On-clip high frequency reliability and failure test structures
Snyder, Eric S.; Campbell, David V.
1997-01-01
Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer.
On-clip high frequency reliability and failure test structures
Snyder, E.S.; Campbell, D.V.
1997-04-29
Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer. 22 figs.
Review of Reliability-Based Design Optimization Approach and Its Integration with Bayesian Method
NASA Astrophysics Data System (ADS)
Zhang, Xiangnan
2018-03-01
A lot of uncertain factors lie in practical engineering, such as external load environment, material property, geometrical shape, initial condition, boundary condition, etc. Reliability method measures the structural safety condition and determine the optimal design parameter combination based on the probabilistic theory. Reliability-based design optimization (RBDO) is the most commonly used approach to minimize the structural cost or other performance under uncertainty variables which combines the reliability theory and optimization. However, it cannot handle the various incomplete information. The Bayesian approach is utilized to incorporate this kind of incomplete information in its uncertainty quantification. In this paper, the RBDO approach and its integration with Bayesian method are introduced.
Design of high reliability organizations in health care.
Carroll, J S; Rudolph, J W
2006-12-01
To improve safety performance, many healthcare organizations have sought to emulate high reliability organizations from industries such as nuclear power, chemical processing, and military operations. We outline high reliability design principles for healthcare organizations including both the formal structures and the informal practices that complement those structures. A stage model of organizational structures and practices, moving from local autonomy to formal controls to open inquiry to deep self-understanding, is used to illustrate typical challenges and design possibilities at each stage. We suggest how organizations can use the concepts and examples presented to increase their capacity to self-design for safety and reliability.
Time-Varying, Multi-Scale Adaptive System Reliability Analysis of Lifeline Infrastructure Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gearhart, Jared Lee; Kurtz, Nolan Scot
2014-09-01
The majority of current societal and economic needs world-wide are met by the existing networked, civil infrastructure. Because the cost of managing such infrastructure is high and increases with time, risk-informed decision making is essential for those with management responsibilities for these systems. To address such concerns, a methodology that accounts for new information, deterioration, component models, component importance, group importance, network reliability, hierarchical structure organization, and efficiency concerns has been developed. This methodology analyzes the use of new information through the lens of adaptive Importance Sampling for structural reliability problems. Deterioration, multi-scale bridge models, and time-variant component importance aremore » investigated for a specific network. Furthermore, both bridge and pipeline networks are studied for group and component importance, as well as for hierarchical structures in the context of specific networks. Efficiency is the primary driver throughout this study. With this risk-informed approach, those responsible for management can address deteriorating infrastructure networks in an organized manner.« less
NASA Astrophysics Data System (ADS)
Kuvich, Gary
2004-08-01
Vision is only a part of a system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, which is an interpretation of visual information in terms of these knowledge models. These mechanisms provide a reliable recognition if the object is occluded or cannot be recognized as a whole. It is hard to split the entire system apart, and reliable solutions to the target recognition problems are possible only within the solution of a more generic Image Understanding Problem. Brain reduces informational and computational complexities, using implicit symbolic coding of features, hierarchical compression, and selective processing of visual information. Biologically inspired Network-Symbolic representation, where both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, is the most feasible for such models. It converts visual information into relational Network-Symbolic structures, avoiding artificial precise computations of 3-dimensional models. Network-Symbolic Transformations derive abstract structures, which allows for invariant recognition of an object as exemplar of a class. Active vision helps creating consistent models. Attention, separation of figure from ground and perceptual grouping are special kinds of network-symbolic transformations. Such Image/Video Understanding Systems will be reliably recognizing targets.
ERIC Educational Resources Information Center
Reutzel, D. Ray; Jones, Cindy D.; Clark, Sarah K.; Kumar, Tamara
2016-01-01
There has been no research reported about if or how well primary grade teachers can identify information text structures in children's authentic informational texts. The ability to do so accurately and reliably is a prerequisite for teachers to be able to teach students how to recognize and use text structures to assist them in comprehending…
Design of high reliability organizations in health care
Carroll, J S; Rudolph, J W
2006-01-01
To improve safety performance, many healthcare organizations have sought to emulate high reliability organizations from industries such as nuclear power, chemical processing, and military operations. We outline high reliability design principles for healthcare organizations including both the formal structures and the informal practices that complement those structures. A stage model of organizational structures and practices, moving from local autonomy to formal controls to open inquiry to deep self‐understanding, is used to illustrate typical challenges and design possibilities at each stage. We suggest how organizations can use the concepts and examples presented to increase their capacity to self‐design for safety and reliability. PMID:17142607
Report: Studies Addressing EPA’s Organizational Structure
Report #2006-P-00029, August 16, 2006. The 13 studies, articles, publications, and reports we reviewed identified issues with cross-media management, regional offices, reliable information, and reliable science.
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…
Williams, Janet B W; Kobak, Kenneth A
2008-01-01
The Montgomery-Asberg Depression Rating Scale (MADRS) is often used in clinical trials to select patients and to assess treatment efficacy. The scale was originally published without suggested questions for clinicians to use in gathering the information necessary to rate the items. Structured and semi-structured interview guides have been found to improve reliability with other scales. To describe the development and test-retest reliability of a structured interview guide for the MADRS (SIGMA). A total of 162 test-retest interviews were conducted by 81 rater pairs. Each patient was interviewed twice, once by each rater conducting an independent interview. The intraclass correlation for total score between raters using the SIGMA was r=0.93, P<0.0001. All ten items had good to excellent interrater reliability. Use of the SIGMA can result in high reliability of MADRS scores in evaluating patients with depression.
A new statistical framework to assess structural alignment quality using information compression
Collier, James H.; Allison, Lloyd; Lesk, Arthur M.; Garcia de la Banda, Maria; Konagurthu, Arun S.
2014-01-01
Motivation: Progress in protein biology depends on the reliability of results from a handful of computational techniques, structural alignments being one. Recent reviews have highlighted substantial inconsistencies and differences between alignment results generated by the ever-growing stock of structural alignment programs. The lack of consensus on how the quality of structural alignments must be assessed has been identified as the main cause for the observed differences. Current methods assess structural alignment quality by constructing a scoring function that attempts to balance conflicting criteria, mainly alignment coverage and fidelity of structures under superposition. This traditional approach to measuring alignment quality, the subject of considerable literature, has failed to solve the problem. Further development along the same lines is unlikely to rectify the current deficiencies in the field. Results: This paper proposes a new statistical framework to assess structural alignment quality and significance based on lossless information compression. This is a radical departure from the traditional approach of formulating scoring functions. It links the structural alignment problem to the general class of statistical inductive inference problems, solved using the information-theoretic criterion of minimum message length. Based on this, we developed an efficient and reliable measure of structural alignment quality, I-value. The performance of I-value is demonstrated in comparison with a number of popular scoring functions, on a large collection of competing alignments. Our analysis shows that I-value provides a rigorous and reliable quantification of structural alignment quality, addressing a major gap in the field. Availability: http://lcb.infotech.monash.edu.au/I-value Contact: arun.konagurthu@monash.edu Supplementary information: Online supplementary data are available at http://lcb.infotech.monash.edu.au/I-value/suppl.html PMID:25161241
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…
NASA Technical Reports Server (NTRS)
Thomas, J. M.; Hanagud, S.
1974-01-01
The design criteria and test options for aerospace structural reliability were investigated. A decision methodology was developed for selecting a combination of structural tests and structural design factors. The decision method involves the use of Bayesian statistics and statistical decision theory. Procedures are discussed for obtaining and updating data-based probabilistic strength distributions for aerospace structures when test information is available and for obtaining subjective distributions when data are not available. The techniques used in developing the distributions are explained.
The relationship between cost estimates reliability and BIM adoption: SEM analysis
NASA Astrophysics Data System (ADS)
Ismail, N. A. A.; Idris, N. H.; Ramli, H.; Rooshdi, R. R. Raja Muhammad; Sahamir, S. R.
2018-02-01
This paper presents the usage of Structural Equation Modelling (SEM) approach in analysing the effects of Building Information Modelling (BIM) technology adoption in improving the reliability of cost estimates. Based on the questionnaire survey results, SEM analysis using SPSS-AMOS application examined the relationships between BIM-improved information and cost estimates reliability factors, leading to BIM technology adoption. Six hypotheses were established prior to SEM analysis employing two types of SEM models, namely the Confirmatory Factor Analysis (CFA) model and full structural model. The SEM models were then validated through the assessment on their uni-dimensionality, validity, reliability, and fitness index, in line with the hypotheses tested. The final SEM model fit measures are: P-value=0.000, RMSEA=0.079<0.08, GFI=0.824, CFI=0.962>0.90, TLI=0.956>0.90, NFI=0.935>0.90 and ChiSq/df=2.259; indicating that the overall index values achieved the required level of model fitness. The model supports all the hypotheses evaluated, confirming that all relationship exists amongst the constructs are positive and significant. Ultimately, the analysis verified that most of the respondents foresee better understanding of project input information through BIM visualization, its reliable database and coordinated data, in developing more reliable cost estimates. They also perceive to accelerate their cost estimating task through BIM adoption.
Structural Test Laboratory | Water Power | NREL
Structural Test Laboratory Structural Test Laboratory NREL engineers design and configure structural components can validate models, demonstrate system reliability, inform design margins, and assess , including mass and center of gravity, to ensure compliance with design goals Dynamic Characterization Use
An integrated approach to system design, reliability, and diagnosis
NASA Technical Reports Server (NTRS)
Patterson-Hine, F. A.; Iverson, David L.
1990-01-01
The requirement for ultradependability of computer systems in future avionics and space applications necessitates a top-down, integrated systems engineering approach for design, implementation, testing, and operation. The functional analyses of hardware and software systems must be combined by models that are flexible enough to represent their interactions and behavior. The information contained in these models must be accessible throughout all phases of the system life cycle in order to maintain consistency and accuracy in design and operational decisions. One approach being taken by researchers at Ames Research Center is the creation of an object-oriented environment that integrates information about system components required in the reliability evaluation with behavioral information useful for diagnostic algorithms. Procedures have been developed at Ames that perform reliability evaluations during design and failure diagnoses during system operation. These procedures utilize information from a central source, structured as object-oriented fault trees. Fault trees were selected because they are a flexible model widely used in aerospace applications and because they give a concise, structured representation of system behavior. The utility of this integrated environment for aerospace applications in light of our experiences during its development and use is described. The techniques for reliability evaluation and failure diagnosis are discussed, and current extensions of the environment and areas requiring further development are summarized.
An integrated approach to system design, reliability, and diagnosis
NASA Astrophysics Data System (ADS)
Patterson-Hine, F. A.; Iverson, David L.
1990-12-01
The requirement for ultradependability of computer systems in future avionics and space applications necessitates a top-down, integrated systems engineering approach for design, implementation, testing, and operation. The functional analyses of hardware and software systems must be combined by models that are flexible enough to represent their interactions and behavior. The information contained in these models must be accessible throughout all phases of the system life cycle in order to maintain consistency and accuracy in design and operational decisions. One approach being taken by researchers at Ames Research Center is the creation of an object-oriented environment that integrates information about system components required in the reliability evaluation with behavioral information useful for diagnostic algorithms. Procedures have been developed at Ames that perform reliability evaluations during design and failure diagnoses during system operation. These procedures utilize information from a central source, structured as object-oriented fault trees. Fault trees were selected because they are a flexible model widely used in aerospace applications and because they give a concise, structured representation of system behavior. The utility of this integrated environment for aerospace applications in light of our experiences during its development and use is described. The techniques for reliability evaluation and failure diagnosis are discussed, and current extensions of the environment and areas requiring further development are summarized.
[Evaluation of an educational website on First Aid].
Mori, Satomi; Whitaker, Iveth Yamaguchi; Marin, Heimar de Fátima
2013-08-01
The aim of this study was to evaluate the structure, quality of information and usability of a website on First Aid. The evaluation was performed by information technology (IT) and health care professionals and by students, using specific and validated instruments. The kappa method was used to evaluate the agreement of the answers, and Cronbach's α coefficient was used to assess the reliability of the instrument. There was no agreement (0.047) among the answers obtained from the IT professionals, indicating that the structure of the website must be reviewed. There was also no agreement in the evaluation by the health care professionals (-0.062); however, the overall positive scores suggest that the quality of the information of the website is adequate. The assessment of reliability of the instrument to evaluate the navigability rendered a value of α=0.974. Although improvement of the website structure is recommended, the quality of the information is good, and its use has contributed to the apprenticeship of students.
Reliability of the Suicide Opinion Questionnaire.
ERIC Educational Resources Information Center
Rogers, James R.; DeShon, Richard P.
The lack of systematic psychometric information on the Suicide Opinion Questionnaire (SOQ) was addressed by investigating the factor structure and reliability of the eight-factor clinical scale model (mental illness, cry for help, right to die, religion, impulsivity, normality, aggression, and moral evil), developed for interpreting responses to…
[Osteosarcoma: reliability and quality of the information in the internet].
Schippinger, Michael; Ruckenstuhl, Paul; Friesenbichler, Jörg; Leithner, Andreas
2014-09-01
The World Wide Web has grown during the last years to a considerable source of medical information for experts as well as for laymen and patients. The quality of this information is subjected to some limitation linked with the structure of the Internet and the management of Internet pages. The cross- sectional study presented evaluates and compares quality and reliability of information with respect of osteosarcoma in the most common German-language Internet pages for medical information. As both, one of the most common primary malignant bone tumors and its peak of incidence at the age of childhood and youth, osteosarcoma is considered of significant importance in orthopedic oncology.
Distributed cooperative control of AC microgrids
NASA Astrophysics Data System (ADS)
Bidram, Ali
In this dissertation, the comprehensive secondary control of electric power microgrids is of concern. Microgrid technical challenges are mainly realized through the hierarchical control structure, including primary, secondary, and tertiary control levels. Primary control level is locally implemented at each distributed generator (DG), while the secondary and tertiary control levels are conventionally implemented through a centralized control structure. The centralized structure requires a central controller which increases the reliability concerns by posing the single point of failure. In this dissertation, the distributed control structure using the distributed cooperative control of multi-agent systems is exploited to increase the secondary control reliability. The secondary control objectives are microgrid voltage and frequency, and distributed generators (DGs) active and reactive powers. Fully distributed control protocols are implemented through distributed communication networks. In the distributed control structure, each DG only requires its own information and the information of its neighbors on the communication network. The distributed structure obviates the requirements for a central controller and complex communication network which, in turn, improves the system reliability. Since the DG dynamics are nonlinear and non-identical, input-output feedback linearization is used to transform the nonlinear dynamics of DGs to linear dynamics. Proposed control frameworks cover the control of microgrids containing inverter-based DGs. Typical microgrid test systems are used to verify the effectiveness of the proposed control protocols.
Space flight risk data collection and analysis project: Risk and reliability database
NASA Technical Reports Server (NTRS)
1994-01-01
The focus of the NASA 'Space Flight Risk Data Collection and Analysis' project was to acquire and evaluate space flight data with the express purpose of establishing a database containing measurements of specific risk assessment - reliability - availability - maintainability - supportability (RRAMS) parameters. The developed comprehensive RRAMS database will support the performance of future NASA and aerospace industry risk and reliability studies. One of the primary goals has been to acquire unprocessed information relating to the reliability and availability of launch vehicles and the subsystems and components thereof from the 45th Space Wing (formerly Eastern Space and Missile Command -ESMC) at Patrick Air Force Base. After evaluating and analyzing this information, it was encoded in terms of parameters pertinent to ascertaining reliability and availability statistics, and then assembled into an appropriate database structure.
How reliable are clinical systems in the UK NHS? A study of seven NHS organisations
Franklin, Bryony Dean; Moorthy, Krishna; Cooke, Matthew W; Vincent, Charles
2012-01-01
Background It is well known that many healthcare systems have poor reliability; however, the size and pervasiveness of this problem and its impact has not been systematically established in the UK. The authors studied four clinical systems: clinical information in surgical outpatient clinics, prescribing for hospital inpatients, equipment in theatres, and insertion of peripheral intravenous lines. The aim was to describe the nature, extent and variation in reliability of these four systems in a sample of UK hospitals, and to explore the reasons for poor reliability. Methods Seven UK hospital organisations were involved; each system was studied in three of these. The authors took delivery of the systems' intended outputs to be a proxy for the reliability of the system as a whole. For example, for clinical information, 100% reliability was defined as all patients having an agreed list of clinical information available when needed during their appointment. Systems factors were explored using semi-structured interviews with key informants. Common themes across the systems were identified. Results Overall reliability was found to be between 81% and 87% for the systems studied, with significant variation between organisations for some systems: clinical information in outpatient clinics ranged from 73% to 96%; prescribing for hospital inpatients 82–88%; equipment availability in theatres 63–88%; and availability of equipment for insertion of peripheral intravenous lines 80–88%. One in five reliability failures were associated with perceived threats to patient safety. Common factors causing poor reliability included lack of feedback, lack of standardisation, and issues such as access to information out of working hours. Conclusions Reported reliability was low for the four systems studied, with some common factors behind each. However, this hides significant variation between organisations for some processes, suggesting that some organisations have managed to create more reliable systems. Standardisation of processes would be expected to have significant benefit. PMID:22495099
Limits on reliable information flows through stochastic populations.
Boczkowski, Lucas; Natale, Emanuele; Feinerman, Ofer; Korman, Amos
2018-06-06
Biological systems can share and collectively process information to yield emergent effects, despite inherent noise in communication. While man-made systems often employ intricate structural solutions to overcome noise, the structure of many biological systems is more amorphous. It is not well understood how communication noise may affect the computational repertoire of such groups. To approach this question we consider the basic collective task of rumor spreading, in which information from few knowledgeable sources must reliably flow into the rest of the population. We study the effect of communication noise on the ability of groups that lack stable structures to efficiently solve this task. We present an impossibility result which strongly restricts reliable rumor spreading in such groups. Namely, we prove that, in the presence of even moderate levels of noise that affect all facets of the communication, no scheme can significantly outperform the trivial one in which agents have to wait until directly interacting with the sources-a process which requires linear time in the population size. Our results imply that in order to achieve efficient rumor spread a system must exhibit either some degree of structural stability or, alternatively, some facet of the communication which is immune to noise. We then corroborate this claim by providing new analyses of experimental data regarding recruitment in Cataglyphis niger desert ants. Finally, in light of our theoretical results, we discuss strategies to overcome noise in other biological systems.
Reliability Technology to Achieve Insertion of Advanced Packaging (RELTECH) program
NASA Astrophysics Data System (ADS)
Fayette, Daniel F.; Speicher, Patricia; Stoklosa, Mark J.; Evans, Jillian V.; Evans, John W.; Gentile, Mike; Pagel, Chuck A.; Hakim, Edward
1993-08-01
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.
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.
On imputing function to structure from the behavioural effects of brain lesions.
Young, M P; Hilgetag, C C; Scannell, J W
2000-01-29
What is the link, if any, between the patterns of connections in the brain and the behavioural effects of localized brain lesions? We explored this question in four related ways. First, we investigated the distribution of activity decrements that followed simulated damage to elements of the thalamocortical network, using integrative mechanisms that have recently been used to successfully relate connection data to information on the spread of activation, and to account simultaneously for a variety of lesion effects. Second, we examined the consequences of the patterns of decrement seen in the simulation for each type of inference that has been employed to impute function to structure on the basis of the effects of brain lesions. Every variety of conventional inference, including double dissociation, readily misattributed function to structure. Third, we tried to derive a more reliable framework of inference for imputing function to structure, by clarifying concepts of function, and exploring a more formal framework, in which knowledge of connectivity is necessary but insufficient, based on concepts capable of mathematical specification. Fourth, we applied this framework to inferences about function relating to a simple network that reproduces intact, lesioned and paradoxically restored orientating behaviour. Lesion effects could be used to recover detailed and reliable information on which structures contributed to particular functions in this simple network. Finally, we explored how the effects of brain lesions and this formal approach could be used in conjunction with information from multiple neuroscience methodologies to develop a practical and reliable approach to inferring the functional roles of brain structures.
Zhang, Dengke; Pang, Yanxia; Cai, Weixiong; Fazio, Rachel L; Ge, Jianrong; Su, Qiaorong; Xu, Shuiqin; Pan, Yinan; Chen, Sanmei; Zhang, Hongwei
2016-08-01
Impairment of theory of mind (ToM) is a common phenomenon following traumatic brain injury (TBI) that has clear effects on patients' social functioning. A growing body of research has focused on this area, and several methods have been developed to assess ToM deficiency. Although an informant assessment scale would be useful for examining individuals with TBI, very few studies have adopted this approach. The purpose of the present study was to develop an informant assessment scale of ToM for adults with traumatic brain injury (IASToM-aTBI) and to test its reliability and validity with 196 adults with TBI and 80 normal adults. A 44-item scale was developed following a literature review, interviews with patient informants, consultations with experts, item analysis, and exploratory factor analysis (EFA). The following three common factors were extracted: social interaction, understanding of beliefs, and understanding of emotions. The psychometric analyses indicate that the scale has good internal consistency reliability, split-half reliability, test-retest reliability, inter-rater reliability, structural validity, discriminate validity and criterion validity. These results provide preliminary evidence that supports the reliability and validity of the IASToM-aTBI as a ToM assessment tool for adults with TBI.
Stellefson, Michael; Paige, Samantha R; Tennant, Bethany; Alber, Julia M; Chaney, Beth H; Chaney, Don; Grossman, Suzanne
2017-10-26
Only a handful of studies have examined reliability and validity evidence of scores produced by the 8-item eHealth literacy Scale (eHEALS) among older adults. Older adults are generally more comfortable responding to survey items when asked by a real person rather than by completing self-administered paper-and-pencil or online questionnaires. However, no studies have explored the psychometrics of this scale when administered to older adults over the telephone. The objective of our study was to examine the reliability and internal structure of eHEALS data collected from older adults aged 50 years or older responding to items over the telephone. Respondents (N=283) completed eHEALS as part of a cross-sectional landline telephone survey. Exploratory structural equation modeling (E-SEM) analyses examined model fit of eHEALS scores with 1-, 2-, and 3-factor structures. Subsequent analyses based on the partial credit model explored the internal structure of eHEALS data. Compared with 1- and 2-factor models, the 3-factor eHEALS structure showed the best global E-SEM model fit indices (root mean square error of approximation=.07; comparative fit index=1.0; Tucker-Lewis index=1.0). Nonetheless, the 3 factors were highly correlated (r range .36 to .65). Item analyses revealed that eHEALS items 2 through 5 were overfit to a minor degree (mean square infit/outfit values <1.0; t statistics less than -2.0), but the internal structure of Likert scale response options functioned as expected. Overfitting eHEALS items (2-5) displayed a similar degree of information for respondents at similar points on the latent continuum. Test information curves suggested that eHEALS may capture more information about older adults at the higher end of the latent continuum (ie, those with high eHealth literacy) than at the lower end of the continuum (ie, those with low eHealth literacy). Item reliability (value=.92) and item separation (value=11.31) estimates indicated that eHEALS responses were reliable and stable. Results support administering eHEALS over the telephone when surveying older adults regarding their use of the Internet for health information. eHEALS scores best captured 3 factors (or subscales) to measure eHealth literacy in older adults; however, statistically significant correlations between these 3 factors suggest an overarching unidimensional structure with 3 underlying dimensions. As older adults continue to use the Internet more frequently to find and evaluate health information, it will be important to consider modifying the original eHEALS to adequately measure societal shifts in online health information seeking among aging populations. ©Michael Stellefson, Samantha R Paige, Bethany Tennant, Julia M Alber, Beth H Chaney, Don Chaney, Suzanne Grossman. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 26.10.2017.
Information Superhighway: An Overview of Technology Challenges. Report to the Congress.
ERIC Educational Resources Information Center
General Accounting Office, Washington, DC.
This report focuses on the pivotal technical issues associated with the National Information Infrastructure program, security and privacy, interoperability, and reliability, and presents the General Accounting Office's findings on these challenges. It is reported that while the structures and services to be offered by the information superhighway…
Cooley, Richard L.
1982-01-01
Prior information on the parameters of a groundwater flow model can be used to improve parameter estimates obtained from nonlinear regression solution of a modeling problem. Two scales of prior information can be available: (1) prior information having known reliability (that is, bias and random error structure) and (2) prior information consisting of best available estimates of unknown reliability. A regression method that incorporates the second scale of prior information assumes the prior information to be fixed for any particular analysis to produce improved, although biased, parameter estimates. Approximate optimization of two auxiliary parameters of the formulation is used to help minimize the bias, which is almost always much smaller than that resulting from standard ridge regression. It is shown that if both scales of prior information are available, then a combined regression analysis may be made.
A multistage motion vector processing method for motion-compensated frame interpolation.
Huang, Ai- Mei; Nguyen, Truong Q
2008-05-01
In this paper, a novel, low-complexity motion vector processing algorithm at the decoder is proposed for motion-compensated frame interpolation or frame rate up-conversion. We address the problems of having broken edges and deformed structures in an interpolated frame by hierarchically refining motion vectors on different block sizes. Our method explicitly considers the reliability of each received motion vector and has the capability of preserving the structure information. This is achieved by analyzing the distribution of residual energies and effectively merging blocks that have unreliable motion vectors. The motion vector reliability information is also used as a prior knowledge in motion vector refinement using a constrained vector median filter to avoid choosing identical unreliable one. We also propose using chrominance information in our method. Experimental results show that the proposed scheme has better visual quality and is also robust, even in video sequences with complex scenes and fast motion.
Nuclear surface diffuseness revealed in nucleon-nucleus diffraction
NASA Astrophysics Data System (ADS)
Hatakeyama, S.; Horiuchi, W.; Kohama, A.
2018-05-01
The nuclear surface provides useful information on nuclear radius, nuclear structure, as well as properties of nuclear matter. We discuss the relationship between the nuclear surface diffuseness and elastic scattering differential cross section at the first diffraction peak of high-energy nucleon-nucleus scattering as an efficient tool in order to extract the nuclear surface information from limited experimental data involving short-lived unstable nuclei. The high-energy reaction is described by a reliable microscopic reaction theory, the Glauber model. Extending the idea of the black sphere model, we find one-to-one correspondence between the nuclear bulk structure information and proton-nucleus elastic scattering diffraction peak. This implies that we can extract both the nuclear radius and diffuseness simultaneously, using the position of the first diffraction peak and its magnitude of the elastic scattering differential cross section. We confirm the reliability of this approach by using realistic density distributions obtained by a mean-field model.
Risk-Informed Mean Recurrence Intervals for Updated Wind Maps in ASCE 7-16.
McAllister, Therese P; Wang, Naiyu; Ellingwood, Bruce R
2018-05-01
ASCE 7 is moving toward adopting load requirements that are consistent with risk-informed design goals characteristic of performance-based engineering (PBE). ASCE 7-10 provided wind maps that correspond to return periods of 300, 700, and 1,700 years for Risk Categories I, II, and combined III/IV, respectively. The risk targets for Risk Categories III and IV buildings and other structures (designated as essential facilities) are different in PBE. The reliability analyses reported in this paper were conducted using updated wind load data to (1) confirm that the return periods already in ASCE 7-10 were also appropriate for risk-informed PBE, and (2) to determine a new risk-based return period for Risk Category IV. The use of data for wind directionality factor, K d , which has become available from recent wind tunnel tests, revealed that reliabilities associated with wind load combinations for Risk Category II structures are, in fact, consistent with the reliabilities associated with the ASCE 7 gravity load combinations. This paper shows that the new wind maps in ASCE 7-16, which are based on return periods of 300, 700, 1,700, and 3,000 years for Risk Categories I, II, III, and IV, respectively), achieve the reliability targets in Section 1.3.1.3 of ASCE 7-16 for nonhurricane wind loads.
Reading PDB: perception of molecules from 3D atomic coordinates.
Urbaczek, Sascha; Kolodzik, Adrian; Groth, Inken; Heuser, Stefan; Rarey, Matthias
2013-01-28
The analysis of small molecule crystal structures is a common way to gather valuable information for drug development. The necessary structural data is usually provided in specific file formats containing only element identities and three-dimensional atomic coordinates as reliable chemical information. Consequently, the automated perception of molecular structures from atomic coordinates has become a standard task in cheminformatics. The molecules generated by such methods must be both chemically valid and reasonable to provide a reliable basis for subsequent calculations. This can be a difficult task since the provided coordinates may deviate from ideal molecular geometries due to experimental uncertainties or low resolution. Additionally, the quality of the input data often differs significantly thus making it difficult to distinguish between actual structural features and mere geometric distortions. We present a method for the generation of molecular structures from atomic coordinates based on the recently published NAOMI model. By making use of this consistent chemical description, our method is able to generate reliable results even with input data of low quality. Molecules from 363 Protein Data Bank (PDB) entries could be perceived with a success rate of 98%, a result which could not be achieved with previously described methods. The robustness of our approach has been assessed by processing all small molecules from the PDB and comparing them to reference structures. The complete data set can be processed in less than 3 min, thus showing that our approach is suitable for large scale applications.
Hendrie, H. C.; Lane, K. A.; Ogunniyi, A.; Baiyewu, O.; Gureje, O.; Evans, R.; Smith-Gamble, V.; Pettaway, M.; Unverzagt, F. W.; Gao, S.; Hall, K. S.
2010-01-01
Background Assessing function is a crucial element in the diagnosis of dementia. This information is usually obtained from key informants. However, reliable informants are not always available. Methods A 10-item semi-structured home interview (the CHIF, or Clinician Home-based Interview to assess Function) to assess function primarily by measuring instrumental activities of daily living directly was developed and tested for inter-rater reliability and validity as part of the Indianapolis–Ibadan dementia project. The primary validity measurements were correlations between scores on the CHIF and independently gathered scores on the Blessed Dementia Scale (from informants) and the Mini-mental State Examination (MMSE). Sensitivities and specificities of scores on the CHIF and receiver operator characteristic (ROC) curves were constructed with dementia as the dependent variable. Results Inter-rater reliability for the CHIF was high (Pearson’s correlation coefficient 0.99 in Indianapolis and 0.87 in Ibadan). Internal consistency, in both samples, was good (Cronbach’s α 0.95 in Indianapolis and 0.83 in Ibadan). Scores on the CHIF correlated well with the Blessed Dementia scores at both sites (−0.71, p < 0.0001 for Indianapolis and −0.56, p < 0.0001 for Ibadan) and with the MMSE (0.75, p < 0.0001 for Indianapolis and 0.44, p < 0.0001 for Ibadan). For all items at both sites, the subjects without dementia performed significantly better than those with dementia. The area under the ROC curve for dementia diagnosis was 0.965 for Indianapolis and 0.925 for Ibadan. Conclusion The CHIF is a useful instrument to assess function directly in elderly participants in international studies, particularly in the absence of reliable informants. PMID:16640794
Dreessen, L; Arntz, A
1998-01-01
The short-interval test-retest interrater reliability of the Structured Clinical Interview for DSM-III-R personality disorders (SCID-II) was studied in a psychotherapy outpatient group whose main complaint was mostly an Axis I anxiety disorder. Using a test-retest approach to assess interrater reliability, three sources of variance were taken into account (rater variance in the elicitation and interpretation of information and patient variance across interviews). Base rate requirements were established before calculating reliability coefficients. On the whole, interrater agreement on the SCID-II was found to be satisfactory, except for the histrionic personality traits. This is the first study that has estimated short-interval test-retest interrater reliability of the SCID-II in outpatients, and also the first that has studied single SCID-II traits and dimensional diagnoses. The results found support the use of the SCID-II as a diagnostic instrument for clinical and research purposes.
Bridge reliability assessment based on the PDF of long-term monitored extreme strains
NASA Astrophysics Data System (ADS)
Jiao, Meiju; Sun, Limin
2011-04-01
Structural health monitoring (SHM) systems can provide valuable information for the evaluation of bridge performance. As the development and implementation of SHM technology in recent years, the data mining and use has received increasingly attention and interests in civil engineering. Based on the principle of probabilistic and statistics, a reliability approach provides a rational basis for analysis of the randomness in loads and their effects on structures. A novel approach combined SHM systems with reliability method to evaluate the reliability of a cable-stayed bridge instrumented with SHM systems was presented in this paper. In this study, the reliability of the steel girder of the cable-stayed bridge was denoted by failure probability directly instead of reliability index as commonly used. Under the assumption that the probability distributions of the resistance are independent to the responses of structures, a formulation of failure probability was deduced. Then, as a main factor in the formulation, the probability density function (PDF) of the strain at sensor locations based on the monitoring data was evaluated and verified. That Donghai Bridge was taken as an example for the application of the proposed approach followed. In the case study, 4 years' monitoring data since the operation of the SHM systems was processed, and the reliability assessment results were discussed. Finally, the sensitivity and accuracy of the novel approach compared with FORM was discussed.
Probabilistic confidence for decisions based on uncertain reliability estimates
NASA Astrophysics Data System (ADS)
Reid, Stuart G.
2013-05-01
Reliability assessments are commonly carried out to provide a rational basis for risk-informed decisions concerning the design or maintenance of engineering systems and structures. However, calculated reliabilities and associated probabilities of failure often have significant uncertainties associated with the possible estimation errors relative to the 'true' failure probabilities. For uncertain probabilities of failure, a measure of 'probabilistic confidence' has been proposed to reflect the concern that uncertainty about the true probability of failure could result in a system or structure that is unsafe and could subsequently fail. The paper describes how the concept of probabilistic confidence can be applied to evaluate and appropriately limit the probabilities of failure attributable to particular uncertainties such as design errors that may critically affect the dependability of risk-acceptance decisions. This approach is illustrated with regard to the dependability of structural design processes based on prototype testing with uncertainties attributable to sampling variability.
Estimating forest canopy fuel parameters using LIDAR data.
Hans-Erik Andersen; Robert J. McGaughey; Stephen E. Reutebuch
2005-01-01
Fire researchers and resource managers are dependent upon accurate, spatially-explicit forest structure information to support the application of forest fire behavior models. In particular, reliable estimates of several critical forest canopy structure metrics, including canopy bulk density, canopy height, canopy fuel weight, and canopy base height, are required to...
Concordance of DSM-IV Axis I and II diagnoses by personal and informant's interview.
Schneider, Barbara; Maurer, Konrad; Sargk, Dieter; Heiskel, Harald; Weber, Bernhard; Frölich, Lutz; Georgi, Klaus; Fritze, Jürgen; Seidler, Andreas
2004-06-30
The validity and reliability of using psychological autopsies to diagnose a psychiatric disorder is a critical issue. Therefore, interrater and test-retest reliability of the Structured Clinical Interview for DSM-IV Axis I and Personality Disorders and the usefulness of these instruments for the psychological autopsy method were investigated. Diagnoses by informant's interview were compared with diagnoses generated by a personal interview of 35 persons. Interrater reliability and test-retest reliability were assessed in 33 and 29 persons, respectively. Chi-square analysis, kappa and intraclass correlation coefficients, and Kendall's tau were used to determine agreement of diagnoses. Kappa coefficients were above 0.84 for substance-related disorders, mood disorders, and anxiety and adjustment disorders, and above 0.65 for Axis II disorders for interrater and test-retest reliability. Agreement by personal and relative's interview generated kappa coefficients above 0.79 for most Axis I and above 0.65 for most personality disorder diagnoses; Kendall's tau for dimensional individual personality disorder scores ranged from 0.22 to 0.72. Despite of a small number of psychiatric disorders in the selected population, the present results provide support for the validity of most diagnoses obtained through the best-estimate method using the Structured Clinical Interview for DSM-IV Axis I and Personality Disorders. This instrument can be recommended as a tool for the psychological autopsy procedure in post-mortem research. Copyright 2004 Elsevier Ireland Ltd.
Fiori, Simona; Cioni, Giovanni; Klingels, Katrjin; Ortibus, Els; Van Gestel, Leen; Rose, Stephen; Boyd, Roslyn N; Feys, Hilde; Guzzetta, Andrea
2014-09-01
To describe the development of a novel rating scale for classification of brain structural magnetic resonance imaging (MRI) in children with cerebral palsy (CP) and to assess its interrater and intrarater reliability. The scale consists of three sections. Section 1 contains descriptive information about the patient and MRI. Section 2 contains the graphical template of brain hemispheres onto which the lesion is transposed. Section 3 contains the scoring system for the quantitative analysis of the lesion characteristics, grouped into different global scores and subscores that assess separately side, regions, and depth. A larger interrater and intrarater reliability study was performed in 34 children with CP (22 males, 12 females; mean age at scan of 9 y 5 mo [SD 3 y 3 mo], range 4 y-16 y 11 mo; Gross Motor Function Classification System level I, [n=22], II [n=10], and level III [n=2]). Very high interrater and intrarater reliability of the total score was found with indices above 0.87. Reliability coefficients of the lobar and hemispheric subscores ranged between 0.53 and 0.95. Global scores for hemispheres, basal ganglia, brain stem, and corpus callosum showed reliability coefficients above 0.65. This study presents the first visual, semi-quantitative scale for classification of brain structural MRI in children with CP. The high degree of reliability of the scale supports its potential application for investigating the relationship between brain structure and function and examining treatment response according to brain lesion severity in children with CP. © 2014 Mac Keith Press.
The Role of Human Error in Design, Construction, and Reliability of Marine Structures.
1994-10-01
The 1979 Three Mile Island nuclear plant accident was largely a result of a failure to properly sort out and recognize critically important information...determinating the goals and objectives of the program and by evaluating and interpreting the results in terms of structural design, construction, and...67 Checking Models in Structural Design ....................................... 69 Nuclear Power Plants
Eighth DOD/NASA/FAA Conference on Fibrous Composites in Structural Design, Part 2
NASA Technical Reports Server (NTRS)
Starnes, James H., Jr. (Compiler); Bohon, Herman L. (Compiler); Garzon, Sherry B. (Compiler)
1990-01-01
Papers presented at the conference are compiled. The conference provided a forum for the scientific community to exchange composite structures design information and an opportunity to observe recent progress in composite structures design and technology. Part 2 contains papers related to the following subject areas: the application in design; methodology in design; and reliability in design.
Italian validation of the Amsterdam Preoperative Anxiety and Information Scale.
Buonanno, Pasquale; Laiola, Anna; Palumbo, Chiara; Spinelli, Gianmario; Terminiello, Virginia; Servillo, Giuseppe
2017-07-01
Preoperative anxiety is usually experienced by patients awaiting surgical procedures and it can negatively impact patient's outcome. The Amsterdam Preoperative Anxiety and Information Scale (APAIS) is a questionnaire created to identify anxious patients and their need for information: it has been translated and validated in many languages because of its reliability and ease of completion. To date, no Italian version of the APAIS has been produced; our aim was to translate and validate the APAIS in Italian. We produced an Italian version of the APAIS and we administered it to 110 patients undergoing elective surgery; we explored its structure by factor analysis and its reliability by Cronbach's alpha. We analyzed its external validity by confronting it to the Spielberg's State-Trait Anxiety Inventory (STAI). Sensitivity, specificity, and positive and negative predictive values of the Italian version of the APAIS were determined. The Italian version of the APAIS confirmed the original structure of the questionnaire and its internal consistency; it well correlated with the STAI-Y1, the subscale of the STAI which explore the anxiety "state." An APAIS score of 14 was found as best cutoff to distinguish anxious and non-anxious patients. The Italian translation of the APAIS showed psychometric properties similar to the original version. Its reliability and its efficiency make it a powerful tool even in Italian population to detect anxiety and need for information.
Statistical inference of protein structural alignments using information and compression.
Collier, James H; Allison, Lloyd; Lesk, Arthur M; Stuckey, Peter J; Garcia de la Banda, Maria; Konagurthu, Arun S
2017-04-01
Structural molecular biology depends crucially on computational techniques that compare protein three-dimensional structures and generate structural alignments (the assignment of one-to-one correspondences between subsets of amino acids based on atomic coordinates). Despite its importance, the structural alignment problem has not been formulated, much less solved, in a consistent and reliable way. To overcome these difficulties, we present here a statistical framework for the precise inference of structural alignments, built on the Bayesian and information-theoretic principle of Minimum Message Length (MML). The quality of any alignment is measured by its explanatory power-the amount of lossless compression achieved to explain the protein coordinates using that alignment. We have implemented this approach in MMLigner , the first program able to infer statistically significant structural alignments. We also demonstrate the reliability of MMLigner 's alignment results when compared with the state of the art. Importantly, MMLigner can also discover different structural alignments of comparable quality, a challenging problem for oligomers and protein complexes. Source code, binaries and an interactive web version are available at http://lcb.infotech.monash.edu.au/mmligner . arun.konagurthu@monash.edu. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com
A REVIEW OF EFFORTS TO ORGANIZE INFORMATION ABOUT HUMAN LEARNING, TRANSFER, AND RETENTION.
ERIC Educational Resources Information Center
GINSBERG, ROSE; AND OTHERS
FOURTEEN EFFORTS TO ORGANIZE AVAILABLE INFORMATION ON HUMAN LEARNING, TRANSFER, AND RETENTION ARE SUMMARIZED AND EVALUATED ON SIX CRITERIA--BEHAVIORAL SIGNIFICANCE OF CATEGORIES, SCOPE, OBJECTIVITY AND RELIABILITY OF CATEGORIES, PROGNOSIS FOR THE SYSTEM, LOGICAL STRUCTURE, AND HEURISTIC VALUE OF THE SYSTEM. ATTENTION IS GIVEN TO OTHER SOURCES OF…
APPRIS: annotation of principal and alternative splice isoforms
Rodriguez, Jose Manuel; Maietta, Paolo; Ezkurdia, Iakes; Pietrelli, Alessandro; Wesselink, Jan-Jaap; Lopez, Gonzalo; Valencia, Alfonso; Tress, Michael L.
2013-01-01
Here, we present APPRIS (http://appris.bioinfo.cnio.es), a database that houses annotations of human splice isoforms. APPRIS has been designed to provide value to manual annotations of the human genome by adding reliable protein structural and functional data and information from cross-species conservation. The visual representation of the annotations provided by APPRIS for each gene allows annotators and researchers alike to easily identify functional changes brought about by splicing events. In addition to collecting, integrating and analyzing reliable predictions of the effect of splicing events, APPRIS also selects a single reference sequence for each gene, here termed the principal isoform, based on the annotations of structure, function and conservation for each transcript. APPRIS identifies a principal isoform for 85% of the protein-coding genes in the GENCODE 7 release for ENSEMBL. Analysis of the APPRIS data shows that at least 70% of the alternative (non-principal) variants would lose important functional or structural information relative to the principal isoform. PMID:23161672
Turan, Bulent
2016-01-01
When judging whether a relationship partner can be counted on to "be there" when needed, people may draw upon knowledge structures to process relevant information. We examined one such knowledge structure using the prototype methodology: indicators of a partner who is likely to be there when needed. In the first study (N = 91), the structure, content, and reliability of the prototype of indicators were examined. Then, using a false recognition study (N = 77), we demonstrated that once activated, the prototype of indicators of a partner who is likely to be there when needed affects information processing. Thus, the prototype of indicators may shape how people process support-relevant information in everyday life, affecting relationship outcomes. Using this knowledge structure may help a person process relevant information quickly and with cognitive economy. However, it may also lead to biases in judgments in certain situations.
Judging nursing information on the WWW: a theoretical understanding.
Cader, Raffik; Campbell, Steve; Watson, Don
2009-09-01
This paper is a report of a study of the judgement processes nurses use when evaluating World Wide Web information related to nursing practice. The World Wide Web has increased the global accessibility of online health information. However, the variable nature of the quality of World Wide Web information and its perceived level of reliability may lead to misinformation. This makes demands on healthcare professionals, and on nurses in particular, to ensure that health information of reliable quality is selected for use in practice. A grounded theory approach was adopted. Semi-structured interviews and focus groups were used to collect data, between 2004 and 2005, from 20 nurses undertaking a postqualification graduate course at a university and 13 nurses from a local hospital in the United Kingdom. A theoretical framework emerged that gave insight into the judgement process nurses use when evaluating World Wide Web information. Participants broke the judgement process down into specific tasks. In addition, they used tacit, process and propositional knowledge and intuition, quasi-rational cognition and analysis to undertake these tasks. World Wide Web information cues, time available and nurses' critical skills were influencing factors in their judgement process. Addressing the issue of quality and reliability associated with World Wide Web information is a global challenge. This theoretical framework could contribute towards meeting this challenge.
A Reliability Estimation in Modeling Watershed Runoff With Uncertainties
NASA Astrophysics Data System (ADS)
Melching, Charles S.; Yen, Ben Chie; Wenzel, Harry G., Jr.
1990-10-01
The reliability of simulation results produced by watershed runoff models is a function of uncertainties in nature, data, model parameters, and model structure. A framework is presented here for using a reliability analysis method (such as first-order second-moment techniques or Monte Carlo simulation) to evaluate the combined effect of the uncertainties on the reliability of output hydrographs from hydrologic models. For a given event the prediction reliability can be expressed in terms of the probability distribution of the estimated hydrologic variable. The peak discharge probability for a watershed in Illinois using the HEC-1 watershed model is given as an example. The study of the reliability of predictions from watershed models provides useful information on the stochastic nature of output from deterministic models subject to uncertainties and identifies the relative contribution of the various uncertainties to unreliability of model predictions.
Rapid and reliable protein structure determination via chemical shift threading.
Hafsa, Noor E; Berjanskii, Mark V; Arndt, David; Wishart, David S
2018-01-01
Protein structure determination using nuclear magnetic resonance (NMR) spectroscopy can be both time-consuming and labor intensive. Here we demonstrate how chemical shift threading can permit rapid, robust, and accurate protein structure determination using only chemical shift data. Threading is a relatively old bioinformatics technique that uses a combination of sequence information and predicted (or experimentally acquired) low-resolution structural data to generate high-resolution 3D protein structures. The key motivations behind using NMR chemical shifts for protein threading lie in the fact that they are easy to measure, they are available prior to 3D structure determination, and they contain vital structural information. The method we have developed uses not only sequence and chemical shift similarity but also chemical shift-derived secondary structure, shift-derived super-secondary structure, and shift-derived accessible surface area to generate a high quality protein structure regardless of the sequence similarity (or lack thereof) to a known structure already in the PDB. The method (called E-Thrifty) was found to be very fast (often < 10 min/structure) and to significantly outperform other shift-based or threading-based structure determination methods (in terms of top template model accuracy)-with an average TM-score performance of 0.68 (vs. 0.50-0.62 for other methods). Coupled with recent developments in chemical shift refinement, these results suggest that protein structure determination, using only NMR chemical shifts, is becoming increasingly practical and reliable. E-Thrifty is available as a web server at http://ethrifty.ca .
Reliability study of refractory gate gallium arsenide MESFETS
NASA Technical Reports Server (NTRS)
Yin, J. C. W.; Portnoy, W. M.
1981-01-01
Refractory gate MESFET's were fabricated as an alternative to aluminum gate devices, which have been found to be unreliable as RF power amplifiers. In order to determine the reliability of the new structures, statistics of failure and information about mechanisms of failure in refractory gate MESFET's are given. Test transistors were stressed under conditions of high temperature and forward gate current to enhance failure. Results of work at 150 C and 275 C are reported.
Reliability study of refractory gate gallium arsenide MESFETS
NASA Astrophysics Data System (ADS)
Yin, J. C. W.; Portnoy, W. M.
Refractory gate MESFET's were fabricated as an alternative to aluminum gate devices, which have been found to be unreliable as RF power amplifiers. In order to determine the reliability of the new structures, statistics of failure and information about mechanisms of failure in refractory gate MESFET's are given. Test transistors were stressed under conditions of high temperature and forward gate current to enhance failure. Results of work at 150 C and 275 C are reported.
Quinn, Amity E; Rosen, Rochelle K; McGeary, John E; Amoa, Francine; Kranzler, Henry R; Francazio, Sarah; McGarvey, Stephen T; Swift, Robert M
2014-01-01
The aims of this study were to develop a bilingual version of the Semi-Structured Assessment for Drug Dependence and Alcoholism (SSADDA) in English and Samoan and determine the reliability of assessments of alcohol dependence in American Samoa. The study consisted of development and reliability-testing phases. In the development phase, the SSADDA alcohol module was translated and the translation was evaluated through cognitive interviews. In the reliability-testing phase, the bilingual SSADDA was administered to 40 ethnic Samoans, including a sub-sample of 26 individuals who were retested. Cognitive interviews indicated the initial translation was culturally and linguistically appropriate except items pertaining to alcohol tolerance, which were modified to reflect Samoan concepts. SSADDA reliability testing indicated diagnoses of DSM-III-R and DSM-IV alcohol dependence were reliable. Reliability varied by language of administration. The English/Samoan version of the SSADDA is appropriate for the diagnosis of DSM-III-R alcohol dependence, which may be useful in advancing research and public health efforts to address alcohol problems in American Samoa and the Western Pacific. The translation methods may inform researchers translating diagnostic and assessment tools into different languages and cultures. © The Author 2014. Medical Council on Alcohol and Oxford University Press. All rights reserved.
Spatial Correlations in Natural Scenes Modulate Response Reliability in Mouse Visual Cortex
Rikhye, Rajeev V.
2015-01-01
Intrinsic neuronal variability significantly limits information encoding in the primary visual cortex (V1). Certain stimuli can suppress this intertrial variability to increase the reliability of neuronal responses. In particular, responses to natural scenes, which have broadband spatiotemporal statistics, are more reliable than responses to stimuli such as gratings. However, very little is known about which stimulus statistics modulate reliable coding and how this occurs at the neural ensemble level. Here, we sought to elucidate the role that spatial correlations in natural scenes play in reliable coding. We developed a novel noise-masking method to systematically alter spatial correlations in natural movies, without altering their edge structure. Using high-speed two-photon calcium imaging in vivo, we found that responses in mouse V1 were much less reliable at both the single neuron and population level when spatial correlations were removed from the image. This change in reliability was due to a reorganization of between-neuron correlations. Strongly correlated neurons formed ensembles that reliably and accurately encoded visual stimuli, whereas reducing spatial correlations reduced the activation of these ensembles, leading to an unreliable code. Together with an ensemble-specific normalization model, these results suggest that the coordinated activation of specific subsets of neurons underlies the reliable coding of natural scenes. SIGNIFICANCE STATEMENT The natural environment is rich with information. To process this information with high fidelity, V1 neurons have to be robust to noise and, consequentially, must generate responses that are reliable from trial to trial. While several studies have hinted that both stimulus attributes and population coding may reduce noise, the details remain unclear. Specifically, what features of natural scenes are important and how do they modulate reliability? This study is the first to investigate the role of spatial correlations, which are a fundamental attribute of natural scenes, in shaping stimulus coding by V1 neurons. Our results provide new insights into how stimulus spatial correlations reorganize the correlated activation of specific ensembles of neurons to ensure accurate information processing in V1. PMID:26511254
NASA Technical Reports Server (NTRS)
Lee, Alice T.; Gunn, Todd; Pham, Tuan; Ricaldi, Ron
1994-01-01
This handbook documents the three software analysis processes the Space Station Software Analysis team uses to assess space station software, including their backgrounds, theories, tools, and analysis procedures. Potential applications of these analysis results are also presented. The first section describes how software complexity analysis provides quantitative information on code, such as code structure and risk areas, throughout the software life cycle. Software complexity analysis allows an analyst to understand the software structure, identify critical software components, assess risk areas within a software system, identify testing deficiencies, and recommend program improvements. Performing this type of analysis during the early design phases of software development can positively affect the process, and may prevent later, much larger, difficulties. The second section describes how software reliability estimation and prediction analysis, or software reliability, provides a quantitative means to measure the probability of failure-free operation of a computer program, and describes the two tools used by JSC to determine failure rates and design tradeoffs between reliability, costs, performance, and schedule.
ERIC Educational Resources Information Center
McAloney-Kocaman, Kareena; McPherson, Kerri
2017-01-01
Research Findings: Despite it being a widely accepted measure of social, emotional, and behavioral problems among children and young people, the factor structure underlying the Strengths and Difficulties Questionnaire (SDQ) is contested. Recent research has suggested a need to consider methodological bias in the SDQ, associated with the positive…
Review of Literature on Probability of Detection for Magnetic Particle Nondestructive Testing
2013-01-01
4 3.2 Offshore welded structures..................................................................................... 8 3.3 Aerospace...presented in Section 6. 2. Overview of Magnetic Particle Testing MPT is used in heavy engineering to inspect welds for surface-breaking... welded structures, and concluding with a summary of reliability information embedded in aerospace standards. 3.1 Aerospace It appears that the
Structural composite panel performance under long-term load
Theodore L. Laufenberg
1988-01-01
Information on the performance of wood-based structural composite panels under long-term load is currently needed to permit their use in engineered assemblies and systems. A broad assessment of the time-dependent properties of panels is critical for creating databases and models of the creep-rupture phenomenon that lead to reliability-based design procedures. This...
A safety-based decision making architecture for autonomous systems
NASA Technical Reports Server (NTRS)
Musto, Joseph C.; Lauderbaugh, L. K.
1991-01-01
Engineering systems designed specifically for space applications often exhibit a high level of autonomy in the control and decision-making architecture. As the level of autonomy increases, more emphasis must be placed on assimilating the safety functions normally executed at the hardware level or by human supervisors into the control architecture of the system. The development of a decision-making structure which utilizes information on system safety is detailed. A quantitative measure of system safety, called the safety self-information, is defined. This measure is analogous to the reliability self-information defined by McInroy and Saridis, but includes weighting of task constraints to provide a measure of both reliability and cost. An example is presented in which the safety self-information is used as a decision criterion in a mobile robot controller. The safety self-information is shown to be consistent with the entropy-based Theory of Intelligent Machines defined by Saridis.
Hosford, Charles C; Siders, William A
2010-10-01
Strategies to facilitate learning include using knowledge of students' learning style preferences to inform students and their teachers. Aims of this study were to evaluate the factor structure, internal consistency, and temporal stability of medical student responses to the Index of Learning Styles (ILS) and determine its appropriateness as an instrument for medical education. The ILS assesses preferences on four dimensions: sensing/intuitive information perceiving, visual/verbal information receiving, active/reflective information processing, and sequential/global information understanding. Students entering the 2002-2007 classes completed the ILS; some completed the ILS again after 2 and 4 years. Analyses of responses supported the ILS's intended structure and moderate reliability. Students had moderate preferences for sensing and visual learning. This study provides evidence supporting the appropriateness of the ILS for assessing learning style preferences in medical students.
The system of technical diagnostics of the industrial safety information network
NASA Astrophysics Data System (ADS)
Repp, P. V.
2017-01-01
This research is devoted to problems of safety of the industrial information network. Basic sub-networks, ensuring reliable operation of the elements of the industrial Automatic Process Control System, were identified. The core tasks of technical diagnostics of industrial information safety were presented. The structure of the technical diagnostics system of the information safety was proposed. It includes two parts: a generator of cyber-attacks and the virtual model of the enterprise information network. The virtual model was obtained by scanning a real enterprise network. A new classification of cyber-attacks was proposed. This classification enables one to design an efficient generator of cyber-attacks sets for testing the virtual modes of the industrial information network. The numerical method of the Monte Carlo (with LPτ - sequences of Sobol), and Markov chain was considered as the design method for the cyber-attacks generation algorithm. The proposed system also includes a diagnostic analyzer, performing expert functions. As an integrative quantitative indicator of the network reliability the stability factor (Kstab) was selected. This factor is determined by the weight of sets of cyber-attacks, identifying the vulnerability of the network. The weight depends on the frequency and complexity of cyber-attacks, the degree of damage, complexity of remediation. The proposed Kstab is an effective integral quantitative measure of the information network reliability.
NASA Astrophysics Data System (ADS)
Flanigan, Katherine A.; Johnson, Nephi R.; Hou, Rui; Ettouney, Mohammed; Lynch, Jerome P.
2017-04-01
The ability to quantitatively assess the condition of railroad bridges facilitates objective evaluation of their robustness in the face of hazard events. Of particular importance is the need to assess the condition of railroad bridges in networks that are exposed to multiple hazards. Data collected from structural health monitoring (SHM) can be used to better maintain a structure by prompting preventative (rather than reactive) maintenance strategies and supplying quantitative information to aid in recovery. To that end, a wireless monitoring system is validated and installed on the Harahan Bridge which is a hundred-year-old long-span railroad truss bridge that crosses the Mississippi River near Memphis, TN. This bridge is exposed to multiple hazards including scour, vehicle/barge impact, seismic activity, and aging. The instrumented sensing system targets non-redundant structural components and areas of the truss and floor system that bridge managers are most concerned about based on previous inspections and structural analysis. This paper details the monitoring system and the analytical method for the assessment of bridge condition based on automated data-driven analyses. Two primary objectives of monitoring the system performance are discussed: 1) monitoring fatigue accumulation in critical tensile truss elements; and 2) monitoring the reliability index values associated with sub-system limit states of these members. Moreover, since the reliability index is a scalar indicator of the safety of components, quantifiable condition assessment can be used as an objective metric so that bridge owners can make informed damage mitigation strategies and optimize resource management on single bridge or network levels.
Characterising RNA secondary structure space using information entropy
2013-01-01
Comparative methods for RNA secondary structure prediction use evolutionary information from RNA alignments to increase prediction accuracy. The model is often described in terms of stochastic context-free grammars (SCFGs), which generate a probability distribution over secondary structures. It is, however, unclear how this probability distribution changes as a function of the input alignment. As prediction programs typically only return a single secondary structure, better characterisation of the underlying probability space of RNA secondary structures is of great interest. In this work, we show how to efficiently compute the information entropy of the probability distribution over RNA secondary structures produced for RNA alignments by a phylo-SCFG, and implement it for the PPfold model. We also discuss interpretations and applications of this quantity, including how it can clarify reasons for low prediction reliability scores. PPfold and its source code are available from http://birc.au.dk/software/ppfold/. PMID:23368905
Object-oriented fault tree evaluation program for quantitative analyses
NASA Technical Reports Server (NTRS)
Patterson-Hine, F. A.; Koen, B. V.
1988-01-01
Object-oriented programming can be combined with fault free techniques to give a significantly improved environment for evaluating the safety and reliability of large complex systems for space missions. Deep knowledge about system components and interactions, available from reliability studies and other sources, can be described using objects that make up a knowledge base. This knowledge base can be interrogated throughout the design process, during system testing, and during operation, and can be easily modified to reflect design changes in order to maintain a consistent information source. An object-oriented environment for reliability assessment has been developed on a Texas Instrument (TI) Explorer LISP workstation. The program, which directly evaluates system fault trees, utilizes the object-oriented extension to LISP called Flavors that is available on the Explorer. The object representation of a fault tree facilitates the storage and retrieval of information associated with each event in the tree, including tree structural information and intermediate results obtained during the tree reduction process. Reliability data associated with each basic event are stored in the fault tree objects. The object-oriented environment on the Explorer also includes a graphical tree editor which was modified to display and edit the fault trees.
Out Brief for the Structural Reliability Partnership Workshop
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boyce, Brad; Fang, Eliot; Kolski, Alyssa
The Structural Reliability Partnership Workshop was held in Albuquerque, NM on August 29-30, 2017 and was hosted by Sandia National Laboratories. Attendees were present from academia, industry and several other national laboratories. The workshop kicked off with an introduction to the SRP to familiarize potential members with what the purpose, structure and benefits would be to their organization. Technical overviews were given on several topics by attendees from each sector – national labs, universities and industry – to provide a snapshot of the type of work that is currently being conducted on structural reliability. Attendees were then given the opportunitymore » to suggest and discuss potential Challenge Scenario topics. Three were ultimately decided upon as being the most important: Additive Manufacturing, Hydrogen Pipeline Steels, and Bolted Joined Structures. These were then analyzed using Quad Charts to determine What, How, Who, and Why these areas would be further investigated. Rather than restricting future research to only one area, the option was left open to investigate both the top two, depending on interest and cost associated with hosting such an event. More informal collaboration may be undertaken for the third topic if members have time and interest. Other items discussed pertained to the organization, structure and policies of the Partnership. Topics including Data Management, IP, and mechanisms of partnering/information sharing were touched upon but final decisions were not made. Further action is needed before this can be done. Action items were outlined and assigned, where possible. The next workshop is to be held in early August 2018 in Boulder, CO and is to be hosted by NIST. In the interim, quarterly updates are to take place via WebEx to maintain a line of communication and to ensure progress on both the administrative and technical tasks.« less
NASA Astrophysics Data System (ADS)
Popov, A.; Zolotarev, V.; Bychkov, S.
2016-11-01
This paper examines the results of experimental studies of a previously submitted combined algorithm designed to increase the reliability of information systems. The data that illustrates the organization and conduct of the studies is provided. Within the framework of a comparison of As a part of the study conducted, the comparison of the experimental data of simulation modeling and the data of the functioning of the real information system was made. The hypothesis of the homogeneity of the logical structure of the information systems was formulated, thus enabling to reconfigure the algorithm presented, - more specifically, to transform it into the model for the analysis and prediction of arbitrary information systems. The results presented can be used for further research in this direction. The data of the opportunity to predict the functioning of the information systems can be used for strategic and economic planning. The algorithm can be used as a means for providing information security.
Saito, Rintaro; Suzuki, Harukazu; Hayashizaki, Yoshihide
2003-04-12
Recent screening techniques have made large amounts of protein-protein interaction data available, from which biologically important information such as the function of uncharacterized proteins, the existence of novel protein complexes, and novel signal-transduction pathways can be discovered. However, experimental data on protein interactions contain many false positives, making these discoveries difficult. Therefore computational methods of assessing the reliability of each candidate protein-protein interaction are urgently needed. We developed a new 'interaction generality' measure (IG2) to assess the reliability of protein-protein interactions using only the topological properties of their interaction-network structure. Using yeast protein-protein interaction data, we showed that reliable protein-protein interactions had significantly lower IG2 values than less-reliable interactions, suggesting that IG2 values can be used to evaluate and filter interaction data to enable the construction of reliable protein-protein interaction networks.
