonators with the power of a shotgun shell, detonating cord systems for explosive energy transfer across many feet, precision linear shaped charges for breaking structural membranes, and booster charges to actuate valves and pistons. NASA's pyrotechnics program is one of the more successful in the history of Human Spaceflight. No pyrotechnic device developed in accordance with NASA's Human Spaceflight standards has ever failed in flight use. NASA's pyrotechnic initiators work reliably in temperatures as low as -420 F. Each of the 135 Space Shuttle flights fired 102 of these initiators, some setting off multiple pyrotechnic devices, with never a failure. The recent landing on Mars of the Opportunity rover fired 174 of NASA's pyrotechnic initiators to complete the famous '7 minutes of terror.' Even after traveling through extreme radiation and thermal environments on the way to Mars, every one of them worked. These initiators have fired on the surface of Titan. NASA's design controls, procedures, and processes produce the most reliable pyrotechnics in the world. Application of pyrotechnics designed and procured in this manner could enable the energy industry's emergency equipment, such as shutoff valves and deep-sea blowout preventers, to be left in place for years in extreme environments and still be relied upon to function when needed, thus greatly enhancing

  16. CR reliability testing

    NASA Astrophysics Data System (ADS)

    Honeyman-Buck, Janice C.; Rill, Lynn; Frost, Meryll M.; Staab, Edward V.

    1998-07-01

    The purpose of this work was to develop a method for systematically testing the reliability of a CR system under realistic daily loads in a non-clinical environment prior to its clinical adoption. Once digital imaging replaces film, it will be very difficult to revert back should the digital system become unreliable. Prior to the beginning of the test, a formal evaluation was performed to set the benchmarks for performance and functionality. A formal protocol was established that included all the 62 imaging plates in the inventory for each 24-hour period in the study. Imaging plates were exposed using different combinations of collimation, orientation, and SID. Anthropomorphic phantoms were used to acquire images of different sizes. Each combination was chosen randomly to simulate the differences that could occur in clinical practice. The tests were performed over a wide range of times with batches of plates processed to simulate the temporal constraints required by the nature of portable radiographs taken in the Intensive Care Unit (ICU). Current patient demographics were used for the test studies so automatic routing algorithms could be tested. During the test, only three minor reliability problems occurred, two of which were not directly related to the CR unit. One plate was discovered to cause a segmentation error that essentially reduced the image to only black and white with no gray levels. This plate was removed from the inventory to be replaced. Another problem was a PACS routing problem that occurred when the DICOM server with which the CR was communicating had a problem with disk space. The final problem was a network printing failure to the laser cameras. Although the units passed the reliability test, problems with interfacing to workstations were discovered. The two issues that were identified were the interpretation of what constitutes a study for CR and the construction of the look-up table for a proper gray scale display.

  17. DMD reliability: a MEMS success story

    NASA Astrophysics Data System (ADS)

    Douglass, Michael

    2003-01-01

    The Digital Micromirror Device (DMD) developed by Texas Instruments (TI) has made tremendous progress in both performance and reliability since it was first invented in 1987. From the first working concept of a bistable mirror, the DMD is now providing high-brightness, high-contrast, and high-reliability in over 1,500,000 projectors using Digital Light Processing technology. In early 2000, TI introduced the first DMD chip with a smaller mirror (14-micron pitch versus 17-micron pitch). This allowed a greater number of high-resolution DMD chips per wafer, thus providing an increased output capacity as well as the flexibility to use existing package designs. By using existing package designs, subsequent DMDs cost less as well as met our customers' demand for faster time to market. In recent years, the DMD achieved the status of being a commercially successful MEMS device. It reached this status by the efforts of hundreds of individuals working toward a common goal over many years. Neither textbooks nor design guidelines existed at the time. There was little infrastructure in place to support such a large endeavor. The knowledge we gained through our characterization and testing was all we had available to us through the first few years of development. Reliability was only a goal in 1992 when production development activity started; a goal that many throughout the industry and even within Texas Instruments doubted the DMD could achieve. The results presented in this paper demonstrate that we succeeded by exceeding the reliability goals.

  18. Ferrite logic reliability study

    NASA Technical Reports Server (NTRS)

    Baer, J. A.; Clark, C. B.

    1973-01-01

    Development and use of digital circuits called all-magnetic logic are reported. In these circuits the magnetic elements and their windings comprise the active circuit devices in the logic portion of a system. The ferrite logic device belongs to the all-magnetic class of logic circuits. The FLO device is novel in that it makes use of a dual or bimaterial ferrite composition in one physical ceramic body. This bimaterial feature, coupled with its potential for relatively high speed operation, makes it attractive for high reliability applications. (Maximum speed of operation approximately 50 kHz.)

  19. Fault Tree Reliability Analysis and Design-for-reliability

    Energy Science and Technology Software Center (ESTSC)

    1998-05-05

    WinR provides a fault tree analysis capability for performing systems reliability and design-for-reliability analyses. The package includes capabilities for sensitivity and uncertainity analysis, field failure data analysis, and optimization.

  20. Complementary Reliability-Based Decodings of Binary Linear Block Codes

    NASA Technical Reports Server (NTRS)

    Fossorier, Marc P. C.; Lin, Shu

    1997-01-01

    This correspondence presents a hybrid reliability-based decoding algorithm which combines the reprocessing method based on the most reliable basis and a generalized Chase-type algebraic decoder based on the least reliable positions. It is shown that reprocessing with a simple additional algebraic decoding effort achieves significant coding gain. For long codes, the order of reprocessing required to achieve asymptotic optimum error performance is reduced by approximately 1/3. This significantly reduces the computational complexity, especially for long codes. Also, a more efficient criterion for stopping the decoding process is derived based on the knowledge of the algebraic decoding solution.

  1. On Component Reliability and System Reliability for Space Missions

    NASA Technical Reports Server (NTRS)

    Chen, Yuan; Gillespie, Amanda M.; Monaghan, Mark W.; Sampson, Michael J.; Hodson, Robert F.

    2012-01-01

    This paper is to address the basics, the limitations and the relationship between component reliability and system reliability through a study of flight computing architectures and related avionics components for NASA future missions. Component reliability analysis and system reliability analysis need to be evaluated at the same time, and the limitations of each analysis and the relationship between the two analyses need to be understood.

  2. Integrated circuit reliability testing

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G. (Inventor); Sayah, Hoshyar R. (Inventor)

    1990-01-01

    A technique is described for use in determining the reliability of microscopic conductors deposited on an uneven surface of an integrated circuit device. A wafer containing integrated circuit chips is formed with a test area having regions of different heights. At the time the conductors are formed on the chip areas of the wafer, an elongated serpentine assay conductor is deposited on the test area so the assay conductor extends over multiple steps between regions of different heights. Also, a first test conductor is deposited in the test area upon a uniform region of first height, and a second test conductor is deposited in the test area upon a uniform region of second height. The occurrence of high resistances at the steps between regions of different height is indicated by deriving the measured length of the serpentine conductor using the resistance measured between the ends of the serpentine conductor, and comparing that to the design length of the serpentine conductor. The percentage by which the measured length exceeds the design length, at which the integrated circuit will be discarded, depends on the required reliability of the integrated circuit.

  3. Integrated circuit reliability testing

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G. (Inventor); Sayah, Hoshyar R. (Inventor)

    1988-01-01

    A technique is described for use in determining the reliability of microscopic conductors deposited on an uneven surface of an integrated circuit device. A wafer containing integrated circuit chips is formed with a test area having regions of different heights. At the time the conductors are formed on the chip areas of the wafer, an elongated serpentine assay conductor is deposited on the test area so the assay conductor extends over multiple steps between regions of different heights. Also, a first test conductor is deposited in the test area upon a uniform region of first height, and a second test conductor is deposited in the test area upon a uniform region of second height. The occurrence of high resistances at the steps between regions of different height is indicated by deriving the measured length of the serpentine conductor using the resistance measured between the ends of the serpentine conductor, and comparing that to the design length of the serpentine conductor. The percentage by which the measured length exceeds the design length, at which the integrated circuit will be discarded, depends on the required reliability of the integrated circuit.

  4. Load Control System Reliability

    SciTech Connect

    Trudnowski, Daniel

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  5. Systems reliability analysis for the national ignition facility

    SciTech Connect

    Majumdar, K.C.; Annese, C.E.; MacIntyre, A.T.; Sicherman, A.

    1996-06-12

    A Reliability, Availability and Maintainability (RAM) analysis was initiated for the National Ignition Facility (NIF). The NIF is an inertial confinement fusion research facility designed to achieve controlled thermonuclear reaction; the preferred site for the NIF is the Lawrence Livermore National Laboratory (LLNL). The NIF RAM analysis has three purposes: (1) to allocate top level reliability and availability goals for the systems, (2) to develop an operability model for optimum maintainability, and (3) to determine the achievability of the allocated goals of the RAM parameters for the NIF systems and the facility operation as a whole. An allocation model assigns the reliability and availability goals for front line and support systems by a top-down approach; reliability analysis uses a bottom-up approach to determine the system reliability and availability from component level to system level.

  6. Schoolbook Texts: Behavioral Achievement Priming in Math and Language

    PubMed Central

    Engeser, Stefan; Baumann, Nicola; Baum, Ingrid

    2016-01-01

    Prior research found reliable and considerably strong effects of semantic achievement primes on subsequent performance. In order to simulate a more natural priming condition to better understand the practical relevance of semantic achievement priming effects, running texts of schoolbook excerpts with and without achievement primes were used as priming stimuli. Additionally, we manipulated the achievement context; some subjects received no feedback about their achievement and others received feedback according to a social or individual reference norm. As expected, we found a reliable (albeit small) positive behavioral priming effect of semantic achievement primes on achievement in math (Experiment 1) and language tasks (Experiment 2). Feedback moderated the behavioral priming effect less consistently than we expected. The implication that achievement primes in schoolbooks can foster performance is discussed along with general theoretical implications. PMID:26938446

  7. Formal methods and software reliability

    NASA Technical Reports Server (NTRS)

    Holzmann, Gerard J.

    2004-01-01

    In this position statement I briefly describe how the software reliability problem has changed over the years, and the primary reasons for the recent creation of the Laboratory for Reliable Software at JPL.

  8. An approach to solving large reliability models

    NASA Technical Reports Server (NTRS)

    Boyd, Mark A.; Veeraraghavan, Malathi; Dugan, Joanne Bechta; Trivedi, Kishor S.

    1988-01-01

    This paper describes a unified approach to the problem of solving large realistic reliability models. The methodology integrates behavioral decomposition, state trunction, and efficient sparse matrix-based numerical methods. The use of fault trees, together with ancillary information regarding dependencies to automatically generate the underlying Markov model state space is proposed. The effectiveness of this approach is illustrated by modeling a state-of-the-art flight control system and a multiprocessor system. Nonexponential distributions for times to failure of components are assumed in the latter example. The modeling tool used for most of this analysis is HARP (the Hybrid Automated Reliability Predictor).