Zheng, Y.
2013-01-01
Temporal sound cues are essential for sound recognition, pitch, rhythm, and timbre perception, yet how auditory neurons encode such cues is subject of ongoing debate. Rate coding theories propose that temporal sound features are represented by rate tuned modulation filters. However, overwhelming evidence also suggests that precise spike timing is an essential attribute of the neural code. Here we demonstrate that single neurons in the auditory midbrain employ a proportional code in which spike-timing precision and firing reliability covary with the sound envelope cues to provide an efficient representation of the stimulus. Spike-timing precision varied systematically with the timescale and shape of the sound envelope and yet was largely independent of the sound modulation frequency, a prominent cue for pitch. In contrast, spike-count reliability was strongly affected by the modulation frequency. Spike-timing precision extends from sub-millisecond for brief transient sounds up to tens of milliseconds for sounds with slow-varying envelope. Information theoretic analysis further confirms that spike-timing precision depends strongly on the sound envelope shape, while firing reliability was strongly affected by the sound modulation frequency. Both the information efficiency and total information were limited by the firing reliability and spike-timing precision in a manner that reflected the sound structure. This result supports a temporal coding strategy in the auditory midbrain where proportional changes in spike-timing precision and firing reliability can efficiently signal shape and periodicity temporal cues. PMID:23636724
Bachmann, Monica; de Boer, Wout; Schandelmaier, Stefan; Leibold, Andrea; Marelli, Renato; Jeger, Joerg; Hoffmann-Richter, Ulrike; Mager, Ralph; Schaad, Heinz; Zumbrunn, Thomas; Vogel, Nicole; Bänziger, Oskar; Busse, Jason W; Fischer, Katrin; Kunz, Regina
2016-07-29
Work capacity evaluations by independent medical experts are widely used to inform insurers whether injured or ill workers are capable of engaging in competitive employment. In many countries, evaluation processes lack a clearly structured approach, standardized instruments, and an explicit focus on claimants' functional abilities. Evaluation of subjective complaints, such as mental illness, present additional challenges in the determination of work capacity. We have therefore developed a process for functional evaluation of claimants with mental disorders which complements usual psychiatric evaluation. Here we report the design of a study to measure the reliability of our approach in determining work capacity among patients with mental illness applying for disability benefits. We will conduct a multi-center reliability study, in which 20 psychiatrists trained in our functional evaluation process will assess 30 claimants presenting with mental illness for eligibility to receive disability benefits [Reliability of Functional Evaluation in Psychiatry, RELY-study]. The functional evaluation process entails a five-step structured interview and a reporting instrument (Instrument of Functional Assessment in Psychiatry [IFAP]) to document the severity of work-related functional limitations. We will videotape all evaluations which will be viewed by three psychiatrists who will independently rate claimants' functional limitations. Our primary outcome measure is the evaluation of claimant's work capacity as a percentage (0 to 100 %), and our secondary outcomes are the 12 mental functions and 13 functional capacities assessed by the IFAP-instrument. Inter-rater reliability of four psychiatric experts will be explored using multilevel models to estimate the intraclass correlation coefficient (ICC). Additional analyses include subgroups according to mental disorder, the typicality of claimants, and claimant perceived fairness of the assessment process. We hypothesize that a structured functional approach will show moderate reliability (ICC ≥ 0.6) of psychiatric evaluation of work capacity. Enrollment of actual claimants with mental disorders referred for evaluation by disability/accident insurers will increase the external validity of our findings. Finding moderate levels of reliability, we will continue with a randomized trial to test the reliability of a structured functional approach versus evaluation-as-usual.
Deducing chemical structure from crystallographically determined atomic coordinates
Bruno, Ian J.; Shields, Gregory P.; Taylor, Robin
2011-01-01
An improved algorithm has been developed for assigning chemical structures to incoming entries to the Cambridge Structural Database, using only the information available in the deposited CIF. Steps in the algorithm include detection of bonds, selection of polymer unit, resolution of disorder, and assignment of bond types and formal charges. The chief difficulty is posed by the large number of metallo-organic crystal structures that must be processed, given our aspiration that assigned chemical structures should accurately reflect properties such as the oxidation states of metals and redox-active ligands, metal coordination numbers and hapticities, and the aromaticity or otherwise of metal ligands. Other complications arise from disorder, especially when it is symmetry imposed or modelled with the SQUEEZE algorithm. Each assigned structure is accompanied by an estimate of reliability and, where necessary, diagnostic information indicating probable points of error. Although the algorithm was written to aid building of the Cambridge Structural Database, it has the potential to develop into a general-purpose tool for adding chemical information to newly determined crystal structures. PMID:21775812
Universal first-order reliability concept applied to semistatic structures
NASA Technical Reports Server (NTRS)
Verderaime, V.
1994-01-01
A reliability design concept was developed for semistatic structures which combines the prevailing deterministic method with the first-order reliability method. The proposed method surmounts deterministic deficiencies in providing uniformly reliable structures and improved safety audits. It supports risk analyses and reliability selection criterion. The method provides a reliability design factor derived from the reliability criterion which is analogous to the current safety factor for sizing structures and verifying reliability response. The universal first-order reliability method should also be applicable for air and surface vehicles semistatic structures.
Universal first-order reliability concept applied to semistatic structures
NASA Astrophysics Data System (ADS)
Verderaime, V.
1994-07-01
A reliability design concept was developed for semistatic structures which combines the prevailing deterministic method with the first-order reliability method. The proposed method surmounts deterministic deficiencies in providing uniformly reliable structures and improved safety audits. It supports risk analyses and reliability selection criterion. The method provides a reliability design factor derived from the reliability criterion which is analogous to the current safety factor for sizing structures and verifying reliability response. The universal first-order reliability method should also be applicable for air and surface vehicles semistatic structures.
Finnerty, Justin John; Peyser, Alexander; Carloni, Paolo
2015-01-01
Cation selective channels constitute the gate for ion currents through the cell membrane. Here we present an improved statistical mechanical model based on atomistic structural information, cation hydration state and without tuned parameters that reproduces the selectivity of biological Na+ and Ca2+ ion channels. The importance of the inclusion of step-wise cation hydration in these results confirms the essential role partial dehydration plays in the bacterial Na+ channels. The model, proven reliable against experimental data, could be straightforwardly used for designing Na+ and Ca2+ selective nanopores.
Structural Damage Detection Using Virtual Passive Controllers
NASA Technical Reports Server (NTRS)
Lew, Jiann-Shiun; Juang, Jer-Nan
2001-01-01
This paper presents novel approaches for structural damage detection which uses the virtual passive controllers attached to structures, where passive controllers are energy dissipative devices and thus guarantee the closed-loop stability. The use of the identified parameters of various closed-loop systems can solve the problem that reliable identified parameters, such as natural frequencies of the open-loop system may not provide enough information for damage detection. Only a small number of sensors are required for the proposed approaches. The identified natural frequencies, which are generally much less sensitive to noise and more reliable than the identified natural frequencies, are used for damage detection. Two damage detection techniques are presented. One technique is based on the structures with direct output feedback controllers while the other technique uses the second-order dynamic feedback controllers. A least-squares technique, which is based on the sensitivity of natural frequencies to damage variables, is used for accurately identifying the damage variables.
NASA Technical Reports Server (NTRS)
Wong, P. K.
1975-01-01
The closely-related problems of designing reliable feedback stabilization strategy and coordinating decentralized feedbacks are considered. Two approaches are taken. A geometric characterization of the structure of control interaction (and its dual) was first attempted and a concept of structural homomorphism developed based on the idea of 'similarity' of interaction pattern. The idea of finding classes of individual feedback maps that do not 'interfere' with the stabilizing action of each other was developed by identifying the structural properties of nondestabilizing and LQ-optimal feedback maps. Some known stability properties of LQ-feedback were generalized and some partial solutions were provided to the reliable stabilization and decentralized feedback coordination problems. A concept of coordination parametrization was introduced, and a scheme for classifying different modes of decentralization (information, control law computation, on-line control implementation) in control systems was developed.
Powell-Young, Yolanda M; Spruill, Ida J
2011-12-01
The purpose of this investigation was to examine the reliability and factor structure of the Harter Self-Perception Profile for Adolescents (SPPA) with African-Americans. While the SPPA has demonstrated strong psychometric properties with European-Americans, limited information exists with African-Americans. Three hundred and ten (N = 310) female adolescents, from 14 through 18 years of age, completed the SPPA. Estimations of internal consistency reliability with Cronbach's alpha (alpha), item suitability with Pearson (gamma) correlations, and evaluation of factor structure fit utilizing principle axis extraction with oblimin (oblique) rotation were conducted. When compared with Harter's normative data, psychometric properties of the SPPA varied significantly with the current sample. Findings suggested cautious interpretation of data generated with demographically similar cohorts. Further study is warranted to ascertain the factor structure that is most relevant for use with African-American adolescents.
The neural processing of hierarchical structure in music and speech at different timescales.
Farbood, Morwaread M; Heeger, David J; Marcus, Gary; Hasson, Uri; Lerner, Yulia
2015-01-01
Music, like speech, is a complex auditory signal that contains structures at multiple timescales, and as such is a potentially powerful entry point into the question of how the brain integrates complex streams of information. Using an experimental design modeled after previous studies that used scrambled versions of a spoken story (Lerner et al., 2011) and a silent movie (Hasson et al., 2008), we investigate whether listeners perceive hierarchical structure in music beyond short (~6 s) time windows and whether there is cortical overlap between music and language processing at multiple timescales. Experienced pianists were presented with an extended musical excerpt scrambled at multiple timescales-by measure, phrase, and section-while measuring brain activity with functional magnetic resonance imaging (fMRI). The reliability of evoked activity, as quantified by inter-subject correlation of the fMRI responses, was measured. We found that response reliability depended systematically on musical structure coherence, revealing a topographically organized hierarchy of processing timescales. Early auditory areas (at the bottom of the hierarchy) responded reliably in all conditions. For brain areas at the top of the hierarchy, the original (unscrambled) excerpt evoked more reliable responses than any of the scrambled excerpts, indicating that these brain areas process long-timescale musical structures, on the order of minutes. The topography of processing timescales was analogous with that reported previously for speech, but the timescale gradients for music and speech overlapped with one another only partially, suggesting that temporally analogous structures-words/measures, sentences/musical phrases, paragraph/sections-are processed separately.
Peer Evaluation Can Reliably Measure Local Knowledge
ERIC Educational Resources Information Center
Reyes-García, Victoria; Díaz-Reviriego, Isabel; Duda, Romain; Fernández-Llamazares, Álvaro; Gallois, Sandrine; Guèze, Maximilien; Napitupulu, Lucentezza; Pyhälä, Aili
2016-01-01
We assess the consistency of measures of individual local ecological knowledge obtained through peer evaluation against three standard measures: identification tasks, structured questionnaires, and self-reported skills questionnaires. We collected ethnographic information among the Baka (Congo), the Punan (Borneo), and the Tsimane' (Amazon) to…
Health e-mavens: identifying active online health information users.
Sun, Ye; Liu, Miao; Krakow, Melinda
2016-10-01
Given the rapid increase of Internet use for effective health communication, it is important for health practitioners to be able to identify and mobilize active users of online health information across various web-based health intervention programmes. We propose the concept 'health e-mavens' to characterize individuals actively engaged in online health information seeking and sharing activities. This study aimed to address three goals: (i) to test the factor structure of health e-mavenism, (ii) to assess the reliability and validity of this construct and (iii) to determine what predictors are associated with health e-mavenism. This study was a secondary analysis of nationally representative data from the 2010 Health Tracking Survey. We assessed the factor structure of health e-mavenism using confirmatory factor analysis and examined socio-demographic variables, health-related factors and use of technology as potential predictors of health e-mavenism through ordered regression analysis. Confirmatory factor analyses showed that a second-order two-factor structure best captured the health e-maven construct. Health e-mavenism comprised two second-order factors, each encompassing two first-order dimensions: information acquisition (consisting of information tracking and consulting) and information transmission (consisting of information posting and sharing). Both first-order and second-order factors exhibited good reliabilities. Several factors were found to be significant predictors of health e-mavenism. This study offers a starting point for further inquiries about health e-mavens. It is a fruitful construct for health promotion research in the age of new media technologies. We conclude with specific recommendations to further develop the health e-maven concept through continued empirical research. © 2015 The Authors. Health Expectations. Published by John Wiley & Sons Ltd.
Karimi, Fatemeh Zahra; Alesheikh, Aytay; Pakravan, Soheila; Abdollahi, Mahbubeh; Damough, Mozhdeh; Anbaran, Zahra Khosravi; Farahani, Leila Amiri
2017-10-01
In medical sciences, commitment to lifelong learning has been expressed as an important element. Today, due to the rapid development of medical information and technology, lifelong learning is critical for safe medical care and development in medical research. JeffSPLL is one of the scales for measuring lifelong learning among the staff of medical sciences that has never been used in Iran. The aim of the present study was to determine the factor structure and reliability of the Persian version of JeffSPLL among Persian-speaking staff of universities of medical sciences in Iran. This study was a cross-sectional study, methodologically, that was conducted in 2012-2013. In this study, 210 staff members of Birjand University of Medical Sciences were selected. Data collection tool was the Persian version of JeffSPLL. To investigate the factor structure of this tool, confirmatory factor analysis was used and to evaluate the model fit, goodness-of-fit indices, root mean square error of approximation (RMSEA), the ratio of chi-square to the degree of freedom associated with it, comparative fit index (CFI), and root mean square residual (RMR) were used. To investigate the reliability of tool, Cronbach's alpha was employed. Data analysis was conducted using LISREL8.8 and SPSS 20 software. Confirmatory factor analysis showed that RMSEA was close to 0.1, and CFI and GFI were close to one. Therefore, four-factor model was appropriate. Cronbach's alpha was 0.92 for the whole tool and it was between 0.82 and 0.89 for subscales. The present study verified the four-factor structure of the 19-item Persian version of JeffSPLL that included professional learning beliefs and motivation, scholarly activities, attention to learning opportunities, and technical skills in information seeking among the staff. In addition, this tool has acceptable reliability. Therefore, it was appropriate to assess lifelong learning in the Persian-speaking staff population.
An automated distinction of DICOM images for lung cancer CAD system
NASA Astrophysics Data System (ADS)
Suzuki, H.; Saita, S.; Kubo, M.; Kawata, Y.; Niki, N.; Nishitani, H.; Ohmatsu, H.; Eguchi, K.; Kaneko, M.; Moriyama, N.
2009-02-01
Automated distinction of medical images is an important preprocessing in Computer-Aided Diagnosis (CAD) systems. The CAD systems have been developed using medical image sets with specific scan conditions and body parts. However, varied examinations are performed in medical sites. The specification of the examination is contained into DICOM textual meta information. Most DICOM textual meta information can be considered reliable, however the body part information cannot always be considered reliable. In this paper, we describe an automated distinction of DICOM images as a preprocessing for lung cancer CAD system. Our approach uses DICOM textual meta information and low cost image processing. Firstly, the textual meta information such as scan conditions of DICOM image is distinguished. Secondly, the DICOM image is set to distinguish the body parts which are identified by image processing. The identification of body parts is based on anatomical structure which is represented by features of three regions, body tissue, bone, and air. The method is effective to the practical use of lung cancer CAD system in medical sites.
Guillaume, François; Fritz, Sébastien; Boichard, Didier; Druet, Tom
2008-01-01
The efficiency of the French marker-assisted selection (MAS) was estimated by a simulation study. The data files of two different time periods were used: April 2004 and 2006. The simulation method used the structure of the existing French MAS: same pedigree, same marker genotypes and same animals with records. The program simulated breeding values and new records based on this existing structure and knowledge on the QTL used in MAS (variance and frequency). Reliabilities of genetic values of young animals (less than one year old) obtained with and without marker information were compared to assess the efficiency of MAS for evaluation of milk, fat and protein yields and fat and protein contents. Mean gains of reliability ranged from 0.015 to 0.094 and from 0.038 to 0.114 in 2004 and 2006, respectively. The larger number of animals genotyped and the use of a new set of genetic markers can explain the improvement of MAS reliability from 2004 to 2006. This improvement was also observed by analysis of information content for young candidates. The gain of MAS reliability with respect to classical selection was larger for sons of sires with genotyped progeny daughters with records. Finally, it was shown that when superiority of MAS over classical selection was estimated with daughter yield deviations obtained after progeny test instead of true breeding values, the gain was underestimated. PMID:18096117
Estimating future flood frequency and magnitude in basins affected by glacier wastage.
DOT National Transportation Integrated Search
2014-10-01
Infrastructure, such as bridge crossings, requires informed structural designs in order to be effective and reliable for : decades. A typical bridge is intended to operate for 75 years or more, a period of time anticipated to exhibit a warming : clim...
NASA Astrophysics Data System (ADS)
Chenghua, Ou; Chaochun, Li; Siyuan, Huang; Sheng, James J.; Yuan, Xu
2017-12-01
As the platform-based horizontal well production mode has been widely applied in petroleum industry, building a reliable fine reservoir structure model by using horizontal well stratigraphic correlation has become very important. Horizontal wells usually extend between the upper and bottom boundaries of the target formation, with limited penetration points. Using these limited penetration points to conduct well deviation correction means the formation depth information obtained is not accurate, which makes it hard to build a fine structure model. In order to solve this problem, a method of fine reservoir structure modeling, based on 3D visualized stratigraphic correlation among horizontal wells, is proposed. This method can increase the accuracy when estimating the depth of the penetration points, and can also effectively predict the top and bottom interfaces in the horizontal penetrating section. Moreover, this method will greatly increase not only the number of points of depth data available, but also the accuracy of these data, which achieves the goal of building a reliable fine reservoir structure model by using the stratigraphic correlation among horizontal wells. Using this method, four 3D fine structure layer models have been successfully built of a specimen shale gas field with platform-based horizontal well production mode. The shale gas field is located to the east of Sichuan Basin, China; the successful application of the method has proven its feasibility and reliability.
Integrating structure-based and ligand-based approaches for computational drug design.
Wilson, Gregory L; Lill, Markus A
2011-04-01
Methods utilized in computer-aided drug design can be classified into two major categories: structure based and ligand based, using information on the structure of the protein or on the biological and physicochemical properties of bound ligands, respectively. In recent years there has been a trend towards integrating these two methods in order to enhance the reliability and efficiency of computer-aided drug-design approaches by combining information from both the ligand and the protein. This trend resulted in a variety of methods that include: pseudoreceptor methods, pharmacophore methods, fingerprint methods and approaches integrating docking with similarity-based methods. In this article, we will describe the concepts behind each method and selected applications.
Reliability Analysis of a Glacier Lake Warning System Using a Bayesian Net
NASA Astrophysics Data System (ADS)
Sturny, Rouven A.; Bründl, Michael
2013-04-01
Beside structural mitigation measures like avalanche defense structures, dams and galleries, warning and alarm systems have become important measures for dealing with Alpine natural hazards. Integrating them into risk mitigation strategies and comparing their effectiveness with structural measures requires quantification of the reliability of these systems. However, little is known about how reliability of warning systems can be quantified and which methods are suitable for comparing their contribution to risk reduction with that of structural mitigation measures. We present a reliability analysis of a warning system located in Grindelwald, Switzerland. The warning system was built for warning and protecting residents and tourists from glacier outburst floods as consequence of a rapid drain of the glacier lake. We have set up a Bayesian Net (BN, BPN) that allowed for a qualitative and quantitative reliability analysis. The Conditional Probability Tables (CPT) of the BN were determined according to manufacturer's reliability data for each component of the system as well as by assigning weights for specific BN nodes accounting for information flows and decision-making processes of the local safety service. The presented results focus on the two alerting units 'visual acoustic signal' (VAS) and 'alerting of the intervention entities' (AIE). For the summer of 2009, the reliability was determined to be 94 % for the VAS and 83 % for the AEI. The probability of occurrence of a major event was calculated as 0.55 % per day resulting in an overall reliability of 99.967 % for the VAS and 99.906 % for the AEI. We concluded that a failure of the VAS alerting unit would be the consequence of a simultaneous failure of the four probes located in the lake and the gorge. Similarly, we deduced that the AEI would fail either if there were a simultaneous connectivity loss of the mobile and fixed network in Grindelwald, an Internet access loss or a failure of the regional operations centre. However, the probability of a common failure of these components was assumed to be low. Overall it can be stated that due to numerous redundancies, the investigated warning system is highly reliable and its influence on risk reduction is very high. Comparable studies in the future are needed to classify these results and to gain more experience how the reliability of warning systems could be determined in practice.
NASA Astrophysics Data System (ADS)
Wada, Daichi; Sugimoto, Yohei
2017-04-01
Aerodynamic loads on aircraft wings are one of the key parameters to be monitored for reliable and effective aircraft operations and management. Flight data of the aerodynamic loads would be used onboard to control the aircraft and accumulated data would be used for the condition-based maintenance and the feedback for the fatigue and critical load modeling. The effective sensing techniques such as fiber optic distributed sensing have been developed and demonstrated promising capability of monitoring structural responses, i.e., strains on the surface of the aircraft wings. By using the developed techniques, load identification methods for structural health monitoring are expected to be established. The typical inverse analysis for load identification using strains calculates the loads in a discrete form of concentrated forces, however, the distributed form of the loads is essential for the accurate and reliable estimation of the critical stress at structural parts. In this study, we demonstrate an inverse analysis to identify the distributed loads from measured strain information. The introduced inverse analysis technique calculates aerodynamic loads not in a discrete but in a distributed manner based on a finite element model. In order to verify the technique through numerical simulations, we apply static aerodynamic loads on a flat panel model, and conduct the inverse identification of the load distributions. We take two approaches to build the inverse system between loads and strains. The first one uses structural models and the second one uses neural networks. We compare the performance of the two approaches, and discuss the effect of the amount of the strain sensing information.
Finnerty, Justin John
2015-01-01
Cation selective channels constitute the gate for ion currents through the cell membrane. Here we present an improved statistical mechanical model based on atomistic structural information, cation hydration state and without tuned parameters that reproduces the selectivity of biological Na+ and Ca2+ ion channels. The importance of the inclusion of step-wise cation hydration in these results confirms the essential role partial dehydration plays in the bacterial Na+ channels. The model, proven reliable against experimental data, could be straightforwardly used for designing Na+ and Ca2+ selective nanopores. PMID:26460827
The neural processing of hierarchical structure in music and speech at different timescales
Farbood, Morwaread M.; Heeger, David J.; Marcus, Gary; Hasson, Uri; Lerner, Yulia
2015-01-01
Music, like speech, is a complex auditory signal that contains structures at multiple timescales, and as such is a potentially powerful entry point into the question of how the brain integrates complex streams of information. Using an experimental design modeled after previous studies that used scrambled versions of a spoken story (Lerner et al., 2011) and a silent movie (Hasson et al., 2008), we investigate whether listeners perceive hierarchical structure in music beyond short (~6 s) time windows and whether there is cortical overlap between music and language processing at multiple timescales. Experienced pianists were presented with an extended musical excerpt scrambled at multiple timescales—by measure, phrase, and section—while measuring brain activity with functional magnetic resonance imaging (fMRI). The reliability of evoked activity, as quantified by inter-subject correlation of the fMRI responses, was measured. We found that response reliability depended systematically on musical structure coherence, revealing a topographically organized hierarchy of processing timescales. Early auditory areas (at the bottom of the hierarchy) responded reliably in all conditions. For brain areas at the top of the hierarchy, the original (unscrambled) excerpt evoked more reliable responses than any of the scrambled excerpts, indicating that these brain areas process long-timescale musical structures, on the order of minutes. The topography of processing timescales was analogous with that reported previously for speech, but the timescale gradients for music and speech overlapped with one another only partially, suggesting that temporally analogous structures—words/measures, sentences/musical phrases, paragraph/sections—are processed separately. PMID:26029037
Ko, Junsu; Park, Hahnbeom; Seok, Chaok
2012-08-10
Protein structures can be reliably predicted by template-based modeling (TBM) when experimental structures of homologous proteins are available. However, it is challenging to obtain structures more accurate than the single best templates by either combining information from multiple templates or by modeling regions that vary among templates or are not covered by any templates. We introduce GalaxyTBM, a new TBM method in which the more reliable core region is modeled first from multiple templates and less reliable, variable local regions, such as loops or termini, are then detected and re-modeled by an ab initio method. This TBM method is based on "Seok-server," which was tested in CASP9 and assessed to be amongst the top TBM servers. The accuracy of the initial core modeling is enhanced by focusing on more conserved regions in the multiple-template selection and multiple sequence alignment stages. Additional improvement is achieved by ab initio modeling of up to 3 unreliable local regions in the fixed framework of the core structure. Overall, GalaxyTBM reproduced the performance of Seok-server, with GalaxyTBM and Seok-server resulting in average GDT-TS of 68.1 and 68.4, respectively, when tested on 68 single-domain CASP9 TBM targets. For application to multi-domain proteins, GalaxyTBM must be combined with domain-splitting methods. Application of GalaxyTBM to CASP9 targets demonstrates that accurate protein structure prediction is possible by use of a multiple-template-based approach, and ab initio modeling of variable regions can further enhance the model quality.
Reliability Quantification of Advanced Stirling Convertor (ASC) Components
NASA Technical Reports Server (NTRS)
Shah, Ashwin R.; Korovaichuk, Igor; Zampino, Edward
2010-01-01
The Advanced Stirling Convertor, is intended to provide power for an unmanned planetary spacecraft and has an operational life requirement of 17 years. Over this 17 year mission, the ASC must provide power with desired performance and efficiency and require no corrective maintenance. Reliability demonstration testing for the ASC was found to be very limited due to schedule and resource constraints. Reliability demonstration must involve the application of analysis, system and component level testing, and simulation models, taken collectively. Therefore, computer simulation with limited test data verification is a viable approach to assess the reliability of ASC components. This approach is based on physics-of-failure mechanisms and involves the relationship among the design variables based on physics, mechanics, material behavior models, interaction of different components and their respective disciplines such as structures, materials, fluid, thermal, mechanical, electrical, etc. In addition, these models are based on the available test data, which can be updated, and analysis refined as more data and information becomes available. The failure mechanisms and causes of failure are included in the analysis, especially in light of the new information, in order to develop guidelines to improve design reliability and better operating controls to reduce the probability of failure. Quantified reliability assessment based on fundamental physical behavior of components and their relationship with other components has demonstrated itself to be a superior technique to conventional reliability approaches based on utilizing failure rates derived from similar equipment or simply expert judgment.
Photovoltaic Reliability Workshop Lodging Information | Photovoltaic
Research | NREL Photovoltaic Reliability Workshop Lodging Information Photovoltaic Reliability Workshop Lodging Information The 2018 Photovoltaic Reliability Workshop (PVRW) will be held Tuesday
New structural information on food allergens (abstract)
USDA-ARS?s Scientific Manuscript database
A small number of protein families are responsible for food allergies suffered by the majority of allergy patients. What properties of these proteins make them allergens is not clear at present. Reliable methods for allergen prediction and mitigation are lacking. Most the immediate type of food alle...
E-MSD: an integrated data resource for bioinformatics.
Velankar, S; McNeil, P; Mittard-Runte, V; Suarez, A; Barrell, D; Apweiler, R; Henrick, K
2005-01-01
The Macromolecular Structure Database (MSD) group (http://www.ebi.ac.uk/msd/) continues to enhance the quality and consistency of macromolecular structure data in the worldwide Protein Data Bank (wwPDB) and to work towards the integration of various bioinformatics data resources. One of the major obstacles to the improved integration of structural databases such as MSD and sequence databases like UniProt is the absence of up to date and well-maintained mapping between corresponding entries. We have worked closely with the UniProt group at the EBI to clean up the taxonomy and sequence cross-reference information in the MSD and UniProt databases. This information is vital for the reliable integration of the sequence family databases such as Pfam and Interpro with the structure-oriented databases of SCOP and CATH. This information has been made available to the eFamily group (http://www.efamily.org.uk/) and now forms the basis of the regular interchange of information between the member databases (MSD, UniProt, Pfam, Interpro, SCOP and CATH). This exchange of annotation information has enriched the structural information in the MSD database with annotation from wider sequence-oriented resources. This work was carried out under the 'Structure Integration with Function, Taxonomy and Sequences (SIFTS)' initiative (http://www.ebi.ac.uk/msd-srv/docs/sifts) in the MSD group.
Autonomous System for Monitoring the Integrity of Composite Fan Housings
NASA Technical Reports Server (NTRS)
Qing, Xinlin P.; Aquino, Christopher; Kumar, Amrita
2010-01-01
A low-cost and reliable system assesses the integrity of composite fan-containment structures. The system utilizes a network of miniature sensors integrated with the structure to scan the entire structural area for any impact events and resulting structural damage, and to monitor degradation due to usage. This system can be used to monitor all types of composite structures on aircraft and spacecraft, as well as automatically monitor in real time the location and extent of damage in the containment structures. This diagnostic information is passed to prognostic modeling that is being developed to utilize the information and provide input on the residual strength of the structure, and maintain a history of structural degradation during usage. The structural health-monitoring system would consist of three major components: (1) sensors and a sensor network, which is permanently bonded onto the structure being monitored; (2) integrated hardware; and (3) software to monitor in-situ the health condition of in-service structures.
Structural reliability assessment capability in NESSUS
NASA Technical Reports Server (NTRS)
Millwater, H.; Wu, Y.-T.
1992-01-01
The principal capabilities of NESSUS (Numerical Evaluation of Stochastic Structures Under Stress), an advanced computer code developed for probabilistic structural response analysis, are reviewed, and its structural reliability assessed. The code combines flexible structural modeling tools with advanced probabilistic algorithms in order to compute probabilistic structural response and resistance, component reliability and risk, and system reliability and risk. An illustrative numerical example is presented.
Structural reliability assessment capability in NESSUS
NASA Astrophysics Data System (ADS)
Millwater, H.; Wu, Y.-T.
1992-07-01
The principal capabilities of NESSUS (Numerical Evaluation of Stochastic Structures Under Stress), an advanced computer code developed for probabilistic structural response analysis, are reviewed, and its structural reliability assessed. The code combines flexible structural modeling tools with advanced probabilistic algorithms in order to compute probabilistic structural response and resistance, component reliability and risk, and system reliability and risk. An illustrative numerical example is presented.
Psychometric Properties of the Canadian Nurse Informatics Competency Assessment Scale.
Kleib, Manal; Nagle, Lynn
2018-04-10
Assessment of nursing informatics competencies has gained momentum in the scholarly literature in response to the increased need for resources available to support informatics capacity in nursing. The purpose of this study was to examine the factor structure and internal consistency reliability of the Canadian Nurse Informatics Competency Assessment Scale, a newly developed 21-item measure based on published entry-to-practice informatics competencies for RNs. For this study, 2844 nurses completed the Canadian Nurse Informatics Competency Assessment Scale through a cross-sectional survey. Exploratory principal component analysis with oblique promax rotation revealed a four-component/factor structure for the 21-item Canadian Nurse Informatics Competency Assessment Scale, explaining 61.04% of the variance. Item loading per each component reflected the original Canadian Association of Schools of Nursing grouping of nursing informatics competency indicators, as per three key domains of competency: information and knowledge management (α = .85); professional and regulatory accountability (α = .81); and use of information and communication technology in the delivery of patient care (α = .87) with the exception of one item (Indicator 3), which loaded into the category of foundational information and communication technology skills (α = .81). This study provided preliminary evidence for the construct validity of the entry-to-practice competency domains and the factor structure and reliability of the Canadian Nurse Informatics Competency Assessment Scale among practicing nurses. Further testing among nurses in other settings and among nursing students is recommended.
ERIC Educational Resources Information Center
National Bureau of Standards (DOC), Washington, DC.
These guidelines provide a handbook for use by federal organizations in structuring physical security and risk management programs for their automatic data processing facilities. This publication discusses security analysis, natural disasters, supporting utilities, system reliability, procedural measures and controls, off-site facilities,…
Commentary on Coefficient Alpha: A Cautionary Tale
ERIC Educational Resources Information Center
Green, Samuel B.; Yang, Yanyun
2009-01-01
The general use of coefficient alpha to assess reliability should be discouraged on a number of grounds. The assumptions underlying coefficient alpha are unlikely to hold in practice, and violation of these assumptions can result in nontrivial negative or positive bias. Structural equation modeling was discussed as an informative process both to…
A fingerprint classification algorithm based on combination of local and global information
NASA Astrophysics Data System (ADS)
Liu, Chongjin; Fu, Xiang; Bian, Junjie; Feng, Jufu
2011-12-01
Fingerprint recognition is one of the most important technologies in biometric identification and has been wildly applied in commercial and forensic areas. Fingerprint classification, as the fundamental procedure in fingerprint recognition, can sharply decrease the quantity for fingerprint matching and improve the efficiency of fingerprint recognition. Most fingerprint classification algorithms are based on the number and position of singular points. Because the singular points detecting method only considers the local information commonly, the classification algorithms are sensitive to noise. In this paper, we propose a novel fingerprint classification algorithm combining the local and global information of fingerprint. Firstly we use local information to detect singular points and measure their quality considering orientation structure and image texture in adjacent areas. Furthermore the global orientation model is adopted to measure the reliability of singular points group. Finally the local quality and global reliability is weighted to classify fingerprint. Experiments demonstrate the accuracy and effectivity of our algorithm especially for the poor quality fingerprint images.
Design and Testing of a Tool for Evaluating the Quality of Diabetes Consumer-Information Web Sites
Steinwachs, Donald; Rubin, Haya R
2003-01-01
Background Most existing tools for measuring the quality of Internet health information focus almost exclusively on structural criteria or other proxies for quality information rather than evaluating actual accuracy and comprehensiveness. Objective This research sought to develop a new performance-measurement tool for evaluating the quality of Internet health information, test the validity and reliability of the tool, and assess the variability in diabetes Web site quality. Methods An objective, systematic tool was developed to evaluate Internet diabetes information based on a quality-of-care measurement framework. The principal investigator developed an abstraction tool and trained an external reviewer on its use. The tool included 7 structural measures and 34 performance measures created by using evidence-based practice guidelines and experts' judgments of accuracy and comprehensiveness. Results Substantial variation existed in all categories, with overall scores following a normal distribution and ranging from 15% to 95% (mean was 50% and median was 51%). Lin's concordance correlation coefficient to assess agreement between raters produced a rho of 0.761 (Pearson's r of 0.769), suggesting moderate to high agreement. The average agreement between raters for the performance measures was 0.80. Conclusions Diabetes Web site quality varies widely. Alpha testing of this new tool suggests that it could become a reliable and valid method for evaluating the quality of Internet health sites. Such an instrument could help lay people distinguish between beneficial and misleading information. PMID:14713658
Ferris, M; Cohen, S; Haberman, C; Javalkar, K; Massengill, S; Mahan, J D; Kim, S; Bickford, K; Cantu, G; Medeiros, M; Phillips, A; Ferris, M T; Hooper, S R
2015-01-01
The Self-Management and Transition to Adulthood with Rx=Treatment (STARx) Questionnaire was developed to collect information on self-management and health care transition (HCT) skills, via self-report, in a broad population of adolescents and young adults (AYAs) with chronic conditions. Over several iterations, the STARx questionnaire was created with AYA, family, and health provider input. The development and pilot testing of the STARx Questionnaire took place with the assistance of 1219 AYAs with different chronic health conditions, in multiple institutions and settings over three phases: item development, pilot testing, reliability and factor structuring. The three development phases resulted in a final version of the STARx Questionnaire. The exploratory factor analysis of the third version of the 18-item STARx identified six factors that accounted for about 65% of the variance: Medication management, Provider communication, Engagement during appointments, Disease knowledge, Adult health responsibilities, and Resource utilization. Reliability estimates revealed good internal consistency and temporal stability, with the alpha coefficient for the overall scale being .80. The STARx was developmentally sensitive, with older patients scoring significantly higher on nearly every factor than younger patients. The STARx Questionnaire is a reliable, self-report tool with adequate internal consistency, temporal stability, and a strong, multidimensional factor structure. It provides another assessment strategy to measure self-management and transition skills in AYAs with chronic conditions. Copyright © 2015 Elsevier Inc. All rights reserved.
1992-06-25
Zeolites are crystalline aluminosilicates that have complex framework structures. However, there are several features of zeolite crystals that make unequivocal structure determinations difficult. The acquisition of reliable structural information on zeolites is greatly facilitated by the availability of high-quality specimens. For structure determinations by conventional diffraction techniques, large single-crystal specimens are essential. Alternatively, structural determinations by powder profile refinement methods relax the constraints on crystal size, but still require materials with a high degree of crystalline perfection. Studies conducted at CAMMP (Center for Advanced Microgravity Materials Processing) have demonstrated that microgravity processing can produce larger crystal sizes and fewer structural defects relative to terrestrial crystal growth. Principal Investigator: Dr. Albert Sacco
NASA Technical Reports Server (NTRS)
1992-01-01
Zeolites are crystalline aluminosilicates that have complex framework structures. However, there are several features of zeolite crystals that make unequivocal structure determinations difficult. The acquisition of reliable structural information on zeolites is greatly facilitated by the availability of high-quality specimens. For structure determinations by conventional diffraction techniques, large single-crystal specimens are essential. Alternatively, structural determinations by powder profile refinement methods relax the constraints on crystal size, but still require materials with a high degree of crystalline perfection. Studies conducted at CAMMP (Center for Advanced Microgravity Materials Processing) have demonstrated that microgravity processing can produce larger crystal sizes and fewer structural defects relative to terrestrial crystal growth. Principal Investigator: Dr. Albert Sacco
Adaptive optical microscope for brain imaging in vivo
NASA Astrophysics Data System (ADS)
Wang, Kai
2017-04-01
The optical heterogeneity of biological tissue imposes a major limitation to acquire detailed structural and functional information deep in the biological specimens using conventional microscopes. To restore optimal imaging performance, we developed an adaptive optical microscope based on direct wavefront sensing technique. This microscope can reliably measure and correct biological samples induced aberration. We demonstrated its performance and application in structural and functional brain imaging in various animal models, including fruit fly, zebrafish and mouse.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-10
...] Electric Reliability Organization Proposal To Retire Requirements in Reliability Standards AGENCY: Federal... Reliability Standards identified by the North American Electric Reliability Corporation (NERC), the Commission-certified Electric Reliability Organization. FOR FURTHER INFORMATION CONTACT: Kevin Ryan (Legal Information...
DOE Office of Scientific and Technical Information (OSTI.GOV)
LaCommare, Kristina; Larsen, Peter; Eto, Joseph
Policymakers and regulatory agencies are expressing renewed interest in the reliability and resilience of the U.S. electric power system in large part due to growing recognition of the challenges posed by climate change, extreme weather events, and other emerging threats. Unfortunately, there has been little or no consolidated information in the public domain describing how public utility/service commission (PUC) staff evaluate the economics of proposed investments in the resilience of the power system. Having more consolidated information would give policymakers a better understanding of how different state regulatory entities across the U.S. make economic decisions pertaining to reliability/resiliency. To helpmore » address this, Lawrence Berkeley National Laboratory (LBNL) was tasked by the U.S. Department of Energy Office of Energy Policy and Systems Analysis (EPSA) to conduct an initial set of interviews with PUC staff to learn more about how proposed utility investments in reliability/resilience are being evaluated from an economics perspective. LBNL conducted structured interviews in late May-early June 2016 with staff from the following PUCs: Washington D.C. (DCPSC), Florida (FPSC), and California (CPUC).« less
Areia, Neide P; Major, Sofia; Relvas, Ana P
2017-10-01
The aim of this study was to validate the Portuguese version of the Family Inventory of Needs (FIN). The FIN aims to measure important family needs and their fulfilment by a healthcare team. This cross-sectional study involved a sample of 364 family members of cancer patients, recruited from three medical institutions and through online recruitment. Three instruments were used: a socio-demographic questionnaire, the FIN and the Brief Symptom Inventory - 18 (BSI-18). Construct validity and reliability were considered regarding the FIN's psychometric properties. The method used to determine construct validity was factor structure analysis (confirmatory factor analysis), inter-factor correlations (Spearman's rank correlation) and convergent validity (Spearman's rank correlation). To assess scale reliability, the FIN's internal consistency was evaluated (Cronbach's alpha coefficient). Descriptive and frequency statistics and tests to compare means were used to assess important needs and to what extent they were met. The four-factor structure of the FIN was confirmed. Thus, the FIN has four domains: Basic Information, Information on treatment and care, Support and Patient Comfort. Convergent validity with the BSI-18 was verified. Both subscales of the FIN and each domain exceeded the minimum reliability standard of 0.70. Family members also reported important needs that were not adequately met by healthcare professionals. The Portuguese version of the FIN seems to be a reliable and valid tool for identifying cancer patients' important family needs and to what extent these are met. Copyright © 2017 Elsevier Ltd. All rights reserved.
A reliability-based cost effective fail-safe design procedure
NASA Technical Reports Server (NTRS)
Hanagud, S.; Uppaluri, B.
1976-01-01
The authors have developed a methodology for cost-effective fatigue design of structures subject to random fatigue loading. A stochastic model for fatigue crack propagation under random loading has been discussed. Fracture mechanics is then used to estimate the parameters of the model and the residual strength of structures with cracks. The stochastic model and residual strength variations have been used to develop procedures for estimating the probability of failure and its changes with inspection frequency. This information on reliability is then used to construct an objective function in terms of either a total weight function or cost function. A procedure for selecting the design variables, subject to constraints, by optimizing the objective function has been illustrated by examples. In particular, optimum design of stiffened panel has been discussed.
DOT National Transportation Integrated Search
1984-10-01
The Transit Reliability Information Program (TRIP) is a government-initiated program to assist the transit industry in satisfying its need for transit reliability information. TRIP provides this assistance through the operation of a national data ban...
Training and quality assurance with the Structured Clinical Interview for DSM-IV (SCID-I/P).
Ventura, J; Liberman, R P; Green, M F; Shaner, A; Mintz, J
1998-06-15
Accuracy in psychiatric diagnosis is critical for evaluating the suitability of the subjects for entry into research protocols and for establishing comparability of findings across study sites. However, training programs in the use of diagnostic instruments for research projects are not well systematized. Furthermore, little information has been published on the maintenance of interrater reliability of diagnostic assessments. At the UCLA Research Center for Major Mental Illnesses, a Training and Quality Assurance Program for SCID interviewers was used to evaluate interrater reliability and diagnostic accuracy. Although clinically experienced interviewers achieved better interrater reliability and overall diagnostic accuracy than neophyte interviewers, both groups were able to achieve and maintain high levels of interrater reliability, diagnostic accuracy, and interviewer skill. At the first quality assurance check after training, there were no significant differences between experienced and neophyte interviewers in interrater reliability or diagnostic accuracy. Standardization of training and quality assurance procedures within and across research projects may make research findings from study sites more comparable.
E-Governance and Service Oriented Computing Architecture Model
NASA Astrophysics Data System (ADS)
Tejasvee, Sanjay; Sarangdevot, S. S.
2010-11-01
E-Governance is the effective application of information communication and technology (ICT) in the government processes to accomplish safe and reliable information lifecycle management. Lifecycle of the information involves various processes as capturing, preserving, manipulating and delivering information. E-Governance is meant to transform of governance in better manner to the citizens which is transparent, reliable, participatory, and accountable in point of view. The purpose of this paper is to attempt e-governance model, focus on the Service Oriented Computing Architecture (SOCA) that includes combination of information and services provided by the government, innovation, find out the way of optimal service delivery to citizens and implementation in transparent and liable practice. This paper also try to enhance focus on the E-government Service Manager as a essential or key factors service oriented and computing model that provides a dynamically extensible structural design in which all area or branch can bring in innovative services. The heart of this paper examine is an intangible model that enables E-government communication for trade and business, citizen and government and autonomous bodies.
Electrostatic and structural similarity of classical and non-classical lactam compounds
NASA Astrophysics Data System (ADS)
Coll, Miguel; Frau, Juan; Vilanova, Bartolomé; Donoso, Josefa; Muñoz, Francisco
2001-09-01
Various electrostatic and structural parameters for a series of classical and non-classical β-lactams were determined and compared in order to ascertain whether some specific β-lactams possess antibacterial or β-lactamase inhibitory properties. The electrostatic parameters obtained, based on the Distributed Multipole Analysis (DMA) of high-quality wavefunctions for the studied structures, suggest that some non-classical β-lactams effectively inhibit the action of β-lactamases. As shown in this work, such electrostatic parameters provide much more reliable information about the antibacterial and inhibitory properties of β-lactams than do structural parameters.
NASA Astrophysics Data System (ADS)
Kessler, Seth S.; Spearing, S. Mark
2002-07-01
Cost-effective and reliable damage detection is critical for the utilization of composite materials. This paper presents the conclusions of an experimental and analytical survey of candidate methods for in-situ damage detection in composite structures. Experimental results are presented for the application of modal analysis and Lamb wave techniques to quasi-isotropic graphite/epoxy test specimens containing representative damage. Piezoelectric patches were used as actuators and sensors for both sets of experiments. Modal analysis methods were reliable for detecting small amounts of global damage in a simple composite structure. By comparison, Lamb wave methods were sensitive to all types of local damage present between the sensor and actuator, provided useful information about damage presence and severity, and present the possibility of estimating damage type and location. Analogous experiments were also performed for more complex built-up structures. These techniques are suitable for structural health monitoring applications since they can be applied with low power conformable sensors and can provide useful information about the state of a structure during operation. Piezoelectric patches could also be used as multipurpose sensors to detect damage by a variety of methods such as modal analysis, Lamb wave, acoustic emission and strain based methods simultaneously, by altering driving frequencies and sampling rates. This paper present guidelines and recommendations drawn from this research to assist in the design of a structural health monitoring system for a vehicle. These systems will be an important component in future designs of air and spacecraft to increase the feasibility of their missions.
Markup of temporal information in electronic health records.
Hyun, Sookyung; Bakken, Suzanne; Johnson, Stephen B
2006-01-01
Temporal information plays a critical role in the understanding of clinical narrative (i.e., free text). We developed a representation for marking up temporal information in a narrative, consisting of five elements: 1) reference point, 2) direction, 3) number, 4) time unit, and 5) pattern. We identified 254 temporal expressions from 50 discharge summaries and represented them using our scheme. The overall inter-rater reliability among raters applying the representation model was 75 percent agreement. The model can contribute to temporal reasoning in computer systems for decision support, data mining, and process and outcomes analyses by providing structured temporal information.
Confidence in outcome estimates from systematic reviews used in informed consent.
Fritz, Robert; Bauer, Janet G; Spackman, Sue S; Bains, Amanjyot K; Jetton-Rangel, Jeanette
2016-12-01
Evidence-based dentistry now guides informed consent in which clinicians are obliged to provide patients with the most current, best evidence, or best estimates of outcomes, of regimens, therapies, treatments, procedures, materials, and equipment or devices when developing personal oral health care, treatment plans. Yet, clinicians require that the estimates provided from systematic reviews be verified to their validity, reliability, and contextualized as to performance competency so that clinicians may have confidence in explaining outcomes to patients in clinical practice. The purpose of this paper was to describe types of informed estimates from which clinicians may have confidence in their capacity to assist patients in competent decision-making, one of the most important concepts of informed consent. Using systematic review methodology, researchers provide clinicians with valid best estimates of outcomes regarding a subject of interest from best evidence. Best evidence is verified through critical appraisals using acceptable sampling methodology either by scoring instruments (Timmer analysis) or checklist (grade), a Cochrane Collaboration standard that allows transparency in open reviews. These valid best estimates are then tested for reliability using large databases. Finally, valid and reliable best estimates are assessed for meaning using quantification of margins and uncertainties. Through manufacturer and researcher specifications, quantification of margins and uncertainties develops a performance competency continuum by which valid, reliable best estimates may be contextualized for their performance competency: at a lowest margin performance competency (structural failure), high margin performance competency (estimated true value of success), or clinically determined critical values (clinical failure). Informed consent may be achieved when clinicians are confident of their ability to provide useful and accurate best estimates of outcomes regarding regimens, therapies, treatments, and equipment or devices to patients in their clinical practices and when developing personal, oral health care, treatment plans. Copyright © 2016 Elsevier Inc. All rights reserved.
Crossley, James G M
2015-01-01
Nurse appraisal is well established in the Western world because of its obvious educational advantages. Appraisal works best with many sources of information on performance. Multisource feedback (MSF) is widely used in business and in other clinical disciplines to provide such information. It has also been incorporated into nursing appraisals, but, so far, none of the instruments in use for nurses has been validated. We set out to develop an instrument aligned with the UK Knowledge and Skills Framework (KSF) and to evaluate its reliability and feasibility across a wide hospital-based nursing population. The KSF framework provided a content template. Focus groups developed an instrument based on consensus. The instrument was administered to all the nursing staff in 2 large NHS hospitals forming a single trust in London, England. We used generalizability analysis to estimate reliability, response rates and unstructured interviews to evaluate feasibility, and factor structure and correlation studies to evaluate validity. On a voluntary basis the response rate was moderate (60%). A failure to engage with information technology and employment-related concerns were commonly cited as reasons for not responding. In this population, 11 responses provided a profile with sufficient reliability to inform appraisal (G = 0.7). Performance on the instrument was closely and significantly correlated with performance on a KSF questionnaire. This is the first contemporary psychometric evaluation of an MSF instrument for nurses. MSF appears to be as valid and reliable as an assessment method to inform appraisal in nurses as it is in other health professional groups. © 2015 The Alliance for Continuing Education in the Health Professions, the Society for Academic Continuing Medical Education, and the Council on Continuing Medical Education, Association for Hospital Medical Education.
NASA Astrophysics Data System (ADS)
Kuznetsov, P. A.; Kovalev, I. V.; Losev, V. V.; Kalinin, A. O.; Murygin, A. V.
2016-04-01
The article discusses the reliability of automated control systems. Analyzes the approach to the classification systems for health States. This approach can be as traditional binary approach, operating with the concept of "serviceability", and other variants of estimation of the system state. This article provides one such option, providing selective evaluation of components for the reliability of the entire system. Introduced description of various automatic control systems and their elements from the point of view of health and risk, mathematical method of determining the transition object from state to state, they differ from each other in the implementation of the objective function. Explores the interplay of elements in different States, the aggregate state of the elements connected in series or in parallel. Are the tables of various logic States and the principles of their calculation in series and parallel connection. Through simulation the proposed approach is illustrated by finding the probability of getting into the system state data in parallel and serially connected elements, with their different probabilities of moving from state to state. In general, the materials of article will be useful for analyzing of the reliability the automated control systems and engineering of the highly-reliable systems. Thus, this mechanism to determine the State of the system provides more detailed information about it and allows a selective approach to the reliability of the system as a whole. Detailed results when assessing the reliability of the automated control systems allows the engineer to make an informed decision when designing means of improving reliability.
DOT National Transportation Integrated Search
1981-08-01
The Transit Reliability Information Program (TRIP) is a government-initiated program to assist the transit industry in satisfying its need for transit reliability information. TRIP provides this assistance through the operation of a national Data Ban...
NASA Astrophysics Data System (ADS)
Andriushin, A. V.; Dolbikova, N. S.; Kiet, S. V.; Merzlikina, E. I.; Nikitina, I. S.
2017-11-01
The reliability of the main equipment of any power station depends on the correct water chemistry. In order to provide it, it is necessary to monitor the heat carrier quality, which, in its turn, is provided by the chemical monitoring system. Thus, the monitoring system reliability plays an important part in providing reliability of the main equipment. The monitoring system reliability is determined by the reliability and structure of its hardware and software consisting of sensors, controllers, HMI and so on [1,2]. Workers of a power plant dealing with the measuring equipment must be informed promptly about any breakdowns in the monitoring system, in this case they are able to remove the fault quickly. A computer consultant system for personnel maintaining the sensors and other chemical monitoring equipment can help to notice faults quickly and identify their possible causes. Some technical solutions for such a system are considered in the present paper. The experimental results were obtained on the laboratory and experimental workbench representing a physical model of a part of the chemical monitoring system.
E-MSD: an integrated data resource for bioinformatics
Velankar, S.; McNeil, P.; Mittard-Runte, V.; Suarez, A.; Barrell, D.; Apweiler, R.; Henrick, K.
2005-01-01
The Macromolecular Structure Database (MSD) group (http://www.ebi.ac.uk/msd/) continues to enhance the quality and consistency of macromolecular structure data in the worldwide Protein Data Bank (wwPDB) and to work towards the integration of various bioinformatics data resources. One of the major obstacles to the improved integration of structural databases such as MSD and sequence databases like UniProt is the absence of up to date and well-maintained mapping between corresponding entries. We have worked closely with the UniProt group at the EBI to clean up the taxonomy and sequence cross-reference information in the MSD and UniProt databases. This information is vital for the reliable integration of the sequence family databases such as Pfam and Interpro with the structure-oriented databases of SCOP and CATH. This information has been made available to the eFamily group (http://www.efamily.org.uk/) and now forms the basis of the regular interchange of information between the member databases (MSD, UniProt, Pfam, Interpro, SCOP and CATH). This exchange of annotation information has enriched the structural information in the MSD database with annotation from wider sequence-oriented resources. This work was carried out under the ‘Structure Integration with Function, Taxonomy and Sequences (SIFTS)’ initiative (http://www.ebi.ac.uk/msd-srv/docs/sifts) in the MSD group. PMID:15608192
77 FR 39691 - Commission Information Collection Activities (FERC-725); Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-05
... information collection FERC-725, Certification of Electric Reliability Organization; Procedures for Electric Reliability Standards, to the Office of Management and Budget (OMB) for review of the information collection..., Certification of Electric Reliability Organization; Procedures for Electric Reliability Standards. OMB Control...
Reliability and risk assessment of structures
NASA Technical Reports Server (NTRS)
Chamis, C. C.
1991-01-01
Development of reliability and risk assessment of structural components and structures is a major activity at Lewis Research Center. It consists of five program elements: (1) probabilistic loads; (2) probabilistic finite element analysis; (3) probabilistic material behavior; (4) assessment of reliability and risk; and (5) probabilistic structural performance evaluation. Recent progress includes: (1) the evaluation of the various uncertainties in terms of cumulative distribution functions for various structural response variables based on known or assumed uncertainties in primitive structural variables; (2) evaluation of the failure probability; (3) reliability and risk-cost assessment; and (4) an outline of an emerging approach for eventual certification of man-rated structures by computational methods. Collectively, the results demonstrate that the structural durability/reliability of man-rated structural components and structures can be effectively evaluated by using formal probabilistic methods.
ERIC Educational Resources Information Center
Honey, Emma; McConachie, Helen; Turner, Michelle; Rodgers, Jacqui
2012-01-01
The repetitive behaviour questionnaire (RBQ) (Turner, 1995) is one of the three most commonly used interview/questionnaire measures of repetitive behaviour (Honey et al., in preparation). Despite this there is a scarcity of information concerning its structure, reliability and validity. The psychometric properties of the RBQ were examined when…
On the magnetic circular dichroism of benzene. A density-functional study
NASA Astrophysics Data System (ADS)
Kaminský, Jakub; Kříž, Jan; Bouř, Petr
2017-04-01
Spectroscopy of magnetic circular dichroism (MCD) provides enhanced information on molecular structure and a more reliable assignment of spectral bands than absorption alone. Theoretical modeling can significantly enhance the information obtained from experimental spectra. In the present study, the time dependent density functional theory is employed to model the lowest-energy benzene transitions, in particular to investigate the role of the Rydberg states and vibrational interference in spectral intensities. The effect of solvent is explored on model benzene-methane clusters. For the lowest-energy excitation, the vibrational sub-structure of absorption and MCD spectra is modeled within the harmonic approximation, providing a very good agreement with the experiment. The simulations demonstrate that the Rydberg states have a much stronger effect on the MCD intensities than on the absorption, and a very diffuse basis set must be used to obtain reliable results. The modeling also indicates that the Rydberg-like states and associated transitions may persist in solutions. Continuum-like solvent models are thus not suitable for their modeling; solvent-solute clusters appear to be more appropriate, providing they are large enough.
da Silva, Wanderson Roberto; Dias, Juliana Chioda Ribeiro; Maroco, João; Campos, Juliana Alvares Duarte Bonini
2014-09-01
This study aimed at evaluating the validity, reliability, and factorial invariance of the complete (34-item) and shortened (8-item and 16-item) versions of the Body Shape Questionnaire (BSQ) when applied to Brazilian university students. A total of 739 female students with a mean age of 20.44 (standard deviation=2.45) years participated. Confirmatory factor analysis was conducted to verify the degree to which the one-factor structure satisfies the proposal for the BSQ's expected structure. Two items of the 34-item version were excluded because they had factor weights (λ)<40. All models had adequate convergent validity (average variance extracted=.43-.58; composite reliability=.85-.97) and internal consistency (α=.85-.97). The 8-item B version was considered the best shortened BSQ version (Akaike information criterion=84.07, Bayes information criterion=157.75, Browne-Cudeck criterion=84.46), with strong invariance for independent samples (Δχ(2)λ(7)=5.06, Δχ(2)Cov(8)=5.11, Δχ(2)Res(16)=19.30). Copyright © 2014 Elsevier Ltd. All rights reserved.
Profiling defect depth in composite materials using thermal imaging NDE
NASA Astrophysics Data System (ADS)
Obeidat, Omar; Yu, Qiuye; Han, Xiaoyan
2018-04-01
Sonic Infrared (IR) NDE, is a relatively new NDE technology; it has been demonstrated as a reliable and sensitive method to detect defects. SIR uses ultrasonic excitation with IR imaging to detect defects and flaws in the structures being inspected. An IR camera captures infrared radiation from the target for a period of time covering the ultrasound pulse. This period of time may be much longer than the pulse depending on the defect depth and the thermal properties of the materials. With the increasing deployment of composites in modern aerospace and automobile structures, fast, wide-area and reliable NDE methods are necessary. Impact damage is one of the major concerns in modern composites. Damage can occur at a certain depth without any visual indication on the surface. Defect depth information can influence maintenance decisions. Depth profiling relies on the time delays in the captured image sequence. We'll present our work on the defect depth profiling by using the temporal information of IR images. An analytical model is introduced to describe heat diffusion from subsurface defects in composite materials. Depth profiling using peak time is introduced as well.
1982-01-01
different bits of information to fly his plane, etc.) 35. Analyzing information (interpreting financial reports, determining why an automobile engine...involvin- hand and arm movements, as might be used in repairing automobiles , packaging products, etc.) I48. liand-arm steadiness (steady hand and arm...devices (pianos, typewriters, adding Rating Scale machines, etc.) 0 None 100. Highway or rail vehicles ( automobiles , trucks, 1 Very limited buses, trains
Automating annotation of information-giving for analysis of clinical conversation.
Mayfield, Elijah; Laws, M Barton; Wilson, Ira B; Penstein Rosé, Carolyn
2014-02-01
Coding of clinical communication for fine-grained features such as speech acts has produced a substantial literature. However, annotation by humans is laborious and expensive, limiting application of these methods. We aimed to show that through machine learning, computers could code certain categories of speech acts with sufficient reliability to make useful distinctions among clinical encounters. The data were transcripts of 415 routine outpatient visits of HIV patients which had previously been coded for speech acts using the Generalized Medical Interaction Analysis System (GMIAS); 50 had also been coded for larger scale features using the Comprehensive Analysis of the Structure of Encounters System (CASES). We aggregated selected speech acts into information-giving and requesting, then trained the machine to automatically annotate using logistic regression classification. We evaluated reliability by per-speech act accuracy. We used multiple regression to predict patient reports of communication quality from post-visit surveys using the patient and provider information-giving to information-requesting ratio (briefly, information-giving ratio) and patient gender. Automated coding produces moderate reliability with human coding (accuracy 71.2%, κ=0.57), with high correlation between machine and human prediction of the information-giving ratio (r=0.96). The regression significantly predicted four of five patient-reported measures of communication quality (r=0.263-0.344). The information-giving ratio is a useful and intuitive measure for predicting patient perception of provider-patient communication quality. These predictions can be made with automated annotation, which is a practical option for studying large collections of clinical encounters with objectivity, consistency, and low cost, providing greater opportunity for training and reflection for care providers.
Nearest-neighbor guided evaluation of data reliability and its applications.
Boongoen, Tossapon; Shen, Qiang
2010-12-01
The intuition of data reliability has recently been incorporated into the main stream of research on ordered weighted averaging (OWA) operators. Instead of relying on human-guided variables, the aggregation behavior is determined in accordance with the underlying characteristics of the data being aggregated. Data-oriented operators such as the dependent OWA (DOWA) utilize centralized data structures to generate reliable weights, however. Despite their simplicity, the approach taken by these operators neglects entirely any local data structure that represents a strong agreement or consensus. To address this issue, the cluster-based OWA (Clus-DOWA) operator has been proposed. It employs a cluster-based reliability measure that is effective to differentiate the accountability of different input arguments. Yet, its actual application is constrained by the high computational requirement. This paper presents a more efficient nearest-neighbor-based reliability assessment for which an expensive clustering process is not required. The proposed measure can be perceived as a stress function, from which the OWA weights and associated decision-support explanations can be generated. To illustrate the potential of this measure, it is applied to both the problem of information aggregation for alias detection and the problem of unsupervised feature selection (in which unreliable features are excluded from an actual learning process). Experimental results demonstrate that these techniques usually outperform their conventional state-of-the-art counterparts.
Paige, Samantha R; Krieger, Janice L; Stellefson, Michael; Alber, Julia M
2017-02-01
Chronic disease patients are affected by low computer and health literacy, which negatively affects their ability to benefit from access to online health information. To estimate reliability and confirm model specifications for eHealth Literacy Scale (eHEALS) scores among chronic disease patients using Classical Test (CTT) and Item Response Theory techniques. A stratified sample of Black/African American (N=341) and Caucasian (N=343) adults with chronic disease completed an online survey including the eHEALS. Item discrimination was explored using bi-variate correlations and Cronbach's alpha for internal consistency. A categorical confirmatory factor analysis tested a one-factor structure of eHEALS scores. Item characteristic curves, in-fit/outfit statistics, omega coefficient, and item reliability and separation estimates were computed. A 1-factor structure of eHEALS was confirmed by statistically significant standardized item loadings, acceptable model fit indices (CFI/TLI>0.90), and 70% variance explained by the model. Item response categories increased with higher theta levels, and there was evidence of acceptable reliability (ω=0.94; item reliability=89; item separation=8.54). eHEALS scores are a valid and reliable measure of self-reported eHealth literacy among Internet-using chronic disease patients. Providers can use eHEALS to help identify patients' eHealth literacy skills. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Chemical computing with reaction-diffusion processes.
Gorecki, J; Gizynski, K; Guzowski, J; Gorecka, J N; Garstecki, P; Gruenert, G; Dittrich, P
2015-07-28
Chemical reactions are responsible for information processing in living organisms. It is believed that the basic features of biological computing activity are reflected by a reaction-diffusion medium. We illustrate the ideas of chemical information processing considering the Belousov-Zhabotinsky (BZ) reaction and its photosensitive variant. The computational universality of information processing is demonstrated. For different methods of information coding constructions of the simplest signal processing devices are described. The function performed by a particular device is determined by the geometrical structure of oscillatory (or of excitable) and non-excitable regions of the medium. In a living organism, the brain is created as a self-grown structure of interacting nonlinear elements and reaches its functionality as the result of learning. We discuss whether such a strategy can be adopted for generation of chemical information processing devices. Recent studies have shown that lipid-covered droplets containing solution of reagents of BZ reaction can be transported by a flowing oil. Therefore, structures of droplets can be spontaneously formed at specific non-equilibrium conditions, for example forced by flows in a microfluidic reactor. We describe how to introduce information to a droplet structure, track the information flow inside it and optimize medium evolution to achieve the maximum reliability. Applications of droplet structures for classification tasks are discussed. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
A Delay-Aware and Reliable Data Aggregation for Cyber-Physical Sensing
Zhang, Jinhuan; Long, Jun; Zhang, Chengyuan; Zhao, Guihu
2017-01-01
Physical information sensed by various sensors in a cyber-physical system should be collected for further operation. In many applications, data aggregation should take reliability and delay into consideration. To address these problems, a novel Tiered Structure Routing-based Delay-Aware and Reliable Data Aggregation scheme named TSR-DARDA for spherical physical objects is proposed. By dividing the spherical network constructed by dispersed sensor nodes into circular tiers with specifically designed widths and cells, TSTR-DARDA tries to enable as many nodes as possible to transmit data simultaneously. In order to ensure transmission reliability, lost packets are retransmitted. Moreover, to minimize the latency while maintaining reliability for data collection, in-network aggregation and broadcast techniques are adopted to deal with the transmission between data collecting nodes in the outer layer and their parent data collecting nodes in the inner layer. Thus, the optimization problem is transformed to minimize the delay under reliability constraints by controlling the system parameters. To demonstrate the effectiveness of the proposed scheme, we have conducted extensive theoretical analysis and comparisons to evaluate the performance of TSR-DARDA. The analysis and simulations show that TSR-DARDA leads to lower delay with reliability satisfaction. PMID:28218668
Functional classification of protein structures by local structure matching in graph representation.
Mills, Caitlyn L; Garg, Rohan; Lee, Joslynn S; Tian, Liang; Suciu, Alexandru; Cooperman, Gene; Beuning, Penny J; Ondrechen, Mary Jo
2018-03-31
As a result of high-throughput protein structure initiatives, over 14,400 protein structures have been solved by structural genomics (SG) centers and participating research groups. While the totality of SG data represents a tremendous contribution to genomics and structural biology, reliable functional information for these proteins is generally lacking. Better functional predictions for SG proteins will add substantial value to the structural information already obtained. Our method described herein, Graph Representation of Active Sites for Prediction of Function (GRASP-Func), predicts quickly and accurately the biochemical function of proteins by representing residues at the predicted local active site as graphs rather than in Cartesian coordinates. We compare the GRASP-Func method to our previously reported method, structurally aligned local sites of activity (SALSA), using the ribulose phosphate binding barrel (RPBB), 6-hairpin glycosidase (6-HG), and Concanavalin A-like Lectins/Glucanase (CAL/G) superfamilies as test cases. In each of the superfamilies, SALSA and the much faster method GRASP-Func yield similar correct classification of previously characterized proteins, providing a validated benchmark for the new method. In addition, we analyzed SG proteins using our SALSA and GRASP-Func methods to predict function. Forty-one SG proteins in the RPBB superfamily, nine SG proteins in the 6-HG superfamily, and one SG protein in the CAL/G superfamily were successfully classified into one of the functional families in their respective superfamily by both methods. This improved, faster, validated computational method can yield more reliable predictions of function that can be used for a wide variety of applications by the community. © 2018 The Authors Protein Science published by Wiley Periodicals, Inc. on behalf of The Protein Society.
Great apes are sensitive to prior reliability of an informant in a gaze following task.
Schmid, Benjamin; Karg, Katja; Perner, Josef; Tomasello, Michael
2017-01-01
Social animals frequently rely on information from other individuals. This can be costly in case the other individual is mistaken or even deceptive. Human infants below 4 years of age show proficiency in their reliance on differently reliable informants. They can infer the reliability of an informant from few interactions and use that assessment in later interactions with the same informant in a different context. To explore whether great apes share that ability, in our study we confronted great apes with a reliable or unreliable informant in an object choice task, to see whether that would in a subsequent task affect their gaze following behaviour in response to the same informant. In our study, prior reliability of the informant and habituation during the gaze following task affected both great apes' automatic gaze following response and their more deliberate response of gaze following behind barriers. As habituation is very context specific, it is unlikely that habituation in the reliability task affected the gaze following task. Rather it seems that apes employ a reliability tracking strategy that results in a general avoidance of additional information from an unreliable informant.
Sources of medicine information and their reliability evaluated by medicine users.
Närhi, Ulla
2007-12-01
To study the medicine users' sources of medicine information and the perceived reliability of these sources in different age groups. A computer-aided telephone interview (CATI) to Finnish consumers (n = 1,004). Those respondents (n = 714) who reported using any prescription or self-medication medicines more than once a month were included in the study. The respondents were interviewed about their use of sources of medicine information during the previous 6 months. The reliability of sources in different age groups was estimated using a 4-point scale: very reliable, somewhat reliable, somewhat unreliable and very unreliable. The respondents also had the option of being unable to make an appraisal. A proportion of respondents reporting using the source, number of mentioned sources and their reliability evaluated by respondents. About half of the respondents in each age group mentioned two to four sources. The most common sources of information were Patient Information Leaflets (PILs) (74%), doctors (68%) and pharmacists (60%). Next came television (40%), newspapers and magazines (40%), drug advertisements (32%), nurses (28%), drug information leaflets (27%), relatives and friends (24%), medicine guides and books (22%) and the Internet (20%). There was a significant difference between age groups in reporting the Internet as a source of medicine information (15-34-year-old respondents reported the greatest Internet use). The three most reliable sources in every age group were reported to be PILs, doctors and pharmacists. Nurses, drug regulatory authorities, drug information leaflets and medicine guides and books were considered next most reliable. Relatives and friends, television, newspapers and magazines were considered the least reliable. The respondents were most uncertain about the reliability of the Internet, patient organisations and telephone services. There was a significant difference between age groups in evaluating the reliability of telephone services (15-34-year-olds found them more reliable). Medicine users reported receiving medicine information from many sources. The most commonly used sources were perceived as the most reliable, but their reliability did not seem to depend on age. The counsellors should take into account that patients have many sources of medicine information, with varying validity.
New methodologies for multi-scale time-variant reliability analysis of complex lifeline networks
NASA Astrophysics Data System (ADS)
Kurtz, Nolan Scot
The cost of maintaining existing civil infrastructure is enormous. Since the livelihood of the public depends on such infrastructure, its state must be managed appropriately using quantitative approaches. Practitioners must consider not only which components are most fragile to hazard, e.g. seismicity, storm surge, hurricane winds, etc., but also how they participate on a network level using network analysis. Focusing on particularly damaged components does not necessarily increase network functionality, which is most important to the people that depend on such infrastructure. Several network analyses, e.g. S-RDA, LP-bounds, and crude-MCS, and performance metrics, e.g. disconnection bounds and component importance, are available for such purposes. Since these networks are existing, the time state is also important. If networks are close to chloride sources, deterioration may be a major issue. Information from field inspections may also have large impacts on quantitative models. To address such issues, hazard risk analysis methodologies for deteriorating networks subjected to seismicity, i.e. earthquakes, have been created from analytics. A bridge component model has been constructed for these methodologies. The bridge fragilities, which were constructed from data, required a deeper level of analysis as these were relevant for specific structures. Furthermore, chloride-induced deterioration network effects were investigated. Depending on how mathematical models incorporate new information, many approaches are available, such as Bayesian model updating. To make such procedures more flexible, an adaptive importance sampling scheme was created for structural reliability problems. Additionally, such a method handles many kinds of system and component problems with singular or multiple important regions of the limit state function. These and previously developed analysis methodologies were found to be strongly sensitive to the network size. Special network topologies may be more or less computationally difficult, while the resolution of the network also has large affects. To take advantage of some types of topologies, network hierarchical structures with super-link representation have been used in the literature to increase the computational efficiency by analyzing smaller, densely connected networks; however, such structures were based on user input and subjective at times. To address this, algorithms must be automated and reliable. These hierarchical structures may indicate the structure of the network itself. This risk analysis methodology has been expanded to larger networks using such automated hierarchical structures. Component importance is the most important objective from such network analysis; however, this may only provide the information of which bridges to inspect/repair earliest and little else. High correlations influence such component importance measures in a negative manner. Additionally, a regional approach is not appropriately modelled. To investigate a more regional view, group importance measures based on hierarchical structures have been created. Such structures may also be used to create regional inspection/repair approaches. Using these analytical, quantitative risk approaches, the next generation of decision makers may make both component and regional-based optimal decisions using information from both network function and further effects of infrastructure deterioration.
Bonati, Laura; Corrada, Dario; Tagliabue, Sara Giani; Motta, Stefano
2017-02-01
Molecular modeling has given important contributions to elucidation of the main stages in the AhR signal transduction pathway. Despite the lack of experimentally determined structures of the AhR functional domains, information derived from homologous systems has been exploited for modeling their structure and interactions. Homology models of the AhR PASB domain have provided information on the binding cavity and contributed to elucidate species-specific differences in ligand binding. Molecular Docking simulations of the ligand binding process have given insights into differences in binding of diverse agonists, antagonists, and selective AhR modulators, and their application to virtual screening of large databases of compounds have allowed identification of novel AhR ligands. Recently available structural information on protein-protein and protein-DNA complexes of other bHLH-PAS systems has opened the way for modeling the AhR:ARNT dimer structure and investigating the mechanisms of AhR transformation and DNA binding. Future research directions should include simulation of the protein dynamics to obtain a more reliable description of intermolecular interactions involved in signal transmission.
Suen, Yi-Nam; Cerin, Ester; Mellecker, Robin R
2014-07-18
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. 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. 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 showed acceptable levels of internal consistency (Cronbach's α >0.70). A reliable scale examining PA-related informal social control relevant to Chinese parents/caregivers of pre-schoolers living in Hong Kong was developed. Further studies should examine the factorial validity of the scale, its associations with Chinese children's PA and its appropriateness for other populations of parents of young children.
Inspection of Piezoceramic Transducers Used for Structural Health Monitoring
Mueller, Inka; Fritzen, Claus-Peter
2017-01-01
The use of piezoelectric wafer active sensors (PWAS) for structural health monitoring (SHM) purposes is state of the art for acousto-ultrasonic-based methods. For system reliability, detailed information about the PWAS itself is necessary. This paper gives an overview on frequent PWAS faults and presents the effects of these faults on the wave propagation, used for active acousto-ultrasonics-based SHM. The analysis of the wave field is based on velocity measurements using a laser Doppler vibrometer (LDV). New and established methods of PWAS inspection are explained in detail, listing advantages and disadvantages. The electro-mechanical impedance spectrum as basis for these methods is discussed for different sensor faults. This way this contribution focuses on a detailed analysis of PWAS and the need of their inspection for an increased reliability of SHM systems. PMID:28772431
NASA Technical Reports Server (NTRS)
Cruse, T. A.
1987-01-01
The objective is the development of several modular structural analysis packages capable of predicting the probabilistic response distribution for key structural variables such as maximum stress, natural frequencies, transient response, etc. The structural analysis packages are to include stochastic modeling of loads, material properties, geometry (tolerances), and boundary conditions. The solution is to be in terms of the cumulative probability of exceedance distribution (CDF) and confidence bounds. Two methods of probability modeling are to be included as well as three types of structural models - probabilistic finite-element method (PFEM); probabilistic approximate analysis methods (PAAM); and probabilistic boundary element methods (PBEM). The purpose in doing probabilistic structural analysis is to provide the designer with a more realistic ability to assess the importance of uncertainty in the response of a high performance structure. Probabilistic Structural Analysis Method (PSAM) tools will estimate structural safety and reliability, while providing the engineer with information on the confidence that should be given to the predicted behavior. Perhaps most critically, the PSAM results will directly provide information on the sensitivity of the design response to those variables which are seen to be uncertain.
NASA Technical Reports Server (NTRS)
Cruse, T. A.; Burnside, O. H.; Wu, Y.-T.; Polch, E. Z.; Dias, J. B.
1988-01-01
The objective is the development of several modular structural analysis packages capable of predicting the probabilistic response distribution for key structural variables such as maximum stress, natural frequencies, transient response, etc. The structural analysis packages are to include stochastic modeling of loads, material properties, geometry (tolerances), and boundary conditions. The solution is to be in terms of the cumulative probability of exceedance distribution (CDF) and confidence bounds. Two methods of probability modeling are to be included as well as three types of structural models - probabilistic finite-element method (PFEM); probabilistic approximate analysis methods (PAAM); and probabilistic boundary element methods (PBEM). The purpose in doing probabilistic structural analysis is to provide the designer with a more realistic ability to assess the importance of uncertainty in the response of a high performance structure. Probabilistic Structural Analysis Method (PSAM) tools will estimate structural safety and reliability, while providing the engineer with information on the confidence that should be given to the predicted behavior. Perhaps most critically, the PSAM results will directly provide information on the sensitivity of the design response to those variables which are seen to be uncertain.
Bruckert, G; Vivien, D; Docagne, F; Roussel, B D
2016-04-01
Reverse transcription quantitative-polymerase chain reaction (RT-qPCR) has become a routine method in many laboratories. Normalization of data from experimental conditions is critical for data processing and is usually achieved by the use of a single reference gene. Nevertheless, as pointed by the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines, several reference genes should be used for reliable normalization. Ageing is a physiological process that results in a decline of many expressed genes. Reliable normalization of RT-qPCR data becomes crucial when studying ageing. Here, we propose a RT-qPCR study from four mouse brain regions (cortex, hippocampus, striatum and cerebellum) at different ages (from 8 weeks to 22 months) in which we studied the expression of nine commonly used reference genes. With the use of two different algorithms, we found that all brain structures need at least two genes for a good normalization step. We propose specific pairs of gene for efficient data normalization in the four brain regions studied. These results underline the importance of reliable reference genes for specific brain regions in ageing.
Gradient-based reliability maps for ACM-based segmentation of hippocampus.
Zarpalas, Dimitrios; Gkontra, Polyxeni; Daras, Petros; Maglaveras, Nicos
2014-04-01
Automatic segmentation of deep brain structures, such as the hippocampus (HC), in MR images has attracted considerable scientific attention due to the widespread use of MRI and to the principal role of some structures in various mental disorders. In this literature, there exists a substantial amount of work relying on deformable models incorporating prior knowledge about structures' anatomy and shape information. However, shape priors capture global shape characteristics and thus fail to model boundaries of varying properties; HC boundaries present rich, poor, and missing gradient regions. On top of that, shape prior knowledge is blended with image information in the evolution process, through global weighting of the two terms, again neglecting the spatially varying boundary properties, causing segmentation faults. An innovative method is hereby presented that aims to achieve highly accurate HC segmentation in MR images, based on the modeling of boundary properties at each anatomical location and the inclusion of appropriate image information for each of those, within an active contour model framework. Hence, blending of image information and prior knowledge is based on a local weighting map, which mixes gradient information, regional and whole brain statistical information with a multi-atlas-based spatial distribution map of the structure's labels. Experimental results on three different datasets demonstrate the efficacy and accuracy of the proposed method.
Global remote sensing of water-chlorophyll ratio in terrestrial plant leaves.
Kushida, Keiji
2012-10-01
I evaluated the use of global remote sensing techniques for estimating plant leaf chlorophyll a + b (C(ab); μg cm(-2)) and water (C(w); mg cm(-2)) concentrations as well as the ratio of C(w)/C(ab) with the PROSAIL model under possible distributions for leaf and soil spectra, leaf area index (LAI), canopy geometric structure, and leaf size. First, I estimated LAI from the normalized difference vegetation index. I found that, at LAI values <2, C(ab), C(w), and C(w)/C(ab) could not be reliably estimated. At LAI values >2, C(ab) and C(w) could be estimated for only restricted ranges of the canopy structure; however, the ratio of C(w)/C(ab) could be reliably estimated for a variety of possible canopy structures with coefficients of determination (R(2)) ranging from 0.56 to 0.90. The remote estimation of the C(w)/C(ab) ratio from satellites offers information on plant condition at a global scale.
Shen, Yang; Bax, Ad
2015-01-01
Summary Chemical shifts are obtained at the first stage of any protein structural study by NMR spectroscopy. Chemical shifts are known to be impacted by a wide range of structural factors and the artificial neural network based TALOS-N program has been trained to extract backbone and sidechain torsion angles from 1H, 15N and 13C shifts. The program is quite robust, and typically yields backbone torsion angles for more than 90% of the residues, and sidechain χ1 rotamer information for about half of these, in addition to reliably predicting secondary structure. The use of TALOS-N is illustrated for the protein DinI, and torsion angles obtained by TALOS-N analysis from the measured chemical shifts of its backbone and 13Cβ nuclei are compared to those seen in a prior, experimentally determined structure. The program is also particularly useful for generating torsion angle restraints, which then can be used during standard NMR protein structure calculations. PMID:25502373
Jeong, Chan-Seok; Kim, Dongsup
2016-02-24
Elucidating the cooperative mechanism of interconnected residues is an important component toward understanding the biological function of a protein. Coevolution analysis has been developed to model the coevolutionary information reflecting structural and functional constraints. Recently, several methods have been developed based on a probabilistic graphical model called the Markov random field (MRF), which have led to significant improvements for coevolution analysis; however, thus far, the performance of these models has mainly been assessed by focusing on the aspect of protein structure. In this study, we built an MRF model whose graphical topology is determined by the residue proximity in the protein structure, and derived a novel positional coevolution estimate utilizing the node weight of the MRF model. This structure-based MRF method was evaluated for three data sets, each of which annotates catalytic site, allosteric site, and comprehensively determined functional site information. We demonstrate that the structure-based MRF architecture can encode the evolutionary information associated with biological function. Furthermore, we show that the node weight can more accurately represent positional coevolution information compared to the edge weight. Lastly, we demonstrate that the structure-based MRF model can be reliably built with only a few aligned sequences in linear time. The results show that adoption of a structure-based architecture could be an acceptable approximation for coevolution modeling with efficient computation complexity.
Application of the Probabilistic Dynamic Synthesis Method to the Analysis of a Realistic Structure
NASA Technical Reports Server (NTRS)
Brown, Andrew M.; Ferri, Aldo A.
1998-01-01
The Probabilistic Dynamic Synthesis method is a new technique for obtaining the statistics of a desired response engineering quantity for a structure with non-deterministic parameters. The method uses measured data from modal testing of the structure as the input random variables, rather than more "primitive" quantities like geometry or material variation. This modal information is much more comprehensive and easily measured than the "primitive" information. The probabilistic analysis is carried out using either response surface reliability methods or Monte Carlo simulation. A previous work verified the feasibility of the PDS method on a simple seven degree-of-freedom spring-mass system. In this paper, extensive issues involved with applying the method to a realistic three-substructure system are examined, and free and forced response analyses are performed. The results from using the method are promising, especially when the lack of alternatives for obtaining quantitative output for probabilistic structures is considered.
Application of the Probabilistic Dynamic Synthesis Method to Realistic Structures
NASA Technical Reports Server (NTRS)
Brown, Andrew M.; Ferri, Aldo A.
1998-01-01
The Probabilistic Dynamic Synthesis method is a technique for obtaining the statistics of a desired response engineering quantity for a structure with non-deterministic parameters. The method uses measured data from modal testing of the structure as the input random variables, rather than more "primitive" quantities like geometry or material variation. This modal information is much more comprehensive and easily measured than the "primitive" information. The probabilistic analysis is carried out using either response surface reliability methods or Monte Carlo simulation. In previous work, the feasibility of the PDS method applied to a simple seven degree-of-freedom spring-mass system was verified. In this paper, extensive issues involved with applying the method to a realistic three-substructure system are examined, and free and forced response analyses are performed. The results from using the method are promising, especially when the lack of alternatives for obtaining quantitative output for probabilistic structures is considered.
Experimental demonstration of graph-state quantum secret sharing.
Bell, B A; Markham, D; Herrera-Martí, D A; Marin, A; Wadsworth, W J; Rarity, J G; Tame, M S
2014-11-21
Quantum communication and computing offer many new opportunities for information processing in a connected world. Networks using quantum resources with tailor-made entanglement structures have been proposed for a variety of tasks, including distributing, sharing and processing information. Recently, a class of states known as graph states has emerged, providing versatile quantum resources for such networking tasks. Here we report an experimental demonstration of graph state-based quantum secret sharing--an important primitive for a quantum network with applications ranging from secure money transfer to multiparty quantum computation. We use an all-optical setup, encoding quantum information into photons representing a five-qubit graph state. We find that one can reliably encode, distribute and share quantum information amongst four parties, with various access structures based on the complex connectivity of the graph. Our results show that graph states are a promising approach for realising sophisticated multi-layered communication protocols in quantum networks.
Transit Reliability Information Program (TRIP) : Final Technical Report
DOT National Transportation Integrated Search
1984-05-01
The Transit Reliability Information Program (TRIP) is a government-initiated program to assist the transit industry in satisfying its need for rail transit car subsystem reliability information. TRIP provided this assistance through the operation of ...
Transit Reliability Information Program (TRIP) Phase I Report
DOT National Transportation Integrated Search
1981-06-01
The Transit Reliability Information Program (TRIP) is a government initiated program to assist the transit industry in satisfying its need for transit reliability information. TRIP provides this assistance through the operation of a national reliabil...
Wagner, Flávia; Martel, Michelle M; Cogo-Moreira, Hugo; Maia, Carlos Renato Moreira; Pan, Pedro Mario; Rohde, Luis Augusto; Salum, Giovanni Abrahão
2016-01-01
The best structural model for attention-deficit/hyperactivity disorder (ADHD) symptoms remains a matter of debate. The objective of this study is to test the fit and factor reliability of competing models of the dimensional structure of ADHD symptoms in a sample of randomly selected and high-risk children and pre-adolescents from Brazil. Our sample comprised 2512 children aged 6-12 years from 57 schools in Brazil. The ADHD symptoms were assessed using parent report on the development and well-being assessment (DAWBA). Fit indexes from confirmatory factor analysis were used to test unidimensional, correlated, and bifactor models of ADHD, the latter including "g" ADHD and "s" symptom domain factors. Reliability of all models was measured with omega coefficients. A bifactor model with one general factor and three specific factors (inattention, hyperactivity, impulsivity) exhibited the best fit to the data, according to fit indices, as well as the most consistent factor loadings. However, based on omega reliability statistics, the specific inattention, hyperactivity, and impulsivity dimensions provided very little reliable information after accounting for the reliable general ADHD factor. Our study presents some psychometric evidence that ADHD specific ("s") factors might be unreliable after taking common ("g" factor) variance into account. These results are in accordance with the lack of longitudinal stability among subtypes, the absence of dimension-specific molecular genetic findings and non-specific effects of treatment strategies. Therefore, researchers and clinicians might most effectively rely on the "g" ADHD to characterize ADHD dimensional phenotype, based on currently available symptom items.
NASA Astrophysics Data System (ADS)
Gontrani, Lorenzo; Caminiti, Ruggero; Salma, Umme; Campetella, Marco
2017-09-01
We present here a structural and vibrational analysis of melted methylammonium nitrate, the simplest compound of the family of alkylammonium nitrates. The static and dynamical features calculated were endorsed by comparing the experimental X-ray data with the theoretical ones. A reliable description cannot be obtained with classical molecular dynamics owing to polarization effects. Contrariwise, the structure factor and the vibrational frequencies obtained from ab initio molecular dynamics trajectories are in very good agreement with the experiment. A careful analysis has provided additional information on the complex hydrogen bonding network that exists in this liquid.
System reliability approaches for advanced propulsion system structures
NASA Technical Reports Server (NTRS)
Cruse, T. A.; Mahadevan, S.
1991-01-01
This paper identifies significant issues that pertain to the estimation and use of system reliability in the design of advanced propulsion system structures. Linkages between the reliabilities of individual components and their effect on system design issues such as performance, cost, availability, and certification are examined. The need for system reliability computation to address the continuum nature of propulsion system structures and synergistic progressive damage modes has been highlighted. Available system reliability models are observed to apply only to discrete systems. Therefore a sequential structural reanalysis procedure is formulated to rigorously compute the conditional dependencies between various failure modes. The method is developed in a manner that supports both top-down and bottom-up analyses in system reliability.
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
Alba-Ruiz, Ruben; Bermúdez-Tamayo, Clara; Pernett, Jaime Jiménez; Garcia-Gutierrez, Jose Francisco; Cózar-Olmo, José Manuel; Valero-Aguilera, Beatriz
2013-12-01
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. 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. 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. 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.
Questioning reliability assessments of health information on social media.
Dalmer, Nicole K
2017-01-01
This narrative review examines assessments of the reliability of online health information retrieved through social media to ascertain whether health information accessed or disseminated through social media should be evaluated differently than other online health information. Several medical, library and information science, and interdisciplinary databases were searched using terms relating to social media, reliability, and health information. While social media's increasing role in health information consumption is recognized, studies are dominated by investigations of traditional (i.e., non-social media) sites. To more richly assess constructions of reliability when using social media for health information, future research must focus on health consumers' unique contexts, virtual relationships, and degrees of trust within their social networks.
Recent advances in computational structural reliability analysis methods
NASA Astrophysics Data System (ADS)
Thacker, Ben H.; Wu, Y.-T.; Millwater, Harry R.; Torng, Tony Y.; Riha, David S.
1993-10-01
The goal of structural reliability analysis is to determine the probability that the structure will adequately perform its intended function when operating under the given environmental conditions. Thus, the notion of reliability admits the possibility of failure. Given the fact that many different modes of failure are usually possible, achievement of this goal is a formidable task, especially for large, complex structural systems. The traditional (deterministic) design methodology attempts to assure reliability by the application of safety factors and conservative assumptions. However, the safety factor approach lacks a quantitative basis in that the level of reliability is never known and usually results in overly conservative designs because of compounding conservatisms. Furthermore, problem parameters that control the reliability are not identified, nor their importance evaluated. A summary of recent advances in computational structural reliability assessment is presented. A significant level of activity in the research and development community was seen recently, much of which was directed towards the prediction of failure probabilities for single mode failures. The focus is to present some early results and demonstrations of advanced reliability methods applied to structural system problems. This includes structures that can fail as a result of multiple component failures (e.g., a redundant truss), or structural components that may fail due to multiple interacting failure modes (e.g., excessive deflection, resonate vibration, or creep rupture). From these results, some observations and recommendations are made with regard to future research needs.
Recent advances in computational structural reliability analysis methods
NASA Technical Reports Server (NTRS)
Thacker, Ben H.; Wu, Y.-T.; Millwater, Harry R.; Torng, Tony Y.; Riha, David S.
1993-01-01
The goal of structural reliability analysis is to determine the probability that the structure will adequately perform its intended function when operating under the given environmental conditions. Thus, the notion of reliability admits the possibility of failure. Given the fact that many different modes of failure are usually possible, achievement of this goal is a formidable task, especially for large, complex structural systems. The traditional (deterministic) design methodology attempts to assure reliability by the application of safety factors and conservative assumptions. However, the safety factor approach lacks a quantitative basis in that the level of reliability is never known and usually results in overly conservative designs because of compounding conservatisms. Furthermore, problem parameters that control the reliability are not identified, nor their importance evaluated. A summary of recent advances in computational structural reliability assessment is presented. A significant level of activity in the research and development community was seen recently, much of which was directed towards the prediction of failure probabilities for single mode failures. The focus is to present some early results and demonstrations of advanced reliability methods applied to structural system problems. This includes structures that can fail as a result of multiple component failures (e.g., a redundant truss), or structural components that may fail due to multiple interacting failure modes (e.g., excessive deflection, resonate vibration, or creep rupture). From these results, some observations and recommendations are made with regard to future research needs.
Chan, Kin Sun
2018-01-01
Objectives This study aimed to evaluate the internal consistency, reliability, convergent validity, known-group comparisons, and structural validity of the Chinese version of Fear of Intimacy with Helping Professionals (C–FIS–HP) scale in Macau. Methods A cross-sectional design was used on a sample of 593 older people in 6 health centers. We used Chinese version of Exercise of Self-Care Agency Scale (C-ESCAS) and Morisky 4-item medication adherence scale to evaluate self-care actions and medication adherence. The internal consistency and reliability of C–FIS–HP were analyzed using the Spearman-Brown split-half reliability, Cronbach’s alpha, and test–retest reliability. Convergent validity was tested the construct of C–FIS–HP and self-care actions. Known-group comparisons differentiated predefined groups in an expected direction. Two separated samples were used to test the structural validity. An exploratory factor analysis (EFA) tested the factor structure of C–FISHP using the principal axis factoring. A confirmatory factor analysis (CFA) was further conducted to confirm the factor structure constructed in the prior EFA. Results The C–FIS–HP had a Spearman-Brown split-half coefficient, Cronbach’s alpha, and intraclass correlation coefficient of 0.96, 0.93, and 0.96, respectively. Convergent validity was satisfactory with significantly correlations between the C-FIS-HP and C-ESCAS. C–FIS–HP to differentiate the differences between high-, moderate-, and low- medication adherence groups. EFA demonstrated a two-factor structure among 297 older people. A first-order CFA was performed to confirm the construct dimensionality of C–FIS–HP with satisfactory fit indices (NFI = 0.92; IFI = 0.95; TLI = 0.94; CFI = 0.95 and RMSEA = 0.07) among 296 older people. Conclusions C–FIS–HP is a reliable and valid test for assessing helping relationships in older Chinese people. Health professionals can use C–FIS–HP as a clinical tool to assess the comfort level of patients in a helping relationship, and use this information to develop culturally sensitive therapeutic interventions and treatment plans. Further studies need to be conducted concerning the different psychometric properties, as well as the application of C–FIS–HP in various regions. PMID:29795563
Mrożek-Budzyn, Dorota; Kiełtyka, Agnieszka; Mróz, Elżbieta
Campaigns against vaccinations in Poland have been increasingly more frequently observed in recent years, that was the reason of bigger number of parents refusing a consent for their children immunization. The aim of study was to determine the sources of information which significantly influence mothers’ opinions about vaccinations. A survey was conducted among 154 randomly selected mothers hospitalized after childbearing in two hospitals in Krakow and Myslenice at the end of 2014 and in 2015. The research tool was the author’s structured questionnaire interview. The majority of mothers regarded vaccinations as an efficient method of children protection against infectious diseases. Nevertheless, a few percent of women admitted that it is not efficient method or had no opinion about it. The mothers’ confidence was higher for vaccines known for many years compared to new formulations – 23.7% did not trust them and 22.4% had no statement on it. The most of respondents claimed that the safety of polyvalent vaccines is lower than single formulas, and were convinced that children receive too many vaccines. About 54.6% of mothers had no opinion and 13.6% admitted that children with chronic diseases should not be vaccinated. Depending on the question content from 3.2% to 54.6% respondents had no opinion about included vaccination issues. The pediatricians and family doctors were the main and the most reliable source of information about vaccinations. The reliability of doctors was assessed higher by citizens of big city compared to women living in rural area (statistically significant). Above 50% of mothers used mass media as a source of information about vaccination but less than 8% regarded them as reliable. Despite the wide access to different source of information, the newborns’ mothers too often had the knowledge and opinions about vaccination inconsistent with data derived from medical facts. Furthermore, significant group of mothers had no opinions about important issues with respect to vaccinations. At the beginning of infants life when parents decide of their child immunization, the reliable knowledge about that issue should be delivered by GPs because the other sources of information are assessed as much less reliable.
Sun, Ning; Li, Qiu-Jie; Lv, Dong-Mei; Lu, Gui-Zhi; Lin, Ping; An, Xue-Mei
2014-10-01
The present study was conducted to evaluate the psychometric properties of a newly adapted Chinese version of an instrument designed to measure structural empowerment among staff nurses. Structural empowerment has been shown to be important to nurses in Western cultures, but its importance in China is unknown. A convenience sample of 650 staff nurses was selected from six hospitals in Harbin, China. After linguistic adaptation using the forward-backward translation method, the 19-item Conditions of Work Effectiveness Questionnaire-II (CWEQ-II-CV) was answered by participants. Content validity, Cronbach's alpha, item-to-total correlation and exploratory factor analysis were used to assess the reliability and validity of the translated instrument. In the factor analysis, a six-factor solution was found to be reasonable with the sub-dimensions of structural empowerment that included support (three items), resources (three items), information (three items), opportunity (three items), formal power (three items) and informal power (four items). Cronbach's alpha coefficient for the total instrument was 0.92 and ranged from 0.68 to 0.86 in the six subscales. The item-to-total correlation coefficients ranged from 0.48 to 0.80. The findings also gave support for content validity. Evidence was found to support the reliability and validity of the CWEQ-II-CV scale that measures the quality of the work environment for nurses from a structural empowerment perspective. The translated version of CWEQ-II-CV can provide an effective evaluation tool for structural empowerment in the Chinese nursing workplace. © 2013 John Wiley & Sons Ltd.
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…
Reliable fusion of control and sensing in intelligent machines. Thesis
NASA Technical Reports Server (NTRS)
Mcinroy, John E.
1991-01-01
Although robotics research has produced a wealth of sophisticated control and sensing algorithms, very little research has been aimed at reliably combining these control and sensing strategies so that a specific task can be executed. To improve the reliability of robotic systems, analytic techniques are developed for calculating the probability that a particular combination of control and sensing algorithms will satisfy the required specifications. The probability can then be used to assess the reliability of the design. An entropy formulation is first used to quickly eliminate designs not capable of meeting the specifications. Next, a framework for analyzing reliability based on the first order second moment methods of structural engineering is proposed. To ensure performance over an interval of time, lower bounds on the reliability of meeting a set of quadratic specifications with a Gaussian discrete time invariant control system are derived. A case study analyzing visual positioning in robotic system is considered. The reliability of meeting timing and positioning specifications in the presence of camera pixel truncation, forward and inverse kinematic errors, and Gaussian joint measurement noise is determined. This information is used to select a visual sensing strategy, a kinematic algorithm, and a discrete compensator capable of accomplishing the desired task. Simulation results using PUMA 560 kinematic and dynamic characteristics are presented.
Blouin, Danielle; Day, Andrew G.; Pavlov, Andrey
2011-01-01
Background Although never directly compared, structured interviews are reported as being more reliable than unstructured interviews. This study compared the reliability of both types of interview when applied to a common pool of applicants for positions in an emergency medicine residency program. Methods In 2008, one structured interview was added to the two unstructured interviews traditionally used in our resident selection process. A formal job analysis using the critical incident technique guided the development of the structured interview tool. This tool consisted of 7 scenarios assessing 4 of the domains deemed essential for success as a resident in this program. The traditional interview tool assessed 5 general criteria. In addition to these criteria, the unstructured panel members were asked to rate each candidate on the same 4 essential domains rated by the structured panel members. All 3 panels interviewed all candidates. Main outcomes were the overall, interitem, and interrater reliabilities, the correlations between interview panels, and the dimensionality of each interview tool. Results Thirty candidates were interviewed. The overall reliability reached 0.43 for the structured interview, and 0.81 and 0.71 for the unstructured interviews. Analyses of the variance components showed a high interrater, low interitem reliability for the structured interview, and a high interrater, high interitem reliability for the unstructured interviews. The summary measures from the 2 unstructured interviews were significantly correlated, but neither was correlated with the structured interview. Only the structured interview was multidimensional. Conclusions A structured interview did not yield a higher overall reliability than both unstructured interviews. The lower reliability is explained by a lower interitem reliability, which in turn is due to the multidimensionality of the interview tool. Both unstructured panels consistently rated a single dimension, even when prompted to assess the 4 specific domains established as essential to succeed in this residency program. PMID:23205201
Blouin, Danielle; Day, Andrew G; Pavlov, Andrey
2011-12-01
Although never directly compared, structured interviews are reported as being more reliable than unstructured interviews. This study compared the reliability of both types of interview when applied to a common pool of applicants for positions in an emergency medicine residency program. In 2008, one structured interview was added to the two unstructured interviews traditionally used in our resident selection process. A formal job analysis using the critical incident technique guided the development of the structured interview tool. This tool consisted of 7 scenarios assessing 4 of the domains deemed essential for success as a resident in this program. The traditional interview tool assessed 5 general criteria. In addition to these criteria, the unstructured panel members were asked to rate each candidate on the same 4 essential domains rated by the structured panel members. All 3 panels interviewed all candidates. Main outcomes were the overall, interitem, and interrater reliabilities, the correlations between interview panels, and the dimensionality of each interview tool. Thirty candidates were interviewed. The overall reliability reached 0.43 for the structured interview, and 0.81 and 0.71 for the unstructured interviews. Analyses of the variance components showed a high interrater, low interitem reliability for the structured interview, and a high interrater, high interitem reliability for the unstructured interviews. The summary measures from the 2 unstructured interviews were significantly correlated, but neither was correlated with the structured interview. Only the structured interview was multidimensional. A structured interview did not yield a higher overall reliability than both unstructured interviews. The lower reliability is explained by a lower interitem reliability, which in turn is due to the multidimensionality of the interview tool. Both unstructured panels consistently rated a single dimension, even when prompted to assess the 4 specific domains established as essential to succeed in this residency program.
Research on Self-Reconfigurable Modular Robot System
NASA Astrophysics Data System (ADS)
Kamimura, Akiya; Murata, Satoshi; Yoshida, Eiichi; Kurokawa, Haruhisa; Tomita, Kohji; Kokaji, Shigeru
Growing complexity of artificial systems arises reliability and flexibility issues of large system design. Robots are not exception of this, and many attempts have been made to realize reliable and flexible robot systems. Distributed modular composition of robot is one of the most effective approaches to attain such abilities and has a potential to adapt to its surroundings by changing its configuration autonomously according to information of surroundings. In this paper, we propose a novel three-dimensional self-reconfigurable robotic module. Each module has a very simple structure that consists of two semi-cylindrical parts connected by a link. The modular system is capable of not only building static structure but also generating dynamic robotic motion. We present details of the mechanical/electrical design of the developed module and its control system architecture. Experiments using ten modules with centralized control demonstrate robotic configuration change, crawling locomotion and three types of quadruped locomotion.
CASTp 3.0: computed atlas of surface topography of proteins.
Tian, Wei; Chen, Chang; Lei, Xue; Zhao, Jieling; Liang, Jie
2018-06-01
Geometric and topological properties of protein structures, including surface pockets, interior cavities and cross channels, are of fundamental importance for proteins to carry out their functions. Computed Atlas of Surface Topography of proteins (CASTp) is a web server that provides online services for locating, delineating and measuring these geometric and topological properties of protein structures. It has been widely used since its inception in 2003. In this article, we present the latest version of the web server, CASTp 3.0. CASTp 3.0 continues to provide reliable and comprehensive identifications and quantifications of protein topography. In addition, it now provides: (i) imprints of the negative volumes of pockets, cavities and channels, (ii) topographic features of biological assemblies in the Protein Data Bank, (iii) improved visualization of protein structures and pockets, and (iv) more intuitive structural and annotated information, including information of secondary structure, functional sites, variant sites and other annotations of protein residues. The CASTp 3.0 web server is freely accessible at http://sts.bioe.uic.edu/castp/.
Assessment of and standardization for quantitative nondestructive test
NASA Technical Reports Server (NTRS)
Neuschaefer, R. W.; Beal, J. B.
1972-01-01
Present capabilities and limitations of nondestructive testing (NDT) as applied to aerospace structures during design, development, production, and operational phases are assessed. It will help determine what useful structural quantitative and qualitative data may be provided from raw materials to vehicle refurbishment. This assessment considers metal alloys systems and bonded composites presently applied in active NASA programs or strong contenders for future use. Quantitative and qualitative data has been summarized from recent literature, and in-house information, and presented along with a description of those structures or standards where the information was obtained. Examples, in tabular form, of NDT technique capabilities and limitations have been provided. NDT techniques discussed and assessed were radiography, ultrasonics, penetrants, thermal, acoustic, and electromagnetic. Quantitative data is sparse; therefore, obtaining statistically reliable flaw detection data must be strongly emphasized. The new requirements for reusable space vehicles have resulted in highly efficient design concepts operating in severe environments. This increases the need for quantitative NDT evaluation of selected structural components, the end item structure, and during refurbishment operations.
Structures and Materials Experimental Facilities and Capabilities Catalog
NASA Technical Reports Server (NTRS)
Horta, Lucas G. (Compiler); Kurtz-Husch, Jeanette D. (Compiler)
2000-01-01
The NASA Center of Excellent for Structures and Materials at Langley Research Center is responsible for conducting research and developing useable technology in the areas of advanced materials and processing technologies, durability, damage tolerance, structural concepts, advanced sensors, intelligent systems, aircraft ground operations, reliability, prediction tools, performance validation, aeroelastic response, and structural dynamics behavior for aerospace vehicles. Supporting the research activities is a complementary set of facilities and capabilities documented in this report. Because of the volume of information, the information collected was restricted in most cases to one page. Specific questions from potential customers or partners should be directed to the points of contacts provided with the various capabilities. Grouping of the equipment is by location as opposed to function. Geographical information of the various buildings housing the equipment is also provided. Since this is the first time that such an inventory is ever collected at Langley it is by no means complete. It is estimated that over 90 percent of the equipment capabilities at hand are included but equipment is continuously being updated and will be reported in the future.
Radiologic imaging of the renal parenchyma structure and function.
Grenier, Nicolas; Merville, Pierre; Combe, Christian
2016-06-01
Radiologic imaging has the potential to identify several functional and/or structural biomarkers of acute and chronic kidney diseases that are useful diagnostics to guide patient management. A renal ultrasound examination can provide information regarding the gross anatomy and macrostructure of the renal parenchyma, and ultrasound imaging modalities based on Doppler or elastography techniques can provide haemodynamic and structural information, respectively. CT is also able to combine morphological and functional information, but the use of CT is limited due to the required exposure to X-ray irradiation and a risk of contrast-induced nephropathy following intravenous injection of a radio-contrast agent. MRI can be used to identify a wide range of anatomical and physiological parameters at the tissue and even cellular level, such as tissue perfusion, oxygenation, water diffusion, cellular phagocytic activity, tissue stiffness, and level of renal filtration. The ability of MRI to provide valuable information for most of these parameters within a renal context is still in development and requires more clinical experience, harmonization of technical procedures, and an evaluation of reliability and validity on a large scale.
Sexual Harassment Retaliation Climate DEOCS 4.1 Construct Validity Summary
2017-08-01
exploratory factor analysis, and bivariate correlations (sample 1) 2) To determine the factor structure of the remaining (final) questions via...statistics, reliability analysis, exploratory factor analysis, and bivariate correlations of the prospective Sexual Harassment Retaliation Climate...reported by the survey requester). For information regarding the composition of sample, refer to Table 1. Table 1. Sample 1 Demographics n
ERIC Educational Resources Information Center
Rogers, Maria; Markel, Clarisa; Midgett, Jonathan D.; Ryan, Bruce A.; Tannock, Rosemary
2014-01-01
Practitioners of Conjoint Behavioral Consultation rely on several sources of information to assist in planning and evaluation of consultation efforts. Parental involvement in the home is an important aspect in Conjoint Behavioral Consultation, yet there are few questionnaires available to practitioners to assess this important construct,…
Yang, Huan; Meijer, Hil G E; Buitenweg, Jan R; van Gils, Stephan A
2016-01-01
Healthy or pathological states of nociceptive subsystems determine different stimulus-response relations measured from quantitative sensory testing. In turn, stimulus-response measurements may be used to assess these states. In a recently developed computational model, six model parameters characterize activation of nerve endings and spinal neurons. However, both model nonlinearity and limited information in yes-no detection responses to electrocutaneous stimuli challenge to estimate model parameters. Here, we address the question whether and how one can overcome these difficulties for reliable parameter estimation. First, we fit the computational model to experimental stimulus-response pairs by maximizing the likelihood. To evaluate the balance between model fit and complexity, i.e., the number of model parameters, we evaluate the Bayesian Information Criterion. We find that the computational model is better than a conventional logistic model regarding the balance. Second, our theoretical analysis suggests to vary the pulse width among applied stimuli as a necessary condition to prevent structural non-identifiability. In addition, the numerically implemented profile likelihood approach reveals structural and practical non-identifiability. Our model-based approach with integration of psychophysical measurements can be useful for a reliable assessment of states of the nociceptive system.
NASA Astrophysics Data System (ADS)
Strotov, Valery V.; Taganov, Alexander I.; Konkin, Yuriy V.; Kolesenkov, Aleksandr N.
2017-10-01
Task of processing and analysis of obtained Earth remote sensing data on ultra-small spacecraft board is actual taking into consideration significant expenditures of energy for data transfer and low productivity of computers. Thereby, there is an issue of effective and reliable storage of the general information flow obtained from onboard systems of information collection, including Earth remote sensing data, into a specialized data base. The paper has considered peculiarities of database management system operation with the multilevel memory structure. For storage of data in data base the format has been developed that describes a data base physical structure which contains required parameters for information loading. Such structure allows reducing a memory size occupied by data base because it is not necessary to store values of keys separately. The paper has shown architecture of the relational database management system oriented into embedment into the onboard ultra-small spacecraft software. Data base for storage of different information, including Earth remote sensing data, can be developed by means of such database management system for its following processing. Suggested database management system architecture has low requirements to power of the computer systems and memory resources on the ultra-small spacecraft board. Data integrity is ensured under input and change of the structured information.
Structuring Legacy Pathology Reports by openEHR Archetypes to Enable Semantic Querying.
Kropf, Stefan; Krücken, Peter; Mueller, Wolf; Denecke, Kerstin
2017-05-18
Clinical information is often stored as free text, e.g. in discharge summaries or pathology reports. These documents are semi-structured using section headers, numbered lists, items and classification strings. However, it is still challenging to retrieve relevant documents since keyword searches applied on complete unstructured documents result in many false positive retrieval results. We are concentrating on the processing of pathology reports as an example for unstructured clinical documents. The objective is to transform reports semi-automatically into an information structure that enables an improved access and retrieval of relevant data. The data is expected to be stored in a standardized, structured way to make it accessible for queries that are applied to specific sections of a document (section-sensitive queries) and for information reuse. Our processing pipeline comprises information modelling, section boundary detection and section-sensitive queries. For enabling a focused search in unstructured data, documents are automatically structured and transformed into a patient information model specified through openEHR archetypes. The resulting XML-based pathology electronic health records (PEHRs) are queried by XQuery and visualized by XSLT in HTML. Pathology reports (PRs) can be reliably structured into sections by a keyword-based approach. The information modelling using openEHR allows saving time in the modelling process since many archetypes can be reused. The resulting standardized, structured PEHRs allow accessing relevant data by retrieving data matching user queries. Mapping unstructured reports into a standardized information model is a practical solution for a better access to data. Archetype-based XML enables section-sensitive retrieval and visualisation by well-established XML techniques. Focussing the retrieval to particular sections has the potential of saving retrieval time and improving the accuracy of the retrieval.
Reliability Analysis of Sealing Structure of Electromechanical System Based on Kriging Model
NASA Astrophysics Data System (ADS)
Zhang, F.; Wang, Y. M.; Chen, R. W.; Deng, W. W.; Gao, Y.
2018-05-01
The sealing performance of aircraft electromechanical system has a great influence on flight safety, and the reliability of its typical seal structure is analyzed by researcher. In this paper, we regard reciprocating seal structure as a research object to study structural reliability. Having been based on the finite element numerical simulation method, the contact stress between the rubber sealing ring and the cylinder wall is calculated, and the relationship between the contact stress and the pressure of the hydraulic medium is built, and the friction force on different working conditions are compared. Through the co-simulation, the adaptive Kriging model obtained by EFF learning mechanism is used to describe the failure probability of the seal ring, so as to evaluate the reliability of the sealing structure. This article proposes a new idea of numerical evaluation for the reliability analysis of sealing structure, and also provides a theoretical basis for the optimal design of sealing structure.
Boileau, C; Martel-Pelletier, J; Abram, F; Raynauld, J-P; Troncy, E; D'Anjou, M-A; Moreau, M; Pelletier, J-P
2008-07-01
Osteoarthritis (OA) structural changes take place over decades in humans. MRI can provide precise and reliable information on the joint structure and changes over time. In this study, we investigated the reliability of quantitative MRI in assessing knee OA structural changes in the experimental anterior cruciate ligament (ACL) dog model of OA. OA was surgically induced by transection of the ACL of the right knee in five dogs. High resolution three dimensional MRI using a 1.5 T magnet was performed at baseline, 4, 8 and 26 weeks post surgery. Cartilage volume/thickness, cartilage defects, trochlear osteophyte formation and subchondral bone lesion (hypersignal) were assessed on MRI images. Animals were killed 26 weeks post surgery and macroscopic evaluation was performed. There was a progressive and significant increase over time in the loss of knee cartilage volume, the cartilage defect and subchondral bone hypersignal. The trochlear osteophyte size also progressed over time. The greatest cartilage loss at 26 weeks was found on the tibial plateaus and in the medial compartment. There was a highly significant correlation between total knee cartilage volume loss or defect and subchondral bone hypersignal, and also a good correlation between the macroscopic and the MRI findings. This study demonstrated that MRI is a useful technology to provide a non-invasive and reliable assessment of the joint structural changes during the development of OA in the ACL dog model. The combination of this OA model with MRI evaluation provides a promising tool for the evaluation of new disease-modifying osteoarthritis drugs (DMOADs).
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
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.
How Reliable Are Informal Reading Inventories?
ERIC Educational Resources Information Center
Spector, Janet E.
2005-01-01
Informal Reading Inventories (IRI) are often recommended as instructionally relevant measures of reading. However, they have also been criticized for inattention to technical quality. Examination of reliability evidence in nine recently revised IRIs revealed that fewer than half report reliability. Several appear to have sufficient reliability for…
The EORTC information questionnaire, EORTC QLQ-INFO25. Validation study for Spanish patients.
Arraras, Juan Ignacio; Manterola, Ana; Hernández, Berta; Arias de la Vega, Fernando; Martínez, Maite; Vila, Meritxell; Eito, Clara; Vera, Ruth; Domínguez, Miguel Ángel
2011-06-01
The EORTC QLQ-INFO25 evaluates the information received by cancer patients. This study assesses the psychometric properties of the QLQ-INFO25 when applied to a sample of Spanish patients. A total of 169 patients with different cancers and stages of disease completed the EORTC QLQINFO25, the EORTC QLQ-C30 and the information scales of the inpatient satisfaction module EORTC IN-PATSAT32 on two occasions during the patients' treatment and follow- up period. Psychometric evaluation of the structure, reliability, validity and responsiveness to changes was conducted. Patient acceptability was assessed with a debriefing questionnaire. Multi-trait scaling confirmed the 4 multi-item scales (information about disease, medical tests, treatment and other services) and eight single items. All items met the standards for convergent validity and all except one met the standards of item discriminant validity. Internal consistency for all scales (α>0.70) and the whole questionnaire (α>0.90) was adequate in the three measurements, except information about the disease (0.67) and other services (0.68) in the first measurement, as was test-retest reliability (intraclass correlations >0.70). Correlations with related areas of IN-PATSAT32 (r>0.40) supported convergent validity. Divergent validity was confirmed through low correlations with EORTC QLQ-C30 scales (r<0.30). The EORTC QLQ-INFO-25 discriminated among groups based on gender, age, education, levels of anxiety and depression, treatment line, wish for information and satisfaction. One scale and an item showed changes over time. The EORTC QLQ-INFO 25 is a reliable and valid instrument when applied to a sample of Spanish cancer patients. These results are in line with those of the EORTC validation study.
NASA Astrophysics Data System (ADS)
Serva, A.; Migliorati, V.; Lapi, A.; D'Angelo, P.
2016-05-01
The structural properties of geminal dicationic ionic liquids ([Cn (mim)2]Br2)/water mixtures have been investigated by means of extended X-ray absorption fine structure (EXAFS) spectroscopy and Molecular Dynamics (MD) simulations. This synergic approach allowed us to assess the reliability of the MD results and to provide accurate structural information about the first coordination shell of the Br- ion. We found that the local environment around the anion changes as a function of the water concentration, while it is the same independently from the length of the bridge-alkyl chain. Moreover, as regards the long-range structural organization, no tail-tail aggregation occurs with increasing alkyl chain length.
Foraging Bumble Bees Weigh the Reliability of Personal and Social Information.
Dunlap, Aimee S; Nielsen, Matthew E; Dornhaus, Anna; Papaj, Daniel R
2016-05-09
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. Copyright © 2016 Elsevier Ltd. All rights reserved.
How to integrate quantitative information into imaging reports for oncologic patients.
Martí-Bonmatí, L; Ruiz-Martínez, E; Ten, A; Alberich-Bayarri, A
2018-05-01
Nowadays, the images and information generated in imaging tests, as well as the reports that are issued, are digital and represent a reliable source of data. Reports can be classified according to their content and to the type of information they include into three main types: organized (free text in natural language), predefined (with templates and guidelines elaborated with previously determined natural language like that used in BI-RADS and PI-RADS), or structured (with drop-down menus displaying questions with various possible answers that have been agreed on with the rest of the multidisciplinary team, which use standardized lexicons and are structured in the form of a database with data that can be traced and exploited with statistical tools and data mining). The structured report, compatible with Management of Radiology Report Templates (MRRT), makes it possible to incorporate quantitative information related with the digital analysis of the data from the acquired images to accurately and precisely describe the properties and behavior of tissues by means of radiomics (characteristics and parameters). In conclusion, structured digital information (images, text, measurements, radiomic features, and imaging biomarkers) should be integrated into computerized reports so that they can be indexed in large repositories. Radiologic databanks are fundamental for exploiting health information, phenotyping lesions and diseases, and extracting conclusions in personalized medicine. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.
Jacques, David A; Guss, Jules Mitchell; Trewhella, Jill
2012-05-17
Small-angle scattering is becoming an increasingly popular tool for the study of bio-molecular structures in solution. The large number of publications with 3D-structural models generated from small-angle solution scattering data has led to a growing consensus for the need to establish a standard reporting framework for their publication. The International Union of Crystallography recently established a set of guidelines for the necessary information required for the publication of such structural models. Here we describe the rationale for these guidelines and the importance of standardising the way in which small-angle scattering data from bio-molecules and associated structural interpretations are reported.
Ardalan, Ali; Sohrabizadeh, Sanaz
2016-02-25
Iran is placed among countries suffering from the highest number of earthquake casualties. Household preparedness, as one component of risk reduction efforts, is often supported in quake-prone areas. In Iran, lack of a valid and reliable household preparedness tool was reported by previous disaster studies. This study is aimed to fill this gap by developing a valid and reliable tool for assessing household preparedness in the event of an earthquake. This survey was conducted through three phases including literature review and focus group discussions with the participation of eight key informants, validity measurements and reliability measurements. Field investigation was completed with the participation of 450 households within three provinces of Iran. Content validity, construct validity, the use of factor analysis; internal consistency using Cronbach's alpha coefficient, and test-retest reliability were carried out to develop the tool. Based on the CVIs, ranging from 0.80 to 0.100, and exploratory factor analysis with factor loading of more than 0.5, all items were valid. The amount of Cronbach's alpha (0.7) and test-retest examination by Spearman correlations indicated that the scale was also reliable. The final instrument consisted of six categories and 18 questions including actions at the time of earthquakes, nonstructural safety, structural safety, hazard map, communications, drill, and safety skills. Using a Persian-version tool that is adjusted to the socio-cultural determinants and native language may result in more trustful information on earthquake preparedness. It is suggested that disaster managers and researchers apply this tool in their future household preparedness projects. Further research is needed to make effective policies and plans for transforming preparedness knowledge into behavior.
Estimation of Reliability Coefficients Using the Test Information Function and Its Modifications.
ERIC Educational Resources Information Center
Samejima, Fumiko
1994-01-01
The reliability coefficient is predicted from the test information function (TIF) or two modified TIF formulas and a specific trait distribution. Examples illustrate the variability of the reliability coefficient across different trait distributions, and results are compared with empirical reliability coefficients. (SLD)
77 FR 6550 - Commission Information Collection Activities (FERC-725A); Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-08
... submitting the information collection FERC-725A, Mandatory Reliability Standards for the Bulk- Power System... Reliability Standard, in an order published in the Federal Register (76 FR 72197, 11/22/2011). FERC received...) 273-0873. SUPPLEMENTARY INFORMATION: Title: FERC-725A, Mandatory Reliability Standards for the Bulk...
NASA Astrophysics Data System (ADS)
Ighravwe, D. E.; Oke, S. A.; Adebiyi, K. A.
2018-03-01
This paper draws on the "human reliability" concept as a structure for gaining insight into the maintenance workforce assessment in a process industry. Human reliability hinges on developing the reliability of humans to a threshold that guides the maintenance workforce to execute accurate decisions within the limits of resources and time allocations. This concept offers a worthwhile point of deviation to encompass three elegant adjustments to literature model in terms of maintenance time, workforce performance and return-on-workforce investments. These fully explain the results of our influence. The presented structure breaks new grounds in maintenance workforce theory and practice from a number of perspectives. First, we have successfully implemented fuzzy goal programming (FGP) and differential evolution (DE) techniques for the solution of optimisation problem in maintenance of a process plant for the first time. The results obtained in this work showed better quality of solution from the DE algorithm compared with those of genetic algorithm and particle swarm optimisation algorithm, thus expressing superiority of the proposed procedure over them. Second, the analytical discourse, which was framed on stochastic theory, focusing on specific application to a process plant in Nigeria is a novelty. The work provides more insights into maintenance workforce planning during overhaul rework and overtime maintenance activities in manufacturing systems and demonstrated capacity in generating substantially helpful information for practice.
Piqueras, Jose A; Martín-Vivar, María; Sandin, Bonifacio; San Luis, Concepción; Pineda, David
2017-08-15
Anxiety and depression are among the most common mental disorders during childhood and adolescence. Among the instruments for the brief screening assessment of symptoms of anxiety and depression, the Revised Child Anxiety and Depression Scale (RCADS) is one of the more widely used. Previous studies have demonstrated the reliability of the RCADS for different assessment settings and different versions. The aims of this study were to examine the mean reliability of the RCADS and the influence of the moderators on the RCADS reliability. We searched in EBSCO, PsycINFO, Google Scholar, Web of Science, and NCBI databases and other articles manually from lists of references of extracted articles. A total of 146 studies were included in our meta-analysis. The RCADS showed robust internal consistency reliability in different assessment settings, countries, and languages. We only found that reliability of the RCADS was significantly moderated by the version of RCADS. However, these differences in reliability between different versions of the RCADS were slight and can be due to the number of items. We did not examine factor structure, factorial invariance across gender, age, or country, and test-retest reliability of the RCADS. The RCADS is a reliable instrument for cross-cultural use, with the advantage of providing more information with a low number of items in the assessment of both anxiety and depression symptoms in children and adolescents. Copyright © 2017. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Varlataya, S. K.; Evdokimov, V. E.; Urzov, A. Y.
2017-11-01
This article describes a process of calculating a certain complex information security system (CISS) reliability using the example of the technospheric security management model as well as ability to determine the frequency of its maintenance using the system reliability parameter which allows one to assess man-made risks and to forecast natural and man-made emergencies. The relevance of this article is explained by the fact the CISS reliability is closely related to information security (IS) risks. Since reliability (or resiliency) is a probabilistic characteristic of the system showing the possibility of its failure (and as a consequence - threats to the protected information assets emergence), it is seen as a component of the overall IS risk in the system. As it is known, there is a certain acceptable level of IS risk assigned by experts for a particular information system; in case of reliability being a risk-forming factor maintaining an acceptable risk level should be carried out by the routine analysis of the condition of CISS and its elements and their timely service. The article presents a reliability parameter calculation for the CISS with a mixed type of element connection, a formula of the dynamics of such system reliability is written. The chart of CISS reliability change is a S-shaped curve which can be divided into 3 periods: almost invariable high level of reliability, uniform reliability reduction, almost invariable low level of reliability. Setting the minimum acceptable level of reliability, the graph (or formula) can be used to determine the period of time during which the system would meet requirements. Ideally, this period should not be longer than the first period of the graph. Thus, the proposed method of calculating the CISS maintenance frequency helps to solve a voluminous and critical task of the information assets risk management.