  9. Reliability of the Granger causality inference

    NASA Astrophysics Data System (ADS)

    Zhou, Douglas; Zhang, Yaoyu; Xiao, Yanyang; Cai, David

    2014-04-01

    How to characterize information flows in physical, biological, and social systems remains a major theoretical challenge. Granger causality (GC) analysis has been widely used to investigate information flow through causal interactions. We address one of the central questions in GC analysis, that is, the reliability of the GC evaluation and its implications for the causal structures extracted by this analysis. Our work reveals that the manner in which a continuous dynamical process is projected or coarse-grained to a discrete process has a profound impact on the reliability of the GC inference, and different sampling may potentially yield completely opposite inferences. This inference hazard is present for both linear and nonlinear processes. We emphasize that there is a hazard of reaching incorrect conclusions about network topologies, even including statistical (such as small-world or scale-free) properties of the networks, when GC analysis is blindly applied to infer the network topology. We demonstrate this using a small-world network for which a drastic loss of small-world attributes occurs in the reconstructed network using the standard GC approach. We further show how to resolve the paradox that the GC analysis seemingly becomes less reliable when more information is incorporated using finer and finer sampling. Finally, we present strategies to overcome these inference artifacts in order to obtain a reliable GC result.

  10. Heritability of Creative Achievement

    ERIC Educational Resources Information Center

    Piffer, Davide; Hur, Yoon-Mi

    2014-01-01

    Although creative achievement is a subject of much attention to lay people, the origin of individual differences in creative accomplishments remain poorly understood. This study examined genetic and environmental influences on creative achievement in an adult sample of 338 twins (mean age = 26.3 years; SD = 6.6 years). Twins completed the Creative…

  11. Confronting the Achievement Gap

    ERIC Educational Resources Information Center

    Gardner, David

    2007-01-01

    This article talks about the large achievement gap between children of color and their white peers. The reasons for the achievement gap are varied. First, many urban minorities come from a background of poverty. One of the detrimental effects of growing up in poverty is receiving inadequate nourishment at a time when bodies and brains are rapidly…

  12. States Address Achievement Gaps.

    ERIC Educational Resources Information Center

    Christie, Kathy

    2002-01-01

    Summarizes 2 state initiatives to address the achievement gap: North Carolina's report by the Advisory Commission on Raising Achievement and Closing Gaps, containing an 11-point strategy, and Kentucky's legislation putting in place 10 specific processes. The North Carolina report is available at www.dpi.state.nc.us.closingthegap; Kentucky's…

  13. Wechsler Individual Achievement Test.

    ERIC Educational Resources Information Center

    Taylor, Ronald L.

    1999-01-01

    This article describes the Wechsler Individual Achievement Test, a comprehensive measure of achievement for individuals in grades K-12. Eight subtests assess mathematics reasoning, spelling, reading comprehension, numerical operations, listening comprehension, oral expression, and written expression. Its administration, standardization,…

  14. Inverting the Achievement Pyramid

    ERIC Educational Resources Information Center

    White-Hood, Marian; Shindel, Melissa

    2006-01-01

    Attempting to invert the pyramid to improve student achievement and increase all students' chances for success is not a new endeavor. For decades, educators have strategized, formed think tanks, and developed school improvement teams to find better ways to improve the achievement of all students. Currently, the No Child Left Behind Act (NCLB) is…

  15. Achievement Test Program.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Trade and Industrial Education Service.

    The Ohio Trade and Industrial Education Achievement Test battery is comprised of seven basic achievement tests: Machine Trades, Automotive Mechanics, Basic Electricity, Basic Electronics, Mechanical Drafting, Printing, and Sheet Metal. The tests were developed by subject matter committees and specialists in testing and research. The Ohio Trade and…

  16. Honoring Student Achievement

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    Is the concept of "honor roll" obsolete? The honor roll has always been a way for schools to recognize the academic achievement of their students. But does it motivate students? In this article, several elementary school principals share their views about honoring student achievement. Among others, Virginia principal Nancy Moga said that students…

  17. Achieving Perspective Transformation.

    ERIC Educational Resources Information Center

    Nowak, Jens

    Perspective transformation is a consciously achieved state in which the individual's perspective on life is transformed. The new perspective serves as a vantage point for life's actions and interactions, affecting the way life is lived. Three conditions are basic to achieving perspective transformation: (1) "feeling" experience, i.e., getting in…

  18. Achieving Public Schools

    ERIC Educational Resources Information Center

    Abowitz, Kathleen Knight

    2011-01-01

    Public schools are functionally provided through structural arrangements such as government funding, but public schools are achieved in substance, in part, through local governance. In this essay, Kathleen Knight Abowitz explains the bifocal nature of achieving public schools; that is, that schools are both subject to the unitary Public compact of…

  19. Achievement-Based Resourcing.

    ERIC Educational Resources Information Center

    Fletcher, Mike; And Others

    1992-01-01

    This collection of seven articles examines achievement-based resourcing (ABR), the concept that the funding of educational institutions should be linked to their success in promoting student achievement, with a focus on the application of ABR to postsecondary education in the United Kingdom. The articles include: (1) "Introduction" (Mick…

  20. Further discussion on reliability: the art of reliability estimation.

    PubMed

    Yang, Yanyun; Green, Samuel B

    2015-01-01

    Sijtsma and van der Ark (2015) focused in their lead article on three frameworks for reliability estimation in nursing research: classical test theory (CTT), factor analysis (FA), and generalizability theory. We extend their presentation with particular attention to CTT and FA methods. We first consider the potential of yielding an overly negative or an overly positive assessment of reliability based on coefficient alpha. Next, we discuss other CTT methods for estimating reliability and how the choice of methods affects the interpretation of the reliability coefficient. Finally, we describe FA methods, which not only permit an understanding of a measure's underlying structure but also yield a variety of reliability coefficients with different interpretations. On a more general note, we discourage reporting reliability as a two-choice outcome--unsatisfactory or satisfactory; rather, we recommend that nursing researchers make a conceptual and empirical argument about when a measure might be more or less reliable, depending on its use. PMID:25738627

  1. Making Reliability Arguments in Classrooms

    ERIC Educational Resources Information Center

    Parkes, Jay; Giron, Tilia

    2006-01-01

    Reliability methodology needs to evolve as validity has done into an argument supported by theory and empirical evidence. Nowhere is the inadequacy of current methods more visible than in classroom assessment. Reliability arguments would also permit additional methodologies for evidencing reliability in classrooms. It would liberalize methodology…

  2. Testing for PV Reliability (Presentation)

    SciTech Connect

    Kurtz, S.; Bansal, S.

    2014-09-01

    The DOE SUNSHOT workshop is seeking input from the community about PV reliability and how the DOE might address gaps in understanding. This presentation describes the types of testing that are needed for PV reliability and introduces a discussion to identify gaps in our understanding of PV reliability testing.

  3. Business of reliability

    NASA Astrophysics Data System (ADS)

    Engel, Pierre

    1999-12-01

    The presentation is organized around three themes: (1) The decrease of reception equipment costs allows non-Remote Sensing organization to access a technology until recently reserved to scientific elite. What this means is the rise of 'operational' executive agencies considering space-based technology and operations as a viable input to their daily tasks. This is possible thanks to totally dedicated ground receiving entities focusing on one application for themselves, rather than serving a vast community of users. (2) The multiplication of earth observation platforms will form the base for reliable technical and financial solutions. One obstacle to the growth of the earth observation industry is the variety of policies (commercial versus non-commercial) ruling the distribution of the data and value-added products. In particular, the high volume of data sales required for the return on investment does conflict with traditional low-volume data use for most applications. Constant access to data sources supposes monitoring needs as well as technical proficiency. (3) Large volume use of data coupled with low- cost equipment costs is only possible when the technology has proven reliable, in terms of application results, financial risks and data supply. Each of these factors is reviewed. The expectation is that international cooperation between agencies and private ventures will pave the way for future business models. As an illustration, the presentation proposes to use some recent non-traditional monitoring applications, that may lead to significant use of earth observation data, value added products and services: flood monitoring, ship detection, marine oil pollution deterrent systems and rice acreage monitoring.

  4. Progress toward risk informed regulation

    SciTech Connect

    Rogers, K.C.

    1997-01-01

    For the last several years, the NRC, with encouragement from the industry, has been moving in the direction of risk informed regulation. This is consistent with the regulatory principle of efficiency, formally adopted by the Nuclear Regulatory Commission in 1991, which requires that regulatory activities be consistent with the degree of risk reduction they achieve. Probabilistic risk analysis has become the tool of choice for selecting the best of several alternatives. Closely related to risk informed regulation is the development of performance based rules. Such rules focus on the end result to be achieved. They do not specify the process, but instead establish the goals to be reached and how the achievement of those goals is to be judged. The inspection and enforcement activity is based on whether or not the goals have been met. The author goes on to offer comments on the history of the development of this process and its probable development in the future. He also addresses some issues which must be resolved or at least acknowledged. The success of risk informed regulation ultimately depends on having sufficiently reliable data to allow quantification of regulatory alternatives in terms of relative risk. Perhaps the area of human reliability and organizational performance has the greatest potential for improvement in reactor safety. The ability to model human performance is significantly less developed that the ability to model mechanical or electrical systems. The move toward risk informed, performance based regulation provides an unusual, perhaps unique, opportunity to establish a more rational, more effective basis for regulation.

  5. Asymmetric Programming: A Highly Reliable Metadata Allocation Strategy for MLC NAND Flash Memory-Based Sensor Systems

    PubMed Central

    Huang, Min; Liu, Zhaoqing; Qiao, Liyan

    2014-01-01

    While the NAND flash memory is widely used as the storage medium in modern sensor systems, the aggressive shrinking of process geometry and an increase in the number of bits stored in each memory cell will inevitably degrade the reliability of NAND flash memory. In particular, it's critical to enhance metadata reliability, which occupies only a small portion of the storage space, but maintains the critical information of the file system and the address translations of the storage system. Metadata damage will cause the system to crash or a large amount of data to be lost. This paper presents Asymmetric Programming, a highly reliable metadata allocation strategy for MLC NAND flash memory storage systems. Our technique exploits for the first time the property of the multi-page architecture of MLC NAND flash memory to improve the reliability of metadata. The basic idea is to keep metadata in most significant bit (MSB) pages which are more reliable than least significant bit (LSB) pages. Thus, we can achieve relatively low bit error rates for metadata. Based on this idea, we propose two strategies to optimize address mapping and garbage collection. We have implemented Asymmetric Programming on a real hardware platform. The experimental results show that Asymmetric Programming can achieve a reduction in the number of page errors of up to 99.05% with the baseline error correction scheme. PMID:25310473

  6. Wikipedia : its reliability and social role

    NASA Astrophysics Data System (ADS)

    Kusaka, Kyuhachi

    This article discusses Japanese Wikipedia's reliability and its social role as a free, collaborative, multilingual Internet encyclopedia supported by the non-profit Wikimedia Foundation. Japanese Wikipedia's reliability is explained from several surveys. The central concern is how the nature of encyclopedia and Wikipedia affects the quality of Wikipedia's articles. Wikipedia's core content policies such as verifiability, no original research and a neutral point of view will make articles better. But incomplete or poorly written first drafts exist because Wikipedia is a work in progress. The article also argues that social role of online encyclopedia which provides knowledge for all. Knowledge-based society or/and advanced information society require public understanding of science and other expertise. Online encyclopedia attributed to a reliable, published source using an inline citation will guide anyone to specialized knowledge.

  7. [Achievement of therapeutic objectives].

    PubMed

    Mantilla, Teresa

    2014-07-01

    Therapeutic objectives for patients with atherogenic dyslipidemia are achieved by improving patient compliance and adherence. Clinical practice guidelines address the importance of treatment compliance for achieving objectives. The combination of a fixed dose of pravastatin and fenofibrate increases the adherence by simplifying the drug regimen and reducing the number of daily doses. The good tolerance, the cost of the combination and the possibility of adjusting the administration to the patient's lifestyle helps achieve the objectives for these patients with high cardiovascular risk. PMID:25043543

  8. 75 FR 81157 - Version One Regional Reliability Standard for Transmission Operations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... requests additional information. The Commission also proposes to direct WECC to develop certain limited.... FOR FURTHER INFORMATION CONTACT: Mindi Sauter (Legal Information), Office of the General Counsel... Henery (Technical Information), Office of Electric Reliability, Division of Policy Analysis...

  9. Bioharness™ Multivariable Monitoring Device: Part. II: Reliability

    PubMed Central

    Johnstone, James A.; Ford, Paul A.; Hughes, Gerwyn; Watson, Tim; Garrett, Andrew T.

    2012-01-01

    The Bioharness™ monitoring system may provide physiological information on human performance but the reliability of this data is fundamental for confidence in the equipment being used. The objective of this study was to assess the reliability of each of the 5 Bioharness™ variables using a treadmill based protocol. 10 healthy males participated. A between and within subject design to assess the reliability of Heart rate (HR), Breathing Frequency (BF), Accelerometry (ACC) and Infra-red skin temperature (ST) was completed via a repeated, discontinuous, incremental treadmill protocol. Posture (P) was assessed by a tilt table, moved through 160°. Between subject data reported low Coefficient of Variation (CV) and strong correlations(r) for ACC and P (CV< 7.6; r = 0.99, p < 0.01). In contrast, HR and BF (CV~19.4; r~0.70, p < 0.01) and ST (CV 3.7; r = 0.61, p < 0.01), present more variable data. Intra and inter device data presented strong relationships (r > 0.89, p < 0.01) and low CV (<10.1) for HR, ACC, P and ST. BF produced weaker relationships (r < 0.72) and higher CV (<17.4). In comparison to the other variables BF variable consistently presents less reliability. Global results suggest that the Bioharness™ is a reliable multivariable monitoring device during laboratory testing within the limits presented. Key pointsHeart rate and breathing frequency data increased in variance at higher velocities (i.e. ≥ 10 km.h-1)In comparison to the between subject testing, the intra and inter reliability presented good reliability in data suggesting placement or position of device relative to performer could be important for data collectionUnderstanding a devices variability in measurement is important before it can be used within an exercise testing or monitoring setting PMID:24149347

  10. Predicting Achievement and Motivation.

    ERIC Educational Resources Information Center

    Uguroglu, Margaret; Walberg, Herbert J.

    1986-01-01

    Motivation and nine other factors were measured for 970 students in grades five through eight in a study of factors predicting achievement and predicting motivation. Results are discussed. (Author/MT)

  11. Attractiveness and School Achievement

    ERIC Educational Resources Information Center

    Salvia, John; And Others

    1977-01-01

    The purpose of this study was to ascertain the relationship between rated attractiveness and two measures of school performance. Attractive children received significantly higher report cards and, to some degree, higher achievement test scores than their unattractive peers. (Author)

  12. Student Achievement and Motivation

    ERIC Educational Resources Information Center

    Flammer, Gordon H.; Mecham, Robert C.

    1974-01-01

    Compares the lecture and self-paced methods of instruction on the basis of student motivation and achieveme nt, comparing motivating and demotivating factors in each, and their potential for motivation and achievement. (Authors/JR)

  13. Culture Representation in Human Reliability Analysis

    SciTech Connect

    David Gertman; Julie Marble; Steven Novack

    2006-12-01

    Understanding human-system response is critical to being able to plan and predict mission success in the modern battlespace. Commonly, human reliability analysis has been used to predict failures of human performance in complex, critical systems. However, most human reliability methods fail to take culture into account. This paper takes an easily understood state of the art human reliability analysis method and extends that method to account for the influence of culture, including acceptance of new technology, upon performance. The cultural parameters used to modify the human reliability analysis were determined from two standard industry approaches to cultural assessment: Hofstede’s (1991) cultural factors and Davis’ (1989) technology acceptance model (TAM). The result is called the Culture Adjustment Method (CAM). An example is presented that (1) reviews human reliability assessment with and without cultural attributes for a Supervisory Control and Data Acquisition (SCADA) system attack, (2) demonstrates how country specific information can be used to increase the realism of HRA modeling, and (3) discusses the differences in human error probability estimates arising from cultural differences.

  14. Tutorial: Performance and reliability in redundant disk arrays

    NASA Technical Reports Server (NTRS)

    Gibson, Garth A.

    1993-01-01

    A disk array is a collection of physically small magnetic disks that is packaged as a single unit but operates in parallel. Disk arrays capitalize on the availability of small-diameter disks from a price-competitive market to provide the cost, volume, and capacity of current disk systems but many times their performance. Unfortunately, relative to current disk systems, the larger number of components in disk arrays leads to higher rates of failure. To tolerate failures, redundant disk arrays devote a fraction of their capacity to an encoding of their information. This redundant information enables the contents of a failed disk to be recovered from the contents of non-failed disks. The simplest and least expensive encoding for this redundancy, known as N+1 parity is highlighted. In addition to compensating for the higher failure rates of disk arrays, redundancy allows highly reliable secondary storage systems to be built much more cost-effectively than is now achieved in conventional duplicated disks. Disk arrays that combine redundancy with the parallelism of many small-diameter disks are often called Redundant Arrays of Inexpensive Disks (RAID). This combination promises improvements to both the performance and the reliability of secondary storage. For example, IBM's premier disk product, the IBM 3390, is compared to a redundant disk array constructed of 84 IBM 0661 3 1/2-inch disks. The redundant disk array has comparable or superior values for each of the metrics given and appears likely to cost less. In the first section of this tutorial, I explain how disk arrays exploit the emergence of high performance, small magnetic disks to provide cost-effective disk parallelism that combats the access and transfer gap problems. The flexibility of disk-array configurations benefits manufacturer and consumer alike. In contrast, I describe in this tutorial's second half how parallelism, achieved through increasing numbers of components, causes overall failure rates to rise

  15. Developing Ultra Reliable Life Support for the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Jones, Harry W.

    2009-01-01

    Recycling life support systems can achieve ultra reliability by using spares to replace failed components. The added mass for spares is approximately equal to the original system mass, provided the original system reliability is not very low. Acceptable reliability can be achieved for the space shuttle and space station by preventive maintenance and by replacing failed units, However, this maintenance and repair depends on a logistics supply chain that provides the needed spares. The Mars mission must take all the needed spares at launch. The Mars mission also must achieve ultra reliability, a very low failure rate per hour, since it requires years rather than weeks and cannot be cut short if a failure occurs. Also, the Mars mission has a much higher mass launch cost per kilogram than shuttle or station. Achieving ultra reliable space life support with acceptable mass will require a well-planned and extensive development effort. Analysis must define the reliability requirement and allocate it to subsystems and components. Technologies, components, and materials must be designed and selected for high reliability. Extensive testing is needed to ascertain very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The systems must be designed, produced, integrated, and tested without impairing system reliability. Maintenance and failed unit replacement should not introduce any additional probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass must start soon if it is to produce timely results for the moon and Mars.

  16. Coefficient Alpha: A Reliability Coefficient for the 21st Century?

    ERIC Educational Resources Information Center

    Yang, Yanyun; Green, Samuel B.

    2011-01-01

    Coefficient alpha is almost universally applied to assess reliability of scales in psychology. We argue that researchers should consider alternatives to coefficient alpha. Our preference is for structural equation modeling (SEM) estimates of reliability because they are informative and allow for an empirical evaluation of the assumptions…

  17. Reliability of the Revised Psychopathy Checklist in Substance Abuse Patients.

    ERIC Educational Resources Information Center

    Alterman, Arthur I.; And Others

    1993-01-01

    One month test-retest reliability of the Revised Psychopathy Checklist (PCL-R) was examined in 88 methadone-maintained males, along with effects of increased information about patients on PCL-R scores and diagnostic derivations. Test-retest reliabilities are quite good. Other findings also confirm potential utility of the PCL-R for research. (SLD)

  18. Reliability-aware iterative detection scheme (RAID) for distributed IDM space-time codes in relay systems

    NASA Astrophysics Data System (ADS)

    Lenkeit, Florian; Wübben, Dirk; Dekorsy, Armin

    2013-12-01

    In this article, distributed interleave-division multiplexing space-time codes (dIDM-STCs) are applied for multi-user two-hop decode-and-forward (DF) relay networks. In case of decoding errors at the relays which propagate to the destination, severe performance degradations can occur as the original detection scheme for common IDM-STCs does not take any reliability information about the first hop into account. Here, a novel reliability-aware iterative detection scheme (RAID) for dIDM-STCs is proposed. This new detection scheme takes the decoding reliability of the relays for each user into account for the detection at the destination. Performance evaluations show that the proposed RAID scheme clearly outperforms the original detection scheme and that in certain scenarios even a better performance than for adaptive relaying schemes can be achieved.

  19. Program for Area Concentration Achievement Testing.

    ERIC Educational Resources Information Center

    Golden, Anthony J.

    The Program for Area Concentration Achievement Testing (PACAT) produces the cooperative assessment instrument known as the Area Concentration Achievement Test (ACAT). The ACAT uses a model designed specifically to measure curricular strengths and weaknesses and to provide this information at the departmental level. PACAT has developed 57…

  20. Type A Performance Standards and Goal Achievement.

    ERIC Educational Resources Information Center

    Ward, Clay H.

    Achievement striving is a central dimension of the Type A behavior pattern. To investigate the relationship between Type A behavior pattern, personal performance goals, and goal achievement on two general information tests, 126 undergraduates participated in a two-phase study. First, behavior patterns were assessed using the Framingham Type A…

  1. Reliability prediction for evolutionary product in the conceptual design phase using neural network-based fuzzy synthetic assessment

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Huang, Hong-Zhong; Ling, Dan

    2013-03-01

    Reliability prediction plays an important role in product lifecycle management. It has been used to assess various reliability indices (such as reliability, availability and mean time to failure) before a new product is physically built and/or put into use. In this article, a novel approach is proposed to facilitate reliability prediction for evolutionary products during their early design stages. Due to the lack of sufficient data in the conceptual design phase, reliability prediction is not a straightforward task. Taking account of the information from existing similar products and knowledge from domain experts, a neural network-based fuzzy synthetic assessment (FSA) approach is proposed to predict the reliability indices that a new evolutionary product could achieve. The proposed approach takes advantage of the capability of the back-propagation neural network in terms of constructing highly non-linear functional relationship and combines both the data sets from existing similar products and subjective knowledge from domain experts. It is able to reach a more accurate prediction than the conventional FSA method reported in the literature. The effectiveness and advantages of the proposed method are demonstrated via a case study of the fuel injection pump and a comparative study.