Software reliability experiments data analysis and investigation
NASA Technical Reports Server (NTRS)
Walker, J. Leslie; Caglayan, Alper K.
1991-01-01
The objectives are to investigate the fundamental reasons which cause independently developed software programs to fail dependently, and to examine fault tolerant software structures which maximize reliability gain in the presence of such dependent failure behavior. The authors used 20 redundant programs from a software reliability experiment to analyze the software errors causing coincident failures, to compare the reliability of N-version and recovery block structures composed of these programs, and to examine the impact of diversity on software reliability using subpopulations of these programs. The results indicate that both conceptually related and unrelated errors can cause coincident failures and that recovery block structures offer more reliability gain than N-version structures if acceptance checks that fail independently from the software components are available. The authors present a theory of general program checkers that have potential application for acceptance tests.
Transit Reliability Information Program Participants Guidelines
DOT National Transportation Integrated Search
1981-03-01
The document provides guidelines for participation in the Transit Reliability Information Program (TRIP). TRIP is a government-initiated program designed to assist the transit industry in satisfying its need for transit equipment reliability data. TR...
The way to uncover community structure with core and diversity
NASA Astrophysics Data System (ADS)
Chang, Y. F.; Han, S. K.; Wang, X. D.
2018-07-01
Communities are ubiquitous in nature and society. Individuals that share common properties often self-organize to form communities. Avoiding the shortages of computation complexity, pre-given information and unstable results in different run, in this paper, we propose a simple and efficient method to deepen our understanding of the emergence and diversity of communities in complex systems. By introducing the rational random selection, our method reveals the hidden deterministic and normal diverse community states of community structure. To demonstrate this method, we test it with real-world systems. The results show that our method could not only detect community structure with high sensitivity and reliability, but also provide instructional information about the hidden deterministic community world and the real normal diverse community world by giving out the core-community, the real-community, the tide and the diversity. Thizs is of paramount importance in understanding, predicting, and controlling a variety of collective behaviors in complex systems.
Assessing Perceptions AbouT Hazardous Substances (PATHS): The PATHS questionnaire
Amlôt, Richard; Page, Lisa; Pearce, Julia; Wessely, Simon
2013-01-01
How people perceive the nature of a hazardous substance may determine how they respond when potentially exposed to it. We tested a new Perceptions AbouT Hazardous Substances (PATHS) questionnaire. In Study 1 (N = 21), we assessed the face validity of items concerning perceptions about eight properties of a hazardous substance. In Study 2 (N = 2030), we tested the factor structure, reliability and validity of the PATHS questionnaire across four qualitatively different substances. In Study 3 (N = 760), we tested the impact of information provision on Perceptions AbouT Hazardous Substances scores. Our results showed that our eight measures demonstrated good reliability and validity when used for non-contagious hazards. PMID:23104995
Chatterji, Madhabi
2002-01-01
This study examines validity of data generated by the School Readiness for Reforms: Leader Questionnaire (SRR-LQ) using an iterative procedure that combines classical and Rasch rating scale analysis. Following content-validation and pilot-testing, principal axis factor extraction and promax rotation of factors yielded a five factor structure consistent with the content-validated subscales of the original instrument. Factors were identified based on inspection of pattern and structure coefficients. The rotated factor pattern, inter-factor correlations, convergent validity coefficients, and Cronbach's alpha reliability estimates supported the hypothesized construct properties. To further examine unidimensionality and efficacy of the rating scale structures, item-level data from each factor-defined subscale were subjected to analysis with the Rasch rating scale model. Data-to-model fit statistics and separation reliability for items and persons met acceptable criteria. Rating scale results suggested consistency of expected and observed step difficulties in rating categories, and correspondence of step calibrations with increases in the underlying variables. The combined approach yielded more comprehensive diagnostic information on the quality of the five SRR-LQ subscales; further research is continuing.
Considering context: reliable entity networks through contextual relationship extraction
NASA Astrophysics Data System (ADS)
David, Peter; Hawes, Timothy; Hansen, Nichole; Nolan, James J.
2016-05-01
Existing information extraction techniques can only partially address the problem of exploiting unreadable-large amounts text. When discussion of events and relationships is limited to simple, past-tense, factual descriptions of events, current NLP-based systems can identify events and relationships and extract a limited amount of additional information. But the simple subset of available information that existing tools can extract from text is only useful to a small set of users and problems. Automated systems need to find and separate information based on what is threatened or planned to occur, has occurred in the past, or could potentially occur. We address the problem of advanced event and relationship extraction with our event and relationship attribute recognition system, which labels generic, planned, recurring, and potential events. The approach is based on a combination of new machine learning methods, novel linguistic features, and crowd-sourced labeling. The attribute labeler closes the gap between structured event and relationship models and the complicated and nuanced language that people use to describe them. Our operational-quality event and relationship attribute labeler enables Warfighters and analysts to more thoroughly exploit information in unstructured text. This is made possible through 1) More precise event and relationship interpretation, 2) More detailed information about extracted events and relationships, and 3) More reliable and informative entity networks that acknowledge the different attributes of entity-entity relationships.
Hallgren, Kevin A.; Greenfield, Brenna L.; Ladd, Benjamin O.
2016-01-01
Background Behavioral economic theories of drinking posit that the reinforcing value of engaging in activities with versus without alcohol influences drinking behavior. Measures of the reinforcement value of drugs and alcohol have been used in previous research, but little work has examined the psychometric properties of these measures. Objectives The present study aims to evaluate the factor structure, test-retest reliability, and concurrent validity of an alcohol-only version of the Adolescent Reinforcement Survey Schedule (ARSS-AUV). Methods A sample of 157 college student drinkers completed the ARSS-AUV at two time points 2–3 days apart. Test-retest reliability, hierarchical factor analysis, and correlations with other drinking measures were examined. Results Single, unidimensional general factors accounted for a majority of the variance in alcohol and alcohol-free reinforcement items. Residual factors emerged that typically represented alcohol or alcohol-free reinforcement while doing activities with friends, romantic or sexual partners, and family members. Individual ARSS-AUV items had fair-to-good test-retest reliability, while general and residual factors had excellent test-retest reliability. General alcohol reinforcement and alcohol reinforcement from friends and romantic partners were positively correlated with past-year alcohol consumption, heaviest drinking episode, and alcohol-related negative consequences. Alcohol-free reinforcement indices were unrelated to alcohol use or consequences. Conclusions/Importance The ARSS-AUV appears to demonstrate good reliability and mixed concurrent validity among college student drinkers. The instrument may provide useful information about alcohol reinforcement from various activities and people and could provide clinically-relevant information for prevention and treatment programs. PMID:27096713
Hallgren, Kevin A; Greenfield, Brenna L; Ladd, Benjamin O
2016-06-06
Behavioral economic theories of drinking posit that the reinforcing value of engaging in activities with versus without alcohol influences drinking behavior. Measures of the reinforcement value of drugs and alcohol have been used in previous research, but little work has examined the psychometric properties of these measures. The present study aims to evaluate the factor structure, test-retest reliability, and concurrent validity of an alcohol-only version of the Adolescent Reinforcement Survey Schedule (ARSS-AUV). A sample of 157 college student drinkers completed the ARSS-AUV at two time points 2-3 days apart. Test-retest reliability, hierarchical factor analysis, and correlations with other drinking measures were examined. Single, unidimensional general factors accounted for a majority of the variance in alcohol and alcohol-free reinforcement items. Residual factors emerged that typically represented alcohol or alcohol-free reinforcement while doing activities with friends, romantic or sexual partners, and family members. Individual ARSS-AUV items had fair-to-good test-retest reliability, while general and residual factors had excellent test-retest reliability. General alcohol reinforcement and alcohol reinforcement from friends and romantic partners were positively correlated with past-year alcohol consumption, heaviest drinking episode, and alcohol-related negative consequences. Alcohol-free reinforcement indices were unrelated to alcohol use or consequences. The ARSS-AUV appears to demonstrate good reliability and mixed concurrent validity among college student drinkers. The instrument may provide useful information about alcohol reinforcement from various activities and people and could provide clinically-relevant information for prevention and treatment programs.
Reliability analysis of composite structures
NASA Technical Reports Server (NTRS)
Kan, Han-Pin
1992-01-01
A probabilistic static stress analysis methodology has been developed to estimate the reliability of a composite structure. Closed form stress analysis methods are the primary analytical tools used in this methodology. These structural mechanics methods are used to identify independent variables whose variations significantly affect the performance of the structure. Once these variables are identified, scatter in their values is evaluated and statistically characterized. The scatter in applied loads and the structural parameters are then fitted to appropriate probabilistic distribution functions. Numerical integration techniques are applied to compute the structural reliability. The predicted reliability accounts for scatter due to variability in material strength, applied load, fabrication and assembly processes. The influence of structural geometry and mode of failure are also considerations in the evaluation. Example problems are given to illustrate various levels of analytical complexity.
Wafer level reliability for high-performance VLSI design
NASA Technical Reports Server (NTRS)
Root, Bryan J.; Seefeldt, James D.
1987-01-01
As very large scale integration architecture requires higher package density, reliability of these devices has approached a critical level. Previous processing techniques allowed a large window for varying reliability. However, as scaling and higher current densities push reliability to its limit, tighter control and instant feedback becomes critical. Several test structures developed to monitor reliability at the wafer level are described. For example, a test structure was developed to monitor metal integrity in seconds as opposed to weeks or months for conventional testing. Another structure monitors mobile ion contamination at critical steps in the process. Thus the reliability jeopardy can be assessed during fabrication preventing defective devices from ever being placed in the field. Most importantly, the reliability can be assessed on each wafer as opposed to an occasional sample.
Kübel, Christian; Voigt, Andreas; Schoenmakers, Remco; Otten, Max; Su, David; Lee, Tan-Chen; Carlsson, Anna; Bradley, John
2005-10-01
Electron tomography is a well-established technique for three-dimensional structure determination of (almost) amorphous specimens in life sciences applications. With the recent advances in nanotechnology and the semiconductor industry, there is also an increasing need for high-resolution three-dimensional (3D) structural information in physical sciences. In this article, we evaluate the capabilities and limitations of transmission electron microscopy (TEM) and high-angle-annular-dark-field scanning transmission electron microscopy (HAADF-STEM) tomography for the 3D structural characterization of partially crystalline to highly crystalline materials. Our analysis of catalysts, a hydrogen storage material, and different semiconductor devices shows that features with a diameter as small as 1-2 nm can be resolved in three dimensions by electron tomography. For partially crystalline materials with small single crystalline domains, bright-field TEM tomography provides reliable 3D structural information. HAADF-STEM tomography is more versatile and can also be used for high-resolution 3D imaging of highly crystalline materials such as semiconductor devices.
GNSS-based multi-sensor system for structural monitoring applications
NASA Astrophysics Data System (ADS)
Bogusz, Janusz; Figurski, Mariusz; Nykiel, Grzegorz; Szolucha, Marcin; Wrona, Maciej
2012-03-01
In 2007 the Centre of Applied Geomatics of the Military University of Technology started measurements aimed at the monitoring of the dynamic state of the engineering structures using GNSS. The complexity of the problem forced us to apply an integrated system architecture. This concept is based on simultaneous measuring some selected elements of the structure using various types of sensors. Measurement information from numerous instruments is numerically integrated for determining the investigated parameter, e.g., the displacement vector. The CAG team performed the tests using such a system on the two permanent 500-meters long bridges, the temporary bridge crossing for military purposes and the 300-meters high chimney of the CHP station. The information about displacement vector together with the characteristic frequencies of the structure were determined using different techniques for increasing of its reliability. This paper presents the results of such tests, gives description of the integrated system designed in the CAG and brings forward with the plans for the future.
Damage of composite structures: Detection technique, dynamic response and residual strength
NASA Astrophysics Data System (ADS)
Lestari, Wahyu
2001-10-01
Reliable and accurate health monitoring techniques can prevent catastrophic failures of structures. Conventional damage detection methods are based on visual or localized experimental methods and very often require prior information concerning the vicinity of the damage or defect. The structure must also be readily accessible for inspections. The techniques are also labor intensive. In comparison to these methods, health-monitoring techniques that are based on the structural dynamic response offers unique information on failure of structures. However, systematic relations between the experimental data and the defect are not available and frequently, the number of vibration modes needed for an accurate identification of defects is much higher than the number of modes that can be readily identified in the experiment. These motivated us to develop an experimental data based detection method with systematic relationships between the experimentally identified information and the analytical or mathematical model representing the defective structures. The developed technique use changes in vibrational curvature modes and natural frequencies. To avoid misinterpretation of the identified information, we also need to understand the effects of defects on the structural dynamic response prior to developing health-monitoring techniques. In this thesis work we focus on two type of defects in composite structures, namely delamination and edge notch like defect. Effects of nonlinearity due to the presence of defect and due to the axial stretching are studied for beams with delamination. Once defects are detected in a structure, next concern is determining the effects of the defects on the strength of the structure and its residual stiffness under dynamic loading. In this thesis, energy release rate due to dynamic loading in a delaminated structure is studied, which will be a foundation toward determining the residual strength of the structure.
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.
Probabilistic Structural Analysis Program
NASA Technical Reports Server (NTRS)
Pai, Shantaram S.; Chamis, Christos C.; Murthy, Pappu L. N.; Stefko, George L.; Riha, David S.; Thacker, Ben H.; Nagpal, Vinod K.; Mital, Subodh K.
2010-01-01
NASA/NESSUS 6.2c is a general-purpose, probabilistic analysis program that computes probability of failure and probabilistic sensitivity measures of engineered systems. Because NASA/NESSUS uses highly computationally efficient and accurate analysis techniques, probabilistic solutions can be obtained even for extremely large and complex models. Once the probabilistic response is quantified, the results can be used to support risk-informed decisions regarding reliability for safety-critical and one-of-a-kind systems, as well as for maintaining a level of quality while reducing manufacturing costs for larger-quantity products. NASA/NESSUS has been successfully applied to a diverse range of problems in aerospace, gas turbine engines, biomechanics, pipelines, defense, weaponry, and infrastructure. This program combines state-of-the-art probabilistic algorithms with general-purpose structural analysis and lifting methods to compute the probabilistic response and reliability of engineered structures. Uncertainties in load, material properties, geometry, boundary conditions, and initial conditions can be simulated. The structural analysis methods include non-linear finite-element methods, heat-transfer analysis, polymer/ceramic matrix composite analysis, monolithic (conventional metallic) materials life-prediction methodologies, boundary element methods, and user-written subroutines. Several probabilistic algorithms are available such as the advanced mean value method and the adaptive importance sampling method. NASA/NESSUS 6.2c is structured in a modular format with 15 elements.
An Energy-Based Limit State Function for Estimation of Structural Reliability in Shock Environments
Guthrie, Michael A.
2013-01-01
limit state function is developed for the estimation of structural reliability in shock environments. This limit state function uses peak modal strain energies to characterize environmental severity and modal strain energies at failure to characterize the structural capacity. The Hasofer-Lind reliability index is briefly reviewed and its computation for the energy-based limit state function is discussed. Applications to two degree of freedom mass-spring systems and to a simple finite element model are considered. For these examples, computation of the reliability index requires little effort beyond a modal analysis, but still accounts for relevant uncertainties in both the structure and environment.more » For both examples, the reliability index is observed to agree well with the results of Monte Carlo analysis. In situations where fast, qualitative comparison of several candidate designs is required, the reliability index based on the proposed limit state function provides an attractive metric which can be used to compare and control reliability.« less
Eren, Nurhan
2014-12-01
In this study, we aimed to develop two reliable and valid assessment instruments for investigating the level of difficulties mental health workers experience while working with patients with personality disorders and the attitudes they develop tt the patients. The research was carried out based on the general screening model. The study sample consisted of 332 mental health workers in several mental health clinics of Turkey, with a certain amount of experience in working with personality disorders, who were selected with a random assignment method. In order to collect data, the Personal Information Questionnaire, Difficulty of Working with Personality Disorders Scale (PD-DWS), and Attitudes Towards Patients with Personality Disorders Scale (PD-APS), which are being examined for reliability and validity, were applied. To determine construct validity, the Adjective Check List, Maslach Burnout Inventory, and State and Trait Anxiety Inventory were used. Explanatory factor analysis was used for investigating the structural validity, and Cronbach alpha, Spearman-Brown, Guttman Split-Half reliability analyses were utilized to examine the reliability. Also, item reliability and validity computations were carried out by investigating the corrected item-total correlations and discriminative indexes of the items in the scales. For the PD-DWS KMO test, the value was .946; also, a significant difference was found for the Bartlett sphericity test (p<.001). The computed test-retest coefficient reliability was .702; the Cronbach alpha value of the total test score was .952. For PD-APS KMO, the value was .925; a significant difference was found in Bartlett sphericity test (p<.001); the computed reliability coefficient based on continuity was .806; and the Cronbach alpha value of the total test score was .913. Analyses on both scales were based on total scores. It was found that PD-DWS and PD-APS have good psychometric properties, measuring the structure that is being investigated, are compatible with other scales, have high levels of internal reliability between their items, and are consistent across time. Therefore, it was concluded that both scales are valid and reliable instruments.
Weyers, Simone; Jemi, Iman; Karger, André; Raski, Bianca; Rotthoff, Thomas; Pentzek, Michael; Mortsiefer, Achim
2016-01-01
Background: Imparting communication skills has been given great importance in medical curricula. In addition to standardized assessments, students should communicate with real patients in actual clinical situations during workplace-based assessments and receive structured feedback on their performance. The aim of this project was to pilot a formative testing method for workplace-based assessment. Our investigation centered in particular on whether or not physicians view the method as feasible and how high acceptance is among students. In addition, we assessed the reliability of the method. Method: As part of the project, 16 students held two consultations each with chronically ill patients at the medical practice where they were completing GP training. These consultations were video-recorded. The trained mentoring physician rated the student’s performance and provided feedback immediately following the consultations using the Berlin Global Rating scale (BGR). Two impartial, trained raters also evaluated the videos using BGR. For qualitative and quantitative analysis, information on how physicians and students viewed feasibility and their levels of acceptance was collected in written form in a partially standardized manner. To test for reliability, the test-retest reliability was calculated for both of the overall evaluations given by each rater. The inter-rater reliability was determined for the three evaluations of each individual consultation. Results: The formative assessment method was rated positively by both physicians and students. It is relatively easy to integrate into daily routines. Its significant value lies in the personal, structured and recurring feedback. The two overall scores for each patient consultation given by the two impartial raters correlate moderately. The degree of uniformity among the three raters in respect to the individual consultations is low. Discussion: Within the scope of this pilot project, only a small sample of physicians and students could be surveyed to a limited extent. There are indications that the assessment can be improved by integrating more information on medical context and student self-assessments. Despite the current limitations regarding test criteria, it is clear that workplace-based assessment of communication skills in the clinical setting is a valuable addition to the communication curricula of medical schools. PMID:27990466
Weyers, Simone; Jemi, Iman; Karger, André; Raski, Bianca; Rotthoff, Thomas; Pentzek, Michael; Mortsiefer, Achim
2016-01-01
Background: Imparting communication skills has been given great importance in medical curricula. In addition to standardized assessments, students should communicate with real patients in actual clinical situations during workplace-based assessments and receive structured feedback on their performance. The aim of this project was to pilot a formative testing method for workplace-based assessment. Our investigation centered in particular on whether or not physicians view the method as feasible and how high acceptance is among students. In addition, we assessed the reliability of the method. Method: As part of the project, 16 students held two consultations each with chronically ill patients at the medical practice where they were completing GP training. These consultations were video-recorded. The trained mentoring physician rated the student's performance and provided feedback immediately following the consultations using the Berlin Global Rating scale (BGR). Two impartial, trained raters also evaluated the videos using BGR. For qualitative and quantitative analysis, information on how physicians and students viewed feasibility and their levels of acceptance was collected in written form in a partially standardized manner. To test for reliability, the test-retest reliability was calculated for both of the overall evaluations given by each rater. The inter-rater reliability was determined for the three evaluations of each individual consultation. Results: The formative assessment method was rated positively by both physicians and students. It is relatively easy to integrate into daily routines. Its significant value lies in the personal, structured and recurring feedback. The two overall scores for each patient consultation given by the two impartial raters correlate moderately. The degree of uniformity among the three raters in respect to the individual consultations is low. Discussion: Within the scope of this pilot project, only a small sample of physicians and students could be surveyed to a limited extent. There are indications that the assessment can be improved by integrating more information on medical context and student self-assessments. Despite the current limitations regarding test criteria, it is clear that workplace-based assessment of communication skills in the clinical setting is a valuable addition to the communication curricula of medical schools.
In-Depth View of the Structure and Growth of SnO2 Nanowires and Nanobrushes.
Stuckert, Erin P; Geiss, Roy H; Miller, Christopher J; Fisher, Ellen R
2016-08-31
Strategic application of an array of complementary imaging and diffraction techniques is critical to determine accurate structural information on nanomaterials, especially when also seeking to elucidate structure-property relationships and their effects on gas sensors. In this work, SnO2 nanowires and nanobrushes grown via chemical vapor deposition (CVD) displayed the same tetragonal SnO2 structure as revealed via powder X-ray diffraction bulk crystallinity data. Additional characterization using a range of electron microscopy imaging and diffraction techniques, however, revealed important structure and morphology distinctions between the nanomaterials. Tailoring scanning transmission electron microscopy (STEM) modes combined with transmission electron backscatter diffraction (t-EBSD) techniques afforded a more detailed view of the SnO2 nanostructures. Indeed, upon deeper analysis of individual wires and brushes, we discovered that, despite a similar bulk structure, wires and brushes grew with different crystal faces and lattice spacings. Had we not utilized multiple STEM diffraction modes in conjunction with t-EBSD, differences in orientation related to bristle density would have been overlooked. Thus, it is only through a methodical combination of several structural analysis techniques that precise structural information can be reliably obtained.
NASA Astrophysics Data System (ADS)
Kubicka, Katarzyna; Radoń, Urszula; Szaniec, Waldemar; Pawlak, Urszula
2017-10-01
The paper concerns the reliability analysis of steel structures subjected to high temperatures of fire gases. Two types of spatial structures were analysed, namely with pinned and rigid nodes. The fire analysis was carried out according to prescriptions of Eurocode. The static-strength analysis was conducted using the finite element method (FEM). The MES3D program, developed by Szaniec (Kielce University of Technology, Poland), was used for this purpose. The results received from MES3D made it possible to carry out the reliability analysis using the Numpress Explore program that was developed at the Institute of Fundamental Technological Research of the Polish Academy of Sciences [9]. The measurement of reliability of structures is the Hasofer-Lind reliability index (β). The reliability analysis was carried out according to approximation (FORM, SORM) and simulation (Importance Sampling, Monte Carlo) methods. As the fire progresses, the value of reliability index decreases. The analysis conducted for the study made it possible to evaluate the impact of node types on those changes. In real structures, it is often difficult to define correctly types of nodes, so some simplifications are made. The presented analysis contributes to the recognition of consequences of such assumptions for the safety of structures, subjected to fire.
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
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.
2009-02-17
Identification of Classified Information in Unclassified DoD Systems During the Audit of Internal Controls and Data Reliability in the Deployable...TITLE AND SUBTITLE Identification of Classified Information in Unclassified DoD Systems During the Audit of Internal Controls and Data Reliability...Systems During the Audit ofInternal Controls and Data Reliability in the Deployable Disbursing System (Report No. D-2009-054) Weare providing this
COPERNICUS - The European Union Earth Observation Programme - State of play and way ahead
NASA Astrophysics Data System (ADS)
Koch, Astrid-Christina
2015-04-01
Copernicus is the new name of the European Earth Observation Programme, GMES (Global Monitoring for Environment and Security). Copernicus or rather its predecessor was established as an EU programme. It covers all the activities for ensuring an uninterrupted provision of accurate and reliable data and information on environmental issues and security matters to users in charge of policy making, implementation and monitoring, in the EU and its Member States. Copernicus aims at providing Europe with a continuous, independent and reliable access to observation data and information. The EU investment aims at filling the observation gaps, providing access to existing assets and developing operational services. The data policy of the Copernicus programme supports an open, full and free of charge data access that is in line with the data sharing principles of the Group for Earth Observation (GEO). Copernicus is structured in six Services: Marine, Atmosphere, Land and Climate change monitoring as well as support to Emergency and Security. Copernicus uses data from satellites and in-situ sensors such as buoys, balloons or air sensors to provide timely and reliable added-value information and forecasting to support for example, agriculture and fisheries, land use and urban planning, the fight against forest fires, disaster response, maritime transport or air pollution monitoring. The need for continuing such observations is becoming critical, considering the increasing political pressure on public authorities to take informed decisions in the field of environment, security and climate change and the need to respect international agreements. Copernicus also contributes to economic stability and growth by boosting commercial applications (the so-called downstream services) in many different sectors through a full and open access to Copernicus observation data and information products. KEY WORDS: Sentinels, big data, data access, Emergency, Marine, Atmosphere.
Hotchkiss, David R; Aqil, Anwer; Lippeveld, Theo; Mukooyo, Edward
2010-07-03
Sound policy, resource allocation and day-to-day management decisions in the health sector require timely information from routine health information systems (RHIS). In most low- and middle-income countries, the RHIS is viewed as being inadequate in providing quality data and continuous information that can be used to help improve health system performance. In addition, there is limited evidence on the effectiveness of RHIS strengthening interventions in improving data quality and use. The purpose of this study is to evaluate the usefulness of the newly developed Performance of Routine Information System Management (PRISM) framework, which consists of a conceptual framework and associated data collection and analysis tools to assess, design, strengthen and evaluate RHIS. The specific objectives of the study are: a) to assess the reliability and validity of the PRISM instruments and b) to assess the validity of the PRISM conceptual framework. Facility- and worker-level data were collected from 110 health care facilities in twelve districts in Uganda in 2004 and 2007 using records reviews, structured interviews and self-administered questionnaires. The analysis procedures include Cronbach's alpha to assess internal consistency of selected instruments, test-retest analysis to assess the reliability and sensitivity of the instruments, and bivariate and multivariate statistical techniques to assess validity of the PRISM instruments and conceptual framework. Cronbach's alpha analysis suggests high reliability (0.7 or greater) for the indices measuring a promotion of a culture of information, RHIS tasks self-efficacy and motivation. The study results also suggest that a promotion of a culture of information influences RHIS tasks self-efficacy, RHIS tasks competence and motivation, and that self-efficacy and the presence of RHIS staff have a direct influence on the use of RHIS information, a key aspect of RHIS performance. The study results provide some empirical support for the reliability and validity of the PRISM instruments and the validity of the PRISM conceptual framework, suggesting that the PRISM approach can be effectively used by RHIS policy makers and practitioners to assess the RHIS and evaluate RHIS strengthening interventions. However, additional studies with larger sample sizes are needed to further investigate the value of the PRISM instruments in exploring the linkages between RHIS data quality and use, and health systems performance.
CERTS: Consortium for Electric Reliability Technology Solutions - Research Highlights
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eto, Joseph
2003-07-30
Historically, the U.S. electric power industry was vertically integrated, and utilities were responsible for system planning, operations, and reliability management. As the nation moves to a competitive market structure, these functions have been disaggregated, and no single entity is responsible for reliability management. As a result, new tools, technologies, systems, and management processes are needed to manage the reliability of the electricity grid. However, a number of simultaneous trends prevent electricity market participants from pursuing development of these reliability tools: utilities are preoccupied with restructuring their businesses, research funding has declined, and the formation of Independent System Operators (ISOs) andmore » Regional Transmission Organizations (RTOs) to operate the grid means that control of transmission assets is separate from ownership of these assets; at the same time, business uncertainty, and changing regulatory policies have created a climate in which needed investment for transmission infrastructure and tools for reliability management has dried up. To address the resulting emerging gaps in reliability R&D, CERTS has undertaken much-needed public interest research on reliability technologies for the electricity grid. CERTS' vision is to: (1) Transform the electricity grid into an intelligent network that can sense and respond automatically to changing flows of power and emerging problems; (2) Enhance reliability management through market mechanisms, including transparency of real-time information on the status of the grid; (3) Empower customers to manage their energy use and reliability needs in response to real-time market price signals; and (4) Seamlessly integrate distributed technologies--including those for generation, storage, controls, and communications--to support the reliability needs of both the grid and individual customers.« less
Evaluation of the Transit Reliability Information Program
DOT National Transportation Integrated Search
1982-06-01
This report presents an evaluation of the rail portion of the Transit Reliability Information Program (TRIP), which was designed to collect and analyze equipment reliability data on U.S. transit systems. This assessment was conducted at the end of it...
Development of a probabilistic analysis methodology for structural reliability estimation
NASA Technical Reports Server (NTRS)
Torng, T. Y.; Wu, Y.-T.
1991-01-01
The novel probabilistic analysis method for assessment of structural reliability presented, which combines fast-convolution with an efficient structural reliability analysis, can after identifying the most important point of a limit state proceed to establish a quadratic-performance function. It then transforms the quadratic function into a linear one, and applies fast convolution. The method is applicable to problems requiring computer-intensive structural analysis. Five illustrative examples of the method's application are given.
1982-11-22
RD-Ri42 354 APPLICATION OF ADVANCED FRACTURE MECHANICS TECHNOLOGY i/i TT ENSURE STRUCTURA..(U) 1WESTINGHOUSE RESEARCH FND DEVELOPMENT CENTER...I Iml .4. 47 Igo 12. 4 %B 1. __ ~. ~% ski Z L __ 12 APPLICATION OF ADVANCED FRACTURE MECHANICS -p TECHNOLOGY TO ENSURE STRUCTURAL RELIABILITY IN...Road W Pilttsburgh. Pennsylvania 15235 84 06 18 207 APPLICATION OF ADVANCED FRACTURE MECHANICS TECHNOLOGY TO ENSURE STRUCTURAL RELIABILITY IN CRITICAL
Quality assessment of protein model-structures using evolutionary conservation.
Kalman, Matan; Ben-Tal, Nir
2010-05-15
Programs that evaluate the quality of a protein structural model are important both for validating the structure determination procedure and for guiding the model-building process. Such programs are based on properties of native structures that are generally not expected for faulty models. One such property, which is rarely used for automatic structure quality assessment, is the tendency for conserved residues to be located at the structural core and for variable residues to be located at the surface. We present ConQuass, a novel quality assessment program based on the consistency between the model structure and the protein's conservation pattern. We show that it can identify problematic structural models, and that the scores it assigns to the server models in CASP8 correlate with the similarity of the models to the native structure. We also show that when the conservation information is reliable, the method's performance is comparable and complementary to that of the other single-structure quality assessment methods that participated in CASP8 and that do not use additional structural information from homologs. A perl implementation of the method, as well as the various perl and R scripts used for the analysis are available at http://bental.tau.ac.il/ConQuass/. nirb@tauex.tau.ac.il Supplementary data are available at Bioinformatics online.
Multiple objective optimization in reliability demonstration test
Lu, Lu; Anderson-Cook, Christine Michaela; Li, Mingyang
2016-10-01
Reliability demonstration tests are usually performed in product design or validation processes to demonstrate whether a product meets specified requirements on reliability. For binomial demonstration tests, the zero-failure test has been most commonly used due to its simplicity and use of minimum sample size to achieve an acceptable consumer’s risk level. However, this test can often result in unacceptably high risk for producers as well as a low probability of passing the test even when the product has good reliability. This paper explicitly explores the interrelationship between multiple objectives that are commonly of interest when planning a demonstration test andmore » proposes structured decision-making procedures using a Pareto front approach for selecting an optimal test plan based on simultaneously balancing multiple criteria. Different strategies are suggested for scenarios with different user priorities and graphical tools are developed to help quantify the trade-offs between choices and to facilitate informed decision making. As a result, potential impacts of some subjective user inputs on the final decision are studied to offer insights and useful guidance for general applications.« less
Problems and Processes in Medical Encounters: The CASES method of dialogue analysis
Laws, M. Barton; Taubin, Tatiana; Bezreh, Tanya; Lee, Yoojin; Beach, Mary Catherine; Wilson, Ira B.
2013-01-01
Objective To develop methods to reliably capture structural and dynamic temporal features of clinical interactions. Methods Observational study of 50 audio-recorded routine outpatient visits to HIV specialty clinics, using innovative analytic methods. The Comprehensive Analysis of the Structure of Encounters System (CASES) uses transcripts coded for speech acts, then imposes larger-scale structural elements: threads – the problems or issues addressed; and processes within threads –basic tasks of clinical care labeled Presentation, Information, Resolution (decision making) and Engagement (interpersonal exchange). Threads are also coded for the nature of resolution. Results 61% of utterances are in presentation processes. Provider verbal dominance is greatest in information and resolution processes, which also contain a high proportion of provider directives. About half of threads result in no action or decision. Information flows predominantly from patient to provider in presentation processes, and from provider to patient in information processes. Engagement is rare. Conclusions In this data, resolution is provider centered; more time for patient participation in resolution, or interpersonal engagement, would have to come from presentation. Practice Implications Awareness of the use of time in clinical encounters, and the interaction processes associated with various tasks, may help make clinical communication more efficient and effective. PMID:23391684
Problems and processes in medical encounters: the cases method of dialogue analysis.
Laws, M Barton; Taubin, Tatiana; Bezreh, Tanya; Lee, Yoojin; Beach, Mary Catherine; Wilson, Ira B
2013-05-01
To develop methods to reliably capture structural and dynamic temporal features of clinical interactions. Observational study of 50 audio-recorded routine outpatient visits to HIV specialty clinics, using innovative analytic methods. The comprehensive analysis of the structure of encounters system (CASES) uses transcripts coded for speech acts, then imposes larger-scale structural elements: threads--the problems or issues addressed; and processes within threads--basic tasks of clinical care labeled presentation, information, resolution (decision making) and Engagement (interpersonal exchange). Threads are also coded for the nature of resolution. 61% of utterances are in presentation processes. Provider verbal dominance is greatest in information and resolution processes, which also contain a high proportion of provider directives. About half of threads result in no action or decision. Information flows predominantly from patient to provider in presentation processes, and from provider to patient in information processes. Engagement is rare. In this data, resolution is provider centered; more time for patient participation in resolution, or interpersonal engagement, would have to come from presentation. Awareness of the use of time in clinical encounters, and the interaction processes associated with various tasks, may help make clinical communication more efficient and effective. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Mass Media Theory, Leveraging Relationships, and Reliable Strategic Communication Effects
2008-03-19
other people who are in the same social and cultural groups. Families respond to patriarchs and matriarchs , congregations respond to pastors, and teens...media to self-correct behavior in order to make society seem more “normal.” Verbal and Written Message- Centric Theories Premise of Theory Magic...Effects Harmony and Balance People gravitate toward information they already believe. Structural Functionalism When society begins to seem
NASA Astrophysics Data System (ADS)
Ottoni, F.; Freddi, F.; Zerbi, A.
2017-05-01
It's well known that more and more accurate methodologies and automatic tools are now available in the field of geometric survey and image processing and they constitute a fundamental instrument for cultural heritage knowledge and preservation; on the other side, very smart and precise numerical models are continuously improved and used in order to simulate the mechanical behaviour of masonry structures: both instruments and technologies are important part of a global process of knowledge which is at the base of any conservation project of cultural heritage. Despite the high accuracy and automation level reached by both technologies and programs, the transfer of data between them is not an easy task and defining the most reliable way to translate and exchange information without data loosing is still an open issue. The goal of the present paper is to analyse the complex process of translation from the very precise (and sometimes redundant) information obtainable by the modern survey methodologies for historic buildings (as laser scanner), into the very simplified (may be too much) schemes used to understand their real structural behaviour, with the final aim to contribute to the discussion on reliable methods for cultural heritage knowledge improvement, through empiricism.
High-rate RTK and PPP multi-GNSS positioning for small-scale dynamic displacements monitoring
NASA Astrophysics Data System (ADS)
Paziewski, Jacek; Sieradzki, Rafał; Baryła, Radosław; Wielgosz, Pawel
2017-04-01
The monitoring of dynamic displacements and deformations of engineering structures such as buildings, towers and bridges is of great interest due to several practical and theoretical reasons. The most important is to provide information required for safe maintenance of the constructions. High temporal resolution and precision of GNSS observations predestine this technology to be applied to most demanding application in terms of accuracy, availability and reliability. GNSS technique supported by appropriate processing methodology may meet the specific demands and requirements of ground and structures monitoring. Thus, high-rate multi-GNSS signals may be used as reliable source of information on dynamic displacements of ground and engineering structures, also in real time applications. In this study we present initial results of application of precise relative GNSS positioning for detection of small scale (cm level) high temporal resolution dynamic displacements. Methodology and algorithms applied in self-developed software allowing for relative positioning using high-rate dual-frequency phase and pseudorange GPS+Galileo observations are also given. Additionally, an approach was also made to use the Precise Point Positioning technique to such application. In the experiment were used the observations obtained from high-rate (20 Hz) geodetic receivers. The dynamic displacements were simulated using specially constructed device moving GNSS antenna with dedicated amplitude and frequency. The obtained results indicate on possibility of detection of dynamic displacements of the GNSS antenna even at the level of few millimetres using both relative and Precise Point Positioning techniques after suitable signals processing.
Automated image segmentation using support vector machines
NASA Astrophysics Data System (ADS)
Powell, Stephanie; Magnotta, Vincent A.; Andreasen, Nancy C.
2007-03-01
Neurodegenerative and neurodevelopmental diseases demonstrate problems associated with brain maturation and aging. Automated methods to delineate brain structures of interest are required to analyze large amounts of imaging data like that being collected in several on going multi-center studies. We have previously reported on using artificial neural networks (ANN) to define subcortical brain structures including the thalamus (0.88), caudate (0.85) and the putamen (0.81). In this work, apriori probability information was generated using Thirion's demons registration algorithm. The input vector consisted of apriori probability, spherical coordinates, and an iris of surrounding signal intensity values. We have applied the support vector machine (SVM) machine learning algorithm to automatically segment subcortical and cerebellar regions using the same input vector information. SVM architecture was derived from the ANN framework. Training was completed using a radial-basis function kernel with gamma equal to 5.5. Training was performed using 15,000 vectors collected from 15 training images in approximately 10 minutes. The resulting support vectors were applied to delineate 10 images not part of the training set. Relative overlap calculated for the subcortical structures was 0.87 for the thalamus, 0.84 for the caudate, 0.84 for the putamen, and 0.72 for the hippocampus. Relative overlap for the cerebellar lobes ranged from 0.76 to 0.86. The reliability of the SVM based algorithm was similar to the inter-rater reliability between manual raters and can be achieved without rater intervention.
Problem of unity of measurements in ensuring safety of hydraulic structures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kheifits, V.Z.; Markov, A.I.; Braitsev, V.V.
1994-07-01
Ensuring the safety of hydraulic structures (HSs) is not only an industry but also a national and global concern, since failure of large water impounding structures can entail large losses of lives and enormous material losses related to destruction downstream. The main information on the degree of safety of a structure is obtained by comparing information about the actual state of the structure obtained on the basis of measurements in key zones of the structure with the predicted state on basis of the design model used when designing the structure for given conditions of external actions. Numerous, from hundreds tomore » thousands, string type transducers are placed in large HSs. This system of transducers monitor the stress-strain rate, seepage, and thermal regimes. These measurements are supported by the State Standards Committee which certifies the accuracy of the checking methods. To improve the instrumental monitoring of HSs, the author recommends: Calibration of methods and means of reliable diagnosis for each measuring channel in the HS, improvements to reduce measurement error, support for the system software programs, and development of appropriate standards for the design and examination of HSs.« less
Extracting the Textual and Temporal Structure of Supercomputing Logs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jain, S; Singh, I; Chandra, A
2009-05-26
Supercomputers are prone to frequent faults that adversely affect their performance, reliability and functionality. System logs collected on these systems are a valuable resource of information about their operational status and health. However, their massive size, complexity, and lack of standard format makes it difficult to automatically extract information that can be used to improve system management. In this work we propose a novel method to succinctly represent the contents of supercomputing logs, by using textual clustering to automatically find the syntactic structures of log messages. This information is used to automatically classify messages into semantic groups via an onlinemore » clustering algorithm. Further, we describe a methodology for using the temporal proximity between groups of log messages to identify correlated events in the system. We apply our proposed methods to two large, publicly available supercomputing logs and show that our technique features nearly perfect accuracy for online log-classification and extracts meaningful structural and temporal message patterns that can be used to improve the accuracy of other log analysis techniques.« less
NASA Astrophysics Data System (ADS)
Yu, Bo; Ning, Chao-lie; Li, Bing
2017-03-01
A probabilistic framework for durability assessment of concrete structures in marine environments was proposed in terms of reliability and sensitivity analysis, which takes into account the uncertainties under the environmental, material, structural and executional conditions. A time-dependent probabilistic model of chloride ingress was established first to consider the variations in various governing parameters, such as the chloride concentration, chloride diffusion coefficient, and age factor. Then the Nataf transformation was adopted to transform the non-normal random variables from the original physical space into the independent standard Normal space. After that the durability limit state function and its gradient vector with respect to the original physical parameters were derived analytically, based on which the first-order reliability method was adopted to analyze the time-dependent reliability and parametric sensitivity of concrete structures in marine environments. The accuracy of the proposed method was verified by comparing with the second-order reliability method and the Monte Carlo simulation. Finally, the influences of environmental conditions, material properties, structural parameters and execution conditions on the time-dependent reliability of concrete structures in marine environments were also investigated. The proposed probabilistic framework can be implemented in the decision-making algorithm for the maintenance and repair of deteriorating concrete structures in marine environments.
A reliability analysis of the revised competitiveness index.
Harris, Paul B; Houston, John M
2010-06-01
This study examined the reliability of the Revised Competitiveness Index by investigating the test-retest reliability, interitem reliability, and factor structure of the measure based on a sample of 280 undergraduates (200 women, 80 men) ranging in age from 18 to 28 years (M = 20.1, SD = 2.1). The findings indicate that the Revised Competitiveness Index has high test-retest reliability, high inter-item reliability, and a stable factor structure. The results support the assertion that the Revised Competitiveness Index assesses competitiveness as a stable trait rather than a dynamic state.
Novel cost controlled materials and processing for primary structures
NASA Technical Reports Server (NTRS)
Dastin, S. J.
1993-01-01
Textile laminates, developed a number of years ago, have recently been shown to be applicable to primary aircraft structures for both small and large components. Such structures have the potential to reduce acquisition costs but require advanced automated processing to keep costs controlled while verifying product reliability and assuring structural integrity, durability and affordable life-cycle costs. Recently, resin systems and graphite-reinforced woven shapes have been developed that have the potential for improved RTM processes for aircraft structures. Ciba-Geigy, Brochier Division has registered an RTM prepreg reinforcement called 'Injectex' that has shown effectivity for aircraft components. Other novel approaches discussed are thermotropic resins producing components by injection molding and ceramic polymers for long-duration hot structures. The potential of such materials and processing will be reviewed along with initial information/data available to date.
Barcoding Human Physical Activity to Assess Chronic Pain Conditions
Paraschiv-Ionescu, Anisoara; Perruchoud, Christophe; Buchser, Eric; Aminian, Kamiar
2012-01-01
Background Modern theories define chronic pain as a multidimensional experience – the result of complex interplay between physiological and psychological factors with significant impact on patients' physical, emotional and social functioning. The development of reliable assessment tools capable of capturing the multidimensional impact of chronic pain has challenged the medical community for decades. A number of validated tools are currently used in clinical practice however they all rely on self-reporting and are therefore inherently subjective. In this study we show that a comprehensive analysis of physical activity (PA) under real life conditions may capture behavioral aspects that may reflect physical and emotional functioning. Methodology PA was monitored during five consecutive days in 60 chronic pain patients and 15 pain-free healthy subjects. To analyze the various aspects of pain-related activity behaviors we defined the concept of PA ‘barcoding’. The main idea was to combine different features of PA (type, intensity, duration) to define various PA states. The temporal sequence of different states was visualized as a ‘barcode’ which indicated that significant information about daily activity can be contained in the amount and variety of PA states, and in the temporal structure of sequence. This information was quantified using complementary measures such as structural complexity metrics (information and sample entropy, Lempel-Ziv complexity), time spent in PA states, and two composite scores, which integrate all measures. The reliability of these measures to characterize chronic pain conditions was assessed by comparing groups of subjects with clinically different pain intensity. Conclusion The defined measures of PA showed good discriminative features. The results suggest that significant information about pain-related functional limitations is captured by the structural complexity of PA barcodes, which decreases when the intensity of pain increases. We conclude that a comprehensive analysis of daily-life PA can provide an objective appraisal of the intensity of pain. PMID:22384191
Recent developments in the structural design and optimization of ITER neutral beam manifold
NASA Astrophysics Data System (ADS)
Chengzhi, CAO; Yudong, PAN; Zhiwei, XIA; Bo, LI; Tao, JIANG; Wei, LI
2018-02-01
This paper describes a new design of the neutral beam manifold based on a more optimized support system. A proposed alternative scheme has presented to replace the former complex manifold supports and internal pipe supports in the final design phase. Both the structural reliability and feasibility were confirmed with detailed analyses. Comparative analyses between two typical types of manifold support scheme were performed. All relevant results of mechanical analyses for typical operation scenarios and fault conditions are presented. Future optimization activities are described, which will give useful information for a refined setting of components in the next phase.
MEMS Reliability Assurance Activities at JPL
NASA Technical Reports Server (NTRS)
Kayali, S.; Lawton, R.; Stark, B.
2000-01-01
An overview of Microelectromechanical Systems (MEMS) reliability assurance and qualification activities at JPL is presented along with the a discussion of characterization of MEMS structures implemented on single crystal silicon, polycrystalline silicon, CMOS, and LIGA processes. Additionally, common failure modes and mechanisms affecting MEMS structures, including radiation effects, are discussed. Common reliability and qualification practices contained in the MEMS Reliability Assurance Guideline are also presented.
Young Women’s Perspectives of Their Adolescent Treatment Programs: A Qualitative Study
Clark, Miriam; Buchanan, Rohanna
2018-01-01
The perspectives of at-risk adolescent clients can play an important role in informing treatment services. The current study examines qualitative interview data from 15 young women with histories of maltreatment. Using a semi-structured qualitative interview approach, we asked the women to think retrospectively about their treatment experiences as adolescent girls. Results highlight the need for providing adolescent girls with reliable and practical information about risky sexual behavior and drug use from relatable and trustworthy helping professionals. We discuss strategies for developing and maintaining trust and delivering specific content. PMID:29470424
Implication of Broadband Dispersion Measurements in Constraining Upper Mantle Velocity Structures
NASA Astrophysics Data System (ADS)
Kuponiyi, A.; Kao, H.; Cassidy, J. F.; Darbyshire, F. A.; Dosso, S. E.; Gosselin, J. M.; Spence, G.
2017-12-01
Dispersion measurements from earthquake (EQ) data are traditionally inverted to obtain 1-D shear-wave velocity models, which provide information on deep earth structures. However, in many cases, EQ-derived dispersion measurements lack short-period information, which theoretically should provide details of shallow structures. We show that in at least some cases short-period information, such as can be obtained from ambient seismic noise (ASN) processing, must be combined with EQ dispersion measurements to properly constrain deeper (e.g. upper-mantle) structures. To verify this, synthetic dispersion data are generated using hypothetical velocity models under four scenarios: EQ only (with and without deep low-velocity layers) and combined EQ and ASN data (with and without deep low-velocity layers). The now "broadband" dispersion data are inverted using a trans-dimensional Bayesian framework with the aim of recovering the initial velocity models and assessing uncertainties. Our results show that the deep low-velocity layer could only be recovered from the inversion of the combined ASN-EQ dispersion measurements. Given this result, we proceed to describe a method for obtaining reliable broadband dispersion measurements from both ASN and EQ and show examples for real data. The implication of this study in the characterization of lithospheric and upper mantle structures, such as the Lithosphere-Asthenosphere Boundary (LAB), is also discussed.
Lenderking, William R; Wyrwich, Kathleen W; Stolar, Marilyn; Howard, Kellee A; Leibman, Chris; Buchanan, Jacqui; Lacey, Loretto; Kopp, Zoe; Stern, Yaakov
2013-12-01
The Dependence Scale (DS) was designed to measure dependence on others among patients with Alzheimer's disease (AD). The objectives of this research were primarily to strengthen the psychometric evidence for the use of the DS in AD studies. Patients with mild to moderately severe AD were examined in 3 study databases. Within each data set, internal consistency, validity, and responsiveness were examined, and structural equation models were fit. The DS has strong psychometric properties. The DS scores differed significantly across known groups and demonstrated moderate to strong correlations with measures hypothesized to be related to dependence (|r| ≥ .31). Structural equation modeling supported the validity of the DS concept. An anchor-based DS responder definition to interpret a treatment benefit over time was identified. The DS is a reliable, valid, and interpretable measure of dependence associated with AD and is shown to be related to--but provides information distinct from--cognition, functioning, and behavior.
Framework for SEM contour analysis
NASA Astrophysics Data System (ADS)
Schneider, L.; Farys, V.; Serret, E.; Fenouillet-Beranger, C.
2017-03-01
SEM images provide valuable information about patterning capability. Geometrical properties such as Critical Dimension (CD) can be extracted from them and are used to calibrate OPC models, thus making OPC more robust and reliable. However, there is currently a shortage of appropriate metrology tools to inspect complex two-dimensional patterns in the same way as one would work with simple one-dimensional patterns. In this article we present a full framework for the analysis of SEM images. It has been proven to be fast, reliable and robust for every type of structure, and particularly for two-dimensional structures. To achieve this result, several innovative solutions have been developed and will be presented in the following pages. Firstly, we will present a new noise filter which is used to reduce noise on SEM images, followed by an efficient topography identifier, and finally we will describe the use of a topological skeleton as a measurement tool that can extend CD measurements on all kinds of patterns.
The Reliability of Psychiatric Diagnosis Revisited
Rankin, Eric; France, Cheryl; El-Missiry, Ahmed; John, Collin
2006-01-01
Background: The authors reviewed the topic of reliability of psychiatric diagnosis from the turn of the 20th century to present. The objectives of this paper are to explore the reasons of unreliability of psychiatric diagnosis and propose ways to improve the reliability of psychiatric diagnosis. Method: The authors reviewed the literature on the concept of reliability of psychiatric diagnosis with emphasis on the impact of interviewing skills, use of diagnostic criteria, and structured interviews on the reliability of psychiatric diagnosis. Results: Causes of diagnostic unreliability are attributed to the patient, the clinician and psychiatric nomenclature. The reliability of psychiatric diagnosis can be enhanced by using diagnostic criteria, defining psychiatric symptoms and structuring the interviews. Conclusions: The authors propose the acronym ‘DR.SED,' which stands for diagnostic criteria, reference definitions, structuring the interview, clinical experience, and data. The authors recommend that clinicians use the DR.SED paradigm to improve the reliability of psychiatric diagnoses. PMID:21103149
Analysis of whisker-toughened CMC structural components using an interactive reliability model
NASA Technical Reports Server (NTRS)
Duffy, Stephen F.; Palko, Joseph L.
1992-01-01
Realizing wider utilization of ceramic matrix composites (CMC) requires the development of advanced structural analysis technologies. This article focuses on the use of interactive reliability models to predict component probability of failure. The deterministic William-Warnke failure criterion serves as theoretical basis for the reliability model presented here. The model has been implemented into a test-bed software program. This computer program has been coupled to a general-purpose finite element program. A simple structural problem is presented to illustrate the reliability model and the computer algorithm.
On the design of high-rise buildings with a specified level of reliability
NASA Astrophysics Data System (ADS)
Dolganov, Andrey; Kagan, Pavel
2018-03-01
High-rise buildings have a specificity, which significantly distinguishes them from traditional buildings of high-rise and multi-storey buildings. Steel structures in high-rise buildings are advisable to be used in earthquake-proof regions, since steel, due to its plasticity, provides damping of the kinetic energy of seismic impacts. These aspects should be taken into account when choosing a structural scheme of a high-rise building and designing load-bearing structures. Currently, modern regulatory documents do not quantify the reliability of structures. Although the problem of assigning an optimal level of reliability has existed for a long time. The article shows the possibility of designing metal structures of high-rise buildings with specified reliability. Currently, modern regulatory documents do not quantify the reliability of high-rise buildings. Although the problem of assigning an optimal level of reliability has existed for a long time. It is proposed to establish the value of reliability 0.99865 (3σ) for constructions of buildings and structures of a normal level of responsibility in calculations for the first group of limiting states. For increased (construction of high-rise buildings) and reduced levels of responsibility for the provision of load-bearing capacity, it is proposed to assign respectively 0.99997 (4σ) and 0.97725 (2σ). The coefficients of the use of the cross section of a metal beam for different levels of security are given.
Reddy, Linda A; Dudek, Christopher M; Fabiano, Gregory A; Peters, Stephanie
2015-12-01
This article presents information about the construct validity and reliability of a new teacher self-report measure of classroom instructional and behavioral practices (the Classroom Strategies Scales-Teacher Form; CSS-T). The theoretical underpinnings and empirical basis for the instructional and behavioral management scales are presented. Information is provided about the construct validity, internal consistency, test-retest reliability, and freedom from item-bias of the scales. Given previous investigations with the CSS Observer Form, it was hypothesized that internal consistency would be adequate and that confirmatory factor analyses (CFA) of CSS-T data from 293 classrooms would offer empirical support for the CSS-T's Total, Composite and subscales, and yield a similar factor structure to that of the CSS Observer Form. Goodness-of-fit indices of χ2/df, Root Mean Square Error of Approximation, Goodness of Fit Index, and Adjusted Goodness of Fit Index suggested satisfactory fit of proposed CFA models whereas the Comparative Fit Index did not. Internal consistency estimates of .93 and .94 were obtained for the Instructional Strategies and Behavioral Strategies Total scales respectively. Adequate test-retest reliability was found for instructional and behavioral total scales (r = .79, r = .84, percent agreement 93% and 93%). The CSS-T evidences freedom from item bias on important teacher demographics (age, educational degree, and years of teaching experience). Implications of results are discussed. (c) 2015 APA, all rights reserved).
System Analysis by Mapping a Fault-tree into a Bayesian-network
NASA Astrophysics Data System (ADS)
Sheng, B.; Deng, C.; Wang, Y. H.; Tang, L. H.
2018-05-01
In view of the limitations of fault tree analysis in reliability assessment, Bayesian Network (BN) has been studied as an alternative technology. After a brief introduction to the method for mapping a Fault Tree (FT) into an equivalent BN, equations used to calculate the structure importance degree, the probability importance degree and the critical importance degree are presented. Furthermore, the correctness of these equations is proved mathematically. Combining with an aircraft landing gear’s FT, an equivalent BN is developed and analysed. The results show that richer and more accurate information have been achieved through the BN method than the FT, which demonstrates that the BN is a superior technique in both reliability assessment and fault diagnosis.
Seçkin, Gül; Yeatts, Dale; Hughes, Susan; Hudson, Cassie; Bell, Valarie
2016-07-11
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. 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. 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 and the subsample (age ≥ 60 years). Linear regression analyses were performed in separate models to examine: (1) the construct validity of the e-HLS and (2) its association with respondents' demographic characteristics and health variables. The EFA produced a 3-factor solution: communication (2 items), trust (4 items), and action (13 items). The 3-factor structure of the e-HLS was found to be invariant for the subsample. Fit indices obtained were as follows: full sample: χ(2) (710)=698.547, df=131, P<.001, comparative fit index (CFI)=0.94, normed fit index (NFI)=0.92, root mean squared error of approximation (RMSEA)=0.08; and for the older subsample (age ≥ 60 years): χ(2) (194)=275.744, df=131, P<.001, CFI=0.95, NFI=0.90, RMSEA=0.08. The analyses supported the e-HLS validity and internal reliability for the full sample and subsample. The overwhelming majority of our respondents reported a great deal of confidence in their ability to appraise the quality of information obtained from the Internet, yet less than half reported performing quality checks contained on the e-HLS.
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 and the subsample (age ≥ 60 years). Linear regression analyses were performed in separate models to examine: (1) the construct validity of the e-HLS and (2) its association with respondents’ demographic characteristics and health variables. Results The EFA produced a 3-factor solution: communication (2 items), trust (4 items), and action (13 items). The 3-factor structure of the e-HLS was found to be invariant for the subsample. Fit indices obtained were as follows: full sample: χ2 (710)=698.547, df=131, P<.001, comparative fit index (CFI)=0.94, normed fit index (NFI)=0.92, root mean squared error of approximation (RMSEA)=0.08; and for the older subsample (age ≥ 60 years): χ2 (194)=275.744, df=131, P<.001, CFI=0.95, NFI=0.90, RMSEA=0.08. Conclusions The analyses supported the e-HLS validity and internal reliability for the full sample and subsample. The overwhelming majority of our respondents reported a great deal of confidence in their ability to appraise the quality of information obtained from the Internet, yet less than half reported performing quality checks contained on the e-HLS. PMID:27400726
Advances in Micromechanics Modeling of Composites Structures for Structural Health Monitoring
NASA Astrophysics Data System (ADS)
Moncada, Albert
Although high performance, light-weight composites are increasingly being used in applications ranging from aircraft, rotorcraft, weapon systems and ground vehicles, the assurance of structural reliability remains a critical issue. In composites, damage is absorbed through various fracture processes, including fiber failure, matrix cracking and delamination. An important element in achieving reliable composite systems is a strong capability of assessing and inspecting physical damage of critical structural components. Installation of a robust Structural Health Monitoring (SHM) system would be very valuable in detecting the onset of composite failure. A number of major issues still require serious attention in connection with the research and development aspects of sensor-integrated reliable SHM systems for composite structures. In particular, the sensitivity of currently available sensor systems does not allow detection of micro level damage; this limits the capability of data driven SHM systems. As a fundamental layer in SHM, modeling can provide in-depth information on material and structural behavior for sensing and detection, as well as data for learning algorithms. This dissertation focuses on the development of a multiscale analysis framework, which is used to detect various forms of damage in complex composite structures. A generalized method of cells based micromechanics analysis, as implemented in NASA's MAC/GMC code, is used for the micro-level analysis. First, a baseline study of MAC/GMC is performed to determine the governing failure theories that best capture the damage progression. The deficiencies associated with various layups and loading conditions are addressed. In most micromechanics analysis, a representative unit cell (RUC) with a common fiber packing arrangement is used. The effect of variation in this arrangement within the RUC has been studied and results indicate this variation influences the macro-scale effective material properties and failure stresses. The developed model has been used to simulate impact damage in a composite beam and an airfoil structure. The model data was verified through active interrogation using piezoelectric sensors. The multiscale model was further extended to develop a coupled damage and wave attenuation model, which was used to study different damage states such as fiber-matrix debonding in composite structures with surface bonded piezoelectric sensors.
NASA Astrophysics Data System (ADS)
Kurnosov, R. Yu; Chernyshova, T. I.; Chernyshov, V. N.
2018-05-01
The algorithms for improving the metrological reliability of analogue blocks of measuring channels and information-measuring systems are developed. The proposed algorithms ensure the optimum values of their metrological reliability indices for a given analogue circuit block solution.
Structural system reliability calculation using a probabilistic fault tree analysis method
NASA Technical Reports Server (NTRS)
Torng, T. Y.; Wu, Y.-T.; Millwater, H. R.
1992-01-01
The development of a new probabilistic fault tree analysis (PFTA) method for calculating structural system reliability is summarized. The proposed PFTA procedure includes: developing a fault tree to represent the complex structural system, constructing an approximation function for each bottom event, determining a dominant sampling sequence for all bottom events, and calculating the system reliability using an adaptive importance sampling method. PFTA is suitable for complicated structural problems that require computer-intensive computer calculations. A computer program has been developed to implement the PFTA.
Internal consistency and stability of the CANTAB neuropsychological test battery in children.
Syväoja, Heidi J; Tammelin, Tuija H; Ahonen, Timo; Räsänen, Pekka; Tolvanen, Asko; Kankaanpää, Anna; Kantomaa, Marko T
2015-06-01
The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a computer-assessed test battery widely use in different populations. The internal consistency and 1-year stability of CANTAB tests were examined in school-age children. Two hundred-thirty children (57% girls) from five schools in the Jyväskylä school district in Finland participated in the study in spring 2011. The children completed the following CANTAB tests: (a) visual memory (pattern recognition memory [PRM] and spatial recognition memory [SRM]), (b) executive function (spatial span [SSP], Stockings of Cambridge [SOC], and intra-extra dimensional set shift [IED]), and (c) attention (reaction time [RTI] and rapid visual information processing [RVP]). Seventy-four children participated in the follow-up measurements (64% girls) in spring 2012. Cronbach's alpha reliability coefficient was used to estimate the internal consistency of the nonhampering test, and structural equation models were applied to examine the stability of these tests. The reliability and the stability could not be determined for IED or SSP because of the nature of these tests. The internal consistency was acceptable only in the RTI task. The 1-year stability was moderate-to-good for the PRM, RTI, and RVP. The SSP and IED showed a moderate correlation between the two measurement points. The SRM and the SOC tasks were not reliable or stable measures in this study population. For research purposes, we recommend using structural equation modeling to improve reliability. The results suggest that the reliability and the stability of computer-based test batteries should be confirmed in the target population before using them for clinical or research purposes. (c) 2015 APA, all rights reserved).
[An instrument in Spanish to evaluate the performance of clinical teachers by students].