  2. Bandwidth efficient coding: Theoretical limits and real achievements. Error control techniques for satellite and space communications

    NASA Technical Reports Server (NTRS)

    Costello, Daniel J., Jr.; Courturier, Servanne; Levy, Yannick; Mills, Diane G.; Perez, Lance C.; Wang, Fu-Quan

    1993-01-01

    In his seminal 1948 paper 'The Mathematical Theory of Communication,' Claude E. Shannon derived the 'channel coding theorem' which has an explicit upper bound, called the channel capacity, on the rate at which 'information' could be transmitted reliably on a given communication channel. Shannon's result was an existence theorem and did not give specific codes to achieve the bound. Some skeptics have claimed that the dramatic performance improvements predicted by Shannon are not achievable in practice. The advances made in the area of coded modulation in the past decade have made communications engineers optimistic about the possibility of achieving or at least coming close to channel capacity. Here we consider the possibility in the light of current research results.

  3. A Statistical Approach to Characterizing the Reliability of Systems Utilizing HBT Devices

    NASA Technical Reports Server (NTRS)

    Chen, Yuan; Wang, Qing; Kayali, Sammy

    2004-01-01

    This paper presents a statistical approach to characterizing the reliability of systems with HBT devices. The proposed approach utilizes the statistical reliability information of the HBT individual devices, along with the analysis on the critical paths of the system, to provide more accurate and more comprehensive reliability information about the HBT systems compared to the conventional worst-case method.

  4. Reliability of wireless sensor networks.

    PubMed

    Dâmaso, Antônio; Rosa, Nelson; Maciel, Paulo

    2014-01-01

    Wireless Sensor Networks (WSNs) consist of hundreds or thousands of sensor nodes with limited processing, storage, and battery capabilities. There are several strategies to reduce the power consumption of WSN nodes (by increasing the network lifetime) and increase the reliability of the network (by improving the WSN Quality of Service). However, there is an inherent conflict between power consumption and reliability: an increase in reliability usually leads to an increase in power consumption. For example, routing algorithms can send the same packet though different paths (multipath strategy), which it is important for reliability, but they significantly increase the WSN power consumption. In this context, this paper proposes a model for evaluating the reliability of WSNs considering the battery level as a key factor. Moreover, this model is based on routing algorithms used by WSNs. In order to evaluate the proposed models, three scenarios were considered to show the impact of the power consumption on the reliability of WSNs. PMID:25157553

  5. Nuclear weapon reliability evaluation methodology

    SciTech Connect

    Wright, D.L.

    1993-06-01

    This document provides an overview of those activities that are normally performed by Sandia National Laboratories to provide nuclear weapon reliability evaluations for the Department of Energy. These reliability evaluations are first provided as a prediction of the attainable stockpile reliability of a proposed weapon design. Stockpile reliability assessments are provided for each weapon type as the weapon is fielded and are continuously updated throughout the weapon stockpile life. The reliability predictions and assessments depend heavily on data from both laboratory simulation and actual flight tests. An important part of the methodology are the opportunities for review that occur throughout the entire process that assure a consistent approach and appropriate use of the data for reliability evaluation purposes.

  6. SAFE Alkali Metal Heat Pipe Reliability

    NASA Astrophysics Data System (ADS)

    Reid, Robert S.

    2003-01-01

    Alkali metal heat pipes are among the best understood and tested of components for first generation space fission reactors. A flight reactor will require production of a hundred or more heat pipes with assured reliability over a number of years. To date, alkali metal heat pipes have been built mostly in low budget development environments with little formal quality assurance. Despite this, heat pipe test samples suggest that high reliability can be achieved with the care justified for space flight qualification. Fabrication procedures have been established that, if consistently applied, ensure long-term trouble-free heat pipe operation. Alkali metal heat pipes have been successfully flight tested in micro gravity and also have been shown capable of multi-year operation with no evidence of sensitivity to fast neutron fluence up to 1023 n/cm2. This represents 50 times the fluence of the proposed Safe Affordable Fission Engine (SAFE-100) heat pipe reactor core.

  7. Probabilistic Methods for Structural Design and Reliability

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.; Whitlow, Woodrow, Jr. (Technical Monitor)

    2002-01-01

    This report describes a formal method to quantify structural damage tolerance and reliability in the presence of a multitude of uncertainties in turbine engine components. The method is based at the material behavior level where primitive variables with their respective scatter ranges are used to describe behavior. Computational simulation is then used to propagate the uncertainties to the structural scale where damage tolerance and reliability are usually specified. Several sample cases are described to illustrate the effectiveness, versatility, and maturity of the method. Typical results from this method demonstrate, that it is mature and that it can be used to probabilistically evaluate turbine engine structural components. It may be inferred from the results that the method is suitable for probabilistically predicting the remaining life in aging or in deteriorating structures, for making strategic projections and plans, and for achieving better, cheaper, faster products that give competitive advantages in world markets.

  8. Optimal Implementations for Reliable Circadian Clocks

    NASA Astrophysics Data System (ADS)

    Hasegawa, Yoshihiko; Arita, Masanori

    2014-09-01

    Circadian rhythms are acquired through evolution to increase the chances for survival through synchronizing with the daylight cycle. Reliable synchronization is realized through two trade-off properties: regularity to keep time precisely, and entrainability to synchronize the internal time with daylight. We find by using a phase model with multiple inputs that achieving the maximal limit of regularity and entrainability entails many inherent features of the circadian mechanism. At the molecular level, we demonstrate the role sharing of two light inputs, phase advance and delay, as is well observed in mammals. At the behavioral level, the optimal phase-response curve inevitably contains a dead zone, a time during which light pulses neither advance nor delay the clock. We reproduce the results of phase-controlling experiments entrained by two types of periodic light pulses. Our results indicate that circadian clocks are designed optimally for reliable clockwork through evolution.

  9. Building a Reliable Onboard Network with Ethernet: A GSFC Prototype

    NASA Technical Reports Server (NTRS)

    Marquart, Jane

    2004-01-01

    This viewgraph presentation discusses the architecture of an Ethernet-based communication network for spacecraft. The presentation also contains information on data link reliability, PDU formats, and NIC/OS Measurements.

  10. Confirmatory Factor Analysis of Achieving the Beginning Teacher Standards Inventory

    ERIC Educational Resources Information Center

    Chen, Weiyun

    2009-01-01

    The purpose of this study was to examine the factorial validity and reliability of the "Achieving the NASPE Standards Inventory (ANSI)" that assesses pre-service physical education teachers' perceptions of achieving the National Association for Sport and Physical Education (NASPE) beginning teacher standards (2003). Four hundred fifty-two…

  11. A fourth generation reliability predictor

    NASA Technical Reports Server (NTRS)

    Bavuso, Salvatore J.; Martensen, Anna L.

    1988-01-01

    A reliability/availability predictor computer program has been developed and is currently being beta-tested by over 30 US companies. The computer program is called the Hybrid Automated Reliability Predictor (HARP). HARP was developed to fill an important gap in reliability assessment capabilities. This gap was manifested through the use of its third-generation cousin, the Computer-Aided Reliability Estimation (CARE III) program, over a six-year development period and an additional three-year period during which CARE III has been in the public domain. The accumulated experience of the over 30 establishments now using CARE III was used in the development of the HARP program.

  12. US electric power system reliability

    NASA Astrophysics Data System (ADS)

    Electric energy supply, transmission and distribution systems are investigated in order to determine priorities for legislation. The status and the outlook for electric power reliability are discussed.

  13. Nuclear electric propulsion operational reliability and crew safety study: NEP systems/modeling report

    NASA Technical Reports Server (NTRS)

    Karns, James

    1993-01-01

    The objective of this study was to establish the initial quantitative reliability bounds for nuclear electric propulsion systems in a manned Mars mission required to ensure crew safety and mission success. Finding the reliability bounds involves balancing top-down (mission driven) requirements and bottom-up (technology driven) capabilities. In seeking this balance we hope to accomplish the following: (1) provide design insights into the achievability of the baseline design in terms of reliability requirements, given the existing technology base; (2) suggest alternative design approaches which might enhance reliability and crew safety; and (3) indicate what technology areas require significant research and development to achieve the reliability objectives.

  14. Reliable Delay Constrained Multihop Broadcasting in VANETs

    NASA Astrophysics Data System (ADS)

    Koubek, Martin; Rea, Susan; Pesch, Dirk

    2010-12-01

    Vehicular communication is regarded as a major innovative feature for in-car technology. While improving road safety is unanimously considered the major driving factor for the deployment of Intelligent Vehicle Safety Systems, the challenges relating to reliable multi-hop broadcasting are exigent in vehicular networking. In fact, safety applications must rely on very accurate and up-to-date information about the surrounding environment, which in turn requires the use of accurate positioning systems and smart communication protocols for exchanging information. Communications protocols for VANETs must guarantee fast and reliable delivery of information to all vehicles in the neighbourhood, where the wireless communication medium is shared and highly unreliable with limited bandwidth. In this paper, we focus on mechanisms that improve the reliability of broadcasting protocols, where the emphasis is on satisfying the delay requirements for safety applications. We present the Pseudoacknowledgments (PACKs) scheme and compare this with existing methods over varying vehicle densities in an urban scenario using the network simulator OPNET.

  15. Reliable Wireless Broadcast with Linear Network Coding for Multipoint-to-Multipoint Real-Time Communications

    NASA Astrophysics Data System (ADS)

    Kondo, Yoshihisa; Yomo, Hiroyuki; Yamaguchi, Shinji; Davis, Peter; Miura, Ryu; Obana, Sadao; Sampei, Seiichi

    This paper proposes multipoint-to-multipoint (MPtoMP) real-time broadcast transmission using network coding for ad-hoc networks like video game networks. We aim to achieve highly reliable MPtoMP broadcasting using IEEE 802.11 media access control (MAC) that does not include a retransmission mechanism. When each node detects packets from the other nodes in a sequence, the correctly detected packets are network-encoded, and the encoded packet is broadcasted in the next sequence as a piggy-back for its native packet. To prevent increase of overhead in each packet due to piggy-back packet transmission, network coding vector for each node is exchanged between all nodes in the negotiation phase. Each user keeps using the same coding vector generated in the negotiation phase, and only coding information that represents which user signal is included in the network coding process is transmitted along with the piggy-back packet. Our simulation results show that the proposed method can provide higher reliability than other schemes using multi point relay (MPR) or redundant transmissions such as forward error correction (FEC). We also implement the proposed method in a wireless testbed, and show that the proposed method achieves high reliability in a real-world environment with a practical degree of complexity when installed on current wireless devices.

  16. Reliability and coverage analysis of non-repairable fault-tolerant memory systems

    NASA Technical Reports Server (NTRS)

    Cox, G. W.; Carroll, B. D.

    1976-01-01

    A method was developed for the construction of probabilistic state-space models for nonrepairable systems. Models were developed for several systems which achieved reliability improvement by means of error-coding, modularized sparing, massive replication and other fault-tolerant techniques. From the models developed, sets of reliability and coverage equations for the systems were developed. Comparative analyses of the systems were performed using these equation sets. In addition, the effects of varying subunit reliabilities on system reliability and coverage were described. The results of these analyses indicated that a significant gain in system reliability may be achieved by use of combinations of modularized sparing, error coding, and software error control. For sufficiently reliable system subunits, this gain may far exceed the reliability gain achieved by use of massive replication techniques, yet result in a considerable saving in system cost.

  17. Reliability analysis and optimization in the design of distributed systems

    SciTech Connect

    Hariri, S.

    1986-01-01

    Reliability measures and efficient evaluation algorithms are presented to aid in designing reliable distributed systems. The terminal reliability between a pair of computers is a good measure in computer networks. For distributed systems, to capture more effectively the redundancy in resources, such as programs and files, two new reliability measures are introduced. These measures are Distributed Program Reliability (DPR) and Distributed System Reliability (DSR). A simple and efficient algorithm, SYREL, is developed to evaluate the reliability between two computing centers. This algorithm incorporates conditional probability, set theory, and Boolean algebra in a distinct approach to achieve fast execution times and obtain compact expressions. An elegant and unified approach based on graph-theoretic techniques is used in developing algorithms to evaluate DPR and DSR measures. It performs a breadth-first search on the graph representing a given distributed system to enumerate all the subgraphs that guarantee the proper accessibility for executing the given tasks(s). These subgraphs are then used to evaluate the desired reliabilities. Several optimization algorithms are developed for designing reliable systems under a cost constraint.

  18. Survey of Software Assurance Techniques for Highly Reliable Systems

    NASA Technical Reports Server (NTRS)

    Nelson, Stacy

    2004-01-01

    This document provides a survey of software assurance techniques for highly reliable systems including a discussion of relevant safety standards for various industries in the United States and Europe, as well as examples of methods used during software development projects. It contains one section for each industry surveyed: Aerospace, Defense, Nuclear Power, Medical Devices and Transportation. Each section provides an overview of applicable standards and examples of a mission or software development project, software assurance techniques used and reliability achieved.

  19. The process group approach to reliable distributed computing

    NASA Technical Reports Server (NTRS)

    Birman, Kenneth P.

    1992-01-01

    The difficulty of developing reliable distribution software is an impediment to applying distributed computing technology in many settings. Experience with the ISIS system suggests that a structured approach based on virtually synchronous process groups yields systems that are substantially easier to develop, exploit sophisticated forms of cooperative computation, and achieve high reliability. Six years of research on ISIS, describing the model, its implementation challenges, and the types of applications to which ISIS has been applied are reviewed.

  20. Reliability of large superconducting magnets through design

    SciTech Connect

    Henning, C.D.

    1980-09-05

    As superconducting magnet systems grow larger and become the central component of major systems involving fusion, magnetohydrodynamics, and high-energy physics, their reliability must be commensurate with the enormous capital investment in the projects. Although the magnet may represent only 15% of the cost of a large system such as the Mirror Fusion Test Facility, its failure would be catastrophic to the entire investment. Effective quality control during construction is one method of ensuring success. However, if the design is unforgiving, even an inordinate amount of effort expended on quality control may be inadequate. Creative design is the most effective way of ensuring magnet reliability and providing a reasonable limit on the amount of quality control needed. For example, by subjecting the last drawing operation is superconductor manufacture to a stress larger than the magnet design stress, a 100% proof test is achieved; cabled conductors offer mechanical redundancy, as do some methods of conductor joining; ground-plane insulation should be multilayered to prevent arcs, and interturn and interlayer insulation spaced to be compatible with the self-extinguishing of arcs during quench voltages; electrical leads should be thermally protected; and guard vacuum spaces can be incorporated to control helium leaks. Many reliable design options are known to magnet designers. These options need to be documented and organized to produce a design guide. Eventually, standard procedures, safety factors, and design codes can lead to reliability in magnets comparable to that obtained in pressure vessels and other structures. Wihout such reliability, large-scale applications in major systems employing magnetic fusion energy, magnetohydrodynamics, or high-energy physics would present unacceptable economic risks.

  1. Explorations in achievement motivation

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.

    1982-01-01

    Recent research on the nature of achievement motivation is reviewed. A three-factor model of intrinsic motives is presented and related to various criteria of performance, job satisfaction and leisure activities. The relationships between intrinsic and extrinsic motives are discussed. Needed areas for future research are described.

  2. Achieving health care affordability.

    PubMed

    Payson, Norman C

    2002-10-01

    Not all plans are jumping headlong into the consumer-centric arena. In this article, the CEO of Oxford Health Plans discusses how advanced managed care can achieve what other consumer-centric programs seek to do--provide affordable, quality health care. PMID:12391815

  3. Issues in Achievement Testing.

    ERIC Educational Resources Information Center

    Baker, Eva L.

    This booklet is intended to help school personnel, parents, students, and members of the community understand concepts and research relating to achievement testing in public schools. The paper's sections include: (1) test use with direct effects on students (test of certification, selection, and placement); (2) test use with indirect effects on…

  4. Achieving Peace through Education.

    ERIC Educational Resources Information Center

    Clarken, Rodney H.

    While it is generally agreed that peace is desirable, there are barriers to achieving a peaceful world. These barriers are classified into three major areas: (1) an erroneous view of human nature; (2) injustice; and (3) fear of world unity. In a discussion of these barriers, it is noted that although the consciousness and conscience of the world…

  5. Achieving All Our Ambitions

    ERIC Educational Resources Information Center

    Hartley, Tricia

    2009-01-01

    National learning and skills policy aims both to build economic prosperity and to achieve social justice. Participation in higher education (HE) has the potential to contribute substantially to both aims. That is why the Campaign for Learning has supported the ambition to increase the proportion of the working-age population with a Level 4…

  6. Intelligence and Educational Achievement

    ERIC Educational Resources Information Center

    Deary, Ian J.; Strand, Steve; Smith, Pauline; Fernandes, Cres

    2007-01-01

    This 5-year prospective longitudinal study of 70,000+ English children examined the association between psychometric intelligence at age 11 years and educational achievement in national examinations in 25 academic subjects at age 16. The correlation between a latent intelligence trait (Spearman's "g"from CAT2E) and a latent trait of educational…

  7. SALT and Spelling Achievement.

    ERIC Educational Resources Information Center

    Nelson, Joan

    A study investigated the effects of suggestopedic accelerative learning and teaching (SALT) on the spelling achievement, attitudes toward school, and memory skills of fourth-grade students. Subjects were 20 male and 28 female students from two self-contained classrooms at Kennedy Elementary School in Rexburg, Idaho. The control classroom and the…

  8. NCLB: Achievement Robin Hood?

    ERIC Educational Resources Information Center

    Bracey, Gerald W.

    2008-01-01

    In his "Wall Street Journal" op-ed on the 25th of anniversary of "A Nation At Risk", former assistant secretary of education Chester E. Finn Jr. applauded the report for turning U.S. education away from equality and toward achievement. It was not surprising, then, that in mid-2008, Finn arranged a conference to examine the potential "Robin Hood…

  9. INTELLIGENCE, PERSONALITY AND ACHIEVEMENT.

    ERIC Educational Resources Information Center

    MUIR, R.C.; AND OTHERS

    A LONGITUDINAL DEVELOPMENTAL STUDY OF A GROUP OF MIDDLE CLASS CHILDREN IS DESCRIBED, WITH EMPHASIS ON A SEGMENT OF THE RESEARCH INVESTIGATING THE RELATIONSHIP OF ACHIEVEMENT, INTELLIGENCE, AND EMOTIONAL DISTURBANCE. THE SUBJECTS WERE 105 CHILDREN AGED FIVE TO 6.3 ATTENDING TWO SCHOOLS IN MONTREAL. EACH CHILD WAS ASSESSED IN THE AREAS OF…

  10. School Students' Science Achievement

    ERIC Educational Resources Information Center

    Shymansky, James; Wang, Tzu-Ling; Annetta, Leonard; Everett, Susan; Yore, Larry D.

    2013-01-01

    This paper is a report of the impact of an externally funded, multiyear systemic reform project on students' science achievement on a modified version of the Third International Mathematics and Science Study (TIMSS) test in 33 small, rural school districts in two Midwest states. The systemic reform effort utilized a cascading leadership strategy…

  11. Essays on Educational Achievement

    ERIC Educational Resources Information Center

    Ampaabeng, Samuel Kofi

    2013-01-01

    This dissertation examines the determinants of student outcomes--achievement, attainment, occupational choices and earnings--in three different contexts. The first two chapters focus on Ghana while the final chapter focuses on the US state of Massachusetts. In the first chapter, I exploit the incidence of famine and malnutrition that resulted to…

  12. Increasing Male Academic Achievement

    ERIC Educational Resources Information Center

    Jackson, Barbara Talbert

    2008-01-01

    The No Child Left Behind legislation has brought greater attention to the academic performance of American youth. Its emphasis on student achievement requires a closer analysis of assessment data by school districts. To address the findings, educators must seek strategies to remedy failing results. In a mid-Atlantic district of the Unites States,…

  13. Setting and Achieving Objectives.

    ERIC Educational Resources Information Center

    Knoop, Robert

    1986-01-01

    Provides basic guidelines which school officials and school boards may find helpful in negotiating, establishing, and managing objectives. Discusses characteristics of good objectives, specific and directional objectives, multiple objectives, participation in setting objectives, feedback on goal process and achievement, and managing a school…

  14. Schools Achieving Gender Equity.

    ERIC Educational Resources Information Center

    Revis, Emma

    This guide is designed to assist teachers presenting the Schools Achieving Gender Equity (SAGE) curriculum for vocational education students, which was developed to align gender equity concepts with the Kentucky Education Reform Act (KERA). Included in the guide are lesson plans for classes on the following topics: legal issues of gender equity,…

  15. Iowa Women of Achievement.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This issue of the Goldfinch highlights some of Iowa's 20th century women of achievement. These women have devoted their lives to working for human rights, education, equality, and individual rights. They come from the worlds of politics, art, music, education, sports, business, entertainment, and social work. They represent Native Americans,…

  16. Achievements or Disasters?

    ERIC Educational Resources Information Center

    Goodwin, MacArthur

    2000-01-01

    Focuses on policy issues that have affected arts education in the twentieth century, such as: interest in discipline-based arts education, influence of national arts associations, and national standards and coordinated assessment. States that whether the policy decisions are viewed as achievements or disasters are for future determination. (CMK)

  17. Minority Achievement Report.

    ERIC Educational Resources Information Center

    Prince George's Community Coll., Largo, MD. Office of Institutional Research and Analysis.

    This report summarizes the achievements of Prince George's Community College (PGCC) with regard to minority outcomes. Table 1 summarizes the undergraduate enrollment trends for African Americans as well as total minorities from fall 1994 through fall 1998. Both the headcount number of African American students and the proportion of African…

  18. Appraising Reading Achievement.

    ERIC Educational Resources Information Center

    Ediger, Marlow

    To determine quality sequence in pupil progress, evaluation approaches need to be used which guide the teacher to assist learners to attain optimally. Teachers must use a variety of procedures to appraise student achievement in reading, because no one approach is adequate. Appraisal approaches might include: (1) observation and subsequent…

  19. A reliability evaluation methodology for memory chips for space applications when sample size is small

    NASA Technical Reports Server (NTRS)

    Chen, Y.; Nguyen, D.; Guertin, S.; Berstein, J.; White, M.; Menke, R.; Kayali, S.