Bitran, Marcela; Mena, Beltrán; Riquelme, Arnoldo; Padilla, Oslando; Sánchez, Ignacio; Moreno, Rodrigo
2010-06-01
The modernization of clinical teaching has called for the creation of faculty development programs, and the design of suitable instruments to evaluate clinical teachers' performance. To report the development and validation of an instrument in Spanish designed to measure the students' perceptions of their clinical teachers' performance and to provide them with feedback to improve their teaching practices. In a process that included the active participation of authorities, professors in charge of courses and internships, clinical teachers, students and medical education experts, we developed a 30-item questionnaire called MEDUC30 to evaluate the performance of clinical teachers by their students. The internal validity was assessed by factor analysis of 5214 evaluations of 265 teachers, gathered from 2004 to 2007. The reliability was measured with the Cronbach's alpha coefficient and the generalizability coefficient (g). MEDUC30 had good content and construct validity. Its internal structure was compatible with four factors: patient-centered teaching, teaching skills, assessment skills and learning climate, and it proved to be consistent with the structure anticipated by the theory. The scores were highly reliable (Cronbach's alpha: 0.97); five evaluations per teacher were sufficient to reach a reliability coefficient (g) of 0.8. MEDUC30 is a valid, reliable and useful instrument to evaluate the performance of clinical teachers. To our knowledge, this is the first instrument in Spanish for which solid validity and reliability evidences have been reported. We hope that MEDUC30 will be used to improve medical education in Spanish-speaking medical schools, providing teachers a specific feedback upon which to improve their pedagogical practice, and authorities with valuable information for the assessment of their faculty.
Sensor Data Fusion with Z-Numbers and Its Application in Fault Diagnosis
Jiang, Wen; Xie, Chunhe; Zhuang, Miaoyan; Shou, Yehang; Tang, Yongchuan
2016-01-01
Sensor data fusion technology is widely employed in fault diagnosis. The information in a sensor data fusion system is characterized by not only fuzziness, but also partial reliability. Uncertain information of sensors, including randomness, fuzziness, etc., has been extensively studied recently. However, the reliability of a sensor is often overlooked or cannot be analyzed adequately. A Z-number, Z = (A, B), can represent the fuzziness and the reliability of information simultaneously, where the first component A represents a fuzzy restriction on the values of uncertain variables and the second component B is a measure of the reliability of A. In order to model and process the uncertainties in a sensor data fusion system reasonably, in this paper, a novel method combining the Z-number and Dempster–Shafer (D-S) evidence theory is proposed, where the Z-number is used to model the fuzziness and reliability of the sensor data and the D-S evidence theory is used to fuse the uncertain information of Z-numbers. The main advantages of the proposed method are that it provides a more robust measure of reliability to the sensor data, and the complementary information of multi-sensors reduces the uncertainty of the fault recognition, thus enhancing the reliability of fault detection. PMID:27649193
A semi-automated algorithm for hypothalamus volumetry in 3 Tesla magnetic resonance images.
Wolff, Julia; Schindler, Stephanie; Lucas, Christian; Binninger, Anne-Sophie; Weinrich, Luise; Schreiber, Jan; Hegerl, Ulrich; Möller, Harald E; Leitzke, Marco; Geyer, Stefan; Schönknecht, Peter
2018-07-30
The hypothalamus, a small diencephalic gray matter structure, is part of the limbic system. Volumetric changes of this structure occur in psychiatric diseases, therefore there is increasing interest in precise volumetry. Based on our detailed volumetry algorithm for 7 Tesla magnetic resonance imaging (MRI), we developed a method for 3 Tesla MRI, adopting anatomical landmarks and work in triplanar view. We overlaid T1-weighted MR images with gray matter-tissue probability maps to combine anatomical information with tissue class segmentation. Then, we outlined regions of interest (ROIs) that covered potential hypothalamus voxels. Within these ROIs, seed growing technique helped define the hypothalamic volume using gray matter probabilities from the tissue probability maps. This yielded a semi-automated method with short processing times of 20-40 min per hypothalamus. In the MRIs of ten subjects, reliabilities were determined as intraclass correlations (ICC) and volume overlaps in percent. Three raters achieved very good intra-rater reliabilities (ICC 0.82-0.97) and good inter-rater reliabilities (ICC 0.78 and 0.82). Overlaps of intra- and inter-rater runs were very good (≥ 89.7%). We present a fast, semi-automated method for in vivo hypothalamus volumetry in 3 Tesla MRI. Copyright © 2018 Elsevier B.V. All rights reserved.
Probabilistic Assessment of High-Throughput Wireless Sensor Networks
Kim, Robin E.; Mechitov, Kirill; Sim, Sung-Han; Spencer, Billie F.; Song, Junho
2016-01-01
Structural health monitoring (SHM) using wireless smart sensors (WSS) has the potential to provide rich information on the state of a structure. However, because of their distributed nature, maintaining highly robust and reliable networks can be challenging. Assessing WSS network communication quality before and after finalizing a deployment is critical to achieve a successful WSS network for SHM purposes. Early studies on WSS network reliability mostly used temporal signal indicators, composed of a smaller number of packets, to assess the network reliability. However, because the WSS networks for SHM purpose often require high data throughput, i.e., a larger number of packets are delivered within the communication, such an approach is not sufficient. Instead, in this study, a model that can assess, probabilistically, the long-term performance of the network is proposed. The proposed model is based on readily-available measured data sets that represent communication quality during high-throughput data transfer. Then, an empirical limit-state function is determined, which is further used to estimate the probability of network communication failure. Monte Carlo simulation is adopted in this paper and applied to a small and a full-bridge wireless networks. By performing the proposed analysis in complex sensor networks, an optimized sensor topology can be achieved. PMID:27258270
Dreiling, Katharina; Montano, Diego; Poinstingl, Herbert; Müller, Tjark; Schiekirka-Schwake, Sarah; Anders, Sven; von Steinbüchel, Nicole; Raupach, Tobias
2017-08-01
Evaluation is an integral part of curriculum development in medical education. Given the peculiarities of bedside teaching, specific evaluation tools for this instructional format are needed. Development of these tools should be informed by appropriate frameworks. The purpose of this study was to develop a specific evaluation tool for bedside teaching based on the Stanford Faculty Development Program's clinical teaching framework. Based on a literature review yielding 47 evaluation items, an 18-item questionnaire was compiled and subsequently completed by undergraduate medical students at two German universities. Reliability and validity were assessed in an exploratory full information item factor analysis (study one) and a confirmatory factor analysis as well as a measurement invariance analysis (study two). The exploratory analysis involving 824 students revealed a three-factor structure. Reliability estimates of the subscales were satisfactory (α = 0.71-0.84). The model yielded satisfactory fit indices in the confirmatory factor analysis involving 1043 students. The new questionnaire is short and yet based on a widely-used framework for clinical teaching. The analyses presented here indicate good reliability and validity of the instrument. Future research needs to investigate whether feedback generated from this tool helps to improve teaching quality and student learning outcome.
Understanding and Measuring Coach–Teacher Alliance: A Glimpse Inside the ‘Black Box’
Pas, Elise T.; Bradshaw, Catherine P.
2016-01-01
Coaching models are increasingly used in schools to enhance fidelity and effectiveness of evidence-based interventions; yet, little is known about the relationship between the coach and teacher (i.e., coach–teacher alliance), which may indirectly enhance teacher and student outcomes through improved implementation quality. There is also limited research on measures of coach–teacher alliance, further hindering the field from understanding the active components for successful coaching. The current study examined the factor structure and psychometric characteristics of a measure of coach–teacher alliance as reported by both teachers and coaches and explored the extent to which teachers and coaches reliably rate their alliance. Data come from a sample of 147 teachers who received implementation support from one of four coaches; both the teacher and the coach completed an alliance questionnaire. Separate confirmatory factor analyses for each informant revealed four factors (relationship, process, investment, and perceived benefits) as well as an additional coach-rated factor (perceived teacher barriers). A series of analyses, including cross-rater correlations, intraclass correlation coefficients, and Kuder-Richardson reliability estimates suggested that teachers and coaches provide reliable, though not redundant, information about the alliance. Implications for future research and the utilization of the parallel coach–teacher alliance measures to increase the effectiveness of coaching are discussed. PMID:26872479
Francis, Heather M; Osborne-Crowley, Katherine; McDonald, Skye
2017-01-01
To describe the reliability and validity of a new measure, the Social Skills Questionnaire for Traumatic Brain Injury (SSQ-TBI). Fifty-one adults with severe TBI completed the SSQ-TBI questionnaire. Scores were compared to informant- and self-report on questionnaires addressing frontal lobe mediated behaviour, as well as performance on an objective measure of social cognition and neuropsychological tasks, in order to provide evidence of concurrent, divergent and predictive validity. Internal consistency was excellent at α = 0.90. Convergent validity was good, with informant ratings on the SSQ-TBI significantly correlated with Neuropsychiatric Inventory Disinhibition sub-scales (r = 0.50-63), the Current Behaviour Scale (r = 0.39-0.48) and Frontal Systems Behaviour Scale (r = 0.60-0.83). However, no relationship was seen with an objective measure of social skills or neuropsychological tasks of disinhibition. There was a significant relationship with real-world psychosocial outcomes on the Sydney Psychosocial Reintegration Scale-2 (r = -0.38--0.69) Conclusions: This study provides preliminary findings of good internal consistency and convergent and predictive validity of a social skills questionnaire adapted to be appropriate for individuals with TBI. Further assessment of psychometric properties such as test-re-test reliability and factor structure is warranted.
The Hispanic Stress Inventory--Adolescent Version: a culturally informed psychosocial assessment.
Cervantes, Richard C; Fisher, Dennis G; Córdova, David; Napper, Lucy E
2012-03-01
A 2-phase study was conducted to develop a culturally informed measure of psychosocial stress for adolescents: the Hispanic Stress Inventory--Adolescent Version (HSI-A). Phase 1 involved item development through the collection of open-ended focus group interview data (n = 170) from a heterogeneous sample of Hispanic youths residing in the southwest and northeast United States. In Phase 2, we examined the psychometric properties of the HSI-A (n = 1,651), which involved the use of factor analytic procedures to determine the underlying scale structure of the HSI-A for foreign-born and U.S.-born participants in an aggregated analytic approach. An 8-factor solution was established, with factors that include Family Economic Stress, Acculturation-Gap Stress, Culture and Educational Stress, Immigration-Related Stress, Discrimination Stress, Family Immigration Stress, Community and Gang-Related Stress, and Family and Drug-Related Stress. Concurrent, related validity estimates were calculated to determine relations between HSI-A and other measures of child psychopathology and behavioral and emotional disturbances. HSI-A total stress appraisal scores were significantly correlated with both the Children's Depression Inventory and the Youth Self Report (p < .001). Reliability estimates for the HSI-A were conducted, and they yielded high reliability coefficients for most factor subscales, with the HSI-A total stress appraisal score reliability alpha at .92.
The Hispanic Stress Inventory-Adolescent Version: A Culturally Informed Psychosocial Assessment
Cervantes, Richard C.; Fisher, Dennis G.; Córdova, David; Napper, Lucy
2012-01-01
A 2-phase study was conducted to develop a culturally informed measure of psychosocial stress for adolescents, the Hispanic Stress Inventory-Adolescent Version (HSI-A). Phase I involved item development through the collection of open-ended focus group interview data (n=170) from a heterogeneous sample of Hispanic youth residing in the southwest and northeast United States. Phase 2 examined the psychometric properties of the HSI-A (n=1651) involving the use of factor analytic procedures to determine the underlying scale structure of the HSI-A, for foreign-born and U.S.-born participants in an aggregated analytic approach. An eight factor solution was established with factors that include Family Economic Stress, Acculturation Gaps Stress, Culture and Educational Stress, Immigration Related Stress, Discrimination Stress, Family Immigration Stress, Community and Gang Violence Stress and Family Drug Related Stress. Concurrent related validity estimates were calculated to determine relationships between HSI-A and other measures of child psychopathology, behavioral and emotional disturbances. HSI-A Total Stress Appraisal Scores were significantly correlated with both the CDI and YSR (p<.001 respectively). Reliability estimates for the HSI-A were conducted and yielded high reliability coefficients for most all factor sub-scales with HSI-A Total Stress Appraisal score reliability at alpha=.92. PMID:21942232
Behavioral pattern identification for structural health monitoring in complex systems
NASA Astrophysics Data System (ADS)
Gupta, Shalabh
Estimation of structural damage and quantification of structural integrity are critical for safe and reliable operation of human-engineered complex systems, such as electromechanical, thermofluid, and petrochemical systems. Damage due to fatigue crack is one of the most commonly encountered sources of structural degradation in mechanical systems. Early detection of fatigue damage is essential because the resulting structural degradation could potentially cause catastrophic failures, leading to loss of expensive equipment and human life. Therefore, for reliable operation and enhanced availability, it is necessary to develop capabilities for prognosis and estimation of impending failures, such as the onset of wide-spread fatigue crack damage in mechanical structures. This dissertation presents information-based online sensing of fatigue damage using the analytical tools of symbolic time series analysis ( STSA). Anomaly detection using STSA is a pattern recognition method that has been recently developed based upon a fixed-structure, fixed-order Markov chain. The analysis procedure is built upon the principles of Symbolic Dynamics, Information Theory and Statistical Pattern Recognition. The dissertation demonstrates real-time fatigue damage monitoring based on time series data of ultrasonic signals. Statistical pattern changes are measured using STSA to monitor the evolution of fatigue damage. Real-time anomaly detection is presented as a solution to the forward (analysis) problem and the inverse (synthesis) problem. (1) the forward problem - The primary objective of the forward problem is identification of the statistical changes in the time series data of ultrasonic signals due to gradual evolution of fatigue damage. (2) the inverse problem - The objective of the inverse problem is to infer the anomalies from the observed time series data in real time based on the statistical information generated during the forward problem. A computer-controlled special-purpose fatigue test apparatus, equipped with multiple sensing devices (e.g., ultrasonics and optical microscope) for damage analysis, has been used to experimentally validate the STSA method for early detection of anomalous behavior. The sensor information is integrated with a software module consisting of the STSA algorithm for real-time monitoring of fatigue damage. Experiments have been conducted under different loading conditions on specimens constructed from the ductile aluminium alloy 7075 - T6. The dissertation has also investigated the application of the STSA method for early detection of anomalies in other engineering disciplines. Two primary applications include combustion instability in a generic thermal pulse combustor model and whirling phenomenon in a typical misaligned shaft.
An experimental investigation of fault tolerant software structures in an avionics application
NASA Technical Reports Server (NTRS)
Caglayan, Alper K.; Eckhardt, Dave E., Jr.
1989-01-01
The objective of this experimental investigation is to compare the functional performance and software reliability of competing fault tolerant software structures utilizing software diversity. In this experiment, three versions of the redundancy management software for a skewed sensor array have been developed using three diverse failure detection and isolation algorithms and incorporated into various N-version, recovery block and hybrid software structures. The empirical results show that, for maximum functional performance improvement in the selected application domain, the results of diverse algorithms should be voted before being processed by multiple versions without enforced diversity. Results also suggest that when the reliability gain with an N-version structure is modest, recovery block structures are more feasible since higher reliability can be obtained using an acceptance check with a modest reliability.
Takegami, Yasuhiko; Seki, Taisuke; Amano, Takafumi; Higuchi, Yoshitoshi; Komatsu, Daigo; Nishida, Yoshihiro; Ishiguro, Naoki
2017-08-01
Although many patients use the internet to access health-related information, the quality and the reliability of the information is highly inconsistent. Periacetabular osteotomy (PAO) is one of the surgical procedures for hip dysplasia. However, medical information on PAO is limited on the internet. This study aims to evaluate the quality and reliability of information available on PAO on the internet in Japan. A web search was conducted on two search engines for the following terms: "hip osteotomy," "pelvic osteotomy," and "osteotomy for hip preservation" in Japanese. In total, we found 120 websites. To determine the quality and reliability of information on each website, we used the Health on the Net Foundation (HON) score, the Brief DISCERN score, and an osteotomy-specific content (OSC) score. After eliminating duplicate websites, we reviewed 49 unique websites. Only three websites (6.1%) had good reliability, as indicated by their HON scores. Twelve websites (24.4%) had good-quality information, as measured by their Brief DISCERN scores. As evaluated by their OSC scores, physician websites were found to be biased toward etiology and surgical indication and did not provide information on the complications of procedures. Non-physician websites were generally insufficient. The information about PAO on the internet is, therefore, unreliable and of poor-quality for Japanese patients.
Bahrami, Yadollah; Franco, Christopher M. M.
2015-01-01
Sea cucumbers produce numerous compounds with a wide range of chemical structural diversity. Among these, saponins are the most diverse and include sulfated, non-sulfated, acetylated and methylated congeners with different aglycone and sugar moieties. In this study, MALDI and ESI tandem mass spectrometry, in the positive ion mode, were used to elucidate the structure of new saponins extracted from the viscera of H. lessoni. Fragmentation of the aglycone provided structural information on the presence of the acetyl group. The presence of the O-acetyl group was confirmed by observing the mass transition of 60 u corresponding to the loss of a molecule of acetic acid. Ion fingerprints from the glycosidic cleavage provided information on the mass of the aglycone (core), and the sequence and type of monosaccharides that constitute the sugar moiety. The tandem mass spectra of the saponin precursor ions [M + Na]+ provided a wealth of detailed structural information on the glycosidic bond cleavages. As a result, and in conjunction with existing literature, we characterized the structure of five new acetylated saponins, Lessoniosides A–E, along with two non-acetylated saponins Lessoniosides F and G at m/z 1477.7, which are promising candidates for future drug development. The presented strategy allows a rapid, reliable and complete analysis of native saponins. PMID:25603350
Robust X-ray angular correlations for the study of meso-structures
Lhermitte, Julien R.; Tian, Cheng; Stein, Aaron; ...
2017-05-08
As self-assembling nanomaterials become more sophisticated, it is becoming increasingly important to measure the structural order of finite-sized assemblies of nano-objects. These mesoscale clusters represent an acute challenge to conventional structural probes, owing to the range of implicated size scales (10 nm to several micrometres), the weak scattering signal and the dynamic nature of meso-clusters in native solution environments. The high X-ray flux and coherence of modern synchrotrons present an opportunity to extract structural information from these challenging systems, but conventional ensemble X-ray scattering averages out crucial information about local particle configurations. Conversely, a single meso-cluster scatters too weakly tomore » recover the full diffraction pattern. Using X-ray angular cross-correlation analysis, it is possible to combine multiple noisy measurements to obtain robust structural information. This paper explores the key theoretical limits and experimental challenges that constrain the application of these methods to probing structural order in real nanomaterials. A metric is presented to quantify the signal-to-noise ratio of angular correlations, and it is used to identify several experimental artifacts that arise. In particular, it is found that background scattering, data masking and inter-cluster interference profoundly affect the quality of correlation analyses. A robust workflow is demonstrated for mitigating these effects and extracting reliable angular correlations from realistic experimental data.« less
77 FR 2963 - Commission Information Collection Activities (FERC-725F); Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-20
... submitting the information collection FERC-725F, ``Mandatory Reliability Standards for Nuclear Plant...: Title: FERC-725F Mandatory Reliability Standards for Nuclear Plant Interface Coordination OMB Control No... added a new section 215 to the FPA, which required a Commission-certified Electric Reliability...
Structural health monitoring in composite materials using frequency response methods
NASA Astrophysics Data System (ADS)
Kessler, Seth S.; Spearing, S. Mark; Atalla, Mauro J.; Cesnik, Carlos E. S.; Soutis, Constantinos
2001-08-01
Cost effective and reliable damage detection is critical for the utilization of composite materials in structural applications. Non-destructive evaluation techniques (e.g. ultrasound, radiography, infra-red imaging) are available for use during standard repair and maintenance cycles, however by comparison to the techniques used for metals these are relatively expensive and time consuming. This paper presents part of an experimental and analytical survey of candidate methods for the detection of damage in composite materials. The experimental results are presented for the application of modal analysis techniques applied to rectangular laminated graphite/epoxy specimens containing representative damage modes, including delamination, transverse ply cracks and through-holes. Changes in natural frequencies and modes were then found using a scanning laser vibrometer, and 2-D finite element models were created for comparison with the experimental results. The models accurately predicted the response of the specimems at low frequencies, but the local excitation and coalescence of higher frequency modes make mode-dependent damage detection difficult and most likely impractical for structural applications. The frequency response method was found to be reliable for detecting even small amounts of damage in a simple composite structure, however the potentially important information about damage type, size, location and orientation were lost using this method since several combinations of these variables can yield identical response signatures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Divan, Deepak; Brumsickle, William; Eto, Joseph
2003-04-01
This report describes a new approach for collecting information on power quality and reliability and making it available in the public domain. Making this information readily available in a form that is meaningful to electricity consumers is necessary for enabling more informed private and public decisions regarding electricity reliability. The system dramatically reduces the cost (and expertise) needed for customers to obtain information on the most significant power quality events, called voltage sags and interruptions. The system also offers widespread access to information on power quality collected from multiple sites and the potential for capturing information on the impacts ofmore » power quality problems, together enabling a wide variety of analysis and benchmarking to improve system reliability. Six case studies demonstrate selected functionality and capabilities of the system, including: Linking measured power quality events to process interruption and downtime; Demonstrating the ability to correlate events recorded by multiple monitors to narrow and confirm the causes of power quality events; and Benchmarking power quality and reliability on a firm and regional basis.« less
Reliability and validity of the Haitian Creole PHQ-9.
Marc, Linda G; Henderson, Whitney R; Desrosiers, Astrid; Testa, Marcia A; Jean, Samuel E; Akom, Eniko Edit
2014-12-01
There is limited information on depression in Haitians and this is partly attributable to the absence of culturally and linguistically adapted measures for depression. To perform a psychometric evaluation of the Haitian-Creole version of the PHQ-9 administered to men who have sex with men (MSM) in the Republic of Haiti. This study uses a cross-sectional design and data are from the Integrated Behavioral and Biological HIV Survey (IBBS) for MSM in Haiti. Inclusion criteria required that participants be male, ≥ 18 years, report sexual relations with a male partner in the last 12 months, and lived in Haiti during the past 3 months. Respondent Driven Sampling was used for participant recruitment. A structured questionnaire was verbally administered in Haitian-Creole capturing information on sociodemographics, sexual behaviors, human immunodeficiency virus (HIV) status and depressive symptomatology using the PHQ-9. Psychometric analyses of the translated PHQ-9 assessed unidimensionality, factor structure, reliability, construct validity, and differential item functioning (DIF) across subgroups (age, educational level, sexual orientation and HIV status). In a study population of 1,028 MSM, the Haitian-Creole version of the PHQ-9 is unidimensional, has moderately high internal consistency reliability (α = 0.78), and shows evidence of construct validity where HIV-positive subjects have greater depression (p = 0.002). There is no evidence of DIF across age, education, sexual orientation or HIV status. HIV-positive MSM are twice as likely to screen positive for moderately severe and severe depressive symptoms compared to their HIV-negative counterparts. There is strong evidence for the psychometric adequacy of the translated PHQ-9 screening tool as a measure of depression with MSM in Haiti. Future research is necessary to examine the predictive validity of depression for subsequent health behaviors or clinical outcomes among Haitian MSM.
Best Practices for Reliable and Robust Spacecraft Structures
NASA Technical Reports Server (NTRS)
Raju, Ivatury S.; Murthy, P. L. N.; Patel, Naresh R.; Bonacuse, Peter J.; Elliott, Kenny B.; Gordon, S. A.; Gyekenyesi, J. P.; Daso, E. O.; Aggarwal, P.; Tillman, R. F.
2007-01-01
A study was undertaken to capture the best practices for the development of reliable and robust spacecraft structures for NASA s next generation cargo and crewed launch vehicles. In this study, the NASA heritage programs such as Mercury, Gemini, Apollo, and the Space Shuttle program were examined. A series of lessons learned during the NASA and DoD heritage programs are captured. The processes that "make the right structural system" are examined along with the processes to "make the structural system right". The impact of technology advancements in materials and analysis and testing methods on reliability and robustness of spacecraft structures is studied. The best practices and lessons learned are extracted from these studies. Since the first human space flight, the best practices for reliable and robust spacecraft structures appear to be well established, understood, and articulated by each generation of designers and engineers. However, these best practices apparently have not always been followed. When the best practices are ignored or short cuts are taken, risks accumulate, and reliability suffers. Thus program managers need to be vigilant of circumstances and situations that tend to violate best practices. Adherence to the best practices may help develop spacecraft systems with high reliability and robustness against certain anomalies and unforeseen events.
1978-04-01
3 1.7 Production Rate Change Time . . . . 3 1.8 Time of Fatigue Test Start . ..... 3 1.9 Fatigue Test Acceleration Factor . 3 1.10 Corrosion...simulation logic. SAIFE accounts for the following factors : (1) aircraft design analysis; (2) component and full-scale fatigue testing; (3) production ...reliability; production , servi ce,Information Service, Springfield, and corrosion defects; crack or corrosi on Virginia 22151 detection probability; crack
Environmental Exposure and Design Criteria for Offshore Oil and Gas Structures
1980-05-01
reliability ar_alysis. Because there are no clear lines of demarcation between them, these methods are often used in varying combinations. Sound ...cludes that OCSEA-P not now effe.tively contribute...to the accrual of sound scientific information adequate for OCS management." One reason for such a...procedures for resolving differences need to be developed. Sound and timely assessments of environmental exposure risks will require: 1) adequate levels of
Kono, Yuko; Matsushima, Eisuke; Uji, Masayo
2014-02-01
The 25-item Work Limitations Questionnaire (WLQ-25) measures presenteeism but has not been sufficiently validated in a Japanese population. A total of 451 employees from four information technology companies in Tokyo completed the WLQ-25 and questionnaires of other variables on two occasions, 2 weeks apart. The WLQ-25 yielded a two-factor structure: Cognitive Demand and Physical Demand. These subscales showed good internal consistency, and both were associated with adverse working conditions, greater perceived job strain, lower skill use, poorer workplace social support, and less satisfactory psychological adjustment. Intraclass correlation coefficients of the two WLQ-25 subscales between time 1 and time 2 were 0.78 and 0.55, respectively. This study suggests acceptable psychometric properties of the WLQ-25 in Japan.
Study of structural reliability of existing concrete structures
NASA Astrophysics Data System (ADS)
Druķis, P.; Gaile, L.; Valtere, K.; Pakrastiņš, L.; Goremikins, V.
2017-10-01
Structural reliability of buildings has become an important issue after the collapse of a shopping center in Riga 21.11.2013, caused the death of 54 people. The reliability of a building is the practice of designing, constructing, operating, maintaining and removing buildings in ways that ensure maintained health, ward suffered injuries or death due to use of the building. Evaluation and improvement of existing buildings is becoming more and more important. For a large part of existing buildings, the design life has been reached or will be reached in the near future. The structures of these buildings need to be reassessed in order to find out whether the safety requirements are met. The safety requirements provided by the Eurocodes are a starting point for the assessment of safety. However, it would be uneconomical to require all existing buildings and structures to comply fully with these new codes and corresponding safety levels, therefore the assessment of existing buildings differs with each design situation. This case study describes the simple and practical procedure of determination of minimal reliability index β of existing concrete structures designed by different codes than Eurocodes and allows to reassess the actual reliability level of different structural elements of existing buildings under design load.
Tomography reconstruction methods for damage diagnosis of wood structure in construction field
NASA Astrophysics Data System (ADS)
Qiu, Qiwen; Lau, Denvid
2018-03-01
The structural integrity of wood building element plays a critical role in the public safety, which requires effective methods for diagnosis of internal damage inside the wood body. Conventionally, the non-destructive testing (NDT) methods such as X-ray computed tomography, thermography, radar imaging reconstruction method, ultrasonic tomography, nuclear magnetic imaging techniques, and sonic tomography have been used to obtain the information about the internal structure of wood. In this paper, the applications, advantages and disadvantages of these traditional tomography methods are reviewed. Additionally, the present article gives an overview of recently developed tomography approach that relies on the use of mechanical and electromagnetic waves for assessing the structural integrity of wood buildings. This developed tomography reconstruction method is believed to provide a more accurate, reliable, and comprehensive assessment of wood structural integrity
Hiratani, Naoki; Fukai, Tomoki
2016-01-01
In the adult mammalian cortex, a small fraction of spines are created and eliminated every day, and the resultant synaptic connection structure is highly nonrandom, even in local circuits. However, it remains unknown whether a particular synaptic connection structure is functionally advantageous in local circuits, and why creation and elimination of synaptic connections is necessary in addition to rich synaptic weight plasticity. To answer these questions, we studied an inference task model through theoretical and numerical analyses. We demonstrate that a robustly beneficial network structure naturally emerges by combining Hebbian-type synaptic weight plasticity and wiring plasticity. Especially in a sparsely connected network, wiring plasticity achieves reliable computation by enabling efficient information transmission. Furthermore, the proposed rule reproduces experimental observed correlation between spine dynamics and task performance. PMID:27303271
Reliability Modeling of Double Beam Bridge Crane
NASA Astrophysics Data System (ADS)
Han, Zhu; Tong, Yifei; Luan, Jiahui; Xiangdong, Li
2018-05-01
This paper briefly described the structure of double beam bridge crane and the basic parameters of double beam bridge crane are defined. According to the structure and system division of double beam bridge crane, the reliability architecture of double beam bridge crane system is proposed, and the reliability mathematical model is constructed.
Roelofs, Jeffrey; Muris, Peter; Braet, Caroline; Arntz, Arnoud; Beelen, Imke
2015-06-01
The Structured Clinical Interview for DSM-IV Childhood Disorders (Kid-SCID) is a semi-structured interview for the classification of psychiatric disorders in children and adolescents. This study presents a first evaluation of the psychometric properties of the Kid-SCID in a Dutch sample of children and adolescents who had been referred to an outpatient treatment centre for mental health problems. Results indicated that the inter-rater reliability of the Kid-SCID classifications and the internal consistency of various (dimensional) criteria of the diagnoses were moderate to good. Further, for most Kid-SCID diagnoses, reasonable agreement between children and parents was found. Finally, the correspondence between the Kid-SCID and the final clinical diagnosis as established after the full intake procedure, which included the information as provided by the Kid-SCID, ranged from poor to good. Results are discussed in the light of methodological issues pertaining to the assessment of psychiatric disorders in youths. The Kid-SCID can generally be seen as a reliable and useful tool that can assist clinicians in carrying out clinical evaluations of children and adolescents.
Namazi-Rad, Mohammad-Reza; Mokhtarian, Payam; Perez, Pascal
2014-01-01
Generating a reliable computer-simulated synthetic population is necessary for knowledge processing and decision-making analysis in agent-based systems in order to measure, interpret and describe each target area and the human activity patterns within it. In this paper, both synthetic reconstruction (SR) and combinatorial optimisation (CO) techniques are discussed for generating a reliable synthetic population for a certain geographic region (in Australia) using aggregated- and disaggregated-level information available for such an area. A CO algorithm using the quadratic function of population estimators is presented in this paper in order to generate a synthetic population while considering a two-fold nested structure for the individuals and households within the target areas. The baseline population in this study is generated from the confidentialised unit record files (CURFs) and 2006 Australian census tables. The dynamics of the created population is then projected over five years using a dynamic micro-simulation model for individual- and household-level demographic transitions. This projection is then compared with the 2011 Australian census. A prediction interval is provided for the population estimates obtained by the bootstrapping method, by which the variability structure of a predictor can be replicated in a bootstrap distribution. PMID:24733522
Efficient detection of contagious outbreaks in massive metropolitan encounter networks
Sun, Lijun; Axhausen, Kay W.; Lee, Der-Horng; Cebrian, Manuel
2014-01-01
Physical contact remains difficult to trace in large metropolitan networks, though it is a key vehicle for the transmission of contagious outbreaks. Co-presence encounters during daily transit use provide us with a city-scale time-resolved physical contact network, consisting of 1 billion contacts among 3 million transit users. Here, we study the advantage that knowledge of such co-presence structures may provide for early detection of contagious outbreaks. We first examine the “friend sensor” scheme - a simple, but universal strategy requiring only local information - and demonstrate that it provides significant early detection of simulated outbreaks. Taking advantage of the full network structure, we then identify advanced “global sensor sets”, obtaining substantial early warning times savings over the friends sensor scheme. Individuals with highest number of encounters are the most efficient sensors, with performance comparable to individuals with the highest travel frequency, exploratory behavior and structural centrality. An efficiency balance emerges when testing the dependency on sensor size and evaluating sensor reliability; we find that substantial and reliable lead-time could be attained by monitoring only 0.01% of the population with the highest degree. PMID:24903017
Partial volume correction of magnetic resonance spectroscopic imaging
NASA Astrophysics Data System (ADS)
Lu, Yao; Wu, Dee; Magnotta, Vincent A.
2007-03-01
The ability to study the biochemical composition of the brain is becoming important to better understand neurodegenerative and neurodevelopmental disorders. Magnetic Resonance Spectroscopy (MRS) can non-invasively provide quantification of brain metabolites in localized regions. The reliability of MRS is limited in part due to partial volume artifacts. This results from the relatively large voxels that are required to acquire sufficient signal-to-noise ratios for the studies. Partial volume artifacts result when a MRS voxel contains a mixture of tissue types. Concentrations of metabolites vary from tissue to tissue. When a voxel contains a heterogeneous tissue composition, the spectroscopic signal acquired from this voxel will consist of the signal from different tissues making reliable measurements difficult. We have developed a novel tool for the estimation of partial volume tissue composition within MRS voxels thus allowing for the correction of partial volume artifacts. In addition, the tool can localize MR spectra to anatomical regions of interest. The tool uses tissue classification information acquired as part of a structural MR scan for the same subject. The tissue classification information is co-registered with the spectroscopic data. The user can quantify the partial volume composition of each voxel and use this information as covariates for metabolite concentrations.
Intermediate- and short-range order in phosphorus-selenium glasses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bytchkov, Aleksei; Hennet, Louis; Price, David L.
2011-04-01
State-of-the-art neutron and x-ray diffraction measurements have been performed to provide a definitive picture of the intermediate- and short-range structures of P{sub x}Se{sub 1-x} glasses spanning two glass regions, x 0.025-0.54 and 0.64-0.84. Liquid P{sub 4}Se{sub 3} and amorphous red P and Se were also measured. Detailed information was obtained about the development with increasing phosphorous concentration of intermediate-range order on the length scale {approx}6 A ring , based on the behavior of the first sharp diffraction peak. Attention is also paid to the feature in the structure factor at 7.5 A ring {sup -1}, identified in earlier numerical simulations,more » provides further evidence of the existence of molecular units. The real-space transforms yield a reliable statistical picture of the changing short-range order as x increases, using the information about types and concentrations of local structural units provided by previous NMR measurements to interpret the trends observed.« less
A reliability analysis framework with Monte Carlo simulation for weld structure of crane's beam
NASA Astrophysics Data System (ADS)
Wang, Kefei; Xu, Hongwei; Qu, Fuzheng; Wang, Xin; Shi, Yanjun
2018-04-01
The reliability of the crane product in engineering is the core competitiveness of the product. This paper used Monte Carlo method analyzed the reliability of the weld metal structure of the bridge crane whose limit state function is mathematical expression. Then we obtained the minimum reliable welding feet height value for the welds between cover plate and web plate on main beam in different coefficients of variation. This paper provides a new idea and reference for the growth of the inherent reliability of crane.
Total systems design analysis of high performance structures
NASA Technical Reports Server (NTRS)
Verderaime, V.
1993-01-01
Designer-control parameters were identified at interdiscipline interfaces to optimize structural systems performance and downstream development and operations with reliability and least life-cycle cost. Interface tasks and iterations are tracked through a matrix of performance disciplines integration versus manufacturing, verification, and operations interactions for a total system design analysis. Performance integration tasks include shapes, sizes, environments, and materials. Integrity integrating tasks are reliability and recurring structural costs. Significant interface designer control parameters were noted as shapes, dimensions, probability range factors, and cost. Structural failure concept is presented, and first-order reliability and deterministic methods, benefits, and limitations are discussed. A deterministic reliability technique combining benefits of both is proposed for static structures which is also timely and economically verifiable. Though launch vehicle environments were primarily considered, the system design process is applicable to any surface system using its own unique filed environments.
Assessment of concrete damage and strength degradation caused by reinforcement corrosion
NASA Astrophysics Data System (ADS)
Nepal, Jaya; Chen, Hua-Peng
2015-07-01
Structural performance deterioration of reinforced concrete structures has been extensively investigated, but very limited studies have been carried out to investigate the effect of reinforcement corrosion on time-dependent reliability with consideration of the influence of mechanical characteristics of the bond interface due to corrosion. This paper deals with how corrosion in reinforcement creates different types of defects in concrete structure and how they are responsible for the structural capacity deterioration of corrosion affected reinforced concrete structures during their service life. Cracking in cover concrete due to reinforcement corrosion is investigated by using rebar-concrete model and realistic concrete properties. The flexural strength deterioration is analytically predicted on the basis of bond strength evolution due to reinforcement corrosion, which is examined by the experimental data available. The time-dependent reliability analysis is undertaken to calculate the life time structural reliability of corrosion damaged concrete structures by stochastic deterioration modelling of reinforced concrete. The results from the numerical example show that the proposed approach is capable of evaluating the damage caused by reinforcement corrosion and also predicting the structural reliability of concrete structures during their lifecycle.
Intersession reliability of fMRI activation for heat pain and motor tasks
Quiton, Raimi L.; Keaser, Michael L.; Zhuo, Jiachen; Gullapalli, Rao P.; Greenspan, Joel D.
2014-01-01
As the practice of conducting longitudinal fMRI studies to assess mechanisms of pain-reducing interventions becomes more common, there is a great need to assess the test–retest reliability of the pain-related BOLD fMRI signal across repeated sessions. This study quantitatively evaluated the reliability of heat pain-related BOLD fMRI brain responses in healthy volunteers across 3 sessions conducted on separate days using two measures: (1) intraclass correlation coefficients (ICC) calculated based on signal amplitude and (2) spatial overlap. The ICC analysis of pain-related BOLD fMRI responses showed fair-to-moderate intersession reliability in brain areas regarded as part of the cortical pain network. Areas with the highest intersession reliability based on the ICC analysis included the anterior midcingulate cortex, anterior insula, and second somatosensory cortex. Areas with the lowest intersession reliability based on the ICC analysis also showed low spatial reliability; these regions included pregenual anterior cingulate cortex, primary somatosensory cortex, and posterior insula. Thus, this study found regional differences in pain-related BOLD fMRI response reliability, which may provide useful information to guide longitudinal pain studies. A simple motor task (finger-thumb opposition) was performed by the same subjects in the same sessions as the painful heat stimuli were delivered. Intersession reliability of fMRI activation in cortical motor areas was comparable to previously published findings for both spatial overlap and ICC measures, providing support for the validity of the analytical approach used to assess intersession reliability of pain-related fMRI activation. A secondary finding of this study is that the use of standard ICC alone as a measure of reliability may not be sufficient, as the underlying variance structure of an fMRI dataset can result in inappropriately high ICC values; a method to eliminate these false positive results was used in this study and is recommended for future studies of test–retest reliability. PMID:25161897
NASA Astrophysics Data System (ADS)
Khatibinia, M.; Salajegheh, E.; Salajegheh, J.; Fadaee, M. J.
2013-10-01
A new discrete gravitational search algorithm (DGSA) and a metamodelling framework are introduced for reliability-based design optimization (RBDO) of reinforced concrete structures. The RBDO of structures with soil-structure interaction (SSI) effects is investigated in accordance with performance-based design. The proposed DGSA is based on the standard gravitational search algorithm (GSA) to optimize the structural cost under deterministic and probabilistic constraints. The Monte-Carlo simulation (MCS) method is considered as the most reliable method for estimating the probabilities of reliability. In order to reduce the computational time of MCS, the proposed metamodelling framework is employed to predict the responses of the SSI system in the RBDO procedure. The metamodel consists of a weighted least squares support vector machine (WLS-SVM) and a wavelet kernel function, which is called WWLS-SVM. Numerical results demonstrate the efficiency and computational advantages of DGSA and the proposed metamodel for RBDO of reinforced concrete structures.
Reconstruction of financial networks for robust estimation of systemic risk
NASA Astrophysics Data System (ADS)
Mastromatteo, Iacopo; Zarinelli, Elia; Marsili, Matteo
2012-03-01
In this paper we estimate the propagation of liquidity shocks through interbank markets when the information about the underlying credit network is incomplete. We show that techniques such as maximum entropy currently used to reconstruct credit networks severely underestimate the risk of contagion by assuming a trivial (fully connected) topology, a type of network structure which can be very different from the one empirically observed. We propose an efficient message-passing algorithm to explore the space of possible network structures and show that a correct estimation of the network degree of connectedness leads to more reliable estimations for systemic risk. Such an algorithm is also able to produce maximally fragile structures, providing a practical upper bound for the risk of contagion when the actual network structure is unknown. We test our algorithm on ensembles of synthetic data encoding some features of real financial networks (sparsity and heterogeneity), finding that more accurate estimations of risk can be achieved. Finally we find that this algorithm can be used to control the amount of information that regulators need to require from banks in order to sufficiently constrain the reconstruction of financial networks.
Li, Xiaonuo; Chen, Weiping; Cundy, Andrew B; Chang, Andrew C; Jiao, Wentao
2018-03-15
Public perception towards contaminated site management, a not readily quantifiable latent parameter, was linked through structural equation modeling in this paper to 22 measurable/observable manifest variables associated with the extent of information dissemination and public knowledge of soil pollution, attitude towards remediation policies, and participation in risk mitigation processes. Data obtained through a survey of 412 community residents at four remediation sites in China were employed in the model validation. The outcomes showed that public perception towards contaminated site management might be explained through selected measurable parameters in five categories, namely information disclosure, knowledge of soil pollution, expectations of remediation and redevelopment outcomes, public participation, and site policy, along with their interactions. Among these, information dissemination and attitude towards management policies exhibited significant influence in promoting positive public perception. Based on these examples, responsible agencies therefore should focus on public accessibility to reliable information, and encourage public inputs into policies for contaminated site management, in order to gain public confidence during remediation and regeneration projects. Copyright © 2018 Elsevier Ltd. All rights reserved.
Jackson, Howard F; Tunstall, Victoria; Hague, Gemma; Daniels, Leanne; Crompton, Stacey; Taplin, Kimberly
2014-01-01
Jackson et al. (this edition) argue that structure is an important component in reducing the handicaps caused by cognitive impairments following acquired brain injury and that post-acute neuropsychological brain injury rehabilitation programmes should not only endeavour to provide structure but also aim to develop self-structuring. However, at present there is no standardized device for assessing self-structuring. To provide preliminary analysis of the psychometric properties of the Behavioural Assessment of Self-Structuring (BASS) staff rating scale (a 26 item informant five point rating scale based on the degree of support client requires to achieve self-structuring item). BASS data was utilised for clients attending residential rehabilitation. Reliability (inter-rarer and intra-rater), validity (construct, concurrent and discriminate) and sensitivity to change were investigated. Initial results indicate that the BASS has reasonably good reliability, good construct validity (via principal components analysis), good discriminant validity, and good concurrent validity correlating well with a number of other outcome measures (HoNOS; NPDS, Supervision Rating Scale, MPAI, FIM and FAM). The BASS did not correlate well with the NPCNA. Finally, the BASS was shown to demonstrate sensitivity to change. Although some caution is required in drawing firm conclusions at the present time and further exploration of the psychometric properties of the BASS is required, initial results are encouraging for the use of the BASS in assessing rehabilitation progress. These findings are discussed in terms of the value of the concept of self-structuring to the rehabilitation process for individuals with neuropsychological impairments consequent on acquired brain injury.
NASA Astrophysics Data System (ADS)
Yu, Z. P.; Yue, Z. F.; Liu, W.
2018-05-01
With the development of artificial intelligence, more and more reliability experts have noticed the roles of subjective information in the reliability design of complex system. Therefore, based on the certain numbers of experiment data and expert judgments, we have divided the reliability estimation based on distribution hypothesis into cognition process and reliability calculation. Consequently, for an illustration of this modification, we have taken the information fusion based on intuitional fuzzy belief functions as the diagnosis model of cognition process, and finished the reliability estimation for the open function of cabin door affected by the imprecise judgment corresponding to distribution hypothesis.
What Are Your Patients Reading Online About Soft-tissue Fillers? An Analysis of Internet Information
Al Youha, Sarah A.; Bull, Courtney E.; Butler, Michael B.; Williams, Jason G.
2016-01-01
Background: Soft-tissue fillers are increasingly being used for noninvasive facial rejuvenation. They generally offer minimal downtime and reliable results. However, significant complications are reported and patients need to be aware of these as part of informed consent. The Internet serves as a vital resource to inform patients of the risks and benefits of this procedure. Methods: Three independent reviewers performed a structured analysis of 65 Websites providing information on soft-tissue fillers. Validated instruments were used to analyze each site across multiple domains, including readability, accessibility, reliability, usability, quality, and accuracy. Associations between the endpoints and Website characteristics were assessed using linear regression and proportional odds modeling. Results: The majority of Websites were physician private practice sites (36.9%) and authored by board-certified plastic surgeons or dermatologists (35.4%) or nonphysicians (27.7%). Sites had a mean Flesch-Kincaid grade level of 11.9 ± 2.6, which is well above the recommended average of 6 to 7 grade level. Physician private practice sites had the lowest scores across all domains with a notable lack of information on complications. Conversely, Websites of professional societies focused in plastic surgery and dermatology, as well as academic centers scored highest overall. Conclusions: As the use of soft-tissue fillers is rising, patients should be guided toward appropriate sources of information such as Websites sponsored by professional societies. Medical professionals should be aware that patients may be accessing poor information online and strive to improve the overall quality of information available on soft-tissue fillers. PMID:27536503
A Note on Structural Equation Modeling Estimates of Reliability
ERIC Educational Resources Information Center
Yang, Yanyun; Green, Samuel B.
2010-01-01
Reliability can be estimated using structural equation modeling (SEM). Two potential problems with this approach are that estimates may be unstable with small sample sizes and biased with misspecified models. A Monte Carlo study was conducted to investigate the quality of SEM estimates of reliability by themselves and relative to coefficient…
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…
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…
78 FR 58295 - Commission Information Collection Activities (FERC-725A); Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-23
... submitting the information collection FERC-725A, Mandatory Reliability Standards for the Bulk Power System... collection analysis associated with its approval of Reliability Standard EOP-004-2, in an order published in... solicitation and is making this notation in its submission to OMB. \\1\\ North American Electric Reliability Corp...
Optimal full motion video registration with rigorous error propagation
NASA Astrophysics Data System (ADS)
Dolloff, John; Hottel, Bryant; Doucette, Peter; Theiss, Henry; Jocher, Glenn
2014-06-01
Optimal full motion video (FMV) registration is a crucial need for the Geospatial community. It is required for subsequent and optimal geopositioning with simultaneous and reliable accuracy prediction. An overall approach being developed for such registration is presented that models relevant error sources in terms of the expected magnitude and correlation of sensor errors. The corresponding estimator is selected based on the level of accuracy of the a priori information of the sensor's trajectory and attitude (pointing) information, in order to best deal with non-linearity effects. Estimator choices include near real-time Kalman Filters and batch Weighted Least Squares. Registration solves for corrections to the sensor a priori information for each frame. It also computes and makes available a posteriori accuracy information, i.e., the expected magnitude and correlation of sensor registration errors. Both the registered sensor data and its a posteriori accuracy information are then made available to "down-stream" Multi-Image Geopositioning (MIG) processes. An object of interest is then measured on the registered frames and a multi-image optimal solution, including reliable predicted solution accuracy, is then performed for the object's 3D coordinates. This paper also describes a robust approach to registration when a priori information of sensor attitude is unavailable. It makes use of structure-from-motion principles, but does not use standard Computer Vision techniques, such as estimation of the Essential Matrix which can be very sensitive to noise. The approach used instead is a novel, robust, direct search-based technique.
The poor quality and reliability of information on periacetabular osteotomy on the internet in Japan
Takegami, Yasuhiko; Seki, Taisuke; Amano, Takafumi; Higuchi, Yoshitoshi; Komatsu, Daigo; Nishida, Yoshihiro; Ishiguro, Naoki
2017-01-01
ABSTRACT Although many patients use the internet to access health-related information, the quality and the reliability of the information is highly inconsistent. Periacetabular osteotomy (PAO) is one of the surgical procedures for hip dysplasia. However, medical information on PAO is limited on the internet. This study aims to evaluate the quality and reliability of information available on PAO on the internet in Japan. A web search was conducted on two search engines for the following terms: “hip osteotomy,” “pelvic osteotomy,” and “osteotomy for hip preservation” in Japanese. In total, we found 120 websites. To determine the quality and reliability of information on each website, we used the Health on the Net Foundation (HON) score, the Brief DISCERN score, and an osteotomy-specific content (OSC) score. After eliminating duplicate websites, we reviewed 49 unique websites. Only three websites (6.1%) had good reliability, as indicated by their HON scores. Twelve websites (24.4%) had good-quality information, as measured by their Brief DISCERN scores. As evaluated by their OSC scores, physician websites were found to be biased toward etiology and surgical indication and did not provide information on the complications of procedures. Non-physician websites were generally insufficient. The information about PAO on the internet is, therefore, unreliable and of poor-quality for Japanese patients. PMID:28878442
Critically re-evaluating a common technique: Accuracy, reliability, and confirmation bias of EMG.
Narayanaswami, Pushpa; Geisbush, Thomas; Jones, Lyell; Weiss, Michael; Mozaffar, Tahseen; Gronseth, Gary; Rutkove, Seward B
2016-01-19
(1) To assess the diagnostic accuracy of EMG in radiculopathy. (2) To evaluate the intrarater reliability and interrater reliability of EMG in radiculopathy. (3) To assess the presence of confirmation bias in EMG. Three experienced academic electromyographers interpreted 3 compact discs with 20 EMG videos (10 normal, 10 radiculopathy) in a blinded, standardized fashion without information regarding the nature of the study. The EMGs were interpreted 3 times (discs A, B, C) 1 month apart. Clinical information was provided only with disc C. Intrarater reliability was calculated by comparing interpretations in discs A and B, interrater reliability by comparing interpretation between reviewers. Confirmation bias was estimated by the difference in correct interpretations when clinical information was provided. Sensitivity was similar to previous reports (77%, confidence interval [CI] 63%-90%); specificity was 71%, CI 56%-85%. Intrarater reliability was good (κ 0.61, 95% CI 0.41-0.81); interrater reliability was lower (κ 0.53, CI 0.35-0.71). There was no substantial confirmation bias when clinical information was provided (absolute difference in correct responses 2.2%, CI -13.3% to 17.7%); the study lacked precision to exclude moderate confirmation bias. This study supports that (1) serial EMG studies should be performed by the same electromyographer since intrarater reliability is better than interrater reliability; (2) knowledge of clinical information does not bias EMG interpretation substantially; (3) EMG has moderate diagnostic accuracy for radiculopathy with modest specificity and electromyographers should exercise caution interpreting mild abnormalities. This study provides Class III evidence that EMG has moderate diagnostic accuracy and specificity for radiculopathy. © 2015 American Academy of Neurology.
Kobayashi, Hideyuki; Takemura, Yukie; Kanda, Katsuya
2011-09-01
Nursing is a labour-intensive field, and an extensive amount of latent information exists to aid in evaluating the quality of nursing service, with patients' experiences, the primary focus of such evaluations. To effect further improvement in nursing as well as medical care, Donabedian's structure-process-outcome approach has been applied. To classify and confirm patients' specific experiences with regard to nursing service based on Donabedian's structure-process-outcomes model for improving the quality of nursing care. Items were compiled from existing scales and assigned to structure, process or outcomes in Donabedian's model through discussion among expert nurses and pilot data collection. With regard to comfort, surroundings were classified as structure (e.g. accessibility to nurses, disturbance); with regard to patient-practitioner interaction, patient participation was classified as a process (e.g. expertise and skill, patient decision-making); and with regard to changes in patients, satisfaction was classified as an outcome (e.g. information support, overall satisfaction). Patient inquiry was carried out using the finalized questionnaire at general wards in Japanese hospitals in 2005-2006. Reliability and validity were tested using psychometric methods. Data from 1,810 patients (mean age: 59.7 years; mean length of stay: 23.7 days) were analysed. Internal consistency reliability was supported (α = 0.69-0.96), with factor analysis items of structure aggregated to one factor and overall satisfaction under outcome aggregated to one. The remaining items of outcome and process were distributed together in two factors. Inter-scale correlation (r = 0.442-0.807) supported the construct validity of each structure-process-outcome approach. All structure items were represented as negative-worded examples, as they dealt with basic conditions under Japanese universal health care system, and were regarded as representative related to concepts of dissatisfaction and no dissatisfaction. Patients' experiences with nursing service were confirmed using Donabedian's approach and can therefore be applied to improve quality of nursing practice by practitioners, managers and policy makers. © 2010 The Authors. Scandinavian Journal of Caring Sciences © 2010 Nordic College of Caring Science.
Structured Low-Density Parity-Check Codes with Bandwidth Efficient Modulation
NASA Technical Reports Server (NTRS)
Cheng, Michael K.; Divsalar, Dariush; Duy, Stephanie
2009-01-01
In this work, we study the performance of structured Low-Density Parity-Check (LDPC) Codes together with bandwidth efficient modulations. We consider protograph-based LDPC codes that facilitate high-speed hardware implementations and have minimum distances that grow linearly with block sizes. We cover various higher- order modulations such as 8-PSK, 16-APSK, and 16-QAM. During demodulation, a demapper transforms the received in-phase and quadrature samples into reliability information that feeds the binary LDPC decoder. We will compare various low-complexity demappers and provide simulation results for assorted coded-modulation combinations on the additive white Gaussian noise and independent Rayleigh fading channels.
Social Information Is Integrated into Value and Confidence Judgments According to Its Reliability.
De Martino, Benedetto; Bobadilla-Suarez, Sebastian; Nouguchi, Takao; Sharot, Tali; Love, Bradley C
2017-06-21
How much we like something, whether it be a bottle of wine or a new film, is affected by the opinions of others. However, the social information that we receive can be contradictory and vary in its reliability. Here, we tested whether the brain incorporates these statistics when judging value and confidence. Participants provided value judgments about consumer goods in the presence of online reviews. We found that participants updated their initial value and confidence judgments in a Bayesian fashion, taking into account both the uncertainty of their initial beliefs and the reliability of the social information. Activity in dorsomedial prefrontal cortex tracked the degree of belief update. Analogous to how lower-level perceptual information is integrated, we found that the human brain integrates social information according to its reliability when judging value and confidence. SIGNIFICANCE STATEMENT The field of perceptual decision making has shown that the sensory system integrates different sources of information according to their respective reliability, as predicted by a Bayesian inference scheme. In this work, we hypothesized that a similar coding scheme is implemented by the human brain to process social signals and guide complex, value-based decisions. We provide experimental evidence that the human prefrontal cortex's activity is consistent with a Bayesian computation that integrates social information that differs in reliability and that this integration affects the neural representation of value and confidence. Copyright © 2017 De Martino et al.
Bastien, Olivier; Maréchal, Eric
2008-08-07
Confidence in pairwise alignments of biological sequences, obtained by various methods such as Blast or Smith-Waterman, is critical for automatic analyses of genomic data. Two statistical models have been proposed. In the asymptotic limit of long sequences, the Karlin-Altschul model is based on the computation of a P-value, assuming that the number of high scoring matching regions above a threshold is Poisson distributed. Alternatively, the Lipman-Pearson model is based on the computation of a Z-value from a random score distribution obtained by a Monte-Carlo simulation. Z-values allow the deduction of an upper bound of the P-value (1/Z-value2) following the TULIP theorem. Simulations of Z-value distribution is known to fit with a Gumbel law. This remarkable property was not demonstrated and had no obvious biological support. We built a model of evolution of sequences based on aging, as meant in Reliability Theory, using the fact that the amount of information shared between an initial sequence and the sequences in its lineage (i.e., mutual information in Information Theory) is a decreasing function of time. This quantity is simply measured by a sequence alignment score. In systems aging, the failure rate is related to the systems longevity. The system can be a machine with structured components, or a living entity or population. "Reliability" refers to the ability to operate properly according to a standard. Here, the "reliability" of a sequence refers to the ability to conserve a sufficient functional level at the folded and maturated protein level (positive selection pressure). Homologous sequences were considered as systems 1) having a high redundancy of information reflected by the magnitude of their alignment scores, 2) which components are the amino acids that can independently be damaged by random DNA mutations. From these assumptions, we deduced that information shared at each amino acid position evolved with a constant rate, corresponding to the information hazard rate, and that pairwise sequence alignment scores should follow a Gumbel distribution, which parameters could find some theoretical rationale. In particular, one parameter corresponds to the information hazard rate. Extreme value distribution of alignment scores, assessed from high scoring segments pairs following the Karlin-Altschul model, can also be deduced from the Reliability Theory applied to molecular sequences. It reflects the redundancy of information between homologous sequences, under functional conservative pressure. This model also provides a link between concepts of biological sequence analysis and of systems biology.
Protein-Protein Interface Predictions by Data-Driven Methods: A Review
Xue, Li C; Dobbs, Drena; Bonvin, Alexandre M.J.J.; Honavar, Vasant
2015-01-01
Reliably pinpointing which specific amino acid residues form the interface(s) between a protein and its binding partner(s) is critical for understanding the structural and physicochemical determinants of protein recognition and binding affinity, and has wide applications in modeling and validating protein interactions predicted by high-throughput methods, in engineering proteins, and in prioritizing drug targets. Here, we review the basic concepts, principles and recent advances in computational approaches to the analysis and prediction of protein-protein interfaces. We point out caveats for objectively evaluating interface predictors, and discuss various applications of data-driven interface predictors for improving energy model-driven protein-protein docking. Finally, we stress the importance of exploiting binding partner information in reliably predicting interfaces and highlight recent advances in this emerging direction. PMID:26460190
NASA Astrophysics Data System (ADS)
Abdenov, A. Zh; Trushin, V. A.; Abdenova, G. A.
2018-01-01
The paper considers the questions of filling the relevant SIEM nodes based on calculations of objective assessments in order to improve the reliability of subjective expert assessments. The proposed methodology is necessary for the most accurate security risk assessment of information systems. This technique is also intended for the purpose of establishing real-time operational information protection in the enterprise information systems. Risk calculations are based on objective estimates of the adverse events implementation probabilities, predictions of the damage magnitude from information security violations. Calculations of objective assessments are necessary to increase the reliability of the proposed expert assessments.
Recent developments of the NESSUS probabilistic structural analysis computer program
NASA Technical Reports Server (NTRS)
Millwater, H.; Wu, Y.-T.; Torng, T.; Thacker, B.; Riha, D.; Leung, C. P.
1992-01-01
The NESSUS probabilistic structural analysis computer program combines state-of-the-art probabilistic algorithms with general purpose structural analysis methods to compute the probabilistic response and the reliability of engineering structures. Uncertainty in loading, material properties, geometry, boundary conditions and initial conditions can be simulated. The structural analysis methods include nonlinear finite element and boundary element methods. Several probabilistic algorithms are available such as the advanced mean value method and the adaptive importance sampling method. The scope of the code has recently been expanded to include probabilistic life and fatigue prediction of structures in terms of component and system reliability and risk analysis of structures considering cost of failure. The code is currently being extended to structural reliability considering progressive crack propagation. Several examples are presented to demonstrate the new capabilities.
Expected Utility Based Decision Making under Z-Information and Its Application.
Aliev, Rashad R; Mraiziq, Derar Atallah Talal; Huseynov, Oleg H
2015-01-01
Real-world decision relevant information is often partially reliable. The reasons are partial reliability of the source of information, misperceptions, psychological biases, incompetence, and so forth. Z-numbers based formalization of information (Z-information) represents a natural language (NL) based value of a variable of interest in line with the related NL based reliability. What is important is that Z-information not only is the most general representation of real-world imperfect information but also has the highest descriptive power from human perception point of view as compared to fuzzy number. In this study, we present an approach to decision making under Z-information based on direct computation over Z-numbers. This approach utilizes expected utility paradigm and is applied to a benchmark decision problem in the field of economics.
The Evolving Contribution of Mass Spectrometry to Integrative Structural Biology
NASA Astrophysics Data System (ADS)
Faini, Marco; Stengel, Florian; Aebersold, Ruedi
2016-06-01
Protein complexes are key catalysts and regulators for the majority of cellular processes. Unveiling their assembly and structure is essential to understanding their function and mechanism of action. Although conventional structural techniques such as X-ray crystallography and NMR have solved the structure of important protein complexes, they cannot consistently deal with dynamic and heterogeneous assemblies, limiting their applications to small scale experiments. A novel methodological paradigm, integrative structural biology, aims at overcoming such limitations by combining complementary data sources into a comprehensive structural model. Recent applications have shown that a range of mass spectrometry (MS) techniques are able to generate interaction and spatial restraints (cross-linking MS) information on native complexes or to study the stoichiometry and connectivity of entire assemblies (native MS) rapidly, reliably, and from small amounts of substrate. Although these techniques by themselves do not solve structures, they do provide invaluable structural information and are thus ideally suited to contribute to integrative modeling efforts. The group of Brian Chait has made seminal contributions in the use of mass spectrometric techniques to study protein complexes. In this perspective, we honor the contributions of the Chait group and discuss concepts and milestones of integrative structural biology. We also review recent examples of integration of structural MS techniques with an emphasis on cross-linking MS. We then speculate on future MS applications that would unravel the dynamic nature of protein complexes upon diverse cellular states.