    2003-01-01

    This paper presents a reliability evaluation methodology to obtain the statistical reliability information of memory chips for space applications when the test sample size needs to be kept small because of the high cost of the radiation hardness memories.

  20. Reliability and validity of a tool to assess airway management skills in anesthesia trainees

    PubMed Central

    Ahmed, Aliya; Khan, Fauzia Anis; Ismail, Samina

    2016-01-01

    Background and Aims: Gaining expertise in procedural skills is essential for achieving clinical competence during anesthesia training. Supervisors have the important responsibility of deciding when the trainee can be allowed to perform various procedures without direct supervision while ensuring patient safety. This requires robust and reliable assessment techniques. Airway management with bag-mask ventilation and tracheal intubation are routinely performed by anesthesia trainees at induction of anesthesia and to save lives during a cardiorespiratory arrest. The purpose of this study was to evaluate the construct validity, and inter-rater and test-retest reliability of a tool designed to assess competence in bag-mask ventilation followed by tracheal intubation in anesthesia trainees. Material and Methods: Informed consent was obtained from all participants. Tracheal intubation and bag-mask ventilation skills in 10 junior and 10 senior anesthesia trainees were assessed by two investigators on two occasions at a 3-4 weeks interval, using a procedure-specific assessment tool. Results: Average kappa value for inter-rater reliability was 0.91 and 0.99 for the first and second assessments, respectively, with an average agreement of 95%. The average agreement for test-retest reliability was 82% with a kappa value of 0.39. Senior trainees obtained higher scores compared to junior trainees in all areas of assessment, with a significant difference for patient positioning, preoxygenation, and laryngoscopy technique, depicting good construct validity. Conclusion: The tool designed to assess bag-mask ventilation and tracheal intubation skills in anesthesia trainees demonstrated excellent inter-rater reliability, fair test-retest reliability, and good construct validity. The authors recommend its use for formative and summative assessment of junior anesthesia trainees.

  1. Reliability Impacts in Life Support Architecture and Technology Selection

    NASA Technical Reports Server (NTRS)

    Lange Kevin E.; Anderson, Molly S.

    2012-01-01

    Quantitative assessments of system reliability and equivalent system mass (ESM) were made for different life support architectures based primarily on International Space Station technologies. The analysis was applied to a one-year deep-space mission. System reliability was increased by adding redundancy and spares, which added to the ESM. Results were thus obtained allowing a comparison of the ESM for each architecture at equivalent levels of reliability. Although the analysis contains numerous simplifications and uncertainties, the results suggest that achieving necessary reliabilities for deep-space missions will add substantially to the life support ESM and could influence the optimal degree of life support closure. Approaches for reducing reliability impacts were investigated and are discussed.

  2. The ATS F&G systems reliability program.

    NASA Technical Reports Server (NTRS)

    Doyle, H.

    1972-01-01

    Assurance of reliability, quality, and proper testing requires a large coordinating effort and a means for connecting the various areas involved. All parts used on the spacecraft are required to meet strict specifications and consequently must be approved by the systems reliability manager. The parts program has access to a computer data bank into which all information concerning nonstandard parts approval requests has been stored. Through the data bank, the system collects and distributes timely information concerning quality and reliability to all departments that may be concerned.

  3. NASA reliability preferred practices for design and test

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Given here is a manual that was produced to communicate within the aerospace community design practices that have contributed to NASA mission success. The information represents the best technical advice that NASA has to offer on reliability design and test practices. Topics covered include reliability practices, including design criteria, test procedures, and analytical techniques that have been applied to previous space flight programs; and reliability guidelines, including techniques currently applied to space flight projects, where sufficient information exists to certify that the technique will contribute to mission success.

  4. Reliable 6 PEP LTPS device for AMOLED's

    NASA Astrophysics Data System (ADS)

    Chou, Cheng-Wei; Wang, Pei-Yun; Hu, Chin-Wei; Chang, York; Chuang, Ching-Sang; Lin, Yusin

    2013-09-01

    This study presents a TFT structure which has less photo process and higher cost competitiveness in AMOLED display markets. A novel LTPS based 6 masks TFT structure for bottom emission AMOLED display is demonstrated in this paper. High field effect mobility (PMOS < 80 cm2/Vs ) and high reliability (PBTS △Vth< 0.02V @ 50oC VG=15V 10ks) was accomplished without the high temperature and rapid thermal annealing (RTA) activation process. Furthermore, a 14-inch AMOLED TV was achieved on the proposed 6-pep TFT backplane using the Gen. 3.5 mass production factory.

  5. Measuring eating disorder attitudes and behaviors: a reliability generalization study

    PubMed Central

    2014-01-01

    Background Although score reliability is a sample-dependent characteristic, researchers often only report reliability estimates from previous studies as justification for employing particular questionnaires in their research. The present study followed reliability generalization procedures to determine the mean score reliability of the Eating Disorder Inventory and its most commonly employed subscales (Drive for Thinness, Bulimia, and Body Dissatisfaction) and the Eating Attitudes Test as a way to better identify those characteristics that might impact score reliability. Methods Published studies that used these measures were coded based on their reporting of reliability information and additional study characteristics that might influence score reliability. Results Score reliability estimates were included in 26.15% of studies using the EDI and 36.28% of studies using the EAT. Mean Cronbach’s alphas for the EDI (total score = .91; subscales = .75 to .89), EAT-40 (total score = .81) and EAT-26 (total score = .86; subscales = .56 to .80) suggested variability in estimated internal consistency. Whereas some EDI subscales exhibited higher score reliability in clinical eating disorder samples than in nonclinical samples, other subscales did not exhibit these differences. Score reliability information for the EAT was primarily reported for nonclinical samples, making it difficult to characterize the effect of type of sample on these measures. However, there was a tendency for mean score reliability to be higher in the adult (vs. adolescent) samples and in female (vs. male) samples. Conclusions Overall, this study highlights the importance of assessing and reporting internal consistency during every test administration because reliability is affected by characteristics of the participants being examined. PMID:24764530

  6. Stirling Convertor Fasteners Reliability Quantification

    NASA Technical Reports Server (NTRS)

    Shah, Ashwin R.; Korovaichuk, Igor; Kovacevich, Tiodor; Schreiber, Jeffrey G.

    2006-01-01

    Onboard Radioisotope Power Systems (RPS) being developed for NASA s deep-space science and exploration missions require reliable operation for up to 14 years and beyond. Stirling power conversion is a candidate for use in an RPS because it offers a multifold increase in the conversion efficiency of heat to electric power and reduced inventory of radioactive material. Structural fasteners are responsible to maintain structural integrity of the Stirling power convertor, which is critical to ensure reliable performance during the entire mission. Design of fasteners involve variables related to the fabrication, manufacturing, behavior of fasteners and joining parts material, structural geometry of the joining components, size and spacing of fasteners, mission loads, boundary conditions, etc. These variables have inherent uncertainties, which need to be accounted for in the reliability assessment. This paper describes these uncertainties along with a methodology to quantify the reliability, and provides results of the analysis in terms of quantified reliability and sensitivity of Stirling power conversion reliability to the design variables. Quantification of the reliability includes both structural and functional aspects of the joining components. Based on the results, the paper also describes guidelines to improve the reliability and verification testing.

  7. Avionics design for reliability bibliography

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A bibliography with abstracts was presented in support of AGARD lecture series No. 81. The following areas were covered: (1) program management, (2) design for high reliability, (3) selection of components and parts, (4) environment consideration, (5) reliable packaging, (6) life cycle cost, and (7) case histories.

  8. Computer-Aided Reliability Estimation

    NASA Technical Reports Server (NTRS)

    Bavuso, S. J.; Stiffler, J. J.; Bryant, L. A.; Petersen, P. L.

    1986-01-01

    CARE III (Computer-Aided Reliability Estimation, Third Generation) helps estimate reliability of complex, redundant, fault-tolerant systems. Program specifically designed for evaluation of fault-tolerant avionics systems. However, CARE III general enough for use in evaluation of other systems as well.

  9. The Reliability of Density Measurements.

    ERIC Educational Resources Information Center

    Crothers, Charles

    1978-01-01

    Data from a land-use study of small- and medium-sized towns in New Zealand are used to ascertain the relationship between official and effective density measures. It was found that the reliability of official measures of density is very low overall, although reliability increases with community size. (Author/RLV)

  10. The impact of reliability on naval aviation operations

    NASA Astrophysics Data System (ADS)

    Lashbrooke, D. P.

    The Gulf war illustrated the effectiveness of Naval helicopters, as well as the impact of reliability on rapidly fitted new equipment. Poor reliability can lead to reduced effectiveness, inadequate spares, high cost, and increased risk to human life. Only limited improvements can be achieved in service so the Navy's Aircraft Support Executive has developed ways of targeting equipment having the most adverse effect. The Merlin will need much higher standards of reliability before it enters service, because of its complexity and the cramped confines from which it will operate.

  11. A Vision for Spaceflight Reliability: NASA's Objectives Based Strategy

    NASA Technical Reports Server (NTRS)

    Groen, Frank; Evans, John; Hall, Tony

    2015-01-01

    In defining the direction for a new Reliability and Maintainability standard, OSMA has extracted the essential objectives that our programs need, to undertake a reliable mission. These objectives have been structured to lead mission planning through construction of an objective hierarchy, which defines the critical approaches for achieving high reliability and maintainability (R M). Creating a hierarchy, as a basis for assurance implementation, is a proven approach; yet, it holds the opportunity to enable new directions, as NASA moves forward in tackling the challenges of space exploration.

  12. Genetic and Rare Diseases Information Center

    MedlinePlus

    ... GARD Information Specialists can provide you with current, reliable, and easy to understand information about rare or ... GARD provides the public with access to current, reliable, and easy-to-understand information about rare or ...

  13. Eye Movement Models of Academic Achievement.

    ERIC Educational Resources Information Center

    Dillon, Ronna F.

    Current pscyhometric assessments, which are based on test score predictors providing information only on products of performance, fail to account for satisfactory amounts of variance in academic achievement or other criterion measures of interest. To corroborate and extend previous work on information processing measures, by examining the…

  14. Project ACHIEVE final report

    SciTech Connect

    1997-06-13

    Project ACHIEVE was a math/science academic enhancement program aimed at first year high school Hispanic American students. Four high schools -- two in El Paso, Texas and two in Bakersfield, California -- participated in this Department of Energy-funded program during the spring and summer of 1996. Over 50 students, many of whom felt they were facing a nightmare future, were given the opportunity to work closely with personal computers and software, sophisticated calculators, and computer-based laboratories -- an experience which their regular academic curriculum did not provide. Math and science projects, exercises, and experiments were completed that emphasized independent and creative applications of scientific and mathematical theories to real world problems. The most important outcome was the exposure Project ACHIEVE provided to students concerning the college and technical-field career possibilities available to them.

  15. Achieving Goal Blood Pressure.

    PubMed

    Laurent, Stéphane

    2015-07-01

    Both monotherapy and combination therapy options are appropriate for antihypertensive therapy according to the 2013 European Society of Hypertension (ESH)/European Society of Cardiology (ESC) guidelines. Most patients require more than one agent to achieve blood pressure (BP) control, and adding a second agent is more effective than doubling the dose of existing therapy. The addition of a third agent may be required to achieve adequate BP reductions in some patients. Single-pill fixed-dose combinations (FDCs) allow multiple-drug regimens to be delivered without any negative impact on patient compliance or persistence with therapy. FDCs also have documented beneficial clinical effects and use of FDCs containing two or three agents is recommended by the 2013 ESH/ESC guidelines. PMID:26002423

  16. Learning reliable manipulation strategies without initial physical models

    NASA Technical Reports Server (NTRS)

    Christiansen, Alan D.; Mason, Matthew T.; Mitchell, Tom M.

    1990-01-01

    A description is given of a robot, possessing limited sensory and effectory capabilities but no initial model of the effects of its actions on the world, that acquires such a model through exploration, practice, and observation. By acquiring an increasingly correct model of its actions, it generates increasingly successful plans to achieve its goals. In an apparently nondeterministic world, achieving reliability requires the identification of reliable actions and a preference for using such actions. Furthermore, by selecting its training actions carefully, the robot can significantly improve its learning rate.

  17. Utility Static Generation Reliability

    Energy Science and Technology Software Center (ESTSC)

    1993-03-05

    PICES (Probabilistic Investigation of Capacity and Energy Shortages) was developed for estimating an electric utility''s expected frequency and duration of capacity deficiencies on a daily on and off-peak basis. In addition to the system loss-of-load probability (LOLP) and loss-of-load expectation (LOLE) indices, PICES calculates the expected frequency and duration of system capacity deficiencies and the probability, expectation, and expected frequency and duration of a range of system reserve margin states. Results are aggregated and printedmore » on a weekly, monthly, or annual basis. The program employs hourly load data and either the two-state (on/off) or a more sophisticated three-state (on/partially on/fully off) generating unit representation. Unit maintenance schedules are determined on a weekly, levelized reserve margin basis. In addition to the 8760-hour annual load record, the user provides the following information for each unit: plant capacity, annual maintenance requirement, two or three-state unit failure and repair rates, and for three-state models, the partial state capacity deficiency. PICES can also supply default failure and repair rate values, based on the Edison Electric Institute''s 1979 Report on Equipment Availability for the Ten-Year Period 1968 Through 1977, for many common plant types. Multi-year analysis can be performed by specifying as input data the annual peak load growth rates and plant addition and retirement schedules for each year in the study.« less

  18. Inter-observer reliability of forceful exertion analysis based on video-recordings.

    PubMed

    Bao, S; Howard, N; Spielholz, P; Silverstein, B

    2010-09-01

    The objectives were to examine inter-observer reliability of job-level forceful exertion analyses and temporal agreement of detailed time study results. Three observers performed the analyses on 12 different jobs. Continuous duration, frequency and % time of lifting, pushing/pulling, power and pinch gripping exertions and estimated level of the exertions were obtained. Intraclass correlation coefficient and variance components were computed. Temporal agreement analyses of raw time study data were performed. The inter-observer reliability was good for most job-level exposure parameters (continuous duration, frequency and % time of forceful exertions), but only fair to moderate for the estimated level of forceful exertions. The finding that the between-observer variability was less than the between-exertion variability confirmed that the forceful exertion analysis method used in the present study can detect job exertion differences.Using three observers to perform detailed time studies on task activities and getting consensus of the majority can increase the between-observer agreement up to 97%. STATEMENT OF RELEVANCE: The results inform researchers that inter-observer reliability for job-level exposure measurement of forceful exertion analysis obtained from detailed time studies is generally good, but the observers' ability in the estimation of forceful exertion level can be poor. It also provides information on the temporal agreement of detailed forceful exertion analysis and guidelines on achieving better agreement for studies where accurate synchronisation of task activities and direct physiological/biomechanical measurements is crucial. PMID:20737338

  19. A win for HROs. Employing high-reliability organization characteristics in EMS.

    PubMed

    Heightman, A J

    2013-06-01

    Was I insubordinate, arrogant or disrespectful? You may feel that I was. But in reality, I was educated to a level that could have been validated and should have been respected by command. I was, in fact, practicing a key aspect of HRO. I was stopping an obvious dangerous condition before it could harm or kill emergency responders. My IC colleague knew it from the facts presented and, in fact, joked with me about my "subtle sarcasm" and moved the perimeter to the recommended half-mile distance. Did I win, or did a proactive HRO win? Actually, HRO won and potentially saved 30 lives. I simply presented the hazards of CFC inhalation. A high-reliability organization must not rely on only one source of data when detailed information on a hazard isn't immediately available, or if it isn't very informative during an emergency decision-making process. Read "EMS & High Reliability Organizing: Achieving safety & reliability in the dynamic, high-risk environment and practice its important principles," pp. 60-63. It's really common sense, not rocket science, and may save you, your crews or others in your community. PMID:24159720

  20. An Overview of the Reliability and Availability Data System (RADS)

    SciTech Connect

    T. E. Wierman; K. J. Kvarfordt; S. A. Eide; D. M. Rasmuson

    2005-09-01

    The Reliability and Availability Data System (RADS) is a database and analysis code, developed by the Idaho National Engineering and Environmental Laboratory (INEEL) for the U.S. Nuclear Regulatory Commission (USNRC). The code is designed to estimate industry and plant-specific reliability and availability parameters for selected components in risk-important systems and initiating events for use in risk-informed applications. The RADS tool contains data and information based on actual operating experience from U.S. commercial nuclear power plants. The data contained in RADS is kept up-to-date by loading the most current quarter's Equipment Performance and Information Exchange (EPIX) data and by yearly lods of initiating event data from licensee event reports (LERS). The reliability parameters estimated by RADS are (1) probability of failure on demand, (2) failure rate during operation (used to calculate failure to run probability) and (3) time trends in reliability parameters.

  1. 18 CFR 39.5 - Reliability Standards.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Reliability Standards... RELIABILITY STANDARDS § 39.5 Reliability Standards. (a) The Electric Reliability Organization shall file each Reliability Standard or modification to a Reliability Standard that it proposes to be made effective...

  2. 18 CFR 39.5 - Reliability Standards.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Reliability Standards... RELIABILITY STANDARDS § 39.5 Reliability Standards. (a) The Electric Reliability Organization shall file each Reliability Standard or modification to a Reliability Standard that it proposes to be made effective...

  3. A reliable multicast for XTP

    NASA Technical Reports Server (NTRS)

    Dempsey, Bert J.; Weaver, Alfred C.

    1990-01-01

    Multicast services needed for current distributed applications on LAN's fall generally into one of three categories: datagram, semi-reliable, and reliable. Transport layer multicast datagrams represent unreliable service in which the transmitting context 'fires and forgets'. XTP executes these semantics when the MULTI and NOERR mode bits are both set. Distributing sensor data and other applications in which application-level error recovery strategies are appropriate benefit from the efficiency in multidestination delivery offered by datagram service. Semi-reliable service refers to multicasting in which the control algorithms of the transport layer--error, flow, and rate control--are used in transferring the multicast distribution to the set of receiving contexts, the multicast group. The multicast defined in XTP provides semi-reliable service. Since, under a semi-reliable service, joining a multicast group means listening on the group address and entails no coordination with other members, a semi-reliable facility can be used for communication between a client and a server group as well as true peer-to-peer group communication. Resource location in a LAN is an important application domain. The term 'semi-reliable' refers to the fact that group membership changes go undetected. No attempt is made to assess the current membership of the group at any time--before, during, or after--the data transfer.

  4. Improve filtration for optimum equipment reliability

    SciTech Connect

    Cervera, S.M.

    1996-01-01

    The introduction 20 years ago of the American Petroleum Institute Standard API-614 as a purchase specification for lubrication, shaft sealing and control oil systems, had a considerable impact and did much to improve system reliability at that time. Today, however, these recommendations regarding filter rating and flushing cleanliness are outdated. Much research in the tribology field correlates clearance size particulate contamination with accelerated component wear, fatigue and performance degradation. Some of these studies demonstrate that by decreasing the population of clearance size particulate in lubrication oils, component life increases exponentially. Knowing the dynamic clearances of a piece of machinery makes it possible, using the ISO 4406 Cleanliness Code, to determine what cleanliness level will minimize contamination-related component wear/fatigue and thus help optimize machinery performance and reliability. Data obtained by the author through random sampling of rotating equipment lube and seal oil systems indicate that the API-614 standard, as it pertains to filtration and flushing, is insufficient to ensure that particulate contamination is maintained to within the levels necessary to achieve optimum equipment reliability and safety, without increasing operating cost. Adopting and practicing the guidelines presented should result in the following benefits: (1) the frequency of bearing, oil pump, mechanical seal, fluid coupling, gearbox and hydraulic control valve failures would be minimized; (2) the mean time between planned maintenance (MTBPM) would be increased. The result will be a substantial increase in safety and cost savings to the operator.

  5. Reliability analysis of interdependent lattices

    NASA Astrophysics Data System (ADS)

    Limiao, Zhang; Daqing, Li; Pengju, Qin; Bowen, Fu; Yinan, Jiang; Zio, Enrico; Rui, Kang

    2016-06-01

    Network reliability analysis has drawn much attention recently due to the risks of catastrophic damage in networked infrastructures. These infrastructures are dependent on each other as a result of various interactions. However, most of the reliability analyses of these interdependent networks do not consider spatial constraints, which are found important for robustness of infrastructures including power grid and transport systems. Here we study the reliability properties of interdependent lattices with different ranges of spatial constraints. Our study shows that interdependent lattices with strong spatial constraints are more resilient than interdependent Erdös-Rényi networks. There exists an intermediate range of spatial constraints, at which the interdependent lattices have minimal resilience.

  6. Identification of components to optimize improvement in system reliability

    SciTech Connect

    Painton, L.; Campbell, J.

    1993-10-01

    The fields of reliability analysis and risk assessment have grown dramatically since the 1970s. There are now bodies of literature and standard practices which cover quantitative aspects of system analysis such as failure rate and repair models, fault and event tree generation, minimal cut sets, classical and Bayesian analysis of reliability, component and system testing techniques, decomposition methods, etc. In spite of the growth in the sophistication of reliability models, however, little has been done to integrate optimization models within a reliability analysis framework. That is, often reliability models focus on characterization of system structure in terms of topology and failure/availability characteristics of components. A number of approaches have been proposed to help identify the components of a system that have the largest influence on overall system reliability. While this may help rank order the components, it does not necessarily help a system design team identify which components they should improve to optimize overall reliability (it may be cheaper and more effective to focus on improving two or three components of smaller importance than one component of larger importance). In this paper, we present an optimization model that identifies the components to be improved to maximize the increase in system MTBF, subject to a fixed budget constraint. A dual formulation of the model is to minimize cost, subject to achieving a certain level of system reliability.

  7. Fault recovery in the reliable multicast protocol

    NASA Technical Reports Server (NTRS)

    Callahan, John R.; Montgomery, Todd L.; Whetten, Brian

    1995-01-01

    The Reliable Multicast Protocol (RMP) provides a unique, group-based model for distributed programs that need to handle reconfiguration events at the application layer. This model, called membership views, provides an abstraction in which events such as site failures, network partitions, and normal join-leave events are viewed as group reformations. RMP provides access to this model through an application programming interface (API) that notifies an application when a group is reformed as the result of a some event. RMP provides applications with reliable delivery of messages using an underlying IP Multicast (12, 5) media to other group members in a distributed environment even in the case of reformations. A distributed application can use various Quality of Service (QoS) levels provided by RMP to tolerate group reformations. This paper explores the implementation details of the mechanisms in RMP that provide distributed applications with membership view information and fault recovery capabilities.