Lai, Claudia K Y
2014-01-01
The Neuropsychiatric Inventory (NPI) is one of the most commonly used assessment scales for assessing symptoms in people with dementia and other neurological disorders. This paper analyzes its conceptual framework, measurement mode, psychometric properties, and merits and problems. All articles discussing the psychometric properties and factor structure of the NPI were searched for in Medline via Ovid. The abstracts of these papers were read to determine their relevance to the purpose of this paper. If deemed appropriate, a full paper was then obtained and read. The NPI has reasonably good content validity and internal consistency, and good test-retest and interrater reliability. There is limited information about its sensitivity, specificity, positive and negative predictive values, and, in particular, responsiveness. Merits of the NPI include being comprehensive, avoiding symptom overlap, ease of use, and flexibility. It has problems in scoring (no multiples of 5, 7, and 11) and, therefore, analysis using parametric tests may not be appropriate. The use of individual subscales also warrants further investigation. In terms of its content and concurrent validity, intra- and interrater reliability, test-retest reliability, and internal consistency, the NPI can be considered as valid and reliable, and can be used across different ethnic groups. The tool is most likely unable to deliver as good a performance in terms of discriminating between different disorders. More studies are required to further evaluate its psychometric properties, particularly in the areas of factor structure and responsiveness. The clinical utility of the NPI also needs to be further explored.
Reid, Matthew W; Hannemann, Nathan P; York, Gerald E; Ritter, John L; Kini, Jonathan A; Lewis, Jeffrey D; Sherman, Paul M; Velez, Carmen S; Drennon, Ann Marie; Bolzenius, Jacob D; Tate, David F
2017-07-01
To compare volumetric results from NeuroQuant® and FreeSurfer in a service member setting. Since the advent of medical imaging, quantification of brain anatomy has been a major research and clinical effort. Rapid advancement of methods to automate quantification and to deploy this information into clinical practice has surfaced in recent years. NeuroQuant® is one such tool that has recently been used in clinical settings. Accurate volumetric data are useful in many clinical indications; therefore, it is important to assess the intermethod reliability and concurrent validity of similar volume quantifying tools. Volumetric data from 148 U.S. service members across three different experimental groups participating in a study of mild traumatic brain injury (mTBI) were examined. Groups included mTBI (n = 71), posttraumatic stress disorder (n = 22), or a noncranial orthopedic injury (n = 55). Correlation coefficients and nonparametric group mean comparisons were used to assess reliability and concurrent validity, respectively. Comparison of these methods across our entire sample demonstrates generally fair to excellent reliability as evidenced by large intraclass correlation coefficients (ICC = .4 to .99), but little concurrent validity as evidenced by significantly different Mann-Whitney U comparisons for 26 of 30 brain structures measured. While reliability between the two segmenting tools is fair to excellent, volumetric outcomes are statistically different between the two methods. As suggested by both developers, structure segmentation should be visually verified prior to clinical use and rigor should be used when interpreting results generated by either method. Copyright © 2017 by the American Society of Neuroimaging.
Measures of the food environment: a compilation of the literature, 1990-2007.
McKinnon, Robin A; Reedy, Jill; Morrissette, Meredith A; Lytle, Leslie A; Yaroch, Amy L
2009-04-01
Valid and reliable measures are required to assess any effect of the food environment on individual dietary behavior, and form the foundation of research that may inform obesity-related policy. Although many methods of measuring the food environment exist, this area of research is still relatively new and there has been no systematic attempt to gather these measures, to compare and contrast them, or to report on their psychometric properties. A structured literature search was conducted to identify peer-reviewed articles published between January 1990 and August 2007 that measured the community-level food environment. These articles were categorized into the following environments: food stores, restaurants, schools, and worksites. The measurement strategies in these studies were categorized as instruments (checklists, market baskets, inventories, or interviews/questionnaires) or methodologies (geographic, sales, menu, or nutrient analyses). A total of 137 articles were identified that included measures of the food environment. Researchers focused on assessing the accessibility, availability, affordability, and quality of the food environment. The most frequently used measure overall was some form of geographic analysis. Eighteen of the 137 articles (13.1%) tested for any psychometric properties, including inter-rater reliability, test-retest reliability, and/or validity. A greater focus on testing for reliability and validity of measures of the food environment may increase rigor in research in this area. Robust measures of the food environment may strengthen research on the effects of the community-level food environment on individual dietary behavior, assist in the development and evaluation of interventions, and inform policymaking targeted at reducing the prevalence of obesity and improving diet.
Wireless sensor placement for structural monitoring using information-fusing firefly algorithm
NASA Astrophysics Data System (ADS)
Zhou, Guang-Dong; Yi, Ting-Hua; Xie, Mei-Xi; Li, Hong-Nan
2017-10-01
Wireless sensor networks (WSNs) are promising technology in structural health monitoring (SHM) applications for their low cost and high efficiency. The limited wireless sensors and restricted power resources in WSNs highlight the significance of optimal wireless sensor placement (OWSP) during designing SHM systems to enable the most useful information to be captured and to achieve the longest network lifetime. This paper presents a holistic approach, including an optimization criterion and a solution algorithm, for optimally deploying self-organizing multi-hop WSNs on large-scale structures. The combination of information effectiveness represented by the modal independence and the network performance specified by the network connectivity and network lifetime is first formulated to evaluate the performance of wireless sensor configurations. Then, an information-fusing firefly algorithm (IFFA) is developed to solve the OWSP problem. The step sizes drawn from a Lévy distribution are adopted to drive fireflies toward brighter individuals. Following the movement with Lévy flights, information about the contributions of wireless sensors to the objective function as carried by the fireflies is fused and applied to move inferior wireless sensors to better locations. The reliability of the proposed approach is verified via a numerical example on a long-span suspension bridge. The results demonstrate that the evaluation criterion provides a good performance metric of wireless sensor configurations, and the IFFA outperforms the simple discrete firefly algorithm.
Geierhaas, Christian D; Salvatella, Xavier; Clarke, Jane; Vendruscolo, Michele
2008-03-01
It has been suggested that Phi-values, which allow structural information about transition states (TSs) for protein folding to be obtained, are most reliably interpreted when divided into three classes (high, medium and low). High Phi-values indicate almost completely folded regions in the TS, intermediate Phi-values regions with a detectable amount of structure and low Phi-values indicate mostly unstructured regions. To explore the extent to which this classification can be used to characterise in detail the structure of TSs for protein folding, we used Phi-values divided into these classes as restraints in molecular dynamics simulations. This type of procedure is related to that used in NMR spectroscopy to define the structure of native proteins from the measurement of inter-proton distances derived from nuclear Overhauser effects. We illustrate this approach by determining the TS ensembles of five proteins and by showing that the results are similar to those obtained by using as restraints the actual numerical Phi-values measured experimentally. Our results indicate that the simultaneous consideration of a set of low-resolution Phi-values can provide sufficient information for characterising the architecture of a TS for folding of a protein.
Geierhaas, Christian D.; Salvatella, Xavier; Clarke, Jane; Vendruscolo, Michele
2008-01-01
It has been suggested that Φ-values, which allow structural information about transition states (TSs) for protein folding to be obtained, are most reliably interpreted when divided into three classes (high, medium and low). High Φ-values indicate almost completely folded regions in the TS, intermediate Φ-values regions with a detectable amount of structure and low Φ-values indicate mostly unstructured regions. To explore the extent to which this classification can be used to characterise in detail the structure of TSs for protein folding, we used Φ-values divided into these classes as restraints in molecular dynamics simulations. This type of procedure is related to that used in NMR spectroscopy to define the structure of native proteins from the measurement of inter-proton distances derived from nuclear Overhauser effects. We illustrate this approach by determining the TS ensembles of five proteins and by showing that the results are similar to those obtained by using as restraints the actual numerical Φ-values measured experimentally. Our results indicate that the simultaneous consideration of a set of low-resolution Φ-values can provide sufficient information for characterising the architecture of a TS for folding of a protein. PMID:18299294
Fatigue reliability of deck structures subjected to correlated crack growth
NASA Astrophysics Data System (ADS)
Feng, G. Q.; Garbatov, Y.; Guedes Soares, C.
2013-12-01
The objective of this work is to analyse fatigue reliability of deck structures subjected to correlated crack growth. The stress intensity factors of the correlated cracks are obtained by finite element analysis and based on which the geometry correction functions are derived. The Monte Carlo simulations are applied to predict the statistical descriptors of correlated cracks based on the Paris-Erdogan equation. A probabilistic model of crack growth as a function of time is used to analyse the fatigue reliability of deck structures accounting for the crack propagation correlation. A deck structure is modelled as a series system of stiffened panels, where a stiffened panel is regarded as a parallel system composed of plates and are longitudinal. It has been proven that the method developed here can be conveniently applied to perform the fatigue reliability assessment of structures subjected to correlated crack growth.
Tolu, Sena; Yurdakul, Ozan Volkan; Basaran, Betul; Rezvani, Aylin
2018-05-14
The aim of this study was to evaluate the reliability, content, and quality of videos for patients available on YouTube for learning how to self-administer subcutaneous anti-tumour necrosis factor (TNF) injections. We searched for the terms Humira injection, Enbrel injection, Simponi injection, and Cimzia injection. Videos were categorised as useful information, misleading information, useful patient opinion, and misleading patient opinion by two physicians. Videos were rated for quality on a 5-point global quality scale (GQS; 1 = poor quality, 5 = excellent quality) and reliability and content using the 5-point DISCERN scale (higher scores represent greater reliability and more comprehensive videos). Of the 142 English videos, 24 (16.9%) videos were classified as useful information, 6 (4.2%) as misleading information, 47 (33.1%) as useful patient opinion, and 65 (45.8%) as misleading patient opinion. Useful videos were the most comprehensive and had the highest reliability and quality scores. The useful information and useful patient opinion videos had the highest numbers of views per day (median 8.32, IQR: 3.40-14.28 and 5.46, IQR: 3.06-14.44), as compared with 2.32, IQR: 1.63-6.26 for misleading information videos and 2.15, IQR: 1.17-7.43 for misleading patient opinion videos (p = 0.001). Almost all (91.5%) misleading videos were uploaded by individual users. There are a substantial number of English-language YouTube videos, with high quality, and rich content and reliability that can be sources of information on proper technique of anti-TNF self-injections. Physicians should direct patients to the reliable resources of information and educate them in online resource assessment, thereby improving treatment outcomes.
ERIC Educational Resources Information Center
Green, Samuel B.; Yang, Yanyun
2009-01-01
A method is presented for estimating reliability using structural equation modeling (SEM) that allows for nonlinearity between factors and item scores. Assuming the focus is on consistency of summed item scores, this method for estimating reliability is preferred to those based on linear SEM models and to the most commonly reported estimate of…
Interval Estimation of Revision Effect on Scale Reliability via Covariance Structure Modeling
ERIC Educational Resources Information Center
Raykov, Tenko
2009-01-01
A didactic discussion of a procedure for interval estimation of change in scale reliability due to revision is provided, which is developed within the framework of covariance structure modeling. The method yields ranges of plausible values for the population gain or loss in reliability of unidimensional composites, which results from deletion or…
Terluin, Berend; Smits, Niels; Brouwers, Evelien P M; de Vet, Henrica C W
2016-09-15
The Four-Dimensional Symptom Questionnaire (4DSQ) is a self-report questionnaire measuring distress, depression, anxiety and somatization with separate scales. The 4DSQ has extensively been validated in clinical samples, especially from primary care settings. Information about measurement properties and normative data in the general population was lacking. In a Dutch general population sample we examined the 4DSQ scales' structure, the scales' reliability and measurement invariance with respect to gender, age and education, the scales' score distributions across demographic categories, and normative data. 4DSQ data were collected in a representative Dutch Internet panel. Confirmatory factor analysis was used to examine the scales' structure. Reliability was examined by Cronbach's alpha, and coefficients omega-total and omega-hierarchical. Differential item functioning (DIF) analysis was used to evaluate measurement invariance across gender, age and education. The total response rate was 82.4 % (n = 5273/6399). The depression scale proved to be unidimensional. The other scales were best represented as bifactor models consisting of a large general factor and one or more smaller specific factors. The general factors accounted for more than 95 % of the reliable variance of the scales. Reliability was high (≥0.85) by all estimates. The distress-, depression- and anxiety scales were invariant across gender, age and education. The somatization scale demonstrated some lack of measurement invariance as a result of decreased thresholds for some of the items in young people (16-24 years) and increased thresholds in elderly people (65+ years). The somatization scale was invariant regarding gender and education. The 4DSQ scores varied significantly across demographic categories, but the explained variance was small (<6 %). Normative data were generated for gender and age categories. Approximately 17 % of the participants scored above average on de distress scale, whereas 12 % scored above average on de somatization scale. Percentages of people scoring high enough on depression or anxiety as to suspect the presence of depressive or anxiety disorder were 4.1 and 2.5 respectively. Evidence supports reliability and measurement invariance of the 4DSQ in the general Dutch population. The normative data provided in this study can be used to compare a subject's 4DSQ scores with a general population reference group.
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.
Soldier Dimensions in Combat Models
1990-05-07
and performance. Questionnaires, SQTs, and ARTEPs were often used. Many scales had estimates of reliability but few had validity data. Most studies...pending its validation . Research plans were provided for applications in simulated combat and with simulation devices, for data previously gathered...regarding reliability and validity . Lack of information following an instrument indicates neither reliability nor validity information was provided by the
Probabilistic sizing of laminates with uncertainties
NASA Technical Reports Server (NTRS)
Shah, A. R.; Liaw, D. G.; Chamis, C. C.
1993-01-01
A reliability based design methodology for laminate sizing and configuration for a special case of composite structures is described. The methodology combines probabilistic composite mechanics with probabilistic structural analysis. The uncertainties of constituent materials (fiber and matrix) to predict macroscopic behavior are simulated using probabilistic theory. Uncertainties in the degradation of composite material properties are included in this design methodology. A multi-factor interaction equation is used to evaluate load and environment dependent degradation of the composite material properties at the micromechanics level. The methodology is integrated into a computer code IPACS (Integrated Probabilistic Assessment of Composite Structures). Versatility of this design approach is demonstrated by performing a multi-level probabilistic analysis to size the laminates for design structural reliability of random type structures. The results show that laminate configurations can be selected to improve the structural reliability from three failures in 1000, to no failures in one million. Results also show that the laminates with the highest reliability are the least sensitive to the loading conditions.
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.
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.
NASA Astrophysics Data System (ADS)
Tang, Qingjie; Guo, Zhenfu; Li, Qingzhong
2014-03-01
The complexes of cyanoacetaldehyde and hypohalous acid (HOX, X = Cl, Br, and I) have been investigated. They can form six different structures (A, B, C, D, E, and F), the former three structures are mainly combined through a N(O)⋯X halogen bond and the latter three structures are maintained mainly by a N(O)⋯H hydrogen bond, although other weaker interactions are also present in most structures. The hydrogen-bonded structures are more stable than the respective halogen-bonded structures. The Osbnd H and Osbnd X bonds in the halogen- and hydrogen-bonded complexes are lengthened and show an observed red shift, while those in the weaker secondary interactions are contracted and display a small blue shift. The orbital interactions in NBO analysis and the electron densities in AIM analysis provide useful and reliable information for the strength of each type of interaction in different structures.
Dima, Alexandra Lelia; Schulz, Peter Johannes
2017-01-01
Background The eHealth Literacy Scale (eHEALS) is a tool to assess consumers’ comfort and skills in using information technologies for health. Although evidence exists of reliability and construct validity of the scale, less agreement exists on structural validity. Objective The aim of this study was to validate the Italian version of the eHealth Literacy Scale (I-eHEALS) in a community sample with a focus on its structural validity, by applying psychometric techniques that account for item difficulty. Methods Two Web-based surveys were conducted among a total of 296 people living in the Italian-speaking region of Switzerland (Ticino). After examining the latent variables underlying the observed variables of the Italian scale via principal component analysis (PCA), fit indices for two alternative models were calculated using confirmatory factor analysis (CFA). The scale structure was examined via parametric and nonparametric item response theory (IRT) analyses accounting for differences between items regarding the proportion of answers indicating high ability. Convergent validity was assessed by correlations with theoretically related constructs. Results CFA showed a suboptimal model fit for both models. IRT analyses confirmed all items measure a single dimension as intended. Reliability and construct validity of the final scale were also confirmed. The contrasting results of factor analysis (FA) and IRT analyses highlight the importance of considering differences in item difficulty when examining health literacy scales. Conclusions The findings support the reliability and validity of the translated scale and its use for assessing Italian-speaking consumers’ eHealth literacy. PMID:28400356
Measuring Maladaptive Cognitions in Complicated Grief: Introducing the Typical Beliefs Questionnaire
Skritskaya, Natalia A.; Mauro, Christine; Olonoff, Matthew; Qiu, Xin; Duncan, Sarah; Wang, Yuanjia; Duan, Naihua; Lebowitz, Barry; Reynolds, Charles F.; Simon, Naomi M.; Zisook, Sidney; Shear, M. Katherine
2016-01-01
Objectives Maladaptive cognitions related to loss are thought to contribute to development of complicated grief and are crucial to address in treatment, but tools available to assess them are limited. This paper introduces the Typical Beliefs Questionnaire (TBQ), a 25-item self-report instrument to assess cognitions that interfere with adaptation to loss. Design Study participants completed an assessment battery during their initial evaluation and again after completing treatment at 20 weeks. Test-retest reliability was assessed on a subsample of the participants who did not show change in complicated grief severity after the first four weeks of treatment. To examine latent structure of the TBQ, an exploratory factor analysis (EFA) was performed. Setting Academic medical centers in Boston, New York, Pittsburgh and San Diego from 2010–2014. Participants 394 bereaved adults who met criteria for complicated grief. Measurements The TBQ along with assessments of complicated grief symptoms and related avoidance, depression symptoms, functional impairment, and perceived social support. Results The TBQ exhibited good internal consistency (α= .82) and test-retest reliability (n=105; ICC= .74). EFA indicated a five-factor structure: “Protesting the Death,” “Negative Thoughts About the World,” “Needing the Person,” “Less Grief is Wrong” and “Grieving Too Much.” The total score and all factors showed sensitivity to change with treatment. Conclusions This new tool allows a clinician to quickly and reliably ascertain presence of specific maladaptive cognitions related to complicated grief, and subsequently, to use the information to aid a diagnostic assessment, to structure the treatment, and to measure treatment outcomes. PMID:27793576
A systematic review of the measurement properties of the Body Image Scale (BIS) in cancer patients.
Melissant, Heleen C; Neijenhuijs, Koen I; Jansen, Femke; Aaronson, Neil K; Groenvold, Mogens; Holzner, Bernhard; Terwee, Caroline B; van Uden-Kraan, Cornelia F; Cuijpers, Pim; Verdonck-de Leeuw, Irma M
2018-06-01
Body image is acknowledged as an important aspect of health-related quality of life in cancer patients. The Body Image Scale (BIS) is a patient-reported outcome measure (PROM) to evaluate body image in cancer patients. The aim of this study was to systematically review measurement properties of the BIS among cancer patients. A search in Embase, MEDLINE, PsycINFO, and Web of Science was performed to identify studies that investigated measurement properties of the BIS (Prospero ID 42017057237). Study quality was assessed (excellent, good, fair, poor), and data were extracted and analyzed according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology on structural validity, internal consistency, reliability, measurement error, hypothesis testing for construct validity, and responsiveness. Evidence was categorized into sufficient, insufficient, inconsistent, or indeterminate. Nine studies were included. Evidence was sufficient for structural validity (one factor solution), internal consistency (α = 0.86-0.96), and reliability (r > 0.70); indeterminate for measurement error (information on minimal important change lacked) and responsiveness (increasing body image disturbance in only one study); and inconsistent for hypothesis testing (conflicting results). Quality of the evidence was moderate to low. No studies reported on cross-cultural validity. The BIS is a PROM with good structural validity, internal consistency, and test-retest reliability, but good quality studies on the other measurement properties are needed to optimize evidence. It is recommended to include a wider variety of cancer diagnoses and treatment modalities in these future studies.
Wei, Meifen; Russell, Daniel W; Mallinckrodt, Brent; Vogel, David L
2007-04-01
We developed a 12-item, short form of the Experiences in Close Relationship Scale (ECR; Brennan, Clark, & Shaver, 1998) across 6 studies. In Study 1, we examined the reliability and factor structure of the measure. In Studies 2 and 3, we cross-validated the reliability, factor structure, and validity of the short form measure; whereas in Study 4, we examined test-retest reliability over a 1-month period. In Studies 5 and 6, we further assessed the reliability, factor structure, and validity of the short version of the ECR when administered as a stand-alone instrument. Confirmatory factor analyses indicated that 2 factors, labeled Anxiety and Avoidance, provided a good fit to the data after removing the influence of response sets. We found validity to be equivalent for the short and the original versions of the ECR across studies. Finally, the results were comparable when we embedded the short form within the original version of the ECR and when we administered it as a stand-alone measure.
Reliability of a structured interview for admission to an emergency medicine residency program.
Blouin, Danielle
2010-10-01
Interviews are most important in resident selection. Structured interviews are more reliable than unstructured ones. We sought to measure the interrater reliability of a newly designed structured interview during the selection process to an Emergency Medicine residency program. The critical incident technique was used to extract the desired dimensions of performance. The interview tool consisted of 7 clinical scenarios and 1 global rating. Three trained interviewers marked each candidate on all scenarios without discussing candidates' responses. Interitem consistency and estimates of variance were computed. Twenty-eight candidates were interviewed. The generalizability coefficient was 0.67. Removing the central tendency ratings increased the coefficient to 0.74. Coefficients of interitem consistency ranged from 0.64 to 0.74. The structured interview tool provided good although suboptimal interrater reliability. Increasing the number of scenarios improves reliability as does applying differential weights to the rating scale anchors. The latter would also facilitate the identification of those candidates with extreme ratings.
Structure Learning in Bayesian Sensorimotor Integration
Genewein, Tim; Hez, Eduard; Razzaghpanah, Zeynab; Braun, Daniel A.
2015-01-01
Previous studies have shown that sensorimotor processing can often be described by Bayesian learning, in particular the integration of prior and feedback information depending on its degree of reliability. Here we test the hypothesis that the integration process itself can be tuned to the statistical structure of the environment. We exposed human participants to a reaching task in a three-dimensional virtual reality environment where we could displace the visual feedback of their hand position in a two dimensional plane. When introducing statistical structure between the two dimensions of the displacement, we found that over the course of several days participants adapted their feedback integration process in order to exploit this structure for performance improvement. In control experiments we found that this adaptation process critically depended on performance feedback and could not be induced by verbal instructions. Our results suggest that structural learning is an important meta-learning component of Bayesian sensorimotor integration. PMID:26305797
Oksanen, Esko; Blakeley, Matthew P; El-Hajji, Mohamed; Ryde, Ulf; Budayova-Spano, Monika
2014-01-01
Urate oxidase transforms uric acid to 5-hydroxyisourate without the help of cofactors, but the catalytic mechanism has remained enigmatic, as the protonation state of the substrate could not be reliably deduced. We have determined the neutron structure of urate oxidase, providing unique information on the proton positions. A neutron crystal structure inhibited by a chloride anion at 2.3 Å resolution shows that the substrate is in fact 8-hydroxyxanthine, the enol tautomer of urate. We have also determined the neutron structure of the complex with the inhibitor 8-azaxanthine at 1.9 Å resolution, showing the protonation states of the K10-T57-H256 catalytic triad. Together with X-ray data and quantum chemical calculations, these structures allow us to identify the site of the initial substrate protonation and elucidate why the enzyme is inhibited by a chloride anion.
Brylinski, Michal; Skolnick, Jeffrey
2010-01-01
The rapid accumulation of gene sequences, many of which are hypothetical proteins with unknown function, has stimulated the development of accurate computational tools for protein function prediction with evolution/structure-based approaches showing considerable promise. In this paper, we present FINDSITE-metal, a new threading-based method designed specifically to detect metal binding sites in modeled protein structures. Comprehensive benchmarks using different quality protein structures show that weakly homologous protein models provide sufficient structural information for quite accurate annotation by FINDSITE-metal. Combining structure/evolutionary information with machine learning results in highly accurate metal binding annotations; for protein models constructed by TASSER, whose average Cα RMSD from the native structure is 8.9 Å, 59.5% (71.9%) of the best of top five predicted metal locations are within 4 Å (8 Å) from a bound metal in the crystal structure. For most of the targets, multiple metal binding sites are detected with the best predicted binding site at rank 1 and within the top 2 ranks in 65.6% and 83.1% of the cases, respectively. Furthermore, for iron, copper, zinc, calcium and magnesium ions, the binding metal can be predicted with high, typically 70-90%, accuracy. FINDSITE-metal also provides a set of confidence indexes that help assess the reliability of predictions. Finally, we describe the proteome-wide application of FINDSITE-metal that quantifies the metal binding complement of the human proteome. FINDSITE-metal is freely available to the academic community at http://cssb.biology.gatech.edu/findsite-metal/. PMID:21287609
Speaker-Sex Discrimination for Voiced and Whispered Vowels at Short Durations.
Smith, David R R
2016-01-01
Whispered vowels, produced with no vocal fold vibration, lack the periodic temporal fine structure which in voiced vowels underlies the perceptual attribute of pitch (a salient auditory cue to speaker sex). Voiced vowels possess no temporal fine structure at very short durations (below two glottal cycles). The prediction was that speaker-sex discrimination performance for whispered and voiced vowels would be similar for very short durations but, as stimulus duration increases, voiced vowel performance would improve relative to whispered vowel performance as pitch information becomes available. This pattern of results was shown for women's but not for men's voices. A whispered vowel needs to have a duration three times longer than a voiced vowel before listeners can reliably tell whether it's spoken by a man or woman (∼30 ms vs. ∼10 ms). Listeners were half as sensitive to information about speaker-sex when it is carried by whispered compared with voiced vowels.
Mfold web server for nucleic acid folding and hybridization prediction.
Zuker, Michael
2003-07-01
The abbreviated name, 'mfold web server', describes a number of closely related software applications available on the World Wide Web (WWW) for the prediction of the secondary structure of single stranded nucleic acids. The objective of this web server is to provide easy access to RNA and DNA folding and hybridization software to the scientific community at large. By making use of universally available web GUIs (Graphical User Interfaces), the server circumvents the problem of portability of this software. Detailed output, in the form of structure plots with or without reliability information, single strand frequency plots and 'energy dot plots', are available for the folding of single sequences. A variety of 'bulk' servers give less information, but in a shorter time and for up to hundreds of sequences at once. The portal for the mfold web server is http://www.bioinfo.rpi.edu/applications/mfold. This URL will be referred to as 'MFOLDROOT'.
Introduction of the ASGARD code (Automated Selection and Grouping of events in AIA Regional Data)
NASA Astrophysics Data System (ADS)
Bethge, Christian; Winebarger, Amy; Tiwari, Sanjiv K.; Fayock, Brian
2017-08-01
We have developed the ASGARD code to automatically detect and group brightenings ("events") in AIA data. The event selection and grouping can be optimized to the respective dataset with a multitude of control parameters. The code was initially written for IRIS data, but has since been optimized for AIA. However, the underlying algorithm is not limited to either and could be used for other data as well.Results from datasets in various AIA channels show that brightenings are reliably detected and that coherent coronal structures can be isolated by using the obtained information about the start, peak, and end times of events. We are presently working on a follow-up algorithm to automatically determine the heating and cooling timescales of coronal structures. This will be done by correlating the information from different AIA channels with different temperature responses. We will present the code and preliminary results.
A framework to support human factors of automation in railway intelligent infrastructure.
Dadashi, Nastaran; Wilson, John R; Golightly, David; Sharples, Sarah
2014-01-01
Technological and organisational advances have increased the potential for remote access and proactive monitoring of the infrastructure in various domains and sectors - water and sewage, oil and gas and transport. Intelligent Infrastructure (II) is an architecture that potentially enables the generation of timely and relevant information about the state of any type of infrastructure asset, providing a basis for reliable decision-making. This paper reports an exploratory study to understand the concepts and human factors associated with II in the railway, largely drawing from structured interviews with key industry decision-makers and attachment to pilot projects. Outputs from the study include a data-processing framework defining the key human factors at different levels of the data structure within a railway II system and a system-level representation. The framework and other study findings will form a basis for human factors contributions to systems design elements such as information interfaces and role specifications.
Automated wind load characterization of wind turbine structures by embedded model updating
NASA Astrophysics Data System (ADS)
Swartz, R. Andrew; Zimmerman, Andrew T.; Lynch, Jerome P.
2010-04-01
The continued development of renewable energy resources is for the nation to limit its carbon footprint and to enjoy independence in energy production. Key to that effort are reliable generators of renewable energy sources that are economically competitive with legacy sources. In the area of wind energy, a major contributor to the cost of implementation is large uncertainty regarding the condition of wind turbines in the field due to lack of information about loading, dynamic response, and fatigue life of the structure expended. Under favorable circumstances, this uncertainty leads to overly conservative designs and maintenance schedules. Under unfavorable circumstances, it leads to inadequate maintenance schedules, damage to electrical systems, or even structural failure. Low-cost wireless sensors can provide more certainty for stakeholders by measuring the dynamic response of the structure to loading, estimating the fatigue state of the structure, and extracting loading information from the structural response without the need of an upwind instrumentation tower. This study presents a method for using wireless sensor networks to estimate the spectral properties of a wind turbine tower loading based on its measured response and some rudimentary knowledge of its structure. Structural parameters are estimated via model-updating in the frequency domain to produce an identification of the system. The updated structural model and the measured output spectra are then used to estimate the input spectra. Laboratory results are presented indicating accurate load characterization.
Reichert, Brian E.; Kendall, William L.; Fletcher, Robert J.; Kitchens, Wiley M.
2016-01-01
While variation in age structure over time and space has long been considered important for population dynamics and conservation, reliable estimates of such spatio-temporal variation in age structure have been elusive for wild vertebrate populations. This limitation has arisen because of problems of imperfect detection, the potential for temporary emigration impacting assessments of age structure, and limited information on age. However, identifying patterns in age structure is important for making reliable predictions of both short- and long-term dynamics of populations of conservation concern. Using a multistate superpopulation estimator, we estimated region-specific abundance and age structure (the proportion of individuals within each age class) of a highly endangered population of snail kites for two separate regions in Florida over 17 years (1997–2013). We find that in the southern region of the snail kite—a region known to be critical for the long-term persistence of the species—the population has declined significantly since 1997, and during this time, it has increasingly become dominated by older snail kites (> 12 years old). In contrast, in the northern region—a region historically thought to serve primarily as drought refugia—the population has increased significantly since 2007 and age structure is more evenly distributed among age classes. Given that snail kites show senescence at approximately 13 years of age, where individuals suffer higher mortality rates and lower breeding rates, these results reveal an alarming trend for the southern region. Our work illustrates the importance of accounting for spatial structure when assessing changes in abundance and age distribution and the need for monitoring of age structure in imperiled species.
Structural Probability Concepts Adapted to Electrical Engineering
NASA Technical Reports Server (NTRS)
Steinberg, Eric P.; Chamis, Christos C.
1994-01-01
Through the use of equivalent variable analogies, the authors demonstrate how an electrical subsystem can be modeled by an equivalent structural subsystem. This allows the electrical subsystem to be probabilistically analyzed by using available structural reliability computer codes such as NESSUS. With the ability to analyze the electrical subsystem probabilistically, we can evaluate the reliability of systems that include both structural and electrical subsystems. Common examples of such systems are a structural subsystem integrated with a health-monitoring subsystem, and smart structures. Since these systems have electrical subsystems that directly affect the operation of the overall system, probabilistically analyzing them could lead to improved reliability and reduced costs. The direct effect of the electrical subsystem on the structural subsystem is of secondary order and is not considered in the scope of this work.
Pehora, Carolyne; Gajaria, Nisha; Stoute, Melyssa; Fracassa, Sonia; Serebale-O'Sullivan, Refilwe; Matava, Clyde T
2015-06-22
The use of the Internet to search for medical and health-related information is increasing and associated with concerns around quality and safety. We investigated the current use and perceptions on reliable websites for children's health information by parents. Following institutional ethics approval, we conducted a survey of parents/guardians of children presenting for day surgery. A 20-item survey instrument developed and tested by the investigators was administered. Ninety-eight percent of respondents reported that they used the Internet to search for information about their child's health. Many respondents reported beginning their search at public search engines (80%); less than 20% reported starting their search at university/hospital-based websites. Common conditions such as colds/flu, skin conditions and fever were the most frequently searched, and unique conditions directly affecting the child were second. Despite low usage levels of university/hospital-based websites for health information, the majority of respondents (74%) regarded these as providing safe, accurate, and reliable information. In contrast, only 24% of respondents regarded public search engines as providing safe and reliable information. Fifty percent of respondents reported that they cross-checked information found on the internet with a family physician. An unprecedented majority of parents and guardians are using the Internet for their child's health information. Of concern is that parents and guardians are currently not using reliable and safe sources of information. Health care providers should begin to focus on improving access to safe, accurate, and reliable information through various modalities including education, designing for multiplatform, and better search engine optimization.
Relational, Structural, and Semantic Analysis of Graphical Representations and Concept Maps
ERIC Educational Resources Information Center
Ifenthaler, Dirk
2010-01-01
The demand for good instructional environments presupposes valid and reliable analytical instruments for educational research. This paper introduces the "SMD Technology" (Surface, Matching, Deep Structure), which measures relational, structural, and semantic levels of graphical representations and concept maps. The reliability and validity of the…
Banks, Jamie L; Marotta, Charles A
2007-03-01
The modified Rankin scale (mRS), a clinician-reported measure of global disability, is widely applied for evaluating stroke patient outcomes and as an end point in randomized clinical trials. Extensive evidence on the validity of the mRS exists across a large but fragmented literature. As new treatments for acute ischemic stroke are submitted for agency approval, an appreciation of the mRS's attributes, specifically its relationship to other stroke evaluation scales, would be valuable for decision-makers to properly assess the impact of a new drug on treatment paradigms. The purpose of this report is to assemble and systematically assess the properties of the mRS to provide decision-makers with pertinent evaluative information. A Medline search was conducted to identify reports in the peer-reviewed medical literature (1957-2006) that provide information on the structure, validation, scoring, and psychometric properties of the mRS and its use in clinical trials. The selection of articles was based on defined criteria that included relevance, study design and use of appropriate statistical methods. Of 224 articles identified by the literature search, 50 were selected for detailed assessment. Inter-rater reliability with the mRS is moderate and improves with structured interviews (kappa 0.56 versus 0.78); strong test-re-test reliability (kappa=0.81 to 0.95) has been reported. Numerous studies demonstrate the construct validity of the mRS by its relationships to physiological indicators such as stroke type, lesion size, perfusion and neurological impairment. Convergent validity between the mRS and other disability scales is well documented. Patient comorbidities and socioeconomic factors should be considered in properly applying and interpreting the mRS. Recent analyses suggest that randomized clinical trials of acute stroke treatments may require a smaller sample size if the mRS is used as a primary end point rather than the Barthel Index. Multiple types of evidence attest to the validity and reliability of the mRS. The reported data support the view that the mRS is a valuable instrument for assessing the impact of new stroke treatments.
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Environmental change mediates mate choice for an extended phenotype, but not for mate quality.
Head, Megan L; Fox, Rebecca J; Barber, Iain
2017-01-01
Sexual cues, including extended phenotypes, are expected to be reliable indicators of male genetic quality and/or provide information on parental quality. However, the reliability of these cues may be dependent on stability of the environment, with heterogeneity affecting how selection acts on such traits. Here, we test how environmental change mediates mate choice for multiple sexual traits, including an extended phenotype--the structure of male-built nests - in stickleback fish. First, we manipulated the dissolved oxygen (DO) content of water to create high or low DO environments in which male fish built nests. Then we recorded the mate choice of females encountering these males (and their nests), under either the same or reversed DO conditions. Males in high DO environments built more compact nests than those in low DO conditions and males adjusted their nest structure in response to changing conditions. Female mate choice for extended phenotype (male nests) was environmentally dependent (females chose more compact nests in high DO conditions), while female choice for male phenotype was not (females chose large, vigorous males regardless of DO level). Examining mate choice in this dynamic context suggests that females evaluate the reliability of multiple sexual cues, taking into account environmental heterogeneity. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
Development and Validation of a Self-reported Questionnaire for Measuring Internet Search Dependence
Wang, Yifan; Wu, Lingdan; Zhou, Hongli; Xu, Jiaojing; Dong, Guangheng
2016-01-01
Internet search has become the most common way that people deal with issues and problems in everyday life. The wide use of Internet search has largely changed the way people search for and store information. There is a growing interest in the impact of Internet search on users’ affect, cognition, and behavior. Thus, it is essential to develop a tool to measure the changes in psychological characteristics as a result of long-term use of Internet search. The aim of this study is to develop a Questionnaire on Internet Search Dependence (QISD) and test its reliability and validity. We first proposed a preliminary structure and items of the QISD based on literature review, supplemental investigations, and interviews. And then, we assessed the psychometric properties and explored the factor structure of the initial version via exploratory factor analysis (EFA). The EFA results indicated that four dimensions of the QISD were very reliable, i.e., habitual use of Internet search, withdrawal reaction, Internet search trust, and external storage under Internet search. Finally, we tested the factor solution obtained from EFA through confirmatory factor analysis (CFA). The results of CFA confirmed that the four dimensions model fits the data well. In all, this study suggests that the 12-item QISD is of high reliability and validity and can serve as a preliminary tool to measure the features of Internet search dependence. PMID:28066753
Wang, Yifan; Wu, Lingdan; Zhou, Hongli; Xu, Jiaojing; Dong, Guangheng
2016-01-01
Internet search has become the most common way that people deal with issues and problems in everyday life. The wide use of Internet search has largely changed the way people search for and store information. There is a growing interest in the impact of Internet search on users' affect, cognition, and behavior. Thus, it is essential to develop a tool to measure the changes in psychological characteristics as a result of long-term use of Internet search. The aim of this study is to develop a Questionnaire on Internet Search Dependence (QISD) and test its reliability and validity. We first proposed a preliminary structure and items of the QISD based on literature review, supplemental investigations, and interviews. And then, we assessed the psychometric properties and explored the factor structure of the initial version via exploratory factor analysis (EFA). The EFA results indicated that four dimensions of the QISD were very reliable, i.e., habitual use of Internet search, withdrawal reaction, Internet search trust, and external storage under Internet search. Finally, we tested the factor solution obtained from EFA through confirmatory factor analysis (CFA). The results of CFA confirmed that the four dimensions model fits the data well. In all, this study suggests that the 12-item QISD is of high reliability and validity and can serve as a preliminary tool to measure the features of Internet search dependence.
Magasi, Susan; Wong, Alex; Miskovic, Ana; Tulsky, David; Heinemann, Allen W
2018-01-01
To test the effect that indicators of mobility device quality have on participation outcomes in community-dwelling adults with spinal cord injury, traumatic brain injury, and stroke by using structural equation modeling. Survey, cross-sectional study, and model testing. Clinical research space at 2 academic medical centers and 1 free-standing rehabilitation hospital. Community-dwelling adults (N=250; mean age, 48±14.3y) with spinal cord injury, traumatic brain injury, and stroke. Not applicable. The Mobility Device Impact Scale, Patient-Reported Outcomes Measurement Information System Social Function (version 2.0) scale, including Ability to Participate in Social Roles and Activities and Satisfaction with Social Roles and Activities, and the 2 Community Participation Indicators' enfranchisement scales. Details about device quality (reparability, reliability, ease of maintenance) and device type were also collected. Respondents used ambulation aids (30%), manual (34%), and power wheelchairs (30%). Indicators of device quality had a moderating effect on participation outcomes, with 3 device quality variables (repairability, ease of maintenance, device reliability) accounting for 20% of the variance in participation. Wheelchair users reported lower participation enfranchisement than did ambulation aid users. Mobility device quality plays an important role in participation outcomes. It is critical that people have access to mobility devices and that these devices be reliable. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Patient communication pattern scale: psychometric characteristics.
Ilan, Sara; Carmel, Sara
2016-08-01
In western societies, a shared decision-making model for doctor-patient relationships calling for open and collaborative communication is recommended. Research focuses mainly on the doctor's communication patterns, while research on patient communication patterns is rare. The purpose of this study was to develop a tool for evaluating patient's communication patterns - the Patient Communication Pattern Scale (PCPS). Interviews based on structured questionnaires were conducted with 251 cancer patients. In addition to the 14-item PCPS, the questionnaire included questions regarding education, religiosity and desirability of control in general and over one's own health in particular, for validating the scale. The PCPS was found to be a valid and reliable tool for evaluating patients' communication patterns. Confirmatory factor analysis supported the PCPS designed structure of five facets: (1) Information, (2) Clarification, (3) Initiation, (4) Preferences and (5) Emotions. The PCPS is a reliable scale for evaluating patient communication patterns. The use of this scale can assist in promoting related research and in developing interventions for enhancing open and collaborative doctor-patient communication. © 2015 The Authors. Health Expectations Published by John Wiley & Sons Ltd.
Risk management for the Space Exploration Initiative
NASA Technical Reports Server (NTRS)
Buchbinder, Ben
1993-01-01
Probabilistic Risk Assessment (PRA) is a quantitative engineering process that provides the analytic structure and decision-making framework for total programmatic risk management. Ideally, it is initiated in the conceptual design phase and used throughout the program life cycle. Although PRA was developed for assessment of safety, reliability, and availability risk, it has far greater application. Throughout the design phase, PRA can guide trade-off studies among system performance, safety, reliability, cost, and schedule. These studies are based on the assessment of the risk of meeting each parameter goal, with full consideration of the uncertainties. Quantitative trade-off studies are essential, but without full identification, propagation, and display of uncertainties, poor decisions may result. PRA also can focus attention on risk drivers in situations where risk is too high. For example, if safety risk is unacceptable, the PRA prioritizes the risk contributors to guide the use of resources for risk mitigation. PRA is used in the Space Exploration Initiative (SEI) Program. To meet the stringent requirements of the SEI mission, within strict budgetary constraints, the PRA structure supports informed and traceable decision-making. This paper briefly describes the SEI PRA process.
Network-based statistical comparison of citation topology of bibliographic databases
Šubelj, Lovro; Fiala, Dalibor; Bajec, Marko
2014-01-01
Modern bibliographic databases provide the basis for scientific research and its evaluation. While their content and structure differ substantially, there exist only informal notions on their reliability. Here we compare the topological consistency of citation networks extracted from six popular bibliographic databases including Web of Science, CiteSeer and arXiv.org. The networks are assessed through a rich set of local and global graph statistics. We first reveal statistically significant inconsistencies between some of the databases with respect to individual statistics. For example, the introduced field bow-tie decomposition of DBLP Computer Science Bibliography substantially differs from the rest due to the coverage of the database, while the citation information within arXiv.org is the most exhaustive. Finally, we compare the databases over multiple graph statistics using the critical difference diagram. The citation topology of DBLP Computer Science Bibliography is the least consistent with the rest, while, not surprisingly, Web of Science is significantly more reliable from the perspective of consistency. This work can serve either as a reference for scholars in bibliometrics and scientometrics or a scientific evaluation guideline for governments and research agencies. PMID:25263231
Comparison of Three Information Sources for Smoking Information in Electronic Health Records
Wang, Liwei; Ruan, Xiaoyang; Yang, Ping; Liu, Hongfang
2016-01-01
OBJECTIVE The primary aim was to compare independent and joint performance of retrieving smoking status through different sources, including narrative text processed by natural language processing (NLP), patient-provided information (PPI), and diagnosis codes (ie, International Classification of Diseases, Ninth Revision [ICD-9]). We also compared the performance of retrieving smoking strength information (ie, heavy/light smoker) from narrative text and PPI. MATERIALS AND METHODS Our study leveraged an existing lung cancer cohort for smoking status, amount, and strength information, which was manually chart-reviewed. On the NLP side, smoking-related electronic medical record (EMR) data were retrieved first. A pattern-based smoking information extraction module was then implemented to extract smoking-related information. After that, heuristic rules were used to obtain smoking status-related information. Smoking information was also obtained from structured data sources based on diagnosis codes and PPI. Sensitivity, specificity, and accuracy were measured using patients with coverage (ie, the proportion of patients whose smoking status/strength can be effectively determined). RESULTS NLP alone has the best overall performance for smoking status extraction (patient coverage: 0.88; sensitivity: 0.97; specificity: 0.70; accuracy: 0.88); combining PPI with NLP further improved patient coverage to 0.96. ICD-9 does not provide additional improvement to NLP and its combination with PPI. For smoking strength, combining NLP with PPI has slight improvement over NLP alone. CONCLUSION These findings suggest that narrative text could serve as a more reliable and comprehensive source for obtaining smoking-related information than structured data sources. PPI, the readily available structured data, could be used as a complementary source for more comprehensive patient coverage. PMID:27980387
Thorlund, Kristian; Thabane, Lehana; Mills, Edward J
2013-01-11
Multiple treatment comparison (MTC) meta-analyses are commonly modeled in a Bayesian framework, and weakly informative priors are typically preferred to mirror familiar data driven frequentist approaches. Random-effects MTCs have commonly modeled heterogeneity under the assumption that the between-trial variance for all involved treatment comparisons are equal (i.e., the 'common variance' assumption). This approach 'borrows strength' for heterogeneity estimation across treatment comparisons, and thus, ads valuable precision when data is sparse. The homogeneous variance assumption, however, is unrealistic and can severely bias variance estimates. Consequently 95% credible intervals may not retain nominal coverage, and treatment rank probabilities may become distorted. Relaxing the homogeneous variance assumption may be equally problematic due to reduced precision. To regain good precision, moderately informative variance priors or additional mathematical assumptions may be necessary. In this paper we describe four novel approaches to modeling heterogeneity variance - two novel model structures, and two approaches for use of moderately informative variance priors. We examine the relative performance of all approaches in two illustrative MTC data sets. We particularly compare between-study heterogeneity estimates and model fits, treatment effect estimates and 95% credible intervals, and treatment rank probabilities. In both data sets, use of moderately informative variance priors constructed from the pair wise meta-analysis data yielded the best model fit and narrower credible intervals. Imposing consistency equations on variance estimates, assuming variances to be exchangeable, or using empirically informed variance priors also yielded good model fits and narrow credible intervals. The homogeneous variance model yielded high precision at all times, but overall inadequate estimates of between-trial variances. Lastly, treatment rankings were similar among the novel approaches, but considerably different when compared with the homogenous variance approach. MTC models using a homogenous variance structure appear to perform sub-optimally when between-trial variances vary between comparisons. Using informative variance priors, assuming exchangeability or imposing consistency between heterogeneity variances can all ensure sufficiently reliable and realistic heterogeneity estimation, and thus more reliable MTC inferences. All four approaches should be viable candidates for replacing or supplementing the conventional homogeneous variance MTC model, which is currently the most widely used in practice.
Donahoe, Laura; McDonald, Ellen; Kho, Michelle E; Maclennan, Margaret; Stratford, Paul W; Cook, Deborah J
2009-01-01
Given their clinical, research, and administrative purposes, scores on the Acute Physiology and Chronic Health Evaluation (APACHE) II should be reliable, whether calculated by health care personnel or a clinical information system. To determine reliability of APACHE II scores calculated by a clinical information system and by health care personnel before and after a multifaceted quality improvement intervention. APACHE II scores of 37 consecutive patients admitted to a closed, 15-bed, university-affiliated intensive care unit were collected by a research coordinator, a database clerk, and a clinical information system. After a quality improvement intervention focused on health care personnel and the clinical information system, the same methods were used to collect data on 32 consecutive patients. The research coordinator and the clerk did not know each other's scores or the information system's score. The data analyst did not know the source of the scores until analysis was complete. APACHE II scores obtained by the clerk and the research coordinator were highly reliable (intraclass correlation coefficient, 0.88 before vs 0.80 after intervention; P = .25). No significant changes were detected after the intervention; however, compared with scores of the research coordinator, the overall reliability of APACHE II scores calculated by the clinical information system improved (intraclass correlation coefficient, 0.24 before intervention vs 0.91 after intervention, P < .001). After completion of a quality improvement intervention, health care personnel and a computerized clinical information system calculated sufficiently reliable APACHE II scores for clinical, research, and administrative purposes.
Li, Haibin; He, Yun; Nie, Xiaobo
2018-01-01
Structural reliability analysis under uncertainty is paid wide attention by engineers and scholars due to reflecting the structural characteristics and the bearing actual situation. The direct integration method, started from the definition of reliability theory, is easy to be understood, but there are still mathematics difficulties in the calculation of multiple integrals. Therefore, a dual neural network method is proposed for calculating multiple integrals in this paper. Dual neural network consists of two neural networks. The neural network A is used to learn the integrand function, and the neural network B is used to simulate the original function. According to the derivative relationships between the network output and the network input, the neural network B is derived from the neural network A. On this basis, the performance function of normalization is employed in the proposed method to overcome the difficulty of multiple integrations and to improve the accuracy for reliability calculations. The comparisons between the proposed method and Monte Carlo simulation method, Hasofer-Lind method, the mean value first-order second moment method have demonstrated that the proposed method is an efficient and accurate reliability method for structural reliability problems.
Technical Concept Document. Central Archive for Reusable Defense Software (CARDS)
1994-02-28
FeNbry 1994 INFORMAL TECHNICAL REPORT For The SOFTWARE TECHNOLOGY FOR ADAPTABLE, RELIABLE SYSTEMS (STARS) Technical Concept Document Central Archive for...February 1994 INFORMAL TECHNICAL REPORT For The SOFTWARE TECHNOLOGY FOR ADAPTABLE, RELIABLE SYSTEMS (STARS) Technical Concept Document Central Archive...accordance with the DFARS Special Works Clause Developed by: This document, developed under the Software Technology for Adaptable, Reliable Systems
Large Scale Structure Studies: Final Results from a Rich Cluster Redshift Survey
NASA Astrophysics Data System (ADS)
Slinglend, K.; Batuski, D.; Haase, S.; Hill, J.
1995-12-01
The results from the COBE satellite show the existence of structure on scales on the order of 10% or more of the horizon scale of the universe. Rich clusters of galaxies from the Abell-ACO catalogs show evidence of structure on scales of 100 Mpc and hold the promise of confirming structure on the scale of the COBE result. Unfortunately, until now, redshift information has been unavailable for a large percentage of these clusters, so present knowledge of their three dimensional distribution has quite large uncertainties. Our approach in this effort has been to use the MX multifiber spectrometer on the Steward 2.3m to measure redshifts of at least ten galaxies in each of 88 Abell cluster fields with richness class R>= 1 and mag10 <= 16.8 (estimated z<= 0.12) and zero or one measured redshifts. This work has resulted in a deeper, 95% complete and more reliable sample of 3-D positions of rich clusters. The primary intent of this survey has been to constrain theoretical models for the formation of the structure we see in the universe today through 2-pt. spatial correlation function and other analyses of the large scale structures traced by these clusters. In addition, we have obtained enough redshifts per cluster to greatly improve the quality and size of the sample of reliable cluster velocity dispersions available for use in other studies of cluster properties. This new data has also allowed the construction of an updated and more reliable supercluster candidate catalog. Our efforts have resulted in effectively doubling the volume traced by these clusters. Presented here is the resulting 2-pt. spatial correlation function, as well as density plots and several other figures quantifying the large scale structure from this much deeper and complete sample. Also, with 10 or more redshifts in most of our cluster fields, we have investigated the extent of projection effects within the Abell catalog in an effort to quantify and understand how this may effect the Abell sample.
Probability interpretations of intraclass reliabilities.
Ellis, Jules L
2013-11-20
Research where many organizations are rated by different samples of individuals such as clients, patients, or employees frequently uses reliabilities computed from intraclass correlations. Consumers of statistical information, such as patients and policy makers, may not have sufficient background for deciding which levels of reliability are acceptable. It is shown that the reliability is related to various probabilities that may be easier to understand, for example, the proportion of organizations that will be classed significantly above (or below) the mean and the probability that an organization is classed correctly given that it is classed significantly above (or below) the mean. One can view these probabilities as the amount of information of the classification and the correctness of the classification. These probabilities have an inverse relationship: given a reliability, one can 'buy' correctness at the cost of informativeness and conversely. This article discusses how this can be used to make judgments about the required level of reliabilities. Copyright © 2013 John Wiley & Sons, Ltd.
Health search engine with e-document analysis for reliable search results.
Gaudinat, Arnaud; Ruch, Patrick; Joubert, Michel; Uziel, Philippe; Strauss, Anne; Thonnet, Michèle; Baud, Robert; Spahni, Stéphane; Weber, Patrick; Bonal, Juan; Boyer, Celia; Fieschi, Marius; Geissbuhler, Antoine
2006-01-01
After a review of the existing practical solution available to the citizen to retrieve eHealth document, the paper describes an original specialized search engine WRAPIN. WRAPIN uses advanced cross lingual information retrieval technologies to check information quality by synthesizing medical concepts, conclusions and references contained in the health literature, to identify accurate, relevant sources. Thanks to MeSH terminology [1] (Medical Subject Headings from the U.S. National Library of Medicine) and advanced approaches such as conclusion extraction from structured document, reformulation of the query, WRAPIN offers to the user a privileged access to navigate through multilingual documents without language or medical prerequisites. The results of an evaluation conducted on the WRAPIN prototype show that results of the WRAPIN search engine are perceived as informative 65% (59% for a general-purpose search engine), reliable and trustworthy 72% (41% for the other engine) by users. But it leaves room for improvement such as the increase of database coverage, the explanation of the original functionalities and an audience adaptability. Thanks to evaluation outcomes, WRAPIN is now in exploitation on the HON web site (http://www.healthonnet.org), free of charge. Intended to the citizen it is a good alternative to general-purpose search engines when the user looks up trustworthy health and medical information or wants to check automatically a doubtful content of a Web page.
Probabilistic Finite Element Analysis & Design Optimization for Structural Designs
NASA Astrophysics Data System (ADS)
Deivanayagam, Arumugam
This study focuses on implementing probabilistic nature of material properties (Kevlar® 49) to the existing deterministic finite element analysis (FEA) of fabric based engine containment system through Monte Carlo simulations (MCS) and implementation of probabilistic analysis in engineering designs through Reliability Based Design Optimization (RBDO). First, the emphasis is on experimental data analysis focusing on probabilistic distribution models which characterize the randomness associated with the experimental data. The material properties of Kevlar® 49 are modeled using experimental data analysis and implemented along with an existing spiral modeling scheme (SMS) and user defined constitutive model (UMAT) for fabric based engine containment simulations in LS-DYNA. MCS of the model are performed to observe the failure pattern and exit velocities of the models. Then the solutions are compared with NASA experimental tests and deterministic results. MCS with probabilistic material data give a good prospective on results rather than a single deterministic simulation results. The next part of research is to implement the probabilistic material properties in engineering designs. The main aim of structural design is to obtain optimal solutions. In any case, in a deterministic optimization problem even though the structures are cost effective, it becomes highly unreliable if the uncertainty that may be associated with the system (material properties, loading etc.) is not represented or considered in the solution process. Reliable and optimal solution can be obtained by performing reliability optimization along with the deterministic optimization, which is RBDO. In RBDO problem formulation, in addition to structural performance constraints, reliability constraints are also considered. This part of research starts with introduction to reliability analysis such as first order reliability analysis, second order reliability analysis followed by simulation technique that are performed to obtain probability of failure and reliability of structures. Next, decoupled RBDO procedure is proposed with a new reliability analysis formulation with sensitivity analysis, which is performed to remove the highly reliable constraints in the RBDO, thereby reducing the computational time and function evaluations. Followed by implementation of the reliability analysis concepts and RBDO in finite element 2D truss problems and a planar beam problem are presented and discussed.
Critically re-evaluating a common technique
Geisbush, Thomas; Jones, Lyell; Weiss, Michael; Mozaffar, Tahseen; Gronseth, Gary; Rutkove, Seward B.
2016-01-01
Objectives: (1) To assess the diagnostic accuracy of EMG in radiculopathy. (2) To evaluate the intrarater reliability and interrater reliability of EMG in radiculopathy. (3) To assess the presence of confirmation bias in EMG. Methods: Three experienced academic electromyographers interpreted 3 compact discs with 20 EMG videos (10 normal, 10 radiculopathy) in a blinded, standardized fashion without information regarding the nature of the study. The EMGs were interpreted 3 times (discs A, B, C) 1 month apart. Clinical information was provided only with disc C. Intrarater reliability was calculated by comparing interpretations in discs A and B, interrater reliability by comparing interpretation between reviewers. Confirmation bias was estimated by the difference in correct interpretations when clinical information was provided. Results: Sensitivity was similar to previous reports (77%, confidence interval [CI] 63%–90%); specificity was 71%, CI 56%–85%. Intrarater reliability was good (κ 0.61, 95% CI 0.41–0.81); interrater reliability was lower (κ 0.53, CI 0.35–0.71). There was no substantial confirmation bias when clinical information was provided (absolute difference in correct responses 2.2%, CI −13.3% to 17.7%); the study lacked precision to exclude moderate confirmation bias. Conclusions: This study supports that (1) serial EMG studies should be performed by the same electromyographer since intrarater reliability is better than interrater reliability; (2) knowledge of clinical information does not bias EMG interpretation substantially; (3) EMG has moderate diagnostic accuracy for radiculopathy with modest specificity and electromyographers should exercise caution interpreting mild abnormalities. Classification of evidence: This study provides Class III evidence that EMG has moderate diagnostic accuracy and specificity for radiculopathy. PMID:26701380
Validation of the Mobile Information Software Evaluation Tool (MISET) With Nursing Students.
Secco, M Loretta; Furlong, Karen E; Doyle, Glynda; Bailey, Judy
2016-07-01
This study evaluated the Mobile Information Software Evaluation Tool (MISET) with a sample of Canadian undergraduate nursing students (N = 240). Psychometric analyses determined how well the MISET assessed the extent that nursing students find mobile device-based information resources useful and supportive of learning in the clinical and classroom settings. The MISET has a valid three-factor structure with high explained variance (74.7%). Internal consistency reliabilities were high for the MISET total (.90) and three subscales: Usefulness/Helpfulness, Information Literacy Support, and Use of Evidence-Based Sources (.87 to .94). Construct validity evidence included significantly higher mean total MISET, Helpfulness/Usefulness, and Information Literacy Support scores for senior students and those with higher computer competence. The MISET is a promising tool to evaluate mobile information technologies and information literacy support; however, longitudinal assessment of changes in scores over time would determine scale sensitivity and responsiveness. [J Nurs Educ. 2016;55(7):385-390.]. Copyright 2016, SLACK Incorporated.
Science and Technology Review June 2000
DOE Office of Scientific and Technical Information (OSTI.GOV)
de Pruneda, J.H.
2000-06-01
This issue contains the following articles: (1) ''Accelerating on the ASCI Challenge''. (2) ''New Day Daws in Supercomputing'' When the ASCI White supercomputer comes online this summer, DOE's Stockpile Stewardship Program will make another significant advanced toward helping to ensure the safety, reliability, and performance of the nation's nuclear weapons. (3) ''Uncovering the Secrets of Actinides'' Researchers are obtaining fundamental information about the actinides, a group of elements with a key role in nuclear weapons and fuels. (4) ''A Predictable Structure for Aerogels''. (5) ''Tibet--Where Continents Collide''.
An Overview of Enzymatic Reagents for the Removal of Affinity Tags
Waugh, David S.
2011-01-01
Although they are often exploited to facilitate the expression and purification of recombinant proteins, every affinity tag, whether large or small, has the potential to interfere with the structure and function of its fusion partner. For this reason, reliable methods for removing affinity tags are needed. Only enzymes have the requisite specificity to be generally useful reagents for this purpose. In this review, the advantages and disadvantages of some commonly used endo- and exoproteases are discussed in light of the latest information. PMID:21871965
Sensor Technology for Integrated Vehicle Health Management of Aerospace Vehicles
NASA Technical Reports Server (NTRS)
Prosser, W. H.; Brown, T. L.; Woodard, S. E.; Fleming, G. A.; Cooper, E. G.
2002-01-01
NASA is focusing considerable efforts on technology development for Integrated Vehicle Health Management systems. The research in this area is targeted toward increasing aerospace vehicle safety and reliability, while reducing vehicle operating and maintenance costs. Onboard, real-time sensing technologies that can provide detailed information on structural integrity are central to such a health management system. This paper describes a number of sensor technologies currently under development for integrated vehicle health management. The capabilities, current limitations, and future research needs of these technologies are addressed.