  8. Subsea pipeline isolation systems: Reliability and costs

    SciTech Connect

    Masheder, R.R.

    1996-08-01

    Since the Piper Alpha disaster, more than 80 subsea isolation systems (SSIS) have been installed in subsea gas and oil pipelines in the U.K. continental shelf at an estimated cost in the region of {Brit_pounds}500 million. The reliability and costs of these installations have now been assessed between Dec. 1992 and Oct. 1993. This assessment was based upon comprehensive reliability and cost databases which were established so that the studies could be based upon factual information in order to obtain a current status as required by the sponsoring group. The study consultants report findings have now been consolidated into a report by the UKOOA Pipeline Valve Work Group. Probabilities of failure for different types of valves and systems have been assessed and expenditures broken down and compared. The results of the studies and the conclusions drawn by UKOOA Pipeline Valve Group and the HSE Offshore Safety Division are presented in this paper.

  9. District nebuliser compressor service: reliability and costs.

    PubMed Central

    Dodd, M. E.; Hanley, S. P.; Johnson, S. C.; Webb, A. K.

    1995-01-01

    BACKGROUND--There is little information on the costs of maintaining a district nebuliser compressor service. This retrospective study examines the issue, reliability, and maintenance costs of electrical compressors to assist the prediction of future costs, taking into account recent safety legislation. METHODS--Records of issue, repair, and replacement for the period 1982-91 were reviewed. The current policy of repairing and replacing as necessary, and three other theoretical costings, were considered. RESULTS--The number of compressors being issued is increasing. Repaired compressors are less reliable and frequency of repair is a function of compressor age. The current policy is the most cost effective. CONCLUSIONS--To repair and replace nebuliser compressors as necessary is the most economical policy under the present terms offered by the manufacturers, but changes in safety legislation will affect the provision of such services. PMID:7886657

  10. Achieving Magnet status.

    PubMed

    Ellis, Beckie; Gates, Judy

    2005-01-01

    Magnet has become the gold standard for nursing excellence. It is the symbol of effective and safe patient care. It evaluates components that inspire safe care, including employee satisfaction and retention, professional education, and effective interdisciplinary collaboration. In an organization whose mission focuses on excellent patient care, Banner Thunderbird Medical Center found that pursuing Magnet status was clearly the next step. In this article, we will discuss committee selection, education, team building, planning, and the discovery process that define the Magnet journey. The road to obtaining Magnet status has permitted many opportunities to celebrate our achievements. PMID:16056158

  11. ECLSS Reliability for Long Duration Missions Beyond Lower Earth Orbit

    NASA Technical Reports Server (NTRS)

    Sargusingh, Miriam J.; Nelson, Jason

    2014-01-01

    Reliability has been highlighted by NASA as critical to future human space exploration particularly in the area of environmental controls and life support systems. The Advanced Exploration Systems (AES) projects have been encouraged to pursue higher reliability components and systems as part of technology development plans. However there is no consensus on what is meant by improving on reliability; nor on how to assess reliability within the AES projects. This became apparent when trying to assess reliability as one of several figures of merit for a regenerable water architecture trade study. In the spring of 2013, the AES Water Recovery Project (WRP) hosted a series of events at the NASA Johnson Space Center (JSC) with the intended goal of establishing a common language and understanding of our reliability goals, and equipping the projects with acceptable means of assessing our respective systems. This campaign included an educational series in which experts from across the agency and academia provided information on terminology, tools and techniques associated with evalauating and designing for system reliability. The campaign culminated in a workshop at JSC with members of the ECLSS and AES communities with the goal of developing a consensus on what reliability means to AES and identifying methods for assessing our low to mid-technology readiness level (TRL) technologies for reliability. This paper details the results of the workshop.

  12. ECLSS Reliability for Long Duration Missions Beyond Lower Earth Orbit

    NASA Technical Reports Server (NTRS)

    Sargusingh, Miriam J.; Nelson, Jason

    2014-01-01

    Reliability has been highlighted by NASA as critical to future human space exploration particularly in the area of environmental controls and life support systems. The Advanced Exploration Systems (AES) projects have been encouraged to pursue higher reliability components and systems as part of technology development plans. However, there is no consensus on what is meant by improving on reliability; nor on how to assess reliability within the AES projects. This became apparent when trying to assess reliability as one of several figures of merit for a regenerable water architecture trade study. In the Spring of 2013, the AES Water Recovery Project (WRP) hosted a series of events at the NASA Johnson Space Center (JSC) with the intended goal of establishing a common language and understanding of our reliability goals and equipping the projects with acceptable means of assessing our respective systems. This campaign included an educational series in which experts from across the agency and academia provided information on terminology, tools and techniques associated with evaluating and designing for system reliability. The campaign culminated in a workshop at JSC with members of the ECLSS and AES communities with the goal of developing a consensus on what reliability means to AES and identifying methods for assessing our low to mid-technology readiness level (TRL) technologies for reliability. This paper details the results of the workshop.

  13. High-Reliability Health Care: Getting There from Here

    PubMed Central

    Chassin, Mark R; Loeb, Jerod M

    2013-01-01

    Context Despite serious and widespread efforts to improve the quality of health care, many patients still suffer preventable harm every day. Hospitals find improvement difficult to sustain, and they suffer “project fatigue” because so many problems need attention. No hospitals or health systems have achieved consistent excellence throughout their institutions. High-reliability science is the study of organizations in industries like commercial aviation and nuclear power that operate under hazardous conditions while maintaining safety levels that are far better than those of health care. Adapting and applying the lessons of this science to health care offer the promise of enabling hospitals to reach levels of quality and safety that are comparable to those of the best high-reliability organizations. Methods We combined the Joint Commission's knowledge of health care organizations with knowledge from the published literature and from experts in high-reliability industries and leading safety scholars outside health care. We developed a conceptual and practical framework for assessing hospitals’ readiness for and progress toward high reliability. By iterative testing with hospital leaders, we refined the framework and, for each of its fourteen components, defined stages of maturity through which we believe hospitals must pass to reach high reliability. Findings We discovered that the ways that high-reliability organizations generate and maintain high levels of safety cannot be directly applied to today's hospitals. We defined a series of incremental changes that hospitals should undertake to progress toward high reliability. These changes involve the leadership's commitment to achieving zero patient harm, a fully functional culture of safety throughout the organization, and the widespread deployment of highly effective process improvement tools. Conclusions Hospitals can make substantial progress toward high reliability by undertaking several specific

  14. Mass and Reliability System (MaRS)

    NASA Technical Reports Server (NTRS)

    Barnes, Sarah

    2016-01-01

    The Safety and Mission Assurance (S&MA) Directorate is responsible for mitigating risk, providing system safety, and lowering risk for space programs from ground to space. The S&MA is divided into 4 divisions: The Space Exploration Division (NC), the International Space Station Division (NE), the Safety & Test Operations Division (NS), and the Quality and Flight Equipment Division (NT). The interns, myself and Arun Aruljothi, will be working with the Risk & Reliability Analysis Branch under the NC Division's. The mission of this division is to identify, characterize, diminish, and communicate risk by implementing an efficient and effective assurance model. The team utilizes Reliability and Maintainability (R&M) and Probabilistic Risk Assessment (PRA) to ensure decisions concerning risks are informed, vehicles are safe and reliable, and program/project requirements are realistic and realized. This project pertains to the Orion mission, so it is geared toward a long duration Human Space Flight Program(s). For space missions, payload is a critical concept; balancing what hardware can be replaced by components verse by Orbital Replacement Units (ORU) or subassemblies is key. For this effort a database was created that combines mass and reliability data, called Mass and Reliability System or MaRS. The U.S. International Space Station (ISS) components are used as reference parts in the MaRS database. Using ISS components as a platform is beneficial because of the historical context and the environment similarities to a space flight mission. MaRS uses a combination of systems: International Space Station PART for failure data, Vehicle Master Database (VMDB) for ORU & components, Maintenance & Analysis Data Set (MADS) for operation hours and other pertinent data, & Hardware History Retrieval System (HHRS) for unit weights. MaRS is populated using a Visual Basic Application. Once populated, the excel spreadsheet is comprised of information on ISS components including

  15. An experiment in software reliability

    NASA Technical Reports Server (NTRS)

    Dunham, J. R.; Pierce, J. L.

    1986-01-01

    The results of a software reliability experiment conducted in a controlled laboratory setting are reported. The experiment was undertaken to gather data on software failures and is one in a series of experiments being pursued by the Fault Tolerant Systems Branch of NASA Langley Research Center to find a means of credibly performing reliability evaluations of flight control software. The experiment tests a small sample of implementations of radar tracking software having ultra-reliability requirements and uses n-version programming for error detection, and repetitive run modeling for failure and fault rate estimation. The experiment results agree with those of Nagel and Skrivan in that the program error rates suggest an approximate log-linear pattern and the individual faults occurred with significantly different error rates. Additional analysis of the experimental data raises new questions concerning the phenomenon of interacting faults. This phenomenon may provide one explanation for software reliability decay.

  16. Failure Analysis for Improved Reliability

    NASA Technical Reports Server (NTRS)

    Sood, Bhanu

    2016-01-01

    Outline: Section 1 - What is reliability and root cause? Section 2 - Overview of failure mechanisms. Section 3 - Failure analysis techniques (1. Non destructive analysis techniques, 2. Destructive Analysis, 3. Materials Characterization). Section 4 - Summary and Closure

  17. GaAs Reliability Database

    NASA Technical Reports Server (NTRS)

    Sacco, T.; Gonzalez, S.; Kayali, S.

    1993-01-01

    The database consists of two main sections, the data references and the device reliability records. The reference section contains 8 fields: reference number, date of publication, authors, article title, publisher, volume, and page numbers.

  18. Achievement Evaluation: A Fundamental Difference and its Motivational Consequences.

    ERIC Educational Resources Information Center

    Rheinberg, Falko

    1983-01-01

    Informal but frequent teacher evaluations of students' academic achievement are not standardized by official prescriptions dictating which reference system is to be used. Three reference norms used when evaluating achievement are: social, criterion-oriented, and individual reference norms. (PN)

  19. Photovoltaics Performance and Reliability Workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    This document consists of papers and viewgraphs compiled from the proceedings of a workshop held in September 1992. This workshop was the fifth in a series sponsored by NREL/DOE under the general subject areas of photovoltaic module testing and reliability. PV manufacturers, DOE laboratories, electric utilities, and others exchanged technical knowledge and field experience. The topics of cell and module characterization, module and system performance, materials and module durability/reliability research, solar radiation, and applications are discussed.

  20. Accelerator Availability and Reliability Issues

    SciTech Connect

    Steve Suhring

    2003-05-01

    Maintaining reliable machine operations for existing machines as well as planning for future machines' operability present significant challenges to those responsible for system performance and improvement. Changes to machine requirements and beam specifications often reduce overall machine availability in an effort to meet user needs. Accelerator reliability issues from around the world will be presented, followed by a discussion of the major factors influencing machine availability.