Kyte, Derek; Cockwell, Paul; Marshall, Tom; Gheorghe, Adrian; Keeley, Thomas; Slade, Anita; Calvert, Melanie
2017-01-01
Background Patient-reported outcome measures (PROMs) can provide valuable information which may assist with the care of patients with chronic kidney disease (CKD). However, given the large number of measures available, it is unclear which PROMs are suitable for use in research or clinical practice. To address this we comprehensively evaluated studies that assessed the measurement properties of PROMs in adults with CKD. Methods Four databases were searched; reference list and citation searching of included studies was also conducted. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was used to appraise the methodological quality of the included studies and to inform a best evidence synthesis for each PROM. Results The search strategy retrieved 3,702 titles/abstracts. After 288 duplicates were removed, 3,414 abstracts were screened and 71 full-text articles were retrieved for further review. Of these, 24 full-text articles were excluded as they did not meet the eligibility criteria. Following reference list and citation searching, 19 articles were retrieved bringing the total number of papers included in the final analysis to 66. There was strong evidence supporting internal consistency and moderate evidence supporting construct validity for the Kidney Disease Quality of Life-36 (KDQOL-36) in pre-dialysis patients. In the dialysis population, the KDQOL-Short Form (KDQOL-SF) had strong evidence for internal consistency and structural validity and moderate evidence for test-retest reliability and construct validity while the KDQOL-36 had moderate evidence of internal consistency, test-retest reliability and construct validity. The End Stage Renal Disease-Symptom Checklist Transplantation Module (ESRD-SCLTM) demonstrated strong evidence for internal consistency and moderate evidence for test-retest reliability, structural and construct validity in renal transplant recipients. Conclusions We suggest considering the KDQOL-36 for use in pre-dialysis patients; the KDQOL-SF or KDQOL-36 for dialysis patients and the ESRD-SCLTM for use in transplant recipients. However, further research is required to evaluate the measurement error, structural validity, responsiveness and patient acceptability of PROMs used in CKD. PMID:28636678
Jansen, Femke; Witte, Birgit I; van Uden-Kraan, Cornelia F; Braspenning, Anna M; Leemans, C René; Verdonck-de Leeuw, Irma M
2016-11-01
The purpose of this study is to assess the psychometric properties of the Dutch version of the 34-item Short-Form Supportive Care Needs Survey (SCNS-SF34) and the newly developed module for head and neck cancer (HNC) patients (SCNS-HNC). HNC patients were included from two cross-sectional studies. Content validity of the SCNS-HNC was analysed by examining redundancy and completeness of items. Factor structure was assessed using confirmatory and exploratory factor analyses. Cronbach's alpha, Spearman's correlation, Mann-Whitney U test, Kruskall-Wallis and intraclass correlation coefficients (ICC) were used to assess internal consistency, construct validity and test-retest reliability. Content validity of the SCNS-HNC was good, although some HNC topics were missing. For the SCNS-SF34, a four-factor structure was found, namely physical and daily living, psychological, sexuality and health system and information and patient support (alpha = .79 to .95). For the SCNS-HNC, a two-factor structure was found, namely HNC-specific functioning and lifestyle (alpha = .89 and .60). Respectively, 96 and 89 % of the hypothesised correlations between the SCNS-SF34 or SCNS-HNC and other patient-reported outcome measures were found; 57 and 67 % also showed the hypothesised magnitude of correlation. The SCNS-SF34 domains discriminated between treatment procedure (physical and daily living p = .02 and psychological p = .01) and time since treatment (health system, information and patient support p = .02). Test-retest reliability of SCNS-SF34 domains and HNC-specific functioning domain was above .70 (ICC = .74 to .83), and ICC = .67 for the lifestyle domain. Floor effects ranged from 21.1 to 70.9 %. The SCNS-SF34 and SCNS-HNC are valid and reliable instruments to evaluate the need for supportive care among (Dutch) HNC patients.
NASA Astrophysics Data System (ADS)
Fan, Xiao-Ning; Zhi, Bo
2017-07-01
Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO) offers a more reasonable design approach. However, existing RBDO methods for crane metallic structures are prone to low convergence speed and high computational cost. A unilevel RBDO method, combining a discrete imperialist competitive algorithm with an inverse reliability strategy based on the performance measure approach, is developed. Application of the imperialist competitive algorithm at the optimization level significantly improves the convergence speed of this RBDO method. At the reliability analysis level, the inverse reliability strategy is used to determine the feasibility of each probabilistic constraint at each design point by calculating its α-percentile performance, thereby avoiding convergence failure, calculation error, and disproportionate computational effort encountered using conventional moment and simulation methods. Application of the RBDO method to an actual crane structure shows that the developed RBDO realizes a design with the best tradeoff between economy and safety together with about one-third of the convergence speed and the computational cost of the existing method. This paper provides a scientific and effective design approach for the design of metallic structures of cranes.
Evaluating information skills training in health libraries: a systematic review.
Brettle, Alison
2007-12-01
Systematic reviews have shown that there is limited evidence to demonstrate that the information literacy training health librarians provide is effective in improving clinicians' information skills or has an impact on patient care. Studies lack measures which demonstrate validity and reliability in evaluating the impact of training. To determine what measures have been used; the extent to which they are valid and reliable; to provide guidance for health librarians who wish to evaluate the impact of their information skills training. Systematic review methodology involved searching seven databases, and personal files. Studies were included if they were about information skills training, used an objective measure to assess outcomes, and occurred in a health setting. Fifty-four studies were included in the review. Most outcome measures used in the studies were not tested for the key criteria of validity and reliability. Three tested for validity and reliability are described in more detail. Selecting an appropriate measure to evaluate the impact of training is a key factor in carrying out any evaluation. This systematic review provides guidance to health librarians by highlighting measures used in various circumstances, and those that demonstrate validity and reliability.
O'Reilly, Robert; Fedorko, Steve; Nicholson, Nigel
1983-01-01
This paper describes a structured interview process for medical school admissions supported by an Apple II computer system which provides feedback to interviewers and the College admissions committee. Presented are the rationale for the system, the preliminary results of analysis of some of the interview data, and a brief description of the computer program and output. The present data show that the structured interview yields very high interrater reliability coefficients, is acceptable to the medical school faculty, and results in quantitative data useful in the admission process. The system continues in development at this time, a second year of data will be shortly available, and further refinements are being made to the computer program to enhance its utilization and exportability.
Coherent diffraction imaging: consistency of the assembled three-dimensional distribution.
Tegze, Miklós; Bortel, Gábor
2016-07-01
The short pulses of X-ray free-electron lasers can produce diffraction patterns with structural information before radiation damage destroys the particle. From the recorded diffraction patterns the structure of particles or molecules can be determined on the nano- or even atomic scale. In a coherent diffraction imaging experiment thousands of diffraction patterns of identical particles are recorded and assembled into a three-dimensional distribution which is subsequently used to solve the structure of the particle. It is essential to know, but not always obvious, that the assembled three-dimensional reciprocal-space intensity distribution is really consistent with the measured diffraction patterns. This paper shows that, with the use of correlation maps and a single parameter calculated from them, the consistency of the three-dimensional distribution can be reliably validated.
Probabilistic load simulation: Code development status
NASA Astrophysics Data System (ADS)
Newell, J. F.; Ho, H.
1991-05-01
The objective of the Composite Load Spectra (CLS) project is to develop generic load models to simulate the composite load spectra that are included in space propulsion system components. The probabilistic loads thus generated are part of the probabilistic design analysis (PDA) of a space propulsion system that also includes probabilistic structural analyses, reliability, and risk evaluations. Probabilistic load simulation for space propulsion systems demands sophisticated probabilistic methodology and requires large amounts of load information and engineering data. The CLS approach is to implement a knowledge based system coupled with a probabilistic load simulation module. The knowledge base manages and furnishes load information and expertise and sets up the simulation runs. The load simulation module performs the numerical computation to generate the probabilistic loads with load information supplied from the CLS knowledge base.
Zarrinabadi, Zarrin; Isfandyari-Moghaddam, Alireza; Erfani, Nasrolah; Tahour Soltani, Mohsen Ahmadi
2018-01-01
INTRODUCTION: According to the research mission of the librarianship and information sciences field, it is necessary to have the ability to communicate constructively between the user of the information and information in these students, and it appears more important in medical librarianship and information sciences because of the need for quick access to information for clinicians. Considering the role of spiritual intelligence in capability to establish effective and balanced communication makes it important to study this variable in librarianship and information students. One of the main factors that can affect the results of any research is conceptual model of measure variables. Accordingly, the purpose of this study was codification of spiritual intelligence measurement model. METHODS: This correlational study was conducted through structural equation model, and 270 students were opted from library and medical information students of nationwide medical universities by simple random sampling and responded to the King spiritual intelligence questionnaire (2008). Initially, based on the data, the model parameters were estimated using maximum likelihood method; then, spiritual intelligence measurement model was tested by fit indices. Data analysis was performed by Smart-Partial Least Squares software. RESULTS: Preliminary results showed that due to the positive indicators of predictive association and t-test results for spiritual intelligence parameters, the King measurement model has the acceptable fit and internal correlation of the questionnaire items was significant. Composite reliability and Cronbach's alpha of parameters indicated high reliability of spiritual intelligence model. CONCLUSIONS: The spiritual intelligence measurement model was evaluated, and results showed that the model has a good fit, so it is recommended that domestic researchers use this questionnaire to assess spiritual intelligence. PMID:29922688
Zarrinabadi, Zarrin; Isfandyari-Moghaddam, Alireza; Erfani, Nasrolah; Tahour Soltani, Mohsen Ahmadi
2018-01-01
According to the research mission of the librarianship and information sciences field, it is necessary to have the ability to communicate constructively between the user of the information and information in these students, and it appears more important in medical librarianship and information sciences because of the need for quick access to information for clinicians. Considering the role of spiritual intelligence in capability to establish effective and balanced communication makes it important to study this variable in librarianship and information students. One of the main factors that can affect the results of any research is conceptual model of measure variables. Accordingly, the purpose of this study was codification of spiritual intelligence measurement model. This correlational study was conducted through structural equation model, and 270 students were opted from library and medical information students of nationwide medical universities by simple random sampling and responded to the King spiritual intelligence questionnaire (2008). Initially, based on the data, the model parameters were estimated using maximum likelihood method; then, spiritual intelligence measurement model was tested by fit indices. Data analysis was performed by Smart-Partial Least Squares software. Preliminary results showed that due to the positive indicators of predictive association and t -test results for spiritual intelligence parameters, the King measurement model has the acceptable fit and internal correlation of the questionnaire items was significant. Composite reliability and Cronbach's alpha of parameters indicated high reliability of spiritual intelligence model. The spiritual intelligence measurement model was evaluated, and results showed that the model has a good fit, so it is recommended that domestic researchers use this questionnaire to assess spiritual intelligence.
Scale for positive aspects of caregiving experience: development, reliability, and factor structure.
Kate, N; Grover, S; Kulhara, P; Nehra, R
2012-06-01
OBJECTIVE. To develop an instrument (Scale for Positive Aspects of Caregiving Experience [SPACE]) that evaluates positive caregiving experience and assess its psychometric properties. METHODS. Available scales which assess some aspects of positive caregiving experience were reviewed and a 50-item questionnaire with a 5-point rating was constructed. In all, 203 primary caregivers of patients with severe mental disorders were asked to complete the questionnaire. Internal consistency, test-retest reliability, cross-language reliability, split-half reliability, and face validity were evaluated. Principal component factor analysis was run to assess the factorial validity of the scale. RESULTS. The scale developed as part of the study was found to have good internal consistency, test-retest reliability, cross-language reliability, split-half reliability, and face validity. Principal component factor analysis yielded a 4-factor structure, which also had good test-retest reliability and cross-language reliability. There was a strong correlation between the 4 factors obtained. CONCLUSION. The SPACE developed as part of this study has good psychometric properties.
Optimal periodic proof test based on cost-effective and reliability criteria
NASA Technical Reports Server (NTRS)
Yang, J.-N.
1976-01-01
An exploratory study for the optimization of periodic proof tests for fatigue-critical structures is presented. The optimal proof load level and the optimal number of periodic proof tests are determined by minimizing the total expected (statistical average) cost, while the constraint on the allowable level of structural reliability is satisfied. The total expected cost consists of the expected cost of proof tests, the expected cost of structures destroyed by proof tests, and the expected cost of structural failure in service. It is demonstrated by numerical examples that significant cost saving and reliability improvement for fatigue-critical structures can be achieved by the application of the optimal periodic proof test. The present study is relevant to the establishment of optimal maintenance procedures for fatigue-critical structures.
A systematic review of the factor structure and reliability of the Spence Children's Anxiety Scale.
Orgilés, Mireia; Fernández-Martínez, Iván; Guillén-Riquelme, Alejandro; Espada, José P; Essau, Cecilia A
2016-01-15
The Spence Children's Anxiety Scale (SCAS) is a widely used instrument for assessing symptoms of anxiety disorders among children and adolescents. Previous studies have demonstrated its good reliability for children and adolescents from different backgrounds. However, remarkable variability in the reliability of the SCAS across studies and inconsistent results regarding its factor structure has been found. The present study aims to examine the SCAS factor structure by means of a systematic review with narrative synthesis, the mean reliability of the SCAS by means of a meta-analysis, and the influence of the moderators on the SCAS reliability. Databases employed to collect the studies included Scholar Google, PsycARTICLES, PsycINFO, Web of Science, and Scopus since 1997. Twenty-nine and 32 studies, which examined the factor structure and the internal consistency of the SCAS, respectively, were included. The SCAS was found to have strong internal consistency, influenced by different moderators. The systematic review demonstrated that the original six-factor model was supported by most studies. Factorial invariance studies (across age, gender, country) and test-retest reliability of the SCAS were not examined in this study. It is concluded that the SCAS is a reliable instrument for cross-cultural use, and it is suggested that the original six-factor model is appropriate for cross-cultural application. Copyright © 2015 Elsevier B.V. All rights reserved.
Reliability-Based Design Optimization of a Composite Airframe Component
NASA Technical Reports Server (NTRS)
Patnaik, Surya N.; Pai, Shantaram S.; Coroneos, Rula M.
2009-01-01
A stochastic design optimization methodology (SDO) has been developed to design components of an airframe structure that can be made of metallic and composite materials. The design is obtained as a function of the risk level, or reliability, p. The design method treats uncertainties in load, strength, and material properties as distribution functions, which are defined with mean values and standard deviations. A design constraint or a failure mode is specified as a function of reliability p. Solution to stochastic optimization yields the weight of a structure as a function of reliability p. Optimum weight versus reliability p traced out an inverted-S-shaped graph. The center of the inverted-S graph corresponded to 50 percent (p = 0.5) probability of success. A heavy design with weight approaching infinity could be produced for a near-zero rate of failure that corresponds to unity for reliability p (or p = 1). Weight can be reduced to a small value for the most failure-prone design with a reliability that approaches zero (p = 0). Reliability can be changed for different components of an airframe structure. For example, the landing gear can be designed for a very high reliability, whereas it can be reduced to a small extent for a raked wingtip. The SDO capability is obtained by combining three codes: (1) The MSC/Nastran code was the deterministic analysis tool, (2) The fast probabilistic integrator, or the FPI module of the NESSUS software, was the probabilistic calculator, and (3) NASA Glenn Research Center s optimization testbed CometBoards became the optimizer. The SDO capability requires a finite element structural model, a material model, a load model, and a design model. The stochastic optimization concept is illustrated considering an academic example and a real-life raked wingtip structure of the Boeing 767-400 extended range airliner made of metallic and composite materials.
Vaccari, L; Birarda, G; Businaro, L; Pacor, S; Grenci, G
2012-06-05
Until nowadays most infrared microspectroscopy (IRMS) experiments on biological specimens (i.e., tissues or cells) have been routinely carried out on fixed or dried samples in order to circumvent water absorption problems. In this paper, we demonstrate the possibility to widen the range of in-vitro IRMS experiments to vibrational analysis of live cellular samples, thanks to the development of novel biocompatible IR-visible transparent microfluidic devices (MD). In order to highlight the biological relevance of IRMS in MD (MD-IRMS), we performed a systematic exploration of the biochemical alterations induced by different fixation protocols, ethanol 70% and formaldehyde solution 4%, as well as air-drying on U937 leukemic monocytes by comparing their IR vibrational features with the live U937 counterpart. Both fixation and air-drying procedures affected lipid composition and order as well as protein structure at a different extent while they both induced structural alterations in nucleic acids. Therefore, only IRMS of live cells can provide reliable information on both DNA and RNA structure and on their cellular dynamic. In summary, we show that MD-IRMS of live cells is feasible, reliable, and biologically relevant to be recognized as a label-free cell-based assay.
Applying Gradient Descent in Convolutional Neural Networks
NASA Astrophysics Data System (ADS)
Cui, Nan
2018-04-01
With the development of the integrated circuit and computer science, people become caring more about solving practical issues via information technologies. Along with that, a new subject called Artificial Intelligent (AI) comes up. One popular research interest of AI is about recognition algorithm. In this paper, one of the most common algorithms, Convolutional Neural Networks (CNNs) will be introduced, for image recognition. Understanding its theory and structure is of great significance for every scholar who is interested in this field. Convolution Neural Network is an artificial neural network which combines the mathematical method of convolution and neural network. The hieratical structure of CNN provides it reliable computer speed and reasonable error rate. The most significant characteristics of CNNs are feature extraction, weight sharing and dimension reduction. Meanwhile, combining with the Back Propagation (BP) mechanism and the Gradient Descent (GD) method, CNNs has the ability to self-study and in-depth learning. Basically, BP provides an opportunity for backwardfeedback for enhancing reliability and GD is used for self-training process. This paper mainly discusses the CNN and the related BP and GD algorithms, including the basic structure and function of CNN, details of each layer, the principles and features of BP and GD, and some examples in practice with a summary in the end.
Impact of clinical history on chest radiograph interpretation.
Test, Matthew; Shah, Samir S; Monuteaux, Michael; Ambroggio, Lilliam; Lee, Edward Y; Markowitz, Richard I; Bixby, Sarah; Diperna, Stephanie; Servaes, Sabah; Hellinger, Jeffrey C; Neuman, Mark I
2013-07-01
The inclusion of clinical information may have unrecognized influence in the interpretation of diagnostic testing. The objective of the study was to determine the impact of clinical history on chest radiograph interpretation in the diagnosis of pneumonia. Prospective case-based study. Radiologists interpreted 110 radiographs of children evaluated for suspicion of pneumonia. Clinical information was withheld during the first interpretation. After 6 months the radiographs were reviewed with clinical information. Radiologists reported on pneumonia indicators described by the World Health Organization (ie, any infiltrate, alveolar infiltrate, interstitial infiltrate, air bronchograms, hilar adenopathy, pleural effusion). Children's Hospital of Philadelphia and Boston Children's Hospital. Six board-certified radiologists. Inter- and inter-rater reliability were assessed using the kappa statistic. The addition of clinical history did not have a substantial impact on the inter-rater reliability in the identification of any infiltrate, alveolar infiltrate, interstitial infiltrate, pleural effusion, or hilar adenopathy. Inter-rater reliability in the identification of air bronchograms improved from fair (k = 0.32) to moderate (k = 0.53). Intra-rater reliability for the identification of alveolar infiltrate remained substantial to almost perfect for all 6 raters with and without clinical information. One rater had a decrease in inter-rater reliability from almost perfect (k = 1.0) to fair (k = 0.21) in the identification of interstitial infiltrate with the addition of clinical history. Alveolar infiltrate and pleural effusion are findings with high intra- and inter-rater reliability in the diagnosis of bacterial pneumonia. The addition of clinical information did not have a substantial impact on the reliability of these findings. © 2012 Society of Hospital Medicine.
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.
NASA Astrophysics Data System (ADS)
Tsutsumi, Shigeyoshi; Wada, Takahiro; Akita, Tokihiko; Doi, Shun'ichi
Driver's workload tends to be increased during driving under complicated traffic environments like a lane change. In such cases, rear collision warning is effective for reduction of cognitive workload. On the other hand, it is pointed out that false alarm or missing alarm caused by sensor errors leads to decrease of driver' s trust in the warning system and it can result in low efficiency of the system. Suppose that reliability information of the sensor is provided in real-time. In this paper, we propose a new warning method to increase driver' s trust in the system even with low sensor reliability utilizing the sensor reliability information. The effectiveness of the warning methods is shown by driving simulator experiments.
NASA Technical Reports Server (NTRS)
Sobel, Larry; Buttitta, Claudio; Suarez, James
1993-01-01
Probabilistic predictions based on the Integrated Probabilistic Assessment of Composite Structures (IPACS) code are presented for the material and structural response of unnotched and notched, 1M6/3501-6 Gr/Ep laminates. Comparisons of predicted and measured modulus and strength distributions are given for unnotched unidirectional, cross-ply, and quasi-isotropic laminates. The predicted modulus distributions were found to correlate well with the test results for all three unnotched laminates. Correlations of strength distributions for the unnotched laminates are judged good for the unidirectional laminate and fair for the cross-ply laminate, whereas the strength correlation for the quasi-isotropic laminate is deficient because IPACS did not yet have a progressive failure capability. The paper also presents probabilistic and structural reliability analysis predictions for the strain concentration factor (SCF) for an open-hole, quasi-isotropic laminate subjected to longitudinal tension. A special procedure was developed to adapt IPACS for the structural reliability analysis. The reliability results show the importance of identifying the most significant random variables upon which the SCF depends, and of having accurate scatter values for these variables.
Bayesian Meta-Analysis of Cronbach's Coefficient Alpha to Evaluate Informative Hypotheses
ERIC Educational Resources Information Center
Okada, Kensuke
2015-01-01
This paper proposes a new method to evaluate informative hypotheses for meta-analysis of Cronbach's coefficient alpha using a Bayesian approach. The coefficient alpha is one of the most widely used reliability indices. In meta-analyses of reliability, researchers typically form specific informative hypotheses beforehand, such as "alpha of…
NASA Astrophysics Data System (ADS)
Balducci, G.; Bencivenni, L.; De Rosa, G.; Gigli, R.; Martine, B.; Cesaro, S. Nunziante
1980-05-01
The infrared and Raman spectra of some cyclopentadienyl compounds of the transition metals, namely Ti(C 5H 5)Cl 3 and M(C 5H 5) 2Cl 2 (M = Ti, Zr and Hf), are reported and discussed. The infrared spectra of the gaseous species isolated in argon matrices at 10 K provide structural information about the single molecules. Particular attention has been paid to the low-frequency region in order to achieve more reliable assignments for the internal-rotation modes. The structural data and the fundamental frequencies derived from the spectra are employed in a calculation of the thermodynamic functions for these compounds in the ideal gas state.
Proof of Concept of Impact Detection in Composites Using Fiber Bragg Grating Arrays
Gomez, Javier; Jorge, Iagoba; Durana, Gaizka; Arrue, Jon; Zubia, Joseba; Aranguren, Gerardo; Montero, Ander; López, Ion
2013-01-01
Impact detection in aeronautical structures allows predicting their future reliability and performance. An impact can produce microscopic fissures that could evolve into fractures or even the total collapse of the structure, so it is important to know the location and severity of each impact. For this purpose, optical fibers with Bragg gratings are used to analyze each impact and the vibrations generated by them. In this paper it is proven that optical fibers with Bragg gratings can be used to detect impacts, and also that a high-frequency interrogator is necessary to collect valuable information about the impacts. The use of two interrogators constitutes the main novelty of this paper. PMID:24021969
interest: mechanical system design sensitivity analysis and optimization of linear and nonlinear structural systems, reliability analysis and reliability-based design optimization, computational methods in committee member, ISSMO; Associate Editor, Mechanics Based Design of Structures and Machines; Associate
NASA Technical Reports Server (NTRS)
Rais-Rohani, Masoud
2001-01-01
This report describes the preliminary results of an investigation on component reliability analysis and reliability-based design optimization of thin-walled circular composite cylinders with average diameter and average length of 15 inches. Structural reliability is based on axial buckling strength of the cylinder. Both Monte Carlo simulation and First Order Reliability Method are considered for reliability analysis with the latter incorporated into the reliability-based structural optimization problem. To improve the efficiency of reliability sensitivity analysis and design optimization solution, the buckling strength of the cylinder is estimated using a second-order response surface model. The sensitivity of the reliability index with respect to the mean and standard deviation of each random variable is calculated and compared. The reliability index is found to be extremely sensitive to the applied load and elastic modulus of the material in the fiber direction. The cylinder diameter was found to have the third highest impact on the reliability index. Also the uncertainty in the applied load, captured by examining different values for its coefficient of variation, is found to have a large influence on cylinder reliability. The optimization problem for minimum weight is solved subject to a design constraint on element reliability index. The methodology, solution procedure and optimization results are included in this report.
Schrimshaw, Eric W.; Rosario, Margaret; Meyer-Bahlburg, Heino F. L.; Scharf-Matlick, Alice A.
2011-01-01
Despite the importance of reliable self-reported sexual information for research on sexuality and sexual health, research has not examined reliability of information provided by gay, lesbian, and bisexual (GLB) youths. Test-retest reliability of self-reported sexual behaviors, sexual orientation, sexual identity, and psychosexual developmental milestones was examined among an ethnically diverse sample of 64 self-identified GLB youths. Two face-to-face interviews were conducted approximately two weeks apart using the Sexual Risk Behavior Assessment Schedule for Homosexual Youths (SERBAS-Y-HM). Overall, the mean of the test-retest reliability coefficients was substantial for 6 of the 7 domains: lifetime sexual behaviors (M = .89), sexual behavior in the past 3 months (M = .96), unprotected sexual behavior in the past 3 months (M = .93), sexual identity (κ = .89), sexual orientation (M = .82), and ages of various psychosexual developmental milestones (M = .77). Inconsistent reliability was found for reports of sexual behaviors while using substances. A small number of gender differences emerged, with lower reliability among female youths in the lifetime number of same-sex partners. The overall findings suggest that a wide range of self-reported sexual information can be reliably assessed among GLB youths by means of interviewer-administered questionnaires, such as the SERBAS-Y-HM. PMID:16752124
Role of information systems in public health services.
Hartshorne, J E; Carstens, I L
1990-07-01
The purpose of this review is to establish a conceptual framework on the role of information systems in public health care. Information is indispensable for effective management and development of health services and therefore considered as an important operational asset or resource. A Health Information System is mainly required to support management and operations at four levels: namely transactional and functional; operational control; management planning and control; and strategic planning. To provide the necessary information needs of users at these levels of management in the health care system, a structured information system coupled with appropriate information technology is required. Adequate and relevant information is needed regarding population characteristics, resources available and expended, output and outcome of health care activities. Additionally information needs to be reliable, accurate, timely, easily accessible and presented in a compact and meaningful form. With a well-planned health information system health authorities would be in a position to provide a quality, cost-effective and efficient health service for as many people as need it, optimal utilisation of resources and to maintain and improve the community's health status.
Quantification of Uncertainty in Full-Waveform Moment Tensor Inversion for Regional Seismicity
NASA Astrophysics Data System (ADS)
Jian, P.; Hung, S.; Tseng, T.
2013-12-01
Routinely and instantaneously determined moment tensor solutions deliver basic information for investigating faulting nature of earthquakes and regional tectonic structure. The accuracy of full-waveform moment tensor inversion mostly relies on azimuthal coverage of stations, data quality and previously known earth's structure (i.e., impulse responses or Green's functions). However, intrinsically imperfect station distribution, noise-contaminated waveform records and uncertain earth structure can often result in large deviations of the retrieved source parameters from the true ones, which prohibits the use of routinely reported earthquake catalogs for further structural and tectonic interferences. Duputel et al. (2012) first systematically addressed the significance of statistical uncertainty estimation in earthquake source inversion and exemplified that the data covariance matrix, if prescribed properly to account for data dependence and uncertainty due to incomplete and erroneous data and hypocenter mislocation, cannot only be mapped onto the uncertainty estimate of resulting source parameters, but it also aids obtaining more stable and reliable results. Over the past decade, BATS (Broadband Array in Taiwan for Seismology) has steadily devoted to building up a database of good-quality centroid moment tensor (CMT) solutions for moderate to large magnitude earthquakes that occurred in Taiwan area. Because of the lack of the uncertainty quantification and reliability analysis, it remains controversial to use the reported CMT catalog directly for further investigation of regional tectonics, near-source strong ground motions, and seismic hazard assessment. In this study, we develop a statistical procedure to make quantitative and reliable estimates of uncertainty in regional full-waveform CMT inversion. The linearized inversion scheme adapting efficient estimation of the covariance matrices associated with oversampled noisy waveform data and errors of biased centroid positions is implemented and inspected for improving source parameter determination of regional seismicity in Taiwan. Synthetic inversion tests demonstrate the resolved moment tensors would better match the hypothetical CMT solutions, and tend to suppress unreal non-double-couple components and reduce the trade-off between focal mechanism and centroid depth if individual signal-to-noise ratios and correlation lengths for 3-component seismograms at each station and mislocation uncertainties are properly taken into account. We further testify the capability of our scheme in retrieving the robust CMT information for mid-sized (Mw~3.5) and offshore earthquakes in Taiwan, which offers immediate and broad applications in detailed modelling of regional stress field and deformation pattern and mapping of subsurface velocity structures.
A Protocol for Advanced Psychometric Assessment of Surveys
Squires, Janet E.; Hayduk, Leslie; Hutchinson, Alison M.; Cranley, Lisa A.; Gierl, Mark; Cummings, Greta G.; Norton, Peter G.; Estabrooks, Carole A.
2013-01-01
Background and Purpose. In this paper, we present a protocol for advanced psychometric assessments of surveys based on the Standards for Educational and Psychological Testing. We use the Alberta Context Tool (ACT) as an exemplar survey to which this protocol can be applied. Methods. Data mapping, acceptability, reliability, and validity are addressed. Acceptability is assessed with missing data frequencies and the time required to complete the survey. Reliability is assessed with internal consistency coefficients and information functions. A unitary approach to validity consisting of accumulating evidence based on instrument content, response processes, internal structure, and relations to other variables is taken. We also address assessing performance of survey data when aggregated to higher levels (e.g., nursing unit). Discussion. In this paper we present a protocol for advanced psychometric assessment of survey data using the Alberta Context Tool (ACT) as an exemplar survey; application of the protocol to the ACT survey is underway. Psychometric assessment of any survey is essential to obtaining reliable and valid research findings. This protocol can be adapted for use with any nursing survey. PMID:23401759
Probabilistic simulation of uncertainties in thermal structures
NASA Technical Reports Server (NTRS)
Chamis, Christos C.; Shiao, Michael
1990-01-01
Development of probabilistic structural analysis methods for hot structures is a major activity at Lewis Research Center. It consists of five program elements: (1) probabilistic loads; (2) probabilistic finite element analysis; (3) probabilistic material behavior; (4) assessment of reliability and risk; and (5) probabilistic structural performance evaluation. Recent progress includes: (1) quantification of the effects of uncertainties for several variables on high pressure fuel turbopump (HPFT) blade temperature, pressure, and torque of the Space Shuttle Main Engine (SSME); (2) the evaluation of the cumulative distribution function for various structural response variables based on assumed uncertainties in primitive structural variables; (3) evaluation of the failure probability; (4) reliability and risk-cost assessment, and (5) an outline of an emerging approach for eventual hot structures certification. Collectively, the results demonstrate that the structural durability/reliability of hot structural components can be effectively evaluated in a formal probabilistic framework. In addition, the approach can be readily extended to computationally simulate certification of hot structures for aerospace environments.
Smith, David; Harvey, Peter; Lawn, Sharon; Harris, Melanie; Battersby, Malcolm
2017-01-01
To evaluate the factor structure of the revised Partners in Health (PIH) scale for measuring chronic condition self-management in a representative sample from the Australian community. A series of consultations between clinical groups underpinned the revision of the PIH. The factors in the revised instrument were proposed to be: knowledge of illness and treatment, patient-health professional partnership, recognition and management of symptoms and coping with chronic illness. Participants (N = 904) reporting having a chronic illness completed the revised 12-item scale. Two a priori models, the 4-factor and bi-factor models were then evaluated using Bayesian confirmatory factor analysis (BCFA). Final model selection was established on model complexity, posterior predictive p values and deviance information criterion. Both 4-factor and bi-factor BCFA models with small informative priors for cross-loadings provided an acceptable fit with the data. The 4-factor model was shown to provide a better and more parsimonious fit with the observed data in terms of substantive theory. McDonald's omega coefficients indicated that the reliability of subscale raw scores was mostly in the acceptable range. The findings showed that the PIH scale is a relevant and structurally valid instrument for measuring chronic condition self-management in an Australian community. The PIH scale may help health professionals to introduce the concept of self-management to their patients and provide assessment of areas of self-management. A limitation is the narrow range of validated PIH measurement properties to date. Further research is needed to evaluate other important properties such as test-retest reliability, responsiveness over time and content validity.
Kaufmann, A; Walker, S; Mol, G
2016-04-15
Elucidation of the elemental compositions of unknown compounds (e.g., in metabolomics) generally relies on the availability of accurate masses and isotopic ratios. This study focuses on the information provided by the abundance ratio within a product ion pair (monoisotopic versus the first isotopic peak) when isolating and fragmenting the first isotopic ion (first isotopic mass spectrum) of the precursor. This process relies on the capability of the quadrupole within the Q Orbitrap instrument to isolate a very narrow mass window. Selecting only the first isotopic peak (first isotopic mass spectrum) leads to the observation of a unique product ion pair. The lighter ion within such an isotopologue pair is monoisotopic, while the heavier ion contains a single carbon isotope. The observed abundance ratio is governed by the percentage of carbon atoms lost during the fragmentation and can be described by a hypergeometric distribution. The observed carbon isotopologue abundance ratio (product ion isotopologue pattern) gives reliable information regarding the percentage of carbon atoms lost in the fragmentation process. It therefore facilitates the elucidation of the involved precursor and product ions. Unlike conventional isotopic abundances, the product ion isotopologue pattern is hardly affected by isobaric interferences. Furthermore, the appearance of these pairs greatly aids in cleaning up a 'matrix-contaminated' product ion spectrum. The product ion isotopologue pattern is a valuable tool for structural elucidation. It increases confidence in results and permits structural elucidations for heavier ions. This tool is also very useful in elucidating the elemental composition of product ions. Such information is highly valued in the field of multi-residue analysis, where the accurate mass of product ions is required for the confirmation process. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
78 FR 22773 - Revisions to Reliability Standard for Transmission Vegetation Management; Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-17
...; Order No. 777] Revisions to Reliability Standard for Transmission Vegetation Management; Correction... other requirements the North American Electric Reliability Corporation (NERC) needs to submit when modifying certain Reliability Standards. DATES: Effective on May 28, 2013. FOR FURTHER INFORMATION CONTACT...
75 FR 71678 - Commission Information Collection Activities; Comment Request; Extension
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-24
... Maintenance Reliability Standards'' (OMB Control No. 1902-0247), is required to implement the statutory... Electric Reliability Organization (ERO) to develop mandatory and enforceable reliability standards, which are subject to Commission review and approval. Once approved, the reliability standards may be...
Test-bed for the remote health monitoring system for bridge structures using FBG sensors
NASA Astrophysics Data System (ADS)
Lee, Chin-Hyung; Park, Ki-Tae; Joo, Bong-Chul; Hwang, Yoon-Koog
2009-05-01
This paper reports on test-bed for the long-term health monitoring system for bridge structures employing fiber Bragg grating (FBG) sensors, which is remotely accessible via the web, to provide real-time quantitative information on a bridge's response to live loading and environmental changes, and fast prediction of the structure's integrity. The sensors are attached on several locations of the structure and connected to a data acquisition system permanently installed onsite. The system can be accessed through remote communication using an optical cable network, through which the evaluation of the bridge behavior under live loading can be allowed at place far away from the field. Live structural data are transmitted continuously to the server computer at the central office. The server computer is connected securely to the internet, where data can be retrieved, processed and stored for the remote web-based health monitoring. Test-bed revealed that the remote health monitoring technology will enable practical, cost-effective, and reliable condition assessment and maintenance of bridge structures.
Murphy, Dennis D; Weiland, Paul S
2011-02-01
The Endangered Species Act is intended to conserve at-risk species and the ecosystems upon which they depend, and it is premised on the notion that if the wildlife agencies that are charged with implementing the statute use the best available scientific information, they can successfully carry out this intention. We assess effects analysis as a tool for using best science to guide agency decisions under the Act. After introducing effects analysis, we propose a framework that facilitates identification and use of the best available information in the development of agency determinations. The framework includes three essential steps--the collection of reliable scientific information, the critical assessment and synthesis of available data and analyses derived from those data, and the analysis of the effects of actions on listed species and their habitats. We warn of likely obstacles to rigorous, structured effect analyses and describe the extent to which independent scientific review may assist in overcoming these obstacles. We conclude by describing eight essential elements that are required for a successful effects analysis.
An automated procedure for detection of IDP's dwellings using VHR satellite imagery
NASA Astrophysics Data System (ADS)
Jenerowicz, Malgorzata; Kemper, Thomas; Soille, Pierre
2011-11-01
This paper presents the results for the estimation of dwellings structures in Al Salam IDP Camp, Southern Darfur, based on Very High Resolution multispectral satellite images obtained by implementation of Mathematical Morphology analysis. A series of image processing procedures, feature extraction methods and textural analysis have been applied in order to provide reliable information about dwellings structures. One of the issues in this context is related to similarity of the spectral response of thatched dwellings' roofs and the surroundings in the IDP camps, where the exploitation of multispectral information is crucial. This study shows the advantage of automatic extraction approach and highlights the importance of detailed spatial and spectral information analysis based on multi-temporal dataset. The additional data fusion of high-resolution panchromatic band with lower resolution multispectral bands of WorldView-2 satellite has positive influence on results and thereby can be useful for humanitarian aid agency, providing support of decisions and estimations of population especially in situations when frequent revisits by space imaging system are the only possibility of continued monitoring.
An adaptive deep-coupled GNSS/INS navigation system with hybrid pre-filter processing
NASA Astrophysics Data System (ADS)
Wu, Mouyan; Ding, Jicheng; Zhao, Lin; Kang, Yingyao; Luo, Zhibin
2018-02-01
The deep-coupling of a global navigation satellite system (GNSS) with an inertial navigation system (INS) can provide accurate and reliable navigation information. There are several kinds of deeply-coupled structures. These can be divided mainly into coherent and non-coherent pre-filter based structures, which have their own strong advantages and disadvantages, especially in accuracy and robustness. In this paper, the existing pre-filters of the deeply-coupled structures are analyzed and modified to improve them firstly. Then, an adaptive GNSS/INS deeply-coupled algorithm with hybrid pre-filters processing is proposed to combine the advantages of coherent and non-coherent structures. An adaptive hysteresis controller is designed to implement the hybrid pre-filters processing strategy. The simulation and vehicle test results show that the adaptive deeply-coupled algorithm with hybrid pre-filters processing can effectively improve navigation accuracy and robustness, especially in a GNSS-challenged environment.
NASA Astrophysics Data System (ADS)
Davis, L. J.; Boggess, M.; Kodpuak, E.; Deutsch, M.
2012-11-01
We report on a model for the deposition of three dimensional, aggregated nanocrystalline silver films, and an efficient numerical simulation method developed for visualizing such structures. We compare our results to a model system comprising chemically deposited silver films with morphologies ranging from dilute, uniform distributions of nanoparticles to highly porous aggregated networks. Disordered silver films grown in solution on silica substrates are characterized using digital image analysis of high resolution scanning electron micrographs. While the latter technique provides little volume information, plane-projected (two dimensional) island structure and surface coverage may be reliably determined. Three parameters governing film growth are evaluated using these data and used as inputs for the deposition model, greatly reducing computing requirements while still providing direct access to the complete (bulk) structure of the films throughout the growth process. We also show how valuable three dimensional characteristics of the deposited materials can be extracted using the simulated structures.
[The computer assisted pacemaker clinic at the regional hospital of Udine (author's transl)].
Feruglio, G A; Lestuzzi, L; Carminati, D
1978-01-01
For a close follow-up of large groups of pacemaker patients and for evaluation of long term pacing on a reliable statistical basis, many pacemaker centers in the world are now using computer systems. A patient data system with structured display records, designed to give complete, comprehensive and surveyable information and which are immediately retrievable 24 hours a day, on display or printed sets, seems to offer an ideal solution. The pacemaker clinic at the Regional Hospital of Udine has adopted this type of system. The clinic in linked to a live, on-line patient data system (G/3, Informatica Friuli-Venezia Giulia). The input and retrieval of information are made through a conventional keyboard. The input formats have fixed headings with coded alternatives and a limited space for comments in free text. The computer edits the coded information to surveyable reviews. Searches can be made on coded information and data of interest.
Information Technology in Complex Health Services
Southon, Frank Charles Gray; Sauer, Chris; Dampney, Christopher Noel Grant (Kit)
1997-01-01
Abstract Objective: To identify impediments to the successful transfer and implementation of packaged information systems through large, divisionalized health services. Design: A case analysis of the failure of an implementation of a critical application in the Public Health System of the State of New South Wales, Australia, was carried out. This application had been proven in the United States environment. Measurements: Interviews involving over 60 staff at all levels of the service were undertaken by a team of three. The interviews were recorded and analyzed for key themes, and the results were shared and compared to enable a continuing critical assessment. Results: Two components of the transfer of the system were considered: the transfer from a different environment, and the diffusion throughout a large, divisionalized organization. The analyses were based on the Scott-Morton organizational fit framework. In relation to the first, it was found that there was a lack of fit in the business environments and strategies, organizational structures and strategy-structure pairing as well as the management process-roles pairing. The diffusion process experienced problems because of the lack of fit in the strategy-structure, strategy-structure-management processes, and strategy-structure-role relationships. Conclusion: The large-scale developments of integrated health services present great challenges to the efficient and reliable implementation of information technology, especially in large, divisionalized organizations. There is a need to take a more sophisticated approach to understanding the complexities of organizational factors than has traditionally been the case. PMID:9067877
Southon, F C; Sauer, C; Grant, C N
1997-01-01
To identify impediments to the successful transfer and implementation of packaged information systems through large, divisionalized health services. A case analysis of the failure of an implementation of a critical application in the Public Health System of the State of New South Wales, Australia, was carried out. This application had been proven in the United States environment. Interviews involving over 60 staff at all levels of the service were undertaken by a team of three. The interviews were recorded and analyzed for key themes, and the results were shared and compared to enable a continuing critical assessment. Two components of the transfer of the system were considered: the transfer from a different environment, and the diffusion throughout a large, divisionalized organization. The analyses were based on the Scott-Morton organizational fit framework. In relation to the first, it was found that there was a lack of fit in the business environments and strategies, organizational structures and strategy-structure pairing as well as the management process-roles pairing. The diffusion process experienced problems because of the lack of fit in the strategy-structure, strategy-structure-management processes, and strategy-structure-role relationships. The large-scale developments of integrated health services present great challenges to the efficient and reliable implementation of information technology, especially in large, divisionalized organizations. There is a need to take a more sophisticated approach to understanding the complexities of organizational factors than has traditionally been the case.
Friedman, Carol; Hripcsak, George; Shagina, Lyuda; Liu, Hongfang
1999-01-01
Objective: To design a document model that provides reliable and efficient access to clinical information in patient reports for a broad range of clinical applications, and to implement an automated method using natural language processing that maps textual reports to a form consistent with the model. Methods: A document model that encodes structured clinical information in patient reports while retaining the original contents was designed using the extensible markup language (XML), and a document type definition (DTD) was created. An existing natural language processor (NLP) was modified to generate output consistent with the model. Two hundred reports were processed using the modified NLP system, and the XML output that was generated was validated using an XML validating parser. Results: The modified NLP system successfully processed all 200 reports. The output of one report was invalid, and 199 reports were valid XML forms consistent with the DTD. Conclusions: Natural language processing can be used to automatically create an enriched document that contains a structured component whose elements are linked to portions of the original textual report. This integrated document model provides a representation where documents containing specific information can be accurately and efficiently retrieved by querying the structured components. If manual review of the documents is desired, the salient information in the original reports can also be identified and highlighted. Using an XML model of tagging provides an additional benefit in that software tools that manipulate XML documents are readily available. PMID:9925230
Evaluation methodologies for an advanced information processing system
NASA Technical Reports Server (NTRS)
Schabowsky, R. S., Jr.; Gai, E.; Walker, B. K.; Lala, J. H.; Motyka, P.
1984-01-01
The system concept and requirements for an Advanced Information Processing System (AIPS) are briefly described, but the emphasis of this paper is on the evaluation methodologies being developed and utilized in the AIPS program. The evaluation tasks include hardware reliability, maintainability and availability, software reliability, performance, and performability. Hardware RMA and software reliability are addressed with Markov modeling techniques. The performance analysis for AIPS is based on queueing theory. Performability is a measure of merit which combines system reliability and performance measures. The probability laws of the performance measures are obtained from the Markov reliability models. Scalar functions of this law such as the mean and variance provide measures of merit in the AIPS performability evaluations.
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.
Luebbe, Aaron M; Mancini, Kathryn J; Kiel, Elizabeth J; Spangler, Brooke R; Semlak, Julie L; Fussner, Lauren M
2016-08-24
The current study tests the underlying structure of a multidimensional construct of helicopter parenting (HP), assesses reliability of the construct, replicates past relations of HP to poor emotional functioning, and expands the literature to investigate links of HP to emerging adults' decision-making and academic functioning. A sample of 377 emerging adults (66% female; ages 17-30; 88% European American) were administered several items assessing HP as well as measures of other parenting behaviors, depression, anxiety, decision-making style, grade point average, and academic functioning. Exploratory factor analysis results suggested a four-factor, 23-item measure that encompassed varying levels of parental involvement in the personal and professional lives of their children. A bifactor model was also fit to the data and suggested the presence of a reliable overarching HP factor in addition to three reliable subfactors. The fourth subfactor was not reliable and item variances were subsumed by the general HP factor. HP was found to be distinct from, but correlated in expected ways with, other reports of parenting behavior. HP was also associated with poorer functioning in emotional functioning, decision making, and academic functioning. Parents' information-seeking behaviors, when done in absences of other HP behaviors, were associated with better decision making and academic functioning. © The Author(s) 2016.
How to: identify non-tuberculous Mycobacterium species using MALDI-TOF mass spectrometry.
Alcaide, F; Amlerová, J; Bou, G; Ceyssens, P J; Coll, P; Corcoran, D; Fangous, M-S; González-Álvarez, I; Gorton, R; Greub, G; Hery-Arnaud, G; Hrábak, J; Ingebretsen, A; Lucey, B; Marekoviċ, I; Mediavilla-Gradolph, C; Monté, M R; O'Connor, J; O'Mahony, J; Opota, O; O'Reilly, B; Orth-Höller, D; Oviaño, M; Palacios, J J; Palop, B; Pranada, A B; Quiroga, L; Rodríguez-Temporal, D; Ruiz-Serrano, M J; Tudó, G; Van den Bossche, A; van Ingen, J; Rodriguez-Sanchez, B
2018-06-01
The implementation of MALDI-TOF MS for microorganism identification has changed the routine of the microbiology laboratories as we knew it. Most microorganisms can now be reliably identified within minutes using this inexpensive, user-friendly methodology. However, its application in the identification of mycobacteria isolates has been hampered by the structure of their cell wall. Improvements in the sample processing method and in the available database have proved key factors for the rapid and reliable identification of non-tuberculous mycobacteria isolates using MALDI-TOF MS. The main objective is to provide information about the proceedings for the identification of non-tuberculous isolates using MALDI-TOF MS and to review different sample processing methods, available databases, and the interpretation of the results. Results from relevant studies on the use of the available MALDI-TOF MS instruments, the implementation of innovative sample processing methods, or the implementation of improved databases are discussed. Insight about the methodology required for reliable identification of non-tuberculous mycobacteria and its implementation in the microbiology laboratory routine is provided. Microbiology laboratories where MALDI-TOF MS is available can benefit from its capacity to identify most clinically interesting non-tuberculous mycobacteria in a rapid, reliable, and inexpensive manner. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Information sources used by parents to learn about medications they are giving their children.
Holappa, Miina; Ahonen, Riitta; Vainio, Kirsti; Hämeen-Anttila, Katri
2012-01-01
Previous studies have indicated the use of medication by children to be dependent on the attitudes of knowledge of their parents; however, little is known about sources parents might use in driving medication use decisions. The aim of this study was to describe the information sources that parents use regarding their children's medication and their perceptions of the reliability of these information sources. This study is part of a cross-sectional population survey with a random sample of 6000 children younger than 12 years. The response rate of the questionnaire was 67%. Parents were asked about the use of information sources and their perception of reliability with a list of 16 information sources. The information sources that parents reported having used were physicians (72%), patient information leaflets (PILs) (67%), public or school health nurses (52%), and pharmacists (44%). Regardless of the child's age, physicians were the parents' most-used information source. Physicians were the most-used information source also when the child had at least 1 of the 4 most common long-term diseases among children in Finland (asthma, diabetes, epilepsy, and juvenile idiopathic arthritis). Parents considered physicians (50%), PILs (31%), pharmacists (27%), nurses (20%), and public or school health nurses (17%) very reliable information sources. Finnish parents seek information from health care professionals and PILs when looking for information concerning their children's medication. Furthermore, they find health care professionals and PILs to be reliable information sources. Copyright © 2012 Elsevier Inc. All rights reserved.
Perceptions of Health-Related Information on Facebook: Cross-Sectional Study Among Vietnamese Youths
Zhang, Melvyn WB; Le, Huong Thi; Nguyen, Hinh Duc; Tran, Tho Dinh; Latkin, Carl A; Ho, Roger CM
2017-01-01
Background While health information websites may have previously been the core source of information about health-related conditions on the Internet, social networking sites are increasingly replacing those websites as a source of health-related information. The increasingly popularity of social networking sites among the general population has consequential impact on health policies as well as health-related interventions. To date, there remains a paucity of research conducted in developing countries like Vietnam looking at the influence of social networking sites. Objective Our goal is to establish the baseline use of Facebook among Vietnamese youths and establish their perception of the reliability and usefulness of health-related information that they previously encountered while using the social networking site. Methods An online cross-sectional study was conducted from August 2015 to October 2015. Respondent-driven sampling (RDS) technique was used in the recruitment of participants. Sociodemographic, health status, behaviors, Facebook use and belief of information on Facebook, and interpersonal influence of social network sites were collected via an online structured questionnaire. Results Among 1080 participants, 72.87% (787/1080) reported being interested in health information on Facebook, and 50.74% (548/1080) and 17.50% (189/1080) perceived the information to be reliable and useful, respectively. A total of 10.93% (118/1080) of the participants also reported that they would follow the health advice they obtained from Facebook. Of significance, 7.13% (77/1080) of the participants also reported peer influences on their behavior. Factors that mediate Vietnamese perceptions of the information online include gender, level of perceived stress, age, educational level, and interpersonal influences from Facebook. Conclusions Our study is perhaps one of the first conducted in Vietnam that looks at the relationship between health information on Facebook and factors that might influence young Vietnamese perceptions of the information and the consequential use of that information. PMID:28882813
Robotic Assembly of Truss Structures for Space Systems and Future Research Plans
NASA Technical Reports Server (NTRS)
Doggett, William
2002-01-01
Many initiatives under study by both the space science and earth science communities require large space systems, i.e. with apertures greater than 15 m or dimensions greater than 20 m. This paper reviews the effort in NASA Langley Research Center's Automated Structural Assembly Laboratory which laid the foundations for robotic construction of these systems. In the Automated Structural Assembly Laboratory reliable autonomous assembly and disassembly of an 8 meter planar structure composed of 102 truss elements covered by 12 panels was demonstrated. The paper reviews the hardware and software design philosophy which led to reliable operation during weeks of near continuous testing. Special attention is given to highlight the features enhancing assembly reliability.
NASA Astrophysics Data System (ADS)
Hanish Nithin, Anu; Omenzetter, Piotr
2017-04-01
Optimization of the life-cycle costs and reliability of offshore wind turbines (OWTs) is an area of immense interest due to the widespread increase in wind power generation across the world. Most of the existing studies have used structural reliability and the Bayesian pre-posterior analysis for optimization. This paper proposes an extension to the previous approaches in a framework for probabilistic optimization of the total life-cycle costs and reliability of OWTs by combining the elements of structural reliability/risk analysis (SRA), the Bayesian pre-posterior analysis with optimization through a genetic algorithm (GA). The SRA techniques are adopted to compute the probabilities of damage occurrence and failure associated with the deterioration model. The probabilities are used in the decision tree and are updated using the Bayesian analysis. The output of this framework would determine the optimal structural health monitoring and maintenance schedules to be implemented during the life span of OWTs while maintaining a trade-off between the life-cycle costs and risk of the structural failure. Numerical illustrations with a generic deterioration model for one monitoring exercise in the life cycle of a system are demonstrated. Two case scenarios, namely to build initially an expensive and robust or a cheaper but more quickly deteriorating structures and to adopt expensive monitoring system, are presented to aid in the decision-making process.
Bayesian Inference for NASA Probabilistic Risk and Reliability Analysis
NASA Technical Reports Server (NTRS)
Dezfuli, Homayoon; Kelly, Dana; Smith, Curtis; Vedros, Kurt; Galyean, William
2009-01-01
This document, Bayesian Inference for NASA Probabilistic Risk and Reliability Analysis, is intended to provide guidelines for the collection and evaluation of risk and reliability-related data. It is aimed at scientists and engineers familiar with risk and reliability methods and provides a hands-on approach to the investigation and application of a variety of risk and reliability data assessment methods, tools, and techniques. This document provides both: A broad perspective on data analysis collection and evaluation issues. A narrow focus on the methods to implement a comprehensive information repository. The topics addressed herein cover the fundamentals of how data and information are to be used in risk and reliability analysis models and their potential role in decision making. Understanding these topics is essential to attaining a risk informed decision making environment that is being sought by NASA requirements and procedures such as 8000.4 (Agency Risk Management Procedural Requirements), NPR 8705.05 (Probabilistic Risk Assessment Procedures for NASA Programs and Projects), and the System Safety requirements of NPR 8715.3 (NASA General Safety Program Requirements).
An autonomous structural health monitoring solution
NASA Astrophysics Data System (ADS)
Featherston, Carol A.; Holford, Karen M.; Pullin, Rhys; Lees, Jonathan; Eaton, Mark; Pearson, Matthew
2013-05-01
Combining advanced sensor technologies, with optimised data acquisition and diagnostic and prognostic capability, structural health monitoring (SHM) systems provide real-time assessment of the integrity of bridges, buildings, aircraft, wind turbines, oil pipelines and ships, leading to improved safety and reliability and reduced inspection and maintenance costs. The implementation of power harvesting, using energy scavenged from ambient sources such as thermal gradients and sources of vibration in conjunction with wireless transmission enables truly autonomous systems, reducing the need for batteries and associated maintenance in often inaccessible locations, alongside bulky and expensive wiring looms. The design and implementation of such a system however presents numerous challenges. A suitable energy source or multiple sources capable of meeting the power requirements of the system, over the entire monitoring period, in a location close to the sensor must be identified. Efficient power management techniques must be used to condition the power and deliver it, as required, to enable appropriate measurements to be taken. Energy storage may be necessary, to match a continuously changing supply and demand for a range of different monitoring states including sleep, record and transmit. An appropriate monitoring technique, capable of detecting, locating and characterising damage and delivering reliable information, whilst minimising power consumption, must be selected. Finally a wireless protocol capable of transmitting the levels of information generated at the rate needed in the required operating environment must be chosen. This paper considers solutions to some of these challenges, and in particular examines SHM in the context of the aircraft environment.
Social network models predict movement and connectivity in ecological landscapes
Fletcher, R.J.; Acevedo, M.A.; Reichert, Brian E.; Pias, Kyle E.; Kitchens, W.M.
2011-01-01
Network analysis is on the rise across scientific disciplines because of its ability to reveal complex, and often emergent, patterns and dynamics. Nonetheless, a growing concern in network analysis is the use of limited data for constructing networks. This concern is strikingly relevant to ecology and conservation biology, where network analysis is used to infer connectivity across landscapes. In this context, movement among patches is the crucial parameter for interpreting connectivity but because of the difficulty of collecting reliable movement data, most network analysis proceeds with only indirect information on movement across landscapes rather than using observed movement to construct networks. Statistical models developed for social networks provide promising alternatives for landscape network construction because they can leverage limited movement information to predict linkages. Using two mark-recapture datasets on individual movement and connectivity across landscapes, we test whether commonly used network constructions for interpreting connectivity can predict actual linkages and network structure, and we contrast these approaches to social network models. We find that currently applied network constructions for assessing connectivity consistently, and substantially, overpredict actual connectivity, resulting in considerable overestimation of metapopulation lifetime. Furthermore, social network models provide accurate predictions of network structure, and can do so with remarkably limited data on movement. Social network models offer a flexible and powerful way for not only understanding the factors influencing connectivity but also for providing more reliable estimates of connectivity and metapopulation persistence in the face of limited data.
Diviani, Nicola; Dima, Alexandra Lelia; Schulz, Peter Johannes
2017-04-11
The eHealth Literacy Scale (eHEALS) is a tool to assess consumers' comfort and skills in using information technologies for health. Although evidence exists of reliability and construct validity of the scale, less agreement exists on structural validity. The aim of this study was to validate the Italian version of the eHealth Literacy Scale (I-eHEALS) in a community sample with a focus on its structural validity, by applying psychometric techniques that account for item difficulty. Two Web-based surveys were conducted among a total of 296 people living in the Italian-speaking region of Switzerland (Ticino). After examining the latent variables underlying the observed variables of the Italian scale via principal component analysis (PCA), fit indices for two alternative models were calculated using confirmatory factor analysis (CFA). The scale structure was examined via parametric and nonparametric item response theory (IRT) analyses accounting for differences between items regarding the proportion of answers indicating high ability. Convergent validity was assessed by correlations with theoretically related constructs. CFA showed a suboptimal model fit for both models. IRT analyses confirmed all items measure a single dimension as intended. Reliability and construct validity of the final scale were also confirmed. The contrasting results of factor analysis (FA) and IRT analyses highlight the importance of considering differences in item difficulty when examining health literacy scales. The findings support the reliability and validity of the translated scale and its use for assessing Italian-speaking consumers' eHealth literacy. ©Nicola Diviani, Alexandra Lelia Dima, Peter Johannes Schulz. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 11.04.2017.
Skritskaya, Natalia A; Mauro, Christine; Olonoff, Matthew; Qiu, Xin; Duncan, Sarah; Wang, Yuanjia; Duan, Naihua; Lebowitz, Barry; Reynolds, Charles F; Simon, Naomi M; Zisook, Sidney; Shear, M Katherine
2017-05-01
Maladaptive cognitions related to loss are thought to contribute to development of complicated grief and are crucial to address in treatment, but tools available to assess them are limited. This paper introduces the Typical Beliefs Questionnaire (TBQ), a 25-item self-report instrument to assess cognitions that interfere with adaptation to loss. Study participants completed an assessment battery during their initial evaluation and again after completing treatment at 20 weeks. Test-retest reliability was assessed on a subsample of the participants who did not show change in complicated grief severity after the first 4 weeks of treatment. To examine latent structure of the TBQ, an exploratory factor analysis (EFA) was performed. Academic medical centers in Boston, New York, Pittsburgh, and San Diego from 2010-2014. 394 bereaved adults who met criteria for complicated grief. The TBQ along with assessments of complicated grief symptoms and related avoidance, depression symptoms, functional impairment, and perceived social support. The TBQ exhibited good internal consistency (α = 0.82) and test-retest reliability (N = 105; intraclass correlation coefficient = 0.74). EFA indicated a five-factor structure: "Protesting the Death," "Negative Thoughts About the World," "Needing the Person," "Less Grief is Wrong" and "Grieving Too Much." The total score and all factors showed sensitivity to change with treatment. This new tool allows a clinician to quickly and reliably ascertain presence of specific maladaptive cognitions related to complicated grief, and subsequently, to use the information to aid a diagnostic assessment, to structure the treatment, and to measure treatment outcomes. Copyright © 2016 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.
Ding, Ding; Hofstetter, C Richard; Norman, Gregory J; Irvin, Veronica L; Chhay, Douglas; Hovell, Melbourne F
2011-02-01
Immigration involves challenges and distress, which affect health and well-being of immigrants. Koreans are a recent, fast-growing, but understudied group of immigrants in the USA, and no study has established or evaluated any immigration stress measure among this population. This study explores psychometric properties of Korean-translated Demands of Immigration (DI) Scale among first-generation female Korean immigrants in California. Analyses included evaluation of factor structure, reliability, validity, and descriptive statistics of subscales. A surname-driven sampling strategy was applied to randomly select a representative sample of adult female Korean immigrants in California. Telephone interviews were conducted by trained bilingual interviewers. Study sample included 555 first-generation female Korean immigrants who were interviewed in Korean language. The 22-item DI Scale was used to assess immigration stress in the study sample. Exploratory factor analysis suggested six correlated factors in the DI Scale: language barriers; sense of loss; not feeling at home; perceived discrimination; novelty; and occupation. Confirmatory factor analysis validated the factor structure. Language barriers accounted for the most variance of the DI Scale (29.11%). The DI Scale demonstrated good internal consistency reliability and construct validity. Evidence has been offered that the Korean-translated DI Scale is a reliable and valid measurement tool to examine immigration stress among Korean immigrants. The Korean-translated DI Scale has replicated factor structure obtained in other ethnicities, but addition of cultural-specific items is suggested for Korean immigrants. High levels of language and occupation-related stress warrant attention from researchers, social workers, and policy-makers. Findings from this study will inform future interventions to alleviate stress due to demands of immigration.
SHM reliability and implementation - A personal military aviation perspective
NASA Astrophysics Data System (ADS)
Lindgren, Eric A.
2016-02-01
Structural Health Monitoring has been proposed as a solution to address the needs of military aviation to reduce the time and cost to perform nondestructive inspections. While the potential to realize significant benefits exist, there are considerations that have to be addressed before such systems can be integrated into military platforms. Some considerations are pervasive to all aviation, such as how to assess the reliability and reproducible capability of these systems. However, there are other challenges unique to military aviation that must be overcome before these types of systems can be used. This presentation and paper are intended as a complement to the review of the outcome of the SAE G-11 SHM committee special workshop on SHM reliability in April of 2015. It will address challenges unique to military aviation that stem from different approaches to managing structural integrity (i.e. safety), frequency of use, design differences, various maintenance practices, and additional descriptions addressing differences in the execution of inspections. The objective of this presentation is to improve the awareness of the research and development community to the different and unique requirements found in military aviation, including the differences between countries, services, and aircraft type. This information should assist the research and development community in identifying and attacking key challenges. It is not intended to be comprehensive overview of all stakeholders' perspectives, but to serve as a launch point for additional discussion and exploration of opportunities to realize the potential of Structural Health Monitoring to assist in the management of military aviation assets. The views expressed in this publication are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government.
Optimization of structures on the basis of fracture mechanics and reliability criteria
NASA Technical Reports Server (NTRS)
Heer, E.; Yang, J. N.
1973-01-01
Systematic summary of factors which are involved in optimization of given structural configuration is part of report resulting from study of analysis of objective function. Predicted reliability of performance of finished structure is sharply dependent upon results of coupon tests. Optimization analysis developed by study also involves expected cost of proof testing.
Reliability, Validity, and Factor Structure of the Imaginative Capability Scale
ERIC Educational Resources Information Center
Liang, Chaoyun; Chia, Tsorng-Lin
2014-01-01
Three studies were combined to test the reliability, validity, and factor structure of the imaginative capability scale (ICS). The ICS was a new self-report measure, which was developed to be empirically valid and easy to administer. Study 1 consisted in an exploratory factor analysis to determine the most appropriate structure of the ICS in a…
76 FR 65504 - Proposed Agency Information Collection
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-21
..., including the validity of the methodology and assumptions used; (c) ways to enhance the quality, utility... Reliability Standard, FAC- 008-3--Facility Ratings, developed by the North American Electric Reliability... Reliability Standard FAC- 008-3 is pending before the Commission. The proposed Reliability Standard modifies...
ASSESSING AND COMBINING RELIABILITY OF PROTEIN INTERACTION SOURCES
LEACH, SONIA; GABOW, AARON; HUNTER, LAWRENCE; GOLDBERG, DEBRA S.
2008-01-01
Integrating diverse sources of interaction information to create protein networks requires strategies sensitive to differences in accuracy and coverage of each source. Previous integration approaches calculate reliabilities of protein interaction information sources based on congruity to a designated ‘gold standard.’ In this paper, we provide a comparison of the two most popular existing approaches and propose a novel alternative for assessing reliabilities which does not require a gold standard. We identify a new method for combining the resultant reliabilities and compare it against an existing method. Further, we propose an extrinsic approach to evaluation of reliability estimates, considering their influence on the downstream tasks of inferring protein function and learning regulatory networks from expression data. Results using this evaluation method show 1) our method for reliability estimation is an attractive alternative to those requiring a gold standard and 2) the new method for combining reliabilities is less sensitive to noise in reliability assignments than the similar existing technique. PMID:17990508
ERIC Educational Resources Information Center
Lerdpornkulrat, Thanita; Poondej, Chanut; Koul, Ravinder
2017-01-01
This study aimed to translate the information-seeking behavior scale from English to Thai, and to ascertain the construct reliability and validity of the scale. Data were collected from 664 undergraduate students in Thailand. The descriptive statistics were explored to see the extent to which various information sources are being used by…
Demographic analysis from summaries of an age-structured population
Link, William A.; Royle, J. Andrew; Hatfield, Jeff S.
2003-01-01
Demographic analyses of age-structured populations typically rely on life history data for individuals, or when individual animals are not identified, on information about the numbers of individuals in each age class through time. While it is usually difficult to determine the age class of a randomly encountered individual, it is often the case that the individual can be readily and reliably assigned to one of a set of age classes. For example, it is often possible to distinguish first-year from older birds. In such cases, the population age structure can be regarded as a latent variable governed by a process prior, and the data as summaries of this latent structure. In this article, we consider the problem of uncovering the latent structure and estimating process parameters from summaries of age class information. We present a demographic analysis for the critically endangered migratory population of whooping cranes (Grus americana), based only on counts of first-year birds and of older birds. We estimate age and year-specific survival rates. We address the controversial issue of whether management action on the breeding grounds has influenced recruitment, relating recruitment rates to the number of seventh-year and older birds, and examining the pattern of variation through time in this rate.
Reliability-based structural optimization: A proposed analytical-experimental study
NASA Technical Reports Server (NTRS)
Stroud, W. Jefferson; Nikolaidis, Efstratios
1993-01-01
An analytical and experimental study for assessing the potential of reliability-based structural optimization is proposed and described. In the study, competing designs obtained by deterministic and reliability-based optimization are compared. The experimental portion of the study is practical because the structure selected is a modular, actively and passively controlled truss that consists of many identical members, and because the competing designs are compared in terms of their dynamic performance and are not destroyed if failure occurs. The analytical portion of this study is illustrated on a 10-bar truss example. In the illustrative example, it is shown that reliability-based optimization can yield a design that is superior to an alternative design obtained by deterministic optimization. These analytical results provide motivation for the proposed study, which is underway.
Venko, Katja; Roy Choudhury, A; Novič, Marjana
2017-01-01
The structural and functional details of transmembrane proteins are vastly underexplored, mostly due to experimental difficulties regarding their solubility and stability. Currently, the majority of transmembrane protein structures are still unknown and this present a huge experimental and computational challenge. Nowadays, thanks to X-ray crystallography or NMR spectroscopy over 3000 structures of membrane proteins have been solved, among them only a few hundred unique ones. Due to the vast biological and pharmaceutical interest in the elucidation of the structure and the functional mechanisms of transmembrane proteins, several computational methods have been developed to overcome the experimental gap. If combined with experimental data the computational information enables rapid, low cost and successful predictions of the molecular structure of unsolved proteins. The reliability of the predictions depends on the availability and accuracy of experimental data associated with structural information. In this review, the following methods are proposed for in silico structure elucidation: sequence-dependent predictions of transmembrane regions, predictions of transmembrane helix-helix interactions, helix arrangements in membrane models, and testing their stability with molecular dynamics simulations. We also demonstrate the usage of the computational methods listed above by proposing a model for the molecular structure of the transmembrane protein bilitranslocase. Bilitranslocase is bilirubin membrane transporter, which shares similar tissue distribution and functional properties with some of the members of the Organic Anion Transporter family and is the only member classified in the Bilirubin Transporter Family. Regarding its unique properties, bilitranslocase is a potentially interesting drug target.
Effects of imperfect automation on decision making in a simulated command and control task.
Rovira, Ericka; McGarry, Kathleen; Parasuraman, Raja
2007-02-01
Effects of four types of automation support and two levels of automation reliability were examined. The objective was to examine the differential impact of information and decision automation and to investigate the costs of automation unreliability. Research has shown that imperfect automation can lead to differential effects of stages and levels of automation on human performance. Eighteen participants performed a "sensor to shooter" targeting simulation of command and control. Dependent variables included accuracy and response time of target engagement decisions, secondary task performance, and subjective ratings of mental work-load, trust, and self-confidence. Compared with manual performance, reliable automation significantly reduced decision times. Unreliable automation led to greater cost in decision-making accuracy under the higher automation reliability condition for three different forms of decision automation relative to information automation. At low automation reliability, however, there was a cost in performance for both information and decision automation. The results are consistent with a model of human-automation interaction that requires evaluation of the different stages of information processing to which automation support can be applied. If fully reliable decision automation cannot be guaranteed, designers should provide users with information automation support or other tools that allow for inspection and analysis of raw data.
Validation of a multidimensional evaluation scale for use in elderly cancer patients.
Monfardini, S; Ferrucci, L; Fratino, L; del Lungo, I; Serraino, D; Zagonel, V
1996-01-15
Although aging is one of the most important risk factors for cancer, elderly patients tend to be excluded from cancer clinical trials, only on the basis of chronologic age. Performance Status (PS) has been used widely to select adult patients for entry into clinical trials, but it does not include a comprehensive evaluation of various age-related factors in the elderly. This study was designed to assess the reliability and validity of a multidimensional geriatric assessment protocol for elderly patients with cancer. Thirty consecutive elderly patients (> or = 65 years), diagnosed with hematologic neoplasia or solid tumors and undergoing chemotherapy or radiotherapy, were given a specifically structured multidimensional questionnaire (MACE) three times during one week by two different physicians. MACE was intended to collect information on demographics, socioeconomic status, cognitive status, depression, physical performance, disability, and tumor characteristics. In parallel with MACE, information was collected by means of the Sickness Impact Profile (SIP). Both for inter-rater and test-retest reliability, the values of the intraclass correlation coefficient (ICC) were generally higher than 0.7. Disability, cognitive status, depressive symptoms, and the number of days spent in bed sick in the last two weeks were markedly correlated with the global, physical, and social SIP score. Disability alone explained 70% of the variance in the SIP global score, 83% of the variance in the SIP physical score, and 45% of the variance in the SIP psychosocial score. MACE proved to be applicable in a reasonable amount of time (around 30 minutes) for a medical oncology ward. These data indicate that this structured evaluation of functional status is feasible and reliable. MACE is therefore proposed as a clinical research tool to avoid arbitrary decisions on patient selection for enrollment in clinical trials, to favor uniform monitoring of treatment, and to allow a better comparison of results.
Costa, Y M; Morita-Neto, O; de Araújo-Júnior, E N S; Sampaio, F A; Conti, P C R; Bonjardim, L R
2017-03-01
Assessing the reliability of medical measurements is a crucial step towards the elaboration of an applicable clinical instrument. There are few studies that evaluate the reliability of somatosensory assessment and pain modulation of masticatory structures. This study estimated the test-retest reliability, that is over time, of the mechanical somatosensory assessment of anterior temporalis, masseter and temporomandibular joint (TMJ) and the conditioned pain modulation (CPM) using the anterior temporalis as the test site. Twenty healthy women were evaluated in two sessions (1 week apart) by the same examiner. Mechanical detection threshold (MDT), mechanical pain threshold (MPT), wind-up ratio (WUR) and pressure pain threshold (PPT) were assessed on the skin overlying the anterior temporalis, masseter and TMJ of the dominant side. CPM was tested by comparing PPT before and during the hand immersion in a hot water bath. anova and intra-class correlation coefficients (ICCs) were applied to the data (α = 5%). The overall ICCs showed acceptable values for the test-retest reliability of mechanical somatosensory assessment of masticatory structures. The ICC values of 75% of all quantitative sensory measurements were considered fair to excellent (fair = 8·4%, good = 33·3% and excellent = 33·3%). However, the CPM paradigm presented poor reliability (ICC = 0·25). The mechanical somatosensory assessment of the masticatory structures, but not the proposed CPM protocol, can be considered sufficiently reliable over time to evaluate the trigeminal sensory function. © 2016 John Wiley & Sons Ltd.
Reliability in the DSM-III field trials: interview v case summary.
Hyler, S E; Williams, J B; Spitzer, R L
1982-11-01
A study compared the reliability of psychiatric diagnoses obtained from the live interviews and from case summaries, on the same patients, by the same clinicians, using the same DSM-III diagnostic criteria. The results showed that the reliability of the major diagnostic classes of DSM-III was higher when diagnoses were made from live interviews than when they were made from case summaries. We conclude that diagnoses based on information contained in traditionally prepared case summaries may lead to an underestimation of the reliability of diagnoses made based on information collected during a "live" interview.
Modeling reliability measurement of interface on information system: Towards the forensic of rules
NASA Astrophysics Data System (ADS)
Nasution, M. K. M.; Sitompul, Darwin; Harahap, Marwan
2018-02-01
Today almost all machines depend on the software. As a software and hardware system depends also on the rules that are the procedures for its use. If the procedure or program can be reliably characterized by involving the concept of graph, logic, and probability, then regulatory strength can also be measured accordingly. Therefore, this paper initiates an enumeration model to measure the reliability of interfaces based on the case of information systems supported by the rules of use by the relevant agencies. An enumeration model is obtained based on software reliability calculation.
NASA Astrophysics Data System (ADS)
Gilmanshin, I. R.; Kirpichnikov, A. P.
2017-09-01
In the result of study of the algorithm of the functioning of the early detection module of excessive losses, it is proven the ability to model it by using absorbing Markov chains. The particular interest is in the study of probability characteristics of early detection module functioning algorithm of losses in order to identify the relationship of indicators of reliability of individual elements, or the probability of occurrence of certain events and the likelihood of transmission of reliable information. The identified relations during the analysis allow to set thresholds reliability characteristics of the system components.
Surrogate data--a secure way to share corporate data.
Tetko, Igor V; Abagyan, Ruben; Oprea, Tudor I
2005-01-01
The privacy of chemical structure is of paramount importance for the industrial sector, in particular for the pharmaceutical industry. At the same time, companies handle large amounts of physico-chemical and biological data that could be shared in order to improve our molecular understanding of pharmacokinetic and toxicological properties, which could lead to improved predictivity and shorten the development time for drugs, in particular in the early phases of drug discovery. The current study provides some theoretical limits on the information required to produce reverse engineering of molecules from generated descriptors and demonstrates that the information content of molecules can be as low as less than one bit per atom. Thus theoretically just one descriptor can be used to completely disclose the molecular structure. Instead of sharing descriptors, we propose to share surrogate data. The sharing of surrogate data is nothing else but sharing of reliably predicted molecules. The use of surrogate data can provide the same information as the original set. We consider the practical application of this idea to predict lipophilicity of chemical compounds and we demonstrate that surrogate and real (original) data provides similar prediction ability. Thus, our proposed strategy makes it possible not only to share descriptors, but also complete collections of surrogate molecules without the danger of disclosing the underlying molecular structures.
Kim, Kwang-Yon; Shin, Seong Eun; No, Kyoung Tai
2015-01-01
Objectives For successful adoption of legislation controlling registration and assessment of chemical substances, it is important to obtain sufficient toxicological experimental evidence and other related information. It is also essential to obtain a sufficient number of predicted risk and toxicity results. Particularly, methods used in predicting toxicities of chemical substances during acquisition of required data, ultimately become an economic method for future dealings with new substances. Although the need for such methods is gradually increasing, the-required information about reliability and applicability range has not been systematically provided. Methods There are various representative environmental and human toxicity models based on quantitative structure-activity relationships (QSAR). Here, we secured the 10 representative QSAR-based prediction models and its information that can make predictions about substances that are expected to be regulated. We used models that predict and confirm usability of the information expected to be collected and submitted according to the legislation. After collecting and evaluating each predictive model and relevant data, we prepared methods quantifying the scientific validity and reliability, which are essential conditions for using predictive models. Results We calculated predicted values for the models. Furthermore, we deduced and compared adequacies of the models using the Alternative non-testing method assessed for Registration, Evaluation, Authorization, and Restriction of Chemicals Substances scoring system, and deduced the applicability domains for each model. Additionally, we calculated and compared inclusion rates of substances expected to be regulated, to confirm the applicability. Conclusions We evaluated and compared the data, adequacy, and applicability of our selected QSAR-based toxicity prediction models, and included them in a database. Based on this data, we aimed to construct a system that can be used with predicted toxicity results. Furthermore, by presenting the suitability of individual predicted results, we aimed to provide a foundation that could be used in actual assessments and regulations. PMID:26206368
Deb, Shoumitro; Bryant, Eleanor; Morris, Paul G; Prior, Lindsay; Lewis, Glyn; Haque, Sayeed
2007-06-01
Develop and assess the psychometric properties of the Carer - Head Injury Participation Scale (C-HIPS) and its biggest factor the Carer - Head Injury Neurobehavioral Assessment Scale (C-HINAS). Furthermore, the aim was to examine the inter-informant reliability by comparing the self reports of individuals with traumatic brain injury (TBI) with the carer reports on the C-HIPS and the C-HINAS. Thirty-two TBI individuals and 27 carers took part in in-depth qualitative interviews exploring the consequences of the TBI. Interview transcripts were analysed and key themes and concepts were used to construct a 49-item and 58-item patient (Patient - Head Injury Participation Scale [P-HIPS]) and carer outcome measure (C-HIPS) respectively, of which 49 were parallel items and nine additional items were used to assess carer burden. Postal versions of the P-HIPS, C-HIPS, Mayo Portland Adaptability Inventory-3 (MPAI-3), and the Glasgow Outcome Scale-Extended (GOSE) were completed by a cohort of 113 TBI individuals and 80 carers. Data from a sub-group of 66 patient/carer pairs were used to compare inter-informant reliability between the P-HIPS and the C-HIPS, and the P-HINAS and the C-HINAS respectively. All individual 49 items of the C-HIPS and their total score showed good test-retest reliability (0.95) and internal consistency (0.95). Comparisons with the MPAI-3 and GOSE found a good correlation with the MPAI-3 (0.7) and a moderate negative correlation with the GOSE (-0.6). Factor analysis of these items extracted a 4-factor structure which represented the domains 'Emotion/Behavior' (C-HINAS), 'Independence/Community Living', 'Cognition', and 'Physical'. The C-HINAS showed good internal consistency (0.92), test-retest reliability (0.93), and concurrent validity with one MPAI subscale (0.7). Assessment of inter-informant reliability revealed good correspondence between the reports of the patients and the carers for both the C-HIPS (0.83) and the C-HINAS (0.82). Both the C-HINAS and the C-HIPS show strong psychometric properties. The qualitative methodology employed in the construction stage of the questionnaires provided good evidence of face and content validity. Comparisons between the P-HIPS and the C-HIPS, and the P-HINAS and the C-HINAS indicated high levels of agreement suggesting that in situations where the patient is unable to provide self-reports, information provided by the carer could be used.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-05
..., RM13-14-000 and RM13-15-000] Monitoring System Conditions--Transmission Operations Reliability...) 502-6817, [email protected] . Robert T. Stroh (Legal Information), Office of the General... Reliability Standards ``address the important reliability goal of ensuring that the transmission system is...
2017 NREL Photovoltaic Reliability Workshop
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurtz, Sarah
NREL's Photovoltaic (PV) Reliability Workshop (PVRW) 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.
Steenson, Sharalyn; Özcebe, Hilal; Arslan, Umut; Konşuk Ünlü, Hande; Araz, Özgür M; Yardim, Mahmut; Üner, Sarp; Bilir, Nazmi; Huang, Terry T-K
2018-01-01
Childhood obesity rates have been rising rapidly in developing countries. A better understanding of the risk factors and social context is necessary to inform public health interventions and policies. This paper describes the validation of several measurement scales for use in Turkey, which relate to child and parent perceptions of physical activity (PA) and enablers and barriers of physical activity in the home environment. The aim of this study was to assess the validity and reliability of several measurement scales in Turkey using a population sample across three socio-economic strata in the Turkish capital, Ankara. Surveys were conducted in Grade 4 children (mean age = 9.7 years for boys; 9.9 years for girls), and their parents, across 6 randomly selected schools, stratified by SES (n = 641 students, 483 parents). Construct validity of the scales was evaluated through exploratory and confirmatory factor analysis. Internal consistency of scales and test-retest reliability were assessed by Cronbach's alpha and intra-class correlation. The scales as a whole were found to have acceptable-to-good model fit statistics (PA Barriers: RMSEA = 0.076, SRMR = 0.0577, AGFI = 0.901; PA Outcome Expectancies: RMSEA = 0.054, SRMR = 0.0545, AGFI = 0.916, and PA Home Environment: RMSEA = 0.038, SRMR = 0.0233, AGFI = 0.976). The PA Barriers subscales showed good internal consistency and poor to fair test-retest reliability (personal α = 0.79, ICC = 0.29, environmental α = 0.73, ICC = 0.59). The PA Outcome Expectancies subscales showed good internal consistency and test-retest reliability (negative α = 0.77, ICC = 0.56; positive α = 0.74, ICC = 0.49). Only the PA Home Environment subscale on support for PA was validated in the final confirmatory model; it showed moderate internal consistency and test-retest reliability (α = 0.61, ICC = 0.48). This study is the first to validate measures of perceptions of physical activity and the physical activity home environment in Turkey. Our results support the originally hypothesized two-factor structures for Physical Activity Barriers and Physical Activity Outcome Expectancies. However, we found the one-factor rather than two-factor structure for Physical Activity Home Environment had the best model fit. This study provides general support for the use of these scales in Turkey in terms of validity, but test-retest reliability warrants further research.
Structural Reliability and Monte Carlo Simulation.
ERIC Educational Resources Information Center
Laumakis, P. J.; Harlow, G.
2002-01-01
Analyzes a simple boom structure and assesses its reliability using elementary engineering mechanics. Demonstrates the power and utility of Monte-Carlo simulation by showing that such a simulation can be implemented more readily with results that compare favorably to the theoretical calculations. (Author/MM)
Booth, Andrew
2016-05-04
Qualitative systematic reviews or qualitative evidence syntheses (QES) are increasingly recognised as a way to enhance the value of systematic reviews (SRs) of clinical trials. They can explain the mechanisms by which interventions, evaluated within trials, might achieve their effect. They can investigate differences in effects between different population groups. They can identify which outcomes are most important to patients, carers, health professionals and other stakeholders. QES can explore the impact of acceptance, feasibility, meaningfulness and implementation-related factors within a real world setting and thus contribute to the design and further refinement of future interventions. To produce valid, reliable and meaningful QES requires systematic identification of relevant qualitative evidence. Although the methodologies of QES, including methods for information retrieval, are well-documented, little empirical evidence exists to inform their conduct and reporting. This structured methodological overview examines papers on searching for qualitative research identified from the Cochrane Qualitative and Implementation Methods Group Methodology Register and from citation searches of 15 key papers. A single reviewer reviewed 1299 references. Papers reporting methodological guidance, use of innovative methodologies or empirical studies of retrieval methods were categorised under eight topical headings: overviews and methodological guidance, sampling, sources, structured questions, search procedures, search strategies and filters, supplementary strategies and standards. This structured overview presents a contemporaneous view of information retrieval for qualitative research and identifies a future research agenda. This review concludes that poor empirical evidence underpins current information practice in information retrieval of qualitative research. A trend towards improved transparency of search methods and further evaluation of key search procedures offers the prospect of rapid development of search methods.
Optimization of Adaptive Intraply Hybrid Fiber Composites with Reliability Considerations
NASA Technical Reports Server (NTRS)
Shiao, Michael C.; Chamis, Christos C.
1994-01-01
The reliability with bounded distribution parameters (mean, standard deviation) was maximized and the reliability-based cost was minimized for adaptive intra-ply hybrid fiber composites by using a probabilistic method. The probabilistic method accounts for all naturally occurring uncertainties including those in constituent material properties, fabrication variables, structure geometry, and control-related parameters. Probabilistic sensitivity factors were computed and used in the optimization procedures. For actuated change in the angle of attack of an airfoil-like composite shell structure with an adaptive torque plate, the reliability was maximized to 0.9999 probability, with constraints on the mean and standard deviation of the actuation material volume ratio (percentage of actuation composite material in a ply) and the actuation strain coefficient. The reliability-based cost was minimized for an airfoil-like composite shell structure with an adaptive skin and a mean actuation material volume ratio as the design parameter. At a O.9-mean actuation material volume ratio, the minimum cost was obtained.
TMFoldWeb: a web server for predicting transmembrane protein fold class.
Kozma, Dániel; Tusnády, Gábor E
2015-09-17
Here we present TMFoldWeb, the web server implementation of TMFoldRec, a transmembrane protein fold recognition algorithm. TMFoldRec uses statistical potentials and utilizes topology filtering and a gapless threading algorithm. It ranks template structures and selects the most likely candidates and estimates the reliability of the obtained lowest energy model. The statistical potential was developed in a maximum likelihood framework on a representative set of the PDBTM database. According to the benchmark test the performance of TMFoldRec is about 77 % in correctly predicting fold class for a given transmembrane protein sequence. An intuitive web interface has been developed for the recently published TMFoldRec algorithm. The query sequence goes through a pipeline of topology prediction and a systematic sequence to structure alignment (threading). Resulting templates are ordered by energy and reliability values and are colored according to their significance level. Besides the graphical interface, a programmatic access is available as well, via a direct interface for developers or for submitting genome-wide data sets. The TMFoldWeb web server is unique and currently the only web server that is able to predict the fold class of transmembrane proteins while assigning reliability scores for the prediction. This method is prepared for genome-wide analysis with its easy-to-use interface, informative result page and programmatic access. Considering the info-communication evolution in the last few years, the developed web server, as well as the molecule viewer, is responsive and fully compatible with the prevalent tablets and mobile devices.
Current status, uncertainty and future needs in soil organic carbon monitoring.
Jandl, Robert; Rodeghiero, Mirco; Martinez, Cristina; Cotrufo, M Francesca; Bampa, Francesca; van Wesemael, Bas; Harrison, Robert B; Guerrini, Iraê Amaral; Richter, Daniel Deb; Rustad, Lindsey; Lorenz, Klaus; Chabbi, Abad; Miglietta, Franco
2014-01-15
Increasing human demands on soil-derived ecosystem services requires reliable data on global soil resources for sustainable development. The soil organic carbon (SOC) pool is a key indicator of soil quality as it affects essential biological, chemical and physical soil functions such as nutrient cycling, pesticide and water retention, and soil structure maintenance. However, information on the SOC pool, and its temporal and spatial dynamics is unbalanced. Even in well-studied regions with a pronounced interest in environmental issues information on soil carbon (C) is inconsistent. Several activities for the compilation of global soil C data are under way. However, different approaches for soil sampling and chemical analyses make even regional comparisons highly uncertain. Often, the procedures used so far have not allowed the reliable estimation of the total SOC pool, partly because the available knowledge is focused on not clearly defined upper soil horizons and the contribution of subsoil to SOC stocks has been less considered. Even more difficult is quantifying SOC pool changes over time. SOC consists of variable amounts of labile and recalcitrant molecules of plant, and microbial and animal origin that are often operationally defined. A comprehensively active soil expert community needs to agree on protocols of soil surveying and lab procedures towards reliable SOC pool estimates. Already established long-term ecological research sites, where SOC changes are quantified and the underlying mechanisms are investigated, are potentially the backbones for regional, national, and international SOC monitoring programs. © 2013.
Durability reliability analysis for corroding concrete structures under uncertainty
NASA Astrophysics Data System (ADS)
Zhang, Hao
2018-02-01
This paper presents a durability reliability analysis of reinforced concrete structures subject to the action of marine chloride. The focus is to provide insight into the role of epistemic uncertainties on durability reliability. The corrosion model involves a number of variables whose probabilistic characteristics cannot be fully determined due to the limited availability of supporting data. All sources of uncertainty, both aleatory and epistemic, should be included in the reliability analysis. Two methods are available to formulate the epistemic uncertainty: the imprecise probability-based method and the purely probabilistic method in which the epistemic uncertainties are modeled as random variables. The paper illustrates how the epistemic uncertainties are modeled and propagated in the two methods, and shows how epistemic uncertainties govern the durability reliability.
Bottema-Beutel, Kristen; Lloyd, Blair; Carter, Erik W; Asmus, Jennifer M
2014-11-01
Attaining reliable estimates of observational measures can be challenging in school and classroom settings, as behavior can be influenced by multiple contextual factors. Generalizability (G) studies can enable researchers to estimate the reliability of observational data, and decision (D) studies can inform how many observation sessions are necessary to achieve a criterion level of reliability. We conducted G and D studies using observational data from a randomized control trial focusing on social and academic participation of students with severe disabilities in inclusive secondary classrooms. Results highlight the importance of anchoring observational decisions to reliability estimates from existing or pilot data sets. We outline steps for conducting G and D studies and address options when reliability estimates are lower than desired.
NASA Astrophysics Data System (ADS)
Banerjee, Sourav; Liu, Lie; Liu, S. T.; Yuan, Fuh-Gwo; Beard, Shawn
2011-04-01
Materials State Awareness (MSA) goes beyond traditional NDE and SHM in its challenge to characterize the current state of material damage before the onset of macro-damage such as cracks. A highly reliable, minimally invasive system for MSA of Aerospace Structures, Naval structures as well as next generation space systems is critically needed. Development of such a system will require a reliable SHM system that can detect the onset of damage well before the flaw grows to a critical size. Therefore, it is important to develop an integrated SHM system that not only detects macroscale damages in the structures but also provides an early indication of flaw precursors and microdamages. The early warning for flaw precursors and their evolution provided by an SHM system can then be used to define remedial strategies before the structural damage leads to failure, and significantly improve the safety and reliability of the structures. Thus, in this article a preliminary concept of developing the Hybrid Distributed Sensor Network Integrated with Self-learning Symbiotic Diagnostic Algorithms and Models to accurately and reliably detect the precursors to damages that occur to the structure are discussed. Experiments conducted in a laboratory environment shows potential of the proposed technique.
NASA Astrophysics Data System (ADS)
Song, Lu-Kai; Wen, Jie; Fei, Cheng-Wei; Bai, Guang-Chen
2018-05-01
To improve the computing efficiency and precision of probabilistic design for multi-failure structure, a distributed collaborative probabilistic design method-based fuzzy neural network of regression (FR) (called as DCFRM) is proposed with the integration of distributed collaborative response surface method and fuzzy neural network regression model. The mathematical model of DCFRM is established and the probabilistic design idea with DCFRM is introduced. The probabilistic analysis of turbine blisk involving multi-failure modes (deformation failure, stress failure and strain failure) was investigated by considering fluid-structure interaction with the proposed method. The distribution characteristics, reliability degree, and sensitivity degree of each failure mode and overall failure mode on turbine blisk are obtained, which provides a useful reference for improving the performance and reliability of aeroengine. Through the comparison of methods shows that the DCFRM reshapes the probability of probabilistic analysis for multi-failure structure and improves the computing efficiency while keeping acceptable computational precision. Moreover, the proposed method offers a useful insight for reliability-based design optimization of multi-failure structure and thereby also enriches the theory and method of mechanical reliability design.
NASA Technical Reports Server (NTRS)
1991-01-01
The technical effort and computer code enhancements performed during the sixth year of the Probabilistic Structural Analysis Methods program are summarized. Various capabilities are described to probabilistically combine structural response and structural resistance to compute component reliability. A library of structural resistance models is implemented in the Numerical Evaluations of Stochastic Structures Under Stress (NESSUS) code that included fatigue, fracture, creep, multi-factor interaction, and other important effects. In addition, a user interface was developed for user-defined resistance models. An accurate and efficient reliability method was developed and was successfully implemented in the NESSUS code to compute component reliability based on user-selected response and resistance models. A risk module was developed to compute component risk with respect to cost, performance, or user-defined criteria. The new component risk assessment capabilities were validated and demonstrated using several examples. Various supporting methodologies were also developed in support of component risk assessment.
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…
Photovoltaic Module Reliability Workshop 2011: February 16-17, 2011
DOE Office of Scientific and Technical Information (OSTI.GOV)
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.
Photovoltaic Module Reliability Workshop 2014: February 25-26, 2014
DOE Office of Scientific and Technical Information (OSTI.GOV)
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.
Photovoltaic Module Reliability Workshop 2013: February 26-27, 2013
DOE Office of Scientific and Technical Information (OSTI.GOV)
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.
Photovoltaic Module Reliability Workshop 2010: February 18-19, 2010
DOE Office of Scientific and Technical Information (OSTI.GOV)
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.
76 FR 28014 - Commission Information Collection Activities (FERC-600); Comment Request; Extension
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-13
... complaint, may order the Electric Reliability Organization to submit to the Commission a proposed reliability standard or a modification to a reliability standard that addresses a specific matter if the Commission considers such a new or modified reliability standard appropriate to carry out this section...
2016 NREL Photovoltaic Module Reliability Workshop
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurtz, Sarah
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.
2015 NREL Photovoltaic Module Reliability Workshops
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurtz, Sarah
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.
Measuring the Process and Quality of Informed Consent for Clinical Research: Development and Testing
Cohn, Elizabeth Gross; Jia, Haomiao; Smith, Winifred Chapman; Erwin, Katherine; Larson, Elaine L.
2013-01-01
Purpose/Objectives To develop and assess the reliability and validity of an observational instrument, the Process and Quality of Informed Consent (P-QIC). Design A pilot study of the psychometrics of a tool designed to measure the quality and process of the informed consent encounter in clinical research. The study used professionally filmed, simulated consent encounters designed to vary in process and quality. Setting A major urban teaching hospital in the northeastern region of the United States. Sample 63 students enrolled in health-related programs participated in psychometric testing, 16 students participated in test-retest reliability, and 5 investigator-participant dyads were observed for the actual consent encounters. Methods For reliability and validity testing, students watched and rated videotaped simulations of four consent encounters intentionally varied in process and content and rated them with the proposed instrument. Test-retest reliability was established by raters watching the videotaped simulations twice. Inter-rater reliability was demonstrated by two simultaneous but independent raters observing an actual consent encounter. Main Research Variables The essential elements of information and communication for informed consent. Findings The initial testing of the P-QIC demonstrated reliable and valid psychometric properties in both the simulated standardized consent encounters and actual consent encounters in the hospital setting. Conclusions The P-QIC is an easy-to-use observational tool that provides a quick assessment of the areas of strength and areas that need improvement in a consent encounter. It can be used in the initial trainings of new investigators or consent administrators and in ongoing programs of improvement for informed consent. Implications for Nursing The development of a validated observational instrument will allow investigators to assess the consent process more accurately and evaluate strategies designed to improve it. PMID:21708532
Reliability measures in item response theory: manifest versus latent correlation functions.
Milanzi, Elasma; Molenberghs, Geert; Alonso, Ariel; Verbeke, Geert; De Boeck, Paul
2015-02-01
For item response theory (IRT) models, which belong to the class of generalized linear or non-linear mixed models, reliability at the scale of observed scores (i.e., manifest correlation) is more difficult to calculate than latent correlation based reliability, but usually of greater scientific interest. This is not least because it cannot be calculated explicitly when the logit link is used in conjunction with normal random effects. As such, approximations such as Fisher's information coefficient, Cronbach's α, or the latent correlation are calculated, allegedly because it is easy to do so. Cronbach's α has well-known and serious drawbacks, Fisher's information is not meaningful under certain circumstances, and there is an important but often overlooked difference between latent and manifest correlations. Here, manifest correlation refers to correlation between observed scores, while latent correlation refers to correlation between scores at the latent (e.g., logit or probit) scale. Thus, using one in place of the other can lead to erroneous conclusions. Taylor series based reliability measures, which are based on manifest correlation functions, are derived and a careful comparison of reliability measures based on latent correlations, Fisher's information, and exact reliability is carried out. The latent correlations are virtually always considerably higher than their manifest counterparts, Fisher's information measure shows no coherent behaviour (it is even negative in some cases), while the newly introduced Taylor series based approximations reflect the exact reliability very closely. Comparisons among the various types of correlations, for various IRT models, are made using algebraic expressions, Monte Carlo simulations, and data analysis. Given the light computational burden and the performance of Taylor series based reliability measures, their use is recommended. © 2014 The British Psychological Society.
NASA Astrophysics Data System (ADS)
Murrad, Muhamad; Leong, M. Salman
Based on the experiences of the Malaysian Armed Forces (MAF), failure of the main rotor gearbox (MRGB) was one of the major contributing factors to helicopter breakdowns. Even though vibration and oil analysis are the effective techniques for monitoring the health of helicopter components, these two techniques were rarely combined to form an effective assessment tool in MAF. Results of the oil analysis were often used only for oil changing schedule while assessments of MRGB condition were mainly based on overall vibration readings. A study group was formed and given a mandate to improve the maintenance strategy of S61-A4 helicopter fleet in the MAF. The improvement consisted of a structured approach to the reassessment/redefinition suitable maintenance actions that should be taken for the MRGB. Basic and enhanced tools for condition monitoring (CM) are investigated to address the predominant failures of the MRGB. Quantitative accelerated life testing (QALT) was considered in this work with an intent to obtain the required reliability information in a shorter time with tests under normal stress conditions. These tests when performed correctly can provide valuable information about MRGB performance under normal operating conditions which enable maintenance personnel to make decision more quickly, accurately and economically. The time-to-failure and probability of failure information of the MRGB were generated by applying QALT analysis principles. This study is anticipated to make a dramatic change in its approach to CM, bringing significant savings and various benefits to MAF.
McIntosh, Heather M; Calvert, Julie; Macpherson, Karen J; Thompson, Lorna
2016-06-01
Rapid review has become widely adopted by health technology assessment agencies in response to demand for evidence-based information to support imperative decisions. Concern about the credibility of rapid reviews and the reliability of their findings has prompted a call for wider publication of their methods. In publishing this overview of the accredited rapid review process developed by Healthcare Improvement Scotland, we aim to raise awareness of our methods and advance the discourse on best practice. Healthcare Improvement Scotland produces rapid reviews called evidence notes using a process that has achieved external accreditation through the National Institute for Health and Care Excellence. Key components include a structured approach to topic selection, initial scoping, considered stakeholder involvement, streamlined systematic review, internal quality assurance, external peer review and updating. The process was introduced in 2010 and continues to be refined over time in response to user feedback and operational experience. Decision-makers value the responsiveness of the process and perceive it as being a credible source of unbiased evidence-based information supporting advice for NHSScotland. Many agencies undertaking rapid reviews are striving to balance efficiency with methodological rigour. We agree that there is a need for methodological guidance and that it should be informed by better understanding of current approaches and the consequences of different approaches to streamlining systematic review methods. Greater transparency in the reporting of rapid review methods is essential to enable that to happen.
Kilov, Andrea M; Togher, Leanne; Power, Emma
2015-01-01
To determine test-re-test reliability of the 'Computer User Profile' (CUP) in people with and without TBI. The CUP was administered on two occasions to people with and without TBI. The CUP investigated the nature and frequency of participants' computer and Internet use. Intra-class correlation coefficients and kappa coefficients were conducted to measure reliability of individual CUP items. Descriptive statistics were used to summarize content of responses. Sixteen adults with TBI and 40 adults without TBI were included in the study. All participants were reliable in reporting demographic information, frequency of social communication and leisure activities and computer/Internet habits and usage. Adults with TBI were reliable in 77% of their responses to survey items. Adults without TBI were reliable in 88% of their responses to survey items. The CUP was practical and valuable in capturing information about social, leisure, communication and computer/Internet habits of people with and without TBI. Adults without TBI scored more items with satisfactory reliability overall in their surveys. Future studies may include larger samples and could also include an exploration of how people with/without TBI use other digital communication technologies. This may provide further information on determining technology readiness for people with TBI in therapy programmes.
Finger-vein and fingerprint recognition based on a feature-level fusion method
NASA Astrophysics Data System (ADS)
Yang, Jinfeng; Hong, Bofeng
2013-07-01
Multimodal biometrics based on the finger identification is a hot topic in recent years. In this paper, a novel fingerprint-vein based biometric method is proposed to improve the reliability and accuracy of the finger recognition system. First, the second order steerable filters are used here to enhance and extract the minutiae features of the fingerprint (FP) and finger-vein (FV). Second, the texture features of fingerprint and finger-vein are extracted by a bank of Gabor filter. Third, a new triangle-region fusion method is proposed to integrate all the fingerprint and finger-vein features in feature-level. Thus, the fusion features contain both the finger texture-information and the minutiae triangular geometry structure. Finally, experimental results performed on the self-constructed finger-vein and fingerprint databases are shown that the proposed method is reliable and precise in personal identification.
Neuroplasticity and functional recovery in multiple sclerosis
Tomassini, Valentina; Matthews, Paul M.; Thompson, Alan J.; Fuglø, Daniel; Geurts, Jeroen J.; Johansen-Berg, Heidi; Jones, Derek K.; Rocca, Maria A.; Wise, Richard G.; Barkhof, Frederik; Palace, Jacqueline
2013-01-01
The development of therapeutic strategies that promote functional recovery is a major goal of multiple sclerosis (MS) research. Neuroscientific and methodological advances have improved our understanding of the brain’s recovery from damage, generating novel hypotheses for potential targets or modes of intervention and laying the foundation for the development of scientifically informed strategies promoting recovery in interventional studies. This Review aims to encourage the transition from characterization of recovery mechanisms to the development of strategies that promote recovery in MS. We discuss current evidence for functional reorganization that underlies recovery and its implications for development of new recovery-oriented strategies in MS. Promotion of functional recovery requires an improved understanding of recovery mechanisms modulated by interventions and the development of reliable measures of therapeutic effects. As imaging methods can be used to measure functional and structural alterations associated with recovery, this Review discusses their use as reliable markers to measure the effects of interventions. PMID:22986429
Coupling MD Simulations and X-ray Absorption Spectroscopy to Study Ions in Solution
NASA Astrophysics Data System (ADS)
Marcos, E. Sánchez; Beret, E. C.; Martínez, J. M.; Pappalardo, R. R.; Ayala, R.; Muñoz-Páez, A.
2007-12-01
The structure of ionic solutions is a key-point in understanding physicochemical properties of electrolyte solutions. Among the reduced number of experimental techniques which can supply direct information on the ion environment, X-ray Absorption techniques (XAS) have gained importance during the last decades although they are not free of difficulties associated to the data analysis leading to provide reliable structures. Computer simulations of ions in solution is a theoretical alternative to provide information on the solvation structure. Thus, the use of computational chemistry can increase the understanding of these systems although an accurate description of ionic solvation phenomena represents nowadays a significant challenge to theoretical chemistry. We present: (a) the assignment of features in the XANES spectrum to well defined structural motif in the ion environment, (b) MD-based evaluation of EXAFS parameters used in the fitting procedure to make easier the structural resolution, and (c) the use of the agreement between experimental and simulated XANES spectra to help in the choice of a given intermolecular potential for Computer Simulations. Chemical problems examined are: (a) the identification of the second hydration shell in dilute aqueous solutions of highly-charged cations, such as Cr3+, Rh3+, Ir3+, (b) the invisibility by XAS of certain structures characterized by Computer Simulations but exhibiting high dynamical behavior and (c) the solvation of Br- in acetonitrile.
Coupling MD Simulations and X-ray Absorption Spectroscopy to Study Ions in Solution
NASA Astrophysics Data System (ADS)
Marcos, E. Sánchez; Beret, E. C.; Martínez, J. M.; Pappalardo, R. R.; Ayala, R.; Muñoz-Páez, A.
2007-11-01
The structure of ionic solutions is a key-point in understanding physicochemical properties of electrolyte solutions. Among the reduced number of experimental techniques which can supply direct information on the ion environment, X-ray Absorption techniques (XAS) have gained importance during the last decades although they are not free of difficulties associated to the data analysis leading to provide reliable structures. Computer simulations of ions in solution is a theoretical alternative to provide information on the solvation structure. Thus, the use of computational chemistry can increase the understanding of these systems although an accurate description of ionic solvation phenomena represents nowadays a significant challenge to theoretical chemistry. We present: (a) the assignment of features in the XANES spectrum to well defined structural motif in the ion environment, (b) MD-based evaluation of EXAFS parameters used in the fitting procedure to make easier the structural resolution, and (c) the use of the agreement between experimental and simulated XANES spectra to help in the choice of a given intermolecular potential for Computer Simulations. Chemical problems examined are: (a) the identification of the second hydration shell in dilute aqueous solutions of highly-charged cations, such as Cr3+, Rh3+, Ir3+, (b) the invisibility by XAS of certain structures characterized by Computer Simulations but exhibiting high dynamical behavior and (c) the solvation of Br- in acetonitrile.
The transition of ground-based space environmental effects testing to the space environment
NASA Technical Reports Server (NTRS)
Zaat, Stephen V.; Schaefer, Glen A.; Wallace, John F.
1991-01-01
The goal of the space flight program at the Center for Commercial Development of Space (CCDS)--Materials for Space Structures is to provide environmentally stable structural materials to support the continued humanization and commercialization of the space frontier. Information on environmental stability will be obtained through space exposure, evaluation, documentation, and subsequent return to the supplier of the candidate material for internal investigation. This program provides engineering and scientific service to space systems development firms and also exposes CCDS development candidate materials to space environments representative of in-flight conditions. The maintenance of a technological edge in space for NASA suggests the immediate search for space materials that maintain their structural integrity and remain environmentally stable. The materials being considered for long-lived space structures are complex, high strength/weight ratio composites. In order for these new candidate materials to qualify for use in space structures, they must undergo strenuous testing to determine their reliability and stability when subjected to the space environment. Ultraviolet radiation, atomic oxygen, debris/micrometeoroids, charged particles radiation, and thermal fatigue all influence the design of space structural materials. The investigation of these environmental interactions is the key purpose of this center. Some of the topics discussed with respect to the above information include: the Space Transportation System, mission planning, spaceborne experiments, and space flight payloads.
Quality of online information to support patient decision-making in breast cancer surgery.
Bruce, Jordan G; Tucholka, Jennifer L; Steffens, Nicole M; Neuman, Heather B
2015-11-01
Breast cancer patients commonly use the internet as an information resource. Our objective was to evaluate the quality of online information available to support patients facing a decision for breast surgery. Breast cancer surgery-related queries were performed (Google and Bing), and reviewed for content pertinent to breast cancer surgery. The DISCERN instrument was used to evaluate websites' structural components that influence publication reliability and ability of information to support treatment decision-making. Scores of 4/5 were considered "good." 45 unique websites were identified. Websites satisfied a median 5/9 content questions. Commonly omitted topics included: having a choice between breast conservation and mastectomy (67%) and potential for 2nd surgery to obtain negative margins after breast conservation (60%). Websites had a median DISCERN score of 2.9 (range 2.0-4.5). Websites achieved higher scores on structural criteria (median 3.6 [2.1-4.7]), with 24% rated as "good." Scores on supporting decision-making questions were lower (2.6 [1.3-4.4]), with only 7% scoring "good." Although numerous breast cancer-related websites exist, most do a poor job providing women with essential information necessary to actively participate in decision-making for breast cancer surgery. Providing easily- accessible, high-quality online information has the potential to significantly improve patients' experiences with decision-making. © 2015 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Nagy, Julia; Eilert, Tobias; Michaelis, Jens
2018-03-01
Modern hybrid structural analysis methods have opened new possibilities to analyze and resolve flexible protein complexes where conventional crystallographic methods have reached their limits. Here, the Fast-Nano-Positioning System (Fast-NPS), a Bayesian parameter estimation-based analysis method and software, is an interesting method since it allows for the localization of unknown fluorescent dye molecules attached to macromolecular complexes based on single-molecule Förster resonance energy transfer (smFRET) measurements. However, the precision, accuracy, and reliability of structural models derived from results based on such complex calculation schemes are oftentimes difficult to evaluate. Therefore, we present two proof-of-principle benchmark studies where we use smFRET data to localize supposedly unknown positions on a DNA as well as on a protein-nucleic acid complex. Since we use complexes where structural information is available, we can compare Fast-NPS localization to the existing structural data. In particular, we compare different dye models and discuss how both accuracy and precision can be optimized.
A general strategy to solve the phase problem in RNA crystallography
Keel, Amanda Y.; Rambo, Robert P.; Batey, Robert T.; Kieft, Jeffrey S.
2007-01-01
SUMMARY X-ray crystallography of biologically important RNA molecules has been hampered by technical challenges, including finding a heavy-atom derivative to obtain high-quality experimental phase information. Existing techniques have drawbacks, severely limiting the rate at which important new structures are solved. To address this need, we have developed a reliable means to localize heavy atoms specifically to virtually any RNA. By solving the crystal structures of thirteen variants of the G·U wobble pair cation binding motif we have identified an optimal version that when inserted into an RNA helix introduces a high-occupancy cation binding site suitable for phasing. This “directed soaking” strategy can be integrated fully into existing RNA and crystallography methods, potentially increasing the rate at which important structures are solved and facilitating routine solving of structures using Cu-Kα radiation. The success of this method has been proven in that it has already been used to solve several novel crystal structures. PMID:17637337
DOT National Transportation Integrated Search
2003-12-01
This study explores the on-time reliability benefits to potential users of a personalized advanced traveler information system (ATIS) providing real-time pre-trip roadway information for the Seattle morning peak period through the application of Heur...
DOT National Transportation Integrated Search
2013-11-30
Travel time reliability information includes static data about traffic speeds or trip times that capture historic variations from day to day, and it can help individuals understand the level of variation in traffic. Unlike real-time travel time infor...
75 FR 5779 - Proposed Emergency Agency Information Collection
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-04
... proposed collection of information, including the validity of the methodology and assumptions used; (c... Collection Request Title: Electricity Delivery and Energy Reliability Recovery Act Smart Grid Grant Program..., Chief Operating Officer, Electricity Delivery and Energy Reliability. [FR Doc. 2010-2422 Filed 2-3-10; 8...
Weighted integration of short-term memory and sensory signals in the oculomotor system.
Deravet, Nicolas; Blohm, Gunnar; de Xivry, Jean-Jacques Orban; Lefèvre, Philippe
2018-05-01
Oculomotor behaviors integrate sensory and prior information to overcome sensory-motor delays and noise. After much debate about this process, reliability-based integration has recently been proposed and several models of smooth pursuit now include recurrent Bayesian integration or Kalman filtering. However, there is a lack of behavioral evidence in humans supporting these theoretical predictions. Here, we independently manipulated the reliability of visual and prior information in a smooth pursuit task. Our results show that both smooth pursuit eye velocity and catch-up saccade amplitude were modulated by visual and prior information reliability. We interpret these findings as the continuous reliability-based integration of a short-term memory of target motion with visual information, which support modeling work. Furthermore, we suggest that saccadic and pursuit systems share this short-term memory. We propose that this short-term memory of target motion is quickly built and continuously updated, and constitutes a general building block present in all sensorimotor systems.
Meylan, Grégoire; Reck, Barbara K; Rechberger, Helmut; Graedel, Thomas E; Schwab, Oliver
2017-10-17
Decision-makers traditionally expect "hard facts" from scientific inquiry, an expectation that the results of material flow analyses (MFAs) can hardly meet. MFA limitations are attributable to incompleteness of flowcharts, limited data quality, and model assumptions. Moreover, MFA results are, for the most part, based less on empirical observation but rather on social knowledge construction processes. Developing, applying, and improving the means of evaluating and communicating the reliability of MFA results is imperative. We apply two recently proposed approaches for making quantitative statements on MFA reliability to national minor metals systems: rhenium, gallium, and germanium in the United States in 2012. We discuss the reliability of results in policy and management contexts. The first approach consists of assessing data quality based on systematic characterization of MFA data and the associated meta-information and quantifying the "information content" of MFAs. The second is a quantification of data inconsistencies indicated by the "degree of data reconciliation" between the data and the model. A high information content and a low degree of reconciliation indicate reliable or certain MFA results. This article contributes to reliability and uncertainty discourses in MFA, exemplifying the usefulness of the approaches in policy and management, and to raw material supply discussions by providing country-level information on three important minor metals often considered critical.
Reliability-based optimization of an active vibration controller using evolutionary algorithms
NASA Astrophysics Data System (ADS)
Saraygord Afshari, Sajad; Pourtakdoust, Seid H.
2017-04-01
Many modern industrialized systems such as aircrafts, rotating turbines, satellite booms, etc. cannot perform their desired tasks accurately if their uninhibited structural vibrations are not controlled properly. Structural health monitoring and online reliability calculations are emerging new means to handle system imposed uncertainties. As stochastic forcing are unavoidable, in most engineering systems, it is often needed to take them into the account for the control design process. In this research, smart material technology is utilized for structural health monitoring and control in order to keep the system in a reliable performance range. In this regard, a reliability-based cost function is assigned for both controller gain optimization as well as sensor placement. The proposed scheme is implemented and verified for a wing section. Comparison of results for the frequency responses is considered to show potential applicability of the presented technique.
A Numerical Round Robin for the Reliability Prediction of Structural Ceramics
NASA Technical Reports Server (NTRS)
Powers, Lynn M.; Janosik, Lesley A.
1993-01-01
A round robin has been conducted on integrated fast fracture design programs for brittle materials. An informal working group (WELFEP-WEakest Link failure probability prediction by Finite Element Postprocessors) was formed to discuss and evaluate the implementation of the programs examined in the study. Results from the study have provided insight on the differences between the various programs examined. Conclusions from the study have shown that when brittle materials are used in design, analysis must understand how to apply the concepts presented herein to failure probability analysis.
Terminal-oriented computer-communication networks.
NASA Technical Reports Server (NTRS)
Schwartz, M.; Boorstyn, R. R.; Pickholtz, R. L.
1972-01-01
Four examples of currently operating computer-communication networks are described in this tutorial paper. They include the TYMNET network, the GE Information Services network, the NASDAQ over-the-counter stock-quotation system, and the Computer Sciences Infonet. These networks all use programmable concentrators for combining a multiplicity of terminals. Included in the discussion for each network is a description of the overall network structure, the handling and transmission of messages, communication requirements, routing and reliability consideration where applicable, operating data and design specifications where available, and unique design features in the area of computer communications.
NASA Technical Reports Server (NTRS)
1987-01-01
Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.
Structure of turbulence in three-dimensional boundary layers
NASA Technical Reports Server (NTRS)
Subramanian, Chelakara S.
1993-01-01
This report provides an overview of the three dimensional turbulent boundary layer concepts and of the currently available experimental information for their turbulence modeling. It is found that more reliable turbulence data, especially of the Reynolds stress transport terms, is needed to improve the existing modeling capabilities. An experiment is proposed to study the three dimensional boundary layer formed by a 'sink flow' in a fully developed two dimensional turbulent boundary layer. Also, the mean and turbulence field measurement procedure using a three component laser Doppler velocimeter is described.
Active optical control system design of the SONG-China Telescope
NASA Astrophysics Data System (ADS)
Ye, Yu; Kou, Songfeng; Niu, Dongsheng; Li, Cheng; Wang, Guomin
2012-09-01
The standard SONG node structure of control system is presented. The active optical control system of the project is a distributed system, and a host computer and a slave intelligent controller are included. The host control computer collects the information from wave front sensor and sends commands to the slave computer to realize a closed loop model. For intelligent controller, a programmable logic controller (PLC) system is used. This system combines with industrial personal computer (IPC) and PLC to make up a control system with powerful and reliable.
A portable battery for objective, non-obstrusive measures of human performances
NASA Technical Reports Server (NTRS)
Kennedy, R. S.
1984-01-01
The need for a standardized battery of human performance tests to measure the effects of various treatments is pointed out. Progress in such a program is reported. Three batteries are available which differ in length and the number of tests in the battery. All tests are implemented on a portable, lap held, briefcase size microprocessor. Performances measured include: information processing, memory, visual perception, reasoning, and motor skills, programs to determine norms, reliabilities, stabilities, factor structure of tests, comparisons with marker tests, apparatus suitability. Rationale for the battery is provided.
Packaging of structural health monitoring components
NASA Astrophysics Data System (ADS)
Kessler, Seth S.; Spearing, S. Mark; Shi, Yong; Dunn, Christopher T.
2004-07-01
Structural Health Monitoring (SHM) technologies have the potential to realize economic benefits in a broad range of commercial and defense markets. Previous research conducted by Metis Design and MIT has demonstrated the ability of Lamb waves methods to provide reliable information regarding the presence, location and type of damage in composite specimens. The present NSF funded program was aimed to study manufacturing, packaging and interface concepts for critical SHM components. The intention is to be able to cheaply manufacture robust actuating/sensing devices, and isolate them from harsh operating environments including natural, mechanical, or electrical extremes. Currently the issues related to SHM system durability have remained undressed. During the course of this research several sets of test devices were fabricated and packaged to protect the piezoelectric component assemblies for robust operation. These assemblies were then tested in hot and wet conditions, as well as in electrically noisy environments. Future work will aim to package the other supporting components such as the battery and wireless chip, as well as integrating all of these components together for operation. SHM technology will enable the reduction or complete elimination of scheduled inspections, and will allow condition-based maintenance for increased reliability and reduced overall life-cycle costs.
Social Cognition as Reinforcement Learning: Feedback Modulates Emotion Inference.
Zaki, Jamil; Kallman, Seth; Wimmer, G Elliott; Ochsner, Kevin; Shohamy, Daphna
2016-09-01
Neuroscientific studies of social cognition typically employ paradigms in which perceivers draw single-shot inferences about the internal states of strangers. Real-world social inference features much different parameters: People often encounter and learn about particular social targets (e.g., friends) over time and receive feedback about whether their inferences are correct or incorrect. Here, we examined this process and, more broadly, the intersection between social cognition and reinforcement learning. Perceivers were scanned using fMRI while repeatedly encountering three social targets who produced conflicting visual and verbal emotional cues. Perceivers guessed how targets felt and received feedback about whether they had guessed correctly. Visual cues reliably predicted one target's emotion, verbal cues predicted a second target's emotion, and neither reliably predicted the third target's emotion. Perceivers successfully used this information to update their judgments over time. Furthermore, trial-by-trial learning signals-estimated using two reinforcement learning models-tracked activity in ventral striatum and ventromedial pFC, structures associated with reinforcement learning, and regions associated with updating social impressions, including TPJ. These data suggest that learning about others' emotions, like other forms of feedback learning, relies on domain-general reinforcement mechanisms as well as domain-specific social information processing.
Speaker-Sex Discrimination for Voiced and Whispered Vowels at Short Durations
2016-01-01
Whispered vowels, produced with no vocal fold vibration, lack the periodic temporal fine structure which in voiced vowels underlies the perceptual attribute of pitch (a salient auditory cue to speaker sex). Voiced vowels possess no temporal fine structure at very short durations (below two glottal cycles). The prediction was that speaker-sex discrimination performance for whispered and voiced vowels would be similar for very short durations but, as stimulus duration increases, voiced vowel performance would improve relative to whispered vowel performance as pitch information becomes available. This pattern of results was shown for women’s but not for men’s voices. A whispered vowel needs to have a duration three times longer than a voiced vowel before listeners can reliably tell whether it’s spoken by a man or woman (∼30 ms vs. ∼10 ms). Listeners were half as sensitive to information about speaker-sex when it is carried by whispered compared with voiced vowels. PMID:27757218
EarthCARE mission, overview, implementation approach and development status
NASA Astrophysics Data System (ADS)
Lefebvre, Alain; Hélière, Arnaud; Pérez Albiñana, Abelardo; Wallace, Kotska; Maeusli, Damien; Lemanczyk, Jerzy; Lusteau, Cyrille; Nakatsuka, Hirotaka; Tomita, Eiichi
2016-05-01
The European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) are co-operating to develop the EarthCARE satellite mission with the fundamental objective of improving the understanding of the processes involving clouds, aerosols and radiation in the Earth's atmosphere in order to include them correctly and reliably in climate and numerical weather prediction models. The satellite will be placed in a Sun-Synchronous Orbit at about 400 Km altitude and14h00 mean local solar time. The payload consisting of a High Spectral Resolution UV Atmospheric LIDar (ATLID), a 94GHz Cloud Profiling Radar (CPR) with Doppler capability, a Multi-Spectral Imager (MSI) and a Broad-Band Radiometer will provide information on cloud and aerosol vertical structure of the atmosphere along the satellite track as well as information about the horizontal structures of clouds and radiant flux from sub-satellite cells. The presentation will cover the configuration of the satellite with its four instruments, the mission implementation approach, an overview of the ground segment and the overall mission development status.
Mfold web server for nucleic acid folding and hybridization prediction
Zuker, Michael
2003-01-01
The abbreviated name, ‘mfold web server’, describes a number of closely related software applications available on the World Wide Web (WWW) for the prediction of the secondary structure of single stranded nucleic acids. The objective of this web server is to provide easy access to RNA and DNA folding and hybridization software to the scientific community at large. By making use of universally available web GUIs (Graphical User Interfaces), the server circumvents the problem of portability of this software. Detailed output, in the form of structure plots with or without reliability information, single strand frequency plots and ‘energy dot plots’, are available for the folding of single sequences. A variety of ‘bulk’ servers give less information, but in a shorter time and for up to hundreds of sequences at once. The portal for the mfold web server is http://www.bioinfo.rpi.edu/applications/mfold. This URL will be referred to as ‘MFOLDROOT’. PMID:12824337
A new informant-based questionnaire for instrumental activities of daily living in dementia.
Sikkes, Sietske A M; de Lange-de Klerk, Elly S M; Pijnenburg, Yolande A L; Gillissen, Freek; Romkes, Rolinka; Knol, Dirk L; Uitdehaag, Bernard M J; Scheltens, Philip
2012-11-01
Interference in everyday functioning is part of the diagnostic criteria for dementia. Questionnaires measuring "instrumental activities of daily living" (IADL) are used to measure this interference, but the psychometric quality of these questionnaires is often questioned. In addition, these questionnaires are less suited for early-onset patients. This is problematic, given the high frequency of relatively young patients in memory clinics. In this article, we describe the development and psychometric properties of a new informant-based IADL questionnaire aimed at detecting incipient dementia and appropriate for a broad age range. We defined IADL in consensus with experts and constructed items based on existing items and suggestions from experts and informants. Informants of subjects (n = 206) who visited the Alzheimer Center of the VU University Medical Center completed the questionnaire. Factor structure was investigated using classical exploratory factor analysis and item response theory. We assessed test-retest reliability in 73 informants using weighted κ values. The questionnaire consisted of 75 items and was computerized to enhance ease of administration. Exploratory factor analysis supported a single-factor model, with 48.3% of the variance being explained by the first factor. We removed five items, as they did not fit the model. High internal consistency was demonstrated. Test-retest reliability showed that the majority of items (87.9%) had substantial-to-almost perfect κ values. The Amsterdam IADL Questionnaire (Amsterdam IADL questionnaire is a registered trademark of Alzheimer Center VU University Medical Center, Amsterdam, The Netherlands) is a 70-item informant-based computerized questionnaire aimed at detecting early dementia and early-onset dementia. Initial results show that this questionnaire is a promising new tool. Copyright © 2012 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
Study on safety level of RC beam bridges under earthquake
NASA Astrophysics Data System (ADS)
Zhao, Jun; Lin, Junqi; Liu, Jinlong; Li, Jia
2017-08-01
This study considers uncertainties in material strengths and the modeling which have important effects on structural resistance force based on reliability theory. After analyzing the destruction mechanism of a RC bridge, structural functions and the reliability were given, then the safety level of the piers of a reinforced concrete continuous girder bridge with stochastic structural parameters against earthquake was analyzed. Using response surface method to calculate the failure probabilities of bridge piers under high-level earthquake, their seismic reliability for different damage states within the design reference period were calculated applying two-stage design, which describes seismic safety level of the built bridges to some extent.
An advanced probabilistic structural analysis method for implicit performance functions
NASA Technical Reports Server (NTRS)
Wu, Y.-T.; Millwater, H. R.; Cruse, T. A.
1989-01-01
In probabilistic structural analysis, the performance or response functions usually are implicitly defined and must be solved by numerical analysis methods such as finite element methods. In such cases, the most commonly used probabilistic analysis tool is the mean-based, second-moment method which provides only the first two statistical moments. This paper presents a generalized advanced mean value (AMV) method which is capable of establishing the distributions to provide additional information for reliability design. The method requires slightly more computations than the second-moment method but is highly efficient relative to the other alternative methods. In particular, the examples show that the AMV method can be used to solve problems involving non-monotonic functions that result in truncated distributions.